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llvm / llvm-project / 23b6709c72357c8b8f0ffa6cdbd860977441982b / . / llvm / lib / Target / AArch64 / AArch64InstrInfo.cpp
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//===- AArch64InstrInfo.cpp - AArch64 Instruction Information -------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains the AArch64 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "AArch64InstrInfo.h"
#include "AArch64ExpandImm.h"
#include "AArch64FrameLowering.h"
#include "AArch64MachineFunctionInfo.h"
#include "AArch64PointerAuth.h"
#include "AArch64Subtarget.h"
#include "MCTargetDesc/AArch64AddressingModes.h"
#include "Utils/AArch64BaseInfo.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/CodeGen/LivePhysRegs.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineCombinerPattern.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineOperand.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterScavenging.h"
#include "llvm/CodeGen/StackMaps.h"
#include "llvm/CodeGen/TargetRegisterInfo.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/IR/DebugInfoMetadata.h"
#include "llvm/IR/DebugLoc.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstBuilder.h"
#include "llvm/MC/MCInstrDesc.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CodeGen.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/LEB128.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include <cassert>
#include <cstdint>
#include <iterator>
#include <utility>
using namespace llvm;
#define GET_INSTRINFO_CTOR_DTOR
#include "AArch64GenInstrInfo.inc"
static cl::opt<unsigned> TBZDisplacementBits(
"aarch64-tbz-offset-bits", cl::Hidden, cl::init(14),
cl::desc("Restrict range of TB[N]Z instructions (DEBUG)"));
static cl::opt<unsigned> CBZDisplacementBits(
"aarch64-cbz-offset-bits", cl::Hidden, cl::init(19),
cl::desc("Restrict range of CB[N]Z instructions (DEBUG)"));
static cl::opt<unsigned>
BCCDisplacementBits("aarch64-bcc-offset-bits", cl::Hidden, cl::init(19),
cl::desc("Restrict range of Bcc instructions (DEBUG)"));
static cl::opt<unsigned>
BDisplacementBits("aarch64-b-offset-bits", cl::Hidden, cl::init(26),
cl::desc("Restrict range of B instructions (DEBUG)"));
AArch64InstrInfo::AArch64InstrInfo(const AArch64Subtarget &STI)
: AArch64GenInstrInfo(AArch64::ADJCALLSTACKDOWN, AArch64::ADJCALLSTACKUP,
AArch64::CATCHRET),
RI(STI.getTargetTriple()), Subtarget(STI) {}
/// GetInstSize - Return the number of bytes of code the specified
/// instruction may be. This returns the maximum number of bytes.
unsigned AArch64InstrInfo::getInstSizeInBytes(const MachineInstr &MI) const {
const MachineBasicBlock &MBB = *MI.getParent();
const MachineFunction *MF = MBB.getParent();
const Function &F = MF->getFunction();
const MCAsmInfo *MAI = MF->getTarget().getMCAsmInfo();
{
auto Op = MI.getOpcode();
if (Op == AArch64::INLINEASM || Op == AArch64::INLINEASM_BR)
return getInlineAsmLength(MI.getOperand(0).getSymbolName(), *MAI);
}
// Meta-instructions emit no code.
if (MI.isMetaInstruction())
return 0;
// FIXME: We currently only handle pseudoinstructions that don't get expanded
// before the assembly printer.
unsigned NumBytes = 0;
const MCInstrDesc &Desc = MI.getDesc();
// Size should be preferably set in
// llvm/lib/Target/AArch64/AArch64InstrInfo.td (default case).
// Specific cases handle instructions of variable sizes
switch (Desc.getOpcode()) {
default:
if (Desc.getSize())
return Desc.getSize();
// Anything not explicitly designated otherwise (i.e. pseudo-instructions
// with fixed constant size but not specified in .td file) is a normal
// 4-byte insn.
NumBytes = 4;
break;
case TargetOpcode::STACKMAP:
// The upper bound for a stackmap intrinsic is the full length of its shadow
NumBytes = StackMapOpers(&MI).getNumPatchBytes();
assert(NumBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
break;
case TargetOpcode::PATCHPOINT:
// The size of the patchpoint intrinsic is the number of bytes requested
NumBytes = PatchPointOpers(&MI).getNumPatchBytes();
assert(NumBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
break;
case TargetOpcode::STATEPOINT:
NumBytes = StatepointOpers(&MI).getNumPatchBytes();
assert(NumBytes % 4 == 0 && "Invalid number of NOP bytes requested!");
// No patch bytes means a normal call inst is emitted
if (NumBytes == 0)
NumBytes = 4;
break;
case TargetOpcode::PATCHABLE_FUNCTION_ENTER:
// If `patchable-function-entry` is set, PATCHABLE_FUNCTION_ENTER
// instructions are expanded to the specified number of NOPs. Otherwise,
// they are expanded to 36-byte XRay sleds.
NumBytes =
F.getFnAttributeAsParsedInteger("patchable-function-entry", 9) * 4;
break;
case TargetOpcode::PATCHABLE_FUNCTION_EXIT:
case TargetOpcode::PATCHABLE_TYPED_EVENT_CALL:
// An XRay sled can be 4 bytes of alignment plus a 32-byte block.
NumBytes = 36;
break;
case TargetOpcode::PATCHABLE_EVENT_CALL:
// EVENT_CALL XRay sleds are exactly 6 instructions long (no alignment).
NumBytes = 24;
break;
case AArch64::SPACE:
NumBytes = MI.getOperand(1).getImm();
break;
case TargetOpcode::BUNDLE:
NumBytes = getInstBundleLength(MI);
break;
}
return NumBytes;
}
unsigned AArch64InstrInfo::getInstBundleLength(const MachineInstr &MI) const {
unsigned Size = 0;
MachineBasicBlock::const_instr_iterator I = MI.getIterator();
MachineBasicBlock::const_instr_iterator E = MI.getParent()->instr_end();
while (++I != E && I->isInsideBundle()) {
assert(!I->isBundle() && "No nested bundle!");
Size += getInstSizeInBytes(*I);
}
return Size;
}
static void parseCondBranch(MachineInstr *LastInst, MachineBasicBlock *&Target,
SmallVectorImpl<MachineOperand> &Cond) {
// Block ends with fall-through condbranch.
switch (LastInst->getOpcode()) {
default:
llvm_unreachable("Unknown branch instruction?");
case AArch64::Bcc:
Target = LastInst->getOperand(1).getMBB();
Cond.push_back(LastInst->getOperand(0));
break;
case AArch64::CBZW:
case AArch64::CBZX:
case AArch64::CBNZW:
case AArch64::CBNZX:
Target = LastInst->getOperand(1).getMBB();
Cond.push_back(MachineOperand::CreateImm(-1));
Cond.push_back(MachineOperand::CreateImm(LastInst->getOpcode()));
Cond.push_back(LastInst->getOperand(0));
break;
case AArch64::TBZW:
case AArch64::TBZX:
case AArch64::TBNZW:
case AArch64::TBNZX:
Target = LastInst->getOperand(2).getMBB();
Cond.push_back(MachineOperand::CreateImm(-1));
Cond.push_back(MachineOperand::CreateImm(LastInst->getOpcode()));
Cond.push_back(LastInst->getOperand(0));
Cond.push_back(LastInst->getOperand(1));
}
}
static unsigned getBranchDisplacementBits(unsigned Opc) {
switch (Opc) {
default:
llvm_unreachable("unexpected opcode!");
case AArch64::B:
return BDisplacementBits;
case AArch64::TBNZW:
case AArch64::TBZW:
case AArch64::TBNZX:
case AArch64::TBZX:
return TBZDisplacementBits;
case AArch64::CBNZW:
case AArch64::CBZW:
case AArch64::CBNZX:
case AArch64::CBZX:
return CBZDisplacementBits;
case AArch64::Bcc:
return BCCDisplacementBits;
}
}
bool AArch64InstrInfo::isBranchOffsetInRange(unsigned BranchOp,
int64_t BrOffset) const {
unsigned Bits = getBranchDisplacementBits(BranchOp);
assert(Bits >= 3 && "max branch displacement must be enough to jump"
"over conditional branch expansion");
return isIntN(Bits, BrOffset / 4);
}
MachineBasicBlock *
AArch64InstrInfo::getBranchDestBlock(const MachineInstr &MI) const {
switch (MI.getOpcode()) {
default:
llvm_unreachable("unexpected opcode!");
case AArch64::B:
return MI.getOperand(0).getMBB();
case AArch64::TBZW:
case AArch64::TBNZW:
case AArch64::TBZX:
case AArch64::TBNZX:
return MI.getOperand(2).getMBB();
case AArch64::CBZW:
case AArch64::CBNZW:
case AArch64::CBZX:
case AArch64::CBNZX:
case AArch64::Bcc:
return MI.getOperand(1).getMBB();
}
}
void AArch64InstrInfo::insertIndirectBranch(MachineBasicBlock &MBB,
MachineBasicBlock &NewDestBB,
MachineBasicBlock &RestoreBB,
const DebugLoc &DL,
int64_t BrOffset,
RegScavenger *RS) const {
assert(RS && "RegScavenger required for long branching");
assert(MBB.empty() &&
"new block should be inserted for expanding unconditional branch");
assert(MBB.pred_size() == 1);
assert(RestoreBB.empty() &&
"restore block should be inserted for restoring clobbered registers");
auto buildIndirectBranch = [&](Register Reg, MachineBasicBlock &DestBB) {
// Offsets outside of the signed 33-bit range are not supported for ADRP +
// ADD.
if (!isInt<33>(BrOffset))
report_fatal_error(
"Branch offsets outside of the signed 33-bit range not supported");
BuildMI(MBB, MBB.end(), DL, get(AArch64::ADRP), Reg)
.addSym(DestBB.getSymbol(), AArch64II::MO_PAGE);
BuildMI(MBB, MBB.end(), DL, get(AArch64::ADDXri), Reg)
.addReg(Reg)
.addSym(DestBB.getSymbol(), AArch64II::MO_PAGEOFF | AArch64II::MO_NC)
.addImm(0);
BuildMI(MBB, MBB.end(), DL, get(AArch64::BR)).addReg(Reg);
};
RS->enterBasicBlockEnd(MBB);
// If X16 is unused, we can rely on the linker to insert a range extension
// thunk if NewDestBB is out of range of a single B instruction.
constexpr Register Reg = AArch64::X16;
if (!RS->isRegUsed(Reg)) {
insertUnconditionalBranch(MBB, &NewDestBB, DL);
RS->setRegUsed(Reg);
return;
}
// If there's a free register and it's worth inflating the code size,
// manually insert the indirect branch.
Register Scavenged = RS->FindUnusedReg(&AArch64::GPR64RegClass);
if (Scavenged != AArch64::NoRegister &&
MBB.getSectionID() == MBBSectionID::ColdSectionID) {
buildIndirectBranch(Scavenged, NewDestBB);
RS->setRegUsed(Scavenged);
return;
}
// Note: Spilling X16 briefly moves the stack pointer, making it incompatible
// with red zones.
AArch64FunctionInfo *AFI = MBB.getParent()->getInfo<AArch64FunctionInfo>();
if (!AFI || AFI->hasRedZone().value_or(true))
report_fatal_error(
"Unable to insert indirect branch inside function that has red zone");
// Otherwise, spill X16 and defer range extension to the linker.
BuildMI(MBB, MBB.end(), DL, get(AArch64::STRXpre))
.addReg(AArch64::SP, RegState::Define)
.addReg(Reg)
.addReg(AArch64::SP)
.addImm(-16);
BuildMI(MBB, MBB.end(), DL, get(AArch64::B)).addMBB(&RestoreBB);
BuildMI(RestoreBB, RestoreBB.end(), DL, get(AArch64::LDRXpost))
.addReg(AArch64::SP, RegState::Define)
.addReg(Reg, RegState::Define)
.addReg(AArch64::SP)
.addImm(16);
}
// Branch analysis.
bool AArch64InstrInfo::analyzeBranch(MachineBasicBlock &MBB,
MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const {
// If the block has no terminators, it just falls into the block after it.
MachineBasicBlock::iterator I = MBB.getLastNonDebugInstr();
if (I == MBB.end())
return false;
// Skip over SpeculationBarrierEndBB terminators
if (I->getOpcode() == AArch64::SpeculationBarrierISBDSBEndBB ||
I->getOpcode() == AArch64::SpeculationBarrierSBEndBB) {
--I;
}
if (!isUnpredicatedTerminator(*I))
return false;
// Get the last instruction in the block.
MachineInstr *LastInst = &*I;
// If there is only one terminator instruction, process it.
unsigned LastOpc = LastInst->getOpcode();
if (I == MBB.begin() || !isUnpredicatedTerminator(*--I)) {
if (isUncondBranchOpcode(LastOpc)) {
TBB = LastInst->getOperand(0).getMBB();
return false;
}
if (isCondBranchOpcode(LastOpc)) {
// Block ends with fall-through condbranch.
parseCondBranch(LastInst, TBB, Cond);
return false;
}
return true; // Can't handle indirect branch.
}
// Get the instruction before it if it is a terminator.
MachineInstr *SecondLastInst = &*I;
unsigned SecondLastOpc = SecondLastInst->getOpcode();
// If AllowModify is true and the block ends with two or more unconditional
// branches, delete all but the first unconditional branch.
if (AllowModify && isUncondBranchOpcode(LastOpc)) {
while (isUncondBranchOpcode(SecondLastOpc)) {
LastInst->eraseFromParent();
LastInst = SecondLastInst;
LastOpc = LastInst->getOpcode();
if (I == MBB.begin() || !isUnpredicatedTerminator(*--I)) {
// Return now the only terminator is an unconditional branch.
TBB = LastInst->getOperand(0).getMBB();
return false;
}
SecondLastInst = &*I;
SecondLastOpc = SecondLastInst->getOpcode();
}
}
// If we're allowed to modify and the block ends in a unconditional branch
// which could simply fallthrough, remove the branch. (Note: This case only
// matters when we can't understand the whole sequence, otherwise it's also
// handled by BranchFolding.cpp.)
if (AllowModify && isUncondBranchOpcode(LastOpc) &&
MBB.isLayoutSuccessor(getBranchDestBlock(*LastInst))) {
LastInst->eraseFromParent();
LastInst = SecondLastInst;
LastOpc = LastInst->getOpcode();
if (I == MBB.begin() || !isUnpredicatedTerminator(*--I)) {
assert(!isUncondBranchOpcode(LastOpc) &&
"unreachable unconditional branches removed above");
if (isCondBranchOpcode(LastOpc)) {
// Block ends with fall-through condbranch.
parseCondBranch(LastInst, TBB, Cond);
return false;
}
return true; // Can't handle indirect branch.
}
SecondLastInst = &*I;
SecondLastOpc = SecondLastInst->getOpcode();
}
// If there are three terminators, we don't know what sort of block this is.
if (SecondLastInst && I != MBB.begin() && isUnpredicatedTerminator(*--I))
return true;
// If the block ends with a B and a Bcc, handle it.
if (isCondBranchOpcode(SecondLastOpc) && isUncondBranchOpcode(LastOpc)) {
parseCondBranch(SecondLastInst, TBB, Cond);
FBB = LastInst->getOperand(0).getMBB();
return false;
}
// If the block ends with two unconditional branches, handle it. The second
// one is not executed, so remove it.
if (isUncondBranchOpcode(SecondLastOpc) && isUncondBranchOpcode(LastOpc)) {
TBB = SecondLastInst->getOperand(0).getMBB();
I = LastInst;
if (AllowModify)
I->eraseFromParent();
return false;
}
// ...likewise if it ends with an indirect branch followed by an unconditional
// branch.
if (isIndirectBranchOpcode(SecondLastOpc) && isUncondBranchOpcode(LastOpc)) {
I = LastInst;
if (AllowModify)
I->eraseFromParent();
return true;
}
// Otherwise, can't handle this.
return true;
}
bool AArch64InstrInfo::analyzeBranchPredicate(MachineBasicBlock &MBB,
MachineBranchPredicate &MBP,
bool AllowModify) const {
// For the moment, handle only a block which ends with a cb(n)zx followed by
// a fallthrough. Why this? Because it is a common form.
// TODO: Should we handle b.cc?
MachineBasicBlock::iterator I = MBB.getLastNonDebugInstr();
if (I == MBB.end())
return true;
// Skip over SpeculationBarrierEndBB terminators
if (I->getOpcode() == AArch64::SpeculationBarrierISBDSBEndBB ||
I->getOpcode() == AArch64::SpeculationBarrierSBEndBB) {
--I;
}
if (!isUnpredicatedTerminator(*I))
return true;
// Get the last instruction in the block.
MachineInstr *LastInst = &*I;
unsigned LastOpc = LastInst->getOpcode();
if (!isCondBranchOpcode(LastOpc))
return true;
switch (LastOpc) {
default:
return true;
case AArch64::CBZW:
case AArch64::CBZX:
case AArch64::CBNZW:
case AArch64::CBNZX:
break;
};
MBP.TrueDest = LastInst->getOperand(1).getMBB();
assert(MBP.TrueDest && "expected!");
MBP.FalseDest = MBB.getNextNode();
MBP.ConditionDef = nullptr;
MBP.SingleUseCondition = false;
MBP.LHS = LastInst->getOperand(0);
MBP.RHS = MachineOperand::CreateImm(0);
MBP.Predicate = LastOpc == AArch64::CBNZX ? MachineBranchPredicate::PRED_NE
: MachineBranchPredicate::PRED_EQ;
return false;
}
bool AArch64InstrInfo::reverseBranchCondition(
SmallVectorImpl<MachineOperand> &Cond) const {
if (Cond[0].getImm() != -1) {
// Regular Bcc
AArch64CC::CondCode CC = (AArch64CC::CondCode)(int)Cond[0].getImm();
Cond[0].setImm(AArch64CC::getInvertedCondCode(CC));
} else {
// Folded compare-and-branch
switch (Cond[1].getImm()) {
default:
llvm_unreachable("Unknown conditional branch!");
case AArch64::CBZW:
Cond[1].setImm(AArch64::CBNZW);
break;
case AArch64::CBNZW:
Cond[1].setImm(AArch64::CBZW);
break;
case AArch64::CBZX:
Cond[1].setImm(AArch64::CBNZX);
break;
case AArch64::CBNZX:
Cond[1].setImm(AArch64::CBZX);
break;
case AArch64::TBZW:
Cond[1].setImm(AArch64::TBNZW);
break;
case AArch64::TBNZW:
Cond[1].setImm(AArch64::TBZW);
break;
case AArch64::TBZX:
Cond[1].setImm(AArch64::TBNZX);
break;
case AArch64::TBNZX:
Cond[1].setImm(AArch64::TBZX);
break;
}
}
return false;
}
unsigned AArch64InstrInfo::removeBranch(MachineBasicBlock &MBB,
int *BytesRemoved) const {
MachineBasicBlock::iterator I = MBB.getLastNonDebugInstr();
if (I == MBB.end())
return 0;
if (!isUncondBranchOpcode(I->getOpcode()) &&
!isCondBranchOpcode(I->getOpcode()))
return 0;
// Remove the branch.
I->eraseFromParent();
I = MBB.end();
if (I == MBB.begin()) {
if (BytesRemoved)
*BytesRemoved = 4;
return 1;
}
--I;
if (!isCondBranchOpcode(I->getOpcode())) {
if (BytesRemoved)
*BytesRemoved = 4;
return 1;
}
// Remove the branch.
I->eraseFromParent();
if (BytesRemoved)
*BytesRemoved = 8;
return 2;
}
void AArch64InstrInfo::instantiateCondBranch(
MachineBasicBlock &MBB, const DebugLoc &DL, MachineBasicBlock *TBB,
ArrayRef<MachineOperand> Cond) const {
if (Cond[0].getImm() != -1) {
// Regular Bcc
BuildMI(&MBB, DL, get(AArch64::Bcc)).addImm(Cond[0].getImm()).addMBB(TBB);
} else {
// Folded compare-and-branch
// Note that we use addOperand instead of addReg to keep the flags.
const MachineInstrBuilder MIB =
BuildMI(&MBB, DL, get(Cond[1].getImm())).add(Cond[2]);
if (Cond.size() > 3)
MIB.addImm(Cond[3].getImm());
MIB.addMBB(TBB);
}
}
unsigned AArch64InstrInfo::insertBranch(
MachineBasicBlock &MBB, MachineBasicBlock *TBB, MachineBasicBlock *FBB,
ArrayRef<MachineOperand> Cond, const DebugLoc &DL, int *BytesAdded) const {
// Shouldn't be a fall through.
assert(TBB && "insertBranch must not be told to insert a fallthrough");
if (!FBB) {
if (Cond.empty()) // Unconditional branch?
BuildMI(&MBB, DL, get(AArch64::B)).addMBB(TBB);
else
instantiateCondBranch(MBB, DL, TBB, Cond);
if (BytesAdded)
*BytesAdded = 4;
return 1;
}
// Two-way conditional branch.
instantiateCondBranch(MBB, DL, TBB, Cond);
BuildMI(&MBB, DL, get(AArch64::B)).addMBB(FBB);
if (BytesAdded)
*BytesAdded = 8;
return 2;
}
// Find the original register that VReg is copied from.
static unsigned removeCopies(const MachineRegisterInfo &MRI, unsigned VReg) {
while (Register::isVirtualRegister(VReg)) {
const MachineInstr *DefMI = MRI.getVRegDef(VReg);
if (!DefMI->isFullCopy())
return VReg;
VReg = DefMI->getOperand(1).getReg();
}
return VReg;
}
// Determine if VReg is defined by an instruction that can be folded into a
// csel instruction. If so, return the folded opcode, and the replacement
// register.
static unsigned canFoldIntoCSel(const MachineRegisterInfo &MRI, unsigned VReg,
unsigned *NewVReg = nullptr) {
VReg = removeCopies(MRI, VReg);
if (!Register::isVirtualRegister(VReg))
return 0;
bool Is64Bit = AArch64::GPR64allRegClass.hasSubClassEq(MRI.getRegClass(VReg));
const MachineInstr *DefMI = MRI.getVRegDef(VReg);
unsigned Opc = 0;
unsigned SrcOpNum = 0;
switch (DefMI->getOpcode()) {
case AArch64::ADDSXri:
case AArch64::ADDSWri:
// if NZCV is used, do not fold.
if (DefMI->findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr,
true) == -1)
return 0;
// fall-through to ADDXri and ADDWri.
[[fallthrough]];
case AArch64::ADDXri:
case AArch64::ADDWri:
// add x, 1 -> csinc.
if (!DefMI->getOperand(2).isImm() || DefMI->getOperand(2).getImm() != 1 ||
DefMI->getOperand(3).getImm() != 0)
return 0;
SrcOpNum = 1;
Opc = Is64Bit ? AArch64::CSINCXr : AArch64::CSINCWr;
break;
case AArch64::ORNXrr:
case AArch64::ORNWrr: {
// not x -> csinv, represented as orn dst, xzr, src.
unsigned ZReg = removeCopies(MRI, DefMI->getOperand(1).getReg());
if (ZReg != AArch64::XZR && ZReg != AArch64::WZR)
return 0;
SrcOpNum = 2;
Opc = Is64Bit ? AArch64::CSINVXr : AArch64::CSINVWr;
break;
}
case AArch64::SUBSXrr:
case AArch64::SUBSWrr:
// if NZCV is used, do not fold.
if (DefMI->findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr,
true) == -1)
return 0;
// fall-through to SUBXrr and SUBWrr.
[[fallthrough]];
case AArch64::SUBXrr:
case AArch64::SUBWrr: {
// neg x -> csneg, represented as sub dst, xzr, src.
unsigned ZReg = removeCopies(MRI, DefMI->getOperand(1).getReg());
if (ZReg != AArch64::XZR && ZReg != AArch64::WZR)
return 0;
SrcOpNum = 2;
Opc = Is64Bit ? AArch64::CSNEGXr : AArch64::CSNEGWr;
break;
}
default:
return 0;
}
assert(Opc && SrcOpNum && "Missing parameters");
if (NewVReg)
*NewVReg = DefMI->getOperand(SrcOpNum).getReg();
return Opc;
}
bool AArch64InstrInfo::canInsertSelect(const MachineBasicBlock &MBB,
ArrayRef<MachineOperand> Cond,
Register DstReg, Register TrueReg,
Register FalseReg, int &CondCycles,
int &TrueCycles,
int &FalseCycles) const {
// Check register classes.
const MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
const TargetRegisterClass *RC =
RI.getCommonSubClass(MRI.getRegClass(TrueReg), MRI.getRegClass(FalseReg));
if (!RC)
return false;
// Also need to check the dest regclass, in case we're trying to optimize
// something like:
// %1(gpr) = PHI %2(fpr), bb1, %(fpr), bb2
if (!RI.getCommonSubClass(RC, MRI.getRegClass(DstReg)))
return false;
// Expanding cbz/tbz requires an extra cycle of latency on the condition.
unsigned ExtraCondLat = Cond.size() != 1;
// GPRs are handled by csel.
// FIXME: Fold in x+1, -x, and ~x when applicable.
if (AArch64::GPR64allRegClass.hasSubClassEq(RC) ||
AArch64::GPR32allRegClass.hasSubClassEq(RC)) {
// Single-cycle csel, csinc, csinv, and csneg.
CondCycles = 1 + ExtraCondLat;
TrueCycles = FalseCycles = 1;
if (canFoldIntoCSel(MRI, TrueReg))
TrueCycles = 0;
else if (canFoldIntoCSel(MRI, FalseReg))
FalseCycles = 0;
return true;
}
// Scalar floating point is handled by fcsel.
// FIXME: Form fabs, fmin, and fmax when applicable.
if (AArch64::FPR64RegClass.hasSubClassEq(RC) ||
AArch64::FPR32RegClass.hasSubClassEq(RC)) {
CondCycles = 5 + ExtraCondLat;
TrueCycles = FalseCycles = 2;
return true;
}
// Can't do vectors.
return false;
}
void AArch64InstrInfo::insertSelect(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
const DebugLoc &DL, Register DstReg,
ArrayRef<MachineOperand> Cond,
Register TrueReg, Register FalseReg) const {
MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
// Parse the condition code, see parseCondBranch() above.
AArch64CC::CondCode CC;
switch (Cond.size()) {
default:
llvm_unreachable("Unknown condition opcode in Cond");
case 1: // b.cc
CC = AArch64CC::CondCode(Cond[0].getImm());
break;
case 3: { // cbz/cbnz
// We must insert a compare against 0.
bool Is64Bit;
switch (Cond[1].getImm()) {
default:
llvm_unreachable("Unknown branch opcode in Cond");
case AArch64::CBZW:
Is64Bit = false;
CC = AArch64CC::EQ;
break;
case AArch64::CBZX:
Is64Bit = true;
CC = AArch64CC::EQ;
break;
case AArch64::CBNZW:
Is64Bit = false;
CC = AArch64CC::NE;
break;
case AArch64::CBNZX:
Is64Bit = true;
CC = AArch64CC::NE;
break;
}
Register SrcReg = Cond[2].getReg();
if (Is64Bit) {
// cmp reg, #0 is actually subs xzr, reg, #0.
MRI.constrainRegClass(SrcReg, &AArch64::GPR64spRegClass);
BuildMI(MBB, I, DL, get(AArch64::SUBSXri), AArch64::XZR)
.addReg(SrcReg)
.addImm(0)
.addImm(0);
} else {
MRI.constrainRegClass(SrcReg, &AArch64::GPR32spRegClass);
BuildMI(MBB, I, DL, get(AArch64::SUBSWri), AArch64::WZR)
.addReg(SrcReg)
.addImm(0)
.addImm(0);
}
break;
}
case 4: { // tbz/tbnz
// We must insert a tst instruction.
switch (Cond[1].getImm()) {
default:
llvm_unreachable("Unknown branch opcode in Cond");
case AArch64::TBZW:
case AArch64::TBZX:
CC = AArch64CC::EQ;
break;
case AArch64::TBNZW:
case AArch64::TBNZX:
CC = AArch64CC::NE;
break;
}
// cmp reg, #foo is actually ands xzr, reg, #1<<foo.
if (Cond[1].getImm() == AArch64::TBZW || Cond[1].getImm() == AArch64::TBNZW)
BuildMI(MBB, I, DL, get(AArch64::ANDSWri), AArch64::WZR)
.addReg(Cond[2].getReg())
.addImm(
AArch64_AM::encodeLogicalImmediate(1ull << Cond[3].getImm(), 32));
else
BuildMI(MBB, I, DL, get(AArch64::ANDSXri), AArch64::XZR)
.addReg(Cond[2].getReg())
.addImm(
AArch64_AM::encodeLogicalImmediate(1ull << Cond[3].getImm(), 64));
break;
}
}
unsigned Opc = 0;
const TargetRegisterClass *RC = nullptr;
bool TryFold = false;
if (MRI.constrainRegClass(DstReg, &AArch64::GPR64RegClass)) {
RC = &AArch64::GPR64RegClass;
Opc = AArch64::CSELXr;
TryFold = true;
} else if (MRI.constrainRegClass(DstReg, &AArch64::GPR32RegClass)) {
RC = &AArch64::GPR32RegClass;
Opc = AArch64::CSELWr;
TryFold = true;
} else if (MRI.constrainRegClass(DstReg, &AArch64::FPR64RegClass)) {
RC = &AArch64::FPR64RegClass;
Opc = AArch64::FCSELDrrr;
} else if (MRI.constrainRegClass(DstReg, &AArch64::FPR32RegClass)) {
RC = &AArch64::FPR32RegClass;
Opc = AArch64::FCSELSrrr;
}
assert(RC && "Unsupported regclass");
// Try folding simple instructions into the csel.
if (TryFold) {
unsigned NewVReg = 0;
unsigned FoldedOpc = canFoldIntoCSel(MRI, TrueReg, &NewVReg);
if (FoldedOpc) {
// The folded opcodes csinc, csinc and csneg apply the operation to
// FalseReg, so we need to invert the condition.
CC = AArch64CC::getInvertedCondCode(CC);
TrueReg = FalseReg;
} else
FoldedOpc = canFoldIntoCSel(MRI, FalseReg, &NewVReg);
// Fold the operation. Leave any dead instructions for DCE to clean up.
if (FoldedOpc) {
FalseReg = NewVReg;
Opc = FoldedOpc;
// The extends the live range of NewVReg.
MRI.clearKillFlags(NewVReg);
}
}
// Pull all virtual register into the appropriate class.
MRI.constrainRegClass(TrueReg, RC);
MRI.constrainRegClass(FalseReg, RC);
// Insert the csel.
BuildMI(MBB, I, DL, get(Opc), DstReg)
.addReg(TrueReg)
.addReg(FalseReg)
.addImm(CC);
}
// Return true if Imm can be loaded into a register by a "cheap" sequence of
// instructions. For now, "cheap" means at most two instructions.
static bool isCheapImmediate(const MachineInstr &MI, unsigned BitSize) {
if (BitSize == 32)
return true;
assert(BitSize == 64 && "Only bit sizes of 32 or 64 allowed");
uint64_t Imm = static_cast<uint64_t>(MI.getOperand(1).getImm());
SmallVector<AArch64_IMM::ImmInsnModel, 4> Is;
AArch64_IMM::expandMOVImm(Imm, BitSize, Is);
return Is.size() <= 2;
}
// FIXME: this implementation should be micro-architecture dependent, so a
// micro-architecture target hook should be introduced here in future.
bool AArch64InstrInfo::isAsCheapAsAMove(const MachineInstr &MI) const {
if (Subtarget.hasExynosCheapAsMoveHandling()) {
if (isExynosCheapAsMove(MI))
return true;
return MI.isAsCheapAsAMove();
}
switch (MI.getOpcode()) {
default:
return MI.isAsCheapAsAMove();
case AArch64::ADDWrs:
case AArch64::ADDXrs:
case AArch64::SUBWrs:
case AArch64::SUBXrs:
return Subtarget.hasALULSLFast() && MI.getOperand(3).getImm() <= 4;
// If MOVi32imm or MOVi64imm can be expanded into ORRWri or
// ORRXri, it is as cheap as MOV.
// Likewise if it can be expanded to MOVZ/MOVN/MOVK.
case AArch64::MOVi32imm:
return isCheapImmediate(MI, 32);
case AArch64::MOVi64imm:
return isCheapImmediate(MI, 64);
}
}
bool AArch64InstrInfo::isFalkorShiftExtFast(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
return false;
case AArch64::ADDWrs:
case AArch64::ADDXrs:
case AArch64::ADDSWrs:
case AArch64::ADDSXrs: {
unsigned Imm = MI.getOperand(3).getImm();
unsigned ShiftVal = AArch64_AM::getShiftValue(Imm);
if (ShiftVal == 0)
return true;
return AArch64_AM::getShiftType(Imm) == AArch64_AM::LSL && ShiftVal <= 5;
}
case AArch64::ADDWrx:
case AArch64::ADDXrx:
case AArch64::ADDXrx64:
case AArch64::ADDSWrx:
case AArch64::ADDSXrx:
case AArch64::ADDSXrx64: {
unsigned Imm = MI.getOperand(3).getImm();
switch (AArch64_AM::getArithExtendType(Imm)) {
default:
return false;
case AArch64_AM::UXTB:
case AArch64_AM::UXTH:
case AArch64_AM::UXTW:
case AArch64_AM::UXTX:
return AArch64_AM::getArithShiftValue(Imm) <= 4;
}
}
case AArch64::SUBWrs:
case AArch64::SUBSWrs: {
unsigned Imm = MI.getOperand(3).getImm();
unsigned ShiftVal = AArch64_AM::getShiftValue(Imm);
return ShiftVal == 0 ||
(AArch64_AM::getShiftType(Imm) == AArch64_AM::ASR && ShiftVal == 31);
}
case AArch64::SUBXrs:
case AArch64::SUBSXrs: {
unsigned Imm = MI.getOperand(3).getImm();
unsigned ShiftVal = AArch64_AM::getShiftValue(Imm);
return ShiftVal == 0 ||
(AArch64_AM::getShiftType(Imm) == AArch64_AM::ASR && ShiftVal == 63);
}
case AArch64::SUBWrx:
case AArch64::SUBXrx:
case AArch64::SUBXrx64:
case AArch64::SUBSWrx:
case AArch64::SUBSXrx:
case AArch64::SUBSXrx64: {
unsigned Imm = MI.getOperand(3).getImm();
switch (AArch64_AM::getArithExtendType(Imm)) {
default:
return false;
case AArch64_AM::UXTB:
case AArch64_AM::UXTH:
case AArch64_AM::UXTW:
case AArch64_AM::UXTX:
return AArch64_AM::getArithShiftValue(Imm) == 0;
}
}
case AArch64::LDRBBroW:
case AArch64::LDRBBroX:
case AArch64::LDRBroW:
case AArch64::LDRBroX:
case AArch64::LDRDroW:
case AArch64::LDRDroX:
case AArch64::LDRHHroW:
case AArch64::LDRHHroX:
case AArch64::LDRHroW:
case AArch64::LDRHroX:
case AArch64::LDRQroW:
case AArch64::LDRQroX:
case AArch64::LDRSBWroW:
case AArch64::LDRSBWroX:
case AArch64::LDRSBXroW:
case AArch64::LDRSBXroX:
case AArch64::LDRSHWroW:
case AArch64::LDRSHWroX:
case AArch64::LDRSHXroW:
case AArch64::LDRSHXroX:
case AArch64::LDRSWroW:
case AArch64::LDRSWroX:
case AArch64::LDRSroW:
case AArch64::LDRSroX:
case AArch64::LDRWroW:
case AArch64::LDRWroX:
case AArch64::LDRXroW:
case AArch64::LDRXroX:
case AArch64::PRFMroW:
case AArch64::PRFMroX:
case AArch64::STRBBroW:
case AArch64::STRBBroX:
case AArch64::STRBroW:
case AArch64::STRBroX:
case AArch64::STRDroW:
case AArch64::STRDroX:
case AArch64::STRHHroW:
case AArch64::STRHHroX:
case AArch64::STRHroW:
case AArch64::STRHroX:
case AArch64::STRQroW:
case AArch64::STRQroX:
case AArch64::STRSroW:
case AArch64::STRSroX:
case AArch64::STRWroW:
case AArch64::STRWroX:
case AArch64::STRXroW:
case AArch64::STRXroX: {
unsigned IsSigned = MI.getOperand(3).getImm();
return !IsSigned;
}
}
}
bool AArch64InstrInfo::isSEHInstruction(const MachineInstr &MI) {
unsigned Opc = MI.getOpcode();
switch (Opc) {
default:
return false;
case AArch64::SEH_StackAlloc:
case AArch64::SEH_SaveFPLR:
case AArch64::SEH_SaveFPLR_X:
case AArch64::SEH_SaveReg:
case AArch64::SEH_SaveReg_X:
case AArch64::SEH_SaveRegP:
case AArch64::SEH_SaveRegP_X:
case AArch64::SEH_SaveFReg:
case AArch64::SEH_SaveFReg_X:
case AArch64::SEH_SaveFRegP:
case AArch64::SEH_SaveFRegP_X:
case AArch64::SEH_SetFP:
case AArch64::SEH_AddFP:
case AArch64::SEH_Nop:
case AArch64::SEH_PrologEnd:
case AArch64::SEH_EpilogStart:
case AArch64::SEH_EpilogEnd:
case AArch64::SEH_PACSignLR:
case AArch64::SEH_SaveAnyRegQP:
case AArch64::SEH_SaveAnyRegQPX:
return true;
}
}
bool AArch64InstrInfo::isCoalescableExtInstr(const MachineInstr &MI,
Register &SrcReg, Register &DstReg,
unsigned &SubIdx) const {
switch (MI.getOpcode()) {
default:
return false;
case AArch64::SBFMXri: // aka sxtw
case AArch64::UBFMXri: // aka uxtw
// Check for the 32 -> 64 bit extension case, these instructions can do
// much more.
if (MI.getOperand(2).getImm() != 0 || MI.getOperand(3).getImm() != 31)
return false;
// This is a signed or unsigned 32 -> 64 bit extension.
SrcReg = MI.getOperand(1).getReg();
DstReg = MI.getOperand(0).getReg();
SubIdx = AArch64::sub_32;
return true;
}
}
bool AArch64InstrInfo::areMemAccessesTriviallyDisjoint(
const MachineInstr &MIa, const MachineInstr &MIb) const {
const TargetRegisterInfo *TRI = &getRegisterInfo();
const MachineOperand *BaseOpA = nullptr, *BaseOpB = nullptr;
int64_t OffsetA = 0, OffsetB = 0;
TypeSize WidthA(0, false), WidthB(0, false);
bool OffsetAIsScalable = false, OffsetBIsScalable = false;
assert(MIa.mayLoadOrStore() && "MIa must be a load or store.");
assert(MIb.mayLoadOrStore() && "MIb must be a load or store.");
if (MIa.hasUnmodeledSideEffects() || MIb.hasUnmodeledSideEffects() ||
MIa.hasOrderedMemoryRef() || MIb.hasOrderedMemoryRef())
return false;
// Retrieve the base, offset from the base and width. Width
// is the size of memory that is being loaded/stored (e.g. 1, 2, 4, 8). If
// base are identical, and the offset of a lower memory access +
// the width doesn't overlap the offset of a higher memory access,
// then the memory accesses are different.
// If OffsetAIsScalable and OffsetBIsScalable are both true, they
// are assumed to have the same scale (vscale).
if (getMemOperandWithOffsetWidth(MIa, BaseOpA, OffsetA, OffsetAIsScalable,
WidthA, TRI) &&
getMemOperandWithOffsetWidth(MIb, BaseOpB, OffsetB, OffsetBIsScalable,
WidthB, TRI)) {
if (BaseOpA->isIdenticalTo(*BaseOpB) &&
OffsetAIsScalable == OffsetBIsScalable) {
int LowOffset = OffsetA < OffsetB ? OffsetA : OffsetB;
int HighOffset = OffsetA < OffsetB ? OffsetB : OffsetA;
TypeSize LowWidth = (LowOffset == OffsetA) ? WidthA : WidthB;
if (LowWidth.isScalable() == OffsetAIsScalable &&
LowOffset + (int)LowWidth.getKnownMinValue() <= HighOffset)
return true;
}
}
return false;
}
bool AArch64InstrInfo::isSchedulingBoundary(const MachineInstr &MI,
const MachineBasicBlock *MBB,
const MachineFunction &MF) const {
if (TargetInstrInfo::isSchedulingBoundary(MI, MBB, MF))
return true;
// Do not move an instruction that can be recognized as a branch target.
if (hasBTISemantics(MI))
return true;
switch (MI.getOpcode()) {
case AArch64::HINT:
// CSDB hints are scheduling barriers.
if (MI.getOperand(0).getImm() == 0x14)
return true;
break;
case AArch64::DSB:
case AArch64::ISB:
// DSB and ISB also are scheduling barriers.
return true;
case AArch64::MSRpstatesvcrImm1:
// SMSTART and SMSTOP are also scheduling barriers.
return true;
default:;
}
if (isSEHInstruction(MI))
return true;
auto Next = std::next(MI.getIterator());
return Next != MBB->end() && Next->isCFIInstruction();
}
/// analyzeCompare - For a comparison instruction, return the source registers
/// in SrcReg and SrcReg2, and the value it compares against in CmpValue.
/// Return true if the comparison instruction can be analyzed.
bool AArch64InstrInfo::analyzeCompare(const MachineInstr &MI, Register &SrcReg,
Register &SrcReg2, int64_t &CmpMask,
int64_t &CmpValue) const {
// The first operand can be a frame index where we'd normally expect a
// register.
assert(MI.getNumOperands() >= 2 && "All AArch64 cmps should have 2 operands");
if (!MI.getOperand(1).isReg())
return false;
switch (MI.getOpcode()) {
default:
break;
case AArch64::PTEST_PP:
case AArch64::PTEST_PP_ANY:
SrcReg = MI.getOperand(0).getReg();
SrcReg2 = MI.getOperand(1).getReg();
// Not sure about the mask and value for now...
CmpMask = ~0;
CmpValue = 0;
return true;
case AArch64::SUBSWrr:
case AArch64::SUBSWrs:
case AArch64::SUBSWrx:
case AArch64::SUBSXrr:
case AArch64::SUBSXrs:
case AArch64::SUBSXrx:
case AArch64::ADDSWrr:
case AArch64::ADDSWrs:
case AArch64::ADDSWrx:
case AArch64::ADDSXrr:
case AArch64::ADDSXrs:
case AArch64::ADDSXrx:
// Replace SUBSWrr with SUBWrr if NZCV is not used.
SrcReg = MI.getOperand(1).getReg();
SrcReg2 = MI.getOperand(2).getReg();
CmpMask = ~0;
CmpValue = 0;
return true;
case AArch64::SUBSWri:
case AArch64::ADDSWri:
case AArch64::SUBSXri:
case AArch64::ADDSXri:
SrcReg = MI.getOperand(1).getReg();
SrcReg2 = 0;
CmpMask = ~0;
CmpValue = MI.getOperand(2).getImm();
return true;
case AArch64::ANDSWri:
case AArch64::ANDSXri:
// ANDS does not use the same encoding scheme as the others xxxS
// instructions.
SrcReg = MI.getOperand(1).getReg();
SrcReg2 = 0;
CmpMask = ~0;
CmpValue = AArch64_AM::decodeLogicalImmediate(
MI.getOperand(2).getImm(),
MI.getOpcode() == AArch64::ANDSWri ? 32 : 64);
return true;
}
return false;
}
static bool UpdateOperandRegClass(MachineInstr &Instr) {
MachineBasicBlock *MBB = Instr.getParent();
assert(MBB && "Can't get MachineBasicBlock here");
MachineFunction *MF = MBB->getParent();
assert(MF && "Can't get MachineFunction here");
const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
MachineRegisterInfo *MRI = &MF->getRegInfo();
for (unsigned OpIdx = 0, EndIdx = Instr.getNumOperands(); OpIdx < EndIdx;
++OpIdx) {
MachineOperand &MO = Instr.getOperand(OpIdx);
const TargetRegisterClass *OpRegCstraints =
Instr.getRegClassConstraint(OpIdx, TII, TRI);
// If there's no constraint, there's nothing to do.
if (!OpRegCstraints)
continue;
// If the operand is a frame index, there's nothing to do here.
// A frame index operand will resolve correctly during PEI.
if (MO.isFI())
continue;
assert(MO.isReg() &&
"Operand has register constraints without being a register!");
Register Reg = MO.getReg();
if (Reg.isPhysical()) {
if (!OpRegCstraints->contains(Reg))
return false;
} else if (!OpRegCstraints->hasSubClassEq(MRI->getRegClass(Reg)) &&
!MRI->constrainRegClass(Reg, OpRegCstraints))
return false;
}
return true;
}
/// Return the opcode that does not set flags when possible - otherwise
/// return the original opcode. The caller is responsible to do the actual
/// substitution and legality checking.
static unsigned convertToNonFlagSettingOpc(const MachineInstr &MI) {
// Don't convert all compare instructions, because for some the zero register
// encoding becomes the sp register.
bool MIDefinesZeroReg = false;
if (MI.definesRegister(AArch64::WZR, /*TRI=*/nullptr) ||
MI.definesRegister(AArch64::XZR, /*TRI=*/nullptr))
MIDefinesZeroReg = true;
switch (MI.getOpcode()) {
default:
return MI.getOpcode();
case AArch64::ADDSWrr:
return AArch64::ADDWrr;
case AArch64::ADDSWri:
return MIDefinesZeroReg ? AArch64::ADDSWri : AArch64::ADDWri;
case AArch64::ADDSWrs:
return MIDefinesZeroReg ? AArch64::ADDSWrs : AArch64::ADDWrs;
case AArch64::ADDSWrx:
return AArch64::ADDWrx;
case AArch64::ADDSXrr:
return AArch64::ADDXrr;
case AArch64::ADDSXri:
return MIDefinesZeroReg ? AArch64::ADDSXri : AArch64::ADDXri;
case AArch64::ADDSXrs:
return MIDefinesZeroReg ? AArch64::ADDSXrs : AArch64::ADDXrs;
case AArch64::ADDSXrx:
return AArch64::ADDXrx;
case AArch64::SUBSWrr:
return AArch64::SUBWrr;
case AArch64::SUBSWri:
return MIDefinesZeroReg ? AArch64::SUBSWri : AArch64::SUBWri;
case AArch64::SUBSWrs:
return MIDefinesZeroReg ? AArch64::SUBSWrs : AArch64::SUBWrs;
case AArch64::SUBSWrx:
return AArch64::SUBWrx;
case AArch64::SUBSXrr:
return AArch64::SUBXrr;
case AArch64::SUBSXri:
return MIDefinesZeroReg ? AArch64::SUBSXri : AArch64::SUBXri;
case AArch64::SUBSXrs:
return MIDefinesZeroReg ? AArch64::SUBSXrs : AArch64::SUBXrs;
case AArch64::SUBSXrx:
return AArch64::SUBXrx;
}
}
enum AccessKind { AK_Write = 0x01, AK_Read = 0x10, AK_All = 0x11 };
/// True when condition flags are accessed (either by writing or reading)
/// on the instruction trace starting at From and ending at To.
///
/// Note: If From and To are from different blocks it's assumed CC are accessed
/// on the path.
static bool areCFlagsAccessedBetweenInstrs(
MachineBasicBlock::iterator From, MachineBasicBlock::iterator To,
const TargetRegisterInfo *TRI, const AccessKind AccessToCheck = AK_All) {
// Early exit if To is at the beginning of the BB.
if (To == To->getParent()->begin())
return true;
// Check whether the instructions are in the same basic block
// If not, assume the condition flags might get modified somewhere.
if (To->getParent() != From->getParent())
return true;
// From must be above To.
assert(std::any_of(
++To.getReverse(), To->getParent()->rend(),
[From](MachineInstr &MI) { return MI.getIterator() == From; }));
// We iterate backward starting at \p To until we hit \p From.
for (const MachineInstr &Instr :
instructionsWithoutDebug(++To.getReverse(), From.getReverse())) {
if (((AccessToCheck & AK_Write) &&
Instr.modifiesRegister(AArch64::NZCV, TRI)) ||
((AccessToCheck & AK_Read) && Instr.readsRegister(AArch64::NZCV, TRI)))
return true;
}
return false;
}
/// optimizePTestInstr - Attempt to remove a ptest of a predicate-generating
/// operation which could set the flags in an identical manner
bool AArch64InstrInfo::optimizePTestInstr(
MachineInstr *PTest, unsigned MaskReg, unsigned PredReg,
const MachineRegisterInfo *MRI) const {
auto *Mask = MRI->getUniqueVRegDef(MaskReg);
auto *Pred = MRI->getUniqueVRegDef(PredReg);
auto NewOp = Pred->getOpcode();
bool OpChanged = false;
unsigned MaskOpcode = Mask->getOpcode();
unsigned PredOpcode = Pred->getOpcode();
bool PredIsPTestLike = isPTestLikeOpcode(PredOpcode);
bool PredIsWhileLike = isWhileOpcode(PredOpcode);
if (isPTrueOpcode(MaskOpcode) && (PredIsPTestLike || PredIsWhileLike) &&
getElementSizeForOpcode(MaskOpcode) ==
getElementSizeForOpcode(PredOpcode) &&
Mask->getOperand(1).getImm() == 31) {
// For PTEST(PTRUE_ALL, WHILE), if the element size matches, the PTEST is
// redundant since WHILE performs an implicit PTEST with an all active
// mask. Must be an all active predicate of matching element size.
// For PTEST(PTRUE_ALL, PTEST_LIKE), the PTEST is redundant if the
// PTEST_LIKE instruction uses the same all active mask and the element
// size matches. If the PTEST has a condition of any then it is always
// redundant.
if (PredIsPTestLike) {
auto PTestLikeMask = MRI->getUniqueVRegDef(Pred->getOperand(1).getReg());
if (Mask != PTestLikeMask && PTest->getOpcode() != AArch64::PTEST_PP_ANY)
return false;
}
// Fallthough to simply remove the PTEST.
} else if ((Mask == Pred) && (PredIsPTestLike || PredIsWhileLike) &&
PTest->getOpcode() == AArch64::PTEST_PP_ANY) {
// For PTEST(PG, PG), PTEST is redundant when PG is the result of an
// instruction that sets the flags as PTEST would. This is only valid when
// the condition is any.
// Fallthough to simply remove the PTEST.
} else if (PredIsPTestLike) {
// For PTEST(PG, PTEST_LIKE(PG, ...)), the PTEST is redundant since the
// flags are set based on the same mask 'PG', but PTEST_LIKE must operate
// on 8-bit predicates like the PTEST. Otherwise, for instructions like
// compare that also support 16/32/64-bit predicates, the implicit PTEST
// performed by the compare could consider fewer lanes for these element
// sizes.
//
// For example, consider
//
// ptrue p0.b ; P0=1111-1111-1111-1111
// index z0.s, #0, #1 ; Z0=<0,1,2,3>
// index z1.s, #1, #1 ; Z1=<1,2,3,4>
// cmphi p1.s, p0/z, z1.s, z0.s ; P1=0001-0001-0001-0001
// ; ^ last active
// ptest p0, p1.b ; P1=0001-0001-0001-0001
// ; ^ last active
//
// where the compare generates a canonical all active 32-bit predicate
// (equivalent to 'ptrue p1.s, all'). The implicit PTEST sets the last
// active flag, whereas the PTEST instruction with the same mask doesn't.
// For PTEST_ANY this doesn't apply as the flags in this case would be
// identical regardless of element size.
auto PTestLikeMask = MRI->getUniqueVRegDef(Pred->getOperand(1).getReg());
uint64_t PredElementSize = getElementSizeForOpcode(PredOpcode);
if ((Mask != PTestLikeMask) ||
(PredElementSize != AArch64::ElementSizeB &&
PTest->getOpcode() != AArch64::PTEST_PP_ANY))
return false;
// Fallthough to simply remove the PTEST.
} else {
// If OP in PTEST(PG, OP(PG, ...)) has a flag-setting variant change the
// opcode so the PTEST becomes redundant.
switch (PredOpcode) {
case AArch64::AND_PPzPP:
case AArch64::BIC_PPzPP:
case AArch64::EOR_PPzPP:
case AArch64::NAND_PPzPP:
case AArch64::NOR_PPzPP:
case AArch64::ORN_PPzPP:
case AArch64::ORR_PPzPP:
case AArch64::BRKA_PPzP:
case AArch64::BRKPA_PPzPP:
case AArch64::BRKB_PPzP:
case AArch64::BRKPB_PPzPP:
case AArch64::RDFFR_PPz: {
// Check to see if our mask is the same. If not the resulting flag bits
// may be different and we can't remove the ptest.
auto *PredMask = MRI->getUniqueVRegDef(Pred->getOperand(1).getReg());
if (Mask != PredMask)
return false;
break;
}
case AArch64::BRKN_PPzP: {
// BRKN uses an all active implicit mask to set flags unlike the other
// flag-setting instructions.
// PTEST(PTRUE_B(31), BRKN(PG, A, B)) -> BRKNS(PG, A, B).
if ((MaskOpcode != AArch64::PTRUE_B) ||
(Mask->getOperand(1).getImm() != 31))
return false;
break;
}
case AArch64::PTRUE_B:
// PTEST(OP=PTRUE_B(A), OP) -> PTRUES_B(A)
break;
default:
// Bail out if we don't recognize the input
return false;
}
NewOp = convertToFlagSettingOpc(PredOpcode);
OpChanged = true;
}
const TargetRegisterInfo *TRI = &getRegisterInfo();
// If another instruction between Pred and PTest accesses flags, don't remove
// the ptest or update the earlier instruction to modify them.
if (areCFlagsAccessedBetweenInstrs(Pred, PTest, TRI))
return false;
// If we pass all the checks, it's safe to remove the PTEST and use the flags
// as they are prior to PTEST. Sometimes this requires the tested PTEST
// operand to be replaced with an equivalent instruction that also sets the
// flags.
Pred->setDesc(get(NewOp));
PTest->eraseFromParent();
if (OpChanged) {
bool succeeded = UpdateOperandRegClass(*Pred);
(void)succeeded;
assert(succeeded && "Operands have incompatible register classes!");
Pred->addRegisterDefined(AArch64::NZCV, TRI);
}
// Ensure that the flags def is live.
if (Pred->registerDefIsDead(AArch64::NZCV, TRI)) {
unsigned i = 0, e = Pred->getNumOperands();
for (; i != e; ++i) {
MachineOperand &MO = Pred->getOperand(i);
if (MO.isReg() && MO.isDef() && MO.getReg() == AArch64::NZCV) {
MO.setIsDead(false);
break;
}
}
}
return true;
}
/// Try to optimize a compare instruction. A compare instruction is an
/// instruction which produces AArch64::NZCV. It can be truly compare
/// instruction
/// when there are no uses of its destination register.
///
/// The following steps are tried in order:
/// 1. Convert CmpInstr into an unconditional version.
/// 2. Remove CmpInstr if above there is an instruction producing a needed
/// condition code or an instruction which can be converted into such an
/// instruction.
/// Only comparison with zero is supported.
bool AArch64InstrInfo::optimizeCompareInstr(
MachineInstr &CmpInstr, Register SrcReg, Register SrcReg2, int64_t CmpMask,
int64_t CmpValue, const MachineRegisterInfo *MRI) const {
assert(CmpInstr.getParent());
assert(MRI);
// Replace SUBSWrr with SUBWrr if NZCV is not used.
int DeadNZCVIdx =
CmpInstr.findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr, true);
if (DeadNZCVIdx != -1) {
if (CmpInstr.definesRegister(AArch64::WZR, /*TRI=*/nullptr) ||
CmpInstr.definesRegister(AArch64::XZR, /*TRI=*/nullptr)) {
CmpInstr.eraseFromParent();
return true;
}
unsigned Opc = CmpInstr.getOpcode();
unsigned NewOpc = convertToNonFlagSettingOpc(CmpInstr);
if (NewOpc == Opc)
return false;
const MCInstrDesc &MCID = get(NewOpc);
CmpInstr.setDesc(MCID);
CmpInstr.removeOperand(DeadNZCVIdx);
bool succeeded = UpdateOperandRegClass(CmpInstr);
(void)succeeded;
assert(succeeded && "Some operands reg class are incompatible!");
return true;
}
if (CmpInstr.getOpcode() == AArch64::PTEST_PP ||
CmpInstr.getOpcode() == AArch64::PTEST_PP_ANY)
return optimizePTestInstr(&CmpInstr, SrcReg, SrcReg2, MRI);
if (SrcReg2 != 0)
return false;
// CmpInstr is a Compare instruction if destination register is not used.
if (!MRI->use_nodbg_empty(CmpInstr.getOperand(0).getReg()))
return false;
if (CmpValue == 0 && substituteCmpToZero(CmpInstr, SrcReg, *MRI))
return true;
return (CmpValue == 0 || CmpValue == 1) &&
removeCmpToZeroOrOne(CmpInstr, SrcReg, CmpValue, *MRI);
}
/// Get opcode of S version of Instr.
/// If Instr is S version its opcode is returned.
/// AArch64::INSTRUCTION_LIST_END is returned if Instr does not have S version
/// or we are not interested in it.
static unsigned sForm(MachineInstr &Instr) {
switch (Instr.getOpcode()) {
default:
return AArch64::INSTRUCTION_LIST_END;
case AArch64::ADDSWrr:
case AArch64::ADDSWri:
case AArch64::ADDSXrr:
case AArch64::ADDSXri:
case AArch64::SUBSWrr:
case AArch64::SUBSWri:
case AArch64::SUBSXrr:
case AArch64::SUBSXri:
return Instr.getOpcode();
case AArch64::ADDWrr:
return AArch64::ADDSWrr;
case AArch64::ADDWri:
return AArch64::ADDSWri;
case AArch64::ADDXrr:
return AArch64::ADDSXrr;
case AArch64::ADDXri:
return AArch64::ADDSXri;
case AArch64::ADCWr:
return AArch64::ADCSWr;
case AArch64::ADCXr:
return AArch64::ADCSXr;
case AArch64::SUBWrr:
return AArch64::SUBSWrr;
case AArch64::SUBWri:
return AArch64::SUBSWri;
case AArch64::SUBXrr:
return AArch64::SUBSXrr;
case AArch64::SUBXri:
return AArch64::SUBSXri;
case AArch64::SBCWr:
return AArch64::SBCSWr;
case AArch64::SBCXr:
return AArch64::SBCSXr;
case AArch64::ANDWri:
return AArch64::ANDSWri;
case AArch64::ANDXri:
return AArch64::ANDSXri;
}
}
/// Check if AArch64::NZCV should be alive in successors of MBB.
static bool areCFlagsAliveInSuccessors(const MachineBasicBlock *MBB) {
for (auto *BB : MBB->successors())
if (BB->isLiveIn(AArch64::NZCV))
return true;
return false;
}
/// \returns The condition code operand index for \p Instr if it is a branch
/// or select and -1 otherwise.
static int
findCondCodeUseOperandIdxForBranchOrSelect(const MachineInstr &Instr) {
switch (Instr.getOpcode()) {
default:
return -1;
case AArch64::Bcc: {
int Idx = Instr.findRegisterUseOperandIdx(AArch64::NZCV, /*TRI=*/nullptr);
assert(Idx >= 2);
return Idx - 2;
}
case AArch64::CSINVWr:
case AArch64::CSINVXr:
case AArch64::CSINCWr:
case AArch64::CSINCXr:
case AArch64::CSELWr:
case AArch64::CSELXr:
case AArch64::CSNEGWr:
case AArch64::CSNEGXr:
case AArch64::FCSELSrrr:
case AArch64::FCSELDrrr: {
int Idx = Instr.findRegisterUseOperandIdx(AArch64::NZCV, /*TRI=*/nullptr);
assert(Idx >= 1);
return Idx - 1;
}
}
}
/// Find a condition code used by the instruction.
/// Returns AArch64CC::Invalid if either the instruction does not use condition
/// codes or we don't optimize CmpInstr in the presence of such instructions.
static AArch64CC::CondCode findCondCodeUsedByInstr(const MachineInstr &Instr) {
int CCIdx = findCondCodeUseOperandIdxForBranchOrSelect(Instr);
return CCIdx >= 0 ? static_cast<AArch64CC::CondCode>(
Instr.getOperand(CCIdx).getImm())
: AArch64CC::Invalid;
}
static UsedNZCV getUsedNZCV(AArch64CC::CondCode CC) {
assert(CC != AArch64CC::Invalid);
UsedNZCV UsedFlags;
switch (CC) {
default:
break;
case AArch64CC::EQ: // Z set
case AArch64CC::NE: // Z clear
UsedFlags.Z = true;
break;
case AArch64CC::HI: // Z clear and C set
case AArch64CC::LS: // Z set or C clear
UsedFlags.Z = true;
[[fallthrough]];
case AArch64CC::HS: // C set
case AArch64CC::LO: // C clear
UsedFlags.C = true;
break;
case AArch64CC::MI: // N set
case AArch64CC::PL: // N clear
UsedFlags.N = true;
break;
case AArch64CC::VS: // V set
case AArch64CC::VC: // V clear
UsedFlags.V = true;
break;
case AArch64CC::GT: // Z clear, N and V the same
case AArch64CC::LE: // Z set, N and V differ
UsedFlags.Z = true;
[[fallthrough]];
case AArch64CC::GE: // N and V the same
case AArch64CC::LT: // N and V differ
UsedFlags.N = true;
UsedFlags.V = true;
break;
}
return UsedFlags;
}
/// \returns Conditions flags used after \p CmpInstr in its MachineBB if NZCV
/// flags are not alive in successors of the same \p CmpInstr and \p MI parent.
/// \returns std::nullopt otherwise.
///
/// Collect instructions using that flags in \p CCUseInstrs if provided.
std::optional<UsedNZCV>
llvm::examineCFlagsUse(MachineInstr &MI, MachineInstr &CmpInstr,
const TargetRegisterInfo &TRI,
SmallVectorImpl<MachineInstr *> *CCUseInstrs) {
MachineBasicBlock *CmpParent = CmpInstr.getParent();
if (MI.getParent() != CmpParent)
return std::nullopt;
if (areCFlagsAliveInSuccessors(CmpParent))
return std::nullopt;
UsedNZCV NZCVUsedAfterCmp;
for (MachineInstr &Instr : instructionsWithoutDebug(
std::next(CmpInstr.getIterator()), CmpParent->instr_end())) {
if (Instr.readsRegister(AArch64::NZCV, &TRI)) {
AArch64CC::CondCode CC = findCondCodeUsedByInstr(Instr);
if (CC == AArch64CC::Invalid) // Unsupported conditional instruction
return std::nullopt;
NZCVUsedAfterCmp |= getUsedNZCV(CC);
if (CCUseInstrs)
CCUseInstrs->push_back(&Instr);
}
if (Instr.modifiesRegister(AArch64::NZCV, &TRI))
break;
}
return NZCVUsedAfterCmp;
}
static bool isADDSRegImm(unsigned Opcode) {
return Opcode == AArch64::ADDSWri || Opcode == AArch64::ADDSXri;
}
static bool isSUBSRegImm(unsigned Opcode) {
return Opcode == AArch64::SUBSWri || Opcode == AArch64::SUBSXri;
}
/// Check if CmpInstr can be substituted by MI.
///
/// CmpInstr can be substituted:
/// - CmpInstr is either 'ADDS %vreg, 0' or 'SUBS %vreg, 0'
/// - and, MI and CmpInstr are from the same MachineBB
/// - and, condition flags are not alive in successors of the CmpInstr parent
/// - and, if MI opcode is the S form there must be no defs of flags between
/// MI and CmpInstr
/// or if MI opcode is not the S form there must be neither defs of flags
/// nor uses of flags between MI and CmpInstr.
/// - and, if C/V flags are not used after CmpInstr
/// or if N flag is used but MI produces poison value if signed overflow
/// occurs.
static bool canInstrSubstituteCmpInstr(MachineInstr &MI, MachineInstr &CmpInstr,
const TargetRegisterInfo &TRI) {
// NOTE this assertion guarantees that MI.getOpcode() is add or subtraction
// that may or may not set flags.
assert(sForm(MI) != AArch64::INSTRUCTION_LIST_END);
const unsigned CmpOpcode = CmpInstr.getOpcode();
if (!isADDSRegImm(CmpOpcode) && !isSUBSRegImm(CmpOpcode))
return false;
assert((CmpInstr.getOperand(2).isImm() &&
CmpInstr.getOperand(2).getImm() == 0) &&
"Caller guarantees that CmpInstr compares with constant 0");
std::optional<UsedNZCV> NZVCUsed = examineCFlagsUse(MI, CmpInstr, TRI);
if (!NZVCUsed || NZVCUsed->C)
return false;
// CmpInstr is either 'ADDS %vreg, 0' or 'SUBS %vreg, 0', and MI is either
// '%vreg = add ...' or '%vreg = sub ...'.
// Condition flag V is used to indicate signed overflow.
// 1) MI and CmpInstr set N and V to the same value.
// 2) If MI is add/sub with no-signed-wrap, it produces a poison value when
// signed overflow occurs, so CmpInstr could still be simplified away.
if (NZVCUsed->V && !MI.getFlag(MachineInstr::NoSWrap))
return false;
AccessKind AccessToCheck = AK_Write;
if (sForm(MI) != MI.getOpcode())
AccessToCheck = AK_All;
return !areCFlagsAccessedBetweenInstrs(&MI, &CmpInstr, &TRI, AccessToCheck);
}
/// Substitute an instruction comparing to zero with another instruction
/// which produces needed condition flags.
///
/// Return true on success.
bool AArch64InstrInfo::substituteCmpToZero(
MachineInstr &CmpInstr, unsigned SrcReg,
const MachineRegisterInfo &MRI) const {
// Get the unique definition of SrcReg.
MachineInstr *MI = MRI.getUniqueVRegDef(SrcReg);
if (!MI)
return false;
const TargetRegisterInfo &TRI = getRegisterInfo();
unsigned NewOpc = sForm(*MI);
if (NewOpc == AArch64::INSTRUCTION_LIST_END)
return false;
if (!canInstrSubstituteCmpInstr(*MI, CmpInstr, TRI))
return false;
// Update the instruction to set NZCV.
MI->setDesc(get(NewOpc));
CmpInstr.eraseFromParent();
bool succeeded = UpdateOperandRegClass(*MI);
(void)succeeded;
assert(succeeded && "Some operands reg class are incompatible!");
MI->addRegisterDefined(AArch64::NZCV, &TRI);
return true;
}
/// \returns True if \p CmpInstr can be removed.
///
/// \p IsInvertCC is true if, after removing \p CmpInstr, condition
/// codes used in \p CCUseInstrs must be inverted.
static bool canCmpInstrBeRemoved(MachineInstr &MI, MachineInstr &CmpInstr,
int CmpValue, const TargetRegisterInfo &TRI,
SmallVectorImpl<MachineInstr *> &CCUseInstrs,
bool &IsInvertCC) {
assert((CmpValue == 0 || CmpValue == 1) &&
"Only comparisons to 0 or 1 considered for removal!");
// MI is 'CSINCWr %vreg, wzr, wzr, <cc>' or 'CSINCXr %vreg, xzr, xzr, <cc>'
unsigned MIOpc = MI.getOpcode();
if (MIOpc == AArch64::CSINCWr) {
if (MI.getOperand(1).getReg() != AArch64::WZR ||
MI.getOperand(2).getReg() != AArch64::WZR)
return false;
} else if (MIOpc == AArch64::CSINCXr) {
if (MI.getOperand(1).getReg() != AArch64::XZR ||
MI.getOperand(2).getReg() != AArch64::XZR)
return false;
} else {
return false;
}
AArch64CC::CondCode MICC = findCondCodeUsedByInstr(MI);
if (MICC == AArch64CC::Invalid)
return false;
// NZCV needs to be defined
if (MI.findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr, true) != -1)
return false;
// CmpInstr is 'ADDS %vreg, 0' or 'SUBS %vreg, 0' or 'SUBS %vreg, 1'
const unsigned CmpOpcode = CmpInstr.getOpcode();
bool IsSubsRegImm = isSUBSRegImm(CmpOpcode);
if (CmpValue && !IsSubsRegImm)
return false;
if (!CmpValue && !IsSubsRegImm && !isADDSRegImm(CmpOpcode))
return false;
// MI conditions allowed: eq, ne, mi, pl
UsedNZCV MIUsedNZCV = getUsedNZCV(MICC);
if (MIUsedNZCV.C || MIUsedNZCV.V)
return false;
std::optional<UsedNZCV> NZCVUsedAfterCmp =
examineCFlagsUse(MI, CmpInstr, TRI, &CCUseInstrs);
// Condition flags are not used in CmpInstr basic block successors and only
// Z or N flags allowed to be used after CmpInstr within its basic block
if (!NZCVUsedAfterCmp || NZCVUsedAfterCmp->C || NZCVUsedAfterCmp->V)
return false;
// Z or N flag used after CmpInstr must correspond to the flag used in MI
if ((MIUsedNZCV.Z && NZCVUsedAfterCmp->N) ||
(MIUsedNZCV.N && NZCVUsedAfterCmp->Z))
return false;
// If CmpInstr is comparison to zero MI conditions are limited to eq, ne
if (MIUsedNZCV.N && !CmpValue)
return false;
// There must be no defs of flags between MI and CmpInstr
if (areCFlagsAccessedBetweenInstrs(&MI, &CmpInstr, &TRI, AK_Write))
return false;
// Condition code is inverted in the following cases:
// 1. MI condition is ne; CmpInstr is 'ADDS %vreg, 0' or 'SUBS %vreg, 0'
// 2. MI condition is eq, pl; CmpInstr is 'SUBS %vreg, 1'
IsInvertCC = (CmpValue && (MICC == AArch64CC::EQ || MICC == AArch64CC::PL)) ||
(!CmpValue && MICC == AArch64CC::NE);
return true;
}
/// Remove comparison in csinc-cmp sequence
///
/// Examples:
/// 1. \code
/// csinc w9, wzr, wzr, ne
/// cmp w9, #0
/// b.eq
/// \endcode
/// to
/// \code
/// csinc w9, wzr, wzr, ne
/// b.ne
/// \endcode
///
/// 2. \code
/// csinc x2, xzr, xzr, mi
/// cmp x2, #1
/// b.pl
/// \endcode
/// to
/// \code
/// csinc x2, xzr, xzr, mi
/// b.pl
/// \endcode
///
/// \param CmpInstr comparison instruction
/// \return True when comparison removed
bool AArch64InstrInfo::removeCmpToZeroOrOne(
MachineInstr &CmpInstr, unsigned SrcReg, int CmpValue,
const MachineRegisterInfo &MRI) const {
MachineInstr *MI = MRI.getUniqueVRegDef(SrcReg);
if (!MI)
return false;
const TargetRegisterInfo &TRI = getRegisterInfo();
SmallVector<MachineInstr *, 4> CCUseInstrs;
bool IsInvertCC = false;
if (!canCmpInstrBeRemoved(*MI, CmpInstr, CmpValue, TRI, CCUseInstrs,
IsInvertCC))
return false;
// Make transformation
CmpInstr.eraseFromParent();
if (IsInvertCC) {
// Invert condition codes in CmpInstr CC users
for (MachineInstr *CCUseInstr : CCUseInstrs) {
int Idx = findCondCodeUseOperandIdxForBranchOrSelect(*CCUseInstr);
assert(Idx >= 0 && "Unexpected instruction using CC.");
MachineOperand &CCOperand = CCUseInstr->getOperand(Idx);
AArch64CC::CondCode CCUse = AArch64CC::getInvertedCondCode(
static_cast<AArch64CC::CondCode>(CCOperand.getImm()));
CCOperand.setImm(CCUse);
}
}
return true;
}
bool AArch64InstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
if (MI.getOpcode() != TargetOpcode::LOAD_STACK_GUARD &&
MI.getOpcode() != AArch64::CATCHRET)
return false;
MachineBasicBlock &MBB = *MI.getParent();
auto &Subtarget = MBB.getParent()->getSubtarget<AArch64Subtarget>();
auto TRI = Subtarget.getRegisterInfo();
DebugLoc DL = MI.getDebugLoc();
if (MI.getOpcode() == AArch64::CATCHRET) {
// Skip to the first instruction before the epilog.
const TargetInstrInfo *TII =
MBB.getParent()->getSubtarget().getInstrInfo();
MachineBasicBlock *TargetMBB = MI.getOperand(0).getMBB();
auto MBBI = MachineBasicBlock::iterator(MI);
MachineBasicBlock::iterator FirstEpilogSEH = std::prev(MBBI);
while (FirstEpilogSEH->getFlag(MachineInstr::FrameDestroy) &&
FirstEpilogSEH != MBB.begin())
FirstEpilogSEH = std::prev(FirstEpilogSEH);
if (FirstEpilogSEH != MBB.begin())
FirstEpilogSEH = std::next(FirstEpilogSEH);
BuildMI(MBB, FirstEpilogSEH, DL, TII->get(AArch64::ADRP))
.addReg(AArch64::X0, RegState::Define)
.addMBB(TargetMBB);
BuildMI(MBB, FirstEpilogSEH, DL, TII->get(AArch64::ADDXri))
.addReg(AArch64::X0, RegState::Define)
.addReg(AArch64::X0)
.addMBB(TargetMBB)
.addImm(0);
return true;
}
Register Reg = MI.getOperand(0).getReg();
Module &M = *MBB.getParent()->getFunction().getParent();
if (M.getStackProtectorGuard() == "sysreg") {
const AArch64SysReg::SysReg *SrcReg =
AArch64SysReg::lookupSysRegByName(M.getStackProtectorGuardReg());
if (!SrcReg)
report_fatal_error("Unknown SysReg for Stack Protector Guard Register");
// mrs xN, sysreg
BuildMI(MBB, MI, DL, get(AArch64::MRS))
.addDef(Reg, RegState::Renamable)
.addImm(SrcReg->Encoding);
int Offset = M.getStackProtectorGuardOffset();
if (Offset >= 0 && Offset <= 32760 && Offset % 8 == 0) {
// ldr xN, [xN, #offset]
BuildMI(MBB, MI, DL, get(AArch64::LDRXui))
.addDef(Reg)
.addUse(Reg, RegState::Kill)
.addImm(Offset / 8);
} else if (Offset >= -256 && Offset <= 255) {
// ldur xN, [xN, #offset]
BuildMI(MBB, MI, DL, get(AArch64::LDURXi))
.addDef(Reg)
.addUse(Reg, RegState::Kill)
.addImm(Offset);
} else if (Offset >= -4095 && Offset <= 4095) {
if (Offset > 0) {
// add xN, xN, #offset
BuildMI(MBB, MI, DL, get(AArch64::ADDXri))
.addDef(Reg)
.addUse(Reg, RegState::Kill)
.addImm(Offset)
.addImm(0);
} else {
// sub xN, xN, #offset
BuildMI(MBB, MI, DL, get(AArch64::SUBXri))
.addDef(Reg)
.addUse(Reg, RegState::Kill)
.addImm(-Offset)
.addImm(0);
}
// ldr xN, [xN]
BuildMI(MBB, MI, DL, get(AArch64::LDRXui))
.addDef(Reg)
.addUse(Reg, RegState::Kill)
.addImm(0);
} else {
// Cases that are larger than +/- 4095 and not a multiple of 8, or larger
// than 23760.
// It might be nice to use AArch64::MOVi32imm here, which would get
// expanded in PreSched2 after PostRA, but our lone scratch Reg already
// contains the MRS result. findScratchNonCalleeSaveRegister() in
// AArch64FrameLowering might help us find such a scratch register
// though. If we failed to find a scratch register, we could emit a
// stream of add instructions to build up the immediate. Or, we could try
// to insert a AArch64::MOVi32imm before register allocation so that we
// didn't need to scavenge for a scratch register.
report_fatal_error("Unable to encode Stack Protector Guard Offset");
}
MBB.erase(MI);
return true;
}
const GlobalValue *GV =
cast<GlobalValue>((*MI.memoperands_begin())->getValue());
const TargetMachine &TM = MBB.getParent()->getTarget();
unsigned OpFlags = Subtarget.ClassifyGlobalReference(GV, TM);
const unsigned char MO_NC = AArch64II::MO_NC;
if ((OpFlags & AArch64II::MO_GOT) != 0) {
BuildMI(MBB, MI, DL, get(AArch64::LOADgot), Reg)
.addGlobalAddress(GV, 0, OpFlags);
if (Subtarget.isTargetILP32()) {
unsigned Reg32 = TRI->getSubReg(Reg, AArch64::sub_32);
BuildMI(MBB, MI, DL, get(AArch64::LDRWui))
.addDef(Reg32, RegState::Dead)
.addUse(Reg, RegState::Kill)
.addImm(0)
.addMemOperand(*MI.memoperands_begin())
.addDef(Reg, RegState::Implicit);
} else {
BuildMI(MBB, MI, DL, get(AArch64::LDRXui), Reg)
.addReg(Reg, RegState::Kill)
.addImm(0)
.addMemOperand(*MI.memoperands_begin());
}
} else if (TM.getCodeModel() == CodeModel::Large) {
assert(!Subtarget.isTargetILP32() && "how can large exist in ILP32?");
BuildMI(MBB, MI, DL, get(AArch64::MOVZXi), Reg)
.addGlobalAddress(GV, 0, AArch64II::MO_G0 | MO_NC)
.addImm(0);
BuildMI(MBB, MI, DL, get(AArch64::MOVKXi), Reg)
.addReg(Reg, RegState::Kill)
.addGlobalAddress(GV, 0, AArch64II::MO_G1 | MO_NC)
.addImm(16);
BuildMI(MBB, MI, DL, get(AArch64::MOVKXi), Reg)
.addReg(Reg, RegState::Kill)
.addGlobalAddress(GV, 0, AArch64II::MO_G2 | MO_NC)
.addImm(32);
BuildMI(MBB, MI, DL, get(AArch64::MOVKXi), Reg)
.addReg(Reg, RegState::Kill)
.addGlobalAddress(GV, 0, AArch64II::MO_G3)
.addImm(48);
BuildMI(MBB, MI, DL, get(AArch64::LDRXui), Reg)
.addReg(Reg, RegState::Kill)
.addImm(0)
.addMemOperand(*MI.memoperands_begin());
} else if (TM.getCodeModel() == CodeModel::Tiny) {
BuildMI(MBB, MI, DL, get(AArch64::ADR), Reg)
.addGlobalAddress(GV, 0, OpFlags);
} else {
BuildMI(MBB, MI, DL, get(AArch64::ADRP), Reg)
.addGlobalAddress(GV, 0, OpFlags | AArch64II::MO_PAGE);
unsigned char LoFlags = OpFlags | AArch64II::MO_PAGEOFF | MO_NC;
if (Subtarget.isTargetILP32()) {
unsigned Reg32 = TRI->getSubReg(Reg, AArch64::sub_32);
BuildMI(MBB, MI, DL, get(AArch64::LDRWui))
.addDef(Reg32, RegState::Dead)
.addUse(Reg, RegState::Kill)
.addGlobalAddress(GV, 0, LoFlags)
.addMemOperand(*MI.memoperands_begin())
.addDef(Reg, RegState::Implicit);
} else {
BuildMI(MBB, MI, DL, get(AArch64::LDRXui), Reg)
.addReg(Reg, RegState::Kill)
.addGlobalAddress(GV, 0, LoFlags)
.addMemOperand(*MI.memoperands_begin());
}
}
MBB.erase(MI);
return true;
}
// Return true if this instruction simply sets its single destination register
// to zero. This is equivalent to a register rename of the zero-register.
bool AArch64InstrInfo::isGPRZero(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
break;
case AArch64::MOVZWi:
case AArch64::MOVZXi: // movz Rd, #0 (LSL #0)
if (MI.getOperand(1).isImm() && MI.getOperand(1).getImm() == 0) {
assert(MI.getDesc().getNumOperands() == 3 &&
MI.getOperand(2).getImm() == 0 && "invalid MOVZi operands");
return true;
}
break;
case AArch64::ANDWri: // and Rd, Rzr, #imm
return MI.getOperand(1).getReg() == AArch64::WZR;
case AArch64::ANDXri:
return MI.getOperand(1).getReg() == AArch64::XZR;
case TargetOpcode::COPY:
return MI.getOperand(1).getReg() == AArch64::WZR;
}
return false;
}
// Return true if this instruction simply renames a general register without
// modifying bits.
bool AArch64InstrInfo::isGPRCopy(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
break;
case TargetOpcode::COPY: {
// GPR32 copies will by lowered to ORRXrs
Register DstReg = MI.getOperand(0).getReg();
return (AArch64::GPR32RegClass.contains(DstReg) ||
AArch64::GPR64RegClass.contains(DstReg));
}
case AArch64::ORRXrs: // orr Xd, Xzr, Xm (LSL #0)
if (MI.getOperand(1).getReg() == AArch64::XZR) {
assert(MI.getDesc().getNumOperands() == 4 &&
MI.getOperand(3).getImm() == 0 && "invalid ORRrs operands");
return true;
}
break;
case AArch64::ADDXri: // add Xd, Xn, #0 (LSL #0)
if (MI.getOperand(2).getImm() == 0) {
assert(MI.getDesc().getNumOperands() == 4 &&
MI.getOperand(3).getImm() == 0 && "invalid ADDXri operands");
return true;
}
break;
}
return false;
}
// Return true if this instruction simply renames a general register without
// modifying bits.
bool AArch64InstrInfo::isFPRCopy(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
break;
case TargetOpcode::COPY: {
Register DstReg = MI.getOperand(0).getReg();
return AArch64::FPR128RegClass.contains(DstReg);
}
case AArch64::ORRv16i8:
if (MI.getOperand(1).getReg() == MI.getOperand(2).getReg()) {
assert(MI.getDesc().getNumOperands() == 3 && MI.getOperand(0).isReg() &&
"invalid ORRv16i8 operands");
return true;
}
break;
}
return false;
}
Register AArch64InstrInfo::isLoadFromStackSlot(const MachineInstr &MI,
int &FrameIndex) const {
switch (MI.getOpcode()) {
default:
break;
case AArch64::LDRWui:
case AArch64::LDRXui:
case AArch64::LDRBui:
case AArch64::LDRHui:
case AArch64::LDRSui:
case AArch64::LDRDui:
case AArch64::LDRQui:
case AArch64::LDR_PXI:
if (MI.getOperand(0).getSubReg() == 0 && MI.getOperand(1).isFI() &&
MI.getOperand(2).isImm() && MI.getOperand(2).getImm() == 0) {
FrameIndex = MI.getOperand(1).getIndex();
return MI.getOperand(0).getReg();
}
break;
}
return 0;
}
Register AArch64InstrInfo::isStoreToStackSlot(const MachineInstr &MI,
int &FrameIndex) const {
switch (MI.getOpcode()) {
default:
break;
case AArch64::STRWui:
case AArch64::STRXui:
case AArch64::STRBui:
case AArch64::STRHui:
case AArch64::STRSui:
case AArch64::STRDui:
case AArch64::STRQui:
case AArch64::STR_PXI:
if (MI.getOperand(0).getSubReg() == 0 && MI.getOperand(1).isFI() &&
MI.getOperand(2).isImm() && MI.getOperand(2).getImm() == 0) {
FrameIndex = MI.getOperand(1).getIndex();
return MI.getOperand(0).getReg();
}
break;
}
return 0;
}
/// Check all MachineMemOperands for a hint to suppress pairing.
bool AArch64InstrInfo::isLdStPairSuppressed(const MachineInstr &MI) {
return llvm::any_of(MI.memoperands(), [](MachineMemOperand *MMO) {
return MMO->getFlags() & MOSuppressPair;
});
}
/// Set a flag on the first MachineMemOperand to suppress pairing.
void AArch64InstrInfo::suppressLdStPair(MachineInstr &MI) {
if (MI.memoperands_empty())
return;
(*MI.memoperands_begin())->setFlags(MOSuppressPair);
}
/// Check all MachineMemOperands for a hint that the load/store is strided.
bool AArch64InstrInfo::isStridedAccess(const MachineInstr &MI) {
return llvm::any_of(MI.memoperands(), [](MachineMemOperand *MMO) {
return MMO->getFlags() & MOStridedAccess;
});
}
bool AArch64InstrInfo::hasUnscaledLdStOffset(unsigned Opc) {
switch (Opc) {
default:
return false;
case AArch64::STURSi:
case AArch64::STRSpre:
case AArch64::STURDi:
case AArch64::STRDpre:
case AArch64::STURQi:
case AArch64::STRQpre:
case AArch64::STURBBi:
case AArch64::STURHHi:
case AArch64::STURWi:
case AArch64::STRWpre:
case AArch64::STURXi:
case AArch64::STRXpre:
case AArch64::LDURSi:
case AArch64::LDRSpre:
case AArch64::LDURDi:
case AArch64::LDRDpre:
case AArch64::LDURQi:
case AArch64::LDRQpre:
case AArch64::LDURWi:
case AArch64::LDRWpre:
case AArch64::LDURXi:
case AArch64::LDRXpre:
case AArch64::LDRSWpre:
case AArch64::LDURSWi:
case AArch64::LDURHHi:
case AArch64::LDURBBi:
case AArch64::LDURSBWi:
case AArch64::LDURSHWi:
return true;
}
}
std::optional<unsigned> AArch64InstrInfo::getUnscaledLdSt(unsigned Opc) {
switch (Opc) {
default: return {};
case AArch64::PRFMui: return AArch64::PRFUMi;
case AArch64::LDRXui: return AArch64::LDURXi;
case AArch64::LDRWui: return AArch64::LDURWi;
case AArch64::LDRBui: return AArch64::LDURBi;
case AArch64::LDRHui: return AArch64::LDURHi;
case AArch64::LDRSui: return AArch64::LDURSi;
case AArch64::LDRDui: return AArch64::LDURDi;
case AArch64::LDRQui: return AArch64::LDURQi;
case AArch64::LDRBBui: return AArch64::LDURBBi;
case AArch64::LDRHHui: return AArch64::LDURHHi;
case AArch64::LDRSBXui: return AArch64::LDURSBXi;
case AArch64::LDRSBWui: return AArch64::LDURSBWi;
case AArch64::LDRSHXui: return AArch64::LDURSHXi;
case AArch64::LDRSHWui: return AArch64::LDURSHWi;
case AArch64::LDRSWui: return AArch64::LDURSWi;
case AArch64::STRXui: return AArch64::STURXi;
case AArch64::STRWui: return AArch64::STURWi;
case AArch64::STRBui: return AArch64::STURBi;
case AArch64::STRHui: return AArch64::STURHi;
case AArch64::STRSui: return AArch64::STURSi;
case AArch64::STRDui: return AArch64::STURDi;
case AArch64::STRQui: return AArch64::STURQi;
case AArch64::STRBBui: return AArch64::STURBBi;
case AArch64::STRHHui: return AArch64::STURHHi;
}
}
unsigned AArch64InstrInfo::getLoadStoreImmIdx(unsigned Opc) {
switch (Opc) {
default:
return 2;
case AArch64::LDPXi:
case AArch64::LDPDi:
case AArch64::STPXi:
case AArch64::STPDi:
case AArch64::LDNPXi:
case AArch64::LDNPDi:
case AArch64::STNPXi:
case AArch64::STNPDi:
case AArch64::LDPQi:
case AArch64::STPQi:
case AArch64::LDNPQi:
case AArch64::STNPQi:
case AArch64::LDPWi:
case AArch64::LDPSi:
case AArch64::STPWi:
case AArch64::STPSi:
case AArch64::LDNPWi:
case AArch64::LDNPSi:
case AArch64::STNPWi:
case AArch64::STNPSi:
case AArch64::LDG:
case AArch64::STGPi:
case AArch64::LD1B_IMM:
case AArch64::LD1B_H_IMM:
case AArch64::LD1B_S_IMM:
case AArch64::LD1B_D_IMM:
case AArch64::LD1SB_H_IMM:
case AArch64::LD1SB_S_IMM:
case AArch64::LD1SB_D_IMM:
case AArch64::LD1H_IMM:
case AArch64::LD1H_S_IMM:
case AArch64::LD1H_D_IMM:
case AArch64::LD1SH_S_IMM:
case AArch64::LD1SH_D_IMM:
case AArch64::LD1W_IMM:
case AArch64::LD1W_D_IMM:
case AArch64::LD1SW_D_IMM:
case AArch64::LD1D_IMM:
case AArch64::LD2B_IMM:
case AArch64::LD2H_IMM:
case AArch64::LD2W_IMM:
case AArch64::LD2D_IMM:
case AArch64::LD3B_IMM:
case AArch64::LD3H_IMM:
case AArch64::LD3W_IMM:
case AArch64::LD3D_IMM:
case AArch64::LD4B_IMM:
case AArch64::LD4H_IMM:
case AArch64::LD4W_IMM:
case AArch64::LD4D_IMM:
case AArch64::ST1B_IMM:
case AArch64::ST1B_H_IMM:
case AArch64::ST1B_S_IMM:
case AArch64::ST1B_D_IMM:
case AArch64::ST1H_IMM:
case AArch64::ST1H_S_IMM:
case AArch64::ST1H_D_IMM:
case AArch64::ST1W_IMM:
case AArch64::ST1W_D_IMM:
case AArch64::ST1D_IMM:
case AArch64::ST2B_IMM:
case AArch64::ST2H_IMM:
case AArch64::ST2W_IMM:
case AArch64::ST2D_IMM:
case AArch64::ST3B_IMM:
case AArch64::ST3H_IMM:
case AArch64::ST3W_IMM:
case AArch64::ST3D_IMM:
case AArch64::ST4B_IMM:
case AArch64::ST4H_IMM:
case AArch64::ST4W_IMM:
case AArch64::ST4D_IMM:
case AArch64::LD1RB_IMM:
case AArch64::LD1RB_H_IMM:
case AArch64::LD1RB_S_IMM:
case AArch64::LD1RB_D_IMM:
case AArch64::LD1RSB_H_IMM:
case AArch64::LD1RSB_S_IMM:
case AArch64::LD1RSB_D_IMM:
case AArch64::LD1RH_IMM:
case AArch64::LD1RH_S_IMM:
case AArch64::LD1RH_D_IMM:
case AArch64::LD1RSH_S_IMM:
case AArch64::LD1RSH_D_IMM:
case AArch64::LD1RW_IMM:
case AArch64::LD1RW_D_IMM:
case AArch64::LD1RSW_IMM:
case AArch64::LD1RD_IMM:
case AArch64::LDNT1B_ZRI:
case AArch64::LDNT1H_ZRI:
case AArch64::LDNT1W_ZRI:
case AArch64::LDNT1D_ZRI:
case AArch64::STNT1B_ZRI:
case AArch64::STNT1H_ZRI:
case AArch64::STNT1W_ZRI:
case AArch64::STNT1D_ZRI:
case AArch64::LDNF1B_IMM:
case AArch64::LDNF1B_H_IMM:
case AArch64::LDNF1B_S_IMM:
case AArch64::LDNF1B_D_IMM:
case AArch64::LDNF1SB_H_IMM:
case AArch64::LDNF1SB_S_IMM:
case AArch64::LDNF1SB_D_IMM:
case AArch64::LDNF1H_IMM:
case AArch64::LDNF1H_S_IMM:
case AArch64::LDNF1H_D_IMM:
case AArch64::LDNF1SH_S_IMM:
case AArch64::LDNF1SH_D_IMM:
case AArch64::LDNF1W_IMM:
case AArch64::LDNF1W_D_IMM:
case AArch64::LDNF1SW_D_IMM:
case AArch64::LDNF1D_IMM:
return 3;
case AArch64::ADDG:
case AArch64::STGi:
case AArch64::LDR_PXI:
case AArch64::STR_PXI:
return 2;
}
}
bool AArch64InstrInfo::isPairableLdStInst(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
return false;
// Scaled instructions.
case AArch64::STRSui:
case AArch64::STRDui:
case AArch64::STRQui:
case AArch64::STRXui:
case AArch64::STRWui:
case AArch64::LDRSui:
case AArch64::LDRDui:
case AArch64::LDRQui:
case AArch64::LDRXui:
case AArch64::LDRWui:
case AArch64::LDRSWui:
// Unscaled instructions.
case AArch64::STURSi:
case AArch64::STRSpre:
case AArch64::STURDi:
case AArch64::STRDpre:
case AArch64::STURQi:
case AArch64::STRQpre:
case AArch64::STURWi:
case AArch64::STRWpre:
case AArch64::STURXi:
case AArch64::STRXpre:
case AArch64::LDURSi:
case AArch64::LDRSpre:
case AArch64::LDURDi:
case AArch64::LDRDpre:
case AArch64::LDURQi:
case AArch64::LDRQpre:
case AArch64::LDURWi:
case AArch64::LDRWpre:
case AArch64::LDURXi:
case AArch64::LDRXpre:
case AArch64::LDURSWi:
case AArch64::LDRSWpre:
return true;
}
}
bool AArch64InstrInfo::isTailCallReturnInst(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
assert((!MI.isCall() || !MI.isReturn()) &&
"Unexpected instruction - was a new tail call opcode introduced?");
return false;
case AArch64::TCRETURNdi:
case AArch64::TCRETURNri:
case AArch64::TCRETURNrix16x17:
case AArch64::TCRETURNrix17:
case AArch64::TCRETURNrinotx16:
case AArch64::TCRETURNriALL:
return true;
}
}
unsigned AArch64InstrInfo::convertToFlagSettingOpc(unsigned Opc) {
switch (Opc) {
default:
llvm_unreachable("Opcode has no flag setting equivalent!");
// 32-bit cases:
case AArch64::ADDWri:
return AArch64::ADDSWri;
case AArch64::ADDWrr:
return AArch64::ADDSWrr;
case AArch64::ADDWrs:
return AArch64::ADDSWrs;
case AArch64::ADDWrx:
return AArch64::ADDSWrx;
case AArch64::ANDWri:
return AArch64::ANDSWri;
case AArch64::ANDWrr:
return AArch64::ANDSWrr;
case AArch64::ANDWrs:
return AArch64::ANDSWrs;
case AArch64::BICWrr:
return AArch64::BICSWrr;
case AArch64::BICWrs:
return AArch64::BICSWrs;
case AArch64::SUBWri:
return AArch64::SUBSWri;
case AArch64::SUBWrr:
return AArch64::SUBSWrr;
case AArch64::SUBWrs:
return AArch64::SUBSWrs;
case AArch64::SUBWrx:
return AArch64::SUBSWrx;
// 64-bit cases:
case AArch64::ADDXri:
return AArch64::ADDSXri;
case AArch64::ADDXrr:
return AArch64::ADDSXrr;
case AArch64::ADDXrs:
return AArch64::ADDSXrs;
case AArch64::ADDXrx:
return AArch64::ADDSXrx;
case AArch64::ANDXri:
return AArch64::ANDSXri;
case AArch64::ANDXrr:
return AArch64::ANDSXrr;
case AArch64::ANDXrs:
return AArch64::ANDSXrs;
case AArch64::BICXrr:
return AArch64::BICSXrr;
case AArch64::BICXrs:
return AArch64::BICSXrs;
case AArch64::SUBXri:
return AArch64::SUBSXri;
case AArch64::SUBXrr:
return AArch64::SUBSXrr;
case AArch64::SUBXrs:
return AArch64::SUBSXrs;
case AArch64::SUBXrx:
return AArch64::SUBSXrx;
// SVE instructions:
case AArch64::AND_PPzPP:
return AArch64::ANDS_PPzPP;
case AArch64::BIC_PPzPP:
return AArch64::BICS_PPzPP;
case AArch64::EOR_PPzPP:
return AArch64::EORS_PPzPP;
case AArch64::NAND_PPzPP:
return AArch64::NANDS_PPzPP;
case AArch64::NOR_PPzPP:
return AArch64::NORS_PPzPP;
case AArch64::ORN_PPzPP:
return AArch64::ORNS_PPzPP;
case AArch64::ORR_PPzPP:
return AArch64::ORRS_PPzPP;
case AArch64::BRKA_PPzP:
return AArch64::BRKAS_PPzP;
case AArch64::BRKPA_PPzPP:
return AArch64::BRKPAS_PPzPP;
case AArch64::BRKB_PPzP:
return AArch64::BRKBS_PPzP;
case AArch64::BRKPB_PPzPP:
return AArch64::BRKPBS_PPzPP;
case AArch64::BRKN_PPzP:
return AArch64::BRKNS_PPzP;
case AArch64::RDFFR_PPz:
return AArch64::RDFFRS_PPz;
case AArch64::PTRUE_B:
return AArch64::PTRUES_B;
}
}
// Is this a candidate for ld/st merging or pairing? For example, we don't
// touch volatiles or load/stores that have a hint to avoid pair formation.
bool AArch64InstrInfo::isCandidateToMergeOrPair(const MachineInstr &MI) const {
bool IsPreLdSt = isPreLdSt(MI);
// If this is a volatile load/store, don't mess with it.
if (MI.hasOrderedMemoryRef())
return false;
// Make sure this is a reg/fi+imm (as opposed to an address reloc).
// For Pre-inc LD/ST, the operand is shifted by one.
assert((MI.getOperand(IsPreLdSt ? 2 : 1).isReg() ||
MI.getOperand(IsPreLdSt ? 2 : 1).isFI()) &&
"Expected a reg or frame index operand.");
// For Pre-indexed addressing quadword instructions, the third operand is the
// immediate value.
bool IsImmPreLdSt = IsPreLdSt && MI.getOperand(3).isImm();
if (!MI.getOperand(2).isImm() && !IsImmPreLdSt)
return false;
// Can't merge/pair if the instruction modifies the base register.
// e.g., ldr x0, [x0]
// This case will never occur with an FI base.
// However, if the instruction is an LDR<S,D,Q,W,X,SW>pre or
// STR<S,D,Q,W,X>pre, it can be merged.
// For example:
// ldr q0, [x11, #32]!
// ldr q1, [x11, #16]
// to
// ldp q0, q1, [x11, #32]!
if (MI.getOperand(1).isReg() && !IsPreLdSt) {
Register BaseReg = MI.getOperand(1).getReg();
const TargetRegisterInfo *TRI = &getRegisterInfo();
if (MI.modifiesRegister(BaseReg, TRI))
return false;
}
// Check if this load/store has a hint to avoid pair formation.
// MachineMemOperands hints are set by the AArch64StorePairSuppress pass.
if (isLdStPairSuppressed(MI))
return false;
// Do not pair any callee-save store/reload instructions in the
// prologue/epilogue if the CFI information encoded the operations as separate
// instructions, as that will cause the size of the actual prologue to mismatch
// with the prologue size recorded in the Windows CFI.
const MCAsmInfo *MAI = MI.getMF()->getTarget().getMCAsmInfo();
bool NeedsWinCFI = MAI->usesWindowsCFI() &&
MI.getMF()->getFunction().needsUnwindTableEntry();
if (NeedsWinCFI && (MI.getFlag(MachineInstr::FrameSetup) ||
MI.getFlag(MachineInstr::FrameDestroy)))
return false;
// On some CPUs quad load/store pairs are slower than two single load/stores.
if (Subtarget.isPaired128Slow()) {
switch (MI.getOpcode()) {
default:
break;
case AArch64::LDURQi:
case AArch64::STURQi:
case AArch64::LDRQui:
case AArch64::STRQui:
return false;
}
}
return true;
}
bool AArch64InstrInfo::getMemOperandsWithOffsetWidth(
const MachineInstr &LdSt, SmallVectorImpl<const MachineOperand *> &BaseOps,
int64_t &Offset, bool &OffsetIsScalable, LocationSize &Width,
const TargetRegisterInfo *TRI) const {
if (!LdSt.mayLoadOrStore())
return false;
const MachineOperand *BaseOp;
TypeSize WidthN(0, false);
if (!getMemOperandWithOffsetWidth(LdSt, BaseOp, Offset, OffsetIsScalable,
WidthN, TRI))
return false;
// The maximum vscale is 16 under AArch64, return the maximal extent for the
// vector.
Width = LocationSize::precise(WidthN);
BaseOps.push_back(BaseOp);
return true;
}
std::optional<ExtAddrMode>
AArch64InstrInfo::getAddrModeFromMemoryOp(const MachineInstr &MemI,
const TargetRegisterInfo *TRI) const {
const MachineOperand *Base; // Filled with the base operand of MI.
int64_t Offset; // Filled with the offset of MI.
bool OffsetIsScalable;
if (!getMemOperandWithOffset(MemI, Base, Offset, OffsetIsScalable, TRI))
return std::nullopt;
if (!Base->isReg())
return std::nullopt;
ExtAddrMode AM;
AM.BaseReg = Base->getReg();
AM.Displacement = Offset;
AM.ScaledReg = 0;
AM.Scale = 0;
return AM;
}
bool AArch64InstrInfo::canFoldIntoAddrMode(const MachineInstr &MemI,
Register Reg,
const MachineInstr &AddrI,
ExtAddrMode &AM) const {
// Filter out instructions into which we cannot fold.
unsigned NumBytes;
int64_t OffsetScale = 1;
switch (MemI.getOpcode()) {
default:
return false;
case AArch64::LDURQi:
case AArch64::STURQi:
NumBytes = 16;
break;
case AArch64::LDURDi:
case AArch64::STURDi:
case AArch64::LDURXi:
case AArch64::STURXi:
NumBytes = 8;
break;
case AArch64::LDURWi:
case AArch64::LDURSWi:
case AArch64::STURWi:
NumBytes = 4;
break;
case AArch64::LDURHi:
case AArch64::STURHi:
case AArch64::LDURHHi:
case AArch64::STURHHi:
case AArch64::LDURSHXi:
case AArch64::LDURSHWi:
NumBytes = 2;
break;
case AArch64::LDRBroX:
case AArch64::LDRBBroX:
case AArch64::LDRSBXroX:
case AArch64::LDRSBWroX:
case AArch64::STRBroX:
case AArch64::STRBBroX:
case AArch64::LDURBi:
case AArch64::LDURBBi:
case AArch64::LDURSBXi:
case AArch64::LDURSBWi:
case AArch64::STURBi:
case AArch64::STURBBi:
case AArch64::LDRBui:
case AArch64::LDRBBui:
case AArch64::LDRSBXui:
case AArch64::LDRSBWui:
case AArch64::STRBui:
case AArch64::STRBBui:
NumBytes = 1;
break;
case AArch64::LDRQroX:
case AArch64::STRQroX:
case AArch64::LDRQui:
case AArch64::STRQui:
NumBytes = 16;
OffsetScale = 16;
break;
case AArch64::LDRDroX:
case AArch64::STRDroX:
case AArch64::LDRXroX:
case AArch64::STRXroX:
case AArch64::LDRDui:
case AArch64::STRDui:
case AArch64::LDRXui:
case AArch64::STRXui:
NumBytes = 8;
OffsetScale = 8;
break;
case AArch64::LDRWroX:
case AArch64::LDRSWroX:
case AArch64::STRWroX:
case AArch64::LDRWui:
case AArch64::LDRSWui:
case AArch64::STRWui:
NumBytes = 4;
OffsetScale = 4;
break;
case AArch64::LDRHroX:
case AArch64::STRHroX:
case AArch64::LDRHHroX:
case AArch64::STRHHroX:
case AArch64::LDRSHXroX:
case AArch64::LDRSHWroX:
case AArch64::LDRHui:
case AArch64::STRHui:
case AArch64::LDRHHui:
case AArch64::STRHHui:
case AArch64::LDRSHXui:
case AArch64::LDRSHWui:
NumBytes = 2;
OffsetScale = 2;
break;
}
// Check the fold operand is not the loaded/stored value.
const MachineOperand &BaseRegOp = MemI.getOperand(0);
if (BaseRegOp.isReg() && BaseRegOp.getReg() == Reg)
return false;
// Handle memory instructions with a [Reg, Reg] addressing mode.
if (MemI.getOperand(2).isReg()) {
// Bail if the addressing mode already includes extension of the offset
// register.
if (MemI.getOperand(3).getImm())
return false;
// Check if we actually have a scaled offset.
if (MemI.getOperand(4).getImm() == 0)
OffsetScale = 1;
// If the address instructions is folded into the base register, then the
// addressing mode must not have a scale. Then we can swap the base and the
// scaled registers.
if (MemI.getOperand(1).getReg() == Reg && OffsetScale != 1)
return false;
switch (AddrI.getOpcode()) {
default:
return false;
case AArch64::SBFMXri:
// sxtw Xa, Wm
// ldr Xd, [Xn, Xa, lsl #N]
// ->
// ldr Xd, [Xn, Wm, sxtw #N]
if (AddrI.getOperand(2).getImm() != 0 ||
AddrI.getOperand(3).getImm() != 31)
return false;
AM.BaseReg = MemI.getOperand(1).getReg();
if (AM.BaseReg == Reg)
AM.BaseReg = MemI.getOperand(2).getReg();
AM.ScaledReg = AddrI.getOperand(1).getReg();
AM.Scale = OffsetScale;
AM.Displacement = 0;
AM.Form = ExtAddrMode::Formula::SExtScaledReg;
return true;
case TargetOpcode::SUBREG_TO_REG: {
// mov Wa, Wm
// ldr Xd, [Xn, Xa, lsl #N]
// ->
// ldr Xd, [Xn, Wm, uxtw #N]
// Zero-extension looks like an ORRWrs followed by a SUBREG_TO_REG.
if (AddrI.getOperand(1).getImm() != 0 ||
AddrI.getOperand(3).getImm() != AArch64::sub_32)
return false;
const MachineRegisterInfo &MRI = AddrI.getMF()->getRegInfo();
Register OffsetReg = AddrI.getOperand(2).getReg();
if (!OffsetReg.isVirtual() || !MRI.hasOneNonDBGUse(OffsetReg))
return false;
const MachineInstr &DefMI = *MRI.getVRegDef(OffsetReg);
if (DefMI.getOpcode() != AArch64::ORRWrs ||
DefMI.getOperand(1).getReg() != AArch64::WZR ||
DefMI.getOperand(3).getImm() != 0)
return false;
AM.BaseReg = MemI.getOperand(1).getReg();
if (AM.BaseReg == Reg)
AM.BaseReg = MemI.getOperand(2).getReg();
AM.ScaledReg = DefMI.getOperand(2).getReg();
AM.Scale = OffsetScale;
AM.Displacement = 0;
AM.Form = ExtAddrMode::Formula::ZExtScaledReg;
return true;
}
}
}
// Handle memory instructions with a [Reg, #Imm] addressing mode.
// Check we are not breaking a potential conversion to an LDP.
auto validateOffsetForLDP = [](unsigned NumBytes, int64_t OldOffset,
int64_t NewOffset) -> bool {
int64_t MinOffset, MaxOffset;
switch (NumBytes) {
default:
return true;
case 4:
MinOffset = -256;
MaxOffset = 252;
break;
case 8:
MinOffset = -512;
MaxOffset = 504;
break;
case 16:
MinOffset = -1024;
MaxOffset = 1008;
break;
}
return OldOffset < MinOffset || OldOffset > MaxOffset ||
(NewOffset >= MinOffset && NewOffset <= MaxOffset);
};
auto canFoldAddSubImmIntoAddrMode = [&](int64_t Disp) -> bool {
int64_t OldOffset = MemI.getOperand(2).getImm() * OffsetScale;
int64_t NewOffset = OldOffset + Disp;
if (!isLegalAddressingMode(NumBytes, NewOffset, /* Scale */ 0))
return false;
// If the old offset would fit into an LDP, but the new offset wouldn't,
// bail out.
if (!validateOffsetForLDP(NumBytes, OldOffset, NewOffset))
return false;
AM.BaseReg = AddrI.getOperand(1).getReg();
AM.ScaledReg = 0;
AM.Scale = 0;
AM.Displacement = NewOffset;
AM.Form = ExtAddrMode::Formula::Basic;
return true;
};
auto canFoldAddRegIntoAddrMode =
[&](int64_t Scale,
ExtAddrMode::Formula Form = ExtAddrMode::Formula::Basic) -> bool {
if (MemI.getOperand(2).getImm() != 0)
return false;
if (!isLegalAddressingMode(NumBytes, /* Offset */ 0, Scale))
return false;
AM.BaseReg = AddrI.getOperand(1).getReg();
AM.ScaledReg = AddrI.getOperand(2).getReg();
AM.Scale = Scale;
AM.Displacement = 0;
AM.Form = Form;
return true;
};
auto avoidSlowSTRQ = [&](const MachineInstr &MemI) {
unsigned Opcode = MemI.getOpcode();
return (Opcode == AArch64::STURQi || Opcode == AArch64::STRQui) &&
Subtarget.isSTRQroSlow();
};
int64_t Disp = 0;
const bool OptSize = MemI.getMF()->getFunction().hasOptSize();
switch (AddrI.getOpcode()) {
default:
return false;
case AArch64::ADDXri:
// add Xa, Xn, #N
// ldr Xd, [Xa, #M]
// ->
// ldr Xd, [Xn, #N'+M]
Disp = AddrI.getOperand(2).getImm() << AddrI.getOperand(3).getImm();
return canFoldAddSubImmIntoAddrMode(Disp);
case AArch64::SUBXri:
// sub Xa, Xn, #N
// ldr Xd, [Xa, #M]
// ->
// ldr Xd, [Xn, #N'+M]
Disp = AddrI.getOperand(2).getImm() << AddrI.getOperand(3).getImm();
return canFoldAddSubImmIntoAddrMode(-Disp);
case AArch64::ADDXrs: {
// add Xa, Xn, Xm, lsl #N
// ldr Xd, [Xa]
// ->
// ldr Xd, [Xn, Xm, lsl #N]
// Don't fold the add if the result would be slower, unless optimising for
// size.
unsigned Shift = static_cast<unsigned>(AddrI.getOperand(3).getImm());
if (AArch64_AM::getShiftType(Shift) != AArch64_AM::ShiftExtendType::LSL)
return false;
Shift = AArch64_AM::getShiftValue(Shift);
if (!OptSize) {
if (Shift != 2 && Shift != 3 && Subtarget.hasAddrLSLSlow14())
return false;
if (avoidSlowSTRQ(MemI))
return false;
}
return canFoldAddRegIntoAddrMode(1ULL << Shift);
}
case AArch64::ADDXrr:
// add Xa, Xn, Xm
// ldr Xd, [Xa]
// ->
// ldr Xd, [Xn, Xm, lsl #0]
// Don't fold the add if the result would be slower, unless optimising for
// size.
if (!OptSize && avoidSlowSTRQ(MemI))
return false;
return canFoldAddRegIntoAddrMode(1);
case AArch64::ADDXrx:
// add Xa, Xn, Wm, {s,u}xtw #N
// ldr Xd, [Xa]
// ->
// ldr Xd, [Xn, Wm, {s,u}xtw #N]
// Don't fold the add if the result would be slower, unless optimising for
// size.
if (!OptSize && avoidSlowSTRQ(MemI))
return false;
// Can fold only sign-/zero-extend of a word.
unsigned Imm = static_cast<unsigned>(AddrI.getOperand(3).getImm());
AArch64_AM::ShiftExtendType Extend = AArch64_AM::getArithExtendType(Imm);
if (Extend != AArch64_AM::UXTW && Extend != AArch64_AM::SXTW)
return false;
return canFoldAddRegIntoAddrMode(
1ULL << AArch64_AM::getArithShiftValue(Imm),
(Extend == AArch64_AM::SXTW) ? ExtAddrMode::Formula::SExtScaledReg
: ExtAddrMode::Formula::ZExtScaledReg);
}
}
// Given an opcode for an instruction with a [Reg, #Imm] addressing mode,
// return the opcode of an instruction performing the same operation, but using
// the [Reg, Reg] addressing mode.
static unsigned regOffsetOpcode(unsigned Opcode) {
switch (Opcode) {
default:
llvm_unreachable("Address folding not implemented for instruction");
case AArch64::LDURQi:
case AArch64::LDRQui:
return AArch64::LDRQroX;
case AArch64::STURQi:
case AArch64::STRQui:
return AArch64::STRQroX;
case AArch64::LDURDi:
case AArch64::LDRDui:
return AArch64::LDRDroX;
case AArch64::STURDi:
case AArch64::STRDui:
return AArch64::STRDroX;
case AArch64::LDURXi:
case AArch64::LDRXui:
return AArch64::LDRXroX;
case AArch64::STURXi:
case AArch64::STRXui:
return AArch64::STRXroX;
case AArch64::LDURWi:
case AArch64::LDRWui:
return AArch64::LDRWroX;
case AArch64::LDURSWi:
case AArch64::LDRSWui:
return AArch64::LDRSWroX;
case AArch64::STURWi:
case AArch64::STRWui:
return AArch64::STRWroX;
case AArch64::LDURHi:
case AArch64::LDRHui:
return AArch64::LDRHroX;
case AArch64::STURHi:
case AArch64::STRHui:
return AArch64::STRHroX;
case AArch64::LDURHHi:
case AArch64::LDRHHui:
return AArch64::LDRHHroX;
case AArch64::STURHHi:
case AArch64::STRHHui:
return AArch64::STRHHroX;
case AArch64::LDURSHXi:
case AArch64::LDRSHXui:
return AArch64::LDRSHXroX;
case AArch64::LDURSHWi:
case AArch64::LDRSHWui:
return AArch64::LDRSHWroX;
case AArch64::LDURBi:
case AArch64::LDRBui:
return AArch64::LDRBroX;
case AArch64::LDURBBi:
case AArch64::LDRBBui:
return AArch64::LDRBBroX;
case AArch64::LDURSBXi:
case AArch64::LDRSBXui:
return AArch64::LDRSBXroX;
case AArch64::LDURSBWi:
case AArch64::LDRSBWui:
return AArch64::LDRSBWroX;
case AArch64::STURBi:
case AArch64::STRBui:
return AArch64::STRBroX;
case AArch64::STURBBi:
case AArch64::STRBBui:
return AArch64::STRBBroX;
}
}
// Given an opcode for an instruction with a [Reg, #Imm] addressing mode, return
// the opcode of an instruction performing the same operation, but using the
// [Reg, #Imm] addressing mode with scaled offset.
unsigned scaledOffsetOpcode(unsigned Opcode, unsigned &Scale) {
switch (Opcode) {
default:
llvm_unreachable("Address folding not implemented for instruction");
case AArch64::LDURQi:
Scale = 16;
return AArch64::LDRQui;
case AArch64::STURQi:
Scale = 16;
return AArch64::STRQui;
case AArch64::LDURDi:
Scale = 8;
return AArch64::LDRDui;
case AArch64::STURDi:
Scale = 8;
return AArch64::STRDui;
case AArch64::LDURXi:
Scale = 8;
return AArch64::LDRXui;
case AArch64::STURXi:
Scale = 8;
return AArch64::STRXui;
case AArch64::LDURWi:
Scale = 4;
return AArch64::LDRWui;
case AArch64::LDURSWi:
Scale = 4;
return AArch64::LDRSWui;
case AArch64::STURWi:
Scale = 4;
return AArch64::STRWui;
case AArch64::LDURHi:
Scale = 2;
return AArch64::LDRHui;
case AArch64::STURHi:
Scale = 2;
return AArch64::STRHui;
case AArch64::LDURHHi:
Scale = 2;
return AArch64::LDRHHui;
case AArch64::STURHHi:
Scale = 2;
return AArch64::STRHHui;
case AArch64::LDURSHXi:
Scale = 2;
return AArch64::LDRSHXui;
case AArch64::LDURSHWi:
Scale = 2;
return AArch64::LDRSHWui;
case AArch64::LDURBi:
Scale = 1;
return AArch64::LDRBui;
case AArch64::LDURBBi:
Scale = 1;
return AArch64::LDRBBui;
case AArch64::LDURSBXi:
Scale = 1;
return AArch64::LDRSBXui;
case AArch64::LDURSBWi:
Scale = 1;
return AArch64::LDRSBWui;
case AArch64::STURBi:
Scale = 1;
return AArch64::STRBui;
case AArch64::STURBBi:
Scale = 1;
return AArch64::STRBBui;
case AArch64::LDRQui:
case AArch64::STRQui:
Scale = 16;
return Opcode;
case AArch64::LDRDui:
case AArch64::STRDui:
case AArch64::LDRXui:
case AArch64::STRXui:
Scale = 8;
return Opcode;
case AArch64::LDRWui:
case AArch64::LDRSWui:
case AArch64::STRWui:
Scale = 4;
return Opcode;
case AArch64::LDRHui:
case AArch64::STRHui:
case AArch64::LDRHHui:
case AArch64::STRHHui:
case AArch64::LDRSHXui:
case AArch64::LDRSHWui:
Scale = 2;
return Opcode;
case AArch64::LDRBui:
case AArch64::LDRBBui:
case AArch64::LDRSBXui:
case AArch64::LDRSBWui:
case AArch64::STRBui:
case AArch64::STRBBui:
Scale = 1;
return Opcode;
}
}
// Given an opcode for an instruction with a [Reg, #Imm] addressing mode, return
// the opcode of an instruction performing the same operation, but using the
// [Reg, #Imm] addressing mode with unscaled offset.
unsigned unscaledOffsetOpcode(unsigned Opcode) {
switch (Opcode) {
default:
llvm_unreachable("Address folding not implemented for instruction");
case AArch64::LDURQi:
case AArch64::STURQi:
case AArch64::LDURDi:
case AArch64::STURDi:
case AArch64::LDURXi:
case AArch64::STURXi:
case AArch64::LDURWi:
case AArch64::LDURSWi:
case AArch64::STURWi:
case AArch64::LDURHi:
case AArch64::STURHi:
case AArch64::LDURHHi:
case AArch64::STURHHi:
case AArch64::LDURSHXi:
case AArch64::LDURSHWi:
case AArch64::LDURBi:
case AArch64::STURBi:
case AArch64::LDURBBi:
case AArch64::STURBBi:
case AArch64::LDURSBWi:
case AArch64::LDURSBXi:
return Opcode;
case AArch64::LDRQui:
return AArch64::LDURQi;
case AArch64::STRQui:
return AArch64::STURQi;
case AArch64::LDRDui:
return AArch64::LDURDi;
case AArch64::STRDui:
return AArch64::STURDi;
case AArch64::LDRXui:
return AArch64::LDURXi;
case AArch64::STRXui:
return AArch64::STURXi;
case AArch64::LDRWui:
return AArch64::LDURWi;
case AArch64::LDRSWui:
return AArch64::LDURSWi;
case AArch64::STRWui:
return AArch64::STURWi;
case AArch64::LDRHui:
return AArch64::LDURHi;
case AArch64::STRHui:
return AArch64::STURHi;
case AArch64::LDRHHui:
return AArch64::LDURHHi;
case AArch64::STRHHui:
return AArch64::STURHHi;
case AArch64::LDRSHXui:
return AArch64::LDURSHXi;
case AArch64::LDRSHWui:
return AArch64::LDURSHWi;
case AArch64::LDRBBui:
return AArch64::LDURBBi;
case AArch64::LDRBui:
return AArch64::LDURBi;
case AArch64::STRBBui:
return AArch64::STURBBi;
case AArch64::STRBui:
return AArch64::STURBi;
case AArch64::LDRSBWui:
return AArch64::LDURSBWi;
case AArch64::LDRSBXui:
return AArch64::LDURSBXi;
}
}
// Given the opcode of a memory load/store instruction, return the opcode of an
// instruction performing the same operation, but using
// the [Reg, Reg, {s,u}xtw #N] addressing mode with sign-/zero-extend of the
// offset register.
static unsigned offsetExtendOpcode(unsigned Opcode) {
switch (Opcode) {
default:
llvm_unreachable("Address folding not implemented for instruction");
case AArch64::LDRQroX:
case AArch64::LDURQi:
case AArch64::LDRQui:
return AArch64::LDRQroW;
case AArch64::STRQroX:
case AArch64::STURQi:
case AArch64::STRQui:
return AArch64::STRQroW;
case AArch64::LDRDroX:
case AArch64::LDURDi:
case AArch64::LDRDui:
return AArch64::LDRDroW;
case AArch64::STRDroX:
case AArch64::STURDi:
case AArch64::STRDui:
return AArch64::STRDroW;
case AArch64::LDRXroX:
case AArch64::LDURXi:
case AArch64::LDRXui:
return AArch64::LDRXroW;
case AArch64::STRXroX:
case AArch64::STURXi:
case AArch64::STRXui:
return AArch64::STRXroW;
case AArch64::LDRWroX:
case AArch64::LDURWi:
case AArch64::LDRWui:
return AArch64::LDRWroW;
case AArch64::LDRSWroX:
case AArch64::LDURSWi:
case AArch64::LDRSWui:
return AArch64::LDRSWroW;
case AArch64::STRWroX:
case AArch64::STURWi:
case AArch64::STRWui:
return AArch64::STRWroW;
case AArch64::LDRHroX:
case AArch64::LDURHi:
case AArch64::LDRHui:
return AArch64::LDRHroW;
case AArch64::STRHroX:
case AArch64::STURHi:
case AArch64::STRHui:
return AArch64::STRHroW;
case AArch64::LDRHHroX:
case AArch64::LDURHHi:
case AArch64::LDRHHui:
return AArch64::LDRHHroW;
case AArch64::STRHHroX:
case AArch64::STURHHi:
case AArch64::STRHHui:
return AArch64::STRHHroW;
case AArch64::LDRSHXroX:
case AArch64::LDURSHXi:
case AArch64::LDRSHXui:
return AArch64::LDRSHXroW;
case AArch64::LDRSHWroX:
case AArch64::LDURSHWi:
case AArch64::LDRSHWui:
return AArch64::LDRSHWroW;
case AArch64::LDRBroX:
case AArch64::LDURBi:
case AArch64::LDRBui:
return AArch64::LDRBroW;
case AArch64::LDRBBroX:
case AArch64::LDURBBi:
case AArch64::LDRBBui:
return AArch64::LDRBBroW;
case AArch64::LDRSBXroX:
case AArch64::LDURSBXi:
case AArch64::LDRSBXui:
return AArch64::LDRSBXroW;
case AArch64::LDRSBWroX:
case AArch64::LDURSBWi:
case AArch64::LDRSBWui:
return AArch64::LDRSBWroW;
case AArch64::STRBroX:
case AArch64::STURBi:
case AArch64::STRBui:
return AArch64::STRBroW;
case AArch64::STRBBroX:
case AArch64::STURBBi:
case AArch64::STRBBui:
return AArch64::STRBBroW;
}
}
MachineInstr *AArch64InstrInfo::emitLdStWithAddr(MachineInstr &MemI,
const ExtAddrMode &AM) const {
const DebugLoc &DL = MemI.getDebugLoc();
MachineBasicBlock &MBB = *MemI.getParent();
MachineRegisterInfo &MRI = MemI.getMF()->getRegInfo();
if (AM.Form == ExtAddrMode::Formula::Basic) {
if (AM.ScaledReg) {
// The new instruction will be in the form `ldr Rt, [Xn, Xm, lsl #imm]`.
unsigned Opcode = regOffsetOpcode(MemI.getOpcode());
MRI.constrainRegClass(AM.BaseReg, &AArch64::GPR64spRegClass);
auto B = BuildMI(MBB, MemI, DL, get(Opcode))
.addReg(MemI.getOperand(0).getReg(),
MemI.mayLoad() ? RegState::Define : 0)
.addReg(AM.BaseReg)
.addReg(AM.ScaledReg)
.addImm(0)
.addImm(AM.Scale > 1)
.setMemRefs(MemI.memoperands())
.setMIFlags(MemI.getFlags());
return B.getInstr();
}
assert(AM.ScaledReg == 0 && AM.Scale == 0 &&
"Addressing mode not supported for folding");
// The new instruction will be in the form `ld[u]r Rt, [Xn, #imm]`.
unsigned Scale = 1;
unsigned Opcode = MemI.getOpcode();
if (isInt<9>(AM.Displacement))
Opcode = unscaledOffsetOpcode(Opcode);
else
Opcode = scaledOffsetOpcode(Opcode, Scale);
auto B = BuildMI(MBB, MemI, DL, get(Opcode))
.addReg(MemI.getOperand(0).getReg(),
MemI.mayLoad() ? RegState::Define : 0)
.addReg(AM.BaseReg)
.addImm(AM.Displacement / Scale)
.setMemRefs(MemI.memoperands())
.setMIFlags(MemI.getFlags());
return B.getInstr();
}
if (AM.Form == ExtAddrMode::Formula::SExtScaledReg ||
AM.Form == ExtAddrMode::Formula::ZExtScaledReg) {
// The new instruction will be in the form `ldr Rt, [Xn, Wm, {s,u}xtw #N]`.
assert(AM.ScaledReg && !AM.Displacement &&
"Address offset can be a register or an immediate, but not both");
unsigned Opcode = offsetExtendOpcode(MemI.getOpcode());
MRI.constrainRegClass(AM.BaseReg, &AArch64::GPR64spRegClass);
// Make sure the offset register is in the correct register class.
Register OffsetReg = AM.ScaledReg;
const TargetRegisterClass *RC = MRI.getRegClass(OffsetReg);
if (RC->hasSuperClassEq(&AArch64::GPR64RegClass)) {
OffsetReg = MRI.createVirtualRegister(&AArch64::GPR32RegClass);
BuildMI(MBB, MemI, DL, get(TargetOpcode::COPY), OffsetReg)
.addReg(AM.ScaledReg, 0, AArch64::sub_32);
}
auto B = BuildMI(MBB, MemI, DL, get(Opcode))
.addReg(MemI.getOperand(0).getReg(),
MemI.mayLoad() ? RegState::Define : 0)
.addReg(AM.BaseReg)
.addReg(OffsetReg)
.addImm(AM.Form == ExtAddrMode::Formula::SExtScaledReg)
.addImm(AM.Scale != 1)
.setMemRefs(MemI.memoperands())
.setMIFlags(MemI.getFlags());
return B.getInstr();
}
llvm_unreachable(
"Function must not be called with an addressing mode it can't handle");
}
bool AArch64InstrInfo::getMemOperandWithOffsetWidth(
const MachineInstr &LdSt, const MachineOperand *&BaseOp, int64_t &Offset,
bool &OffsetIsScalable, TypeSize &Width,
const TargetRegisterInfo *TRI) const {
assert(LdSt.mayLoadOrStore() && "Expected a memory operation.");
// Handle only loads/stores with base register followed by immediate offset.
if (LdSt.getNumExplicitOperands() == 3) {
// Non-paired instruction (e.g., ldr x1, [x0, #8]).
if ((!LdSt.getOperand(1).isReg() && !LdSt.getOperand(1).isFI()) ||
!LdSt.getOperand(2).isImm())
return false;
} else if (LdSt.getNumExplicitOperands() == 4) {
// Paired instruction (e.g., ldp x1, x2, [x0, #8]).
if (!LdSt.getOperand(1).isReg() ||
(!LdSt.getOperand(2).isReg() && !LdSt.getOperand(2).isFI()) ||
!LdSt.getOperand(3).isImm())
return false;
} else
return false;
// Get the scaling factor for the instruction and set the width for the
// instruction.
TypeSize Scale(0U, false);
int64_t Dummy1, Dummy2;
// If this returns false, then it's an instruction we don't want to handle.
if (!getMemOpInfo(LdSt.getOpcode(), Scale, Width, Dummy1, Dummy2))
return false;
// Compute the offset. Offset is calculated as the immediate operand
// multiplied by the scaling factor. Unscaled instructions have scaling factor
// set to 1.
if (LdSt.getNumExplicitOperands() == 3) {
BaseOp = &LdSt.getOperand(1);
Offset = LdSt.getOperand(2).getImm() * Scale.getKnownMinValue();
} else {
assert(LdSt.getNumExplicitOperands() == 4 && "invalid number of operands");
BaseOp = &LdSt.getOperand(2);
Offset = LdSt.getOperand(3).getImm() * Scale.getKnownMinValue();
}
OffsetIsScalable = Scale.isScalable();
if (!BaseOp->isReg() && !BaseOp->isFI())
return false;
return true;
}
MachineOperand &
AArch64InstrInfo::getMemOpBaseRegImmOfsOffsetOperand(MachineInstr &LdSt) const {
assert(LdSt.mayLoadOrStore() && "Expected a memory operation.");
MachineOperand &OfsOp = LdSt.getOperand(LdSt.getNumExplicitOperands() - 1);
assert(OfsOp.isImm() && "Offset operand wasn't immediate.");
return OfsOp;
}
bool AArch64InstrInfo::getMemOpInfo(unsigned Opcode, TypeSize &Scale,
TypeSize &Width, int64_t &MinOffset,
int64_t &MaxOffset) {
switch (Opcode) {
// Not a memory operation or something we want to handle.
default:
Scale = TypeSize::getFixed(0);
Width = TypeSize::getFixed(0);
MinOffset = MaxOffset = 0;
return false;
case AArch64::STRWpost:
case AArch64::LDRWpost:
Width = TypeSize::getFixed(32);
Scale = TypeSize::getFixed(4);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::LDURQi:
case AArch64::STURQi:
Width = TypeSize::getFixed(16);
Scale = TypeSize::getFixed(1);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::PRFUMi:
case AArch64::LDURXi:
case AArch64::LDURDi:
case AArch64::LDAPURXi:
case AArch64::STURXi:
case AArch64::STURDi:
case AArch64::STLURXi:
Width = TypeSize::getFixed(8);
Scale = TypeSize::getFixed(1);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::LDURWi:
case AArch64::LDURSi:
case AArch64::LDURSWi:
case AArch64::LDAPURi:
case AArch64::LDAPURSWi:
case AArch64::STURWi:
case AArch64::STURSi:
case AArch64::STLURWi:
Width = TypeSize::getFixed(4);
Scale = TypeSize::getFixed(1);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::LDURHi:
case AArch64::LDURHHi:
case AArch64::LDURSHXi:
case AArch64::LDURSHWi:
case AArch64::LDAPURHi:
case AArch64::LDAPURSHWi:
case AArch64::LDAPURSHXi:
case AArch64::STURHi:
case AArch64::STURHHi:
case AArch64::STLURHi:
Width = TypeSize::getFixed(2);
Scale = TypeSize::getFixed(1);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::LDURBi:
case AArch64::LDURBBi:
case AArch64::LDURSBXi:
case AArch64::LDURSBWi:
case AArch64::LDAPURBi:
case AArch64::LDAPURSBWi:
case AArch64::LDAPURSBXi:
case AArch64::STURBi:
case AArch64::STURBBi:
case AArch64::STLURBi:
Width = TypeSize::getFixed(1);
Scale = TypeSize::getFixed(1);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::LDPQi:
case AArch64::LDNPQi:
case AArch64::STPQi:
case AArch64::STNPQi:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(32);
MinOffset = -64;
MaxOffset = 63;
break;
case AArch64::LDRQui:
case AArch64::STRQui:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(16);
MinOffset = 0;
MaxOffset = 4095;
break;
case AArch64::LDPXi:
case AArch64::LDPDi:
case AArch64::LDNPXi:
case AArch64::LDNPDi:
case AArch64::STPXi:
case AArch64::STPDi:
case AArch64::STNPXi:
case AArch64::STNPDi:
Scale = TypeSize::getFixed(8);
Width = TypeSize::getFixed(16);
MinOffset = -64;
MaxOffset = 63;
break;
case AArch64::PRFMui:
case AArch64::LDRXui:
case AArch64::LDRDui:
case AArch64::STRXui:
case AArch64::STRDui:
Scale = TypeSize::getFixed(8);
Width = TypeSize::getFixed(8);
MinOffset = 0;
MaxOffset = 4095;
break;
case AArch64::StoreSwiftAsyncContext:
// Store is an STRXui, but there might be an ADDXri in the expansion too.
Scale = TypeSize::getFixed(1);
Width = TypeSize::getFixed(8);
MinOffset = 0;
MaxOffset = 4095;
break;
case AArch64::LDPWi:
case AArch64::LDPSi:
case AArch64::LDNPWi:
case AArch64::LDNPSi:
case AArch64::STPWi:
case AArch64::STPSi:
case AArch64::STNPWi:
case AArch64::STNPSi:
Scale = TypeSize::getFixed(4);
Width = TypeSize::getFixed(8);
MinOffset = -64;
MaxOffset = 63;
break;
case AArch64::LDRWui:
case AArch64::LDRSui:
case AArch64::LDRSWui:
case AArch64::STRWui:
case AArch64::STRSui:
Scale = TypeSize::getFixed(4);
Width = TypeSize::getFixed(4);
MinOffset = 0;
MaxOffset = 4095;
break;
case AArch64::LDRHui:
case AArch64::LDRHHui:
case AArch64::LDRSHWui:
case AArch64::LDRSHXui:
case AArch64::STRHui:
case AArch64::STRHHui:
Scale = TypeSize::getFixed(2);
Width = TypeSize::getFixed(2);
MinOffset = 0;
MaxOffset = 4095;
break;
case AArch64::LDRBui:
case AArch64::LDRBBui:
case AArch64::LDRSBWui:
case AArch64::LDRSBXui:
case AArch64::STRBui:
case AArch64::STRBBui:
Scale = TypeSize::getFixed(1);
Width = TypeSize::getFixed(1);
MinOffset = 0;
MaxOffset = 4095;
break;
case AArch64::STPXpre:
case AArch64::LDPXpost:
case AArch64::STPDpre:
case AArch64::LDPDpost:
Scale = TypeSize::getFixed(8);
Width = TypeSize::getFixed(8);
MinOffset = -512;
MaxOffset = 504;
break;
case AArch64::STPQpre:
case AArch64::LDPQpost:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(16);
MinOffset = -1024;
MaxOffset = 1008;
break;
case AArch64::STRXpre:
case AArch64::STRDpre:
case AArch64::LDRXpost:
case AArch64::LDRDpost:
Scale = TypeSize::getFixed(1);
Width = TypeSize::getFixed(8);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::STRQpre:
case AArch64::LDRQpost:
Scale = TypeSize::getFixed(1);
Width = TypeSize::getFixed(16);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::ADDG:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(0);
MinOffset = 0;
MaxOffset = 63;
break;
case AArch64::TAGPstack:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(0);
// TAGP with a negative offset turns into SUBP, which has a maximum offset
// of 63 (not 64!).
MinOffset = -63;
MaxOffset = 63;
break;
case AArch64::LDG:
case AArch64::STGi:
case AArch64::STZGi:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(16);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::STR_ZZZZXI:
case AArch64::LDR_ZZZZXI:
Scale = TypeSize::getScalable(16);
Width = TypeSize::getScalable(16 * 4);
MinOffset = -256;
MaxOffset = 252;
break;
case AArch64::STR_ZZZXI:
case AArch64::LDR_ZZZXI:
Scale = TypeSize::getScalable(16);
Width = TypeSize::getScalable(16 * 3);
MinOffset = -256;
MaxOffset = 253;
break;
case AArch64::STR_ZZXI:
case AArch64::LDR_ZZXI:
Scale = TypeSize::getScalable(16);
Width = TypeSize::getScalable(16 * 2);
MinOffset = -256;
MaxOffset = 254;
break;
case AArch64::LDR_PXI:
case AArch64::STR_PXI:
Scale = TypeSize::getScalable(2);
Width = TypeSize::getScalable(2);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::LDR_PPXI:
case AArch64::STR_PPXI:
Scale = TypeSize::getScalable(2);
Width = TypeSize::getScalable(2 * 2);
MinOffset = -256;
MaxOffset = 254;
break;
case AArch64::LDR_ZXI:
case AArch64::STR_ZXI:
Scale = TypeSize::getScalable(16);
Width = TypeSize::getScalable(16);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::LD1B_IMM:
case AArch64::LD1H_IMM:
case AArch64::LD1W_IMM:
case AArch64::LD1D_IMM:
case AArch64::LDNT1B_ZRI:
case AArch64::LDNT1H_ZRI:
case AArch64::LDNT1W_ZRI:
case AArch64::LDNT1D_ZRI:
case AArch64::ST1B_IMM:
case AArch64::ST1H_IMM:
case AArch64::ST1W_IMM:
case AArch64::ST1D_IMM:
case AArch64::STNT1B_ZRI:
case AArch64::STNT1H_ZRI:
case AArch64::STNT1W_ZRI:
case AArch64::STNT1D_ZRI:
case AArch64::LDNF1B_IMM:
case AArch64::LDNF1H_IMM:
case AArch64::LDNF1W_IMM:
case AArch64::LDNF1D_IMM:
// A full vectors worth of data
// Width = mbytes * elements
Scale = TypeSize::getScalable(16);
Width = TypeSize::getScalable(16);
MinOffset = -8;
MaxOffset = 7;
break;
case AArch64::LD2B_IMM:
case AArch64::LD2H_IMM:
case AArch64::LD2W_IMM:
case AArch64::LD2D_IMM:
case AArch64::ST2B_IMM:
case AArch64::ST2H_IMM:
case AArch64::ST2W_IMM:
case AArch64::ST2D_IMM:
Scale = TypeSize::getScalable(32);
Width = TypeSize::getScalable(16 * 2);
MinOffset = -8;
MaxOffset = 7;
break;
case AArch64::LD3B_IMM:
case AArch64::LD3H_IMM:
case AArch64::LD3W_IMM:
case AArch64::LD3D_IMM:
case AArch64::ST3B_IMM:
case AArch64::ST3H_IMM:
case AArch64::ST3W_IMM:
case AArch64::ST3D_IMM:
Scale = TypeSize::getScalable(48);
Width = TypeSize::getScalable(16 * 3);
MinOffset = -8;
MaxOffset = 7;
break;
case AArch64::LD4B_IMM:
case AArch64::LD4H_IMM:
case AArch64::LD4W_IMM:
case AArch64::LD4D_IMM:
case AArch64::ST4B_IMM:
case AArch64::ST4H_IMM:
case AArch64::ST4W_IMM:
case AArch64::ST4D_IMM:
Scale = TypeSize::getScalable(64);
Width = TypeSize::getScalable(16 * 4);
MinOffset = -8;
MaxOffset = 7;
break;
case AArch64::LD1B_H_IMM:
case AArch64::LD1SB_H_IMM:
case AArch64::LD1H_S_IMM:
case AArch64::LD1SH_S_IMM:
case AArch64::LD1W_D_IMM:
case AArch64::LD1SW_D_IMM:
case AArch64::ST1B_H_IMM:
case AArch64::ST1H_S_IMM:
case AArch64::ST1W_D_IMM:
case AArch64::LDNF1B_H_IMM:
case AArch64::LDNF1SB_H_IMM:
case AArch64::LDNF1H_S_IMM:
case AArch64::LDNF1SH_S_IMM:
case AArch64::LDNF1W_D_IMM:
case AArch64::LDNF1SW_D_IMM:
// A half vector worth of data
// Width = mbytes * elements
Scale = TypeSize::getScalable(8);
Width = TypeSize::getScalable(8);
MinOffset = -8;
MaxOffset = 7;
break;
case AArch64::LD1B_S_IMM:
case AArch64::LD1SB_S_IMM:
case AArch64::LD1H_D_IMM:
case AArch64::LD1SH_D_IMM:
case AArch64::ST1B_S_IMM:
case AArch64::ST1H_D_IMM:
case AArch64::LDNF1B_S_IMM:
case AArch64::LDNF1SB_S_IMM:
case AArch64::LDNF1H_D_IMM:
case AArch64::LDNF1SH_D_IMM:
// A quarter vector worth of data
// Width = mbytes * elements
Scale = TypeSize::getScalable(4);
Width = TypeSize::getScalable(4);
MinOffset = -8;
MaxOffset = 7;
break;
case AArch64::LD1B_D_IMM:
case AArch64::LD1SB_D_IMM:
case AArch64::ST1B_D_IMM:
case AArch64::LDNF1B_D_IMM:
case AArch64::LDNF1SB_D_IMM:
// A eighth vector worth of data
// Width = mbytes * elements
Scale = TypeSize::getScalable(2);
Width = TypeSize::getScalable(2);
MinOffset = -8;
MaxOffset = 7;
break;
case AArch64::ST2Gi:
case AArch64::STZ2Gi:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(32);
MinOffset = -256;
MaxOffset = 255;
break;
case AArch64::STGPi:
Scale = TypeSize::getFixed(16);
Width = TypeSize::getFixed(16);
MinOffset = -64;
MaxOffset = 63;
break;
case AArch64::LD1RB_IMM:
case AArch64::LD1RB_H_IMM:
case AArch64::LD1RB_S_IMM:
case AArch64::LD1RB_D_IMM:
case AArch64::LD1RSB_H_IMM:
case AArch64::LD1RSB_S_IMM:
case AArch64::LD1RSB_D_IMM:
Scale = TypeSize::getFixed(1);
Width = TypeSize::getFixed(1);
MinOffset = 0;
MaxOffset = 63;
break;
case AArch64::LD1RH_IMM:
case AArch64::LD1RH_S_IMM:
case AArch64::LD1RH_D_IMM:
case AArch64::LD1RSH_S_IMM:
case AArch64::LD1RSH_D_IMM:
Scale = TypeSize::getFixed(2);
Width = TypeSize::getFixed(2);
MinOffset = 0;
MaxOffset = 63;
break;
case AArch64::LD1RW_IMM:
case AArch64::LD1RW_D_IMM:
case AArch64::LD1RSW_IMM:
Scale = TypeSize::getFixed(4);
Width = TypeSize::getFixed(4);
MinOffset = 0;
MaxOffset = 63;
break;
case AArch64::LD1RD_IMM:
Scale = TypeSize::getFixed(8);
Width = TypeSize::getFixed(8);
MinOffset = 0;
MaxOffset = 63;
break;
}
return true;
}
// Scaling factor for unscaled load or store.
int AArch64InstrInfo::getMemScale(unsigned Opc) {
switch (Opc) {
default:
llvm_unreachable("Opcode has unknown scale!");
case AArch64::LDRBBui:
case AArch64::LDURBBi:
case AArch64::LDRSBWui:
case AArch64::LDURSBWi:
case AArch64::STRBBui:
case AArch64::STURBBi:
return 1;
case AArch64::LDRHHui:
case AArch64::LDURHHi:
case AArch64::LDRSHWui:
case AArch64::LDURSHWi:
case AArch64::STRHHui:
case AArch64::STURHHi:
return 2;
case AArch64::LDRSui:
case AArch64::LDURSi:
case AArch64::LDRSpre:
case AArch64::LDRSWui:
case AArch64::LDURSWi:
case AArch64::LDRSWpre:
case AArch64::LDRWpre:
case AArch64::LDRWui:
case AArch64::LDURWi:
case AArch64::STRSui:
case AArch64::STURSi:
case AArch64::STRSpre:
case AArch64::STRWui:
case AArch64::STURWi:
case AArch64::STRWpre:
case AArch64::LDPSi:
case AArch64::LDPSWi:
case AArch64::LDPWi:
case AArch64::STPSi:
case AArch64::STPWi:
return 4;
case AArch64::LDRDui:
case AArch64::LDURDi:
case AArch64::LDRDpre:
case AArch64::LDRXui:
case AArch64::LDURXi:
case AArch64::LDRXpre:
case AArch64::STRDui:
case AArch64::STURDi:
case AArch64::STRDpre:
case AArch64::STRXui:
case AArch64::STURXi:
case AArch64::STRXpre:
case AArch64::LDPDi:
case AArch64::LDPXi:
case AArch64::STPDi:
case AArch64::STPXi:
return 8;
case AArch64::LDRQui:
case AArch64::LDURQi:
case AArch64::STRQui:
case AArch64::STURQi:
case AArch64::STRQpre:
case AArch64::LDPQi:
case AArch64::LDRQpre:
case AArch64::STPQi:
case AArch64::STGi:
case AArch64::STZGi:
case AArch64::ST2Gi:
case AArch64::STZ2Gi:
case AArch64::STGPi:
return 16;
}
}
bool AArch64InstrInfo::isPreLd(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
return false;
case AArch64::LDRWpre:
case AArch64::LDRXpre:
case AArch64::LDRSWpre:
case AArch64::LDRSpre:
case AArch64::LDRDpre:
case AArch64::LDRQpre:
return true;
}
}
bool AArch64InstrInfo::isPreSt(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
return false;
case AArch64::STRWpre:
case AArch64::STRXpre:
case AArch64::STRSpre:
case AArch64::STRDpre:
case AArch64::STRQpre:
return true;
}
}
bool AArch64InstrInfo::isPreLdSt(const MachineInstr &MI) {
return isPreLd(MI) || isPreSt(MI);
}
bool AArch64InstrInfo::isPairedLdSt(const MachineInstr &MI) {
switch (MI.getOpcode()) {
default:
return false;
case AArch64::LDPSi:
case AArch64::LDPSWi:
case AArch64::LDPDi:
case AArch64::LDPQi:
case AArch64::LDPWi:
case AArch64::LDPXi:
case AArch64::STPSi:
case AArch64::STPDi:
case AArch64::STPQi:
case AArch64::STPWi:
case AArch64::STPXi:
case AArch64::STGPi:
return true;
}
}
const MachineOperand &AArch64InstrInfo::getLdStBaseOp(const MachineInstr &MI) {
unsigned Idx =
AArch64InstrInfo::isPairedLdSt(MI) || AArch64InstrInfo::isPreLdSt(MI) ? 2
: 1;
return MI.getOperand(Idx);
}
const MachineOperand &
AArch64InstrInfo::getLdStOffsetOp(const MachineInstr &MI) {
unsigned Idx =
AArch64InstrInfo::isPairedLdSt(MI) || AArch64InstrInfo::isPreLdSt(MI) ? 3
: 2;
return MI.getOperand(Idx);
}
static const TargetRegisterClass *getRegClass(const MachineInstr &MI,
Register Reg) {
if (MI.getParent() == nullptr)
return nullptr;
const MachineFunction *MF = MI.getParent()->getParent();
return MF ? MF->getRegInfo().getRegClassOrNull(Reg) : nullptr;
}
bool AArch64InstrInfo::isHForm(const MachineInstr &MI) {
auto IsHFPR = [&](const MachineOperand &Op) {
if (!Op.isReg())
return false;
auto Reg = Op.getReg();
if (Reg.isPhysical())
return AArch64::FPR16RegClass.contains(Reg);
const TargetRegisterClass *TRC = ::getRegClass(MI, Reg);
return TRC == &AArch64::FPR16RegClass ||
TRC == &AArch64::FPR16_loRegClass;
};
return llvm::any_of(MI.operands(), IsHFPR);
}
bool AArch64InstrInfo::isQForm(const MachineInstr &MI) {
auto IsQFPR = [&](const MachineOperand &Op) {
if (!Op.isReg())
return false;
auto Reg = Op.getReg();
if (Reg.isPhysical())
return AArch64::FPR128RegClass.contains(Reg);
const TargetRegisterClass *TRC = ::getRegClass(MI, Reg);
return TRC == &AArch64::FPR128RegClass ||
TRC == &AArch64::FPR128_loRegClass;
};
return llvm::any_of(MI.operands(), IsQFPR);
}
bool AArch64InstrInfo::hasBTISemantics(const MachineInstr &MI) {
switch (MI.getOpcode()) {
case AArch64::BRK:
case AArch64::HLT:
case AArch64::PACIASP:
case AArch64::PACIBSP:
// Implicit BTI behavior.
return true;
case AArch64::PAUTH_PROLOGUE:
// PAUTH_PROLOGUE expands to PACI(A|B)SP.
return true;
case AArch64::HINT: {
unsigned Imm = MI.getOperand(0).getImm();
// Explicit BTI instruction.
if (Imm == 32 || Imm == 34 || Imm == 36 || Imm == 38)
return true;
// PACI(A|B)SP instructions.
if (Imm == 25 || Imm == 27)
return true;
return false;
}
default:
return false;
}
}
bool AArch64InstrInfo::isFpOrNEON(const MachineInstr &MI) {
auto IsFPR = [&](const MachineOperand &Op) {
if (!Op.isReg())
return false;
auto Reg = Op.getReg();
if (Reg.isPhysical())
return AArch64::FPR128RegClass.contains(Reg) ||
AArch64::FPR64RegClass.contains(Reg) ||
AArch64::FPR32RegClass.contains(Reg) ||
AArch64::FPR16RegClass.contains(Reg) ||
AArch64::FPR8RegClass.contains(Reg);
const TargetRegisterClass *TRC = ::getRegClass(MI, Reg);
return TRC == &AArch64::FPR128RegClass ||
TRC == &AArch64::FPR128_loRegClass ||
TRC == &AArch64::FPR64RegClass ||
TRC == &AArch64::FPR64_loRegClass ||
TRC == &AArch64::FPR32RegClass || TRC == &AArch64::FPR16RegClass ||
TRC == &AArch64::FPR8RegClass;
};
return llvm::any_of(MI.operands(), IsFPR);
}
// Scale the unscaled offsets. Returns false if the unscaled offset can't be
// scaled.
static bool scaleOffset(unsigned Opc, int64_t &Offset) {
int Scale = AArch64InstrInfo::getMemScale(Opc);
// If the byte-offset isn't a multiple of the stride, we can't scale this
// offset.
if (Offset % Scale != 0)
return false;
// Convert the byte-offset used by unscaled into an "element" offset used
// by the scaled pair load/store instructions.
Offset /= Scale;
return true;
}
static bool canPairLdStOpc(unsigned FirstOpc, unsigned SecondOpc) {
if (FirstOpc == SecondOpc)
return true;
// We can also pair sign-ext and zero-ext instructions.
switch (FirstOpc) {
default:
return false;
case AArch64::STRSui:
case AArch64::STURSi:
return SecondOpc == AArch64::STRSui || SecondOpc == AArch64::STURSi;
case AArch64::STRDui:
case AArch64::STURDi:
return SecondOpc == AArch64::STRDui || SecondOpc == AArch64::STURDi;
case AArch64::STRQui:
case AArch64::STURQi:
return SecondOpc == AArch64::STRQui || SecondOpc == AArch64::STURQi;
case AArch64::STRWui:
case AArch64::STURWi:
return SecondOpc == AArch64::STRWui || SecondOpc == AArch64::STURWi;
case AArch64::STRXui:
case AArch64::STURXi:
return SecondOpc == AArch64::STRXui || SecondOpc == AArch64::STURXi;
case AArch64::LDRSui:
case AArch64::LDURSi:
return SecondOpc == AArch64::LDRSui || SecondOpc == AArch64::LDURSi;
case AArch64::LDRDui:
case AArch64::LDURDi:
return SecondOpc == AArch64::LDRDui || SecondOpc == AArch64::LDURDi;
case AArch64::LDRQui:
case AArch64::LDURQi:
return SecondOpc == AArch64::LDRQui || SecondOpc == AArch64::LDURQi;
case AArch64::LDRWui:
case AArch64::LDURWi:
return SecondOpc == AArch64::LDRSWui || SecondOpc == AArch64::LDURSWi;
case AArch64::LDRSWui:
case AArch64::LDURSWi:
return SecondOpc == AArch64::LDRWui || SecondOpc == AArch64::LDURWi;
case AArch64::LDRXui:
case AArch64::LDURXi:
return SecondOpc == AArch64::LDRXui || SecondOpc == AArch64::LDURXi;
}
// These instructions can't be paired based on their opcodes.
return false;
}
static bool shouldClusterFI(const MachineFrameInfo &MFI, int FI1,
int64_t Offset1, unsigned Opcode1, int FI2,
int64_t Offset2, unsigned Opcode2) {
// Accesses through fixed stack object frame indices may access a different
// fixed stack slot. Check that the object offsets + offsets match.
if (MFI.isFixedObjectIndex(FI1) && MFI.isFixedObjectIndex(FI2)) {
int64_t ObjectOffset1 = MFI.getObjectOffset(FI1);
int64_t ObjectOffset2 = MFI.getObjectOffset(FI2);
assert(ObjectOffset1 <= ObjectOffset2 && "Object offsets are not ordered.");
// Convert to scaled object offsets.
int Scale1 = AArch64InstrInfo::getMemScale(Opcode1);
if (ObjectOffset1 % Scale1 != 0)
return false;
ObjectOffset1 /= Scale1;
int Scale2 = AArch64InstrInfo::getMemScale(Opcode2);
if (ObjectOffset2 % Scale2 != 0)
return false;
ObjectOffset2 /= Scale2;
ObjectOffset1 += Offset1;
ObjectOffset2 += Offset2;
return ObjectOffset1 + 1 == ObjectOffset2;
}
return FI1 == FI2;
}
/// Detect opportunities for ldp/stp formation.
///
/// Only called for LdSt for which getMemOperandWithOffset returns true.
bool AArch64InstrInfo::shouldClusterMemOps(
ArrayRef<const MachineOperand *> BaseOps1, int64_t OpOffset1,
bool OffsetIsScalable1, ArrayRef<const MachineOperand *> BaseOps2,
int64_t OpOffset2, bool OffsetIsScalable2, unsigned ClusterSize,
unsigned NumBytes) const {
assert(BaseOps1.size() == 1 && BaseOps2.size() == 1);
const MachineOperand &BaseOp1 = *BaseOps1.front();
const MachineOperand &BaseOp2 = *BaseOps2.front();
const MachineInstr &FirstLdSt = *BaseOp1.getParent();
const MachineInstr &SecondLdSt = *BaseOp2.getParent();
if (BaseOp1.getType() != BaseOp2.getType())
return false;
assert((BaseOp1.isReg() || BaseOp1.isFI()) &&
"Only base registers and frame indices are supported.");
// Check for both base regs and base FI.
if (BaseOp1.isReg() && BaseOp1.getReg() != BaseOp2.getReg())
return false;
// Only cluster up to a single pair.
if (ClusterSize > 2)
return false;
if (!isPairableLdStInst(FirstLdSt) || !isPairableLdStInst(SecondLdSt))
return false;
// Can we pair these instructions based on their opcodes?
unsigned FirstOpc = FirstLdSt.getOpcode();
unsigned SecondOpc = SecondLdSt.getOpcode();
if (!canPairLdStOpc(FirstOpc, SecondOpc))
return false;
// Can't merge volatiles or load/stores that have a hint to avoid pair
// formation, for example.
if (!isCandidateToMergeOrPair(FirstLdSt) ||
!isCandidateToMergeOrPair(SecondLdSt))
return false;
// isCandidateToMergeOrPair guarantees that operand 2 is an immediate.
int64_t Offset1 = FirstLdSt.getOperand(2).getImm();
if (hasUnscaledLdStOffset(FirstOpc) && !scaleOffset(FirstOpc, Offset1))
return false;
int64_t Offset2 = SecondLdSt.getOperand(2).getImm();
if (hasUnscaledLdStOffset(SecondOpc) && !scaleOffset(SecondOpc, Offset2))
return false;
// Pairwise instructions have a 7-bit signed offset field.
if (Offset1 > 63 || Offset1 < -64)
return false;
// The caller should already have ordered First/SecondLdSt by offset.
// Note: except for non-equal frame index bases
if (BaseOp1.isFI()) {
assert((!BaseOp1.isIdenticalTo(BaseOp2) || Offset1 <= Offset2) &&
"Caller should have ordered offsets.");
const MachineFrameInfo &MFI =
FirstLdSt.getParent()->getParent()->getFrameInfo();
return shouldClusterFI(MFI, BaseOp1.getIndex(), Offset1, FirstOpc,
BaseOp2.getIndex(), Offset2, SecondOpc);
}
assert(Offset1 <= Offset2 && "Caller should have ordered offsets.");
return Offset1 + 1 == Offset2;
}
static const MachineInstrBuilder &AddSubReg(const MachineInstrBuilder &MIB,
unsigned Reg, unsigned SubIdx,
unsigned State,
const TargetRegisterInfo *TRI) {
if (!SubIdx)
return MIB.addReg(Reg, State);
if (Register::isPhysicalRegister(Reg))
return MIB.addReg(TRI->getSubReg(Reg, SubIdx), State);
return MIB.addReg(Reg, State, SubIdx);
}
static bool forwardCopyWillClobberTuple(unsigned DestReg, unsigned SrcReg,
unsigned NumRegs) {
// We really want the positive remainder mod 32 here, that happens to be
// easily obtainable with a mask.
return ((DestReg - SrcReg) & 0x1f) < NumRegs;
}
void AArch64InstrInfo::copyPhysRegTuple(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
const DebugLoc &DL, MCRegister DestReg,
MCRegister SrcReg, bool KillSrc,
unsigned Opcode,
ArrayRef<unsigned> Indices) const {
assert(Subtarget.hasNEON() && "Unexpected register copy without NEON");
const TargetRegisterInfo *TRI = &getRegisterInfo();
uint16_t DestEncoding = TRI->getEncodingValue(DestReg);
uint16_t SrcEncoding = TRI->getEncodingValue(SrcReg);
unsigned NumRegs = Indices.size();
int SubReg = 0, End = NumRegs, Incr = 1;
if (forwardCopyWillClobberTuple(DestEncoding, SrcEncoding, NumRegs)) {
SubReg = NumRegs - 1;
End = -1;
Incr = -1;
}
for (; SubReg != End; SubReg += Incr) {
const MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opcode));
AddSubReg(MIB, DestReg, Indices[SubReg], RegState::Define, TRI);
AddSubReg(MIB, SrcReg, Indices[SubReg], 0, TRI);
AddSubReg(MIB, SrcReg, Indices[SubReg], getKillRegState(KillSrc), TRI);
}
}
void AArch64InstrInfo::copyGPRRegTuple(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
DebugLoc DL, unsigned DestReg,
unsigned SrcReg, bool KillSrc,
unsigned Opcode, unsigned ZeroReg,
llvm::ArrayRef<unsigned> Indices) const {
const TargetRegisterInfo *TRI = &getRegisterInfo();
unsigned NumRegs = Indices.size();
#ifndef NDEBUG
uint16_t DestEncoding = TRI->getEncodingValue(DestReg);
uint16_t SrcEncoding = TRI->getEncodingValue(SrcReg);
assert(DestEncoding % NumRegs == 0 && SrcEncoding % NumRegs == 0 &&
"GPR reg sequences should not be able to overlap");
#endif
for (unsigned SubReg = 0; SubReg != NumRegs; ++SubReg) {
const MachineInstrBuilder MIB = BuildMI(MBB, I, DL, get(Opcode));
AddSubReg(MIB, DestReg, Indices[SubReg], RegState::Define, TRI);
MIB.addReg(ZeroReg);
AddSubReg(MIB, SrcReg, Indices[SubReg], getKillRegState(KillSrc), TRI);
MIB.addImm(0);
}
}
void AArch64InstrInfo::copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
const DebugLoc &DL, MCRegister DestReg,
MCRegister SrcReg, bool KillSrc) const {
if (AArch64::GPR32spRegClass.contains(DestReg) &&
(AArch64::GPR32spRegClass.contains(SrcReg) || SrcReg == AArch64::WZR)) {
const TargetRegisterInfo *TRI = &getRegisterInfo();
if (DestReg == AArch64::WSP || SrcReg == AArch64::WSP) {
// If either operand is WSP, expand to ADD #0.
if (Subtarget.hasZeroCycleRegMove()) {
// Cyclone recognizes "ADD Xd, Xn, #0" as a zero-cycle register move.
MCRegister DestRegX = TRI->getMatchingSuperReg(
DestReg, AArch64::sub_32, &AArch64::GPR64spRegClass);
MCRegister SrcRegX = TRI->getMatchingSuperReg(
SrcReg, AArch64::sub_32, &AArch64::GPR64spRegClass);
// This instruction is reading and writing X registers. This may upset
// the register scavenger and machine verifier, so we need to indicate
// that we are reading an undefined value from SrcRegX, but a proper
// value from SrcReg.
BuildMI(MBB, I, DL, get(AArch64::ADDXri), DestRegX)
.addReg(SrcRegX, RegState::Undef)
.addImm(0)
.addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, 0))
.addReg(SrcReg, RegState::Implicit | getKillRegState(KillSrc));
} else {
BuildMI(MBB, I, DL, get(AArch64::ADDWri), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc))
.addImm(0)
.addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, 0));
}
} else if (SrcReg == AArch64::WZR && Subtarget.hasZeroCycleZeroingGP()) {
BuildMI(MBB, I, DL, get(AArch64::MOVZWi), DestReg)
.addImm(0)
.addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, 0));
} else {
if (Subtarget.hasZeroCycleRegMove()) {
// Cyclone recognizes "ORR Xd, XZR, Xm" as a zero-cycle register move.
MCRegister DestRegX = TRI->getMatchingSuperReg(
DestReg, AArch64::sub_32, &AArch64::GPR64spRegClass);
MCRegister SrcRegX = TRI->getMatchingSuperReg(
SrcReg, AArch64::sub_32, &AArch64::GPR64spRegClass);
// This instruction is reading and writing X registers. This may upset
// the register scavenger and machine verifier, so we need to indicate
// that we are reading an undefined value from SrcRegX, but a proper
// value from SrcReg.
BuildMI(MBB, I, DL, get(AArch64::ORRXrr), DestRegX)
.addReg(AArch64::XZR)
.addReg(SrcRegX, RegState::Undef)
.addReg(SrcReg, RegState::Implicit | getKillRegState(KillSrc));
} else {
// Otherwise, expand to ORR WZR.
BuildMI(MBB, I, DL, get(AArch64::ORRWrr), DestReg)
.addReg(AArch64::WZR)
.addReg(SrcReg, getKillRegState(KillSrc));
}
}
return;
}
// Copy a Predicate register by ORRing with itself.
if (AArch64::PPRRegClass.contains(DestReg) &&
AArch64::PPRRegClass.contains(SrcReg)) {
assert(Subtarget.hasSVEorSME() && "Unexpected SVE register.");
BuildMI(MBB, I, DL, get(AArch64::ORR_PPzPP), DestReg)
.addReg(SrcReg) // Pg
.addReg(SrcReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
// Copy a predicate-as-counter register by ORRing with itself as if it
// were a regular predicate (mask) register.
bool DestIsPNR = AArch64::PNRRegClass.contains(DestReg);
bool SrcIsPNR = AArch64::PNRRegClass.contains(SrcReg);
if (DestIsPNR || SrcIsPNR) {
assert((Subtarget.hasSVE2p1() || Subtarget.hasSME2()) &&
"Unexpected predicate-as-counter register.");
auto ToPPR = [](MCRegister R) -> MCRegister {
return (R - AArch64::PN0) + AArch64::P0;
};
MCRegister PPRSrcReg = SrcIsPNR ? ToPPR(SrcReg) : SrcReg;
MCRegister PPRDestReg = DestIsPNR ? ToPPR(DestReg) : DestReg;
if (PPRSrcReg != PPRDestReg) {
auto NewMI = BuildMI(MBB, I, DL, get(AArch64::ORR_PPzPP), PPRDestReg)
.addReg(PPRSrcReg) // Pg
.addReg(PPRSrcReg)
.addReg(PPRSrcReg, getKillRegState(KillSrc));
if (DestIsPNR)
NewMI.addDef(DestReg, RegState::Implicit);
}
return;
}
// Copy a Z register by ORRing with itself.
if (AArch64::ZPRRegClass.contains(DestReg) &&
AArch64::ZPRRegClass.contains(SrcReg)) {
assert(Subtarget.hasSVEorSME() && "Unexpected SVE register.");
BuildMI(MBB, I, DL, get(AArch64::ORR_ZZZ), DestReg)
.addReg(SrcReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
// Copy a Z register pair by copying the individual sub-registers.
if ((AArch64::ZPR2RegClass.contains(DestReg) ||
AArch64::ZPR2StridedOrContiguousRegClass.contains(DestReg)) &&
(AArch64::ZPR2RegClass.contains(SrcReg) ||
AArch64::ZPR2StridedOrContiguousRegClass.contains(SrcReg))) {
assert(Subtarget.hasSVEorSME() && "Unexpected SVE register.");
static const unsigned Indices[] = {AArch64::zsub0, AArch64::zsub1};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORR_ZZZ,
Indices);
return;
}
// Copy a Z register triple by copying the individual sub-registers.
if (AArch64::ZPR3RegClass.contains(DestReg) &&
AArch64::ZPR3RegClass.contains(SrcReg)) {
assert(Subtarget.hasSVEorSME() && "Unexpected SVE register.");
static const unsigned Indices[] = {AArch64::zsub0, AArch64::zsub1,
AArch64::zsub2};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORR_ZZZ,
Indices);
return;
}
// Copy a Z register quad by copying the individual sub-registers.
if ((AArch64::ZPR4RegClass.contains(DestReg) ||
AArch64::ZPR4StridedOrContiguousRegClass.contains(DestReg)) &&
(AArch64::ZPR4RegClass.contains(SrcReg) ||
AArch64::ZPR4StridedOrContiguousRegClass.contains(SrcReg))) {
assert(Subtarget.hasSVEorSME() && "Unexpected SVE register.");
static const unsigned Indices[] = {AArch64::zsub0, AArch64::zsub1,
AArch64::zsub2, AArch64::zsub3};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORR_ZZZ,
Indices);
return;
}
if (AArch64::GPR64spRegClass.contains(DestReg) &&
(AArch64::GPR64spRegClass.contains(SrcReg) || SrcReg == AArch64::XZR)) {
if (DestReg == AArch64::SP || SrcReg == AArch64::SP) {
// If either operand is SP, expand to ADD #0.
BuildMI(MBB, I, DL, get(AArch64::ADDXri), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc))
.addImm(0)
.addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, 0));
} else if (SrcReg == AArch64::XZR && Subtarget.hasZeroCycleZeroingGP()) {
BuildMI(MBB, I, DL, get(AArch64::MOVZXi), DestReg)
.addImm(0)
.addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, 0));
} else {
// Otherwise, expand to ORR XZR.
BuildMI(MBB, I, DL, get(AArch64::ORRXrr), DestReg)
.addReg(AArch64::XZR)
.addReg(SrcReg, getKillRegState(KillSrc));
}
return;
}
// Copy a DDDD register quad by copying the individual sub-registers.
if (AArch64::DDDDRegClass.contains(DestReg) &&
AArch64::DDDDRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::dsub0, AArch64::dsub1,
AArch64::dsub2, AArch64::dsub3};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRv8i8,
Indices);
return;
}
// Copy a DDD register triple by copying the individual sub-registers.
if (AArch64::DDDRegClass.contains(DestReg) &&
AArch64::DDDRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::dsub0, AArch64::dsub1,
AArch64::dsub2};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRv8i8,
Indices);
return;
}
// Copy a DD register pair by copying the individual sub-registers.
if (AArch64::DDRegClass.contains(DestReg) &&
AArch64::DDRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::dsub0, AArch64::dsub1};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRv8i8,
Indices);
return;
}
// Copy a QQQQ register quad by copying the individual sub-registers.
if (AArch64::QQQQRegClass.contains(DestReg) &&
AArch64::QQQQRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::qsub0, AArch64::qsub1,
AArch64::qsub2, AArch64::qsub3};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRv16i8,
Indices);
return;
}
// Copy a QQQ register triple by copying the individual sub-registers.
if (AArch64::QQQRegClass.contains(DestReg) &&
AArch64::QQQRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::qsub0, AArch64::qsub1,
AArch64::qsub2};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRv16i8,
Indices);
return;
}
// Copy a QQ register pair by copying the individual sub-registers.
if (AArch64::QQRegClass.contains(DestReg) &&
AArch64::QQRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::qsub0, AArch64::qsub1};
copyPhysRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRv16i8,
Indices);
return;
}
if (AArch64::XSeqPairsClassRegClass.contains(DestReg) &&
AArch64::XSeqPairsClassRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::sube64, AArch64::subo64};
copyGPRRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRXrs,
AArch64::XZR, Indices);
return;
}
if (AArch64::WSeqPairsClassRegClass.contains(DestReg) &&
AArch64::WSeqPairsClassRegClass.contains(SrcReg)) {
static const unsigned Indices[] = {AArch64::sube32, AArch64::subo32};
copyGPRRegTuple(MBB, I, DL, DestReg, SrcReg, KillSrc, AArch64::ORRWrs,
AArch64::WZR, Indices);
return;
}
if (AArch64::FPR128RegClass.contains(DestReg) &&
AArch64::FPR128RegClass.contains(SrcReg)) {
if (Subtarget.hasSVEorSME() && !Subtarget.isNeonAvailable())
BuildMI(MBB, I, DL, get(AArch64::ORR_ZZZ))
.addReg(AArch64::Z0 + (DestReg - AArch64::Q0), RegState::Define)
.addReg(AArch64::Z0 + (SrcReg - AArch64::Q0))
.addReg(AArch64::Z0 + (SrcReg - AArch64::Q0));
else if (Subtarget.hasNEON())
BuildMI(MBB, I, DL, get(AArch64::ORRv16i8), DestReg)
.addReg(SrcReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else {
BuildMI(MBB, I, DL, get(AArch64::STRQpre))
.addReg(AArch64::SP, RegState::Define)
.addReg(SrcReg, getKillRegState(KillSrc))
.addReg(AArch64::SP)
.addImm(-16);
BuildMI(MBB, I, DL, get(AArch64::LDRQpre))
.addReg(AArch64::SP, RegState::Define)
.addReg(DestReg, RegState::Define)
.addReg(AArch64::SP)
.addImm(16);
}
return;
}
if (AArch64::FPR64RegClass.contains(DestReg) &&
AArch64::FPR64RegClass.contains(SrcReg)) {
BuildMI(MBB, I, DL, get(AArch64::FMOVDr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (AArch64::FPR32RegClass.contains(DestReg) &&
AArch64::FPR32RegClass.contains(SrcReg)) {
BuildMI(MBB, I, DL, get(AArch64::FMOVSr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (AArch64::FPR16RegClass.contains(DestReg) &&
AArch64::FPR16RegClass.contains(SrcReg)) {
DestReg =
RI.getMatchingSuperReg(DestReg, AArch64::hsub, &AArch64::FPR32RegClass);
SrcReg =
RI.getMatchingSuperReg(SrcReg, AArch64::hsub, &AArch64::FPR32RegClass);
BuildMI(MBB, I, DL, get(AArch64::FMOVSr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (AArch64::FPR8RegClass.contains(DestReg) &&
AArch64::FPR8RegClass.contains(SrcReg)) {
DestReg =
RI.getMatchingSuperReg(DestReg, AArch64::bsub, &AArch64::FPR32RegClass);
SrcReg =
RI.getMatchingSuperReg(SrcReg, AArch64::bsub, &AArch64::FPR32RegClass);
BuildMI(MBB, I, DL, get(AArch64::FMOVSr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
// Copies between GPR64 and FPR64.
if (AArch64::FPR64RegClass.contains(DestReg) &&
AArch64::GPR64RegClass.contains(SrcReg)) {
BuildMI(MBB, I, DL, get(AArch64::FMOVXDr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (AArch64::GPR64RegClass.contains(DestReg) &&
AArch64::FPR64RegClass.contains(SrcReg)) {
BuildMI(MBB, I, DL, get(AArch64::FMOVDXr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
// Copies between GPR32 and FPR32.
if (AArch64::FPR32RegClass.contains(DestReg) &&
AArch64::GPR32RegClass.contains(SrcReg)) {
BuildMI(MBB, I, DL, get(AArch64::FMOVWSr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (AArch64::GPR32RegClass.contains(DestReg) &&
AArch64::FPR32RegClass.contains(SrcReg)) {
BuildMI(MBB, I, DL, get(AArch64::FMOVSWr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
return;
}
if (DestReg == AArch64::NZCV) {
assert(AArch64::GPR64RegClass.contains(SrcReg) && "Invalid NZCV copy");
BuildMI(MBB, I, DL, get(AArch64::MSR))
.addImm(AArch64SysReg::NZCV)
.addReg(SrcReg, getKillRegState(KillSrc))
.addReg(AArch64::NZCV, RegState::Implicit | RegState::Define);
return;
}
if (SrcReg == AArch64::NZCV) {
assert(AArch64::GPR64RegClass.contains(DestReg) && "Invalid NZCV copy");
BuildMI(MBB, I, DL, get(AArch64::MRS), DestReg)
.addImm(AArch64SysReg::NZCV)
.addReg(AArch64::NZCV, RegState::Implicit | getKillRegState(KillSrc));
return;
}
#ifndef NDEBUG
const TargetRegisterInfo &TRI = getRegisterInfo();
errs() << TRI.getRegAsmName(DestReg) << " = COPY "
<< TRI.getRegAsmName(SrcReg) << "\n";
#endif
llvm_unreachable("unimplemented reg-to-reg copy");
}
static void storeRegPairToStackSlot(const TargetRegisterInfo &TRI,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator InsertBefore,
const MCInstrDesc &MCID,
Register SrcReg, bool IsKill,
unsigned SubIdx0, unsigned SubIdx1, int FI,
MachineMemOperand *MMO) {
Register SrcReg0 = SrcReg;
Register SrcReg1 = SrcReg;
if (SrcReg.isPhysical()) {
SrcReg0 = TRI.getSubReg(SrcReg, SubIdx0);
SubIdx0 = 0;
SrcReg1 = TRI.getSubReg(SrcReg, SubIdx1);
SubIdx1 = 0;
}
BuildMI(MBB, InsertBefore, DebugLoc(), MCID)
.addReg(SrcReg0, getKillRegState(IsKill), SubIdx0)
.addReg(SrcReg1, getKillRegState(IsKill), SubIdx1)
.addFrameIndex(FI)
.addImm(0)
.addMemOperand(MMO);
}
void AArch64InstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI,
Register SrcReg, bool isKill, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI,
Register VReg) const {
MachineFunction &MF = *MBB.getParent();
MachineFrameInfo &MFI = MF.getFrameInfo();
MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(MF, FI);
MachineMemOperand *MMO =
MF.getMachineMemOperand(PtrInfo, MachineMemOperand::MOStore,
MFI.getObjectSize(FI), MFI.getObjectAlign(FI));
unsigned Opc = 0;
bool Offset = true;
MCRegister PNRReg = MCRegister::NoRegister;
unsigned StackID = TargetStackID::Default;
switch (TRI->getSpillSize(*RC)) {
case 1:
if (AArch64::FPR8RegClass.hasSubClassEq(RC))
Opc = AArch64::STRBui;
break;
case 2: {
bool IsPNR = AArch64::PNRRegClass.hasSubClassEq(RC);
if (AArch64::FPR16RegClass.hasSubClassEq(RC))
Opc = AArch64::STRHui;
else if (IsPNR || AArch64::PPRRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register store without SVE store instructions");
assert((!IsPNR || Subtarget.hasSVE2p1() || Subtarget.hasSME2()) &&
"Unexpected register store without SVE2p1 or SME2");
Opc = AArch64::STR_PXI;
StackID = TargetStackID::ScalableVector;
}
break;
}
case 4:
if (AArch64::GPR32allRegClass.hasSubClassEq(RC)) {
Opc = AArch64::STRWui;
if (SrcReg.isVirtual())
MF.getRegInfo().constrainRegClass(SrcReg, &AArch64::GPR32RegClass);
else
assert(SrcReg != AArch64::WSP);
} else if (AArch64::FPR32RegClass.hasSubClassEq(RC))
Opc = AArch64::STRSui;
else if (AArch64::PPR2RegClass.hasSubClassEq(RC)) {
Opc = AArch64::STR_PPXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 8:
if (AArch64::GPR64allRegClass.hasSubClassEq(RC)) {
Opc = AArch64::STRXui;
if (SrcReg.isVirtual())
MF.getRegInfo().constrainRegClass(SrcReg, &AArch64::GPR64RegClass);
else
assert(SrcReg != AArch64::SP);
} else if (AArch64::FPR64RegClass.hasSubClassEq(RC)) {
Opc = AArch64::STRDui;
} else if (AArch64::WSeqPairsClassRegClass.hasSubClassEq(RC)) {
storeRegPairToStackSlot(getRegisterInfo(), MBB, MBBI,
get(AArch64::STPWi), SrcReg, isKill,
AArch64::sube32, AArch64::subo32, FI, MMO);
return;
}
break;
case 16:
if (AArch64::FPR128RegClass.hasSubClassEq(RC))
Opc = AArch64::STRQui;
else if (AArch64::DDRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register store without NEON");
Opc = AArch64::ST1Twov1d;
Offset = false;
} else if (AArch64::XSeqPairsClassRegClass.hasSubClassEq(RC)) {
storeRegPairToStackSlot(getRegisterInfo(), MBB, MBBI,
get(AArch64::STPXi), SrcReg, isKill,
AArch64::sube64, AArch64::subo64, FI, MMO);
return;
} else if (AArch64::ZPRRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register store without SVE store instructions");
Opc = AArch64::STR_ZXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 24:
if (AArch64::DDDRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register store without NEON");
Opc = AArch64::ST1Threev1d;
Offset = false;
}
break;
case 32:
if (AArch64::DDDDRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register store without NEON");
Opc = AArch64::ST1Fourv1d;
Offset = false;
} else if (AArch64::QQRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register store without NEON");
Opc = AArch64::ST1Twov2d;
Offset = false;
} else if (AArch64::ZPR2RegClass.hasSubClassEq(RC) ||
AArch64::ZPR2StridedOrContiguousRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register store without SVE store instructions");
Opc = AArch64::STR_ZZXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 48:
if (AArch64::QQQRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register store without NEON");
Opc = AArch64::ST1Threev2d;
Offset = false;
} else if (AArch64::ZPR3RegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register store without SVE store instructions");
Opc = AArch64::STR_ZZZXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 64:
if (AArch64::QQQQRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register store without NEON");
Opc = AArch64::ST1Fourv2d;
Offset = false;
} else if (AArch64::ZPR4RegClass.hasSubClassEq(RC) ||
AArch64::ZPR4StridedOrContiguousRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register store without SVE store instructions");
Opc = AArch64::STR_ZZZZXI;
StackID = TargetStackID::ScalableVector;
}
break;
}
assert(Opc && "Unknown register class");
MFI.setStackID(FI, StackID);
const MachineInstrBuilder MI = BuildMI(MBB, MBBI, DebugLoc(), get(Opc))
.addReg(SrcReg, getKillRegState(isKill))
.addFrameIndex(FI);
if (Offset)
MI.addImm(0);
if (PNRReg.isValid())
MI.addDef(PNRReg, RegState::Implicit);
MI.addMemOperand(MMO);
}
static void loadRegPairFromStackSlot(const TargetRegisterInfo &TRI,
MachineBasicBlock &MBB,
MachineBasicBlock::iterator InsertBefore,
const MCInstrDesc &MCID,
Register DestReg, unsigned SubIdx0,
unsigned SubIdx1, int FI,
MachineMemOperand *MMO) {
Register DestReg0 = DestReg;
Register DestReg1 = DestReg;
bool IsUndef = true;
if (DestReg.isPhysical()) {
DestReg0 = TRI.getSubReg(DestReg, SubIdx0);
SubIdx0 = 0;
DestReg1 = TRI.getSubReg(DestReg, SubIdx1);
SubIdx1 = 0;
IsUndef = false;
}
BuildMI(MBB, InsertBefore, DebugLoc(), MCID)
.addReg(DestReg0, RegState::Define | getUndefRegState(IsUndef), SubIdx0)
.addReg(DestReg1, RegState::Define | getUndefRegState(IsUndef), SubIdx1)
.addFrameIndex(FI)
.addImm(0)
.addMemOperand(MMO);
}
void AArch64InstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI,
Register DestReg, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI,
Register VReg) const {
MachineFunction &MF = *MBB.getParent();
MachineFrameInfo &MFI = MF.getFrameInfo();
MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(MF, FI);
MachineMemOperand *MMO =
MF.getMachineMemOperand(PtrInfo, MachineMemOperand::MOLoad,
MFI.getObjectSize(FI), MFI.getObjectAlign(FI));
unsigned Opc = 0;
bool Offset = true;
unsigned StackID = TargetStackID::Default;
Register PNRReg = MCRegister::NoRegister;
switch (TRI->getSpillSize(*RC)) {
case 1:
if (AArch64::FPR8RegClass.hasSubClassEq(RC))
Opc = AArch64::LDRBui;
break;
case 2: {
bool IsPNR = AArch64::PNRRegClass.hasSubClassEq(RC);
if (AArch64::FPR16RegClass.hasSubClassEq(RC))
Opc = AArch64::LDRHui;
else if (IsPNR || AArch64::PPRRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register load without SVE load instructions");
assert((!IsPNR || Subtarget.hasSVE2p1() || Subtarget.hasSME2()) &&
"Unexpected register load without SVE2p1 or SME2");
if (IsPNR)
PNRReg = DestReg;
Opc = AArch64::LDR_PXI;
StackID = TargetStackID::ScalableVector;
}
break;
}
case 4:
if (AArch64::GPR32allRegClass.hasSubClassEq(RC)) {
Opc = AArch64::LDRWui;
if (DestReg.isVirtual())
MF.getRegInfo().constrainRegClass(DestReg, &AArch64::GPR32RegClass);
else
assert(DestReg != AArch64::WSP);
} else if (AArch64::FPR32RegClass.hasSubClassEq(RC))
Opc = AArch64::LDRSui;
else if (AArch64::PPR2RegClass.hasSubClassEq(RC)) {
Opc = AArch64::LDR_PPXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 8:
if (AArch64::GPR64allRegClass.hasSubClassEq(RC)) {
Opc = AArch64::LDRXui;
if (DestReg.isVirtual())
MF.getRegInfo().constrainRegClass(DestReg, &AArch64::GPR64RegClass);
else
assert(DestReg != AArch64::SP);
} else if (AArch64::FPR64RegClass.hasSubClassEq(RC)) {
Opc = AArch64::LDRDui;
} else if (AArch64::WSeqPairsClassRegClass.hasSubClassEq(RC)) {
loadRegPairFromStackSlot(getRegisterInfo(), MBB, MBBI,
get(AArch64::LDPWi), DestReg, AArch64::sube32,
AArch64::subo32, FI, MMO);
return;
}
break;
case 16:
if (AArch64::FPR128RegClass.hasSubClassEq(RC))
Opc = AArch64::LDRQui;
else if (AArch64::DDRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register load without NEON");
Opc = AArch64::LD1Twov1d;
Offset = false;
} else if (AArch64::XSeqPairsClassRegClass.hasSubClassEq(RC)) {
loadRegPairFromStackSlot(getRegisterInfo(), MBB, MBBI,
get(AArch64::LDPXi), DestReg, AArch64::sube64,
AArch64::subo64, FI, MMO);
return;
} else if (AArch64::ZPRRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register load without SVE load instructions");
Opc = AArch64::LDR_ZXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 24:
if (AArch64::DDDRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register load without NEON");
Opc = AArch64::LD1Threev1d;
Offset = false;
}
break;
case 32:
if (AArch64::DDDDRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register load without NEON");
Opc = AArch64::LD1Fourv1d;
Offset = false;
} else if (AArch64::QQRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register load without NEON");
Opc = AArch64::LD1Twov2d;
Offset = false;
} else if (AArch64::ZPR2RegClass.hasSubClassEq(RC) ||
AArch64::ZPR2StridedOrContiguousRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register load without SVE load instructions");
Opc = AArch64::LDR_ZZXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 48:
if (AArch64::QQQRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register load without NEON");
Opc = AArch64::LD1Threev2d;
Offset = false;
} else if (AArch64::ZPR3RegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register load without SVE load instructions");
Opc = AArch64::LDR_ZZZXI;
StackID = TargetStackID::ScalableVector;
}
break;
case 64:
if (AArch64::QQQQRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasNEON() && "Unexpected register load without NEON");
Opc = AArch64::LD1Fourv2d;
Offset = false;
} else if (AArch64::ZPR4RegClass.hasSubClassEq(RC) ||
AArch64::ZPR4StridedOrContiguousRegClass.hasSubClassEq(RC)) {
assert(Subtarget.hasSVEorSME() &&
"Unexpected register load without SVE load instructions");
Opc = AArch64::LDR_ZZZZXI;
StackID = TargetStackID::ScalableVector;
}
break;
}
assert(Opc && "Unknown register class");
MFI.setStackID(FI, StackID);
const MachineInstrBuilder MI = BuildMI(MBB, MBBI, DebugLoc(), get(Opc))
.addReg(DestReg, getDefRegState(true))
.addFrameIndex(FI);
if (Offset)
MI.addImm(0);
if (PNRReg.isValid() && !PNRReg.isVirtual())
MI.addDef(PNRReg, RegState::Implicit);
MI.addMemOperand(MMO);
if (PNRReg.isValid() && PNRReg.isVirtual())
BuildMI(MBB, MBBI, DebugLoc(), get(TargetOpcode::COPY), PNRReg)
.addReg(DestReg);
}
bool llvm::isNZCVTouchedInInstructionRange(const MachineInstr &DefMI,
const MachineInstr &UseMI,
const TargetRegisterInfo *TRI) {
return any_of(instructionsWithoutDebug(std::next(DefMI.getIterator()),
UseMI.getIterator()),
[TRI](const MachineInstr &I) {
return I.modifiesRegister(AArch64::NZCV, TRI) ||
I.readsRegister(AArch64::NZCV, TRI);
});
}
void AArch64InstrInfo::decomposeStackOffsetForDwarfOffsets(
const StackOffset &Offset, int64_t &ByteSized, int64_t &VGSized) {
// The smallest scalable element supported by scaled SVE addressing
// modes are predicates, which are 2 scalable bytes in size. So the scalable
// byte offset must always be a multiple of 2.
assert(Offset.getScalable() % 2 == 0 && "Invalid frame offset");
// VGSized offsets are divided by '2', because the VG register is the
// the number of 64bit granules as opposed to 128bit vector chunks,
// which is how the 'n' in e.g. MVT::nxv1i8 is modelled.
// So, for a stack offset of 16 MVT::nxv1i8's, the size is n x 16 bytes.
// VG = n * 2 and the dwarf offset must be VG * 8 bytes.
ByteSized = Offset.getFixed();
VGSized = Offset.getScalable() / 2;
}
/// Returns the offset in parts to which this frame offset can be
/// decomposed for the purpose of describing a frame offset.
/// For non-scalable offsets this is simply its byte size.
void AArch64InstrInfo::decomposeStackOffsetForFrameOffsets(
const StackOffset &Offset, int64_t &NumBytes, int64_t &NumPredicateVectors,
int64_t &NumDataVectors) {
// The smallest scalable element supported by scaled SVE addressing
// modes are predicates, which are 2 scalable bytes in size. So the scalable
// byte offset must always be a multiple of 2.
assert(Offset.getScalable() % 2 == 0 && "Invalid frame offset");
NumBytes = Offset.getFixed();
NumDataVectors = 0;
NumPredicateVectors = Offset.getScalable() / 2;
// This method is used to get the offsets to adjust the frame offset.
// If the function requires ADDPL to be used and needs more than two ADDPL
// instructions, part of the offset is folded into NumDataVectors so that it
// uses ADDVL for part of it, reducing the number of ADDPL instructions.
if (NumPredicateVectors % 8 == 0 || NumPredicateVectors < -64 ||
NumPredicateVectors > 62) {
NumDataVectors = NumPredicateVectors / 8;
NumPredicateVectors -= NumDataVectors * 8;
}
}
// Convenience function to create a DWARF expression for
// Expr + NumBytes + NumVGScaledBytes * AArch64::VG
static void appendVGScaledOffsetExpr(SmallVectorImpl<char> &Expr, int NumBytes,
int NumVGScaledBytes, unsigned VG,
llvm::raw_string_ostream &Comment) {
uint8_t buffer[16];
if (NumBytes) {
Expr.push_back(dwarf::DW_OP_consts);
Expr.append(buffer, buffer + encodeSLEB128(NumBytes, buffer));
Expr.push_back((uint8_t)dwarf::DW_OP_plus);
Comment << (NumBytes < 0 ? " - " : " + ") << std::abs(NumBytes);
}
if (NumVGScaledBytes) {
Expr.push_back((uint8_t)dwarf::DW_OP_consts);
Expr.append(buffer, buffer + encodeSLEB128(NumVGScaledBytes, buffer));
Expr.push_back((uint8_t)dwarf::DW_OP_bregx);
Expr.append(buffer, buffer + encodeULEB128(VG, buffer));
Expr.push_back(0);
Expr.push_back((uint8_t)dwarf::DW_OP_mul);
Expr.push_back((uint8_t)dwarf::DW_OP_plus);
Comment << (NumVGScaledBytes < 0 ? " - " : " + ")
<< std::abs(NumVGScaledBytes) << " * VG";
}
}
// Creates an MCCFIInstruction:
// { DW_CFA_def_cfa_expression, ULEB128 (sizeof expr), expr }
static MCCFIInstruction createDefCFAExpression(const TargetRegisterInfo &TRI,
unsigned Reg,
const StackOffset &Offset) {
int64_t NumBytes, NumVGScaledBytes;
AArch64InstrInfo::decomposeStackOffsetForDwarfOffsets(Offset, NumBytes,
NumVGScaledBytes);
std::string CommentBuffer;
llvm::raw_string_ostream Comment(CommentBuffer);
if (Reg == AArch64::SP)
Comment << "sp";
else if (Reg == AArch64::FP)
Comment << "fp";
else
Comment << printReg(Reg, &TRI);
// Build up the expression (Reg + NumBytes + NumVGScaledBytes * AArch64::VG)
SmallString<64> Expr;
unsigned DwarfReg = TRI.getDwarfRegNum(Reg, true);
Expr.push_back((uint8_t)(dwarf::DW_OP_breg0 + DwarfReg));
Expr.push_back(0);
appendVGScaledOffsetExpr(Expr, NumBytes, NumVGScaledBytes,
TRI.getDwarfRegNum(AArch64::VG, true), Comment);
// Wrap this into DW_CFA_def_cfa.
SmallString<64> DefCfaExpr;
DefCfaExpr.push_back(dwarf::DW_CFA_def_cfa_expression);
uint8_t buffer[16];
DefCfaExpr.append(buffer, buffer + encodeULEB128(Expr.size(), buffer));
DefCfaExpr.append(Expr.str());
return MCCFIInstruction::createEscape(nullptr, DefCfaExpr.str(), SMLoc(),
Comment.str());
}
MCCFIInstruction llvm::createDefCFA(const TargetRegisterInfo &TRI,
unsigned FrameReg, unsigned Reg,
const StackOffset &Offset,
bool LastAdjustmentWasScalable) {
if (Offset.getScalable())
return createDefCFAExpression(TRI, Reg, Offset);
if (FrameReg == Reg && !LastAdjustmentWasScalable)
return MCCFIInstruction::cfiDefCfaOffset(nullptr, int(Offset.getFixed()));
unsigned DwarfReg = TRI.getDwarfRegNum(Reg, true);
return MCCFIInstruction::cfiDefCfa(nullptr, DwarfReg, (int)Offset.getFixed());
}
MCCFIInstruction llvm::createCFAOffset(const TargetRegisterInfo &TRI,
unsigned Reg,
const StackOffset &OffsetFromDefCFA) {
int64_t NumBytes, NumVGScaledBytes;
AArch64InstrInfo::decomposeStackOffsetForDwarfOffsets(
OffsetFromDefCFA, NumBytes, NumVGScaledBytes);
unsigned DwarfReg = TRI.getDwarfRegNum(Reg, true);
// Non-scalable offsets can use DW_CFA_offset directly.
if (!NumVGScaledBytes)
return MCCFIInstruction::createOffset(nullptr, DwarfReg, NumBytes);
std::string CommentBuffer;
llvm::raw_string_ostream Comment(CommentBuffer);
Comment << printReg(Reg, &TRI) << " @ cfa";
// Build up expression (NumBytes + NumVGScaledBytes * AArch64::VG)
SmallString<64> OffsetExpr;
appendVGScaledOffsetExpr(OffsetExpr, NumBytes, NumVGScaledBytes,
TRI.getDwarfRegNum(AArch64::VG, true), Comment);
// Wrap this into DW_CFA_expression
SmallString<64> CfaExpr;
CfaExpr.push_back(dwarf::DW_CFA_expression);
uint8_t buffer[16];
CfaExpr.append(buffer, buffer + encodeULEB128(DwarfReg, buffer));
CfaExpr.append(buffer, buffer + encodeULEB128(OffsetExpr.size(), buffer));
CfaExpr.append(OffsetExpr.str());
return MCCFIInstruction::createEscape(nullptr, CfaExpr.str(), SMLoc(),
Comment.str());
}
// Helper function to emit a frame offset adjustment from a given
// pointer (SrcReg), stored into DestReg. This function is explicit
// in that it requires the opcode.
static void emitFrameOffsetAdj(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI,
const DebugLoc &DL, unsigned DestReg,
unsigned SrcReg, int64_t Offset, unsigned Opc,
const TargetInstrInfo *TII,
MachineInstr::MIFlag Flag, bool NeedsWinCFI,
bool *HasWinCFI, bool EmitCFAOffset,
StackOffset CFAOffset, unsigned FrameReg) {
int Sign = 1;
unsigned MaxEncoding, ShiftSize;
switch (Opc) {
case AArch64::ADDXri:
case AArch64::ADDSXri:
case AArch64::SUBXri:
case AArch64::SUBSXri:
MaxEncoding = 0xfff;
ShiftSize = 12;
break;
case AArch64::ADDVL_XXI:
case AArch64::ADDPL_XXI:
case AArch64::ADDSVL_XXI:
case AArch64::ADDSPL_XXI:
MaxEncoding = 31;
ShiftSize = 0;
if (Offset < 0) {
MaxEncoding = 32;
Sign = -1;
Offset = -Offset;
}
break;
default:
llvm_unreachable("Unsupported opcode");
}
// `Offset` can be in bytes or in "scalable bytes".
int VScale = 1;
if (Opc == AArch64::ADDVL_XXI || Opc == AArch64::ADDSVL_XXI)
VScale = 16;
else if (Opc == AArch64::ADDPL_XXI || Opc == AArch64::ADDSPL_XXI)
VScale = 2;
// FIXME: If the offset won't fit in 24-bits, compute the offset into a
// scratch register. If DestReg is a virtual register, use it as the
// scratch register; otherwise, create a new virtual register (to be
// replaced by the scavenger at the end of PEI). That case can be optimized
// slightly if DestReg is SP which is always 16-byte aligned, so the scratch
// register can be loaded with offset%8 and the add/sub can use an extending
// instruction with LSL#3.
// Currently the function handles any offsets but generates a poor sequence
// of code.
// assert(Offset < (1 << 24) && "unimplemented reg plus immediate");
const unsigned MaxEncodableValue = MaxEncoding << ShiftSize;
Register TmpReg = DestReg;
if (TmpReg == AArch64::XZR)
TmpReg = MBB.getParent()->getRegInfo().createVirtualRegister(
&AArch64::GPR64RegClass);
do {
uint64_t ThisVal = std::min<uint64_t>(Offset, MaxEncodableValue);
unsigned LocalShiftSize = 0;
if (ThisVal > MaxEncoding) {
ThisVal = ThisVal >> ShiftSize;
LocalShiftSize = ShiftSize;
}
assert((ThisVal >> ShiftSize) <= MaxEncoding &&
"Encoding cannot handle value that big");
Offset -= ThisVal << LocalShiftSize;
if (Offset == 0)
TmpReg = DestReg;
auto MBI = BuildMI(MBB, MBBI, DL, TII->get(Opc), TmpReg)
.addReg(SrcReg)
.addImm(Sign * (int)ThisVal);
if (ShiftSize)
MBI = MBI.addImm(
AArch64_AM::getShifterImm(AArch64_AM::LSL, LocalShiftSize));
MBI = MBI.setMIFlag(Flag);
auto Change =
VScale == 1
? StackOffset::getFixed(ThisVal << LocalShiftSize)
: StackOffset::getScalable(VScale * (ThisVal << LocalShiftSize));
if (Sign == -1 || Opc == AArch64::SUBXri || Opc == AArch64::SUBSXri)
CFAOffset += Change;
else
CFAOffset -= Change;
if (EmitCFAOffset && DestReg == TmpReg) {
MachineFunction &MF = *MBB.getParent();
const TargetSubtargetInfo &STI = MF.getSubtarget();
const TargetRegisterInfo &TRI = *STI.getRegisterInfo();
unsigned CFIIndex = MF.addFrameInst(
createDefCFA(TRI, FrameReg, DestReg, CFAOffset, VScale != 1));
BuildMI(MBB, MBBI, DL, TII->get(TargetOpcode::CFI_INSTRUCTION))
.addCFIIndex(CFIIndex)
.setMIFlags(Flag);
}
if (NeedsWinCFI) {
assert(Sign == 1 && "SEH directives should always have a positive sign");
int Imm = (int)(ThisVal << LocalShiftSize);
if ((DestReg == AArch64::FP && SrcReg == AArch64::SP) ||
(SrcReg == AArch64::FP && DestReg == AArch64::SP)) {
if (HasWinCFI)
*HasWinCFI = true;
if (Imm == 0)
BuildMI(MBB, MBBI, DL, TII->get(AArch64::SEH_SetFP)).setMIFlag(Flag);
else
BuildMI(MBB, MBBI, DL, TII->get(AArch64::SEH_AddFP))
.addImm(Imm)
.setMIFlag(Flag);
assert(Offset == 0 && "Expected remaining offset to be zero to "
"emit a single SEH directive");
} else if (DestReg == AArch64::SP) {
if (HasWinCFI)
*HasWinCFI = true;
assert(SrcReg == AArch64::SP && "Unexpected SrcReg for SEH_StackAlloc");
BuildMI(MBB, MBBI, DL, TII->get(AArch64::SEH_StackAlloc))
.addImm(Imm)
.setMIFlag(Flag);
}
}
SrcReg = TmpReg;
} while (Offset);
}
void llvm::emitFrameOffset(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MBBI, const DebugLoc &DL,
unsigned DestReg, unsigned SrcReg,
StackOffset Offset, const TargetInstrInfo *TII,
MachineInstr::MIFlag Flag, bool SetNZCV,
bool NeedsWinCFI, bool *HasWinCFI,
bool EmitCFAOffset, StackOffset CFAOffset,
unsigned FrameReg) {
// If a function is marked as arm_locally_streaming, then the runtime value of
// vscale in the prologue/epilogue is different the runtime value of vscale
// in the function's body. To avoid having to consider multiple vscales,
// we can use `addsvl` to allocate any scalable stack-slots, which under
// most circumstances will be only locals, not callee-save slots.
const Function &F = MBB.getParent()->getFunction();
bool UseSVL = F.hasFnAttribute("aarch64_pstate_sm_body");
int64_t Bytes, NumPredicateVectors, NumDataVectors;
AArch64InstrInfo::decomposeStackOffsetForFrameOffsets(
Offset, Bytes, NumPredicateVectors, NumDataVectors);
// First emit non-scalable frame offsets, or a simple 'mov'.
if (Bytes || (!Offset && SrcReg != DestReg)) {
assert((DestReg != AArch64::SP || Bytes % 8 == 0) &&
"SP increment/decrement not 8-byte aligned");
unsigned Opc = SetNZCV ? AArch64::ADDSXri : AArch64::ADDXri;
if (Bytes < 0) {
Bytes = -Bytes;
Opc = SetNZCV ? AArch64::SUBSXri : AArch64::SUBXri;
}
emitFrameOffsetAdj(MBB, MBBI, DL, DestReg, SrcReg, Bytes, Opc, TII, Flag,
NeedsWinCFI, HasWinCFI, EmitCFAOffset, CFAOffset,
FrameReg);
CFAOffset += (Opc == AArch64::ADDXri || Opc == AArch64::ADDSXri)
? StackOffset::getFixed(-Bytes)
: StackOffset::getFixed(Bytes);
SrcReg = DestReg;
FrameReg = DestReg;
}
assert(!(SetNZCV && (NumPredicateVectors || NumDataVectors)) &&
"SetNZCV not supported with SVE vectors");
assert(!(NeedsWinCFI && (NumPredicateVectors || NumDataVectors)) &&
"WinCFI not supported with SVE vectors");
if (NumDataVectors) {
emitFrameOffsetAdj(MBB, MBBI, DL, DestReg, SrcReg, NumDataVectors,
UseSVL ? AArch64::ADDSVL_XXI : AArch64::ADDVL_XXI,
TII, Flag, NeedsWinCFI, nullptr, EmitCFAOffset,
CFAOffset, FrameReg);
CFAOffset += StackOffset::getScalable(-NumDataVectors * 16);
SrcReg = DestReg;
}
if (NumPredicateVectors) {
assert(DestReg != AArch64::SP && "Unaligned access to SP");
emitFrameOffsetAdj(MBB, MBBI, DL, DestReg, SrcReg, NumPredicateVectors,
UseSVL ? AArch64::ADDSPL_XXI : AArch64::ADDPL_XXI,
TII, Flag, NeedsWinCFI, nullptr, EmitCFAOffset,
CFAOffset, FrameReg);
}
}
MachineInstr *AArch64InstrInfo::foldMemoryOperandImpl(
MachineFunction &MF, MachineInstr &MI, ArrayRef<unsigned> Ops,
MachineBasicBlock::iterator InsertPt, int FrameIndex,
LiveIntervals *LIS, VirtRegMap *VRM) const {
// This is a bit of a hack. Consider this instruction:
//
// %0 = COPY %sp; GPR64all:%0
//
// We explicitly chose GPR64all for the virtual register so such a copy might
// be eliminated by RegisterCoalescer. However, that may not be possible, and
// %0 may even spill. We can't spill %sp, and since it is in the GPR64all
// register class, TargetInstrInfo::foldMemoryOperand() is going to try.
//
// To prevent that, we are going to constrain the %0 register class here.
if (MI.isFullCopy()) {
Register DstReg = MI.getOperand(0).getReg();
Register SrcReg = MI.getOperand(1).getReg();
if (SrcReg == AArch64::SP && DstReg.isVirtual()) {
MF.getRegInfo().constrainRegClass(DstReg, &AArch64::GPR64RegClass);
return nullptr;
}
if (DstReg == AArch64::SP && SrcReg.isVirtual()) {
MF.getRegInfo().constrainRegClass(SrcReg, &AArch64::GPR64RegClass);
return nullptr;
}
// Nothing can folded with copy from/to NZCV.
if (SrcReg == AArch64::NZCV || DstReg == AArch64::NZCV)
return nullptr;
}
// Handle the case where a copy is being spilled or filled but the source
// and destination register class don't match. For example:
//
// %0 = COPY %xzr; GPR64common:%0
//
// In this case we can still safely fold away the COPY and generate the
// following spill code:
//
// STRXui %xzr, %stack.0
//
// This also eliminates spilled cross register class COPYs (e.g. between x and
// d regs) of the same size. For example:
//
// %0 = COPY %1; GPR64:%0, FPR64:%1
//
// will be filled as
//
// LDRDui %0, fi<#0>
//
// instead of
//
// LDRXui %Temp, fi<#0>
// %0 = FMOV %Temp
//
if (MI.isCopy() && Ops.size() == 1 &&
// Make sure we're only folding the explicit COPY defs/uses.
(Ops[0] == 0 || Ops[0] == 1)) {
bool IsSpill = Ops[0] == 0;
bool IsFill = !IsSpill;
const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
const MachineRegisterInfo &MRI = MF.getRegInfo();
MachineBasicBlock &MBB = *MI.getParent();
const MachineOperand &DstMO = MI.getOperand(0);
const MachineOperand &SrcMO = MI.getOperand(1);
Register DstReg = DstMO.getReg();
Register SrcReg = SrcMO.getReg();
// This is slightly expensive to compute for physical regs since
// getMinimalPhysRegClass is slow.
auto getRegClass = [&](unsigned Reg) {
return Register::isVirtualRegister(Reg) ? MRI.getRegClass(Reg)
: TRI.getMinimalPhysRegClass(Reg);
};
if (DstMO.getSubReg() == 0 && SrcMO.getSubReg() == 0) {
assert(TRI.getRegSizeInBits(*getRegClass(DstReg)) ==
TRI.getRegSizeInBits(*getRegClass(SrcReg)) &&
"Mismatched register size in non subreg COPY");
if (IsSpill)
storeRegToStackSlot(MBB, InsertPt, SrcReg, SrcMO.isKill(), FrameIndex,
getRegClass(SrcReg), &TRI, Register());
else
loadRegFromStackSlot(MBB, InsertPt, DstReg, FrameIndex,
getRegClass(DstReg), &TRI, Register());
return &*--InsertPt;
}
// Handle cases like spilling def of:
//
// %0:sub_32<def,read-undef> = COPY %wzr; GPR64common:%0
//
// where the physical register source can be widened and stored to the full
// virtual reg destination stack slot, in this case producing:
//
// STRXui %xzr, %stack.0
//
if (IsSpill && DstMO.isUndef() && SrcReg == AArch64::WZR &&
TRI.getRegSizeInBits(*getRegClass(DstReg)) == 64) {
assert(SrcMO.getSubReg() == 0 &&
"Unexpected subreg on physical register");
storeRegToStackSlot(MBB, InsertPt, AArch64::XZR, SrcMO.isKill(),
FrameIndex, &AArch64::GPR64RegClass, &TRI,
Register());
return &*--InsertPt;
}
// Handle cases like filling use of:
//
// %0:sub_32<def,read-undef> = COPY %1; GPR64:%0, GPR32:%1
//
// where we can load the full virtual reg source stack slot, into the subreg
// destination, in this case producing:
//
// LDRWui %0:sub_32<def,read-undef>, %stack.0
//
if (IsFill && SrcMO.getSubReg() == 0 && DstMO.isUndef()) {
const TargetRegisterClass *FillRC;
switch (DstMO.getSubReg()) {
default:
FillRC = nullptr;
break;
case AArch64::sub_32:
FillRC = &AArch64::GPR32RegClass;
break;
case AArch64::ssub:
FillRC = &AArch64::FPR32RegClass;
break;
case AArch64::dsub:
FillRC = &AArch64::FPR64RegClass;
break;
}
if (FillRC) {
assert(TRI.getRegSizeInBits(*getRegClass(SrcReg)) ==
TRI.getRegSizeInBits(*FillRC) &&
"Mismatched regclass size on folded subreg COPY");
loadRegFromStackSlot(MBB, InsertPt, DstReg, FrameIndex, FillRC, &TRI,
Register());
MachineInstr &LoadMI = *--InsertPt;
MachineOperand &LoadDst = LoadMI.getOperand(0);
assert(LoadDst.getSubReg() == 0 && "unexpected subreg on fill load");
LoadDst.setSubReg(DstMO.getSubReg());
LoadDst.setIsUndef();
return &LoadMI;
}
}
}
// Cannot fold.
return nullptr;
}
int llvm::isAArch64FrameOffsetLegal(const MachineInstr &MI,
StackOffset &SOffset,
bool *OutUseUnscaledOp,
unsigned *OutUnscaledOp,
int64_t *EmittableOffset) {
// Set output values in case of early exit.
if (EmittableOffset)
*EmittableOffset = 0;
if (OutUseUnscaledOp)
*OutUseUnscaledOp = false;
if (OutUnscaledOp)
*OutUnscaledOp = 0;
// Exit early for structured vector spills/fills as they can't take an
// immediate offset.
switch (MI.getOpcode()) {
default:
break;
case AArch64::LD1Rv1d:
case AArch64::LD1Rv2s:
case AArch64::LD1Rv2d:
case AArch64::LD1Rv4h:
case AArch64::LD1Rv4s:
case AArch64::LD1Rv8b:
case AArch64::LD1Rv8h:
case AArch64::LD1Rv16b:
case AArch64::LD1Twov2d:
case AArch64::LD1Threev2d:
case AArch64::LD1Fourv2d:
case AArch64::LD1Twov1d:
case AArch64::LD1Threev1d:
case AArch64::LD1Fourv1d:
case AArch64::ST1Twov2d:
case AArch64::ST1Threev2d:
case AArch64::ST1Fourv2d:
case AArch64::ST1Twov1d:
case AArch64::ST1Threev1d:
case AArch64::ST1Fourv1d:
case AArch64::ST1i8:
case AArch64::ST1i16:
case AArch64::ST1i32:
case AArch64::ST1i64:
case AArch64::IRG:
case AArch64::IRGstack:
case AArch64::STGloop:
case AArch64::STZGloop:
return AArch64FrameOffsetCannotUpdate;
}
// Get the min/max offset and the scale.
TypeSize ScaleValue(0U, false), Width(0U, false);
int64_t MinOff, MaxOff;
if (!AArch64InstrInfo::getMemOpInfo(MI.getOpcode(), ScaleValue, Width, MinOff,
MaxOff))
llvm_unreachable("unhandled opcode in isAArch64FrameOffsetLegal");
// Construct the complete offset.
bool IsMulVL = ScaleValue.isScalable();
unsigned Scale = ScaleValue.getKnownMinValue();
int64_t Offset = IsMulVL ? SOffset.getScalable() : SOffset.getFixed();
const MachineOperand &ImmOpnd =
MI.getOperand(AArch64InstrInfo::getLoadStoreImmIdx(MI.getOpcode()));
Offset += ImmOpnd.getImm() * Scale;
// If the offset doesn't match the scale, we rewrite the instruction to
// use the unscaled instruction instead. Likewise, if we have a negative
// offset and there is an unscaled op to use.
std::optional<unsigned> UnscaledOp =
AArch64InstrInfo::getUnscaledLdSt(MI.getOpcode());
bool useUnscaledOp = UnscaledOp && (Offset % Scale || Offset < 0);
if (useUnscaledOp &&
!AArch64InstrInfo::getMemOpInfo(*UnscaledOp, ScaleValue, Width, MinOff,
MaxOff))
llvm_unreachable("unhandled opcode in isAArch64FrameOffsetLegal");
Scale = ScaleValue.getKnownMinValue();
assert(IsMulVL == ScaleValue.isScalable() &&
"Unscaled opcode has different value for scalable");
int64_t Remainder = Offset % Scale;
assert(!(Remainder && useUnscaledOp) &&
"Cannot have remainder when using unscaled op");
assert(MinOff < MaxOff && "Unexpected Min/Max offsets");
int64_t NewOffset = Offset / Scale;
if (MinOff <= NewOffset && NewOffset <= MaxOff)
Offset = Remainder;
else {
NewOffset = NewOffset < 0 ? MinOff : MaxOff;
Offset = Offset - NewOffset * Scale;
}
if (EmittableOffset)
*EmittableOffset = NewOffset;
if (OutUseUnscaledOp)
*OutUseUnscaledOp = useUnscaledOp;
if (OutUnscaledOp && UnscaledOp)
*OutUnscaledOp = *UnscaledOp;
if (IsMulVL)
SOffset = StackOffset::get(SOffset.getFixed(), Offset);
else
SOffset = StackOffset::get(Offset, SOffset.getScalable());
return AArch64FrameOffsetCanUpdate |
(SOffset ? 0 : AArch64FrameOffsetIsLegal);
}
bool llvm::rewriteAArch64FrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
unsigned FrameReg, StackOffset &Offset,
const AArch64InstrInfo *TII) {
unsigned Opcode = MI.getOpcode();
unsigned ImmIdx = FrameRegIdx + 1;
if (Opcode == AArch64::ADDSXri || Opcode == AArch64::ADDXri) {
Offset += StackOffset::getFixed(MI.getOperand(ImmIdx).getImm());
emitFrameOffset(*MI.getParent(), MI, MI.getDebugLoc(),
MI.getOperand(0).getReg(), FrameReg, Offset, TII,
MachineInstr::NoFlags, (Opcode == AArch64::ADDSXri));
MI.eraseFromParent();
Offset = StackOffset();
return true;
}
int64_t NewOffset;
unsigned UnscaledOp;
bool UseUnscaledOp;
int Status = isAArch64FrameOffsetLegal(MI, Offset, &UseUnscaledOp,
&UnscaledOp, &NewOffset);
if (Status & AArch64FrameOffsetCanUpdate) {
if (Status & AArch64FrameOffsetIsLegal)
// Replace the FrameIndex with FrameReg.
MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
if (UseUnscaledOp)
MI.setDesc(TII->get(UnscaledOp));
MI.getOperand(ImmIdx).ChangeToImmediate(NewOffset);
return !Offset;
}
return false;
}
void AArch64InstrInfo::insertNoop(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI) const {
DebugLoc DL;
BuildMI(MBB, MI, DL, get(AArch64::HINT)).addImm(0);
}
MCInst AArch64InstrInfo::getNop() const {
return MCInstBuilder(AArch64::HINT).addImm(0);
}
// AArch64 supports MachineCombiner.
bool AArch64InstrInfo::useMachineCombiner() const { return true; }
// True when Opc sets flag
static bool isCombineInstrSettingFlag(unsigned Opc) {
switch (Opc) {
case AArch64::ADDSWrr:
case AArch64::ADDSWri:
case AArch64::ADDSXrr:
case AArch64::ADDSXri:
case AArch64::SUBSWrr:
case AArch64::SUBSXrr:
// Note: MSUB Wd,Wn,Wm,Wi -> Wd = Wi - WnxWm, not Wd=WnxWm - Wi.
case AArch64::SUBSWri:
case AArch64::SUBSXri:
return true;
default:
break;
}
return false;
}
// 32b Opcodes that can be combined with a MUL
static bool isCombineInstrCandidate32(unsigned Opc) {
switch (Opc) {
case AArch64::ADDWrr:
case AArch64::ADDWri:
case AArch64::SUBWrr:
case AArch64::ADDSWrr:
case AArch64::ADDSWri:
case AArch64::SUBSWrr:
// Note: MSUB Wd,Wn,Wm,Wi -> Wd = Wi - WnxWm, not Wd=WnxWm - Wi.
case AArch64::SUBWri:
case AArch64::SUBSWri:
return true;
default:
break;
}
return false;
}
// 64b Opcodes that can be combined with a MUL
static bool isCombineInstrCandidate64(unsigned Opc) {
switch (Opc) {
case AArch64::ADDXrr:
case AArch64::ADDXri:
case AArch64::SUBXrr:
case AArch64::ADDSXrr:
case AArch64::ADDSXri:
case AArch64::SUBSXrr:
// Note: MSUB Wd,Wn,Wm,Wi -> Wd = Wi - WnxWm, not Wd=WnxWm - Wi.
case AArch64::SUBXri:
case AArch64::SUBSXri:
case AArch64::ADDv8i8:
case AArch64::ADDv16i8:
case AArch64::ADDv4i16:
case AArch64::ADDv8i16:
case AArch64::ADDv2i32:
case AArch64::ADDv4i32:
case AArch64::SUBv8i8:
case AArch64::SUBv16i8:
case AArch64::SUBv4i16:
case AArch64::SUBv8i16:
case AArch64::SUBv2i32:
case AArch64::SUBv4i32:
return true;
default:
break;
}
return false;
}
// FP Opcodes that can be combined with a FMUL.
static bool isCombineInstrCandidateFP(const MachineInstr &Inst) {
switch (Inst.getOpcode()) {
default:
break;
case AArch64::FADDHrr:
case AArch64::FADDSrr:
case AArch64::FADDDrr:
case AArch64::FADDv4f16:
case AArch64::FADDv8f16:
case AArch64::FADDv2f32:
case AArch64::FADDv2f64:
case AArch64::FADDv4f32:
case AArch64::FSUBHrr:
case AArch64::FSUBSrr:
case AArch64::FSUBDrr:
case AArch64::FSUBv4f16:
case AArch64::FSUBv8f16:
case AArch64::FSUBv2f32:
case AArch64::FSUBv2f64:
case AArch64::FSUBv4f32:
TargetOptions Options = Inst.getParent()->getParent()->getTarget().Options;
// We can fuse FADD/FSUB with FMUL, if fusion is either allowed globally by
// the target options or if FADD/FSUB has the contract fast-math flag.
return Options.UnsafeFPMath ||
Options.AllowFPOpFusion == FPOpFusion::Fast ||
Inst.getFlag(MachineInstr::FmContract);
return true;
}
return false;
}
// Opcodes that can be combined with a MUL
static bool isCombineInstrCandidate(unsigned Opc) {
return (isCombineInstrCandidate32(Opc) || isCombineInstrCandidate64(Opc));
}
//
// Utility routine that checks if \param MO is defined by an
// \param CombineOpc instruction in the basic block \param MBB
static bool canCombine(MachineBasicBlock &MBB, MachineOperand &MO,
unsigned CombineOpc, unsigned ZeroReg = 0,
bool CheckZeroReg = false) {
MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
MachineInstr *MI = nullptr;
if (MO.isReg() && MO.getReg().isVirtual())
MI = MRI.getUniqueVRegDef(MO.getReg());
// And it needs to be in the trace (otherwise, it won't have a depth).
if (!MI || MI->getParent() != &MBB || (unsigned)MI->getOpcode() != CombineOpc)
return false;
// Must only used by the user we combine with.
if (!MRI.hasOneNonDBGUse(MI->getOperand(0).getReg()))
return false;
if (CheckZeroReg) {
assert(MI->getNumOperands() >= 4 && MI->getOperand(0).isReg() &&
MI->getOperand(1).isReg() && MI->getOperand(2).isReg() &&
MI->getOperand(3).isReg() && "MAdd/MSub must have a least 4 regs");
// The third input reg must be zero.
if (MI->getOperand(3).getReg() != ZeroReg)
return false;
}
if (isCombineInstrSettingFlag(CombineOpc) &&
MI->findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr, true) == -1)
return false;
return true;
}
//
// Is \param MO defined by an integer multiply and can be combined?
static bool canCombineWithMUL(MachineBasicBlock &MBB, MachineOperand &MO,
unsigned MulOpc, unsigned ZeroReg) {
return canCombine(MBB, MO, MulOpc, ZeroReg, true);
}
//
// Is \param MO defined by a floating-point multiply and can be combined?
static bool canCombineWithFMUL(MachineBasicBlock &MBB, MachineOperand &MO,
unsigned MulOpc) {
return canCombine(MBB, MO, MulOpc);
}
// TODO: There are many more machine instruction opcodes to match:
// 1. Other data types (integer, vectors)
// 2. Other math / logic operations (xor, or)
// 3. Other forms of the same operation (intrinsics and other variants)
bool AArch64InstrInfo::isAssociativeAndCommutative(const MachineInstr &Inst,
bool Invert) const {
if (Invert)
return false;
switch (Inst.getOpcode()) {
// == Floating-point types ==
// -- Floating-point instructions --
case AArch64::FADDHrr:
case AArch64::FADDSrr:
case AArch64::FADDDrr:
case AArch64::FMULHrr:
case AArch64::FMULSrr:
case AArch64::FMULDrr:
case AArch64::FMULX16:
case AArch64::FMULX32:
case AArch64::FMULX64:
// -- Advanced SIMD instructions --
case AArch64::FADDv4f16:
case AArch64::FADDv8f16:
case AArch64::FADDv2f32:
case AArch64::FADDv4f32:
case AArch64::FADDv2f64:
case AArch64::FMULv4f16:
case AArch64::FMULv8f16:
case AArch64::FMULv2f32:
case AArch64::FMULv4f32:
case AArch64::FMULv2f64:
case AArch64::FMULXv4f16:
case AArch64::FMULXv8f16:
case AArch64::FMULXv2f32:
case AArch64::FMULXv4f32:
case AArch64::FMULXv2f64:
// -- SVE instructions --
// Opcodes FMULX_ZZZ_? don't exist because there is no unpredicated FMULX
// in the SVE instruction set (though there are predicated ones).
case AArch64::FADD_ZZZ_H:
case AArch64::FADD_ZZZ_S:
case AArch64::FADD_ZZZ_D:
case AArch64::FMUL_ZZZ_H:
case AArch64::FMUL_ZZZ_S:
case AArch64::FMUL_ZZZ_D:
return Inst.getParent()->getParent()->getTarget().Options.UnsafeFPMath ||
(Inst.getFlag(MachineInstr::MIFlag::FmReassoc) &&
Inst.getFlag(MachineInstr::MIFlag::FmNsz));
// == Integer types ==
// -- Base instructions --
// Opcodes MULWrr and MULXrr don't exist because
// `MUL <Wd>, <Wn>, <Wm>` and `MUL <Xd>, <Xn>, <Xm>` are aliases of
// `MADD <Wd>, <Wn>, <Wm>, WZR` and `MADD <Xd>, <Xn>, <Xm>, XZR` respectively.
// The machine-combiner does not support three-source-operands machine
// instruction. So we cannot reassociate MULs.
case AArch64::ADDWrr:
case AArch64::ADDXrr:
case AArch64::ANDWrr:
case AArch64::ANDXrr:
case AArch64::ORRWrr:
case AArch64::ORRXrr:
case AArch64::EORWrr:
case AArch64::EORXrr:
case AArch64::EONWrr:
case AArch64::EONXrr:
// -- Advanced SIMD instructions --
// Opcodes MULv1i64 and MULv2i64 don't exist because there is no 64-bit MUL
// in the Advanced SIMD instruction set.
case AArch64::ADDv8i8:
case AArch64::ADDv16i8:
case AArch64::ADDv4i16:
case AArch64::ADDv8i16:
case AArch64::ADDv2i32:
case AArch64::ADDv4i32:
case AArch64::ADDv1i64:
case AArch64::ADDv2i64:
case AArch64::MULv8i8:
case AArch64::MULv16i8:
case AArch64::MULv4i16:
case AArch64::MULv8i16:
case AArch64::MULv2i32:
case AArch64::MULv4i32:
case AArch64::ANDv8i8:
case AArch64::ANDv16i8:
case AArch64::ORRv8i8:
case AArch64::ORRv16i8:
case AArch64::EORv8i8:
case AArch64::EORv16i8:
// -- SVE instructions --
case AArch64::ADD_ZZZ_B:
case AArch64::ADD_ZZZ_H:
case AArch64::ADD_ZZZ_S:
case AArch64::ADD_ZZZ_D:
case AArch64::MUL_ZZZ_B:
case AArch64::MUL_ZZZ_H:
case AArch64::MUL_ZZZ_S:
case AArch64::MUL_ZZZ_D:
case AArch64::AND_ZZZ:
case AArch64::ORR_ZZZ:
case AArch64::EOR_ZZZ:
return true;
default:
return false;
}
}
/// Find instructions that can be turned into madd.
static bool getMaddPatterns(MachineInstr &Root,
SmallVectorImpl<unsigned> &Patterns) {
unsigned Opc = Root.getOpcode();
MachineBasicBlock &MBB = *Root.getParent();
bool Found = false;
if (!isCombineInstrCandidate(Opc))
return false;
if (isCombineInstrSettingFlag(Opc)) {
int Cmp_NZCV =
Root.findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr, true);
// When NZCV is live bail out.
if (Cmp_NZCV == -1)
return false;
unsigned NewOpc = convertToNonFlagSettingOpc(Root);
// When opcode can't change bail out.
// CHECKME: do we miss any cases for opcode conversion?
if (NewOpc == Opc)
return false;
Opc = NewOpc;
}
auto setFound = [&](int Opcode, int Operand, unsigned ZeroReg,
unsigned Pattern) {
if (canCombineWithMUL(MBB, Root.getOperand(Operand), Opcode, ZeroReg)) {
Patterns.push_back(Pattern);
Found = true;
}
};
auto setVFound = [&](int Opcode, int Operand, unsigned Pattern) {
if (canCombine(MBB, Root.getOperand(Operand), Opcode)) {
Patterns.push_back(Pattern);
Found = true;
}
};
typedef AArch64MachineCombinerPattern MCP;
switch (Opc) {
default:
break;
case AArch64::ADDWrr:
assert(Root.getOperand(1).isReg() && Root.getOperand(2).isReg() &&
"ADDWrr does not have register operands");
setFound(AArch64::MADDWrrr, 1, AArch64::WZR, MCP::MULADDW_OP1);
setFound(AArch64::MADDWrrr, 2, AArch64::WZR, MCP::MULADDW_OP2);
break;
case AArch64::ADDXrr:
setFound(AArch64::MADDXrrr, 1, AArch64::XZR, MCP::MULADDX_OP1);
setFound(AArch64::MADDXrrr, 2, AArch64::XZR, MCP::MULADDX_OP2);
break;
case AArch64::SUBWrr:
setFound(AArch64::MADDWrrr, 2, AArch64::WZR, MCP::MULSUBW_OP2);
setFound(AArch64::MADDWrrr, 1, AArch64::WZR, MCP::MULSUBW_OP1);
break;
case AArch64::SUBXrr:
setFound(AArch64::MADDXrrr, 2, AArch64::XZR, MCP::MULSUBX_OP2);
setFound(AArch64::MADDXrrr, 1, AArch64::XZR, MCP::MULSUBX_OP1);
break;
case AArch64::ADDWri:
setFound(AArch64::MADDWrrr, 1, AArch64::WZR, MCP::MULADDWI_OP1);
break;
case AArch64::ADDXri:
setFound(AArch64::MADDXrrr, 1, AArch64::XZR, MCP::MULADDXI_OP1);
break;
case AArch64::SUBWri:
setFound(AArch64::MADDWrrr, 1, AArch64::WZR, MCP::MULSUBWI_OP1);
break;
case AArch64::SUBXri:
setFound(AArch64::MADDXrrr, 1, AArch64::XZR, MCP::MULSUBXI_OP1);
break;
case AArch64::ADDv8i8:
setVFound(AArch64::MULv8i8, 1, MCP::MULADDv8i8_OP1);
setVFound(AArch64::MULv8i8, 2, MCP::MULADDv8i8_OP2);
break;
case AArch64::ADDv16i8:
setVFound(AArch64::MULv16i8, 1, MCP::MULADDv16i8_OP1);
setVFound(AArch64::MULv16i8, 2, MCP::MULADDv16i8_OP2);
break;
case AArch64::ADDv4i16:
setVFound(AArch64::MULv4i16, 1, MCP::MULADDv4i16_OP1);
setVFound(AArch64::MULv4i16, 2, MCP::MULADDv4i16_OP2);
setVFound(AArch64::MULv4i16_indexed, 1, MCP::MULADDv4i16_indexed_OP1);
setVFound(AArch64::MULv4i16_indexed, 2, MCP::MULADDv4i16_indexed_OP2);
break;
case AArch64::ADDv8i16:
setVFound(AArch64::MULv8i16, 1, MCP::MULADDv8i16_OP1);
setVFound(AArch64::MULv8i16, 2, MCP::MULADDv8i16_OP2);
setVFound(AArch64::MULv8i16_indexed, 1, MCP::MULADDv8i16_indexed_OP1);
setVFound(AArch64::MULv8i16_indexed, 2, MCP::MULADDv8i16_indexed_OP2);
break;
case AArch64::ADDv2i32:
setVFound(AArch64::MULv2i32, 1, MCP::MULADDv2i32_OP1);
setVFound(AArch64::MULv2i32, 2, MCP::MULADDv2i32_OP2);
setVFound(AArch64::MULv2i32_indexed, 1, MCP::MULADDv2i32_indexed_OP1);
setVFound(AArch64::MULv2i32_indexed, 2, MCP::MULADDv2i32_indexed_OP2);
break;
case AArch64::ADDv4i32:
setVFound(AArch64::MULv4i32, 1, MCP::MULADDv4i32_OP1);
setVFound(AArch64::MULv4i32, 2, MCP::MULADDv4i32_OP2);
setVFound(AArch64::MULv4i32_indexed, 1, MCP::MULADDv4i32_indexed_OP1);
setVFound(AArch64::MULv4i32_indexed, 2, MCP::MULADDv4i32_indexed_OP2);
break;
case AArch64::SUBv8i8:
setVFound(AArch64::MULv8i8, 1, MCP::MULSUBv8i8_OP1);
setVFound(AArch64::MULv8i8, 2, MCP::MULSUBv8i8_OP2);
break;
case AArch64::SUBv16i8:
setVFound(AArch64::MULv16i8, 1, MCP::MULSUBv16i8_OP1);
setVFound(AArch64::MULv16i8, 2, MCP::MULSUBv16i8_OP2);
break;
case AArch64::SUBv4i16:
setVFound(AArch64::MULv4i16, 1, MCP::MULSUBv4i16_OP1);
setVFound(AArch64::MULv4i16, 2, MCP::MULSUBv4i16_OP2);
setVFound(AArch64::MULv4i16_indexed, 1, MCP::MULSUBv4i16_indexed_OP1);
setVFound(AArch64::MULv4i16_indexed, 2, MCP::MULSUBv4i16_indexed_OP2);
break;
case AArch64::SUBv8i16:
setVFound(AArch64::MULv8i16, 1, MCP::MULSUBv8i16_OP1);
setVFound(AArch64::MULv8i16, 2, MCP::MULSUBv8i16_OP2);
setVFound(AArch64::MULv8i16_indexed, 1, MCP::MULSUBv8i16_indexed_OP1);
setVFound(AArch64::MULv8i16_indexed, 2, MCP::MULSUBv8i16_indexed_OP2);
break;
case AArch64::SUBv2i32:
setVFound(AArch64::MULv2i32, 1, MCP::MULSUBv2i32_OP1);
setVFound(AArch64::MULv2i32, 2, MCP::MULSUBv2i32_OP2);
setVFound(AArch64::MULv2i32_indexed, 1, MCP::MULSUBv2i32_indexed_OP1);
setVFound(AArch64::MULv2i32_indexed, 2, MCP::MULSUBv2i32_indexed_OP2);
break;
case AArch64::SUBv4i32:
setVFound(AArch64::MULv4i32, 1, MCP::MULSUBv4i32_OP1);
setVFound(AArch64::MULv4i32, 2, MCP::MULSUBv4i32_OP2);
setVFound(AArch64::MULv4i32_indexed, 1, MCP::MULSUBv4i32_indexed_OP1);
setVFound(AArch64::MULv4i32_indexed, 2, MCP::MULSUBv4i32_indexed_OP2);
break;
}
return Found;
}
/// Floating-Point Support
/// Find instructions that can be turned into madd.
static bool getFMAPatterns(MachineInstr &Root,
SmallVectorImpl<unsigned> &Patterns) {
if (!isCombineInstrCandidateFP(Root))
return false;
MachineBasicBlock &MBB = *Root.getParent();
bool Found = false;
auto Match = [&](int Opcode, int Operand, unsigned Pattern) -> bool {
if (canCombineWithFMUL(MBB, Root.getOperand(Operand), Opcode)) {
Patterns.push_back(Pattern);
return true;
}
return false;
};
typedef AArch64MachineCombinerPattern MCP;
switch (Root.getOpcode()) {
default:
assert(false && "Unsupported FP instruction in combiner\n");
break;
case AArch64::FADDHrr:
assert(Root.getOperand(1).isReg() && Root.getOperand(2).isReg() &&
"FADDHrr does not have register operands");
Found = Match(AArch64::FMULHrr, 1, MCP::FMULADDH_OP1);
Found |= Match(AArch64::FMULHrr, 2, MCP::FMULADDH_OP2);
break;
case AArch64::FADDSrr:
assert(Root.getOperand(1).isReg() && Root.getOperand(2).isReg() &&
"FADDSrr does not have register operands");
Found |= Match(AArch64::FMULSrr, 1, MCP::FMULADDS_OP1) ||
Match(AArch64::FMULv1i32_indexed, 1, MCP::FMLAv1i32_indexed_OP1);
Found |= Match(AArch64::FMULSrr, 2, MCP::FMULADDS_OP2) ||
Match(AArch64::FMULv1i32_indexed, 2, MCP::FMLAv1i32_indexed_OP2);
break;
case AArch64::FADDDrr:
Found |= Match(AArch64::FMULDrr, 1, MCP::FMULADDD_OP1) ||
Match(AArch64::FMULv1i64_indexed, 1, MCP::FMLAv1i64_indexed_OP1);
Found |= Match(AArch64::FMULDrr, 2, MCP::FMULADDD_OP2) ||
Match(AArch64::FMULv1i64_indexed, 2, MCP::FMLAv1i64_indexed_OP2);
break;
case AArch64::FADDv4f16:
Found |= Match(AArch64::FMULv4i16_indexed, 1, MCP::FMLAv4i16_indexed_OP1) ||
Match(AArch64::FMULv4f16, 1, MCP::FMLAv4f16_OP1);
Found |= Match(AArch64::FMULv4i16_indexed, 2, MCP::FMLAv4i16_indexed_OP2) ||
Match(AArch64::FMULv4f16, 2, MCP::FMLAv4f16_OP2);
break;
case AArch64::FADDv8f16:
Found |= Match(AArch64::FMULv8i16_indexed, 1, MCP::FMLAv8i16_indexed_OP1) ||
Match(AArch64::FMULv8f16, 1, MCP::FMLAv8f16_OP1);
Found |= Match(AArch64::FMULv8i16_indexed, 2, MCP::FMLAv8i16_indexed_OP2) ||
Match(AArch64::FMULv8f16, 2, MCP::FMLAv8f16_OP2);
break;
case AArch64::FADDv2f32:
Found |= Match(AArch64::FMULv2i32_indexed, 1, MCP::FMLAv2i32_indexed_OP1) ||
Match(AArch64::FMULv2f32, 1, MCP::FMLAv2f32_OP1);
Found |= Match(AArch64::FMULv2i32_indexed, 2, MCP::FMLAv2i32_indexed_OP2) ||
Match(AArch64::FMULv2f32, 2, MCP::FMLAv2f32_OP2);
break;
case AArch64::FADDv2f64:
Found |= Match(AArch64::FMULv2i64_indexed, 1, MCP::FMLAv2i64_indexed_OP1) ||
Match(AArch64::FMULv2f64, 1, MCP::FMLAv2f64_OP1);
Found |= Match(AArch64::FMULv2i64_indexed, 2, MCP::FMLAv2i64_indexed_OP2) ||
Match(AArch64::FMULv2f64, 2, MCP::FMLAv2f64_OP2);
break;
case AArch64::FADDv4f32:
Found |= Match(AArch64::FMULv4i32_indexed, 1, MCP::FMLAv4i32_indexed_OP1) ||
Match(AArch64::FMULv4f32, 1, MCP::FMLAv4f32_OP1);
Found |= Match(AArch64::FMULv4i32_indexed, 2, MCP::FMLAv4i32_indexed_OP2) ||
Match(AArch64::FMULv4f32, 2, MCP::FMLAv4f32_OP2);
break;
case AArch64::FSUBHrr:
Found = Match(AArch64::FMULHrr, 1, MCP::FMULSUBH_OP1);
Found |= Match(AArch64::FMULHrr, 2, MCP::FMULSUBH_OP2);
Found |= Match(AArch64::FNMULHrr, 1, MCP::FNMULSUBH_OP1);
break;
case AArch64::FSUBSrr:
Found = Match(AArch64::FMULSrr, 1, MCP::FMULSUBS_OP1);
Found |= Match(AArch64::FMULSrr, 2, MCP::FMULSUBS_OP2) ||
Match(AArch64::FMULv1i32_indexed, 2, MCP::FMLSv1i32_indexed_OP2);
Found |= Match(AArch64::FNMULSrr, 1, MCP::FNMULSUBS_OP1);
break;
case AArch64::FSUBDrr:
Found = Match(AArch64::FMULDrr, 1, MCP::FMULSUBD_OP1);
Found |= Match(AArch64::FMULDrr, 2, MCP::FMULSUBD_OP2) ||
Match(AArch64::FMULv1i64_indexed, 2, MCP::FMLSv1i64_indexed_OP2);
Found |= Match(AArch64::FNMULDrr, 1, MCP::FNMULSUBD_OP1);
break;
case AArch64::FSUBv4f16:
Found |= Match(AArch64::FMULv4i16_indexed, 2, MCP::FMLSv4i16_indexed_OP2) ||
Match(AArch64::FMULv4f16, 2, MCP::FMLSv4f16_OP2);
Found |= Match(AArch64::FMULv4i16_indexed, 1, MCP::FMLSv4i16_indexed_OP1) ||
Match(AArch64::FMULv4f16, 1, MCP::FMLSv4f16_OP1);
break;
case AArch64::FSUBv8f16:
Found |= Match(AArch64::FMULv8i16_indexed, 2, MCP::FMLSv8i16_indexed_OP2) ||
Match(AArch64::FMULv8f16, 2, MCP::FMLSv8f16_OP2);
Found |= Match(AArch64::FMULv8i16_indexed, 1, MCP::FMLSv8i16_indexed_OP1) ||
Match(AArch64::FMULv8f16, 1, MCP::FMLSv8f16_OP1);
break;
case AArch64::FSUBv2f32:
Found |= Match(AArch64::FMULv2i32_indexed, 2, MCP::FMLSv2i32_indexed_OP2) ||
Match(AArch64::FMULv2f32, 2, MCP::FMLSv2f32_OP2);
Found |= Match(AArch64::FMULv2i32_indexed, 1, MCP::FMLSv2i32_indexed_OP1) ||
Match(AArch64::FMULv2f32, 1, MCP::FMLSv2f32_OP1);
break;
case AArch64::FSUBv2f64:
Found |= Match(AArch64::FMULv2i64_indexed, 2, MCP::FMLSv2i64_indexed_OP2) ||
Match(AArch64::FMULv2f64, 2, MCP::FMLSv2f64_OP2);
Found |= Match(AArch64::FMULv2i64_indexed, 1, MCP::FMLSv2i64_indexed_OP1) ||
Match(AArch64::FMULv2f64, 1, MCP::FMLSv2f64_OP1);
break;
case AArch64::FSUBv4f32:
Found |= Match(AArch64::FMULv4i32_indexed, 2, MCP::FMLSv4i32_indexed_OP2) ||
Match(AArch64::FMULv4f32, 2, MCP::FMLSv4f32_OP2);
Found |= Match(AArch64::FMULv4i32_indexed, 1, MCP::FMLSv4i32_indexed_OP1) ||
Match(AArch64::FMULv4f32, 1, MCP::FMLSv4f32_OP1);
break;
}
return Found;
}
static bool getFMULPatterns(MachineInstr &Root,
SmallVectorImpl<unsigned> &Patterns) {
MachineBasicBlock &MBB = *Root.getParent();
bool Found = false;
auto Match = [&](unsigned Opcode, int Operand, unsigned Pattern) -> bool {
MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
MachineOperand &MO = Root.getOperand(Operand);
MachineInstr *MI = nullptr;
if (MO.isReg() && MO.getReg().isVirtual())
MI = MRI.getUniqueVRegDef(MO.getReg());
// Ignore No-op COPYs in FMUL(COPY(DUP(..)))
if (MI && MI->getOpcode() == TargetOpcode::COPY &&
MI->getOperand(1).getReg().isVirtual())
MI = MRI.getUniqueVRegDef(MI->getOperand(1).getReg());
if (MI && MI->getOpcode() == Opcode) {
Patterns.push_back(Pattern);
return true;
}
return false;
};
typedef AArch64MachineCombinerPattern MCP;
switch (Root.getOpcode()) {
default:
return false;
case AArch64::FMULv2f32:
Found = Match(AArch64::DUPv2i32lane, 1, MCP::FMULv2i32_indexed_OP1);
Found |= Match(AArch64::DUPv2i32lane, 2, MCP::FMULv2i32_indexed_OP2);
break;
case AArch64::FMULv2f64:
Found = Match(AArch64::DUPv2i64lane, 1, MCP::FMULv2i64_indexed_OP1);
Found |= Match(AArch64::DUPv2i64lane, 2, MCP::FMULv2i64_indexed_OP2);
break;
case AArch64::FMULv4f16:
Found = Match(AArch64::DUPv4i16lane, 1, MCP::FMULv4i16_indexed_OP1);
Found |= Match(AArch64::DUPv4i16lane, 2, MCP::FMULv4i16_indexed_OP2);
break;
case AArch64::FMULv4f32:
Found = Match(AArch64::DUPv4i32lane, 1, MCP::FMULv4i32_indexed_OP1);
Found |= Match(AArch64::DUPv4i32lane, 2, MCP::FMULv4i32_indexed_OP2);
break;
case AArch64::FMULv8f16:
Found = Match(AArch64::DUPv8i16lane, 1, MCP::FMULv8i16_indexed_OP1);
Found |= Match(AArch64::DUPv8i16lane, 2, MCP::FMULv8i16_indexed_OP2);
break;
}
return Found;
}
static bool getFNEGPatterns(MachineInstr &Root,
SmallVectorImpl<unsigned> &Patterns) {
unsigned Opc = Root.getOpcode();
MachineBasicBlock &MBB = *Root.getParent();
MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
auto Match = [&](unsigned Opcode, unsigned Pattern) -> bool {
MachineOperand &MO = Root.getOperand(1);
MachineInstr *MI = MRI.getUniqueVRegDef(MO.getReg());
if (MI != nullptr && (MI->getOpcode() == Opcode) &&
MRI.hasOneNonDBGUse(MI->getOperand(0).getReg()) &&
Root.getFlag(MachineInstr::MIFlag::FmContract) &&
Root.getFlag(MachineInstr::MIFlag::FmNsz) &&
MI->getFlag(MachineInstr::MIFlag::FmContract) &&
MI->getFlag(MachineInstr::MIFlag::FmNsz)) {
Patterns.push_back(Pattern);
return true;
}
return false;
};
switch (Opc) {
default:
break;
case AArch64::FNEGDr:
return Match(AArch64::FMADDDrrr, AArch64MachineCombinerPattern::FNMADD);
case AArch64::FNEGSr:
return Match(AArch64::FMADDSrrr, AArch64MachineCombinerPattern::FNMADD);
}
return false;
}
/// Return true when a code sequence can improve throughput. It
/// should be called only for instructions in loops.
/// \param Pattern - combiner pattern
bool AArch64InstrInfo::isThroughputPattern(unsigned Pattern) const {
switch (Pattern) {
default:
break;
case AArch64MachineCombinerPattern::FMULADDH_OP1:
case AArch64MachineCombinerPattern::FMULADDH_OP2:
case AArch64MachineCombinerPattern::FMULSUBH_OP1:
case AArch64MachineCombinerPattern::FMULSUBH_OP2:
case AArch64MachineCombinerPattern::FMULADDS_OP1:
case AArch64MachineCombinerPattern::FMULADDS_OP2:
case AArch64MachineCombinerPattern::FMULSUBS_OP1:
case AArch64MachineCombinerPattern::FMULSUBS_OP2:
case AArch64MachineCombinerPattern::FMULADDD_OP1:
case AArch64MachineCombinerPattern::FMULADDD_OP2:
case AArch64MachineCombinerPattern::FMULSUBD_OP1:
case AArch64MachineCombinerPattern::FMULSUBD_OP2:
case AArch64MachineCombinerPattern::FNMULSUBH_OP1:
case AArch64MachineCombinerPattern::FNMULSUBS_OP1:
case AArch64MachineCombinerPattern::FNMULSUBD_OP1:
case AArch64MachineCombinerPattern::FMLAv4i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv4i16_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv8i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv8i16_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv1i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv1i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv1i64_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv1i64_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv4f16_OP2:
case AArch64MachineCombinerPattern::FMLAv4f16_OP1:
case AArch64MachineCombinerPattern::FMLAv8f16_OP1:
case AArch64MachineCombinerPattern::FMLAv8f16_OP2:
case AArch64MachineCombinerPattern::FMLAv2f32_OP2:
case AArch64MachineCombinerPattern::FMLAv2f32_OP1:
case AArch64MachineCombinerPattern::FMLAv2f64_OP1:
case AArch64MachineCombinerPattern::FMLAv2f64_OP2:
case AArch64MachineCombinerPattern::FMLAv2i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv2i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv2i64_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv2i64_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv4f32_OP1:
case AArch64MachineCombinerPattern::FMLAv4f32_OP2:
case AArch64MachineCombinerPattern::FMLAv4i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv4i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv4i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMLSv4i16_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv8i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMLSv8i16_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv1i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv1i64_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv2i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv2i64_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv4f16_OP1:
case AArch64MachineCombinerPattern::FMLSv4f16_OP2:
case AArch64MachineCombinerPattern::FMLSv8f16_OP1:
case AArch64MachineCombinerPattern::FMLSv8f16_OP2:
case AArch64MachineCombinerPattern::FMLSv2f32_OP2:
case AArch64MachineCombinerPattern::FMLSv2f64_OP2:
case AArch64MachineCombinerPattern::FMLSv4i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLSv4f32_OP2:
case AArch64MachineCombinerPattern::FMULv2i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv2i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMULv2i64_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv2i64_indexed_OP2:
case AArch64MachineCombinerPattern::FMULv4i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv4i16_indexed_OP2:
case AArch64MachineCombinerPattern::FMULv4i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv4i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMULv8i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv8i16_indexed_OP2:
case AArch64MachineCombinerPattern::MULADDv8i8_OP1:
case AArch64MachineCombinerPattern::MULADDv8i8_OP2:
case AArch64MachineCombinerPattern::MULADDv16i8_OP1:
case AArch64MachineCombinerPattern::MULADDv16i8_OP2:
case AArch64MachineCombinerPattern::MULADDv4i16_OP1:
case AArch64MachineCombinerPattern::MULADDv4i16_OP2:
case AArch64MachineCombinerPattern::MULADDv8i16_OP1:
case AArch64MachineCombinerPattern::MULADDv8i16_OP2:
case AArch64MachineCombinerPattern::MULADDv2i32_OP1:
case AArch64MachineCombinerPattern::MULADDv2i32_OP2:
case AArch64MachineCombinerPattern::MULADDv4i32_OP1:
case AArch64MachineCombinerPattern::MULADDv4i32_OP2:
case AArch64MachineCombinerPattern::MULSUBv8i8_OP1:
case AArch64MachineCombinerPattern::MULSUBv8i8_OP2:
case AArch64MachineCombinerPattern::MULSUBv16i8_OP1:
case AArch64MachineCombinerPattern::MULSUBv16i8_OP2:
case AArch64MachineCombinerPattern::MULSUBv4i16_OP1:
case AArch64MachineCombinerPattern::MULSUBv4i16_OP2:
case AArch64MachineCombinerPattern::MULSUBv8i16_OP1:
case AArch64MachineCombinerPattern::MULSUBv8i16_OP2:
case AArch64MachineCombinerPattern::MULSUBv2i32_OP1:
case AArch64MachineCombinerPattern::MULSUBv2i32_OP2:
case AArch64MachineCombinerPattern::MULSUBv4i32_OP1:
case AArch64MachineCombinerPattern::MULSUBv4i32_OP2:
case AArch64MachineCombinerPattern::MULADDv4i16_indexed_OP1:
case AArch64MachineCombinerPattern::MULADDv4i16_indexed_OP2:
case AArch64MachineCombinerPattern::MULADDv8i16_indexed_OP1:
case AArch64MachineCombinerPattern::MULADDv8i16_indexed_OP2:
case AArch64MachineCombinerPattern::MULADDv2i32_indexed_OP1:
case AArch64MachineCombinerPattern::MULADDv2i32_indexed_OP2:
case AArch64MachineCombinerPattern::MULADDv4i32_indexed_OP1:
case AArch64MachineCombinerPattern::MULADDv4i32_indexed_OP2:
case AArch64MachineCombinerPattern::MULSUBv4i16_indexed_OP1:
case AArch64MachineCombinerPattern::MULSUBv4i16_indexed_OP2:
case AArch64MachineCombinerPattern::MULSUBv8i16_indexed_OP1:
case AArch64MachineCombinerPattern::MULSUBv8i16_indexed_OP2:
case AArch64MachineCombinerPattern::MULSUBv2i32_indexed_OP1:
case AArch64MachineCombinerPattern::MULSUBv2i32_indexed_OP2:
case AArch64MachineCombinerPattern::MULSUBv4i32_indexed_OP1:
case AArch64MachineCombinerPattern::MULSUBv4i32_indexed_OP2:
return true;
} // end switch (Pattern)
return false;
}
/// Find other MI combine patterns.
static bool getMiscPatterns(MachineInstr &Root,
SmallVectorImpl<unsigned> &Patterns) {
// A - (B + C) ==> (A - B) - C or (A - C) - B
unsigned Opc = Root.getOpcode();
MachineBasicBlock &MBB = *Root.getParent();
switch (Opc) {
case AArch64::SUBWrr:
case AArch64::SUBSWrr:
case AArch64::SUBXrr:
case AArch64::SUBSXrr:
// Found candidate root.
break;
default:
return false;
}
if (isCombineInstrSettingFlag(Opc) &&
Root.findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr, true) ==
-1)
return false;
if (canCombine(MBB, Root.getOperand(2), AArch64::ADDWrr) ||
canCombine(MBB, Root.getOperand(2), AArch64::ADDSWrr) ||
canCombine(MBB, Root.getOperand(2), AArch64::ADDXrr) ||
canCombine(MBB, Root.getOperand(2), AArch64::ADDSXrr)) {
Patterns.push_back(AArch64MachineCombinerPattern::SUBADD_OP1);
Patterns.push_back(AArch64MachineCombinerPattern::SUBADD_OP2);
return true;
}
return false;
}
CombinerObjective
AArch64InstrInfo::getCombinerObjective(unsigned Pattern) const {
switch (Pattern) {
case AArch64MachineCombinerPattern::SUBADD_OP1:
case AArch64MachineCombinerPattern::SUBADD_OP2:
return CombinerObjective::MustReduceDepth;
default:
return TargetInstrInfo::getCombinerObjective(Pattern);
}
}
/// Return true when there is potentially a faster code sequence for an
/// instruction chain ending in \p Root. All potential patterns are listed in
/// the \p Pattern vector. Pattern should be sorted in priority order since the
/// pattern evaluator stops checking as soon as it finds a faster sequence.
bool AArch64InstrInfo::getMachineCombinerPatterns(
MachineInstr &Root, SmallVectorImpl<unsigned> &Patterns,
bool DoRegPressureReduce) const {
// Integer patterns
if (getMaddPatterns(Root, Patterns))
return true;
// Floating point patterns
if (getFMULPatterns(Root, Patterns))
return true;
if (getFMAPatterns(Root, Patterns))
return true;
if (getFNEGPatterns(Root, Patterns))
return true;
// Other patterns
if (getMiscPatterns(Root, Patterns))
return true;
return TargetInstrInfo::getMachineCombinerPatterns(Root, Patterns,
DoRegPressureReduce);
}
enum class FMAInstKind { Default, Indexed, Accumulator };
/// genFusedMultiply - Generate fused multiply instructions.
/// This function supports both integer and floating point instructions.
/// A typical example:
/// F|MUL I=A,B,0
/// F|ADD R,I,C
/// ==> F|MADD R,A,B,C
/// \param MF Containing MachineFunction
/// \param MRI Register information
/// \param TII Target information
/// \param Root is the F|ADD instruction
/// \param [out] InsInstrs is a vector of machine instructions and will
/// contain the generated madd instruction
/// \param IdxMulOpd is index of operand in Root that is the result of
/// the F|MUL. In the example above IdxMulOpd is 1.
/// \param MaddOpc the opcode fo the f|madd instruction
/// \param RC Register class of operands
/// \param kind of fma instruction (addressing mode) to be generated
/// \param ReplacedAddend is the result register from the instruction
/// replacing the non-combined operand, if any.
static MachineInstr *
genFusedMultiply(MachineFunction &MF, MachineRegisterInfo &MRI,
const TargetInstrInfo *TII, MachineInstr &Root,
SmallVectorImpl<MachineInstr *> &InsInstrs, unsigned IdxMulOpd,
unsigned MaddOpc, const TargetRegisterClass *RC,
FMAInstKind kind = FMAInstKind::Default,
const Register *ReplacedAddend = nullptr) {
assert(IdxMulOpd == 1 || IdxMulOpd == 2);
unsigned IdxOtherOpd = IdxMulOpd == 1 ? 2 : 1;
MachineInstr *MUL = MRI.getUniqueVRegDef(Root.getOperand(IdxMulOpd).getReg());
Register ResultReg = Root.getOperand(0).getReg();
Register SrcReg0 = MUL->getOperand(1).getReg();
bool Src0IsKill = MUL->getOperand(1).isKill();
Register SrcReg1 = MUL->getOperand(2).getReg();
bool Src1IsKill = MUL->getOperand(2).isKill();
Register SrcReg2;
bool Src2IsKill;
if (ReplacedAddend) {
// If we just generated a new addend, we must be it's only use.
SrcReg2 = *ReplacedAddend;
Src2IsKill = true;
} else {
SrcReg2 = Root.getOperand(IdxOtherOpd).getReg();
Src2IsKill = Root.getOperand(IdxOtherOpd).isKill();
}
if (ResultReg.isVirtual())
MRI.constrainRegClass(ResultReg, RC);
if (SrcReg0.isVirtual())
MRI.constrainRegClass(SrcReg0, RC);
if (SrcReg1.isVirtual())
MRI.constrainRegClass(SrcReg1, RC);
if (SrcReg2.isVirtual())
MRI.constrainRegClass(SrcReg2, RC);
MachineInstrBuilder MIB;
if (kind == FMAInstKind::Default)
MIB = BuildMI(MF, MIMetadata(Root), TII->get(MaddOpc), ResultReg)
.addReg(SrcReg0, getKillRegState(Src0IsKill))
.addReg(SrcReg1, getKillRegState(Src1IsKill))
.addReg(SrcReg2, getKillRegState(Src2IsKill));
else if (kind == FMAInstKind::Indexed)
MIB = BuildMI(MF, MIMetadata(Root), TII->get(MaddOpc), ResultReg)
.addReg(SrcReg2, getKillRegState(Src2IsKill))
.addReg(SrcReg0, getKillRegState(Src0IsKill))
.addReg(SrcReg1, getKillRegState(Src1IsKill))
.addImm(MUL->getOperand(3).getImm());
else if (kind == FMAInstKind::Accumulator)
MIB = BuildMI(MF, MIMetadata(Root), TII->get(MaddOpc), ResultReg)
.addReg(SrcReg2, getKillRegState(Src2IsKill))
.addReg(SrcReg0, getKillRegState(Src0IsKill))
.addReg(SrcReg1, getKillRegState(Src1IsKill));
else
assert(false && "Invalid FMA instruction kind \n");
// Insert the MADD (MADD, FMA, FMS, FMLA, FMSL)
InsInstrs.push_back(MIB);
return MUL;
}
static MachineInstr *
genFNegatedMAD(MachineFunction &MF, MachineRegisterInfo &MRI,
const TargetInstrInfo *TII, MachineInstr &Root,
SmallVectorImpl<MachineInstr *> &InsInstrs) {
MachineInstr *MAD = MRI.getUniqueVRegDef(Root.getOperand(1).getReg());
unsigned Opc = 0;
const TargetRegisterClass *RC = MRI.getRegClass(MAD->getOperand(0).getReg());
if (AArch64::FPR32RegClass.hasSubClassEq(RC))
Opc = AArch64::FNMADDSrrr;
else if (AArch64::FPR64RegClass.hasSubClassEq(RC))
Opc = AArch64::FNMADDDrrr;
else
return nullptr;
Register ResultReg = Root.getOperand(0).getReg();
Register SrcReg0 = MAD->getOperand(1).getReg();
Register SrcReg1 = MAD->getOperand(2).getReg();
Register SrcReg2 = MAD->getOperand(3).getReg();
bool Src0IsKill = MAD->getOperand(1).isKill();
bool Src1IsKill = MAD->getOperand(2).isKill();
bool Src2IsKill = MAD->getOperand(3).isKill();
if (ResultReg.isVirtual())
MRI.constrainRegClass(ResultReg, RC);
if (SrcReg0.isVirtual())
MRI.constrainRegClass(SrcReg0, RC);
if (SrcReg1.isVirtual())
MRI.constrainRegClass(SrcReg1, RC);
if (SrcReg2.isVirtual())
MRI.constrainRegClass(SrcReg2, RC);
MachineInstrBuilder MIB =
BuildMI(MF, MIMetadata(Root), TII->get(Opc), ResultReg)
.addReg(SrcReg0, getKillRegState(Src0IsKill))
.addReg(SrcReg1, getKillRegState(Src1IsKill))
.addReg(SrcReg2, getKillRegState(Src2IsKill));
InsInstrs.push_back(MIB);
return MAD;
}
/// Fold (FMUL x (DUP y lane)) into (FMUL_indexed x y lane)
static MachineInstr *
genIndexedMultiply(MachineInstr &Root,
SmallVectorImpl<MachineInstr *> &InsInstrs,
unsigned IdxDupOp, unsigned MulOpc,
const TargetRegisterClass *RC, MachineRegisterInfo &MRI) {
assert(((IdxDupOp == 1) || (IdxDupOp == 2)) &&
"Invalid index of FMUL operand");
MachineFunction &MF = *Root.getMF();
const TargetInstrInfo *TII = MF.getSubtarget().getInstrInfo();
MachineInstr *Dup =
MF.getRegInfo().getUniqueVRegDef(Root.getOperand(IdxDupOp).getReg());
if (Dup->getOpcode() == TargetOpcode::COPY)
Dup = MRI.getUniqueVRegDef(Dup->getOperand(1).getReg());
Register DupSrcReg = Dup->getOperand(1).getReg();
MRI.clearKillFlags(DupSrcReg);
MRI.constrainRegClass(DupSrcReg, RC);
unsigned DupSrcLane = Dup->getOperand(2).getImm();
unsigned IdxMulOp = IdxDupOp == 1 ? 2 : 1;
MachineOperand &MulOp = Root.getOperand(IdxMulOp);
Register ResultReg = Root.getOperand(0).getReg();
MachineInstrBuilder MIB;
MIB = BuildMI(MF, MIMetadata(Root), TII->get(MulOpc), ResultReg)
.add(MulOp)
.addReg(DupSrcReg)
.addImm(DupSrcLane);
InsInstrs.push_back(MIB);
return &Root;
}
/// genFusedMultiplyAcc - Helper to generate fused multiply accumulate
/// instructions.
///
/// \see genFusedMultiply
static MachineInstr *genFusedMultiplyAcc(
MachineFunction &MF, MachineRegisterInfo &MRI, const TargetInstrInfo *TII,
MachineInstr &Root, SmallVectorImpl<MachineInstr *> &InsInstrs,
unsigned IdxMulOpd, unsigned MaddOpc, const TargetRegisterClass *RC) {
return genFusedMultiply(MF, MRI, TII, Root, InsInstrs, IdxMulOpd, MaddOpc, RC,
FMAInstKind::Accumulator);
}
/// genNeg - Helper to generate an intermediate negation of the second operand
/// of Root
static Register genNeg(MachineFunction &MF, MachineRegisterInfo &MRI,
const TargetInstrInfo *TII, MachineInstr &Root,
SmallVectorImpl<MachineInstr *> &InsInstrs,
DenseMap<unsigned, unsigned> &InstrIdxForVirtReg,
unsigned MnegOpc, const TargetRegisterClass *RC) {
Register NewVR = MRI.createVirtualRegister(RC);
MachineInstrBuilder MIB =
BuildMI(MF, MIMetadata(Root), TII->get(MnegOpc), NewVR)
.add(Root.getOperand(2));
InsInstrs.push_back(MIB);
assert(InstrIdxForVirtReg.empty());
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
return NewVR;
}
/// genFusedMultiplyAccNeg - Helper to generate fused multiply accumulate
/// instructions with an additional negation of the accumulator
static MachineInstr *genFusedMultiplyAccNeg(
MachineFunction &MF, MachineRegisterInfo &MRI, const TargetInstrInfo *TII,
MachineInstr &Root, SmallVectorImpl<MachineInstr *> &InsInstrs,
DenseMap<unsigned, unsigned> &InstrIdxForVirtReg, unsigned IdxMulOpd,
unsigned MaddOpc, unsigned MnegOpc, const TargetRegisterClass *RC) {
assert(IdxMulOpd == 1);
Register NewVR =
genNeg(MF, MRI, TII, Root, InsInstrs, InstrIdxForVirtReg, MnegOpc, RC);
return genFusedMultiply(MF, MRI, TII, Root, InsInstrs, IdxMulOpd, MaddOpc, RC,
FMAInstKind::Accumulator, &NewVR);
}
/// genFusedMultiplyIdx - Helper to generate fused multiply accumulate
/// instructions.
///
/// \see genFusedMultiply
static MachineInstr *genFusedMultiplyIdx(
MachineFunction &MF, MachineRegisterInfo &MRI, const TargetInstrInfo *TII,
MachineInstr &Root, SmallVectorImpl<MachineInstr *> &InsInstrs,
unsigned IdxMulOpd, unsigned MaddOpc, const TargetRegisterClass *RC) {
return genFusedMultiply(MF, MRI, TII, Root, InsInstrs, IdxMulOpd, MaddOpc, RC,
FMAInstKind::Indexed);
}
/// genFusedMultiplyAccNeg - Helper to generate fused multiply accumulate
/// instructions with an additional negation of the accumulator
static MachineInstr *genFusedMultiplyIdxNeg(
MachineFunction &MF, MachineRegisterInfo &MRI, const TargetInstrInfo *TII,
MachineInstr &Root, SmallVectorImpl<MachineInstr *> &InsInstrs,
DenseMap<unsigned, unsigned> &InstrIdxForVirtReg, unsigned IdxMulOpd,
unsigned MaddOpc, unsigned MnegOpc, const TargetRegisterClass *RC) {
assert(IdxMulOpd == 1);
Register NewVR =
genNeg(MF, MRI, TII, Root, InsInstrs, InstrIdxForVirtReg, MnegOpc, RC);
return genFusedMultiply(MF, MRI, TII, Root, InsInstrs, IdxMulOpd, MaddOpc, RC,
FMAInstKind::Indexed, &NewVR);
}
/// genMaddR - Generate madd instruction and combine mul and add using
/// an extra virtual register
/// Example - an ADD intermediate needs to be stored in a register:
/// MUL I=A,B,0
/// ADD R,I,Imm
/// ==> ORR V, ZR, Imm
/// ==> MADD R,A,B,V
/// \param MF Containing MachineFunction
/// \param MRI Register information
/// \param TII Target information
/// \param Root is the ADD instruction
/// \param [out] InsInstrs is a vector of machine instructions and will
/// contain the generated madd instruction
/// \param IdxMulOpd is index of operand in Root that is the result of
/// the MUL. In the example above IdxMulOpd is 1.
/// \param MaddOpc the opcode fo the madd instruction
/// \param VR is a virtual register that holds the value of an ADD operand
/// (V in the example above).
/// \param RC Register class of operands
static MachineInstr *genMaddR(MachineFunction &MF, MachineRegisterInfo &MRI,
const TargetInstrInfo *TII, MachineInstr &Root,
SmallVectorImpl<MachineInstr *> &InsInstrs,
unsigned IdxMulOpd, unsigned MaddOpc, unsigned VR,
const TargetRegisterClass *RC) {
assert(IdxMulOpd == 1 || IdxMulOpd == 2);
MachineInstr *MUL = MRI.getUniqueVRegDef(Root.getOperand(IdxMulOpd).getReg());
Register ResultReg = Root.getOperand(0).getReg();
Register SrcReg0 = MUL->getOperand(1).getReg();
bool Src0IsKill = MUL->getOperand(1).isKill();
Register SrcReg1 = MUL->getOperand(2).getReg();
bool Src1IsKill = MUL->getOperand(2).isKill();
if (ResultReg.isVirtual())
MRI.constrainRegClass(ResultReg, RC);
if (SrcReg0.isVirtual())
MRI.constrainRegClass(SrcReg0, RC);
if (SrcReg1.isVirtual())
MRI.constrainRegClass(SrcReg1, RC);
if (Register::isVirtualRegister(VR))
MRI.constrainRegClass(VR, RC);
MachineInstrBuilder MIB =
BuildMI(MF, MIMetadata(Root), TII->get(MaddOpc), ResultReg)
.addReg(SrcReg0, getKillRegState(Src0IsKill))
.addReg(SrcReg1, getKillRegState(Src1IsKill))
.addReg(VR);
// Insert the MADD
InsInstrs.push_back(MIB);
return MUL;
}
/// Do the following transformation
/// A - (B + C) ==> (A - B) - C
/// A - (B + C) ==> (A - C) - B
static void
genSubAdd2SubSub(MachineFunction &MF, MachineRegisterInfo &MRI,
const TargetInstrInfo *TII, MachineInstr &Root,
SmallVectorImpl<MachineInstr *> &InsInstrs,
SmallVectorImpl<MachineInstr *> &DelInstrs,
unsigned IdxOpd1,
DenseMap<unsigned, unsigned> &InstrIdxForVirtReg) {
assert(IdxOpd1 == 1 || IdxOpd1 == 2);
unsigned IdxOtherOpd = IdxOpd1 == 1 ? 2 : 1;
MachineInstr *AddMI = MRI.getUniqueVRegDef(Root.getOperand(2).getReg());
Register ResultReg = Root.getOperand(0).getReg();
Register RegA = Root.getOperand(1).getReg();
bool RegAIsKill = Root.getOperand(1).isKill();
Register RegB = AddMI->getOperand(IdxOpd1).getReg();
bool RegBIsKill = AddMI->getOperand(IdxOpd1).isKill();
Register RegC = AddMI->getOperand(IdxOtherOpd).getReg();
bool RegCIsKill = AddMI->getOperand(IdxOtherOpd).isKill();
Register NewVR = MRI.createVirtualRegister(MRI.getRegClass(RegA));
unsigned Opcode = Root.getOpcode();
if (Opcode == AArch64::SUBSWrr)
Opcode = AArch64::SUBWrr;
else if (Opcode == AArch64::SUBSXrr)
Opcode = AArch64::SUBXrr;
else
assert((Opcode == AArch64::SUBWrr || Opcode == AArch64::SUBXrr) &&
"Unexpected instruction opcode.");
uint32_t Flags = Root.mergeFlagsWith(*AddMI);
Flags &= ~MachineInstr::NoSWrap;
Flags &= ~MachineInstr::NoUWrap;
MachineInstrBuilder MIB1 =
BuildMI(MF, MIMetadata(Root), TII->get(Opcode), NewVR)
.addReg(RegA, getKillRegState(RegAIsKill))
.addReg(RegB, getKillRegState(RegBIsKill))
.setMIFlags(Flags);
MachineInstrBuilder MIB2 =
BuildMI(MF, MIMetadata(Root), TII->get(Opcode), ResultReg)
.addReg(NewVR, getKillRegState(true))
.addReg(RegC, getKillRegState(RegCIsKill))
.setMIFlags(Flags);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
InsInstrs.push_back(MIB1);
InsInstrs.push_back(MIB2);
DelInstrs.push_back(AddMI);
DelInstrs.push_back(&Root);
}
/// When getMachineCombinerPatterns() finds potential patterns,
/// this function generates the instructions that could replace the
/// original code sequence
void AArch64InstrInfo::genAlternativeCodeSequence(
MachineInstr &Root, unsigned Pattern,
SmallVectorImpl<MachineInstr *> &InsInstrs,
SmallVectorImpl<MachineInstr *> &DelInstrs,
DenseMap<unsigned, unsigned> &InstrIdxForVirtReg) const {
MachineBasicBlock &MBB = *Root.getParent();
MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
MachineFunction &MF = *MBB.getParent();
const TargetInstrInfo *TII = MF.getSubtarget().getInstrInfo();
MachineInstr *MUL = nullptr;
const TargetRegisterClass *RC;
unsigned Opc;
switch (Pattern) {
default:
// Reassociate instructions.
TargetInstrInfo::genAlternativeCodeSequence(Root, Pattern, InsInstrs,
DelInstrs, InstrIdxForVirtReg);
return;
case AArch64MachineCombinerPattern::SUBADD_OP1:
// A - (B + C)
// ==> (A - B) - C
genSubAdd2SubSub(MF, MRI, TII, Root, InsInstrs, DelInstrs, 1,
InstrIdxForVirtReg);
return;
case AArch64MachineCombinerPattern::SUBADD_OP2:
// A - (B + C)
// ==> (A - C) - B
genSubAdd2SubSub(MF, MRI, TII, Root, InsInstrs, DelInstrs, 2,
InstrIdxForVirtReg);
return;
case AArch64MachineCombinerPattern::MULADDW_OP1:
case AArch64MachineCombinerPattern::MULADDX_OP1:
// MUL I=A,B,0
// ADD R,I,C
// ==> MADD R,A,B,C
// --- Create(MADD);
if (Pattern == AArch64MachineCombinerPattern::MULADDW_OP1) {
Opc = AArch64::MADDWrrr;
RC = &AArch64::GPR32RegClass;
} else {
Opc = AArch64::MADDXrrr;
RC = &AArch64::GPR64RegClass;
}
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDW_OP2:
case AArch64MachineCombinerPattern::MULADDX_OP2:
// MUL I=A,B,0
// ADD R,C,I
// ==> MADD R,A,B,C
// --- Create(MADD);
if (Pattern == AArch64MachineCombinerPattern::MULADDW_OP2) {
Opc = AArch64::MADDWrrr;
RC = &AArch64::GPR32RegClass;
} else {
Opc = AArch64::MADDXrrr;
RC = &AArch64::GPR64RegClass;
}
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDWI_OP1:
case AArch64MachineCombinerPattern::MULADDXI_OP1: {
// MUL I=A,B,0
// ADD R,I,Imm
// ==> MOV V, Imm
// ==> MADD R,A,B,V
// --- Create(MADD);
const TargetRegisterClass *OrrRC;
unsigned BitSize, OrrOpc, ZeroReg;
if (Pattern == AArch64MachineCombinerPattern::MULADDWI_OP1) {
OrrOpc = AArch64::ORRWri;
OrrRC = &AArch64::GPR32spRegClass;
BitSize = 32;
ZeroReg = AArch64::WZR;
Opc = AArch64::MADDWrrr;
RC = &AArch64::GPR32RegClass;
} else {
OrrOpc = AArch64::ORRXri;
OrrRC = &AArch64::GPR64spRegClass;
BitSize = 64;
ZeroReg = AArch64::XZR;
Opc = AArch64::MADDXrrr;
RC = &AArch64::GPR64RegClass;
}
Register NewVR = MRI.createVirtualRegister(OrrRC);
uint64_t Imm = Root.getOperand(2).getImm();
if (Root.getOperand(3).isImm()) {
unsigned Val = Root.getOperand(3).getImm();
Imm = Imm << Val;
}
uint64_t UImm = SignExtend64(Imm, BitSize);
// The immediate can be composed via a single instruction.
SmallVector<AArch64_IMM::ImmInsnModel, 4> Insn;
AArch64_IMM::expandMOVImm(UImm, BitSize, Insn);
if (Insn.size() != 1)
return;
auto MovI = Insn.begin();
MachineInstrBuilder MIB1;
// MOV is an alias for one of three instructions: movz, movn, and orr.
if (MovI->Opcode == OrrOpc)
MIB1 = BuildMI(MF, MIMetadata(Root), TII->get(OrrOpc), NewVR)
.addReg(ZeroReg)
.addImm(MovI->Op2);
else {
if (BitSize == 32)
assert((MovI->Opcode == AArch64::MOVNWi ||
MovI->Opcode == AArch64::MOVZWi) &&
"Expected opcode");
else
assert((MovI->Opcode == AArch64::MOVNXi ||
MovI->Opcode == AArch64::MOVZXi) &&
"Expected opcode");
MIB1 = BuildMI(MF, MIMetadata(Root), TII->get(MovI->Opcode), NewVR)
.addImm(MovI->Op1)
.addImm(MovI->Op2);
}
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
MUL = genMaddR(MF, MRI, TII, Root, InsInstrs, 1, Opc, NewVR, RC);
break;
}
case AArch64MachineCombinerPattern::MULSUBW_OP1:
case AArch64MachineCombinerPattern::MULSUBX_OP1: {
// MUL I=A,B,0
// SUB R,I, C
// ==> SUB V, 0, C
// ==> MADD R,A,B,V // = -C + A*B
// --- Create(MADD);
const TargetRegisterClass *SubRC;
unsigned SubOpc, ZeroReg;
if (Pattern == AArch64MachineCombinerPattern::MULSUBW_OP1) {
SubOpc = AArch64::SUBWrr;
SubRC = &AArch64::GPR32spRegClass;
ZeroReg = AArch64::WZR;
Opc = AArch64::MADDWrrr;
RC = &AArch64::GPR32RegClass;
} else {
SubOpc = AArch64::SUBXrr;
SubRC = &AArch64::GPR64spRegClass;
ZeroReg = AArch64::XZR;
Opc = AArch64::MADDXrrr;
RC = &AArch64::GPR64RegClass;
}
Register NewVR = MRI.createVirtualRegister(SubRC);
// SUB NewVR, 0, C
MachineInstrBuilder MIB1 =
BuildMI(MF, MIMetadata(Root), TII->get(SubOpc), NewVR)
.addReg(ZeroReg)
.add(Root.getOperand(2));
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
MUL = genMaddR(MF, MRI, TII, Root, InsInstrs, 1, Opc, NewVR, RC);
break;
}
case AArch64MachineCombinerPattern::MULSUBW_OP2:
case AArch64MachineCombinerPattern::MULSUBX_OP2:
// MUL I=A,B,0
// SUB R,C,I
// ==> MSUB R,A,B,C (computes C - A*B)
// --- Create(MSUB);
if (Pattern == AArch64MachineCombinerPattern::MULSUBW_OP2) {
Opc = AArch64::MSUBWrrr;
RC = &AArch64::GPR32RegClass;
} else {
Opc = AArch64::MSUBXrrr;
RC = &AArch64::GPR64RegClass;
}
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBWI_OP1:
case AArch64MachineCombinerPattern::MULSUBXI_OP1: {
// MUL I=A,B,0
// SUB R,I, Imm
// ==> MOV V, -Imm
// ==> MADD R,A,B,V // = -Imm + A*B
// --- Create(MADD);
const TargetRegisterClass *OrrRC;
unsigned BitSize, OrrOpc, ZeroReg;
if (Pattern == AArch64MachineCombinerPattern::MULSUBWI_OP1) {
OrrOpc = AArch64::ORRWri;
OrrRC = &AArch64::GPR32spRegClass;
BitSize = 32;
ZeroReg = AArch64::WZR;
Opc = AArch64::MADDWrrr;
RC = &AArch64::GPR32RegClass;
} else {
OrrOpc = AArch64::ORRXri;
OrrRC = &AArch64::GPR64spRegClass;
BitSize = 64;
ZeroReg = AArch64::XZR;
Opc = AArch64::MADDXrrr;
RC = &AArch64::GPR64RegClass;
}
Register NewVR = MRI.createVirtualRegister(OrrRC);
uint64_t Imm = Root.getOperand(2).getImm();
if (Root.getOperand(3).isImm()) {
unsigned Val = Root.getOperand(3).getImm();
Imm = Imm << Val;
}
uint64_t UImm = SignExtend64(-Imm, BitSize);
// The immediate can be composed via a single instruction.
SmallVector<AArch64_IMM::ImmInsnModel, 4> Insn;
AArch64_IMM::expandMOVImm(UImm, BitSize, Insn);
if (Insn.size() != 1)
return;
auto MovI = Insn.begin();
MachineInstrBuilder MIB1;
// MOV is an alias for one of three instructions: movz, movn, and orr.
if (MovI->Opcode == OrrOpc)
MIB1 = BuildMI(MF, MIMetadata(Root), TII->get(OrrOpc), NewVR)
.addReg(ZeroReg)
.addImm(MovI->Op2);
else {
if (BitSize == 32)
assert((MovI->Opcode == AArch64::MOVNWi ||
MovI->Opcode == AArch64::MOVZWi) &&
"Expected opcode");
else
assert((MovI->Opcode == AArch64::MOVNXi ||
MovI->Opcode == AArch64::MOVZXi) &&
"Expected opcode");
MIB1 = BuildMI(MF, MIMetadata(Root), TII->get(MovI->Opcode), NewVR)
.addImm(MovI->Op1)
.addImm(MovI->Op2);
}
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
MUL = genMaddR(MF, MRI, TII, Root, InsInstrs, 1, Opc, NewVR, RC);
break;
}
case AArch64MachineCombinerPattern::MULADDv8i8_OP1:
Opc = AArch64::MLAv8i8;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv8i8_OP2:
Opc = AArch64::MLAv8i8;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv16i8_OP1:
Opc = AArch64::MLAv16i8;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv16i8_OP2:
Opc = AArch64::MLAv16i8;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i16_OP1:
Opc = AArch64::MLAv4i16;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i16_OP2:
Opc = AArch64::MLAv4i16;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv8i16_OP1:
Opc = AArch64::MLAv8i16;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv8i16_OP2:
Opc = AArch64::MLAv8i16;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv2i32_OP1:
Opc = AArch64::MLAv2i32;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv2i32_OP2:
Opc = AArch64::MLAv2i32;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i32_OP1:
Opc = AArch64::MLAv4i32;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i32_OP2:
Opc = AArch64::MLAv4i32;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv8i8_OP1:
Opc = AArch64::MLAv8i8;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAccNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv8i8,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv8i8_OP2:
Opc = AArch64::MLSv8i8;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv16i8_OP1:
Opc = AArch64::MLAv16i8;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAccNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv16i8,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv16i8_OP2:
Opc = AArch64::MLSv16i8;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i16_OP1:
Opc = AArch64::MLAv4i16;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAccNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv4i16,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i16_OP2:
Opc = AArch64::MLSv4i16;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv8i16_OP1:
Opc = AArch64::MLAv8i16;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAccNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv8i16,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv8i16_OP2:
Opc = AArch64::MLSv8i16;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv2i32_OP1:
Opc = AArch64::MLAv2i32;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAccNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv2i32,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv2i32_OP2:
Opc = AArch64::MLSv2i32;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i32_OP1:
Opc = AArch64::MLAv4i32;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAccNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv4i32,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i32_OP2:
Opc = AArch64::MLSv4i32;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyAcc(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i16_indexed_OP1:
Opc = AArch64::MLAv4i16_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i16_indexed_OP2:
Opc = AArch64::MLAv4i16_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv8i16_indexed_OP1:
Opc = AArch64::MLAv8i16_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv8i16_indexed_OP2:
Opc = AArch64::MLAv8i16_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv2i32_indexed_OP1:
Opc = AArch64::MLAv2i32_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv2i32_indexed_OP2:
Opc = AArch64::MLAv2i32_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i32_indexed_OP1:
Opc = AArch64::MLAv4i32_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULADDv4i32_indexed_OP2:
Opc = AArch64::MLAv4i32_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i16_indexed_OP1:
Opc = AArch64::MLAv4i16_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdxNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv4i16,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i16_indexed_OP2:
Opc = AArch64::MLSv4i16_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv8i16_indexed_OP1:
Opc = AArch64::MLAv8i16_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdxNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv8i16,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv8i16_indexed_OP2:
Opc = AArch64::MLSv8i16_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv2i32_indexed_OP1:
Opc = AArch64::MLAv2i32_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdxNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv2i32,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv2i32_indexed_OP2:
Opc = AArch64::MLSv2i32_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i32_indexed_OP1:
Opc = AArch64::MLAv4i32_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdxNeg(MF, MRI, TII, Root, InsInstrs,
InstrIdxForVirtReg, 1, Opc, AArch64::NEGv4i32,
RC);
break;
case AArch64MachineCombinerPattern::MULSUBv4i32_indexed_OP2:
Opc = AArch64::MLSv4i32_indexed;
RC = &AArch64::FPR128RegClass;
MUL = genFusedMultiplyIdx(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
// Floating Point Support
case AArch64MachineCombinerPattern::FMULADDH_OP1:
Opc = AArch64::FMADDHrrr;
RC = &AArch64::FPR16RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULADDS_OP1:
Opc = AArch64::FMADDSrrr;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULADDD_OP1:
Opc = AArch64::FMADDDrrr;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULADDH_OP2:
Opc = AArch64::FMADDHrrr;
RC = &AArch64::FPR16RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULADDS_OP2:
Opc = AArch64::FMADDSrrr;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULADDD_OP2:
Opc = AArch64::FMADDDrrr;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMLAv1i32_indexed_OP1:
Opc = AArch64::FMLAv1i32_indexed;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv1i32_indexed_OP2:
Opc = AArch64::FMLAv1i32_indexed;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv1i64_indexed_OP1:
Opc = AArch64::FMLAv1i64_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv1i64_indexed_OP2:
Opc = AArch64::FMLAv1i64_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv4i16_indexed_OP1:
RC = &AArch64::FPR64RegClass;
Opc = AArch64::FMLAv4i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv4f16_OP1:
RC = &AArch64::FPR64RegClass;
Opc = AArch64::FMLAv4f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator);
break;
case AArch64MachineCombinerPattern::FMLAv4i16_indexed_OP2:
RC = &AArch64::FPR64RegClass;
Opc = AArch64::FMLAv4i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv4f16_OP2:
RC = &AArch64::FPR64RegClass;
Opc = AArch64::FMLAv4f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
break;
case AArch64MachineCombinerPattern::FMLAv2i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv2f32_OP1:
RC = &AArch64::FPR64RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLAv2i32_indexed_OP1) {
Opc = AArch64::FMLAv2i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLAv2f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLAv2i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv2f32_OP2:
RC = &AArch64::FPR64RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLAv2i32_indexed_OP2) {
Opc = AArch64::FMLAv2i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLAv2f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLAv8i16_indexed_OP1:
RC = &AArch64::FPR128RegClass;
Opc = AArch64::FMLAv8i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv8f16_OP1:
RC = &AArch64::FPR128RegClass;
Opc = AArch64::FMLAv8f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator);
break;
case AArch64MachineCombinerPattern::FMLAv8i16_indexed_OP2:
RC = &AArch64::FPR128RegClass;
Opc = AArch64::FMLAv8i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLAv8f16_OP2:
RC = &AArch64::FPR128RegClass;
Opc = AArch64::FMLAv8f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
break;
case AArch64MachineCombinerPattern::FMLAv2i64_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv2f64_OP1:
RC = &AArch64::FPR128RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLAv2i64_indexed_OP1) {
Opc = AArch64::FMLAv2i64_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLAv2f64;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLAv2i64_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv2f64_OP2:
RC = &AArch64::FPR128RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLAv2i64_indexed_OP2) {
Opc = AArch64::FMLAv2i64_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLAv2f64;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLAv4i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMLAv4f32_OP1:
RC = &AArch64::FPR128RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLAv4i32_indexed_OP1) {
Opc = AArch64::FMLAv4i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLAv4f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLAv4i32_indexed_OP2:
case AArch64MachineCombinerPattern::FMLAv4f32_OP2:
RC = &AArch64::FPR128RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLAv4i32_indexed_OP2) {
Opc = AArch64::FMLAv4i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLAv4f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMULSUBH_OP1:
Opc = AArch64::FNMSUBHrrr;
RC = &AArch64::FPR16RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULSUBS_OP1:
Opc = AArch64::FNMSUBSrrr;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULSUBD_OP1:
Opc = AArch64::FNMSUBDrrr;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FNMULSUBH_OP1:
Opc = AArch64::FNMADDHrrr;
RC = &AArch64::FPR16RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FNMULSUBS_OP1:
Opc = AArch64::FNMADDSrrr;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FNMULSUBD_OP1:
Opc = AArch64::FNMADDDrrr;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULSUBH_OP2:
Opc = AArch64::FMSUBHrrr;
RC = &AArch64::FPR16RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULSUBS_OP2:
Opc = AArch64::FMSUBSrrr;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMULSUBD_OP2:
Opc = AArch64::FMSUBDrrr;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC);
break;
case AArch64MachineCombinerPattern::FMLSv1i32_indexed_OP2:
Opc = AArch64::FMLSv1i32_indexed;
RC = &AArch64::FPR32RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLSv1i64_indexed_OP2:
Opc = AArch64::FMLSv1i64_indexed;
RC = &AArch64::FPR64RegClass;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLSv4f16_OP1:
case AArch64MachineCombinerPattern::FMLSv4i16_indexed_OP1: {
RC = &AArch64::FPR64RegClass;
Register NewVR = MRI.createVirtualRegister(RC);
MachineInstrBuilder MIB1 =
BuildMI(MF, MIMetadata(Root), TII->get(AArch64::FNEGv4f16), NewVR)
.add(Root.getOperand(2));
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
if (Pattern == AArch64MachineCombinerPattern::FMLSv4f16_OP1) {
Opc = AArch64::FMLAv4f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator, &NewVR);
} else {
Opc = AArch64::FMLAv4i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed, &NewVR);
}
break;
}
case AArch64MachineCombinerPattern::FMLSv4f16_OP2:
RC = &AArch64::FPR64RegClass;
Opc = AArch64::FMLSv4f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
break;
case AArch64MachineCombinerPattern::FMLSv4i16_indexed_OP2:
RC = &AArch64::FPR64RegClass;
Opc = AArch64::FMLSv4i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLSv2f32_OP2:
case AArch64MachineCombinerPattern::FMLSv2i32_indexed_OP2:
RC = &AArch64::FPR64RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLSv2i32_indexed_OP2) {
Opc = AArch64::FMLSv2i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLSv2f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLSv8f16_OP1:
case AArch64MachineCombinerPattern::FMLSv8i16_indexed_OP1: {
RC = &AArch64::FPR128RegClass;
Register NewVR = MRI.createVirtualRegister(RC);
MachineInstrBuilder MIB1 =
BuildMI(MF, MIMetadata(Root), TII->get(AArch64::FNEGv8f16), NewVR)
.add(Root.getOperand(2));
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
if (Pattern == AArch64MachineCombinerPattern::FMLSv8f16_OP1) {
Opc = AArch64::FMLAv8f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator, &NewVR);
} else {
Opc = AArch64::FMLAv8i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed, &NewVR);
}
break;
}
case AArch64MachineCombinerPattern::FMLSv8f16_OP2:
RC = &AArch64::FPR128RegClass;
Opc = AArch64::FMLSv8f16;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
break;
case AArch64MachineCombinerPattern::FMLSv8i16_indexed_OP2:
RC = &AArch64::FPR128RegClass;
Opc = AArch64::FMLSv8i16_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
break;
case AArch64MachineCombinerPattern::FMLSv2f64_OP2:
case AArch64MachineCombinerPattern::FMLSv2i64_indexed_OP2:
RC = &AArch64::FPR128RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLSv2i64_indexed_OP2) {
Opc = AArch64::FMLSv2i64_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLSv2f64;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLSv4f32_OP2:
case AArch64MachineCombinerPattern::FMLSv4i32_indexed_OP2:
RC = &AArch64::FPR128RegClass;
if (Pattern == AArch64MachineCombinerPattern::FMLSv4i32_indexed_OP2) {
Opc = AArch64::FMLSv4i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Indexed);
} else {
Opc = AArch64::FMLSv4f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 2, Opc, RC,
FMAInstKind::Accumulator);
}
break;
case AArch64MachineCombinerPattern::FMLSv2f32_OP1:
case AArch64MachineCombinerPattern::FMLSv2i32_indexed_OP1: {
RC = &AArch64::FPR64RegClass;
Register NewVR = MRI.createVirtualRegister(RC);
MachineInstrBuilder MIB1 =
BuildMI(MF, MIMetadata(Root), TII->get(AArch64::FNEGv2f32), NewVR)
.add(Root.getOperand(2));
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
if (Pattern == AArch64MachineCombinerPattern::FMLSv2i32_indexed_OP1) {
Opc = AArch64::FMLAv2i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed, &NewVR);
} else {
Opc = AArch64::FMLAv2f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator, &NewVR);
}
break;
}
case AArch64MachineCombinerPattern::FMLSv4f32_OP1:
case AArch64MachineCombinerPattern::FMLSv4i32_indexed_OP1: {
RC = &AArch64::FPR128RegClass;
Register NewVR = MRI.createVirtualRegister(RC);
MachineInstrBuilder MIB1 =
BuildMI(MF, MIMetadata(Root), TII->get(AArch64::FNEGv4f32), NewVR)
.add(Root.getOperand(2));
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
if (Pattern == AArch64MachineCombinerPattern::FMLSv4i32_indexed_OP1) {
Opc = AArch64::FMLAv4i32_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed, &NewVR);
} else {
Opc = AArch64::FMLAv4f32;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator, &NewVR);
}
break;
}
case AArch64MachineCombinerPattern::FMLSv2f64_OP1:
case AArch64MachineCombinerPattern::FMLSv2i64_indexed_OP1: {
RC = &AArch64::FPR128RegClass;
Register NewVR = MRI.createVirtualRegister(RC);
MachineInstrBuilder MIB1 =
BuildMI(MF, MIMetadata(Root), TII->get(AArch64::FNEGv2f64), NewVR)
.add(Root.getOperand(2));
InsInstrs.push_back(MIB1);
InstrIdxForVirtReg.insert(std::make_pair(NewVR, 0));
if (Pattern == AArch64MachineCombinerPattern::FMLSv2i64_indexed_OP1) {
Opc = AArch64::FMLAv2i64_indexed;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Indexed, &NewVR);
} else {
Opc = AArch64::FMLAv2f64;
MUL = genFusedMultiply(MF, MRI, TII, Root, InsInstrs, 1, Opc, RC,
FMAInstKind::Accumulator, &NewVR);
}
break;
}
case AArch64MachineCombinerPattern::FMULv2i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv2i32_indexed_OP2: {
unsigned IdxDupOp =
(Pattern == AArch64MachineCombinerPattern::FMULv2i32_indexed_OP1) ? 1
: 2;
genIndexedMultiply(Root, InsInstrs, IdxDupOp, AArch64::FMULv2i32_indexed,
&AArch64::FPR128RegClass, MRI);
break;
}
case AArch64MachineCombinerPattern::FMULv2i64_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv2i64_indexed_OP2: {
unsigned IdxDupOp =
(Pattern == AArch64MachineCombinerPattern::FMULv2i64_indexed_OP1) ? 1
: 2;
genIndexedMultiply(Root, InsInstrs, IdxDupOp, AArch64::FMULv2i64_indexed,
&AArch64::FPR128RegClass, MRI);
break;
}
case AArch64MachineCombinerPattern::FMULv4i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv4i16_indexed_OP2: {
unsigned IdxDupOp =
(Pattern == AArch64MachineCombinerPattern::FMULv4i16_indexed_OP1) ? 1
: 2;
genIndexedMultiply(Root, InsInstrs, IdxDupOp, AArch64::FMULv4i16_indexed,
&AArch64::FPR128_loRegClass, MRI);
break;
}
case AArch64MachineCombinerPattern::FMULv4i32_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv4i32_indexed_OP2: {
unsigned IdxDupOp =
(Pattern == AArch64MachineCombinerPattern::FMULv4i32_indexed_OP1) ? 1
: 2;
genIndexedMultiply(Root, InsInstrs, IdxDupOp, AArch64::FMULv4i32_indexed,
&AArch64::FPR128RegClass, MRI);
break;
}
case AArch64MachineCombinerPattern::FMULv8i16_indexed_OP1:
case AArch64MachineCombinerPattern::FMULv8i16_indexed_OP2: {
unsigned IdxDupOp =
(Pattern == AArch64MachineCombinerPattern::FMULv8i16_indexed_OP1) ? 1
: 2;
genIndexedMultiply(Root, InsInstrs, IdxDupOp, AArch64::FMULv8i16_indexed,
&AArch64::FPR128_loRegClass, MRI);
break;
}
case AArch64MachineCombinerPattern::FNMADD: {
MUL = genFNegatedMAD(MF, MRI, TII, Root, InsInstrs);
break;
}
} // end switch (Pattern)
// Record MUL and ADD/SUB for deletion
if (MUL)
DelInstrs.push_back(MUL);
DelInstrs.push_back(&Root);
// Set the flags on the inserted instructions to be the merged flags of the
// instructions that we have combined.
uint32_t Flags = Root.getFlags();
if (MUL)
Flags = Root.mergeFlagsWith(*MUL);
for (auto *MI : InsInstrs)
MI->setFlags(Flags);
}
/// Replace csincr-branch sequence by simple conditional branch
///
/// Examples:
/// 1. \code
/// csinc w9, wzr, wzr, <condition code>
/// tbnz w9, #0, 0x44
/// \endcode
/// to
/// \code
/// b.<inverted condition code>
/// \endcode
///
/// 2. \code
/// csinc w9, wzr, wzr, <condition code>
/// tbz w9, #0, 0x44
/// \endcode
/// to
/// \code
/// b.<condition code>
/// \endcode
///
/// Replace compare and branch sequence by TBZ/TBNZ instruction when the
/// compare's constant operand is power of 2.
///
/// Examples:
/// \code
/// and w8, w8, #0x400
/// cbnz w8, L1
/// \endcode
/// to
/// \code
/// tbnz w8, #10, L1
/// \endcode
///
/// \param MI Conditional Branch
/// \return True when the simple conditional branch is generated
///
bool AArch64InstrInfo::optimizeCondBranch(MachineInstr &MI) const {
bool IsNegativeBranch = false;
bool IsTestAndBranch = false;
unsigned TargetBBInMI = 0;
switch (MI.getOpcode()) {
default:
llvm_unreachable("Unknown branch instruction?");
case AArch64::Bcc:
return false;
case AArch64::CBZW:
case AArch64::CBZX:
TargetBBInMI = 1;
break;
case AArch64::CBNZW:
case AArch64::CBNZX:
TargetBBInMI = 1;
IsNegativeBranch = true;
break;
case AArch64::TBZW:
case AArch64::TBZX:
TargetBBInMI = 2;
IsTestAndBranch = true;
break;
case AArch64::TBNZW:
case AArch64::TBNZX:
TargetBBInMI = 2;
IsNegativeBranch = true;
IsTestAndBranch = true;
break;
}
// So we increment a zero register and test for bits other
// than bit 0? Conservatively bail out in case the verifier
// missed this case.
if (IsTestAndBranch && MI.getOperand(1).getImm())
return false;
// Find Definition.
assert(MI.getParent() && "Incomplete machine instruciton\n");
MachineBasicBlock *MBB = MI.getParent();
MachineFunction *MF = MBB->getParent();
MachineRegisterInfo *MRI = &MF->getRegInfo();
Register VReg = MI.getOperand(0).getReg();
if (!VReg.isVirtual())
return false;
MachineInstr *DefMI = MRI->getVRegDef(VReg);
// Look through COPY instructions to find definition.
while (DefMI->isCopy()) {
Register CopyVReg = DefMI->getOperand(1).getReg();
if (!MRI->hasOneNonDBGUse(CopyVReg))
return false;
if (!MRI->hasOneDef(CopyVReg))
return false;
DefMI = MRI->getVRegDef(CopyVReg);
}
switch (DefMI->getOpcode()) {
default:
return false;
// Fold AND into a TBZ/TBNZ if constant operand is power of 2.
case AArch64::ANDWri:
case AArch64::ANDXri: {
if (IsTestAndBranch)
return false;
if (DefMI->getParent() != MBB)
return false;
if (!MRI->hasOneNonDBGUse(VReg))
return false;
bool Is32Bit = (DefMI->getOpcode() == AArch64::ANDWri);
uint64_t Mask = AArch64_AM::decodeLogicalImmediate(
DefMI->getOperand(2).getImm(), Is32Bit ? 32 : 64);
if (!isPowerOf2_64(Mask))
return false;
MachineOperand &MO = DefMI->getOperand(1);
Register NewReg = MO.getReg();
if (!NewReg.isVirtual())
return false;
assert(!MRI->def_empty(NewReg) && "Register must be defined.");
MachineBasicBlock &RefToMBB = *MBB;
MachineBasicBlock *TBB = MI.getOperand(1).getMBB();
DebugLoc DL = MI.getDebugLoc();
unsigned Imm = Log2_64(Mask);
unsigned Opc = (Imm < 32)
? (IsNegativeBranch ? AArch64::TBNZW : AArch64::TBZW)
: (IsNegativeBranch ? AArch64::TBNZX : AArch64::TBZX);
MachineInstr *NewMI = BuildMI(RefToMBB, MI, DL, get(Opc))
.addReg(NewReg)
.addImm(Imm)
.addMBB(TBB);
// Register lives on to the CBZ now.
MO.setIsKill(false);
// For immediate smaller than 32, we need to use the 32-bit
// variant (W) in all cases. Indeed the 64-bit variant does not
// allow to encode them.
// Therefore, if the input register is 64-bit, we need to take the
// 32-bit sub-part.
if (!Is32Bit && Imm < 32)
NewMI->getOperand(0).setSubReg(AArch64::sub_32);
MI.eraseFromParent();
return true;
}
// Look for CSINC
case AArch64::CSINCWr:
case AArch64::CSINCXr: {
if (!(DefMI->getOperand(1).getReg() == AArch64::WZR &&
DefMI->getOperand(2).getReg() == AArch64::WZR) &&
!(DefMI->getOperand(1).getReg() == AArch64::XZR &&
DefMI->getOperand(2).getReg() == AArch64::XZR))
return false;
if (DefMI->findRegisterDefOperandIdx(AArch64::NZCV, /*TRI=*/nullptr,
true) != -1)
return false;
AArch64CC::CondCode CC = (AArch64CC::CondCode)DefMI->getOperand(3).getImm();
// Convert only when the condition code is not modified between
// the CSINC and the branch. The CC may be used by other
// instructions in between.
if (areCFlagsAccessedBetweenInstrs(DefMI, MI, &getRegisterInfo(), AK_Write))
return false;
MachineBasicBlock &RefToMBB = *MBB;
MachineBasicBlock *TBB = MI.getOperand(TargetBBInMI).getMBB();
DebugLoc DL = MI.getDebugLoc();
if (IsNegativeBranch)
CC = AArch64CC::getInvertedCondCode(CC);
BuildMI(RefToMBB, MI, DL, get(AArch64::Bcc)).addImm(CC).addMBB(TBB);
MI.eraseFromParent();
return true;
}
}
}
std::pair<unsigned, unsigned>
AArch64InstrInfo::decomposeMachineOperandsTargetFlags(unsigned TF) const {
const unsigned Mask = AArch64II::MO_FRAGMENT;
return std::make_pair(TF & Mask, TF & ~Mask);
}
ArrayRef<std::pair<unsigned, const char *>>
AArch64InstrInfo::getSerializableDirectMachineOperandTargetFlags() const {
using namespace AArch64II;
static const std::pair<unsigned, const char *> TargetFlags[] = {
{MO_PAGE, "aarch64-page"}, {MO_PAGEOFF, "aarch64-pageoff"},
{MO_G3, "aarch64-g3"}, {MO_G2, "aarch64-g2"},
{MO_G1, "aarch64-g1"}, {MO_G0, "aarch64-g0"},
{MO_HI12, "aarch64-hi12"}};
return ArrayRef(TargetFlags);
}
ArrayRef<std::pair<unsigned, const char *>>
AArch64InstrInfo::getSerializableBitmaskMachineOperandTargetFlags() const {
using namespace AArch64II;
static const std::pair<unsigned, const char *> TargetFlags[] = {
{MO_COFFSTUB, "aarch64-coffstub"},
{MO_GOT, "aarch64-got"},
{MO_NC, "aarch64-nc"},
{MO_S, "aarch64-s"},
{MO_TLS, "aarch64-tls"},
{MO_DLLIMPORT, "aarch64-dllimport"},
{MO_PREL, "aarch64-prel"},
{MO_TAGGED, "aarch64-tagged"},
{MO_ARM64EC_CALLMANGLE, "aarch64-arm64ec-callmangle"},
};
return ArrayRef(TargetFlags);
}
ArrayRef<std::pair<MachineMemOperand::Flags, const char *>>
AArch64InstrInfo::getSerializableMachineMemOperandTargetFlags() const {
static const std::pair<MachineMemOperand::Flags, const char *> TargetFlags[] =
{{MOSuppressPair, "aarch64-suppress-pair"},
{MOStridedAccess, "aarch64-strided-access"}};
return ArrayRef(TargetFlags);
}
/// Constants defining how certain sequences should be outlined.
/// This encompasses how an outlined function should be called, and what kind of
/// frame should be emitted for that outlined function.
///
/// \p MachineOutlinerDefault implies that the function should be called with
/// a save and restore of LR to the stack.
///
/// That is,
///
/// I1 Save LR OUTLINED_FUNCTION:
/// I2 --> BL OUTLINED_FUNCTION I1
/// I3 Restore LR I2
/// I3
/// RET
///
/// * Call construction overhead: 3 (save + BL + restore)
/// * Frame construction overhead: 1 (ret)
/// * Requires stack fixups? Yes
///
/// \p MachineOutlinerTailCall implies that the function is being created from
/// a sequence of instructions ending in a return.
///
/// That is,
///
/// I1 OUTLINED_FUNCTION:
/// I2 --> B OUTLINED_FUNCTION I1
/// RET I2
/// RET
///
/// * Call construction overhead: 1 (B)
/// * Frame construction overhead: 0 (Return included in sequence)
/// * Requires stack fixups? No
///
/// \p MachineOutlinerNoLRSave implies that the function should be called using
/// a BL instruction, but doesn't require LR to be saved and restored. This
/// happens when LR is known to be dead.
///
/// That is,
///
/// I1 OUTLINED_FUNCTION:
/// I2 --> BL OUTLINED_FUNCTION I1
/// I3 I2
/// I3
/// RET
///
/// * Call construction overhead: 1 (BL)
/// * Frame construction overhead: 1 (RET)
/// * Requires stack fixups? No
///
/// \p MachineOutlinerThunk implies that the function is being created from
/// a sequence of instructions ending in a call. The outlined function is
/// called with a BL instruction, and the outlined function tail-calls the
/// original call destination.
///
/// That is,
///
/// I1 OUTLINED_FUNCTION:
/// I2 --> BL OUTLINED_FUNCTION I1
/// BL f I2
/// B f
/// * Call construction overhead: 1 (BL)
/// * Frame construction overhead: 0
/// * Requires stack fixups? No
///
/// \p MachineOutlinerRegSave implies that the function should be called with a
/// save and restore of LR to an available register. This allows us to avoid
/// stack fixups. Note that this outlining variant is compatible with the
/// NoLRSave case.
///
/// That is,
///
/// I1 Save LR OUTLINED_FUNCTION:
/// I2 --> BL OUTLINED_FUNCTION I1
/// I3 Restore LR I2
/// I3
/// RET
///
/// * Call construction overhead: 3 (save + BL + restore)
/// * Frame construction overhead: 1 (ret)
/// * Requires stack fixups? No
enum MachineOutlinerClass {
MachineOutlinerDefault, /// Emit a save, restore, call, and return.
MachineOutlinerTailCall, /// Only emit a branch.
MachineOutlinerNoLRSave, /// Emit a call and return.
MachineOutlinerThunk, /// Emit a call and tail-call.
MachineOutlinerRegSave /// Same as default, but save to a register.
};
enum MachineOutlinerMBBFlags {
LRUnavailableSomewhere = 0x2,
HasCalls = 0x4,
UnsafeRegsDead = 0x8
};
Register
AArch64InstrInfo::findRegisterToSaveLRTo(outliner::Candidate &C) const {
MachineFunction *MF = C.getMF();
const TargetRegisterInfo &TRI = *MF->getSubtarget().getRegisterInfo();
const AArch64RegisterInfo *ARI =
static_cast<const AArch64RegisterInfo *>(&TRI);
// Check if there is an available register across the sequence that we can
// use.
for (unsigned Reg : AArch64::GPR64RegClass) {
if (!ARI->isReservedReg(*MF, Reg) &&
Reg != AArch64::LR && // LR is not reserved, but don't use it.
Reg != AArch64::X16 && // X16 is not guaranteed to be preserved.
Reg != AArch64::X17 && // Ditto for X17.
C.isAvailableAcrossAndOutOfSeq(Reg, TRI) &&
C.isAvailableInsideSeq(Reg, TRI))
return Reg;
}
return Register();
}
static bool
outliningCandidatesSigningScopeConsensus(const outliner::Candidate &a,
const outliner::Candidate &b) {
const auto &MFIa = a.getMF()->getInfo<AArch64FunctionInfo>();
const auto &MFIb = b.getMF()->getInfo<AArch64FunctionInfo>();
return MFIa->shouldSignReturnAddress(false) == MFIb->shouldSignReturnAddress(false) &&
MFIa->shouldSignReturnAddress(true) == MFIb->shouldSignReturnAddress(true);
}
static bool
outliningCandidatesSigningKeyConsensus(const outliner::Candidate &a,
const outliner::Candidate &b) {
const auto &MFIa = a.getMF()->getInfo<AArch64FunctionInfo>();
const auto &MFIb = b.getMF()->getInfo<AArch64FunctionInfo>();
return MFIa->shouldSignWithBKey() == MFIb->shouldSignWithBKey();
}
static bool outliningCandidatesV8_3OpsConsensus(const outliner::Candidate &a,
const outliner::Candidate &b) {
const AArch64Subtarget &SubtargetA =
a.getMF()->getSubtarget<AArch64Subtarget>();
const AArch64Subtarget &SubtargetB =
b.getMF()->getSubtarget<AArch64Subtarget>();
return SubtargetA.hasV8_3aOps() == SubtargetB.hasV8_3aOps();
}
std::optional<outliner::OutlinedFunction>
AArch64InstrInfo::getOutliningCandidateInfo(
std::vector<outliner::Candidate> &RepeatedSequenceLocs) const {
outliner::Candidate &FirstCand = RepeatedSequenceLocs[0];
unsigned SequenceSize = 0;
for (auto &MI : FirstCand)
SequenceSize += getInstSizeInBytes(MI);
unsigned NumBytesToCreateFrame = 0;
// We only allow outlining for functions having exactly matching return
// address signing attributes, i.e., all share the same value for the
// attribute "sign-return-address" and all share the same type of key they
// are signed with.
// Additionally we require all functions to simultaniously either support
// v8.3a features or not. Otherwise an outlined function could get signed
// using dedicated v8.3 instructions and a call from a function that doesn't
// support v8.3 instructions would therefore be invalid.
if (std::adjacent_find(
RepeatedSequenceLocs.begin(), RepeatedSequenceLocs.end(),
[](const outliner::Candidate &a, const outliner::Candidate &b) {
// Return true if a and b are non-equal w.r.t. return address
// signing or support of v8.3a features
if (outliningCandidatesSigningScopeConsensus(a, b) &&
outliningCandidatesSigningKeyConsensus(a, b) &&
outliningCandidatesV8_3OpsConsensus(a, b)) {
return false;
}
return true;
}) != RepeatedSequenceLocs.end()) {
return std::nullopt;
}
// Since at this point all candidates agree on their return address signing
// picking just one is fine. If the candidate functions potentially sign their
// return addresses, the outlined function should do the same. Note that in
// the case of "sign-return-address"="non-leaf" this is an assumption: It is
// not certainly true that the outlined function will have to sign its return
// address but this decision is made later, when the decision to outline
// has already been made.
// The same holds for the number of additional instructions we need: On
// v8.3a RET can be replaced by RETAA/RETAB and no AUT instruction is
// necessary. However, at this point we don't know if the outlined function
// will have a RET instruction so we assume the worst.
const TargetRegisterInfo &TRI = getRegisterInfo();
// Performing a tail call may require extra checks when PAuth is enabled.
// If PAuth is disabled, set it to zero for uniformity.
unsigned NumBytesToCheckLRInTCEpilogue = 0;
if (FirstCand.getMF()
->getInfo<AArch64FunctionInfo>()
->shouldSignReturnAddress(true)) {
// One PAC and one AUT instructions
NumBytesToCreateFrame += 8;
// PAuth is enabled - set extra tail call cost, if any.
auto LRCheckMethod = Subtarget.getAuthenticatedLRCheckMethod();
NumBytesToCheckLRInTCEpilogue =
AArch64PAuth::getCheckerSizeInBytes(LRCheckMethod);
// Checking the authenticated LR value may significantly impact
// SequenceSize, so account for it for more precise results.
if (isTailCallReturnInst(RepeatedSequenceLocs[0].back()))
SequenceSize += NumBytesToCheckLRInTCEpilogue;
// We have to check if sp modifying instructions would get outlined.
// If so we only allow outlining if sp is unchanged overall, so matching
// sub and add instructions are okay to outline, all other sp modifications
// are not
auto hasIllegalSPModification = [&TRI](outliner::Candidate &C) {
int SPValue = 0;
for (auto &MI : C) {
if (MI.modifiesRegister(AArch64::SP, &TRI)) {
switch (MI.getOpcode()) {
case AArch64::ADDXri:
case AArch64::ADDWri:
assert(MI.getNumOperands() == 4 && "Wrong number of operands");
assert(MI.getOperand(2).isImm() &&
"Expected operand to be immediate");
assert(MI.getOperand(1).isReg() &&
"Expected operand to be a register");
// Check if the add just increments sp. If so, we search for
// matching sub instructions that decrement sp. If not, the
// modification is illegal
if (MI.getOperand(1).getReg() == AArch64::SP)
SPValue += MI.getOperand(2).getImm();
else
return true;
break;
case AArch64::SUBXri:
case AArch64::SUBWri:
assert(MI.getNumOperands() == 4 && "Wrong number of operands");
assert(MI.getOperand(2).isImm() &&
"Expected operand to be immediate");
assert(MI.getOperand(1).isReg() &&
"Expected operand to be a register");
// Check if the sub just decrements sp. If so, we search for
// matching add instructions that increment sp. If not, the
// modification is illegal
if (MI.getOperand(1).getReg() == AArch64::SP)
SPValue -= MI.getOperand(2).getImm();
else
return true;
break;
default:
return true;
}
}
}
if (SPValue)
return true;
return false;
};
// Remove candidates with illegal stack modifying instructions
llvm::erase_if(RepeatedSequenceLocs, hasIllegalSPModification);
// If the sequence doesn't have enough candidates left, then we're done.
if (RepeatedSequenceLocs.size() < 2)
return std::nullopt;
}
// Properties about candidate MBBs that hold for all of them.
unsigned FlagsSetInAll = 0xF;
// Compute liveness information for each candidate, and set FlagsSetInAll.
for (outliner::Candidate &C : RepeatedSequenceLocs)
FlagsSetInAll &= C.Flags;
unsigned LastInstrOpcode = RepeatedSequenceLocs[0].back().getOpcode();
// Helper lambda which sets call information for every candidate.
auto SetCandidateCallInfo =
[&RepeatedSequenceLocs](unsigned CallID, unsigned NumBytesForCall) {
for (outliner::Candidate &C : RepeatedSequenceLocs)
C.setCallInfo(CallID, NumBytesForCall);
};
unsigned FrameID = MachineOutlinerDefault;
NumBytesToCreateFrame += 4;
bool HasBTI = any_of(RepeatedSequenceLocs, [](outliner::Candidate &C) {
return C.getMF()->getInfo<AArch64FunctionInfo>()->branchTargetEnforcement();
});
// We check to see if CFI Instructions are present, and if they are
// we find the number of CFI Instructions in the candidates.
unsigned CFICount = 0;
for (auto &I : RepeatedSequenceLocs[0]) {
if (I.isCFIInstruction())
CFICount++;
}
// We compare the number of found CFI Instructions to the number of CFI
// instructions in the parent function for each candidate. We must check this
// since if we outline one of the CFI instructions in a function, we have to
// outline them all for correctness. If we do not, the address offsets will be
// incorrect between the two sections of the program.
for (outliner::Candidate &C : RepeatedSequenceLocs) {
std::vector<MCCFIInstruction> CFIInstructions =
C.getMF()->getFrameInstructions();
if (CFICount > 0 && CFICount != CFIInstructions.size())
return std::nullopt;
}
// Returns true if an instructions is safe to fix up, false otherwise.
auto IsSafeToFixup = [this, &TRI](MachineInstr &MI) {
if (MI.isCall())
return true;
if (!MI.modifiesRegister(AArch64::SP, &TRI) &&
!MI.readsRegister(AArch64::SP, &TRI))
return true;
// Any modification of SP will break our code to save/restore LR.
// FIXME: We could handle some instructions which add a constant
// offset to SP, with a bit more work.
if (MI.modifiesRegister(AArch64::SP, &TRI))
return false;
// At this point, we have a stack instruction that we might need to
// fix up. We'll handle it if it's a load or store.
if (MI.mayLoadOrStore()) {
const MachineOperand *Base; // Filled with the base operand of MI.
int64_t Offset; // Filled with the offset of MI.
bool OffsetIsScalable;
// Does it allow us to offset the base operand and is the base the
// register SP?
if (!getMemOperandWithOffset(MI, Base, Offset, OffsetIsScalable, &TRI) ||
!Base->isReg() || Base->getReg() != AArch64::SP)
return false;
// Fixe-up code below assumes bytes.
if (OffsetIsScalable)
return false;
// Find the minimum/maximum offset for this instruction and check
// if fixing it up would be in range.
int64_t MinOffset,
MaxOffset; // Unscaled offsets for the instruction.
// The scale to multiply the offsets by.
TypeSize Scale(0U, false), DummyWidth(0U, false);
getMemOpInfo(MI.getOpcode(), Scale, DummyWidth, MinOffset, MaxOffset);
Offset += 16; // Update the offset to what it would be if we outlined.
if (Offset < MinOffset * (int64_t)Scale.getFixedValue() ||
Offset > MaxOffset * (int64_t)Scale.getFixedValue())
return false;
// It's in range, so we can outline it.
return true;
}
// FIXME: Add handling for instructions like "add x0, sp, #8".
// We can't fix it up, so don't outline it.
return false;
};
// True if it's possible to fix up each stack instruction in this sequence.
// Important for frames/call variants that modify the stack.
bool AllStackInstrsSafe = llvm::all_of(FirstCand, IsSafeToFixup);
// If the last instruction in any candidate is a terminator, then we should
// tail call all of the candidates.
if (RepeatedSequenceLocs[0].back().isTerminator()) {
FrameID = MachineOutlinerTailCall;
NumBytesToCreateFrame = 0;
unsigned NumBytesForCall = 4 + NumBytesToCheckLRInTCEpilogue;
SetCandidateCallInfo(MachineOutlinerTailCall, NumBytesForCall);
}
else if (LastInstrOpcode == AArch64::BL ||
((LastInstrOpcode == AArch64::BLR ||
LastInstrOpcode == AArch64::BLRNoIP) &&
!HasBTI)) {
// FIXME: Do we need to check if the code after this uses the value of LR?
FrameID = MachineOutlinerThunk;
NumBytesToCreateFrame = NumBytesToCheckLRInTCEpilogue;
SetCandidateCallInfo(MachineOutlinerThunk, 4);
}
else {
// We need to decide how to emit calls + frames. We can always emit the same
// frame if we don't need to save to the stack. If we have to save to the
// stack, then we need a different frame.
unsigned NumBytesNoStackCalls = 0;
std::vector<outliner::Candidate> CandidatesWithoutStackFixups;
// Check if we have to save LR.
for (outliner::Candidate &C : RepeatedSequenceLocs) {
bool LRAvailable =
(C.Flags & MachineOutlinerMBBFlags::LRUnavailableSomewhere)
? C.isAvailableAcrossAndOutOfSeq(AArch64::LR, TRI)
: true;
// If we have a noreturn caller, then we're going to be conservative and
// say that we have to save LR. If we don't have a ret at the end of the
// block, then we can't reason about liveness accurately.
//
// FIXME: We can probably do better than always disabling this in
// noreturn functions by fixing up the liveness info.
bool IsNoReturn =
C.getMF()->getFunction().hasFnAttribute(Attribute::NoReturn);
// Is LR available? If so, we don't need a save.
if (LRAvailable && !IsNoReturn) {
NumBytesNoStackCalls += 4;
C.setCallInfo(MachineOutlinerNoLRSave, 4);
CandidatesWithoutStackFixups.push_back(C);
}
// Is an unused register available? If so, we won't modify the stack, so
// we can outline with the same frame type as those that don't save LR.
else if (findRegisterToSaveLRTo(C)) {
NumBytesNoStackCalls += 12;
C.setCallInfo(MachineOutlinerRegSave, 12);
CandidatesWithoutStackFixups.push_back(C);
}
// Is SP used in the sequence at all? If not, we don't have to modify
// the stack, so we are guaranteed to get the same frame.
else if (C.isAvailableInsideSeq(AArch64::SP, TRI)) {
NumBytesNoStackCalls += 12;
C.setCallInfo(MachineOutlinerDefault, 12);
CandidatesWithoutStackFixups.push_back(C);
}
// If we outline this, we need to modify the stack. Pretend we don't
// outline this by saving all of its bytes.
else {
NumBytesNoStackCalls += SequenceSize;
}
}
// If there are no places where we have to save LR, then note that we
// don't have to update the stack. Otherwise, give every candidate the
// default call type, as long as it's safe to do so.
if (!AllStackInstrsSafe ||
NumBytesNoStackCalls <= RepeatedSequenceLocs.size() * 12) {
RepeatedSequenceLocs = CandidatesWithoutStackFixups;
FrameID = MachineOutlinerNoLRSave;
} else {
SetCandidateCallInfo(MachineOutlinerDefault, 12);
// Bugzilla ID: 46767
// TODO: Check if fixing up the stack more than once is safe so we can
// outline these.
//
// An outline resulting in a caller that requires stack fixups at the
// callsite to a callee that also requires stack fixups can happen when
// there are no available registers at the candidate callsite for a
// candidate that itself also has calls.
//
// In other words if function_containing_sequence in the following pseudo
// assembly requires that we save LR at the point of the call, but there
// are no available registers: in this case we save using SP and as a
// result the SP offsets requires stack fixups by multiples of 16.
//
// function_containing_sequence:
// ...
// save LR to SP <- Requires stack instr fixups in OUTLINED_FUNCTION_N
// call OUTLINED_FUNCTION_N
// restore LR from SP
// ...
//
// OUTLINED_FUNCTION_N:
// save LR to SP <- Requires stack instr fixups in OUTLINED_FUNCTION_N
// ...
// bl foo
// restore LR from SP
// ret
//
// Because the code to handle more than one stack fixup does not
// currently have the proper checks for legality, these cases will assert
// in the AArch64 MachineOutliner. This is because the code to do this
// needs more hardening, testing, better checks that generated code is
// legal, etc and because it is only verified to handle a single pass of
// stack fixup.
//
// The assert happens in AArch64InstrInfo::buildOutlinedFrame to catch
// these cases until they are known to be handled. Bugzilla 46767 is
// referenced in comments at the assert site.
//
// To avoid asserting (or generating non-legal code on noassert builds)
// we remove all candidates which would need more than one stack fixup by
// pruning the cases where the candidate has calls while also having no
// available LR and having no available general purpose registers to copy
// LR to (ie one extra stack save/restore).
//
if (FlagsSetInAll & MachineOutlinerMBBFlags::HasCalls) {
erase_if(RepeatedSequenceLocs, [this, &TRI](outliner::Candidate &C) {
auto IsCall = [](const MachineInstr &MI) { return MI.isCall(); };
return (llvm::any_of(C, IsCall)) &&
(!C.isAvailableAcrossAndOutOfSeq(AArch64::LR, TRI) ||
!findRegisterToSaveLRTo(C));
});
}
}
// If we dropped all of the candidates, bail out here.
if (RepeatedSequenceLocs.size() < 2) {
RepeatedSequenceLocs.clear();
return std::nullopt;
}
}
// Does every candidate's MBB contain a call? If so, then we might have a call
// in the range.
if (FlagsSetInAll & MachineOutlinerMBBFlags::HasCalls) {
// Check if the range contains a call. These require a save + restore of the
// link register.
bool ModStackToSaveLR = false;
if (std::any_of(FirstCand.begin(), std::prev(FirstCand.end()),
[](const MachineInstr &MI) { return MI.isCall(); }))
ModStackToSaveLR = true;
// Handle the last instruction separately. If this is a tail call, then the
// last instruction is a call. We don't want to save + restore in this case.
// However, it could be possible that the last instruction is a call without
// it being valid to tail call this sequence. We should consider this as
// well.
else if (FrameID != MachineOutlinerThunk &&
FrameID != MachineOutlinerTailCall && FirstCand.back().isCall())
ModStackToSaveLR = true;
if (ModStackToSaveLR) {
// We can't fix up the stack. Bail out.
if (!AllStackInstrsSafe) {
RepeatedSequenceLocs.clear();
return std::nullopt;
}
// Save + restore LR.
NumBytesToCreateFrame += 8;
}
}
// If we have CFI instructions, we can only outline if the outlined section
// can be a tail call
if (FrameID != MachineOutlinerTailCall && CFICount > 0)
return std::nullopt;
return outliner::OutlinedFunction(RepeatedSequenceLocs, SequenceSize,
NumBytesToCreateFrame, FrameID);
}
void AArch64InstrInfo::mergeOutliningCandidateAttributes(
Function &F, std::vector<outliner::Candidate> &Candidates) const {
// If a bunch of candidates reach this point they must agree on their return
// address signing. It is therefore enough to just consider the signing
// behaviour of one of them
const auto &CFn = Candidates.front().getMF()->getFunction();
// Since all candidates belong to the same module, just copy the
// function-level attributes of an arbitrary function.
if (CFn.hasFnAttribute("sign-return-address"))
F.addFnAttr(CFn.getFnAttribute("sign-return-address"));
if (CFn.hasFnAttribute("sign-return-address-key"))
F.addFnAttr(CFn.getFnAttribute("sign-return-address-key"));
AArch64GenInstrInfo::mergeOutliningCandidateAttributes(F, Candidates);
}
bool AArch64InstrInfo::isFunctionSafeToOutlineFrom(
MachineFunction &MF, bool OutlineFromLinkOnceODRs) const {
const Function &F = MF.getFunction();
// Can F be deduplicated by the linker? If it can, don't outline from it.
if (!OutlineFromLinkOnceODRs && F.hasLinkOnceODRLinkage())
return false;
// Don't outline from functions with section markings; the program could
// expect that all the code is in the named section.
// FIXME: Allow outlining from multiple functions with the same section
// marking.
if (F.hasSection())
return false;
// Outlining from functions with redzones is unsafe since the outliner may
// modify the stack. Check if hasRedZone is true or unknown; if yes, don't
// outline from it.
AArch64FunctionInfo *AFI = MF.getInfo<AArch64FunctionInfo>();
if (!AFI || AFI->hasRedZone().value_or(true))
return false;
// FIXME: Teach the outliner to generate/handle Windows unwind info.
if (MF.getTarget().getMCAsmInfo()->usesWindowsCFI())
return false;
// It's safe to outline from MF.
return true;
}
SmallVector<std::pair<MachineBasicBlock::iterator, MachineBasicBlock::iterator>>
AArch64InstrInfo::getOutlinableRanges(MachineBasicBlock &MBB,
unsigned &Flags) const {
assert(MBB.getParent()->getRegInfo().tracksLiveness() &&
"Must track liveness!");
SmallVector<
std::pair<MachineBasicBlock::iterator, MachineBasicBlock::iterator>>
Ranges;
// According to the AArch64 Procedure Call Standard, the following are
// undefined on entry/exit from a function call:
//
// * Registers x16, x17, (and thus w16, w17)
// * Condition codes (and thus the NZCV register)
//
// If any of these registers are used inside or live across an outlined
// function, then they may be modified later, either by the compiler or
// some other tool (like the linker).
//
// To avoid outlining in these situations, partition each block into ranges
// where these registers are dead. We will only outline from those ranges.
LiveRegUnits LRU(getRegisterInfo());
auto AreAllUnsafeRegsDead = [&LRU]() {
return LRU.available(AArch64::W16) && LRU.available(AArch64::W17) &&
LRU.available(AArch64::NZCV);
};
// We need to know if LR is live across an outlining boundary later on in
// order to decide how we'll create the outlined call, frame, etc.
//
// It's pretty expensive to check this for *every candidate* within a block.
// That's some potentially n^2 behaviour, since in the worst case, we'd need
// to compute liveness from the end of the block for O(n) candidates within
// the block.
//
// So, to improve the average case, let's keep track of liveness from the end
// of the block to the beginning of *every outlinable range*. If we know that
// LR is available in every range we could outline from, then we know that
// we don't need to check liveness for any candidate within that range.
bool LRAvailableEverywhere = true;
// Compute liveness bottom-up.
LRU.addLiveOuts(MBB);
// Update flags that require info about the entire MBB.
auto UpdateWholeMBBFlags = [&Flags](const MachineInstr &MI) {
if (MI.isCall() && !MI.isTerminator())
Flags |= MachineOutlinerMBBFlags::HasCalls;
};
// Range: [RangeBegin, RangeEnd)
MachineBasicBlock::instr_iterator RangeBegin, RangeEnd;
unsigned RangeLen;
auto CreateNewRangeStartingAt =
[&RangeBegin, &RangeEnd,
&RangeLen](MachineBasicBlock::instr_iterator NewBegin) {
RangeBegin = NewBegin;
RangeEnd = std::next(RangeBegin);
RangeLen = 0;
};
auto SaveRangeIfNonEmpty = [&RangeLen, &Ranges, &RangeBegin, &RangeEnd]() {
// At least one unsafe register is not dead. We do not want to outline at
// this point. If it is long enough to outline from, save the range
// [RangeBegin, RangeEnd).
if (RangeLen > 1)
Ranges.push_back(std::make_pair(RangeBegin, RangeEnd));
};
// Find the first point where all unsafe registers are dead.
// FIND: <safe instr> <-- end of first potential range
// SKIP: <unsafe def>
// SKIP: ... everything between ...
// SKIP: <unsafe use>
auto FirstPossibleEndPt = MBB.instr_rbegin();
for (; FirstPossibleEndPt != MBB.instr_rend(); ++FirstPossibleEndPt) {
LRU.stepBackward(*FirstPossibleEndPt);
// Update flags that impact how we outline across the entire block,
// regardless of safety.
UpdateWholeMBBFlags(*FirstPossibleEndPt);
if (AreAllUnsafeRegsDead())
break;
}
// If we exhausted the entire block, we have no safe ranges to outline.
if (FirstPossibleEndPt == MBB.instr_rend())
return Ranges;
// Current range.
CreateNewRangeStartingAt(FirstPossibleEndPt->getIterator());
// StartPt points to the first place where all unsafe registers
// are dead (if there is any such point). Begin partitioning the MBB into
// ranges.
for (auto &MI : make_range(FirstPossibleEndPt, MBB.instr_rend())) {
LRU.stepBackward(MI);
UpdateWholeMBBFlags(MI);
if (!AreAllUnsafeRegsDead()) {
SaveRangeIfNonEmpty();
CreateNewRangeStartingAt(MI.getIterator());
continue;
}
LRAvailableEverywhere &= LRU.available(AArch64::LR);
RangeBegin = MI.getIterator();
++RangeLen;
}
// Above loop misses the last (or only) range. If we are still safe, then
// let's save the range.
if (AreAllUnsafeRegsDead())
SaveRangeIfNonEmpty();
if (Ranges.empty())
return Ranges;
// We found the ranges bottom-up. Mapping expects the top-down. Reverse
// the order.
std::reverse(Ranges.begin(), Ranges.end());
// If there is at least one outlinable range where LR is unavailable
// somewhere, remember that.
if (!LRAvailableEverywhere)
Flags |= MachineOutlinerMBBFlags::LRUnavailableSomewhere;
return Ranges;
}
outliner::InstrType
AArch64InstrInfo::getOutliningTypeImpl(MachineBasicBlock::iterator &MIT,
unsigned Flags) const {
MachineInstr &MI = *MIT;
MachineBasicBlock *MBB = MI.getParent();
MachineFunction *MF = MBB->getParent();
AArch64FunctionInfo *FuncInfo = MF->getInfo<AArch64FunctionInfo>();
// Don't outline anything used for return address signing. The outlined
// function will get signed later if needed
switch (MI.getOpcode()) {
case AArch64::PACM:
case AArch64::PACIASP:
case AArch64::PACIBSP:
case AArch64::PACIASPPC:
case AArch64::PACIBSPPC:
case AArch64::AUTIASP:
case AArch64::AUTIBSP:
case AArch64::AUTIASPPCi:
case AArch64::AUTIASPPCr:
case AArch64::AUTIBSPPCi:
case AArch64::AUTIBSPPCr:
case AArch64::RETAA:
case AArch64::RETAB:
case AArch64::RETAASPPCi:
case AArch64::RETAASPPCr:
case AArch64::RETABSPPCi:
case AArch64::RETABSPPCr:
case AArch64::EMITBKEY:
case AArch64::PAUTH_PROLOGUE:
case AArch64::PAUTH_EPILOGUE:
return outliner::InstrType::Illegal;
}
// Don't outline LOHs.
if (FuncInfo->getLOHRelated().count(&MI))
return outliner::InstrType::Illegal;
// We can only outline these if we will tail call the outlined function, or
// fix up the CFI offsets. Currently, CFI instructions are outlined only if
// in a tail call.
//
// FIXME: If the proper fixups for the offset are implemented, this should be
// possible.
if (MI.isCFIInstruction())
return outliner::InstrType::Legal;
// Is this a terminator for a basic block?
if (MI.isTerminator())
// TargetInstrInfo::getOutliningType has already filtered out anything
// that would break this, so we can allow it here.
return outliner::InstrType::Legal;
// Make sure none of the operands are un-outlinable.
for (const MachineOperand &MOP : MI.operands()) {
// A check preventing CFI indices was here before, but only CFI
// instructions should have those.
assert(!MOP.isCFIIndex());
// If it uses LR or W30 explicitly, then don't touch it.
if (MOP.isReg() && !MOP.isImplicit() &&
(MOP.getReg() == AArch64::LR || MOP.getReg() == AArch64::W30))
return outliner::InstrType::Illegal;
}
// Special cases for instructions that can always be outlined, but will fail
// the later tests. e.g, ADRPs, which are PC-relative use LR, but can always
// be outlined because they don't require a *specific* value to be in LR.
if (MI.getOpcode() == AArch64::ADRP)
return outliner::InstrType::Legal;
// If MI is a call we might be able to outline it. We don't want to outline
// any calls that rely on the position of items on the stack. When we outline
// something containing a call, we have to emit a save and restore of LR in
// the outlined function. Currently, this always happens by saving LR to the
// stack. Thus, if we outline, say, half the parameters for a function call
// plus the call, then we'll break the callee's expectations for the layout
// of the stack.
//
// FIXME: Allow calls to functions which construct a stack frame, as long
// as they don't access arguments on the stack.
// FIXME: Figure out some way to analyze functions defined in other modules.
// We should be able to compute the memory usage based on the IR calling
// convention, even if we can't see the definition.
if (MI.isCall()) {
// Get the function associated with the call. Look at each operand and find
// the one that represents the callee and get its name.
const Function *Callee = nullptr;
for (const MachineOperand &MOP : MI.operands()) {
if (MOP.isGlobal()) {
Callee = dyn_cast<Function>(MOP.getGlobal());
break;
}
}
// Never outline calls to mcount. There isn't any rule that would require
// this, but the Linux kernel's "ftrace" feature depends on it.
if (Callee && Callee->getName() == "\01_mcount")
return outliner::InstrType::Illegal;
// If we don't know anything about the callee, assume it depends on the
// stack layout of the caller. In that case, it's only legal to outline
// as a tail-call. Explicitly list the call instructions we know about so we
// don't get unexpected results with call pseudo-instructions.
auto UnknownCallOutlineType = outliner::InstrType::Illegal;
if (MI.getOpcode() == AArch64::BLR ||
MI.getOpcode() == AArch64::BLRNoIP || MI.getOpcode() == AArch64::BL)
UnknownCallOutlineType = outliner::InstrType::LegalTerminator;
if (!Callee)
return UnknownCallOutlineType;
// We have a function we have information about. Check it if it's something
// can safely outline.
MachineFunction *CalleeMF = MF->getMMI().getMachineFunction(*Callee);
// We don't know what's going on with the callee at all. Don't touch it.
if (!CalleeMF)
return UnknownCallOutlineType;
// Check if we know anything about the callee saves on the function. If we
// don't, then don't touch it, since that implies that we haven't
// computed anything about its stack frame yet.
MachineFrameInfo &MFI = CalleeMF->getFrameInfo();
if (!MFI.isCalleeSavedInfoValid() || MFI.getStackSize() > 0 ||
MFI.getNumObjects() > 0)
return UnknownCallOutlineType;
// At this point, we can say that CalleeMF ought to not pass anything on the
// stack. Therefore, we can outline it.
return outliner::InstrType::Legal;
}
// Don't touch the link register or W30.
if (MI.readsRegister(AArch64::W30, &getRegisterInfo()) ||
MI.modifiesRegister(AArch64::W30, &getRegisterInfo()))
return outliner::InstrType::Illegal;
// Don't outline BTI instructions, because that will prevent the outlining
// site from being indirectly callable.
if (hasBTISemantics(MI))
return outliner::InstrType::Illegal;
return outliner::InstrType::Legal;
}
void AArch64InstrInfo::fixupPostOutline(MachineBasicBlock &MBB) const {
for (MachineInstr &MI : MBB) {
const MachineOperand *Base;
TypeSize Width(0, false);
int64_t Offset;
bool OffsetIsScalable;
// Is this a load or store with an immediate offset with SP as the base?
if (!MI.mayLoadOrStore() ||
!getMemOperandWithOffsetWidth(MI, Base, Offset, OffsetIsScalable, Width,
&RI) ||
(Base->isReg() && Base->getReg() != AArch64::SP))
continue;
// It is, so we have to fix it up.
TypeSize Scale(0U, false);
int64_t Dummy1, Dummy2;
MachineOperand &StackOffsetOperand = getMemOpBaseRegImmOfsOffsetOperand(MI);
assert(StackOffsetOperand.isImm() && "Stack offset wasn't immediate!");
getMemOpInfo(MI.getOpcode(), Scale, Width, Dummy1, Dummy2);
assert(Scale != 0 && "Unexpected opcode!");
assert(!OffsetIsScalable && "Expected offset to be a byte offset");
// We've pushed the return address to the stack, so add 16 to the offset.
// This is safe, since we already checked if it would overflow when we
// checked if this instruction was legal to outline.
int64_t NewImm = (Offset + 16) / (int64_t)Scale.getFixedValue();
StackOffsetOperand.setImm(NewImm);
}
}
static void signOutlinedFunction(MachineFunction &MF, MachineBasicBlock &MBB,
const AArch64InstrInfo *TII,
bool ShouldSignReturnAddr) {
if (!ShouldSignReturnAddr)
return;
BuildMI(MBB, MBB.begin(), DebugLoc(), TII->get(AArch64::PAUTH_PROLOGUE))
.setMIFlag(MachineInstr::FrameSetup);
BuildMI(MBB, MBB.getFirstInstrTerminator(), DebugLoc(),
TII->get(AArch64::PAUTH_EPILOGUE))
.setMIFlag(MachineInstr::FrameDestroy);
}
void AArch64InstrInfo::buildOutlinedFrame(
MachineBasicBlock &MBB, MachineFunction &MF,
const outliner::OutlinedFunction &OF) const {
AArch64FunctionInfo *FI = MF.getInfo<AArch64FunctionInfo>();
if (OF.FrameConstructionID == MachineOutlinerTailCall)
FI->setOutliningStyle("Tail Call");
else if (OF.FrameConstructionID == MachineOutlinerThunk) {
// For thunk outlining, rewrite the last instruction from a call to a
// tail-call.
MachineInstr *Call = &*--MBB.instr_end();
unsigned TailOpcode;
if (Call->getOpcode() == AArch64::BL) {
TailOpcode = AArch64::TCRETURNdi;
} else {
assert(Call->getOpcode() == AArch64::BLR ||
Call->getOpcode() == AArch64::BLRNoIP);
TailOpcode = AArch64::TCRETURNriALL;
}
MachineInstr *TC = BuildMI(MF, DebugLoc(), get(TailOpcode))
.add(Call->getOperand(0))
.addImm(0);
MBB.insert(MBB.end(), TC);
Call->eraseFromParent();
FI->setOutliningStyle("Thunk");
}
bool IsLeafFunction = true;
// Is there a call in the outlined range?
auto IsNonTailCall = [](const MachineInstr &MI) {
return MI.isCall() && !MI.isReturn();
};
if (llvm::any_of(MBB.instrs(), IsNonTailCall)) {
// Fix up the instructions in the range, since we're going to modify the
// stack.
// Bugzilla ID: 46767
// TODO: Check if fixing up twice is safe so we can outline these.
assert(OF.FrameConstructionID != MachineOutlinerDefault &&
"Can only fix up stack references once");
fixupPostOutline(MBB);
IsLeafFunction = false;
// LR has to be a live in so that we can save it.
if (!MBB.isLiveIn(AArch64::LR))
MBB.addLiveIn(AArch64::LR);
MachineBasicBlock::iterator It = MBB.begin();
MachineBasicBlock::iterator Et = MBB.end();
if (OF.FrameConstructionID == MachineOutlinerTailCall ||
OF.FrameConstructionID == MachineOutlinerThunk)
Et = std::prev(MBB.end());
// Insert a save before the outlined region
MachineInstr *STRXpre = BuildMI(MF, DebugLoc(), get(AArch64::STRXpre))
.addReg(AArch64::SP, RegState::Define)
.addReg(AArch64::LR)
.addReg(AArch64::SP)
.addImm(-16);
It = MBB.insert(It, STRXpre);
if (MF.getInfo<AArch64FunctionInfo>()->needsDwarfUnwindInfo(MF)) {
const TargetSubtargetInfo &STI = MF.getSubtarget();
const MCRegisterInfo *MRI = STI.getRegisterInfo();
unsigned DwarfReg = MRI->getDwarfRegNum(AArch64::LR, true);
// Add a CFI saying the stack was moved 16 B down.
int64_t StackPosEntry =
MF.addFrameInst(MCCFIInstruction::cfiDefCfaOffset(nullptr, 16));
BuildMI(MBB, It, DebugLoc(), get(AArch64::CFI_INSTRUCTION))
.addCFIIndex(StackPosEntry)
.setMIFlags(MachineInstr::FrameSetup);
// Add a CFI saying that the LR that we want to find is now 16 B higher
// than before.
int64_t LRPosEntry = MF.addFrameInst(
MCCFIInstruction::createOffset(nullptr, DwarfReg, -16));
BuildMI(MBB, It, DebugLoc(), get(AArch64::CFI_INSTRUCTION))
.addCFIIndex(LRPosEntry)
.setMIFlags(MachineInstr::FrameSetup);
}
// Insert a restore before the terminator for the function.
MachineInstr *LDRXpost = BuildMI(MF, DebugLoc(), get(AArch64::LDRXpost))
.addReg(AArch64::SP, RegState::Define)
.addReg(AArch64::LR, RegState::Define)
.addReg(AArch64::SP)
.addImm(16);
Et = MBB.insert(Et, LDRXpost);
}
bool ShouldSignReturnAddr = FI->shouldSignReturnAddress(!IsLeafFunction);
// If this is a tail call outlined function, then there's already a return.
if (OF.FrameConstructionID == MachineOutlinerTailCall ||
OF.FrameConstructionID == MachineOutlinerThunk) {
signOutlinedFunction(MF, MBB, this, ShouldSignReturnAddr);
return;
}
// It's not a tail call, so we have to insert the return ourselves.
// LR has to be a live in so that we can return to it.
if (!MBB.isLiveIn(AArch64::LR))
MBB.addLiveIn(AArch64::LR);
MachineInstr *ret = BuildMI(MF, DebugLoc(), get(AArch64::RET))
.addReg(AArch64::LR);
MBB.insert(MBB.end(), ret);
signOutlinedFunction(MF, MBB, this, ShouldSignReturnAddr);
FI->setOutliningStyle("Function");
// Did we have to modify the stack by saving the link register?
if (OF.FrameConstructionID != MachineOutlinerDefault)
return;
// We modified the stack.
// Walk over the basic block and fix up all the stack accesses.
fixupPostOutline(MBB);
}
MachineBasicBlock::iterator AArch64InstrInfo::insertOutlinedCall(
Module &M, MachineBasicBlock &MBB, MachineBasicBlock::iterator &It,
MachineFunction &MF, outliner::Candidate &C) const {
// Are we tail calling?
if (C.CallConstructionID == MachineOutlinerTailCall) {
// If yes, then we can just branch to the label.
It = MBB.insert(It, BuildMI(MF, DebugLoc(), get(AArch64::TCRETURNdi))
.addGlobalAddress(M.getNamedValue(MF.getName()))
.addImm(0));
return It;
}
// Are we saving the link register?
if (C.CallConstructionID == MachineOutlinerNoLRSave ||
C.CallConstructionID == MachineOutlinerThunk) {
// No, so just insert the call.
It = MBB.insert(It, BuildMI(MF, DebugLoc(), get(AArch64::BL))
.addGlobalAddress(M.getNamedValue(MF.getName())));
return It;
}
// We want to return the spot where we inserted the call.
MachineBasicBlock::iterator CallPt;
// Instructions for saving and restoring LR around the call instruction we're
// going to insert.
MachineInstr *Save;
MachineInstr *Restore;
// Can we save to a register?
if (C.CallConstructionID == MachineOutlinerRegSave) {
// FIXME: This logic should be sunk into a target-specific interface so that
// we don't have to recompute the register.
Register Reg = findRegisterToSaveLRTo(C);
assert(Reg && "No callee-saved register available?");
// LR has to be a live in so that we can save it.
if (!MBB.isLiveIn(AArch64::LR))
MBB.addLiveIn(AArch64::LR);
// Save and restore LR from Reg.
Save = BuildMI(MF, DebugLoc(), get(AArch64::ORRXrs), Reg)
.addReg(AArch64::XZR)
.addReg(AArch64::LR)
.addImm(0);
Restore = BuildMI(MF, DebugLoc(), get(AArch64::ORRXrs), AArch64::LR)
.addReg(AArch64::XZR)
.addReg(Reg)
.addImm(0);
} else {
// We have the default case. Save and restore from SP.
Save = BuildMI(MF, DebugLoc(), get(AArch64::STRXpre))
.addReg(AArch64::SP, RegState::Define)
.addReg(AArch64::LR)
.addReg(AArch64::SP)
.addImm(-16);
Restore = BuildMI(MF, DebugLoc(), get(AArch64::LDRXpost))
.addReg(AArch64::SP, RegState::Define)
.addReg(AArch64::LR, RegState::Define)
.addReg(AArch64::SP)
.addImm(16);
}
It = MBB.insert(It, Save);
It++;
// Insert the call.
It = MBB.insert(It, BuildMI(MF, DebugLoc(), get(AArch64::BL))
.addGlobalAddress(M.getNamedValue(MF.getName())));
CallPt = It;
It++;
It = MBB.insert(It, Restore);
return CallPt;
}
bool AArch64InstrInfo::shouldOutlineFromFunctionByDefault(
MachineFunction &MF) const {
return MF.getFunction().hasMinSize();
}
void AArch64InstrInfo::buildClearRegister(Register Reg, MachineBasicBlock &MBB,
MachineBasicBlock::iterator Iter,
DebugLoc &DL,
bool AllowSideEffects) const {
const MachineFunction &MF = *MBB.getParent();
const AArch64Subtarget &STI = MF.getSubtarget<AArch64Subtarget>();
const AArch64RegisterInfo &TRI = *STI.getRegisterInfo();
if (TRI.isGeneralPurposeRegister(MF, Reg)) {
BuildMI(MBB, Iter, DL, get(AArch64::MOVZXi), Reg).addImm(0).addImm(0);
} else if (STI.hasSVE()) {
BuildMI(MBB, Iter, DL, get(AArch64::DUP_ZI_D), Reg)
.addImm(0)
.addImm(0);
} else {
BuildMI(MBB, Iter, DL, get(AArch64::MOVIv2d_ns), Reg)
.addImm(0);
}
}
std::optional<DestSourcePair>
AArch64InstrInfo::isCopyInstrImpl(const MachineInstr &MI) const {
// AArch64::ORRWrs and AArch64::ORRXrs with WZR/XZR reg
// and zero immediate operands used as an alias for mov instruction.
if (MI.getOpcode() == AArch64::ORRWrs &&
MI.getOperand(1).getReg() == AArch64::WZR &&
MI.getOperand(3).getImm() == 0x0 &&
// Check that the w->w move is not a zero-extending w->x mov.
(!MI.getOperand(0).getReg().isVirtual() ||
MI.getOperand(0).getSubReg() == 0) &&
(!MI.getOperand(0).getReg().isPhysical() ||
MI.findRegisterDefOperandIdx(MI.getOperand(0).getReg() - AArch64::W0 +
AArch64::X0,
/*TRI=*/nullptr) == -1))
return DestSourcePair{MI.getOperand(0), MI.getOperand(2)};
if (MI.getOpcode() == AArch64::ORRXrs &&
MI.getOperand(1).getReg() == AArch64::XZR &&
MI.getOperand(3).getImm() == 0x0)
return DestSourcePair{MI.getOperand(0), MI.getOperand(2)};
return std::nullopt;
}
std::optional<DestSourcePair>
AArch64InstrInfo::isCopyLikeInstrImpl(const MachineInstr &MI) const {
if (MI.getOpcode() == AArch64::ORRWrs &&
MI.getOperand(1).getReg() == AArch64::WZR &&
MI.getOperand(3).getImm() == 0x0)
return DestSourcePair{MI.getOperand(0), MI.getOperand(2)};
return std::nullopt;
}
std::optional<RegImmPair>
AArch64InstrInfo::isAddImmediate(const MachineInstr &MI, Register Reg) const {
int Sign = 1;
int64_t Offset = 0;
// TODO: Handle cases where Reg is a super- or sub-register of the
// destination register.
const MachineOperand &Op0 = MI.getOperand(0);
if (!Op0.isReg() || Reg != Op0.getReg())
return std::nullopt;
switch (MI.getOpcode()) {
default:
return std::nullopt;
case AArch64::SUBWri:
case AArch64::SUBXri:
case AArch64::SUBSWri:
case AArch64::SUBSXri:
Sign *= -1;
[[fallthrough]];
case AArch64::ADDSWri:
case AArch64::ADDSXri:
case AArch64::ADDWri:
case AArch64::ADDXri: {
// TODO: Third operand can be global address (usually some string).
if (!MI.getOperand(0).isReg() || !MI.getOperand(1).isReg() ||
!MI.getOperand(2).isImm())
return std::nullopt;
int Shift = MI.getOperand(3).getImm();
assert((Shift == 0 || Shift == 12) && "Shift can be either 0 or 12");
Offset = Sign * (MI.getOperand(2).getImm() << Shift);
}
}
return RegImmPair{MI.getOperand(1).getReg(), Offset};
}
/// If the given ORR instruction is a copy, and \p DescribedReg overlaps with
/// the destination register then, if possible, describe the value in terms of
/// the source register.
static std::optional<ParamLoadedValue>
describeORRLoadedValue(const MachineInstr &MI, Register DescribedReg,
const TargetInstrInfo *TII,
const TargetRegisterInfo *TRI) {
auto DestSrc = TII->isCopyLikeInstr(MI);
if (!DestSrc)
return std::nullopt;
Register DestReg = DestSrc->Destination->getReg();
Register SrcReg = DestSrc->Source->getReg();
auto Expr = DIExpression::get(MI.getMF()->getFunction().getContext(), {});
// If the described register is the destination, just return the source.
if (DestReg == DescribedReg)
return ParamLoadedValue(MachineOperand::CreateReg(SrcReg, false), Expr);
// ORRWrs zero-extends to 64-bits, so we need to consider such cases.
if (MI.getOpcode() == AArch64::ORRWrs &&
TRI->isSuperRegister(DestReg, DescribedReg))
return ParamLoadedValue(MachineOperand::CreateReg(SrcReg, false), Expr);
// We may need to describe the lower part of a ORRXrs move.
if (MI.getOpcode() == AArch64::ORRXrs &&
TRI->isSubRegister(DestReg, DescribedReg)) {
Register SrcSubReg = TRI->getSubReg(SrcReg, AArch64::sub_32);
return ParamLoadedValue(MachineOperand::CreateReg(SrcSubReg, false), Expr);
}
assert(!TRI->isSuperOrSubRegisterEq(DestReg, DescribedReg) &&
"Unhandled ORR[XW]rs copy case");
return std::nullopt;
}
bool AArch64InstrInfo::isFunctionSafeToSplit(const MachineFunction &MF) const {
// Functions cannot be split to different sections on AArch64 if they have
// a red zone. This is because relaxing a cross-section branch may require
// incrementing the stack pointer to spill a register, which would overwrite
// the red zone.
if (MF.getInfo<AArch64FunctionInfo>()->hasRedZone().value_or(true))
return false;
return TargetInstrInfo::isFunctionSafeToSplit(MF);
}
bool AArch64InstrInfo::isMBBSafeToSplitToCold(
const MachineBasicBlock &MBB) const {
// Asm Goto blocks can contain conditional branches to goto labels, which can
// get moved out of range of the branch instruction.
auto isAsmGoto = [](const MachineInstr &MI) {
return MI.getOpcode() == AArch64::INLINEASM_BR;
};
if (llvm::any_of(MBB, isAsmGoto) || MBB.isInlineAsmBrIndirectTarget())
return false;
// Because jump tables are label-relative instead of table-relative, they all
// must be in the same section or relocation fixup handling will fail.
// Check if MBB is a jump table target
const MachineJumpTableInfo *MJTI = MBB.getParent()->getJumpTableInfo();
auto containsMBB = [&MBB](const MachineJumpTableEntry &JTE) {
return llvm::is_contained(JTE.MBBs, &MBB);
};
if (MJTI != nullptr && llvm::any_of(MJTI->getJumpTables(), containsMBB))
return false;
// Check if MBB contains a jump table lookup
for (const MachineInstr &MI : MBB) {
switch (MI.getOpcode()) {
case TargetOpcode::G_BRJT:
case AArch64::JumpTableDest32:
case AArch64::JumpTableDest16:
case AArch64::JumpTableDest8:
return false;
default:
continue;
}
}
// MBB isn't a special case, so it's safe to be split to the cold section.
return true;
}
std::optional<ParamLoadedValue>
AArch64InstrInfo::describeLoadedValue(const MachineInstr &MI,
Register Reg) const {
const MachineFunction *MF = MI.getMF();
const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
switch (MI.getOpcode()) {
case AArch64::MOVZWi:
case AArch64::MOVZXi: {
// MOVZWi may be used for producing zero-extended 32-bit immediates in
// 64-bit parameters, so we need to consider super-registers.
if (!TRI->isSuperRegisterEq(MI.getOperand(0).getReg(), Reg))
return std::nullopt;
if (!MI.getOperand(1).isImm())
return std::nullopt;
int64_t Immediate = MI.getOperand(1).getImm();
int Shift = MI.getOperand(2).getImm();
return ParamLoadedValue(MachineOperand::CreateImm(Immediate << Shift),
nullptr);
}
case AArch64::ORRWrs:
case AArch64::ORRXrs:
return describeORRLoadedValue(MI, Reg, this, TRI);
}
return TargetInstrInfo::describeLoadedValue(MI, Reg);
}
bool AArch64InstrInfo::isExtendLikelyToBeFolded(
MachineInstr &ExtMI, MachineRegisterInfo &MRI) const {
assert(ExtMI.getOpcode() == TargetOpcode::G_SEXT ||
ExtMI.getOpcode() == TargetOpcode::G_ZEXT ||
ExtMI.getOpcode() == TargetOpcode::G_ANYEXT);
// Anyexts are nops.
if (ExtMI.getOpcode() == TargetOpcode::G_ANYEXT)
return true;
Register DefReg = ExtMI.getOperand(0).getReg();
if (!MRI.hasOneNonDBGUse(DefReg))
return false;
// It's likely that a sext/zext as a G_PTR_ADD offset will be folded into an
// addressing mode.
auto *UserMI = &*MRI.use_instr_nodbg_begin(DefReg);
return UserMI->getOpcode() == TargetOpcode::G_PTR_ADD;
}
uint64_t AArch64InstrInfo::getElementSizeForOpcode(unsigned Opc) const {
return get(Opc).TSFlags & AArch64::ElementSizeMask;
}
bool AArch64InstrInfo::isPTestLikeOpcode(unsigned Opc) const {
return get(Opc).TSFlags & AArch64::InstrFlagIsPTestLike;
}
bool AArch64InstrInfo::isWhileOpcode(unsigned Opc) const {
return get(Opc).TSFlags & AArch64::InstrFlagIsWhile;
}
unsigned int
AArch64InstrInfo::getTailDuplicateSize(CodeGenOptLevel OptLevel) const {
return OptLevel >= CodeGenOptLevel::Aggressive ? 6 : 2;
}
bool AArch64InstrInfo::isLegalAddressingMode(unsigned NumBytes, int64_t Offset,
unsigned Scale) const {
if (Offset && Scale)
return false;
// Check Reg + Imm
if (!Scale) {
// 9-bit signed offset
if (isInt<9>(Offset))
return true;
// 12-bit unsigned offset
unsigned Shift = Log2_64(NumBytes);
if (NumBytes && Offset > 0 && (Offset / NumBytes) <= (1LL << 12) - 1 &&
// Must be a multiple of NumBytes (NumBytes is a power of 2)
(Offset >> Shift) << Shift == Offset)
return true;
return false;
}
// Check reg1 + SIZE_IN_BYTES * reg2 and reg1 + reg2
return Scale == 1 || (Scale > 0 && Scale == NumBytes);
}
unsigned llvm::getBLRCallOpcode(const MachineFunction &MF) {
if (MF.getSubtarget<AArch64Subtarget>().hardenSlsBlr())
return AArch64::BLRNoIP;
else
return AArch64::BLR;
}
MachineBasicBlock::iterator
AArch64InstrInfo::probedStackAlloc(MachineBasicBlock::iterator MBBI,
Register TargetReg, bool FrameSetup) const {
assert(TargetReg != AArch64::SP && "New top of stack cannot aleady be in SP");
MachineBasicBlock &MBB = *MBBI->getParent();
MachineFunction &MF = *MBB.getParent();
const AArch64InstrInfo *TII =
MF.getSubtarget<AArch64Subtarget>().getInstrInfo();
int64_t ProbeSize = MF.getInfo<AArch64FunctionInfo>()->getStackProbeSize();
DebugLoc DL = MBB.findDebugLoc(MBBI);
MachineFunction::iterator MBBInsertPoint = std::next(MBB.getIterator());
MachineBasicBlock *LoopTestMBB =
MF.CreateMachineBasicBlock(MBB.getBasicBlock());
MF.insert(MBBInsertPoint, LoopTestMBB);
MachineBasicBlock *LoopBodyMBB =
MF.CreateMachineBasicBlock(MBB.getBasicBlock());
MF.insert(MBBInsertPoint, LoopBodyMBB);
MachineBasicBlock *ExitMBB = MF.CreateMachineBasicBlock(MBB.getBasicBlock());
MF.insert(MBBInsertPoint, ExitMBB);
MachineInstr::MIFlag Flags =
FrameSetup ? MachineInstr::FrameSetup : MachineInstr::NoFlags;
// LoopTest:
// SUB SP, SP, #ProbeSize
emitFrameOffset(*LoopTestMBB, LoopTestMBB->end(), DL, AArch64::SP,
AArch64::SP, StackOffset::getFixed(-ProbeSize), TII, Flags);
// CMP SP, TargetReg
BuildMI(*LoopTestMBB, LoopTestMBB->end(), DL, TII->get(AArch64::SUBSXrx64),
AArch64::XZR)
.addReg(AArch64::SP)
.addReg(TargetReg)
.addImm(AArch64_AM::getArithExtendImm(AArch64_AM::UXTX, 0))
.setMIFlags(Flags);
// B.<Cond> LoopExit
BuildMI(*LoopTestMBB, LoopTestMBB->end(), DL, TII->get(AArch64::Bcc))
.addImm(AArch64CC::LE)
.addMBB(ExitMBB)
.setMIFlags(Flags);
// STR XZR, [SP]
BuildMI(*LoopBodyMBB, LoopBodyMBB->end(), DL, TII->get(AArch64::STRXui))
.addReg(AArch64::XZR)
.addReg(AArch64::SP)
.addImm(0)
.setMIFlags(Flags);
// B loop
BuildMI(*LoopBodyMBB, LoopBodyMBB->end(), DL, TII->get(AArch64::B))
.addMBB(LoopTestMBB)
.setMIFlags(Flags);
// LoopExit:
// MOV SP, TargetReg
BuildMI(*ExitMBB, ExitMBB->end(), DL, TII->get(AArch64::ADDXri), AArch64::SP)
.addReg(TargetReg)
.addImm(0)
.addImm(AArch64_AM::getShifterImm(AArch64_AM::LSL, 0))
.setMIFlags(Flags);
// LDR XZR, [SP]
BuildMI(*ExitMBB, ExitMBB->end(), DL, TII->get(AArch64::LDRXui))
.addReg(AArch64::XZR, RegState::Define)
.addReg(AArch64::SP)
.addImm(0)
.setMIFlags(Flags);
ExitMBB->splice(ExitMBB->end(), &MBB, std::next(MBBI), MBB.end());
ExitMBB->transferSuccessorsAndUpdatePHIs(&MBB);
LoopTestMBB->addSuccessor(ExitMBB);
LoopTestMBB->addSuccessor(LoopBodyMBB);
LoopBodyMBB->addSuccessor(LoopTestMBB);
MBB.addSuccessor(LoopTestMBB);
// Update liveins.
if (MF.getRegInfo().reservedRegsFrozen())
fullyRecomputeLiveIns({ExitMBB, LoopBodyMBB, LoopTestMBB});
return ExitMBB->begin();
}
namespace {
class AArch64PipelinerLoopInfo : public TargetInstrInfo::PipelinerLoopInfo {
MachineInstr *PredBranch;
SmallVector<MachineOperand, 4> Cond;
public:
AArch64PipelinerLoopInfo(MachineInstr *PredBranch,
const SmallVectorImpl<MachineOperand> &Cond)
: PredBranch(PredBranch), Cond(Cond.begin(), Cond.end()) {}
bool shouldIgnoreForPipelining(const MachineInstr *MI) const override {
// Make the instructions for loop control be placed in stage 0.
// The predecessors of PredBranch are considered by the caller.
return MI == PredBranch;
}
std::optional<bool> createTripCountGreaterCondition(
int TC, MachineBasicBlock &MBB,
SmallVectorImpl<MachineOperand> &CondParam) override {
// A branch instruction will be inserted as "if (Cond) goto epilogue".
// Cond is normalized for such use.
// The predecessors of the branch are assumed to have already been inserted.
CondParam = Cond;
return {};
}
void setPreheader(MachineBasicBlock *NewPreheader) override {}
void adjustTripCount(int TripCountAdjust) override {}
void disposed() override {}
};
} // namespace
static bool isCompareAndBranch(unsigned Opcode) {
switch (Opcode) {
case AArch64::CBZW:
case AArch64::CBZX:
case AArch64::CBNZW:
case AArch64::CBNZX:
case AArch64::TBZW:
case AArch64::TBZX:
case AArch64::TBNZW:
case AArch64::TBNZX:
return true;
}
return false;
}
std::unique_ptr<TargetInstrInfo::PipelinerLoopInfo>
AArch64InstrInfo::analyzeLoopForPipelining(MachineBasicBlock *LoopBB) const {
MachineBasicBlock *TBB = nullptr, *FBB = nullptr;
SmallVector<MachineOperand, 4> Cond;
if (analyzeBranch(*LoopBB, TBB, FBB, Cond))
return nullptr;
// Infinite loops are not supported
if (TBB == LoopBB && FBB == LoopBB)
return nullptr;
// Must be conditional branch
if (FBB == nullptr)
return nullptr;
assert((TBB == LoopBB || FBB == LoopBB) &&
"The Loop must be a single-basic-block loop");
// Normalization for createTripCountGreaterCondition()
if (TBB == LoopBB)
reverseBranchCondition(Cond);
MachineInstr *CondBranch = &*LoopBB->getFirstTerminator();
const TargetRegisterInfo &TRI = getRegisterInfo();
// Find the immediate predecessor of the conditional branch
MachineInstr *PredBranch = nullptr;
if (CondBranch->getOpcode() == AArch64::Bcc) {
for (MachineInstr &MI : reverse(*LoopBB)) {
if (MI.modifiesRegister(AArch64::NZCV, &TRI)) {
PredBranch = &MI;
break;
}
}
if (!PredBranch)
return nullptr;
} else if (isCompareAndBranch(CondBranch->getOpcode())) {
const MachineRegisterInfo &MRI = LoopBB->getParent()->getRegInfo();
Register Reg = CondBranch->getOperand(0).getReg();
if (!Reg.isVirtual())
return nullptr;
PredBranch = MRI.getVRegDef(Reg);
// MachinePipeliner does not expect that the immediate predecessor is a Phi
if (PredBranch->isPHI())
return nullptr;
if (PredBranch->getParent() != LoopBB)
return nullptr;
} else {
return nullptr;
}
return std::make_unique<AArch64PipelinerLoopInfo>(PredBranch, Cond);
}
#define GET_INSTRINFO_HELPERS
#define GET_INSTRMAP_INFO
#include "AArch64GenInstrInfo.inc"