| //===- MipsInstrInfo.cpp - Mips 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 Mips implementation of the TargetInstrInfo class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "MipsInstrInfo.h" |
| #include "MCTargetDesc/MipsBaseInfo.h" |
| #include "MCTargetDesc/MipsMCTargetDesc.h" |
| #include "MipsSubtarget.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/CodeGen/MachineBasicBlock.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/MachineInstr.h" |
| #include "llvm/CodeGen/MachineInstrBuilder.h" |
| #include "llvm/CodeGen/MachineOperand.h" |
| #include "llvm/CodeGen/TargetOpcodes.h" |
| #include "llvm/CodeGen/TargetSubtargetInfo.h" |
| #include "llvm/IR/DebugInfoMetadata.h" |
| #include "llvm/IR/DebugLoc.h" |
| #include "llvm/MC/MCInstrDesc.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include <cassert> |
| |
| using namespace llvm; |
| |
| #define GET_INSTRINFO_CTOR_DTOR |
| #include "MipsGenInstrInfo.inc" |
| |
| // Pin the vtable to this file. |
| void MipsInstrInfo::anchor() {} |
| |
| MipsInstrInfo::MipsInstrInfo(const MipsSubtarget &STI, unsigned UncondBr) |
| : MipsGenInstrInfo(Mips::ADJCALLSTACKDOWN, Mips::ADJCALLSTACKUP), |
| Subtarget(STI), UncondBrOpc(UncondBr) {} |
| |
| const MipsInstrInfo *MipsInstrInfo::create(MipsSubtarget &STI) { |
| if (STI.inMips16Mode()) |
| return createMips16InstrInfo(STI); |
| |
| return createMipsSEInstrInfo(STI); |
| } |
| |
| bool MipsInstrInfo::isZeroImm(const MachineOperand &op) const { |
| return op.isImm() && op.getImm() == 0; |
| } |
| |
| /// insertNoop - If data hazard condition is found insert the target nop |
| /// instruction. |
| // FIXME: This appears to be dead code. |
| void MipsInstrInfo:: |
| insertNoop(MachineBasicBlock &MBB, MachineBasicBlock::iterator MI) const |
| { |
| DebugLoc DL; |
| BuildMI(MBB, MI, DL, get(Mips::NOP)); |
| } |
| |
| MachineMemOperand * |
| MipsInstrInfo::GetMemOperand(MachineBasicBlock &MBB, int FI, |
| MachineMemOperand::Flags Flags) const { |
| MachineFunction &MF = *MBB.getParent(); |
| MachineFrameInfo &MFI = MF.getFrameInfo(); |
| |
| return MF.getMachineMemOperand(MachinePointerInfo::getFixedStack(MF, FI), |
| Flags, MFI.getObjectSize(FI), |
| MFI.getObjectAlign(FI)); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Branch Analysis |
| //===----------------------------------------------------------------------===// |
| |
| void MipsInstrInfo::AnalyzeCondBr(const MachineInstr *Inst, unsigned Opc, |
| MachineBasicBlock *&BB, |
| SmallVectorImpl<MachineOperand> &Cond) const { |
| assert(getAnalyzableBrOpc(Opc) && "Not an analyzable branch"); |
| int NumOp = Inst->getNumExplicitOperands(); |
| |
| // for both int and fp branches, the last explicit operand is the |
| // MBB. |
| BB = Inst->getOperand(NumOp-1).getMBB(); |
| Cond.push_back(MachineOperand::CreateImm(Opc)); |
| |
| for (int i = 0; i < NumOp-1; i++) |
| Cond.push_back(Inst->getOperand(i)); |
| } |
| |
| bool MipsInstrInfo::analyzeBranch(MachineBasicBlock &MBB, |
| MachineBasicBlock *&TBB, |
| MachineBasicBlock *&FBB, |
| SmallVectorImpl<MachineOperand> &Cond, |
| bool AllowModify) const { |
| SmallVector<MachineInstr*, 2> BranchInstrs; |
| BranchType BT = analyzeBranch(MBB, TBB, FBB, Cond, AllowModify, BranchInstrs); |
| |
| return (BT == BT_None) || (BT == BT_Indirect); |
| } |
| |
| void MipsInstrInfo::BuildCondBr(MachineBasicBlock &MBB, MachineBasicBlock *TBB, |
| const DebugLoc &DL, |
| ArrayRef<MachineOperand> Cond) const { |
| unsigned Opc = Cond[0].getImm(); |
| const MCInstrDesc &MCID = get(Opc); |
| MachineInstrBuilder MIB = BuildMI(&MBB, DL, MCID); |
| |
| for (unsigned i = 1; i < Cond.size(); ++i) { |
| assert((Cond[i].isImm() || Cond[i].isReg()) && |
| "Cannot copy operand for conditional branch!"); |
| MIB.add(Cond[i]); |
| } |
| MIB.addMBB(TBB); |
| } |
| |
| unsigned MipsInstrInfo::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"); |
| assert(!BytesAdded && "code size not handled"); |
| |
| // # of condition operands: |
| // Unconditional branches: 0 |
| // Floating point branches: 1 (opc) |
| // Int BranchZero: 2 (opc, reg) |
| // Int Branch: 3 (opc, reg0, reg1) |
| assert((Cond.size() <= 3) && |
| "# of Mips branch conditions must be <= 3!"); |
| |
| // Two-way Conditional branch. |
| if (FBB) { |
| BuildCondBr(MBB, TBB, DL, Cond); |
| BuildMI(&MBB, DL, get(UncondBrOpc)).addMBB(FBB); |
| return 2; |
| } |
| |
| // One way branch. |
| // Unconditional branch. |
| if (Cond.empty()) |
| BuildMI(&MBB, DL, get(UncondBrOpc)).addMBB(TBB); |
| else // Conditional branch. |
| BuildCondBr(MBB, TBB, DL, Cond); |
| return 1; |
| } |
| |
| unsigned MipsInstrInfo::removeBranch(MachineBasicBlock &MBB, |
| int *BytesRemoved) const { |
| assert(!BytesRemoved && "code size not handled"); |
| |
| MachineBasicBlock::reverse_iterator I = MBB.rbegin(), REnd = MBB.rend(); |
| unsigned removed = 0; |
| |
| // Up to 2 branches are removed. |
| // Note that indirect branches are not removed. |
| while (I != REnd && removed < 2) { |
| // Skip past debug instructions. |
| if (I->isDebugInstr()) { |
| ++I; |
| continue; |
| } |
| if (!getAnalyzableBrOpc(I->getOpcode())) |
| break; |
| // Remove the branch. |
| I->eraseFromParent(); |
| I = MBB.rbegin(); |
| ++removed; |
| } |
| |
| return removed; |
| } |
| |
| /// reverseBranchCondition - Return the inverse opcode of the |
| /// specified Branch instruction. |
| bool MipsInstrInfo::reverseBranchCondition( |
| SmallVectorImpl<MachineOperand> &Cond) const { |
| assert( (Cond.size() && Cond.size() <= 3) && |
| "Invalid Mips branch condition!"); |
| Cond[0].setImm(getOppositeBranchOpc(Cond[0].getImm())); |
| return false; |
| } |
| |
| MipsInstrInfo::BranchType MipsInstrInfo::analyzeBranch( |
| MachineBasicBlock &MBB, MachineBasicBlock *&TBB, MachineBasicBlock *&FBB, |
| SmallVectorImpl<MachineOperand> &Cond, bool AllowModify, |
| SmallVectorImpl<MachineInstr *> &BranchInstrs) const { |
| MachineBasicBlock::reverse_iterator I = MBB.rbegin(), REnd = MBB.rend(); |
| |
| // Skip all the debug instructions. |
| while (I != REnd && I->isDebugInstr()) |
| ++I; |
| |
| if (I == REnd || !isUnpredicatedTerminator(*I)) { |
| // This block ends with no branches (it just falls through to its succ). |
| // Leave TBB/FBB null. |
| TBB = FBB = nullptr; |
| return BT_NoBranch; |
| } |
| |
| MachineInstr *LastInst = &*I; |
| unsigned LastOpc = LastInst->getOpcode(); |
| BranchInstrs.push_back(LastInst); |
| |
| // Not an analyzable branch (e.g., indirect jump). |
| if (!getAnalyzableBrOpc(LastOpc)) |
| return LastInst->isIndirectBranch() ? BT_Indirect : BT_None; |
| |
| // Get the second to last instruction in the block. |
| unsigned SecondLastOpc = 0; |
| MachineInstr *SecondLastInst = nullptr; |
| |
| // Skip past any debug instruction to see if the second last actual |
| // is a branch. |
| ++I; |
| while (I != REnd && I->isDebugInstr()) |
| ++I; |
| |
| if (I != REnd) { |
| SecondLastInst = &*I; |
| SecondLastOpc = getAnalyzableBrOpc(SecondLastInst->getOpcode()); |
| |
| // Not an analyzable branch (must be an indirect jump). |
| if (isUnpredicatedTerminator(*SecondLastInst) && !SecondLastOpc) |
| return BT_None; |
| } |
| |
| // If there is only one terminator instruction, process it. |
| if (!SecondLastOpc) { |
| // Unconditional branch. |
| if (LastInst->isUnconditionalBranch()) { |
| TBB = LastInst->getOperand(0).getMBB(); |
| return BT_Uncond; |
| } |
| |
| // Conditional branch |
| AnalyzeCondBr(LastInst, LastOpc, TBB, Cond); |
| return BT_Cond; |
| } |
| |
| // If we reached here, there are two branches. |
| // If there are three terminators, we don't know what sort of block this is. |
| if (++I != REnd && isUnpredicatedTerminator(*I)) |
| return BT_None; |
| |
| BranchInstrs.insert(BranchInstrs.begin(), SecondLastInst); |
| |
| // If second to last instruction is an unconditional branch, |
| // analyze it and remove the last instruction. |
| if (SecondLastInst->isUnconditionalBranch()) { |
| // Return if the last instruction cannot be removed. |
| if (!AllowModify) |
| return BT_None; |
| |
| TBB = SecondLastInst->getOperand(0).getMBB(); |
| LastInst->eraseFromParent(); |
| BranchInstrs.pop_back(); |
| return BT_Uncond; |
| } |
| |
| // Conditional branch followed by an unconditional branch. |
| // The last one must be unconditional. |
| if (!LastInst->isUnconditionalBranch()) |
| return BT_None; |
| |
| AnalyzeCondBr(SecondLastInst, SecondLastOpc, TBB, Cond); |
| FBB = LastInst->getOperand(0).getMBB(); |
| |
| return BT_CondUncond; |
| } |
| |
| bool MipsInstrInfo::isBranchOffsetInRange(unsigned BranchOpc, |
| int64_t BrOffset) const { |
| switch (BranchOpc) { |
| case Mips::B: |
| case Mips::BAL: |
| case Mips::BAL_BR: |
| case Mips::BAL_BR_MM: |
| case Mips::BC1F: |
| case Mips::BC1FL: |
| case Mips::BC1T: |
| case Mips::BC1TL: |
| case Mips::BEQ: case Mips::BEQ64: |
| case Mips::BEQL: |
| case Mips::BGEZ: case Mips::BGEZ64: |
| case Mips::BGEZL: |
| case Mips::BGEZAL: |
| case Mips::BGEZALL: |
| case Mips::BGTZ: case Mips::BGTZ64: |
| case Mips::BGTZL: |
| case Mips::BLEZ: case Mips::BLEZ64: |
| case Mips::BLEZL: |
| case Mips::BLTZ: case Mips::BLTZ64: |
| case Mips::BLTZL: |
| case Mips::BLTZAL: |
| case Mips::BLTZALL: |
| case Mips::BNE: case Mips::BNE64: |
| case Mips::BNEL: |
| return isInt<18>(BrOffset); |
| |
| // microMIPSr3 branches |
| case Mips::B_MM: |
| case Mips::BC1F_MM: |
| case Mips::BC1T_MM: |
| case Mips::BEQ_MM: |
| case Mips::BGEZ_MM: |
| case Mips::BGEZAL_MM: |
| case Mips::BGTZ_MM: |
| case Mips::BLEZ_MM: |
| case Mips::BLTZ_MM: |
| case Mips::BLTZAL_MM: |
| case Mips::BNE_MM: |
| case Mips::BEQZC_MM: |
| case Mips::BNEZC_MM: |
| return isInt<17>(BrOffset); |
| |
| // microMIPSR3 short branches. |
| case Mips::B16_MM: |
| return isInt<11>(BrOffset); |
| |
| case Mips::BEQZ16_MM: |
| case Mips::BNEZ16_MM: |
| return isInt<8>(BrOffset); |
| |
| // MIPSR6 branches. |
| case Mips::BALC: |
| case Mips::BC: |
| return isInt<28>(BrOffset); |
| |
| case Mips::BC1EQZ: |
| case Mips::BC1NEZ: |
| case Mips::BC2EQZ: |
| case Mips::BC2NEZ: |
| case Mips::BEQC: case Mips::BEQC64: |
| case Mips::BNEC: case Mips::BNEC64: |
| case Mips::BGEC: case Mips::BGEC64: |
| case Mips::BGEUC: case Mips::BGEUC64: |
| case Mips::BGEZC: case Mips::BGEZC64: |
| case Mips::BGTZC: case Mips::BGTZC64: |
| case Mips::BLEZC: case Mips::BLEZC64: |
| case Mips::BLTC: case Mips::BLTC64: |
| case Mips::BLTUC: case Mips::BLTUC64: |
| case Mips::BLTZC: case Mips::BLTZC64: |
| case Mips::BNVC: |
| case Mips::BOVC: |
| case Mips::BGEZALC: |
| case Mips::BEQZALC: |
| case Mips::BGTZALC: |
| case Mips::BLEZALC: |
| case Mips::BLTZALC: |
| case Mips::BNEZALC: |
| return isInt<18>(BrOffset); |
| |
| case Mips::BEQZC: case Mips::BEQZC64: |
| case Mips::BNEZC: case Mips::BNEZC64: |
| return isInt<23>(BrOffset); |
| |
| // microMIPSR6 branches |
| case Mips::BC16_MMR6: |
| return isInt<11>(BrOffset); |
| |
| case Mips::BEQZC16_MMR6: |
| case Mips::BNEZC16_MMR6: |
| return isInt<8>(BrOffset); |
| |
| case Mips::BALC_MMR6: |
| case Mips::BC_MMR6: |
| return isInt<27>(BrOffset); |
| |
| case Mips::BC1EQZC_MMR6: |
| case Mips::BC1NEZC_MMR6: |
| case Mips::BC2EQZC_MMR6: |
| case Mips::BC2NEZC_MMR6: |
| case Mips::BGEZALC_MMR6: |
| case Mips::BEQZALC_MMR6: |
| case Mips::BGTZALC_MMR6: |
| case Mips::BLEZALC_MMR6: |
| case Mips::BLTZALC_MMR6: |
| case Mips::BNEZALC_MMR6: |
| case Mips::BNVC_MMR6: |
| case Mips::BOVC_MMR6: |
| return isInt<17>(BrOffset); |
| |
| case Mips::BEQC_MMR6: |
| case Mips::BNEC_MMR6: |
| case Mips::BGEC_MMR6: |
| case Mips::BGEUC_MMR6: |
| case Mips::BGEZC_MMR6: |
| case Mips::BGTZC_MMR6: |
| case Mips::BLEZC_MMR6: |
| case Mips::BLTC_MMR6: |
| case Mips::BLTUC_MMR6: |
| case Mips::BLTZC_MMR6: |
| return isInt<18>(BrOffset); |
| |
| case Mips::BEQZC_MMR6: |
| case Mips::BNEZC_MMR6: |
| return isInt<23>(BrOffset); |
| |
| // DSP branches. |
| case Mips::BPOSGE32: |
| return isInt<18>(BrOffset); |
| case Mips::BPOSGE32_MM: |
| case Mips::BPOSGE32C_MMR3: |
| return isInt<17>(BrOffset); |
| |
| // cnMIPS branches. |
| case Mips::BBIT0: |
| case Mips::BBIT032: |
| case Mips::BBIT1: |
| case Mips::BBIT132: |
| return isInt<18>(BrOffset); |
| |
| // MSA branches. |
| case Mips::BZ_B: |
| case Mips::BZ_H: |
| case Mips::BZ_W: |
| case Mips::BZ_D: |
| case Mips::BZ_V: |
| case Mips::BNZ_B: |
| case Mips::BNZ_H: |
| case Mips::BNZ_W: |
| case Mips::BNZ_D: |
| case Mips::BNZ_V: |
| return isInt<18>(BrOffset); |
| } |
| |
| llvm_unreachable("Unknown branch instruction!"); |
| } |
| |
| /// Return the corresponding compact (no delay slot) form of a branch. |
| unsigned MipsInstrInfo::getEquivalentCompactForm( |
| const MachineBasicBlock::iterator I) const { |
| unsigned Opcode = I->getOpcode(); |
| bool canUseShortMicroMipsCTI = false; |
| |
| if (Subtarget.inMicroMipsMode()) { |
| switch (Opcode) { |
| case Mips::BNE: |
| case Mips::BNE_MM: |
| case Mips::BEQ: |
| case Mips::BEQ_MM: |
| // microMIPS has NE,EQ branches that do not have delay slots provided one |
| // of the operands is zero. |
| if (I->getOperand(1).getReg() == Subtarget.getABI().GetZeroReg()) |
| canUseShortMicroMipsCTI = true; |
| break; |
| // For microMIPS the PseudoReturn and PseudoIndirectBranch are always |
| // expanded to JR_MM, so they can be replaced with JRC16_MM. |
| case Mips::JR: |
| case Mips::PseudoReturn: |
| case Mips::PseudoIndirectBranch: |
| canUseShortMicroMipsCTI = true; |
| break; |
| } |
| } |
| |
| // MIPSR6 forbids both operands being the zero register. |
| if (Subtarget.hasMips32r6() && (I->getNumOperands() > 1) && |
| (I->getOperand(0).isReg() && |
| (I->getOperand(0).getReg() == Mips::ZERO || |
| I->getOperand(0).getReg() == Mips::ZERO_64)) && |
| (I->getOperand(1).isReg() && |
| (I->getOperand(1).getReg() == Mips::ZERO || |
| I->getOperand(1).getReg() == Mips::ZERO_64))) |
| return 0; |
| |
| if (Subtarget.hasMips32r6() || canUseShortMicroMipsCTI) { |
| switch (Opcode) { |
| case Mips::B: |
| return Mips::BC; |
| case Mips::BAL: |
| return Mips::BALC; |
| case Mips::BEQ: |
| case Mips::BEQ_MM: |
| if (canUseShortMicroMipsCTI) |
| return Mips::BEQZC_MM; |
| else if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BEQC; |
| case Mips::BNE: |
| case Mips::BNE_MM: |
| if (canUseShortMicroMipsCTI) |
| return Mips::BNEZC_MM; |
| else if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BNEC; |
| case Mips::BGE: |
| if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BGEC; |
| case Mips::BGEU: |
| if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BGEUC; |
| case Mips::BGEZ: |
| return Mips::BGEZC; |
| case Mips::BGTZ: |
| return Mips::BGTZC; |
| case Mips::BLEZ: |
| return Mips::BLEZC; |
| case Mips::BLT: |
| if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BLTC; |
| case Mips::BLTU: |
| if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BLTUC; |
| case Mips::BLTZ: |
| return Mips::BLTZC; |
| case Mips::BEQ64: |
| if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BEQC64; |
| case Mips::BNE64: |
| if (I->getOperand(0).getReg() == I->getOperand(1).getReg()) |
| return 0; |
| return Mips::BNEC64; |
| case Mips::BGTZ64: |
| return Mips::BGTZC64; |
| case Mips::BGEZ64: |
| return Mips::BGEZC64; |
| case Mips::BLTZ64: |
| return Mips::BLTZC64; |
| case Mips::BLEZ64: |
| return Mips::BLEZC64; |
| // For MIPSR6, the instruction 'jic' can be used for these cases. Some |
| // tools will accept 'jrc reg' as an alias for 'jic 0, $reg'. |
| case Mips::JR: |
| case Mips::PseudoIndirectBranchR6: |
| case Mips::PseudoReturn: |
| case Mips::TAILCALLR6REG: |
| if (canUseShortMicroMipsCTI) |
| return Mips::JRC16_MM; |
| return Mips::JIC; |
| case Mips::JALRPseudo: |
| return Mips::JIALC; |
| case Mips::JR64: |
| case Mips::PseudoIndirectBranch64R6: |
| case Mips::PseudoReturn64: |
| case Mips::TAILCALL64R6REG: |
| return Mips::JIC64; |
| case Mips::JALR64Pseudo: |
| return Mips::JIALC64; |
| default: |
| return 0; |
| } |
| } |
| |
| return 0; |
| } |
| |
| /// Predicate for distingushing between control transfer instructions and all |
| /// other instructions for handling forbidden slots. Consider inline assembly |
| /// as unsafe as well. |
| bool MipsInstrInfo::SafeInForbiddenSlot(const MachineInstr &MI) const { |
| if (MI.isInlineAsm()) |
| return false; |
| |
| return (MI.getDesc().TSFlags & MipsII::IsCTI) == 0; |
| } |
| |
| /// Predicate for distingushing instructions that have forbidden slots. |
| bool MipsInstrInfo::HasForbiddenSlot(const MachineInstr &MI) const { |
| return (MI.getDesc().TSFlags & MipsII::HasForbiddenSlot) != 0; |
| } |
| |
| /// Return the number of bytes of code the specified instruction may be. |
| unsigned MipsInstrInfo::getInstSizeInBytes(const MachineInstr &MI) const { |
| switch (MI.getOpcode()) { |
| default: |
| return MI.getDesc().getSize(); |
| case TargetOpcode::INLINEASM: |
| case TargetOpcode::INLINEASM_BR: { // Inline Asm: Variable size. |
| const MachineFunction *MF = MI.getParent()->getParent(); |
| const char *AsmStr = MI.getOperand(0).getSymbolName(); |
| return getInlineAsmLength(AsmStr, *MF->getTarget().getMCAsmInfo()); |
| } |
| case Mips::CONSTPOOL_ENTRY: |
| // If this machine instr is a constant pool entry, its size is recorded as |
| // operand #2. |
| return MI.getOperand(2).getImm(); |
| } |
| } |
| |
| MachineInstrBuilder |
| MipsInstrInfo::genInstrWithNewOpc(unsigned NewOpc, |
| MachineBasicBlock::iterator I) const { |
| MachineInstrBuilder MIB; |
| |
| // Certain branches have two forms: e.g beq $1, $zero, dest vs beqz $1, dest |
| // Pick the zero form of the branch for readable assembly and for greater |
| // branch distance in non-microMIPS mode. |
| // Additional MIPSR6 does not permit the use of register $zero for compact |
| // branches. |
| // FIXME: Certain atomic sequences on mips64 generate 32bit references to |
| // Mips::ZERO, which is incorrect. This test should be updated to use |
| // Subtarget.getABI().GetZeroReg() when those atomic sequences and others |
| // are fixed. |
| int ZeroOperandPosition = -1; |
| bool BranchWithZeroOperand = false; |
| if (I->isBranch() && !I->isPseudo()) { |
| auto TRI = I->getParent()->getParent()->getSubtarget().getRegisterInfo(); |
| ZeroOperandPosition = I->findRegisterUseOperandIdx(Mips::ZERO, false, TRI); |
| BranchWithZeroOperand = ZeroOperandPosition != -1; |
| } |
| |
| if (BranchWithZeroOperand) { |
| switch (NewOpc) { |
| case Mips::BEQC: |
| NewOpc = Mips::BEQZC; |
| break; |
| case Mips::BNEC: |
| NewOpc = Mips::BNEZC; |
| break; |
| case Mips::BGEC: |
| NewOpc = Mips::BGEZC; |
| break; |
| case Mips::BLTC: |
| NewOpc = Mips::BLTZC; |
| break; |
| case Mips::BEQC64: |
| NewOpc = Mips::BEQZC64; |
| break; |
| case Mips::BNEC64: |
| NewOpc = Mips::BNEZC64; |
| break; |
| } |
| } |
| |
| MIB = BuildMI(*I->getParent(), I, I->getDebugLoc(), get(NewOpc)); |
| |
| // For MIPSR6 JI*C requires an immediate 0 as an operand, JIALC(64) an |
| // immediate 0 as an operand and requires the removal of it's implicit-def %ra |
| // implicit operand as copying the implicit operations of the instructio we're |
| // looking at will give us the correct flags. |
| if (NewOpc == Mips::JIC || NewOpc == Mips::JIALC || NewOpc == Mips::JIC64 || |
| NewOpc == Mips::JIALC64) { |
| |
| if (NewOpc == Mips::JIALC || NewOpc == Mips::JIALC64) |
| MIB->RemoveOperand(0); |
| |
| for (unsigned J = 0, E = I->getDesc().getNumOperands(); J < E; ++J) { |
| MIB.add(I->getOperand(J)); |
| } |
| |
| MIB.addImm(0); |
| |
| // If I has an MCSymbol operand (used by asm printer, to emit R_MIPS_JALR), |
| // add it to the new instruction. |
| for (unsigned J = I->getDesc().getNumOperands(), E = I->getNumOperands(); |
| J < E; ++J) { |
| const MachineOperand &MO = I->getOperand(J); |
| if (MO.isMCSymbol() && (MO.getTargetFlags() & MipsII::MO_JALR)) |
| MIB.addSym(MO.getMCSymbol(), MipsII::MO_JALR); |
| } |
| |
| |
| } else { |
| for (unsigned J = 0, E = I->getDesc().getNumOperands(); J < E; ++J) { |
| if (BranchWithZeroOperand && (unsigned)ZeroOperandPosition == J) |
| continue; |
| |
| MIB.add(I->getOperand(J)); |
| } |
| } |
| |
| MIB.copyImplicitOps(*I); |
| MIB.cloneMemRefs(*I); |
| return MIB; |
| } |
| |
| bool MipsInstrInfo::findCommutedOpIndices(const MachineInstr &MI, |
| unsigned &SrcOpIdx1, |
| unsigned &SrcOpIdx2) const { |
| assert(!MI.isBundle() && |
| "TargetInstrInfo::findCommutedOpIndices() can't handle bundles"); |
| |
| const MCInstrDesc &MCID = MI.getDesc(); |
| if (!MCID.isCommutable()) |
| return false; |
| |
| switch (MI.getOpcode()) { |
| case Mips::DPADD_U_H: |
| case Mips::DPADD_U_W: |
| case Mips::DPADD_U_D: |
| case Mips::DPADD_S_H: |
| case Mips::DPADD_S_W: |
| case Mips::DPADD_S_D: |
| // The first operand is both input and output, so it should not commute |
| if (!fixCommutedOpIndices(SrcOpIdx1, SrcOpIdx2, 2, 3)) |
| return false; |
| |
| if (!MI.getOperand(SrcOpIdx1).isReg() || !MI.getOperand(SrcOpIdx2).isReg()) |
| return false; |
| return true; |
| } |
| return TargetInstrInfo::findCommutedOpIndices(MI, SrcOpIdx1, SrcOpIdx2); |
| } |
| |
| // ins, ext, dext*, dins have the following constraints: |
| // X <= pos < Y |
| // X < size <= Y |
| // X < pos+size <= Y |
| // |
| // dinsm and dinsu have the following constraints: |
| // X <= pos < Y |
| // X <= size <= Y |
| // X < pos+size <= Y |
| // |
| // The callee of verifyInsExtInstruction however gives the bounds of |
| // dins[um] like the other (d)ins (d)ext(um) instructions, so that this |
| // function doesn't have to vary it's behaviour based on the instruction |
| // being checked. |
| static bool verifyInsExtInstruction(const MachineInstr &MI, StringRef &ErrInfo, |
| const int64_t PosLow, const int64_t PosHigh, |
| const int64_t SizeLow, |
| const int64_t SizeHigh, |
| const int64_t BothLow, |
| const int64_t BothHigh) { |
| MachineOperand MOPos = MI.getOperand(2); |
| if (!MOPos.isImm()) { |
| ErrInfo = "Position is not an immediate!"; |
| return false; |
| } |
| int64_t Pos = MOPos.getImm(); |
| if (!((PosLow <= Pos) && (Pos < PosHigh))) { |
| ErrInfo = "Position operand is out of range!"; |
| return false; |
| } |
| |
| MachineOperand MOSize = MI.getOperand(3); |
| if (!MOSize.isImm()) { |
| ErrInfo = "Size operand is not an immediate!"; |
| return false; |
| } |
| int64_t Size = MOSize.getImm(); |
| if (!((SizeLow < Size) && (Size <= SizeHigh))) { |
| ErrInfo = "Size operand is out of range!"; |
| return false; |
| } |
| |
| if (!((BothLow < (Pos + Size)) && ((Pos + Size) <= BothHigh))) { |
| ErrInfo = "Position + Size is out of range!"; |
| return false; |
| } |
| |
| return true; |
| } |
| |
| // Perform target specific instruction verification. |
| bool MipsInstrInfo::verifyInstruction(const MachineInstr &MI, |
| StringRef &ErrInfo) const { |
| // Verify that ins and ext instructions are well formed. |
| switch (MI.getOpcode()) { |
| case Mips::EXT: |
| case Mips::EXT_MM: |
| case Mips::INS: |
| case Mips::INS_MM: |
| case Mips::DINS: |
| return verifyInsExtInstruction(MI, ErrInfo, 0, 32, 0, 32, 0, 32); |
| case Mips::DINSM: |
| // The ISA spec has a subtle difference between dinsm and dextm |
| // in that it says: |
| // 2 <= size <= 64 for 'dinsm' but 'dextm' has 32 < size <= 64. |
| // To make the bounds checks similar, the range 1 < size <= 64 is checked |
| // for 'dinsm'. |
| return verifyInsExtInstruction(MI, ErrInfo, 0, 32, 1, 64, 32, 64); |
| case Mips::DINSU: |
| // The ISA spec has a subtle difference between dinsu and dextu in that |
| // the size range of dinsu is specified as 1 <= size <= 32 whereas size |
| // for dextu is 0 < size <= 32. The range checked for dinsu here is |
| // 0 < size <= 32, which is equivalent and similar to dextu. |
| return verifyInsExtInstruction(MI, ErrInfo, 32, 64, 0, 32, 32, 64); |
| case Mips::DEXT: |
| return verifyInsExtInstruction(MI, ErrInfo, 0, 32, 0, 32, 0, 63); |
| case Mips::DEXTM: |
| return verifyInsExtInstruction(MI, ErrInfo, 0, 32, 32, 64, 32, 64); |
| case Mips::DEXTU: |
| return verifyInsExtInstruction(MI, ErrInfo, 32, 64, 0, 32, 32, 64); |
| case Mips::TAILCALLREG: |
| case Mips::PseudoIndirectBranch: |
| case Mips::JR: |
| case Mips::JR64: |
| case Mips::JALR: |
| case Mips::JALR64: |
| case Mips::JALRPseudo: |
| if (!Subtarget.useIndirectJumpsHazard()) |
| return true; |
| |
| ErrInfo = "invalid instruction when using jump guards!"; |
| return false; |
| default: |
| return true; |
| } |
| |
| return true; |
| } |
| |
| std::pair<unsigned, unsigned> |
| MipsInstrInfo::decomposeMachineOperandsTargetFlags(unsigned TF) const { |
| return std::make_pair(TF, 0u); |
| } |
| |
| ArrayRef<std::pair<unsigned, const char*>> |
| MipsInstrInfo::getSerializableDirectMachineOperandTargetFlags() const { |
| using namespace MipsII; |
| |
| static const std::pair<unsigned, const char*> Flags[] = { |
| {MO_GOT, "mips-got"}, |
| {MO_GOT_CALL, "mips-got-call"}, |
| {MO_GPREL, "mips-gprel"}, |
| {MO_ABS_HI, "mips-abs-hi"}, |
| {MO_ABS_LO, "mips-abs-lo"}, |
| {MO_TLSGD, "mips-tlsgd"}, |
| {MO_TLSLDM, "mips-tlsldm"}, |
| {MO_DTPREL_HI, "mips-dtprel-hi"}, |
| {MO_DTPREL_LO, "mips-dtprel-lo"}, |
| {MO_GOTTPREL, "mips-gottprel"}, |
| {MO_TPREL_HI, "mips-tprel-hi"}, |
| {MO_TPREL_LO, "mips-tprel-lo"}, |
| {MO_GPOFF_HI, "mips-gpoff-hi"}, |
| {MO_GPOFF_LO, "mips-gpoff-lo"}, |
| {MO_GOT_DISP, "mips-got-disp"}, |
| {MO_GOT_PAGE, "mips-got-page"}, |
| {MO_GOT_OFST, "mips-got-ofst"}, |
| {MO_HIGHER, "mips-higher"}, |
| {MO_HIGHEST, "mips-highest"}, |
| {MO_GOT_HI16, "mips-got-hi16"}, |
| {MO_GOT_LO16, "mips-got-lo16"}, |
| {MO_CALL_HI16, "mips-call-hi16"}, |
| {MO_CALL_LO16, "mips-call-lo16"}, |
| {MO_JALR, "mips-jalr"} |
| }; |
| return makeArrayRef(Flags); |
| } |
| |
| Optional<ParamLoadedValue> |
| MipsInstrInfo::describeLoadedValue(const MachineInstr &MI, Register Reg) const { |
| DIExpression *Expr = |
| DIExpression::get(MI.getMF()->getFunction().getContext(), {}); |
| |
| // TODO: Special MIPS instructions that need to be described separately. |
| if (auto RegImm = isAddImmediate(MI, Reg)) { |
| Register SrcReg = RegImm->Reg; |
| int64_t Offset = RegImm->Imm; |
| // When SrcReg is $zero, treat loaded value as immediate only. |
| // Ex. $a2 = ADDiu $zero, 10 |
| if (SrcReg == Mips::ZERO || SrcReg == Mips::ZERO_64) { |
| return ParamLoadedValue(MI.getOperand(2), Expr); |
| } |
| Expr = DIExpression::prepend(Expr, DIExpression::ApplyOffset, Offset); |
| return ParamLoadedValue(MachineOperand::CreateReg(SrcReg, false), Expr); |
| } else if (auto DestSrc = isCopyInstr(MI)) { |
| const MachineFunction *MF = MI.getMF(); |
| const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo(); |
| Register DestReg = DestSrc->Destination->getReg(); |
| // TODO: Handle cases where the Reg is sub- or super-register of the |
| // DestReg. |
| if (TRI->isSuperRegister(Reg, DestReg) || TRI->isSubRegister(Reg, DestReg)) |
| return None; |
| } |
| |
| return TargetInstrInfo::describeLoadedValue(MI, Reg); |
| } |
| |
| Optional<RegImmPair> MipsInstrInfo::isAddImmediate(const MachineInstr &MI, |
| Register Reg) const { |
| // 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 None; |
| |
| switch (MI.getOpcode()) { |
| case Mips::ADDiu: |
| case Mips::DADDiu: { |
| const MachineOperand &Dop = MI.getOperand(0); |
| const MachineOperand &Sop1 = MI.getOperand(1); |
| const MachineOperand &Sop2 = MI.getOperand(2); |
| // Value is sum of register and immediate. Immediate value could be |
| // global string address which is not supported. |
| if (Dop.isReg() && Sop1.isReg() && Sop2.isImm()) |
| return RegImmPair{Sop1.getReg(), Sop2.getImm()}; |
| // TODO: Handle case where Sop1 is a frame-index. |
| } |
| } |
| return None; |
| } |
