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llvm / llvm-project / 27f06dd6a7a978e9a88cecfba926e50f16a1c7c3 / . / llvm / lib / CodeGen / ExpandFp.cpp
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//===--- ExpandFp.cpp - Expand fp instructions ----------------------------===//
//
// 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 pass expands certain floating point instructions at the IR level.
//
// It expands ‘fptoui .. to’, ‘fptosi .. to’, ‘uitofp .. to’, ‘sitofp
// .. to’ instructions with a bitwidth above a threshold. This is
// useful for targets like x86_64 that cannot lower fp convertions
// with more than 128 bits.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/ExpandFp.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Analysis/GlobalsModRef.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/CodeGen/TargetLowering.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/InstIterator.h"
#include "llvm/IR/PassManager.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Target/TargetMachine.h"
using namespace llvm;
static cl::opt<unsigned>
ExpandFpConvertBits("expand-fp-convert-bits", cl::Hidden,
cl::init(llvm::IntegerType::MAX_INT_BITS),
cl::desc("fp convert instructions on integers with "
"more than <N> bits are expanded."));
// clang-format off: preserve formatting of the following example
/// Generate code to convert a fp number to integer, replacing FPToS(U)I with
/// the generated code. This currently generates code similarly to compiler-rt's
/// implementations.
///
/// An example IR generated from compiler-rt/fixsfdi.c looks like below:
/// define dso_local i64 @foo(float noundef %a) local_unnamed_addr #0 {
/// entry:
/// %0 = bitcast float %a to i32
/// %conv.i = zext i32 %0 to i64
/// %tobool.not = icmp sgt i32 %0, -1
/// %conv = select i1 %tobool.not, i64 1, i64 -1
/// %and = lshr i64 %conv.i, 23
/// %shr = and i64 %and, 255
/// %and2 = and i64 %conv.i, 8388607
/// %or = or i64 %and2, 8388608
/// %cmp = icmp ult i64 %shr, 127
/// br i1 %cmp, label %cleanup, label %if.end
///
/// if.end: ; preds = %entry
/// %sub = add nuw nsw i64 %shr, 4294967169
/// %conv5 = and i64 %sub, 4294967232
/// %cmp6.not = icmp eq i64 %conv5, 0
/// br i1 %cmp6.not, label %if.end12, label %if.then8
///
/// if.then8: ; preds = %if.end
/// %cond11 = select i1 %tobool.not, i64 9223372036854775807, i64 -9223372036854775808
/// br label %cleanup
///
/// if.end12: ; preds = %if.end
/// %cmp13 = icmp ult i64 %shr, 150
/// br i1 %cmp13, label %if.then15, label %if.else
///
/// if.then15: ; preds = %if.end12
/// %sub16 = sub nuw nsw i64 150, %shr
/// %shr17 = lshr i64 %or, %sub16
/// %mul = mul nsw i64 %shr17, %conv
/// br label %cleanup
///
/// if.else: ; preds = %if.end12
/// %sub18 = add nsw i64 %shr, -150
/// %shl = shl i64 %or, %sub18
/// %mul19 = mul nsw i64 %shl, %conv
/// br label %cleanup
///
/// cleanup: ; preds = %entry, %if.else, %if.then15, %if.then8
/// %retval.0 = phi i64 [ %cond11, %if.then8 ], [ %mul, %if.then15 ], [ %mul19, %if.else ], [ 0, %entry ]
/// ret i64 %retval.0
/// }
///
/// Replace fp to integer with generated code.
static void expandFPToI(Instruction *FPToI) {
// clang-format on
IRBuilder<> Builder(FPToI);
auto *FloatVal = FPToI->getOperand(0);
IntegerType *IntTy = cast<IntegerType>(FPToI->getType());
unsigned BitWidth = FPToI->getType()->getIntegerBitWidth();
unsigned FPMantissaWidth = FloatVal->getType()->getFPMantissaWidth() - 1;
// FIXME: fp16's range is covered by i32. So `fptoi half` can convert
// to i32 first following a sext/zext to target integer type.
Value *A1 = nullptr;
if (FloatVal->getType()->isHalfTy()) {
if (FPToI->getOpcode() == Instruction::FPToUI) {
Value *A0 = Builder.CreateFPToUI(FloatVal, Builder.getInt32Ty());
A1 = Builder.CreateZExt(A0, IntTy);
} else { // FPToSI
Value *A0 = Builder.CreateFPToSI(FloatVal, Builder.getInt32Ty());
A1 = Builder.CreateSExt(A0, IntTy);
}
FPToI->replaceAllUsesWith(A1);
FPToI->dropAllReferences();
FPToI->eraseFromParent();
return;
}
// fp80 conversion is implemented by fpext to fp128 first then do the
// conversion.
FPMantissaWidth = FPMantissaWidth == 63 ? 112 : FPMantissaWidth;
unsigned FloatWidth =
PowerOf2Ceil(FloatVal->getType()->getScalarSizeInBits());
unsigned ExponentWidth = FloatWidth - FPMantissaWidth - 1;
unsigned ExponentBias = (1 << (ExponentWidth - 1)) - 1;
Value *ImplicitBit = Builder.CreateShl(
Builder.getIntN(BitWidth, 1), Builder.getIntN(BitWidth, FPMantissaWidth));
Value *SignificandMask =
Builder.CreateSub(ImplicitBit, Builder.getIntN(BitWidth, 1));
Value *NegOne = Builder.CreateSExt(
ConstantInt::getSigned(Builder.getInt32Ty(), -1), IntTy);
Value *NegInf =
Builder.CreateShl(ConstantInt::getSigned(IntTy, 1),
ConstantInt::getSigned(IntTy, BitWidth - 1));
BasicBlock *Entry = Builder.GetInsertBlock();
Function *F = Entry->getParent();
Entry->setName(Twine(Entry->getName(), "fp-to-i-entry"));
BasicBlock *End =
Entry->splitBasicBlock(Builder.GetInsertPoint(), "fp-to-i-cleanup");
BasicBlock *IfEnd =
BasicBlock::Create(Builder.getContext(), "fp-to-i-if-end", F, End);
BasicBlock *IfThen5 =
BasicBlock::Create(Builder.getContext(), "fp-to-i-if-then5", F, End);
BasicBlock *IfEnd9 =
BasicBlock::Create(Builder.getContext(), "fp-to-i-if-end9", F, End);
BasicBlock *IfThen12 =
BasicBlock::Create(Builder.getContext(), "fp-to-i-if-then12", F, End);
BasicBlock *IfElse =
BasicBlock::Create(Builder.getContext(), "fp-to-i-if-else", F, End);
Entry->getTerminator()->eraseFromParent();
// entry:
Builder.SetInsertPoint(Entry);
Value *FloatVal0 = FloatVal;
// fp80 conversion is implemented by fpext to fp128 first then do the
// conversion.
if (FloatVal->getType()->isX86_FP80Ty())
FloatVal0 =
Builder.CreateFPExt(FloatVal, Type::getFP128Ty(Builder.getContext()));
Value *ARep0 =
Builder.CreateBitCast(FloatVal0, Builder.getIntNTy(FloatWidth));
Value *ARep = Builder.CreateZExt(ARep0, FPToI->getType());
Value *PosOrNeg = Builder.CreateICmpSGT(
ARep0, ConstantInt::getSigned(Builder.getIntNTy(FloatWidth), -1));
Value *Sign = Builder.CreateSelect(PosOrNeg, ConstantInt::getSigned(IntTy, 1),
ConstantInt::getSigned(IntTy, -1));
Value *And =
Builder.CreateLShr(ARep, Builder.getIntN(BitWidth, FPMantissaWidth));
Value *And2 = Builder.CreateAnd(
And, Builder.getIntN(BitWidth, (1 << ExponentWidth) - 1));
Value *Abs = Builder.CreateAnd(ARep, SignificandMask);
Value *Or = Builder.CreateOr(Abs, ImplicitBit);
Value *Cmp =
Builder.CreateICmpULT(And2, Builder.getIntN(BitWidth, ExponentBias));
Builder.CreateCondBr(Cmp, End, IfEnd);
// if.end:
Builder.SetInsertPoint(IfEnd);
Value *Add1 = Builder.CreateAdd(
And2, ConstantInt::getSigned(
IntTy, -static_cast<int64_t>(ExponentBias + BitWidth)));
Value *Cmp3 = Builder.CreateICmpULT(
Add1, ConstantInt::getSigned(IntTy, -static_cast<int64_t>(BitWidth)));
Builder.CreateCondBr(Cmp3, IfThen5, IfEnd9);
// if.then5:
Builder.SetInsertPoint(IfThen5);
Value *PosInf = Builder.CreateXor(NegOne, NegInf);
Value *Cond8 = Builder.CreateSelect(PosOrNeg, PosInf, NegInf);
Builder.CreateBr(End);
// if.end9:
Builder.SetInsertPoint(IfEnd9);
Value *Cmp10 = Builder.CreateICmpULT(
And2, Builder.getIntN(BitWidth, ExponentBias + FPMantissaWidth));
Builder.CreateCondBr(Cmp10, IfThen12, IfElse);
// if.then12:
Builder.SetInsertPoint(IfThen12);
Value *Sub13 = Builder.CreateSub(
Builder.getIntN(BitWidth, ExponentBias + FPMantissaWidth), And2);
Value *Shr14 = Builder.CreateLShr(Or, Sub13);
Value *Mul = Builder.CreateMul(Shr14, Sign);
Builder.CreateBr(End);
// if.else:
Builder.SetInsertPoint(IfElse);
Value *Sub15 = Builder.CreateAdd(
And2, ConstantInt::getSigned(
IntTy, -static_cast<int64_t>(ExponentBias + FPMantissaWidth)));
Value *Shl = Builder.CreateShl(Or, Sub15);
Value *Mul16 = Builder.CreateMul(Shl, Sign);
Builder.CreateBr(End);
// cleanup:
Builder.SetInsertPoint(End, End->begin());
PHINode *Retval0 = Builder.CreatePHI(FPToI->getType(), 4);
Retval0->addIncoming(Cond8, IfThen5);
Retval0->addIncoming(Mul, IfThen12);
Retval0->addIncoming(Mul16, IfElse);
Retval0->addIncoming(Builder.getIntN(BitWidth, 0), Entry);
FPToI->replaceAllUsesWith(Retval0);
FPToI->dropAllReferences();
FPToI->eraseFromParent();
}
// clang-format off: preserve formatting of the following example
/// Generate code to convert a fp number to integer, replacing S(U)IToFP with
/// the generated code. This currently generates code similarly to compiler-rt's
/// implementations. This implementation has an implicit assumption that integer
/// width is larger than fp.
///
/// An example IR generated from compiler-rt/floatdisf.c looks like below:
/// define dso_local float @__floatdisf(i64 noundef %a) local_unnamed_addr #0 {
/// entry:
/// %cmp = icmp eq i64 %a, 0
/// br i1 %cmp, label %return, label %if.end
///
/// if.end: ; preds = %entry
/// %shr = ashr i64 %a, 63
/// %xor = xor i64 %shr, %a
/// %sub = sub nsw i64 %xor, %shr
/// %0 = tail call i64 @llvm.ctlz.i64(i64 %sub, i1 true), !range !5
/// %cast = trunc i64 %0 to i32
/// %sub1 = sub nuw nsw i32 64, %cast
/// %sub2 = xor i32 %cast, 63
/// %cmp3 = icmp ult i32 %cast, 40
/// br i1 %cmp3, label %if.then4, label %if.else
///
/// if.then4: ; preds = %if.end
/// switch i32 %sub1, label %sw.default [
/// i32 25, label %sw.bb
/// i32 26, label %sw.epilog
/// ]
///
/// sw.bb: ; preds = %if.then4
/// %shl = shl i64 %sub, 1
/// br label %sw.epilog
///
/// sw.default: ; preds = %if.then4
/// %sub5 = sub nsw i64 38, %0
/// %sh_prom = and i64 %sub5, 4294967295
/// %shr6 = lshr i64 %sub, %sh_prom
/// %shr9 = lshr i64 274877906943, %0
/// %and = and i64 %shr9, %sub
/// %cmp10 = icmp ne i64 %and, 0
/// %conv11 = zext i1 %cmp10 to i64
/// %or = or i64 %shr6, %conv11
/// br label %sw.epilog
///
/// sw.epilog: ; preds = %sw.default, %if.then4, %sw.bb
/// %a.addr.0 = phi i64 [ %or, %sw.default ], [ %sub, %if.then4 ], [ %shl, %sw.bb ]
/// %1 = lshr i64 %a.addr.0, 2
/// %2 = and i64 %1, 1
/// %or16 = or i64 %2, %a.addr.0
/// %inc = add nsw i64 %or16, 1
/// %3 = and i64 %inc, 67108864
/// %tobool.not = icmp eq i64 %3, 0
/// %spec.select.v = select i1 %tobool.not, i64 2, i64 3
/// %spec.select = ashr i64 %inc, %spec.select.v
/// %spec.select56 = select i1 %tobool.not, i32 %sub2, i32 %sub1
/// br label %if.end26
///
/// if.else: ; preds = %if.end
/// %sub23 = add nuw nsw i64 %0, 4294967256
/// %sh_prom24 = and i64 %sub23, 4294967295
/// %shl25 = shl i64 %sub, %sh_prom24
/// br label %if.end26
///
/// if.end26: ; preds = %sw.epilog, %if.else
/// %a.addr.1 = phi i64 [ %shl25, %if.else ], [ %spec.select, %sw.epilog ]
/// %e.0 = phi i32 [ %sub2, %if.else ], [ %spec.select56, %sw.epilog ]
/// %conv27 = trunc i64 %shr to i32
/// %and28 = and i32 %conv27, -2147483648
/// %add = shl nuw nsw i32 %e.0, 23
/// %shl29 = add nuw nsw i32 %add, 1065353216
/// %conv31 = trunc i64 %a.addr.1 to i32
/// %and32 = and i32 %conv31, 8388607
/// %or30 = or i32 %and32, %and28
/// %or33 = or i32 %or30, %shl29
/// %4 = bitcast i32 %or33 to float
/// br label %return
///
/// return: ; preds = %entry, %if.end26
/// %retval.0 = phi float [ %4, %if.end26 ], [ 0.000000e+00, %entry ]
/// ret float %retval.0
/// }
///
/// Replace integer to fp with generated code.
static void expandIToFP(Instruction *IToFP) {
// clang-format on
IRBuilder<> Builder(IToFP);
auto *IntVal = IToFP->getOperand(0);
IntegerType *IntTy = cast<IntegerType>(IntVal->getType());
unsigned BitWidth = IntVal->getType()->getIntegerBitWidth();
unsigned FPMantissaWidth = IToFP->getType()->getFPMantissaWidth() - 1;
// fp80 conversion is implemented by conversion tp fp128 first following
// a fptrunc to fp80.
FPMantissaWidth = FPMantissaWidth == 63 ? 112 : FPMantissaWidth;
// FIXME: As there is no related builtins added in compliler-rt,
// here currently utilized the fp32 <-> fp16 lib calls to implement.
FPMantissaWidth = FPMantissaWidth == 10 ? 23 : FPMantissaWidth;
FPMantissaWidth = FPMantissaWidth == 7 ? 23 : FPMantissaWidth;
unsigned FloatWidth = PowerOf2Ceil(FPMantissaWidth);
bool IsSigned = IToFP->getOpcode() == Instruction::SIToFP;
assert(BitWidth > FloatWidth && "Unexpected conversion. expandIToFP() "
"assumes integer width is larger than fp.");
Value *Temp1 =
Builder.CreateShl(Builder.getIntN(BitWidth, 1),
Builder.getIntN(BitWidth, FPMantissaWidth + 3));
BasicBlock *Entry = Builder.GetInsertBlock();
Function *F = Entry->getParent();
Entry->setName(Twine(Entry->getName(), "itofp-entry"));
BasicBlock *End =
Entry->splitBasicBlock(Builder.GetInsertPoint(), "itofp-return");
BasicBlock *IfEnd =
BasicBlock::Create(Builder.getContext(), "itofp-if-end", F, End);
BasicBlock *IfThen4 =
BasicBlock::Create(Builder.getContext(), "itofp-if-then4", F, End);
BasicBlock *SwBB =
BasicBlock::Create(Builder.getContext(), "itofp-sw-bb", F, End);
BasicBlock *SwDefault =
BasicBlock::Create(Builder.getContext(), "itofp-sw-default", F, End);
BasicBlock *SwEpilog =
BasicBlock::Create(Builder.getContext(), "itofp-sw-epilog", F, End);
BasicBlock *IfThen20 =
BasicBlock::Create(Builder.getContext(), "itofp-if-then20", F, End);
BasicBlock *IfElse =
BasicBlock::Create(Builder.getContext(), "itofp-if-else", F, End);
BasicBlock *IfEnd26 =
BasicBlock::Create(Builder.getContext(), "itofp-if-end26", F, End);
Entry->getTerminator()->eraseFromParent();
Function *CTLZ =
Intrinsic::getOrInsertDeclaration(F->getParent(), Intrinsic::ctlz, IntTy);
ConstantInt *True = Builder.getTrue();
// entry:
Builder.SetInsertPoint(Entry);
Value *Cmp = Builder.CreateICmpEQ(IntVal, ConstantInt::getSigned(IntTy, 0));
Builder.CreateCondBr(Cmp, End, IfEnd);
// if.end:
Builder.SetInsertPoint(IfEnd);
Value *Shr =
Builder.CreateAShr(IntVal, Builder.getIntN(BitWidth, BitWidth - 1));
Value *Xor = Builder.CreateXor(Shr, IntVal);
Value *Sub = Builder.CreateSub(Xor, Shr);
Value *Call = Builder.CreateCall(CTLZ, {IsSigned ? Sub : IntVal, True});
Value *Cast = Builder.CreateTrunc(Call, Builder.getInt32Ty());
int BitWidthNew = FloatWidth == 128 ? BitWidth : 32;
Value *Sub1 = Builder.CreateSub(Builder.getIntN(BitWidthNew, BitWidth),
FloatWidth == 128 ? Call : Cast);
Value *Sub2 = Builder.CreateSub(Builder.getIntN(BitWidthNew, BitWidth - 1),
FloatWidth == 128 ? Call : Cast);
Value *Cmp3 = Builder.CreateICmpSGT(
Sub1, Builder.getIntN(BitWidthNew, FPMantissaWidth + 1));
Builder.CreateCondBr(Cmp3, IfThen4, IfElse);
// if.then4:
Builder.SetInsertPoint(IfThen4);
llvm::SwitchInst *SI = Builder.CreateSwitch(Sub1, SwDefault);
SI->addCase(Builder.getIntN(BitWidthNew, FPMantissaWidth + 2), SwBB);
SI->addCase(Builder.getIntN(BitWidthNew, FPMantissaWidth + 3), SwEpilog);
// sw.bb:
Builder.SetInsertPoint(SwBB);
Value *Shl =
Builder.CreateShl(IsSigned ? Sub : IntVal, Builder.getIntN(BitWidth, 1));
Builder.CreateBr(SwEpilog);
// sw.default:
Builder.SetInsertPoint(SwDefault);
Value *Sub5 = Builder.CreateSub(
Builder.getIntN(BitWidthNew, BitWidth - FPMantissaWidth - 3),
FloatWidth == 128 ? Call : Cast);
Value *ShProm = Builder.CreateZExt(Sub5, IntTy);
Value *Shr6 = Builder.CreateLShr(IsSigned ? Sub : IntVal,
FloatWidth == 128 ? Sub5 : ShProm);
Value *Sub8 =
Builder.CreateAdd(FloatWidth == 128 ? Call : Cast,
Builder.getIntN(BitWidthNew, FPMantissaWidth + 3));
Value *ShProm9 = Builder.CreateZExt(Sub8, IntTy);
Value *Shr9 = Builder.CreateLShr(ConstantInt::getSigned(IntTy, -1),
FloatWidth == 128 ? Sub8 : ShProm9);
Value *And = Builder.CreateAnd(Shr9, IsSigned ? Sub : IntVal);
Value *Cmp10 = Builder.CreateICmpNE(And, Builder.getIntN(BitWidth, 0));
Value *Conv11 = Builder.CreateZExt(Cmp10, IntTy);
Value *Or = Builder.CreateOr(Shr6, Conv11);
Builder.CreateBr(SwEpilog);
// sw.epilog:
Builder.SetInsertPoint(SwEpilog);
PHINode *AAddr0 = Builder.CreatePHI(IntTy, 3);
AAddr0->addIncoming(Or, SwDefault);
AAddr0->addIncoming(IsSigned ? Sub : IntVal, IfThen4);
AAddr0->addIncoming(Shl, SwBB);
Value *A0 = Builder.CreateTrunc(AAddr0, Builder.getInt32Ty());
Value *A1 = Builder.CreateLShr(A0, Builder.getInt32(2));
Value *A2 = Builder.CreateAnd(A1, Builder.getInt32(1));
Value *Conv16 = Builder.CreateZExt(A2, IntTy);
Value *Or17 = Builder.CreateOr(AAddr0, Conv16);
Value *Inc = Builder.CreateAdd(Or17, Builder.getIntN(BitWidth, 1));
Value *Shr18 = nullptr;
if (IsSigned)
Shr18 = Builder.CreateAShr(Inc, Builder.getIntN(BitWidth, 2));
else
Shr18 = Builder.CreateLShr(Inc, Builder.getIntN(BitWidth, 2));
Value *A3 = Builder.CreateAnd(Inc, Temp1, "a3");
Value *PosOrNeg = Builder.CreateICmpEQ(A3, Builder.getIntN(BitWidth, 0));
Value *ExtractT60 = Builder.CreateTrunc(Shr18, Builder.getIntNTy(FloatWidth));
Value *Extract63 = Builder.CreateLShr(Shr18, Builder.getIntN(BitWidth, 32));
Value *ExtractT64 = nullptr;
if (FloatWidth > 80)
ExtractT64 = Builder.CreateTrunc(Sub2, Builder.getInt64Ty());
else
ExtractT64 = Builder.CreateTrunc(Extract63, Builder.getInt32Ty());
Builder.CreateCondBr(PosOrNeg, IfEnd26, IfThen20);
// if.then20
Builder.SetInsertPoint(IfThen20);
Value *Shr21 = nullptr;
if (IsSigned)
Shr21 = Builder.CreateAShr(Inc, Builder.getIntN(BitWidth, 3));
else
Shr21 = Builder.CreateLShr(Inc, Builder.getIntN(BitWidth, 3));
Value *ExtractT = Builder.CreateTrunc(Shr21, Builder.getIntNTy(FloatWidth));
Value *Extract = Builder.CreateLShr(Shr21, Builder.getIntN(BitWidth, 32));
Value *ExtractT62 = nullptr;
if (FloatWidth > 80)
ExtractT62 = Builder.CreateTrunc(Sub1, Builder.getInt64Ty());
else
ExtractT62 = Builder.CreateTrunc(Extract, Builder.getInt32Ty());
Builder.CreateBr(IfEnd26);
// if.else:
Builder.SetInsertPoint(IfElse);
Value *Sub24 = Builder.CreateAdd(
FloatWidth == 128 ? Call : Cast,
ConstantInt::getSigned(Builder.getIntNTy(BitWidthNew),
-(BitWidth - FPMantissaWidth - 1)));
Value *ShProm25 = Builder.CreateZExt(Sub24, IntTy);
Value *Shl26 = Builder.CreateShl(IsSigned ? Sub : IntVal,
FloatWidth == 128 ? Sub24 : ShProm25);
Value *ExtractT61 = Builder.CreateTrunc(Shl26, Builder.getIntNTy(FloatWidth));
Value *Extract65 = Builder.CreateLShr(Shl26, Builder.getIntN(BitWidth, 32));
Value *ExtractT66 = nullptr;
if (FloatWidth > 80)
ExtractT66 = Builder.CreateTrunc(Sub2, Builder.getInt64Ty());
else
ExtractT66 = Builder.CreateTrunc(Extract65, Builder.getInt32Ty());
Builder.CreateBr(IfEnd26);
// if.end26:
Builder.SetInsertPoint(IfEnd26);
PHINode *AAddr1Off0 = Builder.CreatePHI(Builder.getIntNTy(FloatWidth), 3);
AAddr1Off0->addIncoming(ExtractT, IfThen20);
AAddr1Off0->addIncoming(ExtractT60, SwEpilog);
AAddr1Off0->addIncoming(ExtractT61, IfElse);
PHINode *AAddr1Off32 = nullptr;
if (FloatWidth > 32) {
AAddr1Off32 =
Builder.CreatePHI(Builder.getIntNTy(FloatWidth > 80 ? 64 : 32), 3);
AAddr1Off32->addIncoming(ExtractT62, IfThen20);
AAddr1Off32->addIncoming(ExtractT64, SwEpilog);
AAddr1Off32->addIncoming(ExtractT66, IfElse);
}
PHINode *E0 = nullptr;
if (FloatWidth <= 80) {
E0 = Builder.CreatePHI(Builder.getIntNTy(BitWidthNew), 3);
E0->addIncoming(Sub1, IfThen20);
E0->addIncoming(Sub2, SwEpilog);
E0->addIncoming(Sub2, IfElse);
}
Value *And29 = nullptr;
if (FloatWidth > 80) {
Value *Temp2 = Builder.CreateShl(Builder.getIntN(BitWidth, 1),
Builder.getIntN(BitWidth, 63));
And29 = Builder.CreateAnd(Shr, Temp2, "and29");
} else {
Value *Conv28 = Builder.CreateTrunc(Shr, Builder.getInt32Ty());
And29 = Builder.CreateAnd(
Conv28, ConstantInt::getSigned(Builder.getInt32Ty(), 0x80000000));
}
unsigned TempMod = FPMantissaWidth % 32;
Value *And34 = nullptr;
Value *Shl30 = nullptr;
if (FloatWidth > 80) {
TempMod += 32;
Value *Add = Builder.CreateShl(AAddr1Off32, Builder.getInt64(TempMod));
Shl30 = Builder.CreateAdd(
Add, Builder.getInt64(((1ull << (62ull - TempMod)) - 1ull) << TempMod));
And34 = Builder.CreateZExt(Shl30, Builder.getInt128Ty());
} else {
Value *Add = Builder.CreateShl(E0, Builder.getInt32(TempMod));
Shl30 = Builder.CreateAdd(
Add, Builder.getInt32(((1 << (30 - TempMod)) - 1) << TempMod));
And34 = Builder.CreateAnd(FloatWidth > 32 ? AAddr1Off32 : AAddr1Off0,
Builder.getInt32((1 << TempMod) - 1));
}
Value *Or35 = nullptr;
if (FloatWidth > 80) {
Value *And29Trunc = Builder.CreateTrunc(And29, Builder.getInt128Ty());
Value *Or31 = Builder.CreateOr(And29Trunc, And34);
Value *Or34 = Builder.CreateShl(Or31, Builder.getIntN(128, 64));
Value *Temp3 = Builder.CreateShl(Builder.getIntN(128, 1),
Builder.getIntN(128, FPMantissaWidth));
Value *Temp4 = Builder.CreateSub(Temp3, Builder.getIntN(128, 1));
Value *A6 = Builder.CreateAnd(AAddr1Off0, Temp4);
Or35 = Builder.CreateOr(Or34, A6);
} else {
Value *Or31 = Builder.CreateOr(And34, And29);
Or35 = Builder.CreateOr(IsSigned ? Or31 : And34, Shl30);
}
Value *A4 = nullptr;
if (IToFP->getType()->isDoubleTy()) {
Value *ZExt1 = Builder.CreateZExt(Or35, Builder.getIntNTy(FloatWidth));
Value *Shl1 = Builder.CreateShl(ZExt1, Builder.getIntN(FloatWidth, 32));
Value *And1 =
Builder.CreateAnd(AAddr1Off0, Builder.getIntN(FloatWidth, 0xFFFFFFFF));
Value *Or1 = Builder.CreateOr(Shl1, And1);
A4 = Builder.CreateBitCast(Or1, IToFP->getType());
} else if (IToFP->getType()->isX86_FP80Ty()) {
Value *A40 =
Builder.CreateBitCast(Or35, Type::getFP128Ty(Builder.getContext()));
A4 = Builder.CreateFPTrunc(A40, IToFP->getType());
} else if (IToFP->getType()->isHalfTy() || IToFP->getType()->isBFloatTy()) {
// Deal with "half" situation. This is a workaround since we don't have
// floattihf.c currently as referring.
Value *A40 =
Builder.CreateBitCast(Or35, Type::getFloatTy(Builder.getContext()));
A4 = Builder.CreateFPTrunc(A40, IToFP->getType());
} else // float type
A4 = Builder.CreateBitCast(Or35, IToFP->getType());
Builder.CreateBr(End);
// return:
Builder.SetInsertPoint(End, End->begin());
PHINode *Retval0 = Builder.CreatePHI(IToFP->getType(), 2);
Retval0->addIncoming(A4, IfEnd26);
Retval0->addIncoming(ConstantFP::getZero(IToFP->getType(), false), Entry);
IToFP->replaceAllUsesWith(Retval0);
IToFP->dropAllReferences();
IToFP->eraseFromParent();
}
static void scalarize(Instruction *I, SmallVectorImpl<Instruction *> &Replace) {
VectorType *VTy = cast<FixedVectorType>(I->getType());
IRBuilder<> Builder(I);
unsigned NumElements = VTy->getElementCount().getFixedValue();
Value *Result = PoisonValue::get(VTy);
for (unsigned Idx = 0; Idx < NumElements; ++Idx) {
Value *Ext = Builder.CreateExtractElement(I->getOperand(0), Idx);
Value *Cast = Builder.CreateCast(cast<CastInst>(I)->getOpcode(), Ext,
I->getType()->getScalarType());
Result = Builder.CreateInsertElement(Result, Cast, Idx);
if (isa<Instruction>(Cast))
Replace.push_back(cast<Instruction>(Cast));
}
I->replaceAllUsesWith(Result);
I->dropAllReferences();
I->eraseFromParent();
}
static bool runImpl(Function &F, const TargetLowering &TLI) {
SmallVector<Instruction *, 4> Replace;
SmallVector<Instruction *, 4> ReplaceVector;
bool Modified = false;
unsigned MaxLegalFpConvertBitWidth =
TLI.getMaxLargeFPConvertBitWidthSupported();
if (ExpandFpConvertBits != llvm::IntegerType::MAX_INT_BITS)
MaxLegalFpConvertBitWidth = ExpandFpConvertBits;
if (MaxLegalFpConvertBitWidth >= llvm::IntegerType::MAX_INT_BITS)
return false;
for (auto &I : instructions(F)) {
switch (I.getOpcode()) {
case Instruction::FPToUI:
case Instruction::FPToSI: {
// TODO: This pass doesn't handle scalable vectors.
if (I.getOperand(0)->getType()->isScalableTy())
continue;
auto *IntTy = cast<IntegerType>(I.getType()->getScalarType());
if (IntTy->getIntegerBitWidth() <= MaxLegalFpConvertBitWidth)
continue;
if (I.getOperand(0)->getType()->isVectorTy())
ReplaceVector.push_back(&I);
else
Replace.push_back(&I);
Modified = true;
break;
}
case Instruction::UIToFP:
case Instruction::SIToFP: {
// TODO: This pass doesn't handle scalable vectors.
if (I.getOperand(0)->getType()->isScalableTy())
continue;
auto *IntTy =
cast<IntegerType>(I.getOperand(0)->getType()->getScalarType());
if (IntTy->getIntegerBitWidth() <= MaxLegalFpConvertBitWidth)
continue;
if (I.getOperand(0)->getType()->isVectorTy())
ReplaceVector.push_back(&I);
else
Replace.push_back(&I);
Modified = true;
break;
}
default:
break;
}
}
while (!ReplaceVector.empty()) {
Instruction *I = ReplaceVector.pop_back_val();
scalarize(I, Replace);
}
if (Replace.empty())
return false;
while (!Replace.empty()) {
Instruction *I = Replace.pop_back_val();
if (I->getOpcode() == Instruction::FPToUI ||
I->getOpcode() == Instruction::FPToSI) {
expandFPToI(I);
} else {
expandIToFP(I);
}
}
return Modified;
}
namespace {
class ExpandFpLegacyPass : public FunctionPass {
public:
static char ID;
ExpandFpLegacyPass() : FunctionPass(ID) {
initializeExpandFpLegacyPassPass(*PassRegistry::getPassRegistry());
}
bool runOnFunction(Function &F) override {
auto *TM = &getAnalysis<TargetPassConfig>().getTM<TargetMachine>();
auto *TLI = TM->getSubtargetImpl(F)->getTargetLowering();
return runImpl(F, *TLI);
}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<TargetPassConfig>();
AU.addPreserved<AAResultsWrapperPass>();
AU.addPreserved<GlobalsAAWrapperPass>();
}
};
} // namespace
PreservedAnalyses ExpandFpPass::run(Function &F, FunctionAnalysisManager &FAM) {
const TargetSubtargetInfo *STI = TM->getSubtargetImpl(F);
return runImpl(F, *STI->getTargetLowering()) ? PreservedAnalyses::none()
: PreservedAnalyses::all();
}
char ExpandFpLegacyPass::ID = 0;
INITIALIZE_PASS_BEGIN(ExpandFpLegacyPass, "expand-fp",
"Expand certain fp instructions", false, false)
INITIALIZE_PASS_END(ExpandFpLegacyPass, "expand-fp", "Expand fp", false, false)
FunctionPass *llvm::createExpandFpPass() { return new ExpandFpLegacyPass(); }