[llvm-commits] [llvm] r92468 - in /llvm/trunk/lib/Transforms/InstCombine: CMakeLists.txt InstCombine.h InstCombineCasts.cpp InstructionCombining.cpp
Chris Lattner
sabre at nondot.org
Sun Jan 3 23:53:59 PST 2010
Author: lattner
Date: Mon Jan 4 01:53:58 2010
New Revision: 92468
URL: http://llvm.org/viewvc/llvm-project?rev=92468&view=rev
Log:
split 943 lines of instcombine out to a new InstCombineCasts.cpp
file. InstructionCombining.cpp is now down to a svelte 9300 lines :)
Added:
llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp
Modified:
llvm/trunk/lib/Transforms/InstCombine/CMakeLists.txt
llvm/trunk/lib/Transforms/InstCombine/InstCombine.h
llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
Modified: llvm/trunk/lib/Transforms/InstCombine/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/CMakeLists.txt?rev=92468&r1=92467&r2=92468&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/CMakeLists.txt (original)
+++ llvm/trunk/lib/Transforms/InstCombine/CMakeLists.txt Mon Jan 4 01:53:58 2010
@@ -1,5 +1,6 @@
add_llvm_library(LLVMInstCombine
InstructionCombining.cpp
+ InstCombineCasts.cpp
InstCombineCompares.cpp
InstCombineSimplifyDemanded.cpp
)
Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombine.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombine.h?rev=92468&r1=92467&r2=92468&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombine.h (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombine.h Mon Jan 4 01:53:58 2010
@@ -193,7 +193,17 @@
Instruction *visitInstruction(Instruction &I) { return 0; }
private:
+ bool ShouldChangeType(const Type *From, const Type *To) const;
Value *dyn_castNegVal(Value *V) const;
+ const Type *FindElementAtOffset(const Type *Ty, int64_t Offset,
+ SmallVectorImpl<Value*> &NewIndices);
+ Instruction *FoldOpIntoSelect(Instruction &Op, SelectInst *SI);
+
+ /// ValueRequiresCast - Return true if the cast from "V to Ty" actually
+ /// results in any code being generated. It does not require codegen if V is
+ /// simple enough or if the cast can be folded into other casts.
+ bool ValueRequiresCast(Instruction::CastOps opcode,const Value *V,
+ const Type *Ty);
Instruction *visitCallSite(CallSite CS);
bool transformConstExprCastCall(CallSite CS);
Added: llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp?rev=92468&view=auto
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp (added)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineCasts.cpp Mon Jan 4 01:53:58 2010
@@ -0,0 +1,943 @@
+//===- InstCombineCasts.cpp -----------------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the visit functions for cast operations.
+//
+//===----------------------------------------------------------------------===//
+
+#include "InstCombine.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Support/PatternMatch.h"
+using namespace llvm;
+using namespace PatternMatch;
+
+// FIXME: InstCombiner::EvaluateInDifferentType!
+
+
+/// This function is a wrapper around CastInst::isEliminableCastPair. It
+/// simply extracts arguments and returns what that function returns.
+static Instruction::CastOps
+isEliminableCastPair(
+ const CastInst *CI, ///< The first cast instruction
+ unsigned opcode, ///< The opcode of the second cast instruction
+ const Type *DstTy, ///< The target type for the second cast instruction
+ TargetData *TD ///< The target data for pointer size
+) {
+
+ const Type *SrcTy = CI->getOperand(0)->getType(); // A from above
+ const Type *MidTy = CI->getType(); // B from above
+
+ // Get the opcodes of the two Cast instructions
+ Instruction::CastOps firstOp = Instruction::CastOps(CI->getOpcode());
+ Instruction::CastOps secondOp = Instruction::CastOps(opcode);
+
+ unsigned Res = CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy,
+ DstTy,
+ TD ? TD->getIntPtrType(CI->getContext()) : 0);
+
+ // We don't want to form an inttoptr or ptrtoint that converts to an integer
+ // type that differs from the pointer size.
+ if ((Res == Instruction::IntToPtr &&
+ (!TD || SrcTy != TD->getIntPtrType(CI->getContext()))) ||
+ (Res == Instruction::PtrToInt &&
+ (!TD || DstTy != TD->getIntPtrType(CI->getContext()))))
+ Res = 0;
+
+ return Instruction::CastOps(Res);
+}
+
+/// ValueRequiresCast - Return true if the cast from "V to Ty" actually results
+/// in any code being generated. It does not require codegen if V is simple
+/// enough or if the cast can be folded into other casts.
+bool InstCombiner::ValueRequiresCast(Instruction::CastOps opcode,const Value *V,
+ const Type *Ty) {
+ if (V->getType() == Ty || isa<Constant>(V)) return false;
+
+ // If this is another cast that can be eliminated, it isn't codegen either.
+ if (const CastInst *CI = dyn_cast<CastInst>(V))
+ if (isEliminableCastPair(CI, opcode, Ty, TD))
+ return false;
+ return true;
+}
+
+
+/// @brief Implement the transforms common to all CastInst visitors.
+Instruction *InstCombiner::commonCastTransforms(CastInst &CI) {
+ Value *Src = CI.getOperand(0);
+
+ // Many cases of "cast of a cast" are eliminable. If it's eliminable we just
+ // eliminate it now.
+ if (CastInst *CSrc = dyn_cast<CastInst>(Src)) { // A->B->C cast
+ if (Instruction::CastOps opc =
+ isEliminableCastPair(CSrc, CI.getOpcode(), CI.getType(), TD)) {
+ // The first cast (CSrc) is eliminable so we need to fix up or replace
+ // the second cast (CI). CSrc will then have a good chance of being dead.
+ return CastInst::Create(opc, CSrc->getOperand(0), CI.getType());
+ }
+ }
+
+ // If we are casting a select then fold the cast into the select
+ if (SelectInst *SI = dyn_cast<SelectInst>(Src))
+ if (Instruction *NV = FoldOpIntoSelect(CI, SI))
+ return NV;
+
+ // If we are casting a PHI then fold the cast into the PHI
+ if (isa<PHINode>(Src)) {
+ // We don't do this if this would create a PHI node with an illegal type if
+ // it is currently legal.
+ if (!isa<IntegerType>(Src->getType()) ||
+ !isa<IntegerType>(CI.getType()) ||
+ ShouldChangeType(CI.getType(), Src->getType()))
+ if (Instruction *NV = FoldOpIntoPhi(CI))
+ return NV;
+ }
+
+ return 0;
+}
+
+/// @brief Implement the transforms for cast of pointer (bitcast/ptrtoint)
+Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) {
+ Value *Src = CI.getOperand(0);
+
+ if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Src)) {
+ // If casting the result of a getelementptr instruction with no offset, turn
+ // this into a cast of the original pointer!
+ if (GEP->hasAllZeroIndices()) {
+ // Changing the cast operand is usually not a good idea but it is safe
+ // here because the pointer operand is being replaced with another
+ // pointer operand so the opcode doesn't need to change.
+ Worklist.Add(GEP);
+ CI.setOperand(0, GEP->getOperand(0));
+ return &CI;
+ }
+
+ // If the GEP has a single use, and the base pointer is a bitcast, and the
+ // GEP computes a constant offset, see if we can convert these three
+ // instructions into fewer. This typically happens with unions and other
+ // non-type-safe code.
+ if (TD && GEP->hasOneUse() && isa<BitCastInst>(GEP->getOperand(0))) {
+ if (GEP->hasAllConstantIndices()) {
+ // We are guaranteed to get a constant from EmitGEPOffset.
+ ConstantInt *OffsetV = cast<ConstantInt>(EmitGEPOffset(GEP));
+ int64_t Offset = OffsetV->getSExtValue();
+
+ // Get the base pointer input of the bitcast, and the type it points to.
+ Value *OrigBase = cast<BitCastInst>(GEP->getOperand(0))->getOperand(0);
+ const Type *GEPIdxTy =
+ cast<PointerType>(OrigBase->getType())->getElementType();
+ SmallVector<Value*, 8> NewIndices;
+ if (FindElementAtOffset(GEPIdxTy, Offset, NewIndices)) {
+ // If we were able to index down into an element, create the GEP
+ // and bitcast the result. This eliminates one bitcast, potentially
+ // two.
+ Value *NGEP = cast<GEPOperator>(GEP)->isInBounds() ?
+ Builder->CreateInBoundsGEP(OrigBase,
+ NewIndices.begin(), NewIndices.end()) :
+ Builder->CreateGEP(OrigBase, NewIndices.begin(), NewIndices.end());
+ NGEP->takeName(GEP);
+
+ if (isa<BitCastInst>(CI))
+ return new BitCastInst(NGEP, CI.getType());
+ assert(isa<PtrToIntInst>(CI));
+ return new PtrToIntInst(NGEP, CI.getType());
+ }
+ }
+ }
+ }
+
+ return commonCastTransforms(CI);
+}
+
+/// commonIntCastTransforms - This function implements the common transforms
+/// for trunc, zext, and sext.
+Instruction *InstCombiner::commonIntCastTransforms(CastInst &CI) {
+ if (Instruction *Result = commonCastTransforms(CI))
+ return Result;
+
+ Value *Src = CI.getOperand(0);
+ const Type *SrcTy = Src->getType();
+ const Type *DestTy = CI.getType();
+ uint32_t SrcBitSize = SrcTy->getScalarSizeInBits();
+ uint32_t DestBitSize = DestTy->getScalarSizeInBits();
+
+ // See if we can simplify any instructions used by the LHS whose sole
+ // purpose is to compute bits we don't care about.
+ if (SimplifyDemandedInstructionBits(CI))
+ return &CI;
+
+ // If the source isn't an instruction or has more than one use then we
+ // can't do anything more.
+ Instruction *SrcI = dyn_cast<Instruction>(Src);
+ if (!SrcI || !Src->hasOneUse())
+ return 0;
+
+ // Attempt to propagate the cast into the instruction for int->int casts.
+ int NumCastsRemoved = 0;
+ // Only do this if the dest type is a simple type, don't convert the
+ // expression tree to something weird like i93 unless the source is also
+ // strange.
+ if ((isa<VectorType>(DestTy) ||
+ ShouldChangeType(SrcI->getType(), DestTy)) &&
+ CanEvaluateInDifferentType(SrcI, DestTy,
+ CI.getOpcode(), NumCastsRemoved)) {
+ // If this cast is a truncate, evaluting in a different type always
+ // eliminates the cast, so it is always a win. If this is a zero-extension,
+ // we need to do an AND to maintain the clear top-part of the computation,
+ // so we require that the input have eliminated at least one cast. If this
+ // is a sign extension, we insert two new casts (to do the extension) so we
+ // require that two casts have been eliminated.
+ bool DoXForm = false;
+ bool JustReplace = false;
+ switch (CI.getOpcode()) {
+ default:
+ // All the others use floating point so we shouldn't actually
+ // get here because of the check above.
+ llvm_unreachable("Unknown cast type");
+ case Instruction::Trunc:
+ DoXForm = true;
+ break;
+ case Instruction::ZExt: {
+ DoXForm = NumCastsRemoved >= 1;
+
+ if (!DoXForm && 0) {
+ // If it's unnecessary to issue an AND to clear the high bits, it's
+ // always profitable to do this xform.
+ Value *TryRes = EvaluateInDifferentType(SrcI, DestTy, false);
+ APInt Mask(APInt::getBitsSet(DestBitSize, SrcBitSize, DestBitSize));
+ if (MaskedValueIsZero(TryRes, Mask))
+ return ReplaceInstUsesWith(CI, TryRes);
+
+ if (Instruction *TryI = dyn_cast<Instruction>(TryRes))
+ if (TryI->use_empty())
+ EraseInstFromFunction(*TryI);
+ }
+ break;
+ }
+ case Instruction::SExt: {
+ DoXForm = NumCastsRemoved >= 2;
+ if (!DoXForm && !isa<TruncInst>(SrcI) && 0) {
+ // If we do not have to emit the truncate + sext pair, then it's always
+ // profitable to do this xform.
+ //
+ // It's not safe to eliminate the trunc + sext pair if one of the
+ // eliminated cast is a truncate. e.g.
+ // t2 = trunc i32 t1 to i16
+ // t3 = sext i16 t2 to i32
+ // !=
+ // i32 t1
+ Value *TryRes = EvaluateInDifferentType(SrcI, DestTy, true);
+ unsigned NumSignBits = ComputeNumSignBits(TryRes);
+ if (NumSignBits > (DestBitSize - SrcBitSize))
+ return ReplaceInstUsesWith(CI, TryRes);
+
+ if (Instruction *TryI = dyn_cast<Instruction>(TryRes))
+ if (TryI->use_empty())
+ EraseInstFromFunction(*TryI);
+ }
+ break;
+ }
+ }
+
+ if (DoXForm) {
+ DEBUG(errs() << "ICE: EvaluateInDifferentType converting expression type"
+ " to avoid cast: " << CI);
+ Value *Res = EvaluateInDifferentType(SrcI, DestTy,
+ CI.getOpcode() == Instruction::SExt);
+ if (JustReplace)
+ // Just replace this cast with the result.
+ return ReplaceInstUsesWith(CI, Res);
+
+ assert(Res->getType() == DestTy);
+ switch (CI.getOpcode()) {
+ default: llvm_unreachable("Unknown cast type!");
+ case Instruction::Trunc:
+ // Just replace this cast with the result.
+ return ReplaceInstUsesWith(CI, Res);
+ case Instruction::ZExt: {
+ assert(SrcBitSize < DestBitSize && "Not a zext?");
+
+ // If the high bits are already zero, just replace this cast with the
+ // result.
+ APInt Mask(APInt::getBitsSet(DestBitSize, SrcBitSize, DestBitSize));
+ if (MaskedValueIsZero(Res, Mask))
+ return ReplaceInstUsesWith(CI, Res);
+
+ // We need to emit an AND to clear the high bits.
+ Constant *C = ConstantInt::get(CI.getContext(),
+ APInt::getLowBitsSet(DestBitSize, SrcBitSize));
+ return BinaryOperator::CreateAnd(Res, C);
+ }
+ case Instruction::SExt: {
+ // If the high bits are already filled with sign bit, just replace this
+ // cast with the result.
+ unsigned NumSignBits = ComputeNumSignBits(Res);
+ if (NumSignBits > (DestBitSize - SrcBitSize))
+ return ReplaceInstUsesWith(CI, Res);
+
+ // We need to emit a cast to truncate, then a cast to sext.
+ return new SExtInst(Builder->CreateTrunc(Res, Src->getType()), DestTy);
+ }
+ }
+ }
+ }
+
+ Value *Op0 = SrcI->getNumOperands() > 0 ? SrcI->getOperand(0) : 0;
+ Value *Op1 = SrcI->getNumOperands() > 1 ? SrcI->getOperand(1) : 0;
+
+ switch (SrcI->getOpcode()) {
+ case Instruction::Add:
+ case Instruction::Mul:
+ case Instruction::And:
+ case Instruction::Or:
+ case Instruction::Xor:
+ // If we are discarding information, rewrite.
+ if (DestBitSize < SrcBitSize && DestBitSize != 1) {
+ // Don't insert two casts unless at least one can be eliminated.
+ if (!ValueRequiresCast(CI.getOpcode(), Op1, DestTy) ||
+ !ValueRequiresCast(CI.getOpcode(), Op0, DestTy)) {
+ Value *Op0c = Builder->CreateTrunc(Op0, DestTy, Op0->getName());
+ Value *Op1c = Builder->CreateTrunc(Op1, DestTy, Op1->getName());
+ return BinaryOperator::Create(
+ cast<BinaryOperator>(SrcI)->getOpcode(), Op0c, Op1c);
+ }
+ }
+
+ // cast (xor bool X, true) to int --> xor (cast bool X to int), 1
+ if (isa<ZExtInst>(CI) && SrcBitSize == 1 &&
+ SrcI->getOpcode() == Instruction::Xor &&
+ Op1 == ConstantInt::getTrue(CI.getContext()) &&
+ (!Op0->hasOneUse() || !isa<CmpInst>(Op0))) {
+ Value *New = Builder->CreateZExt(Op0, DestTy, Op0->getName());
+ return BinaryOperator::CreateXor(New,
+ ConstantInt::get(CI.getType(), 1));
+ }
+ break;
+
+ case Instruction::Shl: {
+ // Canonicalize trunc inside shl, if we can.
+ ConstantInt *CI = dyn_cast<ConstantInt>(Op1);
+ if (CI && DestBitSize < SrcBitSize &&
+ CI->getLimitedValue(DestBitSize) < DestBitSize) {
+ Value *Op0c = Builder->CreateTrunc(Op0, DestTy, Op0->getName());
+ Value *Op1c = Builder->CreateTrunc(Op1, DestTy, Op1->getName());
+ return BinaryOperator::CreateShl(Op0c, Op1c);
+ }
+ break;
+ }
+ }
+ return 0;
+}
+
+
+Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
+ if (Instruction *Result = commonIntCastTransforms(CI))
+ return Result;
+
+ Value *Src = CI.getOperand(0);
+ const Type *Ty = CI.getType();
+ uint32_t DestBitWidth = Ty->getScalarSizeInBits();
+ uint32_t SrcBitWidth = Src->getType()->getScalarSizeInBits();
+
+ // Canonicalize trunc x to i1 -> (icmp ne (and x, 1), 0)
+ if (DestBitWidth == 1) {
+ Constant *One = ConstantInt::get(Src->getType(), 1);
+ Src = Builder->CreateAnd(Src, One, "tmp");
+ Value *Zero = Constant::getNullValue(Src->getType());
+ return new ICmpInst(ICmpInst::ICMP_NE, Src, Zero);
+ }
+
+ // Optimize trunc(lshr(), c) to pull the shift through the truncate.
+ ConstantInt *ShAmtV = 0;
+ Value *ShiftOp = 0;
+ if (Src->hasOneUse() &&
+ match(Src, m_LShr(m_Value(ShiftOp), m_ConstantInt(ShAmtV)))) {
+ uint32_t ShAmt = ShAmtV->getLimitedValue(SrcBitWidth);
+
+ // Get a mask for the bits shifting in.
+ APInt Mask(APInt::getLowBitsSet(SrcBitWidth, ShAmt).shl(DestBitWidth));
+ if (MaskedValueIsZero(ShiftOp, Mask)) {
+ if (ShAmt >= DestBitWidth) // All zeros.
+ return ReplaceInstUsesWith(CI, Constant::getNullValue(Ty));
+
+ // Okay, we can shrink this. Truncate the input, then return a new
+ // shift.
+ Value *V1 = Builder->CreateTrunc(ShiftOp, Ty, ShiftOp->getName());
+ Value *V2 = ConstantExpr::getTrunc(ShAmtV, Ty);
+ return BinaryOperator::CreateLShr(V1, V2);
+ }
+ }
+
+ return 0;
+}
+
+/// transformZExtICmp - Transform (zext icmp) to bitwise / integer operations
+/// in order to eliminate the icmp.
+Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, Instruction &CI,
+ bool DoXform) {
+ // If we are just checking for a icmp eq of a single bit and zext'ing it
+ // to an integer, then shift the bit to the appropriate place and then
+ // cast to integer to avoid the comparison.
+ if (ConstantInt *Op1C = dyn_cast<ConstantInt>(ICI->getOperand(1))) {
+ const APInt &Op1CV = Op1C->getValue();
+
+ // zext (x <s 0) to i32 --> x>>u31 true if signbit set.
+ // zext (x >s -1) to i32 --> (x>>u31)^1 true if signbit clear.
+ if ((ICI->getPredicate() == ICmpInst::ICMP_SLT && Op1CV == 0) ||
+ (ICI->getPredicate() == ICmpInst::ICMP_SGT &&Op1CV.isAllOnesValue())) {
+ if (!DoXform) return ICI;
+
+ Value *In = ICI->getOperand(0);
+ Value *Sh = ConstantInt::get(In->getType(),
+ In->getType()->getScalarSizeInBits()-1);
+ In = Builder->CreateLShr(In, Sh, In->getName()+".lobit");
+ if (In->getType() != CI.getType())
+ In = Builder->CreateIntCast(In, CI.getType(), false/*ZExt*/, "tmp");
+
+ if (ICI->getPredicate() == ICmpInst::ICMP_SGT) {
+ Constant *One = ConstantInt::get(In->getType(), 1);
+ In = Builder->CreateXor(In, One, In->getName()+".not");
+ }
+
+ return ReplaceInstUsesWith(CI, In);
+ }
+
+
+
+ // zext (X == 0) to i32 --> X^1 iff X has only the low bit set.
+ // zext (X == 0) to i32 --> (X>>1)^1 iff X has only the 2nd bit set.
+ // zext (X == 1) to i32 --> X iff X has only the low bit set.
+ // zext (X == 2) to i32 --> X>>1 iff X has only the 2nd bit set.
+ // zext (X != 0) to i32 --> X iff X has only the low bit set.
+ // zext (X != 0) to i32 --> X>>1 iff X has only the 2nd bit set.
+ // zext (X != 1) to i32 --> X^1 iff X has only the low bit set.
+ // zext (X != 2) to i32 --> (X>>1)^1 iff X has only the 2nd bit set.
+ if ((Op1CV == 0 || Op1CV.isPowerOf2()) &&
+ // This only works for EQ and NE
+ ICI->isEquality()) {
+ // If Op1C some other power of two, convert:
+ uint32_t BitWidth = Op1C->getType()->getBitWidth();
+ APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
+ APInt TypeMask(APInt::getAllOnesValue(BitWidth));
+ ComputeMaskedBits(ICI->getOperand(0), TypeMask, KnownZero, KnownOne);
+
+ APInt KnownZeroMask(~KnownZero);
+ if (KnownZeroMask.isPowerOf2()) { // Exactly 1 possible 1?
+ if (!DoXform) return ICI;
+
+ bool isNE = ICI->getPredicate() == ICmpInst::ICMP_NE;
+ if (Op1CV != 0 && (Op1CV != KnownZeroMask)) {
+ // (X&4) == 2 --> false
+ // (X&4) != 2 --> true
+ Constant *Res = ConstantInt::get(Type::getInt1Ty(CI.getContext()),
+ isNE);
+ Res = ConstantExpr::getZExt(Res, CI.getType());
+ return ReplaceInstUsesWith(CI, Res);
+ }
+
+ uint32_t ShiftAmt = KnownZeroMask.logBase2();
+ Value *In = ICI->getOperand(0);
+ if (ShiftAmt) {
+ // Perform a logical shr by shiftamt.
+ // Insert the shift to put the result in the low bit.
+ In = Builder->CreateLShr(In, ConstantInt::get(In->getType(),ShiftAmt),
+ In->getName()+".lobit");
+ }
+
+ if ((Op1CV != 0) == isNE) { // Toggle the low bit.
+ Constant *One = ConstantInt::get(In->getType(), 1);
+ In = Builder->CreateXor(In, One, "tmp");
+ }
+
+ if (CI.getType() == In->getType())
+ return ReplaceInstUsesWith(CI, In);
+ else
+ return CastInst::CreateIntegerCast(In, CI.getType(), false/*ZExt*/);
+ }
+ }
+ }
+
+ // icmp ne A, B is equal to xor A, B when A and B only really have one bit.
+ // It is also profitable to transform icmp eq into not(xor(A, B)) because that
+ // may lead to additional simplifications.
+ if (ICI->isEquality() && CI.getType() == ICI->getOperand(0)->getType()) {
+ if (const IntegerType *ITy = dyn_cast<IntegerType>(CI.getType())) {
+ uint32_t BitWidth = ITy->getBitWidth();
+ Value *LHS = ICI->getOperand(0);
+ Value *RHS = ICI->getOperand(1);
+
+ APInt KnownZeroLHS(BitWidth, 0), KnownOneLHS(BitWidth, 0);
+ APInt KnownZeroRHS(BitWidth, 0), KnownOneRHS(BitWidth, 0);
+ APInt TypeMask(APInt::getAllOnesValue(BitWidth));
+ ComputeMaskedBits(LHS, TypeMask, KnownZeroLHS, KnownOneLHS);
+ ComputeMaskedBits(RHS, TypeMask, KnownZeroRHS, KnownOneRHS);
+
+ if (KnownZeroLHS == KnownZeroRHS && KnownOneLHS == KnownOneRHS) {
+ APInt KnownBits = KnownZeroLHS | KnownOneLHS;
+ APInt UnknownBit = ~KnownBits;
+ if (UnknownBit.countPopulation() == 1) {
+ if (!DoXform) return ICI;
+
+ Value *Result = Builder->CreateXor(LHS, RHS);
+
+ // Mask off any bits that are set and won't be shifted away.
+ if (KnownOneLHS.uge(UnknownBit))
+ Result = Builder->CreateAnd(Result,
+ ConstantInt::get(ITy, UnknownBit));
+
+ // Shift the bit we're testing down to the lsb.
+ Result = Builder->CreateLShr(
+ Result, ConstantInt::get(ITy, UnknownBit.countTrailingZeros()));
+
+ if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
+ Result = Builder->CreateXor(Result, ConstantInt::get(ITy, 1));
+ Result->takeName(ICI);
+ return ReplaceInstUsesWith(CI, Result);
+ }
+ }
+ }
+ }
+
+ return 0;
+}
+
+Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
+ // If one of the common conversion will work, do it.
+ if (Instruction *Result = commonIntCastTransforms(CI))
+ return Result;
+
+ Value *Src = CI.getOperand(0);
+
+ // If this is a TRUNC followed by a ZEXT then we are dealing with integral
+ // types and if the sizes are just right we can convert this into a logical
+ // 'and' which will be much cheaper than the pair of casts.
+ if (TruncInst *CSrc = dyn_cast<TruncInst>(Src)) { // A->B->C cast
+ // Get the sizes of the types involved. We know that the intermediate type
+ // will be smaller than A or C, but don't know the relation between A and C.
+ Value *A = CSrc->getOperand(0);
+ unsigned SrcSize = A->getType()->getScalarSizeInBits();
+ unsigned MidSize = CSrc->getType()->getScalarSizeInBits();
+ unsigned DstSize = CI.getType()->getScalarSizeInBits();
+ // If we're actually extending zero bits, then if
+ // SrcSize < DstSize: zext(a & mask)
+ // SrcSize == DstSize: a & mask
+ // SrcSize > DstSize: trunc(a) & mask
+ if (SrcSize < DstSize) {
+ APInt AndValue(APInt::getLowBitsSet(SrcSize, MidSize));
+ Constant *AndConst = ConstantInt::get(A->getType(), AndValue);
+ Value *And = Builder->CreateAnd(A, AndConst, CSrc->getName()+".mask");
+ return new ZExtInst(And, CI.getType());
+ }
+
+ if (SrcSize == DstSize) {
+ APInt AndValue(APInt::getLowBitsSet(SrcSize, MidSize));
+ return BinaryOperator::CreateAnd(A, ConstantInt::get(A->getType(),
+ AndValue));
+ }
+ if (SrcSize > DstSize) {
+ Value *Trunc = Builder->CreateTrunc(A, CI.getType(), "tmp");
+ APInt AndValue(APInt::getLowBitsSet(DstSize, MidSize));
+ return BinaryOperator::CreateAnd(Trunc,
+ ConstantInt::get(Trunc->getType(),
+ AndValue));
+ }
+ }
+
+ if (ICmpInst *ICI = dyn_cast<ICmpInst>(Src))
+ return transformZExtICmp(ICI, CI);
+
+ BinaryOperator *SrcI = dyn_cast<BinaryOperator>(Src);
+ if (SrcI && SrcI->getOpcode() == Instruction::Or) {
+ // zext (or icmp, icmp) --> or (zext icmp), (zext icmp) if at least one
+ // of the (zext icmp) will be transformed.
+ ICmpInst *LHS = dyn_cast<ICmpInst>(SrcI->getOperand(0));
+ ICmpInst *RHS = dyn_cast<ICmpInst>(SrcI->getOperand(1));
+ if (LHS && RHS && LHS->hasOneUse() && RHS->hasOneUse() &&
+ (transformZExtICmp(LHS, CI, false) ||
+ transformZExtICmp(RHS, CI, false))) {
+ Value *LCast = Builder->CreateZExt(LHS, CI.getType(), LHS->getName());
+ Value *RCast = Builder->CreateZExt(RHS, CI.getType(), RHS->getName());
+ return BinaryOperator::Create(Instruction::Or, LCast, RCast);
+ }
+ }
+
+ // zext(trunc(t) & C) -> (t & zext(C)).
+ if (SrcI && SrcI->getOpcode() == Instruction::And && SrcI->hasOneUse())
+ if (ConstantInt *C = dyn_cast<ConstantInt>(SrcI->getOperand(1)))
+ if (TruncInst *TI = dyn_cast<TruncInst>(SrcI->getOperand(0))) {
+ Value *TI0 = TI->getOperand(0);
+ if (TI0->getType() == CI.getType())
+ return
+ BinaryOperator::CreateAnd(TI0,
+ ConstantExpr::getZExt(C, CI.getType()));
+ }
+
+ // zext((trunc(t) & C) ^ C) -> ((t & zext(C)) ^ zext(C)).
+ if (SrcI && SrcI->getOpcode() == Instruction::Xor && SrcI->hasOneUse())
+ if (ConstantInt *C = dyn_cast<ConstantInt>(SrcI->getOperand(1)))
+ if (BinaryOperator *And = dyn_cast<BinaryOperator>(SrcI->getOperand(0)))
+ if (And->getOpcode() == Instruction::And && And->hasOneUse() &&
+ And->getOperand(1) == C)
+ if (TruncInst *TI = dyn_cast<TruncInst>(And->getOperand(0))) {
+ Value *TI0 = TI->getOperand(0);
+ if (TI0->getType() == CI.getType()) {
+ Constant *ZC = ConstantExpr::getZExt(C, CI.getType());
+ Value *NewAnd = Builder->CreateAnd(TI0, ZC, "tmp");
+ return BinaryOperator::CreateXor(NewAnd, ZC);
+ }
+ }
+
+ return 0;
+}
+
+Instruction *InstCombiner::visitSExt(SExtInst &CI) {
+ if (Instruction *I = commonIntCastTransforms(CI))
+ return I;
+
+ Value *Src = CI.getOperand(0);
+
+ // Canonicalize sign-extend from i1 to a select.
+ if (Src->getType() == Type::getInt1Ty(CI.getContext()))
+ return SelectInst::Create(Src,
+ Constant::getAllOnesValue(CI.getType()),
+ Constant::getNullValue(CI.getType()));
+
+ // See if the value being truncated is already sign extended. If so, just
+ // eliminate the trunc/sext pair.
+ if (Operator::getOpcode(Src) == Instruction::Trunc) {
+ Value *Op = cast<User>(Src)->getOperand(0);
+ unsigned OpBits = Op->getType()->getScalarSizeInBits();
+ unsigned MidBits = Src->getType()->getScalarSizeInBits();
+ unsigned DestBits = CI.getType()->getScalarSizeInBits();
+ unsigned NumSignBits = ComputeNumSignBits(Op);
+
+ if (OpBits == DestBits) {
+ // Op is i32, Mid is i8, and Dest is i32. If Op has more than 24 sign
+ // bits, it is already ready.
+ if (NumSignBits > DestBits-MidBits)
+ return ReplaceInstUsesWith(CI, Op);
+ } else if (OpBits < DestBits) {
+ // Op is i32, Mid is i8, and Dest is i64. If Op has more than 24 sign
+ // bits, just sext from i32.
+ if (NumSignBits > OpBits-MidBits)
+ return new SExtInst(Op, CI.getType(), "tmp");
+ } else {
+ // Op is i64, Mid is i8, and Dest is i32. If Op has more than 56 sign
+ // bits, just truncate to i32.
+ if (NumSignBits > OpBits-MidBits)
+ return new TruncInst(Op, CI.getType(), "tmp");
+ }
+ }
+
+ // If the input is a shl/ashr pair of a same constant, then this is a sign
+ // extension from a smaller value. If we could trust arbitrary bitwidth
+ // integers, we could turn this into a truncate to the smaller bit and then
+ // use a sext for the whole extension. Since we don't, look deeper and check
+ // for a truncate. If the source and dest are the same type, eliminate the
+ // trunc and extend and just do shifts. For example, turn:
+ // %a = trunc i32 %i to i8
+ // %b = shl i8 %a, 6
+ // %c = ashr i8 %b, 6
+ // %d = sext i8 %c to i32
+ // into:
+ // %a = shl i32 %i, 30
+ // %d = ashr i32 %a, 30
+ Value *A = 0;
+ ConstantInt *BA = 0, *CA = 0;
+ if (match(Src, m_AShr(m_Shl(m_Value(A), m_ConstantInt(BA)),
+ m_ConstantInt(CA))) &&
+ BA == CA && isa<TruncInst>(A)) {
+ Value *I = cast<TruncInst>(A)->getOperand(0);
+ if (I->getType() == CI.getType()) {
+ unsigned MidSize = Src->getType()->getScalarSizeInBits();
+ unsigned SrcDstSize = CI.getType()->getScalarSizeInBits();
+ unsigned ShAmt = CA->getZExtValue()+SrcDstSize-MidSize;
+ Constant *ShAmtV = ConstantInt::get(CI.getType(), ShAmt);
+ I = Builder->CreateShl(I, ShAmtV, CI.getName());
+ return BinaryOperator::CreateAShr(I, ShAmtV);
+ }
+ }
+
+ return 0;
+}
+
+
+/// FitsInFPType - Return a Constant* for the specified FP constant if it fits
+/// in the specified FP type without changing its value.
+static Constant *FitsInFPType(ConstantFP *CFP, const fltSemantics &Sem) {
+ bool losesInfo;
+ APFloat F = CFP->getValueAPF();
+ (void)F.convert(Sem, APFloat::rmNearestTiesToEven, &losesInfo);
+ if (!losesInfo)
+ return ConstantFP::get(CFP->getContext(), F);
+ return 0;
+}
+
+/// LookThroughFPExtensions - If this is an fp extension instruction, look
+/// through it until we get the source value.
+static Value *LookThroughFPExtensions(Value *V) {
+ if (Instruction *I = dyn_cast<Instruction>(V))
+ if (I->getOpcode() == Instruction::FPExt)
+ return LookThroughFPExtensions(I->getOperand(0));
+
+ // If this value is a constant, return the constant in the smallest FP type
+ // that can accurately represent it. This allows us to turn
+ // (float)((double)X+2.0) into x+2.0f.
+ if (ConstantFP *CFP = dyn_cast<ConstantFP>(V)) {
+ if (CFP->getType() == Type::getPPC_FP128Ty(V->getContext()))
+ return V; // No constant folding of this.
+ // See if the value can be truncated to float and then reextended.
+ if (Value *V = FitsInFPType(CFP, APFloat::IEEEsingle))
+ return V;
+ if (CFP->getType() == Type::getDoubleTy(V->getContext()))
+ return V; // Won't shrink.
+ if (Value *V = FitsInFPType(CFP, APFloat::IEEEdouble))
+ return V;
+ // Don't try to shrink to various long double types.
+ }
+
+ return V;
+}
+
+Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
+ if (Instruction *I = commonCastTransforms(CI))
+ return I;
+
+ // If we have fptrunc(fadd (fpextend x), (fpextend y)), where x and y are
+ // smaller than the destination type, we can eliminate the truncate by doing
+ // the add as the smaller type. This applies to fadd/fsub/fmul/fdiv as well
+ // as many builtins (sqrt, etc).
+ BinaryOperator *OpI = dyn_cast<BinaryOperator>(CI.getOperand(0));
+ if (OpI && OpI->hasOneUse()) {
+ switch (OpI->getOpcode()) {
+ default: break;
+ case Instruction::FAdd:
+ case Instruction::FSub:
+ case Instruction::FMul:
+ case Instruction::FDiv:
+ case Instruction::FRem:
+ const Type *SrcTy = OpI->getType();
+ Value *LHSTrunc = LookThroughFPExtensions(OpI->getOperand(0));
+ Value *RHSTrunc = LookThroughFPExtensions(OpI->getOperand(1));
+ if (LHSTrunc->getType() != SrcTy &&
+ RHSTrunc->getType() != SrcTy) {
+ unsigned DstSize = CI.getType()->getScalarSizeInBits();
+ // If the source types were both smaller than the destination type of
+ // the cast, do this xform.
+ if (LHSTrunc->getType()->getScalarSizeInBits() <= DstSize &&
+ RHSTrunc->getType()->getScalarSizeInBits() <= DstSize) {
+ LHSTrunc = Builder->CreateFPExt(LHSTrunc, CI.getType());
+ RHSTrunc = Builder->CreateFPExt(RHSTrunc, CI.getType());
+ return BinaryOperator::Create(OpI->getOpcode(), LHSTrunc, RHSTrunc);
+ }
+ }
+ break;
+ }
+ }
+ return 0;
+}
+
+Instruction *InstCombiner::visitFPExt(CastInst &CI) {
+ return commonCastTransforms(CI);
+}
+
+Instruction *InstCombiner::visitFPToUI(FPToUIInst &FI) {
+ Instruction *OpI = dyn_cast<Instruction>(FI.getOperand(0));
+ if (OpI == 0)
+ return commonCastTransforms(FI);
+
+ // fptoui(uitofp(X)) --> X
+ // fptoui(sitofp(X)) --> X
+ // This is safe if the intermediate type has enough bits in its mantissa to
+ // accurately represent all values of X. For example, do not do this with
+ // i64->float->i64. This is also safe for sitofp case, because any negative
+ // 'X' value would cause an undefined result for the fptoui.
+ if ((isa<UIToFPInst>(OpI) || isa<SIToFPInst>(OpI)) &&
+ OpI->getOperand(0)->getType() == FI.getType() &&
+ (int)FI.getType()->getScalarSizeInBits() < /*extra bit for sign */
+ OpI->getType()->getFPMantissaWidth())
+ return ReplaceInstUsesWith(FI, OpI->getOperand(0));
+
+ return commonCastTransforms(FI);
+}
+
+Instruction *InstCombiner::visitFPToSI(FPToSIInst &FI) {
+ Instruction *OpI = dyn_cast<Instruction>(FI.getOperand(0));
+ if (OpI == 0)
+ return commonCastTransforms(FI);
+
+ // fptosi(sitofp(X)) --> X
+ // fptosi(uitofp(X)) --> X
+ // This is safe if the intermediate type has enough bits in its mantissa to
+ // accurately represent all values of X. For example, do not do this with
+ // i64->float->i64. This is also safe for sitofp case, because any negative
+ // 'X' value would cause an undefined result for the fptoui.
+ if ((isa<UIToFPInst>(OpI) || isa<SIToFPInst>(OpI)) &&
+ OpI->getOperand(0)->getType() == FI.getType() &&
+ (int)FI.getType()->getScalarSizeInBits() <=
+ OpI->getType()->getFPMantissaWidth())
+ return ReplaceInstUsesWith(FI, OpI->getOperand(0));
+
+ return commonCastTransforms(FI);
+}
+
+Instruction *InstCombiner::visitUIToFP(CastInst &CI) {
+ return commonCastTransforms(CI);
+}
+
+Instruction *InstCombiner::visitSIToFP(CastInst &CI) {
+ return commonCastTransforms(CI);
+}
+
+Instruction *InstCombiner::visitPtrToInt(PtrToIntInst &CI) {
+ // If the destination integer type is smaller than the intptr_t type for
+ // this target, do a ptrtoint to intptr_t then do a trunc. This allows the
+ // trunc to be exposed to other transforms. Don't do this for extending
+ // ptrtoint's, because we don't know if the target sign or zero extends its
+ // pointers.
+ if (TD &&
+ CI.getType()->getScalarSizeInBits() < TD->getPointerSizeInBits()) {
+ Value *P = Builder->CreatePtrToInt(CI.getOperand(0),
+ TD->getIntPtrType(CI.getContext()),
+ "tmp");
+ return new TruncInst(P, CI.getType());
+ }
+
+ return commonPointerCastTransforms(CI);
+}
+
+
+Instruction *InstCombiner::visitIntToPtr(IntToPtrInst &CI) {
+ // If the source integer type is larger than the intptr_t type for
+ // this target, do a trunc to the intptr_t type, then inttoptr of it. This
+ // allows the trunc to be exposed to other transforms. Don't do this for
+ // extending inttoptr's, because we don't know if the target sign or zero
+ // extends to pointers.
+ if (TD && CI.getOperand(0)->getType()->getScalarSizeInBits() >
+ TD->getPointerSizeInBits()) {
+ Value *P = Builder->CreateTrunc(CI.getOperand(0),
+ TD->getIntPtrType(CI.getContext()), "tmp");
+ return new IntToPtrInst(P, CI.getType());
+ }
+
+ if (Instruction *I = commonCastTransforms(CI))
+ return I;
+
+ return 0;
+}
+
+Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
+ // If the operands are integer typed then apply the integer transforms,
+ // otherwise just apply the common ones.
+ Value *Src = CI.getOperand(0);
+ const Type *SrcTy = Src->getType();
+ const Type *DestTy = CI.getType();
+
+ if (isa<PointerType>(SrcTy)) {
+ if (Instruction *I = commonPointerCastTransforms(CI))
+ return I;
+ } else {
+ if (Instruction *Result = commonCastTransforms(CI))
+ return Result;
+ }
+
+
+ // Get rid of casts from one type to the same type. These are useless and can
+ // be replaced by the operand.
+ if (DestTy == Src->getType())
+ return ReplaceInstUsesWith(CI, Src);
+
+ if (const PointerType *DstPTy = dyn_cast<PointerType>(DestTy)) {
+ const PointerType *SrcPTy = cast<PointerType>(SrcTy);
+ const Type *DstElTy = DstPTy->getElementType();
+ const Type *SrcElTy = SrcPTy->getElementType();
+
+ // If the address spaces don't match, don't eliminate the bitcast, which is
+ // required for changing types.
+ if (SrcPTy->getAddressSpace() != DstPTy->getAddressSpace())
+ return 0;
+
+ // If we are casting a alloca to a pointer to a type of the same
+ // size, rewrite the allocation instruction to allocate the "right" type.
+ // There is no need to modify malloc calls because it is their bitcast that
+ // needs to be cleaned up.
+ if (AllocaInst *AI = dyn_cast<AllocaInst>(Src))
+ if (Instruction *V = PromoteCastOfAllocation(CI, *AI))
+ return V;
+
+ // If the source and destination are pointers, and this cast is equivalent
+ // to a getelementptr X, 0, 0, 0... turn it into the appropriate gep.
+ // This can enhance SROA and other transforms that want type-safe pointers.
+ Constant *ZeroUInt =
+ Constant::getNullValue(Type::getInt32Ty(CI.getContext()));
+ unsigned NumZeros = 0;
+ while (SrcElTy != DstElTy &&
+ isa<CompositeType>(SrcElTy) && !isa<PointerType>(SrcElTy) &&
+ SrcElTy->getNumContainedTypes() /* not "{}" */) {
+ SrcElTy = cast<CompositeType>(SrcElTy)->getTypeAtIndex(ZeroUInt);
+ ++NumZeros;
+ }
+
+ // If we found a path from the src to dest, create the getelementptr now.
+ if (SrcElTy == DstElTy) {
+ SmallVector<Value*, 8> Idxs(NumZeros+1, ZeroUInt);
+ return GetElementPtrInst::CreateInBounds(Src, Idxs.begin(), Idxs.end(),"",
+ ((Instruction*) NULL));
+ }
+ }
+
+ if (const VectorType *DestVTy = dyn_cast<VectorType>(DestTy)) {
+ if (DestVTy->getNumElements() == 1) {
+ if (!isa<VectorType>(SrcTy)) {
+ Value *Elem = Builder->CreateBitCast(Src, DestVTy->getElementType());
+ return InsertElementInst::Create(UndefValue::get(DestTy), Elem,
+ Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
+ }
+ // FIXME: Canonicalize bitcast(insertelement) -> insertelement(bitcast)
+ }
+ }
+
+ if (const VectorType *SrcVTy = dyn_cast<VectorType>(SrcTy)) {
+ if (SrcVTy->getNumElements() == 1) {
+ if (!isa<VectorType>(DestTy)) {
+ Value *Elem =
+ Builder->CreateExtractElement(Src,
+ Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
+ return CastInst::Create(Instruction::BitCast, Elem, DestTy);
+ }
+ }
+ }
+
+ if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(Src)) {
+ if (SVI->hasOneUse()) {
+ // Okay, we have (bitconvert (shuffle ..)). Check to see if this is
+ // a bitconvert to a vector with the same # elts.
+ if (isa<VectorType>(DestTy) &&
+ cast<VectorType>(DestTy)->getNumElements() ==
+ SVI->getType()->getNumElements() &&
+ SVI->getType()->getNumElements() ==
+ cast<VectorType>(SVI->getOperand(0)->getType())->getNumElements()) {
+ CastInst *Tmp;
+ // If either of the operands is a cast from CI.getType(), then
+ // evaluating the shuffle in the casted destination's type will allow
+ // us to eliminate at least one cast.
+ if (((Tmp = dyn_cast<CastInst>(SVI->getOperand(0))) &&
+ Tmp->getOperand(0)->getType() == DestTy) ||
+ ((Tmp = dyn_cast<CastInst>(SVI->getOperand(1))) &&
+ Tmp->getOperand(0)->getType() == DestTy)) {
+ Value *LHS = Builder->CreateBitCast(SVI->getOperand(0), DestTy);
+ Value *RHS = Builder->CreateBitCast(SVI->getOperand(1), DestTy);
+ // Return a new shuffle vector. Use the same element ID's, as we
+ // know the vector types match #elts.
+ return new ShuffleVectorInst(LHS, RHS, SVI->getOperand(2));
+ }
+ }
+ }
+ }
+ return 0;
+}
Modified: llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp?rev=92468&r1=92467&r2=92468&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp Mon Jan 4 01:53:58 2010
@@ -97,8 +97,7 @@
/// ShouldChangeType - Return true if it is desirable to convert a computation
/// from 'From' to 'To'. We don't want to convert from a legal to an illegal
/// type for example, or from a smaller to a larger illegal type.
-static bool ShouldChangeType(const Type *From, const Type *To,
- const TargetData *TD) {
+bool InstCombiner::ShouldChangeType(const Type *From, const Type *To) const {
assert(isa<IntegerType>(From) && isa<IntegerType>(To));
// If we don't have TD, we don't know if the source/dest are legal.
@@ -136,51 +135,7 @@
return 0;
}
-/// This function is a wrapper around CastInst::isEliminableCastPair. It
-/// simply extracts arguments and returns what that function returns.
-static Instruction::CastOps
-isEliminableCastPair(
- const CastInst *CI, ///< The first cast instruction
- unsigned opcode, ///< The opcode of the second cast instruction
- const Type *DstTy, ///< The target type for the second cast instruction
- TargetData *TD ///< The target data for pointer size
-) {
-
- const Type *SrcTy = CI->getOperand(0)->getType(); // A from above
- const Type *MidTy = CI->getType(); // B from above
-
- // Get the opcodes of the two Cast instructions
- Instruction::CastOps firstOp = Instruction::CastOps(CI->getOpcode());
- Instruction::CastOps secondOp = Instruction::CastOps(opcode);
-
- unsigned Res = CastInst::isEliminableCastPair(firstOp, secondOp, SrcTy, MidTy,
- DstTy,
- TD ? TD->getIntPtrType(CI->getContext()) : 0);
-
- // We don't want to form an inttoptr or ptrtoint that converts to an integer
- // type that differs from the pointer size.
- if ((Res == Instruction::IntToPtr &&
- (!TD || SrcTy != TD->getIntPtrType(CI->getContext()))) ||
- (Res == Instruction::PtrToInt &&
- (!TD || DstTy != TD->getIntPtrType(CI->getContext()))))
- Res = 0;
-
- return Instruction::CastOps(Res);
-}
-
-/// ValueRequiresCast - Return true if the cast from "V to Ty" actually results
-/// in any code being generated. It does not require codegen if V is simple
-/// enough or if the cast can be folded into other casts.
-static bool ValueRequiresCast(Instruction::CastOps opcode, const Value *V,
- const Type *Ty, TargetData *TD) {
- if (V->getType() == Ty || isa<Constant>(V)) return false;
-
- // If this is another cast that can be eliminated, it isn't codegen either.
- if (const CastInst *CI = dyn_cast<CastInst>(V))
- if (isEliminableCastPair(CI, opcode, Ty, TD))
- return false;
- return true;
-}
+
// SimplifyCommutative - This performs a few simplifications for commutative
// operators:
@@ -549,8 +504,7 @@
// constant as the other operand, try to fold the binary operator into the
// select arguments. This also works for Cast instructions, which obviously do
// not have a second operand.
-static Instruction *FoldOpIntoSelect(Instruction &Op, SelectInst *SI,
- InstCombiner *IC) {
+Instruction *InstCombiner::FoldOpIntoSelect(Instruction &Op, SelectInst *SI) {
// Don't modify shared select instructions
if (!SI->hasOneUse()) return 0;
Value *TV = SI->getOperand(1);
@@ -560,8 +514,8 @@
// Bool selects with constant operands can be folded to logical ops.
if (SI->getType() == Type::getInt1Ty(SI->getContext())) return 0;
- Value *SelectTrueVal = FoldOperationIntoSelectOperand(Op, TV, IC);
- Value *SelectFalseVal = FoldOperationIntoSelectOperand(Op, FV, IC);
+ Value *SelectTrueVal = FoldOperationIntoSelectOperand(Op, TV, this);
+ Value *SelectFalseVal = FoldOperationIntoSelectOperand(Op, FV, this);
return SelectInst::Create(SI->getCondition(), SelectTrueVal,
SelectFalseVal);
@@ -934,7 +888,7 @@
// Try to fold constant add into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(LHS))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
}
@@ -1263,7 +1217,7 @@
// Try to fold constant sub into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
// C - zext(bool) -> bool ? C - 1 : C
@@ -1453,7 +1407,7 @@
// Try to fold constant mul into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
@@ -1565,7 +1519,7 @@
// Try to fold constant mul into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
@@ -1720,7 +1674,7 @@
if (!RHS->isZero()) { // avoid X udiv 0
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
@@ -1914,7 +1868,7 @@
if (Instruction *Op0I = dyn_cast<Instruction>(Op0)) {
if (SelectInst *SI = dyn_cast<SelectInst>(Op0I)) {
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
} else if (isa<PHINode>(Op0I)) {
if (Instruction *NV = FoldOpIntoPhi(I))
@@ -2880,7 +2834,7 @@
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
@@ -2960,10 +2914,10 @@
if (SrcTy == Op1C->getOperand(0)->getType() &&
SrcTy->isIntOrIntVector() &&
// Only do this if the casts both really cause code to be generated.
- ValueRequiresCast(Op0C->getOpcode(), Op0C->getOperand(0),
- I.getType(), TD) &&
+ ValueRequiresCast(Op0C->getOpcode(), Op0C->getOperand(0),
+ I.getType()) &&
ValueRequiresCast(Op1C->getOpcode(), Op1C->getOperand(0),
- I.getType(), TD)) {
+ I.getType())) {
Value *NewOp = Builder->CreateAnd(Op0C->getOperand(0),
Op1C->getOperand(0), I.getName());
return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType());
@@ -3478,7 +3432,7 @@
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
@@ -3670,9 +3624,9 @@
// Only do this if the casts both really cause code to be
// generated.
ValueRequiresCast(Op0C->getOpcode(), Op0C->getOperand(0),
- I.getType(), TD) &&
+ I.getType()) &&
ValueRequiresCast(Op1C->getOpcode(), Op1C->getOperand(0),
- I.getType(), TD)) {
+ I.getType())) {
Value *NewOp = Builder->CreateOr(Op0C->getOperand(0),
Op1C->getOperand(0), I.getName());
return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType());
@@ -3841,7 +3795,7 @@
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
@@ -3972,9 +3926,9 @@
if (SrcTy == Op1C->getOperand(0)->getType() && SrcTy->isInteger() &&
// Only do this if the casts both really cause code to be generated.
ValueRequiresCast(Op0C->getOpcode(), Op0C->getOperand(0),
- I.getType(), TD) &&
+ I.getType()) &&
ValueRequiresCast(Op1C->getOpcode(), Op1C->getOperand(0),
- I.getType(), TD)) {
+ I.getType())) {
Value *NewOp = Builder->CreateXor(Op0C->getOperand(0),
Op1C->getOperand(0), I.getName());
return CastInst::Create(Op0C->getOpcode(), NewOp, I.getType());
@@ -4048,7 +4002,7 @@
// Try to fold constant and into select arguments.
if (isa<Constant>(Op0))
if (SelectInst *SI = dyn_cast<SelectInst>(Op1))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (ConstantInt *CUI = dyn_cast<ConstantInt>(Op1))
@@ -4086,7 +4040,7 @@
// Try to fold constant and into select arguments.
if (SelectInst *SI = dyn_cast<SelectInst>(Op0))
- if (Instruction *R = FoldOpIntoSelect(I, SI, this))
+ if (Instruction *R = FoldOpIntoSelect(I, SI))
return R;
if (isa<PHINode>(Op0))
if (Instruction *NV = FoldOpIntoPhi(I))
@@ -4755,47 +4709,14 @@
return InsertNewInstBefore(Res, *I);
}
-/// @brief Implement the transforms common to all CastInst visitors.
-Instruction *InstCombiner::commonCastTransforms(CastInst &CI) {
- Value *Src = CI.getOperand(0);
-
- // Many cases of "cast of a cast" are eliminable. If it's eliminable we just
- // eliminate it now.
- if (CastInst *CSrc = dyn_cast<CastInst>(Src)) { // A->B->C cast
- if (Instruction::CastOps opc =
- isEliminableCastPair(CSrc, CI.getOpcode(), CI.getType(), TD)) {
- // The first cast (CSrc) is eliminable so we need to fix up or replace
- // the second cast (CI). CSrc will then have a good chance of being dead.
- return CastInst::Create(opc, CSrc->getOperand(0), CI.getType());
- }
- }
- // If we are casting a select then fold the cast into the select
- if (SelectInst *SI = dyn_cast<SelectInst>(Src))
- if (Instruction *NV = FoldOpIntoSelect(CI, SI, this))
- return NV;
-
- // If we are casting a PHI then fold the cast into the PHI
- if (isa<PHINode>(Src)) {
- // We don't do this if this would create a PHI node with an illegal type if
- // it is currently legal.
- if (!isa<IntegerType>(Src->getType()) ||
- !isa<IntegerType>(CI.getType()) ||
- ShouldChangeType(CI.getType(), Src->getType(), TD))
- if (Instruction *NV = FoldOpIntoPhi(CI))
- return NV;
- }
-
- return 0;
-}
/// FindElementAtOffset - Given a type and a constant offset, determine whether
/// or not there is a sequence of GEP indices into the type that will land us at
/// the specified offset. If so, fill them into NewIndices and return the
/// resultant element type, otherwise return null.
-static const Type *FindElementAtOffset(const Type *Ty, int64_t Offset,
- SmallVectorImpl<Value*> &NewIndices,
- const TargetData *TD) {
+const Type *InstCombiner::FindElementAtOffset(const Type *Ty, int64_t Offset,
+ SmallVectorImpl<Value*> &NewIndices) {
if (!TD) return 0;
if (!Ty->isSized()) return 0;
@@ -4851,843 +4772,6 @@
return Ty;
}
-/// @brief Implement the transforms for cast of pointer (bitcast/ptrtoint)
-Instruction *InstCombiner::commonPointerCastTransforms(CastInst &CI) {
- Value *Src = CI.getOperand(0);
-
- if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Src)) {
- // If casting the result of a getelementptr instruction with no offset, turn
- // this into a cast of the original pointer!
- if (GEP->hasAllZeroIndices()) {
- // Changing the cast operand is usually not a good idea but it is safe
- // here because the pointer operand is being replaced with another
- // pointer operand so the opcode doesn't need to change.
- Worklist.Add(GEP);
- CI.setOperand(0, GEP->getOperand(0));
- return &CI;
- }
-
- // If the GEP has a single use, and the base pointer is a bitcast, and the
- // GEP computes a constant offset, see if we can convert these three
- // instructions into fewer. This typically happens with unions and other
- // non-type-safe code.
- if (TD && GEP->hasOneUse() && isa<BitCastInst>(GEP->getOperand(0))) {
- if (GEP->hasAllConstantIndices()) {
- // We are guaranteed to get a constant from EmitGEPOffset.
- ConstantInt *OffsetV = cast<ConstantInt>(EmitGEPOffset(GEP));
- int64_t Offset = OffsetV->getSExtValue();
-
- // Get the base pointer input of the bitcast, and the type it points to.
- Value *OrigBase = cast<BitCastInst>(GEP->getOperand(0))->getOperand(0);
- const Type *GEPIdxTy =
- cast<PointerType>(OrigBase->getType())->getElementType();
- SmallVector<Value*, 8> NewIndices;
- if (FindElementAtOffset(GEPIdxTy, Offset, NewIndices, TD)) {
- // If we were able to index down into an element, create the GEP
- // and bitcast the result. This eliminates one bitcast, potentially
- // two.
- Value *NGEP = cast<GEPOperator>(GEP)->isInBounds() ?
- Builder->CreateInBoundsGEP(OrigBase,
- NewIndices.begin(), NewIndices.end()) :
- Builder->CreateGEP(OrigBase, NewIndices.begin(), NewIndices.end());
- NGEP->takeName(GEP);
-
- if (isa<BitCastInst>(CI))
- return new BitCastInst(NGEP, CI.getType());
- assert(isa<PtrToIntInst>(CI));
- return new PtrToIntInst(NGEP, CI.getType());
- }
- }
- }
- }
-
- return commonCastTransforms(CI);
-}
-
-/// commonIntCastTransforms - This function implements the common transforms
-/// for trunc, zext, and sext.
-Instruction *InstCombiner::commonIntCastTransforms(CastInst &CI) {
- if (Instruction *Result = commonCastTransforms(CI))
- return Result;
-
- Value *Src = CI.getOperand(0);
- const Type *SrcTy = Src->getType();
- const Type *DestTy = CI.getType();
- uint32_t SrcBitSize = SrcTy->getScalarSizeInBits();
- uint32_t DestBitSize = DestTy->getScalarSizeInBits();
-
- // See if we can simplify any instructions used by the LHS whose sole
- // purpose is to compute bits we don't care about.
- if (SimplifyDemandedInstructionBits(CI))
- return &CI;
-
- // If the source isn't an instruction or has more than one use then we
- // can't do anything more.
- Instruction *SrcI = dyn_cast<Instruction>(Src);
- if (!SrcI || !Src->hasOneUse())
- return 0;
-
- // Attempt to propagate the cast into the instruction for int->int casts.
- int NumCastsRemoved = 0;
- // Only do this if the dest type is a simple type, don't convert the
- // expression tree to something weird like i93 unless the source is also
- // strange.
- if ((isa<VectorType>(DestTy) ||
- ShouldChangeType(SrcI->getType(), DestTy, TD)) &&
- CanEvaluateInDifferentType(SrcI, DestTy,
- CI.getOpcode(), NumCastsRemoved)) {
- // If this cast is a truncate, evaluting in a different type always
- // eliminates the cast, so it is always a win. If this is a zero-extension,
- // we need to do an AND to maintain the clear top-part of the computation,
- // so we require that the input have eliminated at least one cast. If this
- // is a sign extension, we insert two new casts (to do the extension) so we
- // require that two casts have been eliminated.
- bool DoXForm = false;
- bool JustReplace = false;
- switch (CI.getOpcode()) {
- default:
- // All the others use floating point so we shouldn't actually
- // get here because of the check above.
- llvm_unreachable("Unknown cast type");
- case Instruction::Trunc:
- DoXForm = true;
- break;
- case Instruction::ZExt: {
- DoXForm = NumCastsRemoved >= 1;
-
- if (!DoXForm && 0) {
- // If it's unnecessary to issue an AND to clear the high bits, it's
- // always profitable to do this xform.
- Value *TryRes = EvaluateInDifferentType(SrcI, DestTy, false);
- APInt Mask(APInt::getBitsSet(DestBitSize, SrcBitSize, DestBitSize));
- if (MaskedValueIsZero(TryRes, Mask))
- return ReplaceInstUsesWith(CI, TryRes);
-
- if (Instruction *TryI = dyn_cast<Instruction>(TryRes))
- if (TryI->use_empty())
- EraseInstFromFunction(*TryI);
- }
- break;
- }
- case Instruction::SExt: {
- DoXForm = NumCastsRemoved >= 2;
- if (!DoXForm && !isa<TruncInst>(SrcI) && 0) {
- // If we do not have to emit the truncate + sext pair, then it's always
- // profitable to do this xform.
- //
- // It's not safe to eliminate the trunc + sext pair if one of the
- // eliminated cast is a truncate. e.g.
- // t2 = trunc i32 t1 to i16
- // t3 = sext i16 t2 to i32
- // !=
- // i32 t1
- Value *TryRes = EvaluateInDifferentType(SrcI, DestTy, true);
- unsigned NumSignBits = ComputeNumSignBits(TryRes);
- if (NumSignBits > (DestBitSize - SrcBitSize))
- return ReplaceInstUsesWith(CI, TryRes);
-
- if (Instruction *TryI = dyn_cast<Instruction>(TryRes))
- if (TryI->use_empty())
- EraseInstFromFunction(*TryI);
- }
- break;
- }
- }
-
- if (DoXForm) {
- DEBUG(errs() << "ICE: EvaluateInDifferentType converting expression type"
- " to avoid cast: " << CI);
- Value *Res = EvaluateInDifferentType(SrcI, DestTy,
- CI.getOpcode() == Instruction::SExt);
- if (JustReplace)
- // Just replace this cast with the result.
- return ReplaceInstUsesWith(CI, Res);
-
- assert(Res->getType() == DestTy);
- switch (CI.getOpcode()) {
- default: llvm_unreachable("Unknown cast type!");
- case Instruction::Trunc:
- // Just replace this cast with the result.
- return ReplaceInstUsesWith(CI, Res);
- case Instruction::ZExt: {
- assert(SrcBitSize < DestBitSize && "Not a zext?");
-
- // If the high bits are already zero, just replace this cast with the
- // result.
- APInt Mask(APInt::getBitsSet(DestBitSize, SrcBitSize, DestBitSize));
- if (MaskedValueIsZero(Res, Mask))
- return ReplaceInstUsesWith(CI, Res);
-
- // We need to emit an AND to clear the high bits.
- Constant *C = ConstantInt::get(CI.getContext(),
- APInt::getLowBitsSet(DestBitSize, SrcBitSize));
- return BinaryOperator::CreateAnd(Res, C);
- }
- case Instruction::SExt: {
- // If the high bits are already filled with sign bit, just replace this
- // cast with the result.
- unsigned NumSignBits = ComputeNumSignBits(Res);
- if (NumSignBits > (DestBitSize - SrcBitSize))
- return ReplaceInstUsesWith(CI, Res);
-
- // We need to emit a cast to truncate, then a cast to sext.
- return new SExtInst(Builder->CreateTrunc(Res, Src->getType()), DestTy);
- }
- }
- }
- }
-
- Value *Op0 = SrcI->getNumOperands() > 0 ? SrcI->getOperand(0) : 0;
- Value *Op1 = SrcI->getNumOperands() > 1 ? SrcI->getOperand(1) : 0;
-
- switch (SrcI->getOpcode()) {
- case Instruction::Add:
- case Instruction::Mul:
- case Instruction::And:
- case Instruction::Or:
- case Instruction::Xor:
- // If we are discarding information, rewrite.
- if (DestBitSize < SrcBitSize && DestBitSize != 1) {
- // Don't insert two casts unless at least one can be eliminated.
- if (!ValueRequiresCast(CI.getOpcode(), Op1, DestTy, TD) ||
- !ValueRequiresCast(CI.getOpcode(), Op0, DestTy, TD)) {
- Value *Op0c = Builder->CreateTrunc(Op0, DestTy, Op0->getName());
- Value *Op1c = Builder->CreateTrunc(Op1, DestTy, Op1->getName());
- return BinaryOperator::Create(
- cast<BinaryOperator>(SrcI)->getOpcode(), Op0c, Op1c);
- }
- }
-
- // cast (xor bool X, true) to int --> xor (cast bool X to int), 1
- if (isa<ZExtInst>(CI) && SrcBitSize == 1 &&
- SrcI->getOpcode() == Instruction::Xor &&
- Op1 == ConstantInt::getTrue(CI.getContext()) &&
- (!Op0->hasOneUse() || !isa<CmpInst>(Op0))) {
- Value *New = Builder->CreateZExt(Op0, DestTy, Op0->getName());
- return BinaryOperator::CreateXor(New,
- ConstantInt::get(CI.getType(), 1));
- }
- break;
-
- case Instruction::Shl: {
- // Canonicalize trunc inside shl, if we can.
- ConstantInt *CI = dyn_cast<ConstantInt>(Op1);
- if (CI && DestBitSize < SrcBitSize &&
- CI->getLimitedValue(DestBitSize) < DestBitSize) {
- Value *Op0c = Builder->CreateTrunc(Op0, DestTy, Op0->getName());
- Value *Op1c = Builder->CreateTrunc(Op1, DestTy, Op1->getName());
- return BinaryOperator::CreateShl(Op0c, Op1c);
- }
- break;
- }
- }
- return 0;
-}
-
-Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
- if (Instruction *Result = commonIntCastTransforms(CI))
- return Result;
-
- Value *Src = CI.getOperand(0);
- const Type *Ty = CI.getType();
- uint32_t DestBitWidth = Ty->getScalarSizeInBits();
- uint32_t SrcBitWidth = Src->getType()->getScalarSizeInBits();
-
- // Canonicalize trunc x to i1 -> (icmp ne (and x, 1), 0)
- if (DestBitWidth == 1) {
- Constant *One = ConstantInt::get(Src->getType(), 1);
- Src = Builder->CreateAnd(Src, One, "tmp");
- Value *Zero = Constant::getNullValue(Src->getType());
- return new ICmpInst(ICmpInst::ICMP_NE, Src, Zero);
- }
-
- // Optimize trunc(lshr(), c) to pull the shift through the truncate.
- ConstantInt *ShAmtV = 0;
- Value *ShiftOp = 0;
- if (Src->hasOneUse() &&
- match(Src, m_LShr(m_Value(ShiftOp), m_ConstantInt(ShAmtV)))) {
- uint32_t ShAmt = ShAmtV->getLimitedValue(SrcBitWidth);
-
- // Get a mask for the bits shifting in.
- APInt Mask(APInt::getLowBitsSet(SrcBitWidth, ShAmt).shl(DestBitWidth));
- if (MaskedValueIsZero(ShiftOp, Mask)) {
- if (ShAmt >= DestBitWidth) // All zeros.
- return ReplaceInstUsesWith(CI, Constant::getNullValue(Ty));
-
- // Okay, we can shrink this. Truncate the input, then return a new
- // shift.
- Value *V1 = Builder->CreateTrunc(ShiftOp, Ty, ShiftOp->getName());
- Value *V2 = ConstantExpr::getTrunc(ShAmtV, Ty);
- return BinaryOperator::CreateLShr(V1, V2);
- }
- }
-
- return 0;
-}
-
-/// transformZExtICmp - Transform (zext icmp) to bitwise / integer operations
-/// in order to eliminate the icmp.
-Instruction *InstCombiner::transformZExtICmp(ICmpInst *ICI, Instruction &CI,
- bool DoXform) {
- // If we are just checking for a icmp eq of a single bit and zext'ing it
- // to an integer, then shift the bit to the appropriate place and then
- // cast to integer to avoid the comparison.
- if (ConstantInt *Op1C = dyn_cast<ConstantInt>(ICI->getOperand(1))) {
- const APInt &Op1CV = Op1C->getValue();
-
- // zext (x <s 0) to i32 --> x>>u31 true if signbit set.
- // zext (x >s -1) to i32 --> (x>>u31)^1 true if signbit clear.
- if ((ICI->getPredicate() == ICmpInst::ICMP_SLT && Op1CV == 0) ||
- (ICI->getPredicate() == ICmpInst::ICMP_SGT &&Op1CV.isAllOnesValue())) {
- if (!DoXform) return ICI;
-
- Value *In = ICI->getOperand(0);
- Value *Sh = ConstantInt::get(In->getType(),
- In->getType()->getScalarSizeInBits()-1);
- In = Builder->CreateLShr(In, Sh, In->getName()+".lobit");
- if (In->getType() != CI.getType())
- In = Builder->CreateIntCast(In, CI.getType(), false/*ZExt*/, "tmp");
-
- if (ICI->getPredicate() == ICmpInst::ICMP_SGT) {
- Constant *One = ConstantInt::get(In->getType(), 1);
- In = Builder->CreateXor(In, One, In->getName()+".not");
- }
-
- return ReplaceInstUsesWith(CI, In);
- }
-
-
-
- // zext (X == 0) to i32 --> X^1 iff X has only the low bit set.
- // zext (X == 0) to i32 --> (X>>1)^1 iff X has only the 2nd bit set.
- // zext (X == 1) to i32 --> X iff X has only the low bit set.
- // zext (X == 2) to i32 --> X>>1 iff X has only the 2nd bit set.
- // zext (X != 0) to i32 --> X iff X has only the low bit set.
- // zext (X != 0) to i32 --> X>>1 iff X has only the 2nd bit set.
- // zext (X != 1) to i32 --> X^1 iff X has only the low bit set.
- // zext (X != 2) to i32 --> (X>>1)^1 iff X has only the 2nd bit set.
- if ((Op1CV == 0 || Op1CV.isPowerOf2()) &&
- // This only works for EQ and NE
- ICI->isEquality()) {
- // If Op1C some other power of two, convert:
- uint32_t BitWidth = Op1C->getType()->getBitWidth();
- APInt KnownZero(BitWidth, 0), KnownOne(BitWidth, 0);
- APInt TypeMask(APInt::getAllOnesValue(BitWidth));
- ComputeMaskedBits(ICI->getOperand(0), TypeMask, KnownZero, KnownOne);
-
- APInt KnownZeroMask(~KnownZero);
- if (KnownZeroMask.isPowerOf2()) { // Exactly 1 possible 1?
- if (!DoXform) return ICI;
-
- bool isNE = ICI->getPredicate() == ICmpInst::ICMP_NE;
- if (Op1CV != 0 && (Op1CV != KnownZeroMask)) {
- // (X&4) == 2 --> false
- // (X&4) != 2 --> true
- Constant *Res = ConstantInt::get(Type::getInt1Ty(CI.getContext()),
- isNE);
- Res = ConstantExpr::getZExt(Res, CI.getType());
- return ReplaceInstUsesWith(CI, Res);
- }
-
- uint32_t ShiftAmt = KnownZeroMask.logBase2();
- Value *In = ICI->getOperand(0);
- if (ShiftAmt) {
- // Perform a logical shr by shiftamt.
- // Insert the shift to put the result in the low bit.
- In = Builder->CreateLShr(In, ConstantInt::get(In->getType(),ShiftAmt),
- In->getName()+".lobit");
- }
-
- if ((Op1CV != 0) == isNE) { // Toggle the low bit.
- Constant *One = ConstantInt::get(In->getType(), 1);
- In = Builder->CreateXor(In, One, "tmp");
- }
-
- if (CI.getType() == In->getType())
- return ReplaceInstUsesWith(CI, In);
- else
- return CastInst::CreateIntegerCast(In, CI.getType(), false/*ZExt*/);
- }
- }
- }
-
- // icmp ne A, B is equal to xor A, B when A and B only really have one bit.
- // It is also profitable to transform icmp eq into not(xor(A, B)) because that
- // may lead to additional simplifications.
- if (ICI->isEquality() && CI.getType() == ICI->getOperand(0)->getType()) {
- if (const IntegerType *ITy = dyn_cast<IntegerType>(CI.getType())) {
- uint32_t BitWidth = ITy->getBitWidth();
- Value *LHS = ICI->getOperand(0);
- Value *RHS = ICI->getOperand(1);
-
- APInt KnownZeroLHS(BitWidth, 0), KnownOneLHS(BitWidth, 0);
- APInt KnownZeroRHS(BitWidth, 0), KnownOneRHS(BitWidth, 0);
- APInt TypeMask(APInt::getAllOnesValue(BitWidth));
- ComputeMaskedBits(LHS, TypeMask, KnownZeroLHS, KnownOneLHS);
- ComputeMaskedBits(RHS, TypeMask, KnownZeroRHS, KnownOneRHS);
-
- if (KnownZeroLHS == KnownZeroRHS && KnownOneLHS == KnownOneRHS) {
- APInt KnownBits = KnownZeroLHS | KnownOneLHS;
- APInt UnknownBit = ~KnownBits;
- if (UnknownBit.countPopulation() == 1) {
- if (!DoXform) return ICI;
-
- Value *Result = Builder->CreateXor(LHS, RHS);
-
- // Mask off any bits that are set and won't be shifted away.
- if (KnownOneLHS.uge(UnknownBit))
- Result = Builder->CreateAnd(Result,
- ConstantInt::get(ITy, UnknownBit));
-
- // Shift the bit we're testing down to the lsb.
- Result = Builder->CreateLShr(
- Result, ConstantInt::get(ITy, UnknownBit.countTrailingZeros()));
-
- if (ICI->getPredicate() == ICmpInst::ICMP_EQ)
- Result = Builder->CreateXor(Result, ConstantInt::get(ITy, 1));
- Result->takeName(ICI);
- return ReplaceInstUsesWith(CI, Result);
- }
- }
- }
- }
-
- return 0;
-}
-
-Instruction *InstCombiner::visitZExt(ZExtInst &CI) {
- // If one of the common conversion will work, do it.
- if (Instruction *Result = commonIntCastTransforms(CI))
- return Result;
-
- Value *Src = CI.getOperand(0);
-
- // If this is a TRUNC followed by a ZEXT then we are dealing with integral
- // types and if the sizes are just right we can convert this into a logical
- // 'and' which will be much cheaper than the pair of casts.
- if (TruncInst *CSrc = dyn_cast<TruncInst>(Src)) { // A->B->C cast
- // Get the sizes of the types involved. We know that the intermediate type
- // will be smaller than A or C, but don't know the relation between A and C.
- Value *A = CSrc->getOperand(0);
- unsigned SrcSize = A->getType()->getScalarSizeInBits();
- unsigned MidSize = CSrc->getType()->getScalarSizeInBits();
- unsigned DstSize = CI.getType()->getScalarSizeInBits();
- // If we're actually extending zero bits, then if
- // SrcSize < DstSize: zext(a & mask)
- // SrcSize == DstSize: a & mask
- // SrcSize > DstSize: trunc(a) & mask
- if (SrcSize < DstSize) {
- APInt AndValue(APInt::getLowBitsSet(SrcSize, MidSize));
- Constant *AndConst = ConstantInt::get(A->getType(), AndValue);
- Value *And = Builder->CreateAnd(A, AndConst, CSrc->getName()+".mask");
- return new ZExtInst(And, CI.getType());
- }
-
- if (SrcSize == DstSize) {
- APInt AndValue(APInt::getLowBitsSet(SrcSize, MidSize));
- return BinaryOperator::CreateAnd(A, ConstantInt::get(A->getType(),
- AndValue));
- }
- if (SrcSize > DstSize) {
- Value *Trunc = Builder->CreateTrunc(A, CI.getType(), "tmp");
- APInt AndValue(APInt::getLowBitsSet(DstSize, MidSize));
- return BinaryOperator::CreateAnd(Trunc,
- ConstantInt::get(Trunc->getType(),
- AndValue));
- }
- }
-
- if (ICmpInst *ICI = dyn_cast<ICmpInst>(Src))
- return transformZExtICmp(ICI, CI);
-
- BinaryOperator *SrcI = dyn_cast<BinaryOperator>(Src);
- if (SrcI && SrcI->getOpcode() == Instruction::Or) {
- // zext (or icmp, icmp) --> or (zext icmp), (zext icmp) if at least one
- // of the (zext icmp) will be transformed.
- ICmpInst *LHS = dyn_cast<ICmpInst>(SrcI->getOperand(0));
- ICmpInst *RHS = dyn_cast<ICmpInst>(SrcI->getOperand(1));
- if (LHS && RHS && LHS->hasOneUse() && RHS->hasOneUse() &&
- (transformZExtICmp(LHS, CI, false) ||
- transformZExtICmp(RHS, CI, false))) {
- Value *LCast = Builder->CreateZExt(LHS, CI.getType(), LHS->getName());
- Value *RCast = Builder->CreateZExt(RHS, CI.getType(), RHS->getName());
- return BinaryOperator::Create(Instruction::Or, LCast, RCast);
- }
- }
-
- // zext(trunc(t) & C) -> (t & zext(C)).
- if (SrcI && SrcI->getOpcode() == Instruction::And && SrcI->hasOneUse())
- if (ConstantInt *C = dyn_cast<ConstantInt>(SrcI->getOperand(1)))
- if (TruncInst *TI = dyn_cast<TruncInst>(SrcI->getOperand(0))) {
- Value *TI0 = TI->getOperand(0);
- if (TI0->getType() == CI.getType())
- return
- BinaryOperator::CreateAnd(TI0,
- ConstantExpr::getZExt(C, CI.getType()));
- }
-
- // zext((trunc(t) & C) ^ C) -> ((t & zext(C)) ^ zext(C)).
- if (SrcI && SrcI->getOpcode() == Instruction::Xor && SrcI->hasOneUse())
- if (ConstantInt *C = dyn_cast<ConstantInt>(SrcI->getOperand(1)))
- if (BinaryOperator *And = dyn_cast<BinaryOperator>(SrcI->getOperand(0)))
- if (And->getOpcode() == Instruction::And && And->hasOneUse() &&
- And->getOperand(1) == C)
- if (TruncInst *TI = dyn_cast<TruncInst>(And->getOperand(0))) {
- Value *TI0 = TI->getOperand(0);
- if (TI0->getType() == CI.getType()) {
- Constant *ZC = ConstantExpr::getZExt(C, CI.getType());
- Value *NewAnd = Builder->CreateAnd(TI0, ZC, "tmp");
- return BinaryOperator::CreateXor(NewAnd, ZC);
- }
- }
-
- return 0;
-}
-
-Instruction *InstCombiner::visitSExt(SExtInst &CI) {
- if (Instruction *I = commonIntCastTransforms(CI))
- return I;
-
- Value *Src = CI.getOperand(0);
-
- // Canonicalize sign-extend from i1 to a select.
- if (Src->getType() == Type::getInt1Ty(CI.getContext()))
- return SelectInst::Create(Src,
- Constant::getAllOnesValue(CI.getType()),
- Constant::getNullValue(CI.getType()));
-
- // See if the value being truncated is already sign extended. If so, just
- // eliminate the trunc/sext pair.
- if (Operator::getOpcode(Src) == Instruction::Trunc) {
- Value *Op = cast<User>(Src)->getOperand(0);
- unsigned OpBits = Op->getType()->getScalarSizeInBits();
- unsigned MidBits = Src->getType()->getScalarSizeInBits();
- unsigned DestBits = CI.getType()->getScalarSizeInBits();
- unsigned NumSignBits = ComputeNumSignBits(Op);
-
- if (OpBits == DestBits) {
- // Op is i32, Mid is i8, and Dest is i32. If Op has more than 24 sign
- // bits, it is already ready.
- if (NumSignBits > DestBits-MidBits)
- return ReplaceInstUsesWith(CI, Op);
- } else if (OpBits < DestBits) {
- // Op is i32, Mid is i8, and Dest is i64. If Op has more than 24 sign
- // bits, just sext from i32.
- if (NumSignBits > OpBits-MidBits)
- return new SExtInst(Op, CI.getType(), "tmp");
- } else {
- // Op is i64, Mid is i8, and Dest is i32. If Op has more than 56 sign
- // bits, just truncate to i32.
- if (NumSignBits > OpBits-MidBits)
- return new TruncInst(Op, CI.getType(), "tmp");
- }
- }
-
- // If the input is a shl/ashr pair of a same constant, then this is a sign
- // extension from a smaller value. If we could trust arbitrary bitwidth
- // integers, we could turn this into a truncate to the smaller bit and then
- // use a sext for the whole extension. Since we don't, look deeper and check
- // for a truncate. If the source and dest are the same type, eliminate the
- // trunc and extend and just do shifts. For example, turn:
- // %a = trunc i32 %i to i8
- // %b = shl i8 %a, 6
- // %c = ashr i8 %b, 6
- // %d = sext i8 %c to i32
- // into:
- // %a = shl i32 %i, 30
- // %d = ashr i32 %a, 30
- Value *A = 0;
- ConstantInt *BA = 0, *CA = 0;
- if (match(Src, m_AShr(m_Shl(m_Value(A), m_ConstantInt(BA)),
- m_ConstantInt(CA))) &&
- BA == CA && isa<TruncInst>(A)) {
- Value *I = cast<TruncInst>(A)->getOperand(0);
- if (I->getType() == CI.getType()) {
- unsigned MidSize = Src->getType()->getScalarSizeInBits();
- unsigned SrcDstSize = CI.getType()->getScalarSizeInBits();
- unsigned ShAmt = CA->getZExtValue()+SrcDstSize-MidSize;
- Constant *ShAmtV = ConstantInt::get(CI.getType(), ShAmt);
- I = Builder->CreateShl(I, ShAmtV, CI.getName());
- return BinaryOperator::CreateAShr(I, ShAmtV);
- }
- }
-
- return 0;
-}
-
-/// FitsInFPType - Return a Constant* for the specified FP constant if it fits
-/// in the specified FP type without changing its value.
-static Constant *FitsInFPType(ConstantFP *CFP, const fltSemantics &Sem) {
- bool losesInfo;
- APFloat F = CFP->getValueAPF();
- (void)F.convert(Sem, APFloat::rmNearestTiesToEven, &losesInfo);
- if (!losesInfo)
- return ConstantFP::get(CFP->getContext(), F);
- return 0;
-}
-
-/// LookThroughFPExtensions - If this is an fp extension instruction, look
-/// through it until we get the source value.
-static Value *LookThroughFPExtensions(Value *V) {
- if (Instruction *I = dyn_cast<Instruction>(V))
- if (I->getOpcode() == Instruction::FPExt)
- return LookThroughFPExtensions(I->getOperand(0));
-
- // If this value is a constant, return the constant in the smallest FP type
- // that can accurately represent it. This allows us to turn
- // (float)((double)X+2.0) into x+2.0f.
- if (ConstantFP *CFP = dyn_cast<ConstantFP>(V)) {
- if (CFP->getType() == Type::getPPC_FP128Ty(V->getContext()))
- return V; // No constant folding of this.
- // See if the value can be truncated to float and then reextended.
- if (Value *V = FitsInFPType(CFP, APFloat::IEEEsingle))
- return V;
- if (CFP->getType() == Type::getDoubleTy(V->getContext()))
- return V; // Won't shrink.
- if (Value *V = FitsInFPType(CFP, APFloat::IEEEdouble))
- return V;
- // Don't try to shrink to various long double types.
- }
-
- return V;
-}
-
-Instruction *InstCombiner::visitFPTrunc(FPTruncInst &CI) {
- if (Instruction *I = commonCastTransforms(CI))
- return I;
-
- // If we have fptrunc(fadd (fpextend x), (fpextend y)), where x and y are
- // smaller than the destination type, we can eliminate the truncate by doing
- // the add as the smaller type. This applies to fadd/fsub/fmul/fdiv as well as
- // many builtins (sqrt, etc).
- BinaryOperator *OpI = dyn_cast<BinaryOperator>(CI.getOperand(0));
- if (OpI && OpI->hasOneUse()) {
- switch (OpI->getOpcode()) {
- default: break;
- case Instruction::FAdd:
- case Instruction::FSub:
- case Instruction::FMul:
- case Instruction::FDiv:
- case Instruction::FRem:
- const Type *SrcTy = OpI->getType();
- Value *LHSTrunc = LookThroughFPExtensions(OpI->getOperand(0));
- Value *RHSTrunc = LookThroughFPExtensions(OpI->getOperand(1));
- if (LHSTrunc->getType() != SrcTy &&
- RHSTrunc->getType() != SrcTy) {
- unsigned DstSize = CI.getType()->getScalarSizeInBits();
- // If the source types were both smaller than the destination type of
- // the cast, do this xform.
- if (LHSTrunc->getType()->getScalarSizeInBits() <= DstSize &&
- RHSTrunc->getType()->getScalarSizeInBits() <= DstSize) {
- LHSTrunc = Builder->CreateFPExt(LHSTrunc, CI.getType());
- RHSTrunc = Builder->CreateFPExt(RHSTrunc, CI.getType());
- return BinaryOperator::Create(OpI->getOpcode(), LHSTrunc, RHSTrunc);
- }
- }
- break;
- }
- }
- return 0;
-}
-
-Instruction *InstCombiner::visitFPExt(CastInst &CI) {
- return commonCastTransforms(CI);
-}
-
-Instruction *InstCombiner::visitFPToUI(FPToUIInst &FI) {
- Instruction *OpI = dyn_cast<Instruction>(FI.getOperand(0));
- if (OpI == 0)
- return commonCastTransforms(FI);
-
- // fptoui(uitofp(X)) --> X
- // fptoui(sitofp(X)) --> X
- // This is safe if the intermediate type has enough bits in its mantissa to
- // accurately represent all values of X. For example, do not do this with
- // i64->float->i64. This is also safe for sitofp case, because any negative
- // 'X' value would cause an undefined result for the fptoui.
- if ((isa<UIToFPInst>(OpI) || isa<SIToFPInst>(OpI)) &&
- OpI->getOperand(0)->getType() == FI.getType() &&
- (int)FI.getType()->getScalarSizeInBits() < /*extra bit for sign */
- OpI->getType()->getFPMantissaWidth())
- return ReplaceInstUsesWith(FI, OpI->getOperand(0));
-
- return commonCastTransforms(FI);
-}
-
-Instruction *InstCombiner::visitFPToSI(FPToSIInst &FI) {
- Instruction *OpI = dyn_cast<Instruction>(FI.getOperand(0));
- if (OpI == 0)
- return commonCastTransforms(FI);
-
- // fptosi(sitofp(X)) --> X
- // fptosi(uitofp(X)) --> X
- // This is safe if the intermediate type has enough bits in its mantissa to
- // accurately represent all values of X. For example, do not do this with
- // i64->float->i64. This is also safe for sitofp case, because any negative
- // 'X' value would cause an undefined result for the fptoui.
- if ((isa<UIToFPInst>(OpI) || isa<SIToFPInst>(OpI)) &&
- OpI->getOperand(0)->getType() == FI.getType() &&
- (int)FI.getType()->getScalarSizeInBits() <=
- OpI->getType()->getFPMantissaWidth())
- return ReplaceInstUsesWith(FI, OpI->getOperand(0));
-
- return commonCastTransforms(FI);
-}
-
-Instruction *InstCombiner::visitUIToFP(CastInst &CI) {
- return commonCastTransforms(CI);
-}
-
-Instruction *InstCombiner::visitSIToFP(CastInst &CI) {
- return commonCastTransforms(CI);
-}
-
-Instruction *InstCombiner::visitPtrToInt(PtrToIntInst &CI) {
- // If the destination integer type is smaller than the intptr_t type for
- // this target, do a ptrtoint to intptr_t then do a trunc. This allows the
- // trunc to be exposed to other transforms. Don't do this for extending
- // ptrtoint's, because we don't know if the target sign or zero extends its
- // pointers.
- if (TD &&
- CI.getType()->getScalarSizeInBits() < TD->getPointerSizeInBits()) {
- Value *P = Builder->CreatePtrToInt(CI.getOperand(0),
- TD->getIntPtrType(CI.getContext()),
- "tmp");
- return new TruncInst(P, CI.getType());
- }
-
- return commonPointerCastTransforms(CI);
-}
-
-Instruction *InstCombiner::visitIntToPtr(IntToPtrInst &CI) {
- // If the source integer type is larger than the intptr_t type for
- // this target, do a trunc to the intptr_t type, then inttoptr of it. This
- // allows the trunc to be exposed to other transforms. Don't do this for
- // extending inttoptr's, because we don't know if the target sign or zero
- // extends to pointers.
- if (TD && CI.getOperand(0)->getType()->getScalarSizeInBits() >
- TD->getPointerSizeInBits()) {
- Value *P = Builder->CreateTrunc(CI.getOperand(0),
- TD->getIntPtrType(CI.getContext()), "tmp");
- return new IntToPtrInst(P, CI.getType());
- }
-
- if (Instruction *I = commonCastTransforms(CI))
- return I;
-
- return 0;
-}
-
-Instruction *InstCombiner::visitBitCast(BitCastInst &CI) {
- // If the operands are integer typed then apply the integer transforms,
- // otherwise just apply the common ones.
- Value *Src = CI.getOperand(0);
- const Type *SrcTy = Src->getType();
- const Type *DestTy = CI.getType();
-
- if (isa<PointerType>(SrcTy)) {
- if (Instruction *I = commonPointerCastTransforms(CI))
- return I;
- } else {
- if (Instruction *Result = commonCastTransforms(CI))
- return Result;
- }
-
-
- // Get rid of casts from one type to the same type. These are useless and can
- // be replaced by the operand.
- if (DestTy == Src->getType())
- return ReplaceInstUsesWith(CI, Src);
-
- if (const PointerType *DstPTy = dyn_cast<PointerType>(DestTy)) {
- const PointerType *SrcPTy = cast<PointerType>(SrcTy);
- const Type *DstElTy = DstPTy->getElementType();
- const Type *SrcElTy = SrcPTy->getElementType();
-
- // If the address spaces don't match, don't eliminate the bitcast, which is
- // required for changing types.
- if (SrcPTy->getAddressSpace() != DstPTy->getAddressSpace())
- return 0;
-
- // If we are casting a alloca to a pointer to a type of the same
- // size, rewrite the allocation instruction to allocate the "right" type.
- // There is no need to modify malloc calls because it is their bitcast that
- // needs to be cleaned up.
- if (AllocaInst *AI = dyn_cast<AllocaInst>(Src))
- if (Instruction *V = PromoteCastOfAllocation(CI, *AI))
- return V;
-
- // If the source and destination are pointers, and this cast is equivalent
- // to a getelementptr X, 0, 0, 0... turn it into the appropriate gep.
- // This can enhance SROA and other transforms that want type-safe pointers.
- Constant *ZeroUInt =
- Constant::getNullValue(Type::getInt32Ty(CI.getContext()));
- unsigned NumZeros = 0;
- while (SrcElTy != DstElTy &&
- isa<CompositeType>(SrcElTy) && !isa<PointerType>(SrcElTy) &&
- SrcElTy->getNumContainedTypes() /* not "{}" */) {
- SrcElTy = cast<CompositeType>(SrcElTy)->getTypeAtIndex(ZeroUInt);
- ++NumZeros;
- }
-
- // If we found a path from the src to dest, create the getelementptr now.
- if (SrcElTy == DstElTy) {
- SmallVector<Value*, 8> Idxs(NumZeros+1, ZeroUInt);
- return GetElementPtrInst::CreateInBounds(Src, Idxs.begin(), Idxs.end(),"",
- ((Instruction*) NULL));
- }
- }
-
- if (const VectorType *DestVTy = dyn_cast<VectorType>(DestTy)) {
- if (DestVTy->getNumElements() == 1) {
- if (!isa<VectorType>(SrcTy)) {
- Value *Elem = Builder->CreateBitCast(Src, DestVTy->getElementType());
- return InsertElementInst::Create(UndefValue::get(DestTy), Elem,
- Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
- }
- // FIXME: Canonicalize bitcast(insertelement) -> insertelement(bitcast)
- }
- }
-
- if (const VectorType *SrcVTy = dyn_cast<VectorType>(SrcTy)) {
- if (SrcVTy->getNumElements() == 1) {
- if (!isa<VectorType>(DestTy)) {
- Value *Elem =
- Builder->CreateExtractElement(Src,
- Constant::getNullValue(Type::getInt32Ty(CI.getContext())));
- return CastInst::Create(Instruction::BitCast, Elem, DestTy);
- }
- }
- }
-
- if (ShuffleVectorInst *SVI = dyn_cast<ShuffleVectorInst>(Src)) {
- if (SVI->hasOneUse()) {
- // Okay, we have (bitconvert (shuffle ..)). Check to see if this is
- // a bitconvert to a vector with the same # elts.
- if (isa<VectorType>(DestTy) &&
- cast<VectorType>(DestTy)->getNumElements() ==
- SVI->getType()->getNumElements() &&
- SVI->getType()->getNumElements() ==
- cast<VectorType>(SVI->getOperand(0)->getType())->getNumElements()) {
- CastInst *Tmp;
- // If either of the operands is a cast from CI.getType(), then
- // evaluating the shuffle in the casted destination's type will allow
- // us to eliminate at least one cast.
- if (((Tmp = dyn_cast<CastInst>(SVI->getOperand(0))) &&
- Tmp->getOperand(0)->getType() == DestTy) ||
- ((Tmp = dyn_cast<CastInst>(SVI->getOperand(1))) &&
- Tmp->getOperand(0)->getType() == DestTy)) {
- Value *LHS = Builder->CreateBitCast(SVI->getOperand(0), DestTy);
- Value *RHS = Builder->CreateBitCast(SVI->getOperand(1), DestTy);
- // Return a new shuffle vector. Use the same element ID's, as we
- // know the vector types match #elts.
- return new ShuffleVectorInst(LHS, RHS, SVI->getOperand(2));
- }
- }
- }
- }
- return 0;
-}
/// GetSelectFoldableOperands - We want to turn code that looks like this:
/// %C = or %A, %B
@@ -7741,7 +6825,7 @@
// Be careful about transforming integer PHIs. We don't want to pessimize
// the code by turning an i32 into an i1293.
if (isa<IntegerType>(PN.getType()) && isa<IntegerType>(CastSrcTy)) {
- if (!ShouldChangeType(PN.getType(), CastSrcTy, TD))
+ if (!ShouldChangeType(PN.getType(), CastSrcTy))
return 0;
}
} else if (isa<BinaryOperator>(FirstInst) || isa<CmpInst>(FirstInst)) {
@@ -8485,7 +7569,7 @@
SmallVector<Value*, 8> NewIndices;
const Type *InTy =
cast<PointerType>(BCI->getOperand(0)->getType())->getElementType();
- if (FindElementAtOffset(InTy, Offset, NewIndices, TD)) {
+ if (FindElementAtOffset(InTy, Offset, NewIndices)) {
Value *NGEP = cast<GEPOperator>(&GEP)->isInBounds() ?
Builder->CreateInBoundsGEP(BCI->getOperand(0), NewIndices.begin(),
NewIndices.end()) :
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