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path: root/lib/Transforms/Scalar/InstructionCombining.cpp
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-rw-r--r--lib/Transforms/Scalar/InstructionCombining.cpp159
1 files changed, 8 insertions, 151 deletions
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 0d23e1521c..74d0971b42 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -283,8 +283,6 @@ namespace {
Instruction *visitSelectInstWithICmp(SelectInst &SI, ICmpInst *ICI);
Instruction *visitCallInst(CallInst &CI);
Instruction *visitInvokeInst(InvokeInst &II);
-
- Instruction *SliceUpIllegalIntegerPHI(PHINode &PN);
Instruction *visitPHINode(PHINode &PN);
Instruction *visitGetElementPtrInst(GetElementPtrInst &GEP);
Instruction *visitAllocaInst(AllocaInst &AI);
@@ -8085,7 +8083,8 @@ bool InstCombiner::CanEvaluateInDifferentType(Value *V, const Type *Ty,
Value *InstCombiner::EvaluateInDifferentType(Value *V, const Type *Ty,
bool isSigned) {
if (Constant *C = dyn_cast<Constant>(V))
- return ConstantExpr::getIntegerCast(C, Ty, isSigned /*Sext or ZExt*/);
+ return ConstantExpr::getIntegerCast(C, Ty,
+ isSigned /*Sext or ZExt*/);
// Otherwise, it must be an instruction.
Instruction *I = cast<Instruction>(V);
@@ -8118,7 +8117,8 @@ Value *InstCombiner::EvaluateInDifferentType(Value *V, const Type *Ty,
return I->getOperand(0);
// Otherwise, must be the same type of cast, so just reinsert a new one.
- Res = CastInst::Create(cast<CastInst>(I)->getOpcode(), I->getOperand(0),Ty);
+ Res = CastInst::Create(cast<CastInst>(I)->getOpcode(), I->getOperand(0),
+ Ty);
break;
case Instruction::Select: {
Value *True = EvaluateInDifferentType(I->getOperand(1), Ty, isSigned);
@@ -8167,17 +8167,9 @@ Instruction *InstCombiner::commonCastTransforms(CastInst &CI) {
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()) ||
- (TD && TD->isLegalInteger(CI.getType()->getPrimitiveSizeInBits())) ||
- (TD && !TD->isLegalInteger(Src->getType()->getPrimitiveSizeInBits())))
- if (Instruction *NV = FoldOpIntoPhi(CI))
- return NV;
-
- }
+ if (isa<PHINode>(Src))
+ if (Instruction *NV = FoldOpIntoPhi(CI))
+ return NV;
return 0;
}
@@ -8516,7 +8508,7 @@ Instruction *InstCombiner::visitTrunc(TruncInst &CI) {
return BinaryOperator::CreateLShr(V1, V2);
}
}
-
+
return 0;
}
@@ -10894,15 +10886,6 @@ Instruction *InstCombiner::FoldPHIArgOpIntoPHI(PHINode &PN) {
if (isa<CastInst>(FirstInst)) {
CastSrcTy = FirstInst->getOperand(0)->getType();
-
- // If this is a legal integer PHI node, and pulling the operation through
- // would cause it to be an illegal integer PHI, don't do the transformation.
- if (!TD ||
- (isa<IntegerType>(PN.getType()) &&
- isa<IntegerType>(CastSrcTy) &&
- TD->isLegalInteger(PN.getType()->getPrimitiveSizeInBits()) &&
- !TD->isLegalInteger(CastSrcTy->getPrimitiveSizeInBits())))
- return 0;
} else if (isa<BinaryOperator>(FirstInst) || isa<CmpInst>(FirstInst)) {
// Can fold binop, compare or shift here if the RHS is a constant,
// otherwise call FoldPHIArgBinOpIntoPHI.
@@ -11015,123 +10998,6 @@ static bool PHIsEqualValue(PHINode *PN, Value *NonPhiInVal,
}
-namespace {
-struct PHIUsageRecord {
- unsigned Shift; // The amount shifted.
- Instruction *Inst; // The trunc instruction.
-
- PHIUsageRecord(unsigned Sh, Instruction *User) : Shift(Sh), Inst(User) {}
-
- bool operator<(const PHIUsageRecord &RHS) const {
- if (Shift < RHS.Shift) return true;
- return Shift == RHS.Shift &&
- Inst->getType()->getPrimitiveSizeInBits() <
- RHS.Inst->getType()->getPrimitiveSizeInBits();
- }
-};
-}
-
-
-/// SliceUpIllegalIntegerPHI - This is an integer PHI and we know that it has an
-/// illegal type: see if it is only used by trunc or trunc(lshr) operations. If
-/// so, we split the PHI into the various pieces being extracted. This sort of
-/// thing is introduced when SROA promotes an aggregate to large integer values.
-///
-/// TODO: The user of the trunc may be an bitcast to float/double/vector or an
-/// inttoptr. We should produce new PHIs in the right type.
-///
-Instruction *InstCombiner::SliceUpIllegalIntegerPHI(PHINode &PN) {
- SmallVector<PHIUsageRecord, 16> PHIUsers;
-
- for (Value::use_iterator UI = PN.use_begin(), E = PN.use_end();
- UI != E; ++UI) {
- Instruction *User = cast<Instruction>(*UI);
-
- // The PHI can use itself.
- if (User == &PN)
- continue;
-
- // Truncates are always ok.
- if (isa<TruncInst>(User)) {
- PHIUsers.push_back(PHIUsageRecord(0, User));
- continue;
- }
-
- // Otherwise it must be a lshr which can only be used by one trunc.
- if (User->getOpcode() != Instruction::LShr ||
- !User->hasOneUse() || !isa<TruncInst>(User->use_back()) ||
- !isa<ConstantInt>(User->getOperand(1)))
- return 0;
-
- unsigned Shift = cast<ConstantInt>(User->getOperand(1))->getZExtValue();
- PHIUsers.push_back(PHIUsageRecord(Shift, User->use_back()));
- }
-
- // If we have no users, they must be all self uses, just nuke the PHI.
- if (PHIUsers.empty())
- return ReplaceInstUsesWith(PN, UndefValue::get(PN.getType()));
-
- // If this phi node is transformable, create new PHIs for all the pieces
- // extracted out of it. First, sort the users by their offset and size.
- array_pod_sort(PHIUsers.begin(), PHIUsers.end());
-
-
- DenseMap<BasicBlock*, Value*> PredValues;
-
- unsigned UserI = 0, UserE = PHIUsers.size();
- while (1) {
- assert(UserI != UserE && "Iteration fail, loop below should catch this");
-
- unsigned Offset = PHIUsers[UserI].Shift;
- const Type *Ty = PHIUsers[UserI].Inst->getType();
-
- // Create the new PHI node for this user.
- PHINode *EltPHI =
- PHINode::Create(Ty, PN.getName()+".off"+Twine(Offset), &PN);
-
- for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
- BasicBlock *Pred = PN.getIncomingBlock(i);
- Value *&PredVal = PredValues[Pred];
-
- // If we already have a value for this predecessor, reuse it.
- if (PredVal) {
- EltPHI->addIncoming(PredVal, Pred);
- continue;
- }
-
- // Handle the PHI self-reuse case.
- Value *InVal = PN.getIncomingValue(i);
- if (InVal == &PN) {
- PredVal = EltPHI;
- EltPHI->addIncoming(PredVal, Pred);
- continue;
- }
-
- // Otherwise, do an extract in the predecessor.
- Builder->SetInsertPoint(Pred, Pred->getTerminator());
- if (Offset)
- InVal = Builder->CreateLShr(InVal, ConstantInt::get(InVal->getType(),
- Offset), "extract");
- InVal = Builder->CreateTrunc(InVal, Ty, "extract.t");
- PredVal = InVal;
- EltPHI->addIncoming(PredVal, Pred);
- }
- PredValues.clear();
-
- // Now that we have a new PHI node, replace all uses of this piece of the
- // PHI with the one new PHI.
- while (PHIUsers[UserI].Shift == Offset &&
- PHIUsers[UserI].Inst->getType() == Ty) {
- ReplaceInstUsesWith(*PHIUsers[UserI].Inst, EltPHI);
-
- // If we replaced the last PHI user, we're done. Just replace all the
- // remaining uses of the PHI (self uses and the lshrs with undefs.
- if (++UserI == UserE)
- return ReplaceInstUsesWith(PN, UndefValue::get(PN.getType()));
- }
- }
-}
-
// PHINode simplification
//
Instruction *InstCombiner::visitPHINode(PHINode &PN) {
@@ -11237,15 +11103,6 @@ Instruction *InstCombiner::visitPHINode(PHINode &PN) {
}
}
- // If this is an integer PHI and we know that it has an illegal type, see if
- // it is only used by trunc or trunc(lshr) operations. If so, we split the
- // PHI into the various pieces being extracted. This sort of thing is
- // introduced when SROA promotes an aggregate to a single large integer type.
- if (isa<IntegerType>(PN.getType()) && TD &&
- !TD->isLegalInteger(PN.getType()->getPrimitiveSizeInBits()))
- if (Instruction *Res = SliceUpIllegalIntegerPHI(PN))
- return Res;
-
return 0;
}
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2025-06-23 02:28:28 +0000