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-rw-r--r--contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp78
1 files changed, 50 insertions, 28 deletions
diff --git a/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index f51442a9f36d..776704d1efa9 100644
--- a/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/contrib/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -38,7 +38,8 @@ getInverseMinMaxSelectPattern(SelectPatternFlavor SPF) {
}
}
-static CmpInst::Predicate getICmpPredicateForMinMax(SelectPatternFlavor SPF) {
+static CmpInst::Predicate getCmpPredicateForMinMax(SelectPatternFlavor SPF,
+ bool Ordered=false) {
switch (SPF) {
default:
llvm_unreachable("unhandled!");
@@ -51,17 +52,22 @@ static CmpInst::Predicate getICmpPredicateForMinMax(SelectPatternFlavor SPF) {
return ICmpInst::ICMP_SGT;
case SPF_UMAX:
return ICmpInst::ICMP_UGT;
+ case SPF_FMINNUM:
+ return Ordered ? FCmpInst::FCMP_OLT : FCmpInst::FCMP_ULT;
+ case SPF_FMAXNUM:
+ return Ordered ? FCmpInst::FCMP_OGT : FCmpInst::FCMP_UGT;
}
}
static Value *generateMinMaxSelectPattern(InstCombiner::BuilderTy *Builder,
SelectPatternFlavor SPF, Value *A,
Value *B) {
- CmpInst::Predicate Pred = getICmpPredicateForMinMax(SPF);
+ CmpInst::Predicate Pred = getCmpPredicateForMinMax(SPF);
+ assert(CmpInst::isIntPredicate(Pred));
return Builder->CreateSelect(Builder->CreateICmp(Pred, A, B), A, B);
}
-/// GetSelectFoldableOperands - We want to turn code that looks like this:
+/// We want to turn code that looks like this:
/// %C = or %A, %B
/// %D = select %cond, %C, %A
/// into:
@@ -90,8 +96,8 @@ static unsigned GetSelectFoldableOperands(Instruction *I) {
}
}
-/// GetSelectFoldableConstant - For the same transformation as the previous
-/// function, return the identity constant that goes into the select.
+/// For the same transformation as the previous function, return the identity
+/// constant that goes into the select.
static Constant *GetSelectFoldableConstant(Instruction *I) {
switch (I->getOpcode()) {
default: llvm_unreachable("This cannot happen!");
@@ -110,7 +116,7 @@ static Constant *GetSelectFoldableConstant(Instruction *I) {
}
}
-/// FoldSelectOpOp - Here we have (select c, TI, FI), and we know that TI and FI
+/// Here we have (select c, TI, FI), and we know that TI and FI
/// have the same opcode and only one use each. Try to simplify this.
Instruction *InstCombiner::FoldSelectOpOp(SelectInst &SI, Instruction *TI,
Instruction *FI) {
@@ -197,8 +203,8 @@ static bool isSelect01(Constant *C1, Constant *C2) {
C2I->isOne() || C2I->isAllOnesValue();
}
-/// FoldSelectIntoOp - Try fold the select into one of the operands to
-/// facilitate further optimization.
+/// Try to fold the select into one of the operands to allow further
+/// optimization.
Instruction *InstCombiner::FoldSelectIntoOp(SelectInst &SI, Value *TrueVal,
Value *FalseVal) {
// See the comment above GetSelectFoldableOperands for a description of the
@@ -276,7 +282,7 @@ Instruction *InstCombiner::FoldSelectIntoOp(SelectInst &SI, Value *TrueVal,
return nullptr;
}
-/// foldSelectICmpAndOr - We want to turn:
+/// We want to turn:
/// (select (icmp eq (and X, C1), 0), Y, (or Y, C2))
/// into:
/// (or (shl (and X, C1), C3), y)
@@ -394,9 +400,7 @@ static Value *foldSelectCttzCtlz(ICmpInst *ICI, Value *TrueVal, Value *FalseVal,
return nullptr;
}
-/// visitSelectInstWithICmp - Visit a SelectInst that has an
-/// ICmpInst as its first operand.
-///
+/// Visit a SelectInst that has an ICmpInst as its first operand.
Instruction *InstCombiner::visitSelectInstWithICmp(SelectInst &SI,
ICmpInst *ICI) {
bool Changed = false;
@@ -595,10 +599,9 @@ Instruction *InstCombiner::visitSelectInstWithICmp(SelectInst &SI,
}
-/// CanSelectOperandBeMappingIntoPredBlock - SI is a select whose condition is a
-/// PHI node (but the two may be in different blocks). See if the true/false
-/// values (V) are live in all of the predecessor blocks of the PHI. For
-/// example, cases like this cannot be mapped:
+/// SI is a select whose condition is a PHI node (but the two may be in
+/// different blocks). See if the true/false values (V) are live in all of the
+/// predecessor blocks of the PHI. For example, cases like this can't be mapped:
///
/// X = phi [ C1, BB1], [C2, BB2]
/// Y = add
@@ -632,7 +635,7 @@ static bool CanSelectOperandBeMappingIntoPredBlock(const Value *V,
return false;
}
-/// FoldSPFofSPF - We have an SPF (e.g. a min or max) of an SPF of the form:
+/// We have an SPF (e.g. a min or max) of an SPF of the form:
/// SPF2(SPF1(A, B), C)
Instruction *InstCombiner::FoldSPFofSPF(Instruction *Inner,
SelectPatternFlavor SPF1,
@@ -745,10 +748,10 @@ Instruction *InstCombiner::FoldSPFofSPF(Instruction *Inner,
return nullptr;
}
-/// foldSelectICmpAnd - If one of the constants is zero (we know they can't
-/// both be) and we have an icmp instruction with zero, and we have an 'and'
-/// with the non-constant value and a power of two we can turn the select
-/// into a shift on the result of the 'and'.
+/// If one of the constants is zero (we know they can't both be) and we have an
+/// icmp instruction with zero, and we have an 'and' with the non-constant value
+/// and a power of two we can turn the select into a shift on the result of the
+/// 'and'.
static Value *foldSelectICmpAnd(const SelectInst &SI, ConstantInt *TrueVal,
ConstantInt *FalseVal,
InstCombiner::BuilderTy *Builder) {
@@ -926,6 +929,8 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
// (X ugt Y) ? X : Y -> (X ole Y) ? Y : X
if (FCI->hasOneUse() && FCmpInst::isUnordered(FCI->getPredicate())) {
FCmpInst::Predicate InvPred = FCI->getInversePredicate();
+ IRBuilder<>::FastMathFlagGuard FMFG(*Builder);
+ Builder->SetFastMathFlags(FCI->getFastMathFlags());
Value *NewCond = Builder->CreateFCmp(InvPred, TrueVal, FalseVal,
FCI->getName() + ".inv");
@@ -967,6 +972,8 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
// (X ugt Y) ? X : Y -> (X ole Y) ? X : Y
if (FCI->hasOneUse() && FCmpInst::isUnordered(FCI->getPredicate())) {
FCmpInst::Predicate InvPred = FCI->getInversePredicate();
+ IRBuilder<>::FastMathFlagGuard FMFG(*Builder);
+ Builder->SetFastMathFlags(FCI->getFastMathFlags());
Value *NewCond = Builder->CreateFCmp(InvPred, FalseVal, TrueVal,
FCI->getName() + ".inv");
@@ -1054,35 +1061,50 @@ Instruction *InstCombiner::visitSelectInst(SelectInst &SI) {
}
// See if we can fold the select into one of our operands.
- if (SI.getType()->isIntOrIntVectorTy()) {
+ if (SI.getType()->isIntOrIntVectorTy() || SI.getType()->isFPOrFPVectorTy()) {
if (Instruction *FoldI = FoldSelectIntoOp(SI, TrueVal, FalseVal))
return FoldI;
Value *LHS, *RHS, *LHS2, *RHS2;
Instruction::CastOps CastOp;
- SelectPatternFlavor SPF = matchSelectPattern(&SI, LHS, RHS, &CastOp);
+ SelectPatternResult SPR = matchSelectPattern(&SI, LHS, RHS, &CastOp);
+ auto SPF = SPR.Flavor;
- if (SPF) {
+ if (SelectPatternResult::isMinOrMax(SPF)) {
// Canonicalize so that type casts are outside select patterns.
if (LHS->getType()->getPrimitiveSizeInBits() !=
SI.getType()->getPrimitiveSizeInBits()) {
- CmpInst::Predicate Pred = getICmpPredicateForMinMax(SPF);
- Value *Cmp = Builder->CreateICmp(Pred, LHS, RHS);
+ CmpInst::Predicate Pred = getCmpPredicateForMinMax(SPF, SPR.Ordered);
+
+ Value *Cmp;
+ if (CmpInst::isIntPredicate(Pred)) {
+ Cmp = Builder->CreateICmp(Pred, LHS, RHS);
+ } else {
+ IRBuilder<>::FastMathFlagGuard FMFG(*Builder);
+ auto FMF = cast<FPMathOperator>(SI.getCondition())->getFastMathFlags();
+ Builder->SetFastMathFlags(FMF);
+ Cmp = Builder->CreateFCmp(Pred, LHS, RHS);
+ }
+
Value *NewSI = Builder->CreateCast(CastOp,
Builder->CreateSelect(Cmp, LHS, RHS),
SI.getType());
return ReplaceInstUsesWith(SI, NewSI);
}
+ }
+ if (SPF) {
// MAX(MAX(a, b), a) -> MAX(a, b)
// MIN(MIN(a, b), a) -> MIN(a, b)
// MAX(MIN(a, b), a) -> a
// MIN(MAX(a, b), a) -> a
- if (SelectPatternFlavor SPF2 = matchSelectPattern(LHS, LHS2, RHS2))
+ // ABS(ABS(a)) -> ABS(a)
+ // NABS(NABS(a)) -> NABS(a)
+ if (SelectPatternFlavor SPF2 = matchSelectPattern(LHS, LHS2, RHS2).Flavor)
if (Instruction *R = FoldSPFofSPF(cast<Instruction>(LHS),SPF2,LHS2,RHS2,
SI, SPF, RHS))
return R;
- if (SelectPatternFlavor SPF2 = matchSelectPattern(RHS, LHS2, RHS2))
+ if (SelectPatternFlavor SPF2 = matchSelectPattern(RHS, LHS2, RHS2).Flavor)
if (Instruction *R = FoldSPFofSPF(cast<Instruction>(RHS),SPF2,LHS2,RHS2,
SI, SPF, LHS))
return R;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 02:02:52 +0000