Please use GitHub pull requests for new patches. Phabricator shutdown timeline

Differential D112283 Diff 381435 llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp

Changeset View

Standalone View

llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp

Show First 20 Lines • Show All 2,676 Lines • ▼ Show 20 Lines	if (*Res == true) {
else		else
// select op, true, (select cond, A, B) => select op, true, B		// select op, true, (select cond, A, B) => select op, true, B
// or op, (select cond, A, B) => select op, true, B		// or op, (select cond, A, B) => select op, true, B
// if op = false implies condval = false.		// if op = false implies condval = false.
return SelectInst::Create(Op, One, B);		return SelectInst::Create(Op, One, B);
}		}
}		}

		static FastMathFlags getFMFforSel(SelectInst &SI) {
		Value *TrueVal = SI.getTrueValue();
		Value *FalseVal = SI.getFalseValue();
		FastMathFlags FMF;
		FMF.set();

		if (auto *V = dyn_cast<FPMathOperator>(TrueVal))
		FMF &= V->getFastMathFlags();
		else
		FMF &= FastMathFlags::getFromFuncAttr(SI.getFunction());

		if (auto *V = dyn_cast<FPMathOperator>(FalseVal))
		FMF &= V->getFastMathFlags();
		else
		FMF &= FastMathFlags::getFromFuncAttr(SI.getFunction());

		// This is probably not needed.
		// Value *CondVal = SI.getCondition();
		// if (auto *V = dyn_cast<FPMathOperator>(CondVal))
		// FMF &= V->getFastMathFlags();
		// else
		// FMF &= FastMathFlags::getFromFuncAttr(SI.getFunction());

		return FMF;
		}

Instruction *InstCombinerImpl::visitSelectInst(SelectInst &SI) {		Instruction *InstCombinerImpl::visitSelectInst(SelectInst &SI) {
Value *CondVal = SI.getCondition();		Value *CondVal = SI.getCondition();
Value *TrueVal = SI.getTrueValue();		Value *TrueVal = SI.getTrueValue();
Value *FalseVal = SI.getFalseValue();		Value *FalseVal = SI.getFalseValue();
Type *SelType = SI.getType();		Type *SelType = SI.getType();

// FIXME: Remove this workaround when freeze related patches are done.		// FIXME: Remove this workaround when freeze related patches are done.
// For select with undef operand which feeds into an equality comparison,		// For select with undef operand which feeds into an equality comparison,
Show All 16 Lines	if (Value *V = SimplifySelectInst(CondVal, TrueVal, FalseVal,
return replaceInstUsesWith(SI, V);		return replaceInstUsesWith(SI, V);

if (Instruction *I = canonicalizeSelectToShuffle(SI))		if (Instruction *I = canonicalizeSelectToShuffle(SI))
return I;		return I;

if (Instruction I = canonicalizeScalarSelectOfVecs(SI, this))		if (Instruction I = canonicalizeScalarSelectOfVecs(SI, this))
return I;		return I;

		// If the select does not have any FMFs then use the intersection
		// of it's operand's FMFs.
		if (isa<FPMathOperator>(SI) && SI.getFastMathFlags().none()) {
		FastMathFlags FMF = getFMFforSel(SI);
		if (FMF.any()) {
		SI.setFastMathFlags(getFMFforSel(SI));
		return &SI;
		}
		}

CmpInst::Predicate Pred;		CmpInst::Predicate Pred;

// Avoid potential infinite loops by checking for non-constant condition.		// Avoid potential infinite loops by checking for non-constant condition.
// TODO: Can we assert instead by improving canonicalizeSelectToShuffle()?		// TODO: Can we assert instead by improving canonicalizeSelectToShuffle()?
// Scalar select must have simplified?		// Scalar select must have simplified?
if (SelType->isIntOrIntVectorTy(1) && !isa<Constant>(CondVal) &&		if (SelType->isIntOrIntVectorTy(1) && !isa<Constant>(CondVal) &&
TrueVal->getType() == CondVal->getType()) {		TrueVal->getType() == CondVal->getType()) {
// Folding select to and/or i1 isn't poison safe in general. impliesPoison		// Folding select to and/or i1 isn't poison safe in general. impliesPoison
▲ Show 20 Lines • Show All 592 Lines • Show Last 20 Lines