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path: root/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
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Diffstat (limited to 'llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp')
-rw-r--r--llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp29
1 files changed, 0 insertions, 29 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index b6b3a95..87000a1 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -2934,32 +2934,6 @@ static Instruction *foldSelectWithSRem(SelectInst &SI, InstCombinerImpl &IC,
return nullptr;
}
-static Value *foldSelectWithFrozenICmp(SelectInst &Sel, InstCombiner::BuilderTy &Builder) {
- FreezeInst *FI = dyn_cast<FreezeInst>(Sel.getCondition());
- if (!FI)
- return nullptr;
-
- Value *Cond = FI->getOperand(0);
- Value *TrueVal = Sel.getTrueValue(), *FalseVal = Sel.getFalseValue();
-
- // select (freeze(x == y)), x, y --> y
- // select (freeze(x != y)), x, y --> x
- // The freeze should be only used by this select. Otherwise, remaining uses of
- // the freeze can observe a contradictory value.
- // c = freeze(x == y) ; Let's assume that y = poison & x = 42; c is 0 or 1
- // a = select c, x, y ;
- // f(a, c) ; f(poison, 1) cannot happen, but if a is folded
- // ; to y, this can happen.
- CmpPredicate Pred;
- if (FI->hasOneUse() &&
- match(Cond, m_c_ICmp(Pred, m_Specific(TrueVal), m_Specific(FalseVal))) &&
- (Pred == ICmpInst::ICMP_EQ || Pred == ICmpInst::ICMP_NE)) {
- return Pred == ICmpInst::ICMP_EQ ? FalseVal : TrueVal;
- }
-
- return nullptr;
-}
-
/// Given that \p CondVal is known to be \p CondIsTrue, try to simplify \p SI.
static Value *simplifyNestedSelectsUsingImpliedCond(SelectInst &SI,
Value *CondVal,
@@ -4446,9 +4420,6 @@ Instruction *InstCombinerImpl::visitSelectInst(SelectInst &SI) {
if (Instruction *PN = foldSelectToPhi(SI, DT, Builder))
return replaceInstUsesWith(SI, PN);
- if (Value *Fr = foldSelectWithFrozenICmp(SI, Builder))
- return replaceInstUsesWith(SI, Fr);
-
if (Value *V = foldRoundUpIntegerWithPow2Alignment(SI, Builder))
return replaceInstUsesWith(SI, V);