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-rw-r--r--llvm/lib/Transforms/Utils/SimplifyIndVar.cpp39
1 files changed, 20 insertions, 19 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp b/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
index 9b91d74..a618d72 100644
--- a/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyIndVar.cpp
@@ -1383,32 +1383,33 @@ WidenIV::getExtendedOperandRecurrence(WidenIV::NarrowIVDefUse DU) {
DU.NarrowUse->getOperand(0) == DU.NarrowDef ? 1 : 0;
assert(DU.NarrowUse->getOperand(1-ExtendOperIdx) == DU.NarrowDef && "bad DU");
- const SCEV *ExtendOperExpr = nullptr;
const OverflowingBinaryOperator *OBO =
cast<OverflowingBinaryOperator>(DU.NarrowUse);
ExtendKind ExtKind = getExtendKind(DU.NarrowDef);
- if (ExtKind == ExtendKind::Sign && OBO->hasNoSignedWrap())
- ExtendOperExpr = SE->getSignExtendExpr(
- SE->getSCEV(DU.NarrowUse->getOperand(ExtendOperIdx)), WideType);
- else if (ExtKind == ExtendKind::Zero && OBO->hasNoUnsignedWrap())
- ExtendOperExpr = SE->getZeroExtendExpr(
- SE->getSCEV(DU.NarrowUse->getOperand(ExtendOperIdx)), WideType);
- else if (DU.NeverNegative) {
+ if (!(ExtKind == ExtendKind::Sign && OBO->hasNoSignedWrap()) &&
+ !(ExtKind == ExtendKind::Zero && OBO->hasNoUnsignedWrap())) {
+ ExtKind = ExtendKind::Unknown;
+
// For a non-negative NarrowDef, we can choose either type of
// extension. We want to use the current extend kind if legal
// (see above), and we only hit this code if we need to check
// the opposite case.
- if (OBO->hasNoSignedWrap()) {
- ExtKind = ExtendKind::Sign;
- ExtendOperExpr = SE->getSignExtendExpr(
- SE->getSCEV(DU.NarrowUse->getOperand(ExtendOperIdx)), WideType);
- } else if (OBO->hasNoUnsignedWrap()) {
- ExtKind = ExtendKind::Zero;
- ExtendOperExpr = SE->getZeroExtendExpr(
- SE->getSCEV(DU.NarrowUse->getOperand(ExtendOperIdx)), WideType);
- } else
- return {nullptr, ExtendKind::Unknown};
- } else
+ if (DU.NeverNegative) {
+ if (OBO->hasNoSignedWrap()) {
+ ExtKind = ExtendKind::Sign;
+ } else if (OBO->hasNoUnsignedWrap()) {
+ ExtKind = ExtendKind::Zero;
+ }
+ }
+ }
+
+ const SCEV *ExtendOperExpr =
+ SE->getSCEV(DU.NarrowUse->getOperand(ExtendOperIdx));
+ if (ExtKind == ExtendKind::Sign)
+ ExtendOperExpr = SE->getSignExtendExpr(ExtendOperExpr, WideType);
+ else if (ExtKind == ExtendKind::Zero)
+ ExtendOperExpr = SE->getZeroExtendExpr(ExtendOperExpr, WideType);
+ else
return {nullptr, ExtendKind::Unknown};
// When creating this SCEV expr, don't apply the current operations NSW or NUW