diff options
| -rw-r--r-- | lib/Analysis/ValueTracking.cpp | 3 | ||||
| -rw-r--r-- | test/Transforms/InstCombine/sext.ll | 10 |
2 files changed, 12 insertions, 1 deletions
diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp index 33fb1e8..6c33d2d 100644 --- a/lib/Analysis/ValueTracking.cpp +++ b/lib/Analysis/ValueTracking.cpp @@ -431,7 +431,8 @@ void llvm::ComputeMaskedBits(Value *V, const APInt &Mask, } // Are we still trying to solve for the sign bit? - if (Mask.isNegative() && !KnownZero.isNegative() && !KnownOne.isNegative()){ + if (I->getOpcode() == Instruction::Add && + Mask.isNegative() && !KnownZero.isNegative() && !KnownOne.isNegative()){ OverflowingBinaryOperator *OBO = cast<OverflowingBinaryOperator>(I); if (OBO->hasNoSignedWrap()) { // Adding two positive numbers can't wrap into negative ... diff --git a/test/Transforms/InstCombine/sext.ll b/test/Transforms/InstCombine/sext.ll index 60669b7..da52d92 100644 --- a/test/Transforms/InstCombine/sext.ll +++ b/test/Transforms/InstCombine/sext.ll @@ -126,3 +126,13 @@ define void @test11(<2 x i16> %srcA, <2 x i16> %srcB, <2 x i16>* %dst) { ; CHECK-NEXT: store <2 x i16> ; CHECK-NEXT: ret } + +define i64 @test12(i32 %x) nounwind { + %shr = lshr i32 %x, 1 + %sub = sub nsw i32 0, %shr + %conv = sext i32 %sub to i64 + ret i64 %conv +; CHECK: @test12 +; CHECK: sext +; CHECK: ret +} |