diff options
Diffstat (limited to 'llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp index 6c09600..fa3a9d2 100644 --- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp +++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp @@ -1644,6 +1644,11 @@ Value *LibCallSimplifier::replacePowWithSqrt(CallInst *Pow, IRBuilder<> &B) { (!ExpoF->isExactlyValue(0.5) && !ExpoF->isExactlyValue(-0.5))) return nullptr; + // Converting pow(X, -0.5) to 1/sqrt(X) may introduce an extra rounding step, + // so that requires fast-math-flags (afn or reassoc). + if (ExpoF->isNegative() && (!Pow->hasApproxFunc() && !Pow->hasAllowReassoc())) + return nullptr; + Sqrt = getSqrtCall(Base, Attrs, Pow->doesNotAccessMemory(), Mod, B, TLI); if (!Sqrt) return nullptr; |