[SimplifyLibCalls] propagate FMF when folding pow(x, 2.0) call (PR35601)
This should fix the larger problem with sqrt shown in:
https://bugs.llvm.org/show_bug.cgi?id=35601
llvm-svn: 320310
diff --git a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
index c392492..273a5e7 100644
--- a/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
+++ b/llvm/lib/Transforms/Utils/SimplifyLibCalls.cpp
@@ -1206,8 +1206,13 @@
if (Op2C->isExactlyValue(1.0)) // pow(x, 1.0) -> x
return Op1;
- if (Op2C->isExactlyValue(2.0)) // pow(x, 2.0) -> x*x
+ if (Op2C->isExactlyValue(2.0)) {
+ // pow(x, 2.0) --> x * x
+ IRBuilder<>::FastMathFlagGuard Guard(B);
+ B.setFastMathFlags(CI->getFastMathFlags());
return B.CreateFMul(Op1, Op1, "pow2");
+ }
+ // FIXME: This should propagate the FMF of the call to the fdiv.
if (Op2C->isExactlyValue(-1.0)) // pow(x, -1.0) -> 1.0/x
return B.CreateFDiv(ConstantFP::get(CI->getType(), 1.0), Op1, "powrecip");