Add strictfp attribute to prevent unwanted optimizations of libm calls

Differential Revision: https://reviews.llvm.org/D34163

llvm-svn: 310885

1 files changed, 3 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index c7da2460356..4c8c470347b 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -6555,10 +6555,10 @@ void SelectionDAGBuilder::visitCall(const CallInst &I) {
 
     // Check for well-known libc/libm calls.  If the function is internal, it
     // can't be a library call.  Don't do the check if marked as nobuiltin for
-    // some reason.
+    // some reason or the call site requires strict floating point semantics.
     LibFunc Func;
-    if (!I.isNoBuiltin() && !F->hasLocalLinkage() && F->hasName() &&
-        LibInfo->getLibFunc(*F, Func) &&
+    if (!I.isNoBuiltin() && !I.isStrictFP() && !F->hasLocalLinkage() &&
+        F->hasName() && LibInfo->getLibFunc(*F, Func) &&
         LibInfo->hasOptimizedCodeGen(Func)) {
       switch (Func) {
       default: break;