Bring r254336 back:

[oota-llvm.git] / lib / Transforms / Utils / LoopUtils.cpp

diff --git a/lib/Transforms/Utils/LoopUtils.cpp b/lib/Transforms/Utils/LoopUtils.cpp
index a8d20c65c1545362853911f456fc3e8e8c8c9ae2..e03880526bfa6cbf2182142fa27396d2b8a835e3 100644 (file)
--- a/lib/Transforms/Utils/LoopUtils.cpp
+++ b/lib/Transforms/Utils/LoopUtils.cpp
@@ -12,13 +12,13 @@
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Analysis/ScalarEvolution.h"
+#include "llvm/Analysis/ScalarEvolutionExpressions.h"
 #include "llvm/IR/Instructions.h"
+#include "llvm/IR/Module.h"
 #include "llvm/IR/PatternMatch.h"
 #include "llvm/IR/ValueHandle.h"
 #include "llvm/Support/Debug.h"
-#include "llvm/Analysis/ScalarEvolution.h"
-#include "llvm/Analysis/ScalarEvolutionExpressions.h"
-#include "llvm/IR/Module.h"
 #include "llvm/Transforms/Utils/LoopUtils.h"
 
 using namespace llvm;
@@ -594,6 +594,13 @@ Value *RecurrenceDescriptor::createMinMaxOp(IRBuilder<> &Builder,
     break;
   }
 
+  // We only match FP sequences with unsafe algebra, so we can unconditionally
+  // set it on any generated instructions.
+  IRBuilder<>::FastMathFlagGuard FMFG(Builder);
+  FastMathFlags FMF;
+  FMF.setUnsafeAlgebra();
+  Builder.SetFastMathFlags(FMF);
+
   Value *Cmp;
   if (RK == MRK_FloatMin || RK == MRK_FloatMax)
     Cmp = Builder.CreateFCmp(P, Left, Right, "rdx.minmax.cmp");