ValueTracking: Look through fneg in isKnownNeverNaN

diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
index 40e4253..4c73eca 100644 (file)
--- a/llvm/lib/Analysis/ValueTracking.cpp
+++ b/llvm/lib/Analysis/ValueTracking.cpp
@@ -3869,6 +3869,7 @@ bool llvm::isKnownNeverNaN(const Value *V, const TargetLibraryInfo *TLI,
       return true;
     case Instruction::FPTrunc:
     case Instruction::FPExt:
+    case Instruction::FNeg:
       return isKnownNeverNaN(Inst->getOperand(0), TLI, Depth + 1);
     default:
       break;

diff --git a/llvm/test/Transforms/InstSimplify/known-never-nan.ll b/llvm/test/Transforms/InstSimplify/known-never-nan.ll
index 8b24b27..d6a2924 100644 (file)
--- a/llvm/test/Transforms/InstSimplify/known-never-nan.ll
+++ b/llvm/test/Transforms/InstSimplify/known-never-nan.ll
@@ -291,9 +291,7 @@ define i1 @nnan_binary_fneg() {
 define i1 @nnan_unary_fneg() {
 ; CHECK-LABEL: @nnan_unary_fneg(
 ; CHECK-NEXT:    [[NNAN:%.*]] = call nnan double @func()
-; CHECK-NEXT:    [[OP:%.*]] = fneg double [[NNAN]]
-; CHECK-NEXT:    [[TMP:%.*]] = fcmp ord double [[OP]], [[OP]]
-; CHECK-NEXT:    ret i1 [[TMP]]
+; CHECK-NEXT:    ret i1 true
 ;
   %nnan = call nnan double @func()
   %op = fneg double %nnan