[PowerPC] Only legalize FNEARBYINT with unsafe fp math

Commit 0f0330a78709 legalized these nodes on PPC without consideration of
unsafe math which means that we get inexact exceptions raised for nearbyint.
Since this doesn't conform to the standard, switch this legalization to depend
on unsafe fp math.

1 files changed, 7 insertions, 2 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 9fab29dded7..df2234eea28 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -782,17 +782,22 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
       }
       setOperationAction(ISD::EXTRACT_VECTOR_ELT, MVT::v2f64, Legal);
 
+      // The nearbyint variants are not allowed to raise the inexact exception
+      // so we can only code-gen them with unsafe math.
+      if (TM.Options.UnsafeFPMath) {
+        setOperationAction(ISD::FNEARBYINT, MVT::f64, Legal);
+        setOperationAction(ISD::FNEARBYINT, MVT::f32, Legal);
+      }
+
       setOperationAction(ISD::FFLOOR, MVT::v2f64, Legal);
       setOperationAction(ISD::FCEIL, MVT::v2f64, Legal);
       setOperationAction(ISD::FTRUNC, MVT::v2f64, Legal);
       setOperationAction(ISD::FNEARBYINT, MVT::v2f64, Legal);
       setOperationAction(ISD::FROUND, MVT::v2f64, Legal);
-      setOperationAction(ISD::FNEARBYINT, MVT::f64, Legal);
       setOperationAction(ISD::FROUND, MVT::f64, Legal);
 
       setOperationAction(ISD::FNEARBYINT, MVT::v4f32, Legal);
       setOperationAction(ISD::FROUND, MVT::v4f32, Legal);
-      setOperationAction(ISD::FNEARBYINT, MVT::f32, Legal);
       setOperationAction(ISD::FROUND, MVT::f32, Legal);
 
       setOperationAction(ISD::MUL, MVT::v2f64, Legal);