Mark ISD::FMA as Legal instead of custom for x86 with FMA3/FMA4. Needed so that llvm.muladd can be converted to ISD::FMA for fp_contract.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168413 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 3192a43..276859b 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -1124,12 +1124,12 @@
     setOperationAction(ISD::VSELECT,           MVT::v8f32, Legal);
 
     if (Subtarget->hasFMA() || Subtarget->hasFMA4()) {
-      setOperationAction(ISD::FMA,             MVT::v8f32, Custom);
-      setOperationAction(ISD::FMA,             MVT::v4f64, Custom);
-      setOperationAction(ISD::FMA,             MVT::v4f32, Custom);
-      setOperationAction(ISD::FMA,             MVT::v2f64, Custom);
-      setOperationAction(ISD::FMA,             MVT::f32, Custom);
-      setOperationAction(ISD::FMA,             MVT::f64, Custom);
+      setOperationAction(ISD::FMA,             MVT::v8f32, Legal);
+      setOperationAction(ISD::FMA,             MVT::v4f64, Legal);
+      setOperationAction(ISD::FMA,             MVT::v4f32, Legal);
+      setOperationAction(ISD::FMA,             MVT::v2f64, Legal);
+      setOperationAction(ISD::FMA,             MVT::f32, Legal);
+      setOperationAction(ISD::FMA,             MVT::f64, Legal);
     }
 
     if (Subtarget->hasAVX2()) {