Use fldz and fld1 for long double constants instead of a constant pool load.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46411 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index f07793b..90408c8 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -455,7 +455,20 @@
addRegisterClass(MVT::f80, X86::RFP80RegisterClass);
setOperationAction(ISD::UNDEF, MVT::f80, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f80, Expand);
- setOperationAction(ISD::ConstantFP, MVT::f80, Expand);
+ {
+ setOperationAction(ISD::ConstantFP, MVT::f80, Expand);
+ APFloat TmpFlt(+0.0);
+ TmpFlt.convert(APFloat::x87DoubleExtended, APFloat::rmNearestTiesToEven);
+ addLegalFPImmediate(TmpFlt); // FLD0
+ TmpFlt.changeSign();
+ addLegalFPImmediate(TmpFlt); // FLD0/FCHS
+ APFloat TmpFlt2(+1.0);
+ TmpFlt2.convert(APFloat::x87DoubleExtended, APFloat::rmNearestTiesToEven);
+ addLegalFPImmediate(TmpFlt2); // FLD1
+ TmpFlt2.changeSign();
+ addLegalFPImmediate(TmpFlt2); // FLD1/FCHS
+ }
+
if (!UnsafeFPMath) {
setOperationAction(ISD::FSIN , MVT::f80 , Expand);
setOperationAction(ISD::FCOS , MVT::f80 , Expand);