[llvm-commits] [llvm] r46411 - /llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

[Chris Lattner]

Author: lattner
Date: Sun Jan 27 00:19:31 2008
New Revision: 46411

URL: http://llvm.org/viewvc/llvm-project?rev=46411&view=rev
Log:
Use fldz and fld1 for long double constants instead of a constant pool load.

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=46411&r1=46410&r2=46411&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Sun Jan 27 00:19:31 2008
@@ -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);