Reapply 132424 with fixes.  This fixes PR10068.
rdar://problem/5993888


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132606 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.h b/lib/Target/X86/X86ISelLowering.h
index 3c8e7c1..c599c45 100644
--- a/lib/Target/X86/X86ISelLowering.h
+++ b/lib/Target/X86/X86ISelLowering.h
@@ -94,6 +94,11 @@
       // one's or all zero's.
       SETCC_CARRY,  // R = carry_bit ? ~0 : 0
 
+      /// X86 FP SETCC, implemented with CMP{cc}SS/CMP{cc}SD.
+      /// Operands are two FP values to compare; result is a mask of
+      /// 0s or 1s.  Generally DTRT for C/C++ with NaNs.
+      FSETCCss, FSETCCsd,
+
       /// X86 MOVMSK{pd|ps}, extracts sign bits of two or four FP values,
       /// result in an integer GPR.  Needs masking for scalar result.
       FGETSIGNx86,