[llvm] r248415 - [x86] replace integer 'xor' ops with packed SSE FP 'xor' ops when operating on FP scalars

[Sanjay Patel via llvm-commits]

Author: spatel
Date: Wed Sep 23 13:33:42 2015
New Revision: 248415

URL: http://llvm.org/viewvc/llvm-project?rev=248415&view=rev
Log:
[x86] replace integer 'xor' ops with packed SSE FP 'xor' ops when operating on FP scalars

Turn this:

movd %xmm0, %eax
movd %xmm1, %ecx
xorl %eax, %ecx
movd %ecx, %xmm0

into this:

xorps %xmm1, %xmm0

This is related to, but does not solve:
https://llvm.org/bugs/show_bug.cgi?id=22428

This is an extension of:
http://reviews.llvm.org/rL248395

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/fp-logic.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=248415&r1=248414&r2=248415&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Wed Sep 23 13:33:42 2015
@@ -24787,6 +24787,9 @@ static SDValue PerformXorCombine(SDNode
     if (SDValue RV = performIntegerAbsCombine(N, DAG))
       return RV;
 
+  if (SDValue FPLogic = convertIntLogicToFPLogic(N, DAG, Subtarget))
+    return FPLogic;
+
   return SDValue();
 }
 

Modified: llvm/trunk/test/CodeGen/X86/fp-logic.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/fp-logic.ll?rev=248415&r1=248414&r2=248415&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/fp-logic.ll (original)
+++ llvm/trunk/test/CodeGen/X86/fp-logic.ll Wed Sep 23 13:33:42 2015
@@ -183,10 +183,7 @@ define float @or(float %x, float %y) {
 define float @xor(float %x, float %y) {
 ; CHECK-LABEL: xor:
 ; CHECK:       # BB#0:
-; CHECK-NEXT:    movd %xmm0, %eax
-; CHECK-NEXT:    movd %xmm1, %ecx
-; CHECK-NEXT:    xorl %eax, %ecx
-; CHECK-NEXT:    movd %ecx, %xmm0
+; CHECK-NEXT:    xorps %xmm1, %xmm0
 ; CHECK-NEXT:    retq
 
   %bc1 = bitcast float %x to i32