[llvm] r211955 - [x86] Fix another bug hit when bootstrapping with the new shuffle

[Chandler Carruth]

Author: chandlerc
Date: Fri Jun 27 15:07:40 2014
New Revision: 211955

URL: http://llvm.org/viewvc/llvm-project?rev=211955&view=rev
Log:
[x86] Fix another bug hit when bootstrapping with the new shuffle
lowering.

For maximum irony, I had already discovered this bug, diagnosed it, and
left FIXMEs about it in the test cases. =[ I just failed to go back over
those until after i had reduced a bootstrap miscompile down to a single
TU, stared at the assembly for an hour, and figured out the bug. Again.

Oh well.

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/vector-shuffle-128-v4.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=211955&r1=211954&r2=211955&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Fri Jun 27 15:07:40 2014
@@ -7105,7 +7105,7 @@ static SDValue lowerV4F32VectorShuffle(S
 
       // Now we do a normal shuffle of V1 by giving V1 as both operands to
       // a blend.
-      HighV = V1;
+      LowV = HighV = V1;
       NewMask[0] = Mask[0] < 4 ? 0 : 2;
       NewMask[1] = Mask[0] < 4 ? 2 : 0;
       NewMask[2] = Mask[2] < 4 ? 1 : 3;

Modified: llvm/trunk/test/CodeGen/X86/vector-shuffle-128-v4.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/vector-shuffle-128-v4.ll?rev=211955&r1=211954&r2=211955&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/vector-shuffle-128-v4.ll (original)
+++ llvm/trunk/test/CodeGen/X86/vector-shuffle-128-v4.ll Fri Jun 27 15:07:40 2014
@@ -146,10 +146,8 @@ define <4 x i32> @shuffle_v4i32_0145(<4
 }
 define <4 x i32> @shuffle_v4i32_0451(<4 x i32> %a, <4 x i32> %b) {
 ; CHECK-SSE2-LABEL: @shuffle_v4i32_0451
-; CHECK-SSE2:         movaps %xmm0, %xmm2
-; CHECK-SSE2-NEXT:    shufps {{.*}} # xmm2 = xmm2[0,1],xmm1[0,1]
-; FIXME: This is wrong!!! xmm0 = xmm2[0,2],xmm2[3,1] would be correct....
-; CHECK-SSE2-NEXT:    shufps {{.*}} # xmm0 = xmm0[0,2],xmm2[3,1]
+; CHECK-SSE2:         shufps {{.*}} # xmm0 = xmm0[0,1],xmm1[0,1]
+; CHECK-SSE2-NEXT:    shufps {{.*}} # xmm0 = xmm0[0,2,3,1]
 ; CHECK-SSE2-NEXT:    retq
   %shuffle = shufflevector <4 x i32> %a, <4 x i32> %b, <4 x i32> <i32 0, i32 4, i32 5, i32 1>
   ret <4 x i32> %shuffle
@@ -164,10 +162,8 @@ define <4 x i32> @shuffle_v4i32_4501(<4
 }
 define <4 x i32> @shuffle_v4i32_4015(<4 x i32> %a, <4 x i32> %b) {
 ; CHECK-SSE2-LABEL: @shuffle_v4i32_4015
-; CHECK-SSE2:         movaps %xmm0, %xmm2
-; CHECK-SSE2-NEXT:    shufps {{.*}} # xmm2 = xmm2[0,1],xmm1[0,1]
-; FIXME: This is wrong!!! xmm0 = xmm2[0,2],xmm2[3,1] would be correct....
-; CHECK-SSE2-NEXT:    shufps {{.*}} # xmm0 = xmm0[2,0],xmm2[1,3]
+; CHECK-SSE2:         shufps {{.*}} # xmm0 = xmm0[0,1],xmm1[0,1]
+; CHECK-SSE2-NEXT:    shufps {{.*}} # xmm0 = xmm0[2,0,1,3]
 ; CHECK-SSE2-NEXT:    retq
   %shuffle = shufflevector <4 x i32> %a, <4 x i32> %b, <4 x i32> <i32 4, i32 0, i32 1, i32 5>
   ret <4 x i32> %shuffle