[llvm-commits] [llvm] r137295 - in /llvm/trunk: lib/Target/X86/X86ISelLowering.cpp test/CodeGen/X86/avx-splat.ll

[Bruno Cardoso Lopes]

Author: bruno
Date: Wed Aug 10 21:49:41 2011
New Revision: 137295

URL: http://llvm.org/viewvc/llvm-project?rev=137295&view=rev
Log:
Use the splat index to generate the desired shuffle. Otherwise we
could only get undefs and the vector shuffle becomes an undef,
generating wrong code.

Modified:
    llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
    llvm/trunk/test/CodeGen/X86/avx-splat.ll

Modified: llvm/trunk/lib/Target/X86/X86ISelLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86ISelLowering.cpp?rev=137295&r1=137294&r2=137295&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86ISelLowering.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86ISelLowering.cpp Wed Aug 10 21:49:41 2011
@@ -4125,15 +4125,15 @@
   int NumElems = SrcVT.getVectorNumElements();
 
   assert(SrcVT.is256BitVector() && "unknown howto handle vector type");
+  assert(SV->isSplat() && "shuffle must be a splat");
 
-  SmallVector<int, 4> Mask;
-  for (int i = 0; i < NumElems/2; ++i)
-    Mask.push_back(SV->getMaskElt(i));
+  int SplatIdx = SV->getSplatIndex();
+  const int Mask[4] = { SplatIdx, SplatIdx, SplatIdx, SplatIdx };
 
   EVT SVT = EVT::getVectorVT(*DAG.getContext(), SrcVT.getVectorElementType(),
                              NumElems/2);
   SDValue SV1 = DAG.getVectorShuffle(SVT, dl, V1.getOperand(1),
-                                     DAG.getUNDEF(SVT), &Mask[0]);
+                                     DAG.getUNDEF(SVT), Mask);
   SDValue InsV = Insert128BitVector(DAG.getUNDEF(SrcVT), SV1,
                                     DAG.getConstant(0, MVT::i32), DAG, dl);
 

Modified: llvm/trunk/test/CodeGen/X86/avx-splat.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/avx-splat.ll?rev=137295&r1=137294&r2=137295&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/avx-splat.ll (original)
+++ llvm/trunk/test/CodeGen/X86/avx-splat.ll Wed Aug 10 21:49:41 2011
@@ -77,3 +77,13 @@
   ret void
 }
 
+; CHECK: vpshufd  $0
+; CHECK-NEXT: vinsertf128 $1
+define <8 x float> @funcF(i32* %ptr) nounwind {
+  %val = load i32* %ptr, align 4
+  %ret6 = insertelement <8 x i32> undef, i32 %val, i32 6
+  %ret7 = insertelement <8 x i32> %ret6, i32 %val, i32 7
+  %tmp = bitcast <8 x i32> %ret7 to <8 x float>
+  ret <8 x float> %tmp
+}
+