[llvm] r208666 - Fix type of shuffle resulted from shuffle merge.

[Serge Pavlov]

Author: sepavloff
Date: Tue May 13 01:07:21 2014
New Revision: 208666

URL: http://llvm.org/viewvc/llvm-project?rev=208666&view=rev
Log:
Fix type of shuffle resulted from shuffle merge.

This fix resolves PR19730.

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
    llvm/trunk/test/Transforms/InstCombine/vec_shuffle.ll

Modified: llvm/trunk/lib/Transforms/InstCombine/InstCombineVectorOps.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstCombineVectorOps.cpp?rev=208666&r1=208665&r2=208666&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstCombineVectorOps.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstCombineVectorOps.cpp Tue May 13 01:07:21 2014
@@ -1114,12 +1114,10 @@ Instruction *InstCombiner::visitShuffleV
 
   // If the result mask is an identity, replace uses of this instruction with
   // corresponding argument.
-  if (VWidth == LHSWidth) {
-    bool isLHSID, isRHSID;
-    RecognizeIdentityMask(newMask, isLHSID, isRHSID);
-    if (isLHSID) return ReplaceInstUsesWith(SVI, newLHS);
-    if (isRHSID) return ReplaceInstUsesWith(SVI, newRHS);
-  }
+  bool isLHSID, isRHSID;
+  RecognizeIdentityMask(newMask, isLHSID, isRHSID);
+  if (isLHSID && VWidth == LHSOp0Width) return ReplaceInstUsesWith(SVI, newLHS);
+  if (isRHSID && VWidth == RHSOp0Width) return ReplaceInstUsesWith(SVI, newRHS);
 
   return MadeChange ? &SVI : nullptr;
 }

Modified: llvm/trunk/test/Transforms/InstCombine/vec_shuffle.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/InstCombine/vec_shuffle.ll?rev=208666&r1=208665&r2=208666&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/InstCombine/vec_shuffle.ll (original)
+++ llvm/trunk/test/Transforms/InstCombine/vec_shuffle.ll Tue May 13 01:07:21 2014
@@ -386,3 +386,11 @@ define <4 x i16> @pr19717a(<8 x i16> %in
   %mul = mul <4 x i16> %shuffle, %shuffle1
   ret <4 x i16> %mul
 }
+
+define <8 x i8> @pr19730(<16 x i8> %in0) {
+; CHECK-LABEL: @pr19730(
+; CHECK: shufflevector
+  %shuffle = shufflevector <16 x i8> %in0, <16 x i8> undef, <8 x i32> <i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0>
+  %shuffle1 = shufflevector <8 x i8> %shuffle, <8 x i8> undef, <8 x i32> <i32 7, i32 6, i32 5, i32 4, i32 3, i32 2, i32 1, i32 0>
+  ret <8 x i8> %shuffle1
+}