[PATCH] D127119: [SLP]Fix undef handling in gather function.

[Vasileios Porpodas via Phabricator via llvm-commits]

vporpo added inline comments.


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Comment at: llvm/test/Transforms/SLPVectorizer/X86/diamond_broadcast_extra_shuffle.ll:37
 ; CHECK-NEXT:    [[TMP0:%.*]] = insertelement <4 x i32> poison, i32 [[LD]], i32 0
-; CHECK-NEXT:    [[SHUFFLE:%.*]] = shufflevector <4 x i32> [[TMP0]], <4 x i32> poison, <4 x i32> zeroinitializer
-; CHECK-NEXT:    [[TMP1:%.*]] = mul <4 x i32> [[SHUFFLE]], [[SHUFFLE]]
+; CHECK-NEXT:    [[SHUFFLE:%.*]] = shufflevector <4 x i32> [[TMP0]], <4 x i32> poison, <4 x i32> <i32 0, i32 0, i32 0, i32 undef>
+; CHECK-NEXT:    [[SHUFFLE1:%.*]] = shufflevector <4 x i32> [[TMP0]], <4 x i32> poison, <4 x i32> zeroinitializer
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Doesn't an undef here mean that lane 4 can potentially be poison? Wouldn't that be incorrect?


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D127119/new/

https://reviews.llvm.org/D127119