[PATCH] D93994: [InstSimplify] Fold insertelement vec, poison, idx into vec

[Juneyoung Lee via Phabricator via llvm-commits]

aqjune added inline comments.


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Comment at: llvm/test/Transforms/SLPVectorizer/X86/alternate-int.ll:428
 ; CHECK-NEXT:    [[AB7:%.*]] = sdiv i32 [[A7]], 16
-; CHECK-NEXT:    [[TMP1:%.*]] = insertelement <8 x i32> poison, i32 [[AB1]], i32 1
-; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <8 x i32> [[TMP1]], i32 [[AB2]], i32 2
-; CHECK-NEXT:    [[R4:%.*]] = insertelement <8 x i32> [[TMP2]], i32 [[AB3]], i32 3
-; CHECK-NEXT:    [[R5:%.*]] = insertelement <8 x i32> [[R4]], i32 [[AB5]], i32 5
+; CHECK-NEXT:    [[R1:%.*]] = insertelement <8 x i32> <i32 poison, i32 poison, i32 poison, i32 poison, i32 undef, i32 poison, i32 poison, i32 poison>, i32 [[AB1]], i32 1
+; CHECK-NEXT:    [[R2:%.*]] = insertelement <8 x i32> [[R1]], i32 [[AB2]], i32 2
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I think something is happening here, I imagine some transformation is passing undef to SimplifyInsertElementInst instead of poison (because sdiv _, undef is simplified to poison) I will look into this later.


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  https://reviews.llvm.org/D93994/new/

https://reviews.llvm.org/D93994