[llvm] [VectorCombine] reject out-of-bounds extract indexes in foldExtractExtract (PR #194381)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,17 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 6
+; RUN: opt -passes=vector-combine -S -mtriple=x86_64-- < %s | FileCheck %s
+
+define i8 @f() {
+; CHECK-LABEL: define i8 @f() {
+; CHECK-NEXT:  [[BB:.*:]]
+; CHECK-NEXT:    [[E:%.*]] = extractelement <8 x i8> zeroinitializer, i32 133769
+; CHECK-NEXT:    [[E6:%.*]] = extractelement <8 x i8> zeroinitializer, i32 1
+; CHECK-NEXT:    [[B:%.*]] = mul i8 [[E]], [[E6]]
+; CHECK-NEXT:    ret i8 [[B]]
+;
+BB:
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RKSimon wrote:

drop unnecessary label

https://github.com/llvm/llvm-project/pull/194381