[llvm] [Scalarizer] Fix out-of-bounds crash (PR #180359)

[Nikita Popov via llvm-commits]

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@@ -16,3 +16,12 @@ define i32 @f1(ptr %src, i32 %index) {
   %val2 = extractelement <4 x i32> %val1, i32 3
   ret i32 %val2
 }
+
+; Test that out-of-bounds extractelement doesn't crash the scalarizer.
+define void @oob_extract() {
+; ALL-LABEL: @oob_extract(
+; ALL-NEXT:    ret void
+;
+  %E = extractelement <4 x ptr> zeroinitializer, i32 100
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nikic wrote:

Please return %E from the function, otherwise it's unclear what the transform is actually doing now.

https://github.com/llvm/llvm-project/pull/180359