[llvm] Reland "[Support] Assert that DomTree nodes share parent"" (PR #102782)

[Alexis Engelke via llvm-commits]

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@@ -0,0 +1,46 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -mtriple=x86_64 -passes=slp-vectorizer < %s | FileCheck %s
+
+; Test that SLP vectorize doesn't crash if a stored constant is used in multiple
+; functions.
+
+define void @_Z1hPfl() {
+; CHECK-LABEL: define void @_Z1hPfl() {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[TMP0:%.*]] = getelementptr i8, ptr null, i64 28
+; CHECK-NEXT:    store <2 x float> <float 0.000000e+00, float 1.000000e+00>, ptr [[TMP0]], align 4
+; CHECK-NEXT:    ret void
+;
+entry:
+  %0 = getelementptr i8, ptr null, i64 28
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aengelke wrote:

It's iterating over the ConstantData users. I'm not familiar with SLP, please advise how to fix the larger problem. (If iterating over such users is not allowed, why is there no assertion for this?)

https://github.com/llvm/llvm-project/pull/102782