[llvm] [SROA] Fix assertion failure when promoting self-referential load/store (PR #208826)

[Yonah Goldberg via llvm-commits]

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@@ -0,0 +1,22 @@
+; RUN: opt --passes=sroa %s -S -o - 2>&1 | FileCheck %s
+
+; Ensure no crash when a store's value operand is the load being promoted,
+; creating a self-referential cycle in unreachable code.
+
+target triple = "x86_64-unknown-linux-gnu"
+
+define fastcc i32 @func(i64 %iv) {
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YonahGoldberg wrote:

probably don't need fastcc either.

https://github.com/llvm/llvm-project/pull/208826