[llvm] [llvm][opt][Transforms] Preserve AMDGPU atomic metadata (PR #140314)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,42 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+;; Test to ensure that AMDGPU atomic related metadata is not dropped when
+;; instructions are sunk. Currently the metadata from the first instruction
+;; is kept, which prevents full loss of optimisation information.
+
+; RUN: opt < %s -passes=simplifycfg -passes=simplifycfg -sink-common-insts -S | FileCheck %s
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arsenm wrote:

Why run it twice 

https://github.com/llvm/llvm-project/pull/140314