[llvm] [AArch64][InstCombine] Eliminate redundant barrier intrinsics (PR #112023)

[David Sherwood via llvm-commits]

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@@ -0,0 +1,180 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -passes=instcombine < %s | FileCheck %s
+; ARM64 dmb intrinsics
+
+target triple = "aarch64-unknown-linux-gnu"
+
+declare void @llvm.aarch64.dmb(i32)
+declare void @clobber()
+declare void @pure() memory(none) willreturn nounwind
+
+define void @simple() #0 {
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david-arm wrote:

We should probably have a negative test for the case where the input arguments are different.

https://github.com/llvm/llvm-project/pull/112023