[clang] [llvm] [AArch64][clang][llvm] Add ACLE `stshh` atomic store builtin (PR #181386)

[Kerry McLaughlin via llvm-commits]

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@@ -0,0 +1,12 @@
+; RUN: llc -mtriple=aarch64 -mattr=+pcdphint < %s | FileCheck %s
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kmclaughlin-arm wrote:

Can `-mattr=+pcdphint` be removed now?

https://github.com/llvm/llvm-project/pull/181386