[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
+
+declare void @llvm.aarch64.stshh(i64)
+
+define void @test_stshh_atomic_store(ptr %p, i32 %v) {
+; CHECK-LABEL: test_stshh_atomic_store
+; CHECK: stshh
+; CHECK: str
+  call void @llvm.aarch64.stshh(i64 0)
+  store atomic i32 %v, ptr %p monotonic, align 4
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kmclaughlin-arm wrote:

If this test is only being added for the intrinsic, can the store be removed?

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