[clang] [llvm] [AArch64] Implement the atomic fetch with hint intrinsic (PR #227711)

[Kerry McLaughlin via cfe-commits]

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@@ -0,0 +1,241 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=aarch64-none-linux-gnu -mattr=+lse -verify-machineinstrs < %s | FileCheck %s --check-prefixes=CHECK
+; RUN: llc -mtriple=aarch64-none-linux-gnu -mattr=+lse -global-isel=1 -global-isel-abort=0 -verify-machineinstrs < %s | FileCheck %s --check-prefixes=CHECK
----------------
kmclaughlin-arm wrote:

nit:

```suggestion
; RUN: llc -mtriple=aarch64-none-linux-gnu -mattr=+lse -verify-machineinstrs < %s | FileCheck %s
; RUN: llc -mtriple=aarch64-none-linux-gnu -mattr=+lse -global-isel=1 -global-isel-abort=0 -verify-machineinstrs < %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/227711