[llvm] [Mips] Use AtomicExpandPass for subword atomics (PR #225948)

[Jessica Clarke via llvm-commits]

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@@ -0,0 +1,362 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc -mtriple=mips64el -target-abi=n32 -mcpu=mips64r2 -verify-machineinstrs < %s | FileCheck %s --check-prefix=LE
+; RUN: llc -mtriple=mips64 -target-abi=n32 -mcpu=mips64r2 -verify-machineinstrs < %s | FileCheck %s --check-prefix=BE
+; RUN: llc -mtriple=mips64el -target-abi=n32 -mcpu=mips64r6 -O0 -verify-machineinstrs < %s | FileCheck %s --check-prefix=LE-R6
+; RUN: llc -mtriple=mips64 -target-abi=n32 -mcpu=mips64r6 -O0 -verify-machineinstrs < %s | FileCheck %s --check-prefix=BE-R6
+
+; N32 masked atomics use 32-bit addresses and aligned i32 memory accesses.
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jrtc27 wrote:

Please use ;; throughout for comments that aren't for lit/FileCheck

https://github.com/llvm/llvm-project/pull/225948