[clang] [libcxx] [Clang] Support atomic operations on _BitInt(N) (PR #204815)

[Xavier Roche via cfe-commits]

================
@@ -0,0 +1,91 @@
+// RUN: %clang_cc1 -std=c23 -triple x86_64-unknown-linux-gnu -emit-llvm %s -o - | FileCheck %s
----------------
xroche wrote:

Regenerated with utils/update_cc_test_checks.py in ece5743. The lowering is now visible: the compare-exchange loop, the width-N arithmetic, and the sext/zext canonicalization.

https://github.com/llvm/llvm-project/pull/204815