[clang] [Clang] Add AArch64 SME changes to the release notes (PR #122899)

[Sander de Smalen via cfe-commits]

https://github.com/sdesmalen-arm created https://github.com/llvm/llvm-project/pull/122899

None

>From e5c0686058f5dac17b02547e283df9bd20d24cae Mon Sep 17 00:00:00 2001
From: Sander de Smalen <sander.desmalen at arm.com>
Date: Tue, 14 Jan 2025 13:23:54 +0000
Subject: [PATCH] [Clang] Add AArch64 SME changes to the release notes

---
 clang/docs/ReleaseNotes.rst | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
index 794943b24a003c..4e473772329fae 100644
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -1076,6 +1076,15 @@ Arm and AArch64 Support
   in leaf functions after enabling ``-fno-omit-frame-pointer``, you can do so by adding
   the ``-momit-leaf-frame-pointer`` option.
 
+- SME keyword attributes which apply to function types are now represented in the
+  mangling of the type.  This means that ``void foo(void (*f)() __arm_streaming);``
+  now has a different mangling from ``void foo(void (*f)());``.
+
+- The ``__arm_agnostic`` keyword attribute was added to let users describe
+  a function that preserves SME state enabled by PSTATE.ZA without having to share
+  this state with its callers and without making the assumption that this state
+  exists.
+
 - Support has been added for the following processors (-mcpu identifiers in parenthesis):
 
   For AArch64: