diff --git a/clang/docs/ReleaseNotes.rst b/clang/docs/ReleaseNotes.rst
--- a/clang/docs/ReleaseNotes.rst
+++ b/clang/docs/ReleaseNotes.rst
@@ -83,6 +83,12 @@
   - RISC-V SiFive S54 (``sifive-s54``).
   - RISC-V SiFive S76 (``sifive-s76``).
 
+- Support has been added for the following architectures (``-march`` identifiers in parentheses):
+
+  - Armv9-A (``armv9-a``).
+  - Armv9.1-A (``armv9.1-a``).
+  - Armv9.2-A (``armv9.2-a``).
+
 Removed Compiler Flags
 -------------------------
 
diff --git a/llvm/docs/ReleaseNotes.rst b/llvm/docs/ReleaseNotes.rst
--- a/llvm/docs/ReleaseNotes.rst
+++ b/llvm/docs/ReleaseNotes.rst
@@ -73,12 +73,12 @@
 Changes to the AArch64 Backend
 ------------------------------
 
-* ...
+* Added support for the Armv9-A, Armv9.1-A and Armv9.2-A architectures.
 
 Changes to the ARM Backend
 --------------------------
 
-During this release ...
+* Added support for the Armv9-A, Armv9.1-A and Armv9.2-A architectures.
 
 Changes to the MIPS Target
 --------------------------