Update README.md and CHANGELOG.md for LLVM-19 release (#507)

* Incorporate changes made for LLVM-18 release.
* Add additional supported targets to README.md.
* Remove experimental from AArch64.
* Update CHANGELOG for changes made since LLVM-18.

Author: smithp35

CHANGELOG.md

@@ -6,8 +6,26 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ## [Unreleased]
 
+## [19.0.0]
+
+### Added
+- AArch32 v8-A and v8-R can now be targeted (#484) (#486).
+- Experimental support for building llvm-libc overlay package (#452).
+- Additional library variants for Armv7 (#464) (#491) (#494).
+- Additional multilib mappings for v7ve and Thumb target triples (#479) (#481).
+- Omax and OmaxLTO config files (#454).
+
 ### Changed
 - Use unstable libc++ ABI (#294).
+- Merge v7-M and v7E-M library variants (#482).
+- AArch64 A-profile library made distinct (#468).
+
+## [18.0.0]
+
+### Added
+
+- Documentation for the newlib overlay package (#399).
+- Support for C++ exceptions and RTTI added in the standard libraries (#339).
 
 ## [17.0.0]
 

README.md

@@ -26,7 +26,11 @@ embedded and realtime operating systems.
 - Armv4T (experimental)
 - Armv5TE (experimental)
 - Armv6 (experimental, using the Armv5TE library variant)
-- AArch64 armv8.0 (experimental)
+- Armv7-A
+- Armv7-R
+- AArch32 Armv8-A
+- AArch32 Armv8-R
+- AArch64 Armv8-A
 
 ## C++ support