More x86 release notes.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_50@310501 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index 384b101c34ac00f28d4f15e399a9d8f1927c890e..cfb9cc0815cb78330aaf991d57bc6a1e9929924b 100644 (file)
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -117,6 +117,18 @@ Changes to the X86 Target
 
 * Added support for AMD Lightweight Profiling (LWP) instructions.
 
+* Avoid using slow LEA instructions.
+
+* Use alternative sequences for multiply by constant.
+
+* Improved lowering of strided shuffles.
+
+* Improved the AVX512 cost model used by the vectorizer.
+
+* Fix scalar code performance when AVX512 is enabled by making i1's illegal.
+
+* Fixed many inline assembly bugs.
+
 Changes to the AMDGPU Target
 -----------------------------