Mention ThinLTO in ReleaseNotes

https://reviews.llvm.org/D28746

git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_40@292079 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/ReleaseNotes.rst b/docs/ReleaseNotes.rst
index b92527dbb2969fc34298c1684a5dbb0983c75327..dcb742e18c638d3e8168c723177bd402e04ecf4a 100644 (file)
--- a/docs/ReleaseNotes.rst
+++ b/docs/ReleaseNotes.rst
@@ -67,6 +67,14 @@ Non-comprehensive list of changes in this release
 
    Makes programs 10x faster by doing Special New Thing.
 
+   Improvements to ThinLTO (-flto=thin)
+   ------------------------------------
+   * Integration with profile data (PGO). When available, profile data 
+     enables more accurate function importing decisions, as well as 
+     cross-module indirect call promotion.
+   * Significant build-time and binary-size improvements when compiling with 
+     debug info (-g).
+
 Changes to the LLVM IR
 ----------------------