commit bc3948f0b9e92fb855de95af432a33cdd1bd490e
author rmcilroy@chromium.org <rmcilroy@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> Thu Apr 10 23:38:21 2014 +0900
committer Qijiang Fan <fqj@google.com> Thu Jun 04 16:27:09 2020 +0900
tree a3602e29c96fb1963553caf24d35e903cb3f4fbd
parent c93a461bec1b1fc3f955714e1485e8e4619533fb

Fix and improve arm64 atomic operations in Base.

 - The 'compare and swap' operations should enforce memory ordering even when
   the exchange does not occur.
 - The exclusive monitor does not need to be cleared by CLREX if a LDRX was
   not followed by a matching STREX.
 - Use LDAR and STLR where possible.
 - Use the 'I' and 'J' constraints to hint for constants valid for immediate
   values

Based on V8 changes at https://codereview.chromium.org/220793002

BUG=354405

Review URL: https://codereview.chromium.org/230963002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@262986 0039d316-1c4b-4281-b951-d872f2087c98


CrOS-Libchrome-Original-Commit: 9bfc380d97bd87df1d5b8d84695013b5621a4025