Merge pull request dotnet/coreclr#18941 from CarolEidt/Fix18884
authorCarol Eidt <carol.eidt@microsoft.com>
Wed, 18 Jul 2018 18:01:46 +0000 (11:01 -0700)
committerGitHub <noreply@github.com>
Wed, 18 Jul 2018 18:01:46 +0000 (11:01 -0700)
Kill RCX when used by shift

Commit migrated from https://github.com/dotnet/coreclr/commit/394341afe705377db0c194cee2bd0ad9bd22585b


Trivial merge