Merge pull request dotnet/coreclr#18287 from sdmaclea/TryClearGCStressInstructionUpdate
authorBruce Forstall <brucefo@microsoft.com>
Fri, 8 Jun 2018 21:27:18 +0000 (14:27 -0700)
committerGitHub <noreply@github.com>
Fri, 8 Jun 2018 21:27:18 +0000 (14:27 -0700)
Use atomic ops in CommitGCStressInstructionUpdate()

Commit migrated from https://github.com/dotnet/coreclr/commit/22b18c598e93d85d012ac2d39f248acd09fec941


Trivial merge