[DependenceAnalysis] Dependecies for loads marked with "ivnariant.load" should…

Authored by ebrevnov on Jan 16 2020, 12:17 AM.


[DependenceAnalysis] Dependecies for loads marked with "ivnariant.load" should not be shared with general accesses(PR42151).

This is second attempt to fix the problem with incorrect dependencies reported in presence of invariant load. Initial fix (https://reviews.llvm.org/D64405) was reverted due to a regression reported in https://reviews.llvm.org/D70516.

The original fix changed caching behavior for invariant loads. Namely such loads are not put into the second level cache (NonLocalDepInfo). The problem with that fix is the first level cache (CachedNonLocalPointerInfo) still works as if invariant loads were in the second level cache. The solution is in addition to not putting dependence results into the second level cache avoid putting info about invariant loads into the first level cache as well.

Reviewers: jdoerfert, reames, hfinkel, efriedma

Reviewed By: jdoerfert

Subscribers: DaniilSuchkov, hiraditya, bmahjour, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D73027