commit 7747c1d2df876168611373f39f8513701f77e777
author Philip Reames <listmail@philipreames.com> Thu Mar 14 17:20:59 2019 +0000
committer Philip Reames <listmail@philipreames.com> Thu Mar 14 17:20:59 2019 +0000
tree be0a047e6d9fa6c1da977dd8efd77aa4f40038f4
parent 3b4378582808382fd4abfb57b51ec6e2ce77ee4c

Allow code motion (and thus folding) for atomic (but unordered) memory operands

Building on the work done in D57601, now that we can distinguish between atomic and volatile memory accesses, go ahead and allow code motion of unordered atomics. As seen in the diffs, this allows much better folding of memory operations into using instructions. (Mostly done by the PeepholeOpt pass.)

Note: I have not reviewed all callers of hasOrderedMemoryRef since one of them - isSafeToMove - is very widely used. I'm relying on the documented semantics of each method to judge correctness.

Differential Revision: https://reviews.llvm.org/D59345



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@356170 91177308-0d34-0410-b5e6-96231b3b80d8