As it's causing some bot failures (and per request from kbarton).
This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@358546 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
MemorySSA is not properly updated in LoopSimplifyCFG after recent changes. Use SplitBlock utility to resolve that and clear all updates once handleDeadExits is finished.
All updates that follow are removal of edges which are safe to handle via the removeEdge() API.
Also, deleting dead blocks is done correctly as is, i.e. delete from MemorySSA before updating the CFG and DT.
Reviewers: mkazantsev, rtereshin
Subscribers: sanjoy, jlebar, Prazek, george.burgess.iv, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58524
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354613 91177308-0d34-0410-b5e6-96231b3b80d8
When we create fictive switch in preheader, we should take
care about MSSA and delete edge between old preheader and
header.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@354547 91177308-0d34-0410-b5e6-96231b3b80d8
Utility function that we use for blocks deletion always unconditionally removes
one-input Phis. In LoopSimplifyCFG, it can lead to breach of LCSSA form.
This patch alters this function to keep them if needed.
Differential Revision: https://reviews.llvm.org/D57231
Reviewed By: fedor.sergeev
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@353803 91177308-0d34-0410-b5e6-96231b3b80d8
During the transforms in LoopSimplifyCFG, when we remove a dead exiting edge, the
parent loop may stop being reachable from the child loop, and therefore they become
siblings. If the former child loop had uses of some values from its former parent loop,
now such uses will require LCSSA Phis, even if they weren't needed before. So we must
form LCSSA for all loops that stopped being ancestors of the current loop in this case.
Differential Revision: https://reviews.llvm.org/D56144
Reviewed By: fedor.sergeev
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@351434 91177308-0d34-0410-b5e6-96231b3b80d8
When removing edges, we also update Phi inputs and may end up removing
a Phi if it has only one input. We should not do it for edges that leave the current
loop because these Phis are LCSSA Phis and need to be preserved.
Thanks @dmgreen for finding this!
Differential Revision: https://reviews.llvm.org/D54841
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@347484 91177308-0d34-0410-b5e6-96231b3b80d8
