As LoopPredication performs non-equivalent transforms removing some
checks from loops, other passes may not be able to perform transforms
they'd be able to do if the checks were left in loops.
This patch makes LoopPredication insert assumes of the replaced
conditions either after a guard call or in the true block of
widenable condition branch.
Differential Revision: https://reviews.llvm.org/D135354
Upon further investigation and discussion,
this is actually the opposite direction from what we should be taking,
and this direction wouldn't solve the motivational problem anyway.
Additionally, some more (polly) tests have escaped being updated.
So, let's just take a step back here.
This reverts commit f3190dedeef9da2109ea57e4cb372f295ff53b88.
This reverts commit 749581d21f2b3f53e4fca4eb8728c942d646893b.
This reverts commit f3df87d57e096143670e0fd396e81d43393a2dd2.
This reverts commit ab1dbcecd6f0969976fafd62af34730436ad5944.
Since LICM has now unconditionally moved to MemorySSA based form, all
passes that run in same LPM as LICM need to preserve MemorySSA (i.e. our
downstream pipeline).
Added loop-mssa to all tests and perform -verify-memoryssa within
LoopPredication itself.
Differential Revision: https://reviews.llvm.org/D108724
As it's causing some bot failures (and per request from kbarton).
This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.
llvm-svn: 358546
LoopPredication was replacing the original condition, but leaving the instructions to compute the old conditions around. This would get cleaned up by other passes of course, but we might as well do it eagerly. That also makes the test output less confusing.
llvm-svn: 357406
I'm about to make some changes to the pass which cause widespread - but uninteresting - test diffs. Prepare the tests for easy updating.
llvm-svn: 357404
Add support of uge and sge latch condition to Loop Prediction for
reverse loops.
Reviewers: apilipenko, mkazantsev, sanjoy, anna
Reviewed By: anna
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D42837
llvm-svn: 324589
Summary:
Currently, we only support predication for forward loops with step
of 1. This patch enables loop predication for reverse or
countdownLoops, which satisfy the following conditions:
1. The step of the IV is -1.
2. The loop has a singe latch as B(X) = X <pred>
latchLimit with pred as s> or u>
3. The IV of the guard is the decrement
IV of the latch condition (Guard is: G(X) = X-1 u< guardLimit).
This patch was downstream for a while and is the last series of patches
that's from our LP implementation downstream.
Reviewers: apilipenko, mkazantsev, sanjoy
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D40353
llvm-svn: 319659
