Commit Graph

4 Commits

Author SHA1 Message Date
Eric Christopher cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Markus Lavin 4dc4ebd606 [PM] Port LoadStoreVectorizer to the new pass manager.
Differential Revision: https://reviews.llvm.org/D54848

llvm-svn: 348570
2018-12-07 08:23:37 +00:00
Roman Tereshin 02320eee6b Revert "[SCEV][NFC] Check NoWrap flags before lexicographical comparison of SCEVs"
This reverts r319889.

Unfortunately, wrapping flags are not a part of SCEV's identity (they
do not participate in computing a hash value or in equality
comparisons) and in fact they could be assigned after the fact w/o
rebuilding a SCEV.

Grep for const_cast's to see quite a few of examples, apparently all
for AddRec's at the moment.

So, if 2 expressions get built in 2 slightly different ways: one with
flags set in the beginning, the other with the flags attached later
on, we may end up with 2 expressions which are exactly the same but
have their operands swapped in one of the commutative N-ary
expressions, and at least one of them will have "sorted by complexity"
invariant broken.

2 identical SCEV's won't compare equal by pointer comparison as they
are supposed to.

A real-world reproducer is added as a regression test: the issue
described causes 2 identical SCEV expressions to have different order
of operands and therefore compare not equal, which in its turn
prevents LoadStoreVectorizer from vectorizing a pair of consecutive
loads.

On a larger example (the source of the test attached, which is a
bugpoint) I have seen even weirder behavior: adding a constant to an
existing SCEV changes the order of the existing terms, for instance,
getAddExpr(1, ((A * B) + (C * D))) returns (1 + (C * D) + (A * B)).

Differential Revision: https://reviews.llvm.org/D40645

llvm-svn: 340777
2018-08-27 21:41:37 +00:00