Commit Graph

6 Commits

Author SHA1 Message Date
Craig Topper 12463779d3 [SimplifyCFG] When merging conditional stores, don't count the store we're merging against the PHINodeFoldingThreshold
Merging conditional stores tries to check to see if the code is if convertible after the store is moved. But the store hasn't been moved yet so its being counted against the threshold.

The patch adds 1 to the threshold comparison to make sure we don't count the store. I've adjusted a test to use a lower threshold to ensure we still do that conversion with the lower threshold.

Differential Revision: https://reviews.llvm.org/D39570

llvm-svn: 317368
2017-11-03 21:08:13 +00:00
Craig Topper 81d6d6b643 [SimplifyCFG] Regenerate some test cases using update_test_checks.py to prepare for an upcoming commit. NFC
A future commit will change how some of the value names in the IR are generated which causes these tests to break in their current form. The script generates checks with regular expressions so it should be immune.

llvm-svn: 317023
2017-10-31 19:03:49 +00:00
Evgeniy Stepanov e257f0f671 Tweak unnamed label syntax in textual IR for easier matching in tests.
Change the unnamed label comments like
  ; <label>:8  ; preds = %1
to
  ; <label>:8:  ; preds = %1

This way lit tests can match [[LABEL]]: in both asserts and no-asserts builds.

llvm-svn: 258993
2016-01-27 21:53:08 +00:00
James Molloy 3d21dcf3ed [SimplifyCFG] Don't create unnecessary PHIs
In conditional store merging, we were creating PHIs when we didn't
need to. If the value to be predicated isn't defined in the block
we're predicating, then it doesn't need a PHI at all (because we only
deal with triangles and diamonds, any value not in the predicated BB
must dominate the predicated BB).

This fixes a large code size increase in some benchmarks in a popular embedded benchmark suite.

Now with a fix (and fixed tests) for the conformance issue seen in Chromium.

llvm-svn: 255767
2015-12-16 14:12:44 +00:00
Reid Kleckner db9a91e324 Revert "Don't create unnecessary PHIs"
This reverts commit r255489.

It causes test failures in Chromium and does not appear to respect the
AlternativeV parameter.

llvm-svn: 255562
2015-12-14 22:36:57 +00:00
James Molloy 2b1e101e99 Don't create unnecessary PHIs
In conditional store merging, we were creating PHIs when we didn't
need to. If the value to be predicated isn't defined in the block
we're predicating, then it doesn't need a PHI at all (because we only
deal with triangles and diamonds, any value not in the predicated BB
must dominate the predicated BB).

This fixes a large code size increase in some benchmarks in a popular embedded benchmark suite.

llvm-svn: 255489
2015-12-14 10:57:01 +00:00