Commit Graph

5 Commits

Author SHA1 Message Date
Nikita Popov 0dda633317 [SCEV] Strength nowrap flags after constant folding
We should first try to constant fold the add expression and only
strengthen nowrap flags afterwards. This allows us to determine
stronger flags if e.g. only two operands are left after constant
folding (and thus "guaranteed no wrap region" code applies) or the
resulting operands are non-negative and thus nsw->nuw strengthening
applies.
2020-10-25 18:00:22 +01:00
Arthur Eubanks 9adbb5cb3a [SCEV] Fix ScalarEvolution tests under NPM
Many tests use opt's -analyze feature, which does not translate well to
NPM and has better alternatives. The alternative here is to explicitly
add a pass that calls ScalarEvolution::print().

The legacy pass manager RUNs aren't changing, but they are now pinned to
the legacy pass manager.  For each legacy pass manager RUN, I added a
corresponding NPM RUN using the 'print<scalar-evolution>' pass. For
compatibility with update_analyze_test_checks.py and existing test
CHECKs, 'print<scalar-evolution>' now prints what -analyze prints per
function.

This was generated by the following Python script and failures were
manually fixed up:

import sys
for i in sys.argv:
    with open(i, 'r') as f:
        s = f.read()
    with open(i, 'w') as f:
        for l in s.splitlines():
            if "RUN:" in l and ' -analyze ' in l and '\\' not in l:
                f.write(l.replace(' -analyze ', ' -analyze -enable-new-pm=0 '))
                f.write('\n')
                f.write(l.replace(' -analyze ', ' -disable-output ').replace(' -scalar-evolution ', ' "-passes=print<scalar-evolution>" ').replace(" | ", " 2>&1 | "))
                f.write('\n')
            else:
                f.write(l)

There are a couple failures still in ScalarEvolution under NPM, but
those are due to other unrelated naming conflicts.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D83798
2020-07-16 11:24:07 -07:00
Philip Reames bdf608477e [SCEV] Add smin support to getRangeRef
We were failing to compute trip counts (both exact and maximum) for any loop which involved a comparison against either an umin or smin. It looks like this simply got missed when we added smin/umin to SCEV.  (Note: umin was submitted separately earlier today.  Turned out two folks hit this at the same time.)

Differential Revision: https://reviews.llvm.org/D67514

llvm-svn: 371776
2019-09-12 21:32:27 +00:00
Florian Hahn a31ee37624 [SCEV] Support SCEVUMinExpr in getRangeRef.
This patch adds support for SCEVUMinExpr to getRangeRef,
similar to the support for SCEVUMaxExpr.

Reviewers: sanjoy.google, efriedma, reames, nikic

Reviewed By: sanjoy.google

Differential Revision: https://reviews.llvm.org/D67177

llvm-svn: 371768
2019-09-12 20:03:32 +00:00
Philip Reames a3d2737520 Precommit tests for D67514
llvm-svn: 371762
2019-09-12 19:34:27 +00:00