Commit Graph

6 Commits

Author SHA1 Message Date
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
Eli Friedman 4532a50899 Infer alignment of unmarked loads in IR/bitcode parsing.
For IR generated by a compiler, this is really simple: you just take the
datalayout from the beginning of the file, and apply it to all the IR
later in the file. For optimization testcases that don't care about the
datalayout, this is also really simple: we just use the default
datalayout.

The complexity here comes from the fact that some LLVM tools allow
overriding the datalayout: some tools have an explicit flag for this,
some tools will infer a datalayout based on the code generation target.
Supporting this properly required plumbing through a bunch of new
machinery: we want to allow overriding the datalayout after the
datalayout is parsed from the file, but before we use any information
from it. Therefore, IR/bitcode parsing now has a callback to allow tools
to compute the datalayout at the appropriate time.

Not sure if I covered all the LLVM tools that want to use the callback.
(clang? lli? Misc IR manipulation tools like llvm-link?). But this is at
least enough for all the LLVM regression tests, and IR without a
datalayout is not something frontends should generate.

This change had some sort of weird effects for certain CodeGen
regression tests: if the datalayout is overridden with a datalayout with
a different program or stack address space, we now parse IR based on the
overridden datalayout, instead of the one written in the file (or the
default one, if none is specified). This broke a few AVR tests, and one
AMDGPU test.

Outside the CodeGen tests I mentioned, the test changes are all just
fixing CHECK lines and moving around datalayout lines in weird places.

Differential Revision: https://reviews.llvm.org/D78403
2020-05-14 13:03:50 -07:00
Roman Tereshin 1ba1f9310c [SCEV] Add zext(C + x + ...) -> D + zext(C-D + x + ...)<nuw><nsw> transform
if the top level addition in (D + (C-D + x + ...)) could be proven to
not wrap, where the choice of D also maximizes the number of trailing
zeroes of (C-D + x + ...), ensuring homogeneous behaviour of the
transformation and better canonicalization of such expressions.

This enables better canonicalization of expressions like

  1 + zext(5 + 20 * %x + 24 * %y)  and
      zext(6 + 20 * %x + 24 * %y)

which get both transformed to

  2 + zext(4 + 20 * %x + 24 * %y)

This pattern is common in address arithmetics and the transformation
makes it easier for passes like LoadStoreVectorizer to prove that 2 or
more memory accesses are consecutive and optimize (vectorize) them.

Reviewed By: mzolotukhin

Differential Revision: https://reviews.llvm.org/D48853

llvm-svn: 337859
2018-07-24 21:48:56 +00:00
Sanjoy Das eeca9f6fd4 [SCEV] Commute zero extends through <nuw> additions
llvm-svn: 251052
2015-10-22 19:57:38 +00:00
Sanjoy Das a060e602fd [SCEV] Commute sign extends through nsw additions
Summary: Depends on D13613.

Reviewers: atrick, hfinkel, reames, nlewycky

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13685

llvm-svn: 251049
2015-10-22 19:57:25 +00:00
Sanjoy Das 8f27415c05 [SCEV] Mark AddExprs as nsw or nuw if legal
Summary:
This uses `ScalarEvolution::getRange` and not potentially control
dependent `nsw` and `nuw` bits on the arithmetic instruction.

Reviewers: atrick, hfinkel, nlewycky

Subscribers: llvm-commits, sanjoy

Differential Revision: http://reviews.llvm.org/D13613

llvm-svn: 251048
2015-10-22 19:57:19 +00:00