Change all the cstval_pred_ty based PatternMatch helpers (things like
m_AllOnes and m_Zero) to only allow poison elements inside vector
splats, not undef elements.
Historically, we used to represent non-demanded elements in vectors
using undef. Nowadays, we use poison instead. As such, I believe that
support for undef in vector splats is no longer useful.
At the same time, while poison splat elements are pretty much always
safe to ignore, this is not generally the case for undef elements. We
have existing miscompiles in our tests due to this (see the
masked-merge-*.ll tests changed here) and it's easy to miss such cases
in the future, now that we write tests using poison instead of undef
elements.
I think overall, keeping support for undef elements no longer makes
sense, and we should drop it. Once this is done consistently, I think we
may also consider allowing poison in m_APInt by default, as doing that
change is much less risky than doing the same with undef.
This change involves a substantial amount of test changes. For most
tests, I've just replaced undef with poison, as I don't think there is
value in retaining both. For some tests (where the distinction between
undef and poison is important), I've duplicated tests.
Another step towards getting rid of dependencies to the legacy
pass manager.
Primary change here is to just do -passes=foo instead of -foo in
simple situations (when running a single transform pass). But also
updated a few test running multiple passes.
Also removed some "duplicated" RUN lines in a few tests that where
using both -foo and -passes=foo syntax. No need to do the same kind
of testing twice.
As shown in the examples in issue #57683, we allow matching
vectors with poison (undef) in this transform (and possibly more),
but we can't then use the partially defined value as a replacement
value in other expressions blindly.
This seems to be avoided in simpler examples of reassociation,
and other passes should be able to clean up the redundant op
seen in these tests.
As it's causing some bot failures (and per request from kbarton).
This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.
llvm-svn: 358546
We need to update this code before introducing an 'fneg' instruction in IR,
so we might as well kill off the integer neg/not queries too.
This is no-functional-change-intended for scalar code and most vector code.
For vectors, we can see that the 'match' API allows for undef elements in
constants, so we optimize those cases better.
Ideally, there would be a test for each code diff, but I don't see evidence
of that for the existing code, so I didn't try very hard to come up with new
vector tests for each code change.
Differential Revision: https://reviews.llvm.org/D53533
llvm-svn: 345042
I was trying to provide test coverage for D53533
with rL344964, but these don't do it...and I don't
think they add any value, so deleting.
llvm-svn: 344969
Also, regenerate checks for these files. We should do better
on the vector tests by using the PatternMatch API instead of
BinaryOperator::isNot/isNeg.
llvm-svn: 344964
input filename so that opt doesn't print the input filename in the
output so that grep lines in the tests don't unintentionally match
strings in the input filename.
llvm-svn: 81537
