[InstCombine] Always treat inner and/or as bitwise (#121766)

In https://github.com/llvm/llvm-project/pull/116065, we pass `IsLogical`
into `foldBooleanAndOr` when folding inner and/or ops. But it i

[InstCombine] Always treat inner and/or as bitwise (#121766)

In https://github.com/llvm/llvm-project/pull/116065, we pass `IsLogical`
into `foldBooleanAndOr` when folding inner and/or ops. But it is always
safe to treat them as bitwise if the outer ops are bitwise.

Alive2: https://alive2.llvm.org/ce/z/hULrgH
Closes https://github.com/llvm/llvm-project/issues/121701.

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[LLVM][IR] Use splat syntax when printing Constant[Data]Vector. (#112548)

[InstCombine] Remove AllOnes fallbacks in getMaskedTypeForICmpPair() (#104941)

getMaskedTypeForICmpPair() tries to model non-and operands as x & -1.
However, this can end up confusing the matching

[InstCombine] Remove AllOnes fallbacks in getMaskedTypeForICmpPair() (#104941)

getMaskedTypeForICmpPair() tries to model non-and operands as x & -1.
However, this can end up confusing the matching logic, by picking the -1
operand as the "common" operand, resulting in a successful, but useless,
match. This is what causes commutation failures for some of the
optimizations driven by this function.

Fix this by treating a match against -1 as a non-match.

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[InstCombine] Handle logical op for and/or of icmp 0/-1

This aligns the transform with what foldLogOpOfMaskedICmp() does.

[InstCombine] Add more test variants with poison elements (NFC)

[InstCombine] Add more tests for foldLogOpOfMaskedICmps transform (NFC)

Tests for cases that would have been regressed by
https://github.com/llvm/llvm-project/pull/104941.

[InstCombine] Remove some of the complexity-based canonicalization (#91185)

The idea behind this canonicalization is that it allows us to handle less
patterns, because we know that some will be can

[InstCombine] Remove some of the complexity-based canonicalization (#91185)

The idea behind this canonicalization is that it allows us to handle less
patterns, because we know that some will be canonicalized away. This is
indeed very useful to e.g. know that constants are always on the right.

However, this is only useful if the canonicalization is actually
reliable. This is the case for constants, but not for arguments: Moving
these to the right makes it look like the "more complex" expression is
guaranteed to be on the left, but this is not actually the case in
practice. It fails as soon as you replace the argument with another
instruction.

The end result is that it looks like things correctly work in tests,
while they actually don't. We use the "thwart complexity-based
canonicalization" trick to handle this in tests, but it's often a
challenge for new contributors to get this right, and based on the
regressions this PR originally exposed, we clearly don't get this right
in many cases.

For this reason, I think that it's better to remove this complexity
canonicalization. It will make it much easier to write tests for
commuted cases and make sure that they are handled.

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[InstCombine] Thwart complexity-based canonicalization in test (NFC)

[NFC] Regenerate test file InstCombine/bit-checks.ll

[test] Use -passes=instcombine instead of -instcombine in lots of tests. NFC

Another step moving away from the deprecated syntax of specifying
pass pipeline in opt.

Differential Revision: https://r

[test] Use -passes=instcombine instead of -instcombine in lots of tests. NFC

Another step moving away from the deprecated syntax of specifying
pass pipeline in opt.

Differential Revision: https://reviews.llvm.org/D119081

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[InstCombine] allow matching vector splat constants in foldLogOpOfMaskedICmps()

This is NFC-intended for scalar code. There are still unnecessary
m_ConstantInt restrictions in surrounding code, so t

[InstCombine] allow matching vector splat constants in foldLogOpOfMaskedICmps()

This is NFC-intended for scalar code. There are still unnecessary
m_ConstantInt restrictions in surrounding code, so this is not a
complete fix.

This prevents regressions seen with a planned follow-on to D111410.

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[InstCombine] add vector splat tests for foldLogOpOfMaskedICmps(); NFC

There's a substantial pile of scalar tests for transforms that
depend on this code, but zero vector coverage. This patch adds
a

[InstCombine] add vector splat tests for foldLogOpOfMaskedICmps(); NFC

There's a substantial pile of scalar tests for transforms that
depend on this code, but zero vector coverage. This patch adds
a vector test next to the first scalar test in each file that
is affected by foldLogOpOfMaskedICmps.

The code that handles these transforms is artificially limited
from working with vector splat constants.

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[InstCombine] Fully disable select to and/or i1 folding

This is a patch that disables the poison-unsafe select -> and/or i1 folding.

It has been blocking D72396 and also has been the source of a fe

[InstCombine] Fully disable select to and/or i1 folding

This is a patch that disables the poison-unsafe select -> and/or i1 folding.

It has been blocking D72396 and also has been the source of a few miscompilations
described in llvm.org/pr49688 .
D99674 conditionally blocked this folding and successfully fixed the latter one.
The former one was still blocked, and this patch addresses it.

Note that a few test functions that has `_logical` suffix are now deoptimized.
These are created by @nikic to check the impact of disabling this optimization
by copying existing original functions and replacing and/or with select.

I can see that most of these are poison-unsafe; they can be revived by introducing
freeze instruction. I left comments at fcmp + select optimizations (or-fcmp.ll, and-fcmp.ll)
because I think they are good targets for freeze fix.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D101191

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[InstCombine] Duplicate tests for logical and/or (NFC)

This replicates existing and/or tests to also test variants using
select. This should help us get a more accurate view on which
optimizations w

[InstCombine] Duplicate tests for logical and/or (NFC)

This replicates existing and/or tests to also test variants using
select. This should help us get a more accurate view on which
optimizations we're missing if we disable the select -> and/or
fold.

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Revert "Temporarily Revert "Add basic loop fusion pass.""

The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552

[InstCombine][InstSimplify] Teach decomposeBitTestICmp to look through truncate instructions

This patch teaches decomposeBitTestICmp to look through truncate instructions on the input to the compare

[InstCombine][InstSimplify] Teach decomposeBitTestICmp to look through truncate instructions

This patch teaches decomposeBitTestICmp to look through truncate instructions on the input to the compare. If a truncate is found it will now return the pre-truncated Value and appropriately extend the APInt mask.

This allows some code to be removed from InstSimplify that was doing this functionality.

This allows InstCombine's bit test combining code to match a pre-truncate Value with the same Value appear with an 'and' on another icmp. Or it allows us to combine a truncate to i16 and a truncate to i8. This also required removing the type check from the beginning of getMaskedTypeForICmpPair, but I believe that's ok because we still have to find two values from the input to each icmp that are equal before we'll do any transformation. So the type check was really just serving as an early out.

There was one user of decomposeBitTestICmp that didn't want to look through truncates, so I've added a flag to prevent that behavior when necessary.

Differential Revision: https://reviews.llvm.org/D37158

llvm-svn: 312382

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[InstCombine] Add tests to show missed opportunities to combine bit tests hidden by a sign compare and a truncate. NFC

llvm-svn: 311784

[InstCombine] update to use FileCheck

Also, remove unnecessary function attributes, parameters, and comments.
It looks like at least some of these tests are not minimal though...

llvm-svn: 282620

Fix the remaining TCL-style quotes found in the testsuite. This is
another mechanical change accomplished though the power of terrible Perl
scripts.

I have manually switched some "s to 's to make es

Fix the remaining TCL-style quotes found in the testsuite. This is
another mechanical change accomplished though the power of terrible Perl
scripts.

I have manually switched some "s to 's to make escaping simpler.

While I started this to fix tests that aren't run in all configurations,
the massive number of tests is due to a really frustrating fragility of
our testing infrastructure: things like 'grep -v', 'not grep', and
'expected failures' can mask broken tests all too easily.

Essentially, I'm deeply disturbed that I can change the testsuite so
radically without causing any change in results for most platforms. =/

llvm-svn: 159547

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Generalize instcombine's support for combining multiple bit checks into a single test. Patch by Dirk Steinke!

llvm-svn: 113423

Re-apply the infamous r108614, with a fix pointed out by Dirk Steinke.

llvm-svn: 110036

Another attempt at getting the clang self-host to like my instcombine patch.

llvm-svn: 108614

Reapply r108378, with bugfixes, testcase, and improved comment formatting.
This now passes LIT, nighty test, and llvm-gcc bootstrap on my machine.

llvm-svn: 108422