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

[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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[PatternMatch] Do not accept undef elements in m_AllOnes() and friends (#88217)

Change all the cstval_pred_ty based PatternMatch helpers (things like
m_AllOnes and m_Zero) to only allow poison elem

[PatternMatch] Do not accept undef elements in m_AllOnes() and friends (#88217)

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.

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[InstCombine] Fix for folding `select` into floating point binary operators. (#83200)

Folding a `select` into a floating point binary operators can only be
done if the result is preserved for both

[InstCombine] Fix for folding `select` into floating point binary operators. (#83200)

Folding a `select` into a floating point binary operators can only be
done if the result is preserved for both case. In particular, if the
other operand of the `select` can be a NaN, then the transformation
won't preserve the result value.

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[InstCombine] Fold umax(smax)/smin(umin) with non-negative constants (#82929)

This patch extends `reassociateMinMaxWithConstants` to fold the
following patterns:
```
umax (smax X, nneg C0), nneg

[InstCombine] Fold umax(smax)/smin(umin) with non-negative constants (#82929)

This patch extends `reassociateMinMaxWithConstants` to fold the
following patterns:
```
umax (smax X, nneg C0), nneg C1 --> smax X, (umax C0, C1)
smin (umin X, nneg C0), nneg C1 --> umin X, (smin/umin C0, C1)
```
Alive2: https://alive2.llvm.org/ce/z/wfEj-e

Address the comment
https://github.com/llvm/llvm-project/pull/82472#pullrequestreview-1896922897.

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[InstCombine] Infer nneg on zext when forming from non-negative sext (#70706)

Builds on #67982 which recently introduced the nneg flag on a zext
instruction. InstCombine is one of our largest canon

[InstCombine] Infer nneg on zext when forming from non-negative sext (#70706)

Builds on #67982 which recently introduced the nneg flag on a zext
instruction. InstCombine is one of our largest canonicalizers of zext
from non-negative sext instructions, so set the flag there.

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[InstCombine] Preserve metadata when combining select+binop

Fixes https://github.com/llvm/llvm-project/issues/63910

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D155461

[InstCombine][NFC] Add tests for preserving metadata

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D155594

[InstCombine] Regenerate all test checks (NFC)

Due to an improvement to name preservation, a lot of InstCombine
tests now show spurious diffs when regenerated.

Rather than regenerating individual f

[InstCombine] Regenerate all test checks (NFC)

Due to an improvement to name preservation, a lot of InstCombine
tests now show spurious diffs when regenerated.

Rather than regenerating individual files when they get touched,
mass-regenerate all UTC-based InstCombine tests. I have then reset
a number of files showing suspicious diffs where the UTC output
has clearly been manually adjusted. I apologize if I missed
anything in the mass of changes.

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[test][InstCombine] Update some test cases to use opaque pointers

These tests cases were converted using the script at
https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34

Differential Re

[test][InstCombine] Update some test cases to use opaque pointers

These tests cases were converted using the script at
https://gist.github.com/nikic/98357b71fd67756b0f064c9517b62a34

Differential Revision: https://reviews.llvm.org/D135094

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[InstCombine] Canonicalize SPF to min/max intrinsics

Now that integer min/max intrinsics have good support in both
InstCombine and other passes, start canonicalizing SPF min/max
to intrinsic min/max

[InstCombine] Canonicalize SPF to min/max intrinsics

Now that integer min/max intrinsics have good support in both
InstCombine and other passes, start canonicalizing SPF min/max
to intrinsic min/max.

Once this sticks, we can stop matching SPF min/max in various
places, and can remove hacks we have for preventing infinite loops
and breaking of SPF canonicalization.

Differential Revision: https://reviews.llvm.org/D98152

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[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] canonicalizeAbsNabs(): don't propagate NSW flag for NABS patter

As Nuno is noting in post-commit review in
https://reviews.llvm.org/D87188#2467915
it is not correct to keep NSW for neg

[InstCombine] canonicalizeAbsNabs(): don't propagate NSW flag for NABS patter

As Nuno is noting in post-commit review in
https://reviews.llvm.org/D87188#2467915
it is not correct to keep NSW for negated abs pattern,
so don't do that.

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[NFC][InstCombine] Fixup check lines for prof md in select_meta.ll test

[InstCombine] Canonicalize SPF to abs intrinsic

This patch enables canonicalization of SPF_ABS and SPF_ABS
to the abs intrinsic.

This is a recommit, the original try was
05d4c4ebc2fb006b8a2bd05b24c

[InstCombine] Canonicalize SPF to abs intrinsic

This patch enables canonicalization of SPF_ABS and SPF_ABS
to the abs intrinsic.

This is a recommit, the original try was
05d4c4ebc2fb006b8a2bd05b24c6aba10dd2eef8,
but it was reverted due to an apparent miscompile,
which since then has just been fixed by the previous commit.

Differential Revision: https://reviews.llvm.org/D87188

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Revert "[InstCombine] Canonicalize SPF_ABS to abs intrinc"

This reverts commit 05d4c4ebc2fb006b8a2bd05b24c6aba10dd2eef8.

mstorsjo reports a miscompile after this change in
https://reviews.llvm.org/

Revert "[InstCombine] Canonicalize SPF_ABS to abs intrinc"

This reverts commit 05d4c4ebc2fb006b8a2bd05b24c6aba10dd2eef8.

mstorsjo reports a miscompile after this change in
https://reviews.llvm.org/D87188#2281093. Reverting until I can
investigate this.

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[InstCombine] Canonicalize SPF_ABS to abs intrinc

Enable canonicalization of SPF_ABS and SPF_NABS to the abs intrinsic.

To be conservative, the one-use check on the comparison is retained,
this may

[InstCombine] Canonicalize SPF_ABS to abs intrinc

Enable canonicalization of SPF_ABS and SPF_NABS to the abs intrinsic.

To be conservative, the one-use check on the comparison is retained,
this may be relaxed if all goes well.

It's pretty likely that this will uncover places that missing
handling for the abs() intrinsic. Please report any seen performance
regressions.

Differential Revision: https://reviews.llvm.org/D87188

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Revert "[InstCombine] do not exclude min/max from icmp with casted operand fold"

This reverts commit f2fbdf76d8d07f6a0fbd97825cbc533660d64a37.
As noted in the post-commit thread:
https://reviews.llv

Revert "[InstCombine] do not exclude min/max from icmp with casted operand fold"

This reverts commit f2fbdf76d8d07f6a0fbd97825cbc533660d64a37.
As noted in the post-commit thread:
https://reviews.llvm.org/rGf2fbdf76d8d0
...this can obscure a min/max pattern where the components
have extra uses. We can show that the problem is independent
of this change with a slightly modified source example, so
this revert just delays/reduces the need to fix the real
problem.

We need to improve our analysis of negation or -- more
generally -- subtraction using patches like D77230 or D68408.

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[InstCombine] remove stray auto-generated test comment; NFC

The script now includes extra info about command-line options used
when generating its advertisement heading, but we don't want that
here.

[InstCombine] remove stray auto-generated test comment; NFC

The script now includes extra info about command-line options used
when generating its advertisement heading, but we don't want that
here. This is a special-case because we have enhanced the check
lines (as noted in the 2nd comment line).

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[InstCombine] do not exclude min/max from icmp with casted operand fold

InstCombine has a mess of logic that tries to preserve min/max patterns,
but AFAICT, this one is not necessary because we can

[InstCombine] do not exclude min/max from icmp with casted operand fold

InstCombine has a mess of logic that tries to preserve min/max patterns,
but AFAICT, this one is not necessary because we can always narrow the
corresponding select in this sequence to match the narrow compare.

The biggest danger for this patch is inducing infinite looping or
assert from exceeding max iterations. If any bots hit that in the
vicinity of this commit, this is the likely patch to blame.

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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] use 'match' to handle vectors and simplify code

This is another step towards completely removing the fake
binop queries for not/neg/fneg.

llvm-svn: 345036

[InstCombine] swap select profile metadata when swapping select ops

llvm-svn: 345034

[InstCombine] add/move tests for select with inverted condition; NFC

The transform is broken in 2 ways - it doesn't correct metadata (or even drop it),
and it doesn't work with vectors with undef el

[InstCombine] add/move tests for select with inverted condition; NFC

The transform is broken in 2 ways - it doesn't correct metadata (or even drop it),
and it doesn't work with vectors with undef elements.

llvm-svn: 345033

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[InstCombine] Fold (min/max ~X, Y) -> ~(max/min X, ~Y) when Y is freely invertible

Summary: This restores the combine that was reverted in r341883. The infinite loop from the failing test no longer

[InstCombine] Fold (min/max ~X, Y) -> ~(max/min X, ~Y) when Y is freely invertible

Summary: This restores the combine that was reverted in r341883. The infinite loop from the failing test no longer occurs due to changes from r342163.

Reviewers: spatel, dmgreen

Reviewed By: spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D52070

llvm-svn: 342797

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