[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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[InstCombine] Fold `(add X, (sext/zext (icmp eq X, C)))`

We can convert this to a select based on the `(icmp eq X, C)`, then
constant fold the addition the true arm begin `(add C, (sext/zext 1))`
an

[InstCombine] Fold `(add X, (sext/zext (icmp eq X, C)))`

We can convert this to a select based on the `(icmp eq X, C)`, then
constant fold the addition the true arm begin `(add C, (sext/zext 1))`
and the false arm being `(add X, 0)` e.g

- `(select (icmp eq X, C), (add C, (sext/zext 1)), (add X, 0))`.

This is essentially a specialization of the only case that sees to
actually show up from #89020

Closes #93840

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[InstCombine] Infer disjoint flag on Or instructions. (#72912)

The disjoint flag was recently added to IR in #72583

We already set it when we turn an add into an or. This patch sets it on Ors tha

[InstCombine] Infer disjoint flag on Or instructions. (#72912)

The disjoint flag was recently added to IR in #72583

We already set it when we turn an add into an or. This patch sets it on Ors that weren't converted from an Add.

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[InstCombine] Set disjoint flag when turning Add into Or. (#72702)

The disjoint flag was recently added to IR in #72583

[InferAlignment] Enable InferAlignment pass by default

This gives an improvement of 0.6%:
https://llvm-compile-time-tracker.com/compare.php?from=7d35fe6d08e2b9b786e1c8454cd2391463832167&to=0456c8e8a

[InferAlignment] Enable InferAlignment pass by default

This gives an improvement of 0.6%:
https://llvm-compile-time-tracker.com/compare.php?from=7d35fe6d08e2b9b786e1c8454cd2391463832167&to=0456c8e8a42be06b62ad4c3e3cf34b21f2633d1e&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D158600

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[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] Add mul with negated power of 2 constant to canEvaluateShifted.

If we are right shifting a multiply by a negated power of 2 where
the power of 2 is the same as the shift amount, we can

[InstCombine] Add mul with negated power of 2 constant to canEvaluateShifted.

If we are right shifting a multiply by a negated power of 2 where
the power of 2 is the same as the shift amount, we can replace with
a negate followed by an And.

New tests have not been committed yet but the patch shows the diffs.
Let me know if you want any changes or additional tests.

Differential Revision: https://reviews.llvm.org/D130103

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Revert "[InstCombine] Add one use limitation for (X * C2) << C1 --> X * (C2 << C1)"

This reverts commit b543d28df7b067dcda833c717a59faa28c1151a1.

[InstCombine] Add one use limitation for (X * C2) << C1 --> X * (C2 << C1)

Follow up D123453, add one-use limitation for
(X * C2) << C1 --> X * (C2 << C1)
to make consistent with
lshr (mul nuw x, M

[InstCombine] Add one use limitation for (X * C2) << C1 --> X * (C2 << C1)

Follow up D123453, add one-use limitation for
(X * C2) << C1 --> X * (C2 << C1)
to make consistent with
lshr (mul nuw x, MulC), ShAmtC -> mul nuw x, (MulC >> ShAmtC)

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D124183

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[InstCombine] add baseline test for (X * C2) << C1 --> X * (C2 << C1) without one use; NFC

[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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Reapply [ConstantFold] Fold more operations to poison

This was reverted to mitigate mitigate miscompiles caused by
the logical and/or to bitwise and/or fold. Reapply it now that
the underlying issue

Reapply [ConstantFold] Fold more operations to poison

This was reverted to mitigate mitigate miscompiles caused by
the logical and/or to bitwise and/or fold. Reapply it now that
the underlying issue has been fixed by D101191.

-----

This patch folds more operations to poison.

Alive2 proof: https://alive2.llvm.org/ce/z/mxcb9G (it does not contain tests about div/rem because they fold to poison when raising UB)

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D92270

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Revert "[ConstantFold] Fold more operations to poison"

This reverts commit 53040a968dc2ff20931661e55f05da2ef8b964a0 due to its
bad interaction with select i1 -> and/or i1 transformation.

This fixes

Revert "[ConstantFold] Fold more operations to poison"

This reverts commit 53040a968dc2ff20931661e55f05da2ef8b964a0 due to its
bad interaction with select i1 -> and/or i1 transformation.

This fixes:
https://bugs.llvm.org/show_bug.cgi?id=49005
https://bugs.llvm.org/show_bug.cgi?id=48435

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[ConstantFold] Fold more operations to poison

This patch folds more operations to poison.

Alive2 proof: https://alive2.llvm.org/ce/z/mxcb9G (it does not contain tests about div/rem because they fol

[ConstantFold] Fold more operations to poison

This patch folds more operations to poison.

Alive2 proof: https://alive2.llvm.org/ce/z/mxcb9G (it does not contain tests about div/rem because they fold to poison when raising UB)

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D92270

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[NFC][InstCombine] Update few comment updates i missed in 0ac56e8eaaeb

As pointed out in post-commit review in that commit

[InstCombine] Fold `(X >>? C1) << C2` patterns to shift+bitmask (PR37872)

This is essentially finalizes a revert of rL155136,
because nowadays the situation has improved, SCEV can model
all these pa

[InstCombine] Fold `(X >>? C1) << C2` patterns to shift+bitmask (PR37872)

This is essentially finalizes a revert of rL155136,
because nowadays the situation has improved, SCEV can model
all these patterns well, and we canonicalize rotate-like patterns
into a funnel shift intrinsics in InstCombine.
So this should not cause any pessimization.

I've verified the canonicalize-{a,l}shr-shl-to-masking.ll transforms
with alive, which confirms that we can freely preserve exact-ness,
and no-wrap flags.

Profs:
* base: https://rise4fun.com/Alive/gPQ
* exact-ness preservation: https://rise4fun.com/Alive/izi
* nuw preservation: https://rise4fun.com/Alive/DmD
* nsw preservation: https://rise4fun.com/Alive/SLN6N
* nuw nsw preservation: https://rise4fun.com/Alive/Qp7

Refs. https://reviews.llvm.org/D46760

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[InstCombine] Add (vXi1 trunc(lshr(x,c))) -> icmp_eq(and(x,c')) support for non-uniform vectors

As noted on PR46531, we were only performing this transform on uniform vectors as we were using the m_

[InstCombine] Add (vXi1 trunc(lshr(x,c))) -> icmp_eq(and(x,c')) support for non-uniform vectors

As noted on PR46531, we were only performing this transform on uniform vectors as we were using the m_APInt pattern matcher to extract the shift amount.

Differential Revision: https://reviews.llvm.org/D83035

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[InstCombine] Add some (vXi1 trunc(lshr(x,c))) -> icmp_eq(and(x,c')) tests for vectors with undef elements

Suggested on D83035

[InstCombine] Add some (vXi1 trunc(lshr(x,c))) -> icmp_eq(and(x,c')) tests for non-uniform vectors

As noticed on PR46531

Regenerate apint-shift tests and replace %tmp variable names to silence update_test_checks warnings

[InstCombine] Invert `add A, sext(B) --> sub A, zext(B)` canonicalization (to `sub A, zext B -> add A, sext B`)

Summary:
D68408 proposes to greatly improve our negation sinking abilities.
But in cur

[InstCombine] Invert `add A, sext(B) --> sub A, zext(B)` canonicalization (to `sub A, zext B -> add A, sext B`)

Summary:
D68408 proposes to greatly improve our negation sinking abilities.
But in current canonicalization, we produce `sub A, zext(B)`,
which we will consider non-canonical and try to sink that negation,
undoing the existing canonicalization.
So unless we explicitly stop producing previous canonicalization,
we will have two conflicting folds, and will end up endlessly looping.

This inverts canonicalization, and adds back the obvious fold
that we'd miss:
* `sub [nsw] Op0, sext/zext (bool Y) -> add [nsw] Op0, zext/sext (bool Y)`
https://rise4fun.com/Alive/xx4
* `sext(bool) + C -> bool ? C - 1 : C`
https://rise4fun.com/Alive/fBl

It is obvious that `@ossfuzz_9880()` / `@lshr_out_of_range()`/`@ashr_out_of_range()`
(oss-fuzz 4871) are no longer folded as much, though those aren't really worrying.

Reviewers: spatel, efriedma, t.p.northover, hfinkel

Reviewed By: spatel

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71064

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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] canonicalize add/sub with bool

add A, sext(B) --> sub A, zext(B)

We have to choose 1 of these forms, so I'm opting for the
zext because that's easier for value tracking.

The backend

[InstCombine] canonicalize add/sub with bool

add A, sext(B) --> sub A, zext(B)

We have to choose 1 of these forms, so I'm opting for the
zext because that's easier for value tracking.

The backend should be prepared for this change after:
D57401
rL353433

This is also a preliminary step towards reducing the amount
of bit hackery that we do in IR to optimize icmp/select.
That should be waiting to happen at a later optimization stage.

The seeming regression in the fuzzer test was discussed in:
D58359

We were only managing that fold in instcombine by luck, and
other passes should be able to deal with that better anyway.

llvm-svn: 354748

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