[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] Handle commuted variant of sqrt transform

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

[InstCombine] Fix name clashes in check lines (NFC)

These used both lower and upper case variants of the same name,
resulting in malformed check lines when regenerated.

[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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Update foldFMulReassoc to respect absent fast-math flags (#88589)

This change updates a few of the transformations in foldFMulReassoc to
respect absent fast-math flags in cases where fmul and fdiv,

Update foldFMulReassoc to respect absent fast-math flags (#88589)

This change updates a few of the transformations in foldFMulReassoc to
respect absent fast-math flags in cases where fmul and fdiv, fadd, or fsub
instructions were being folded but the code was only checking for
fast-math flags on the fmul instruction and was transferring flags to
the folded instruction that were not present on the other original
instructions.

This fixes https://github.com/llvm/llvm-project/issues/82857

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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] 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] remove fsub to fneg hacks; only emit fneg

Summary: Rewrite the fsub-0.0 idiom to fneg and always emit fneg for fp
negation. This also extends the scalarization cost in instcombine for

[instcombine] remove fsub to fneg hacks; only emit fneg

Summary: Rewrite the fsub-0.0 idiom to fneg and always emit fneg for fp
negation. This also extends the scalarization cost in instcombine for unary
operators to result in the same IR rewrites for fneg as for the idiom.

Reviewed By: cameron.mcinally

Differential Revision: https://reviews.llvm.org/D75467

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Remove BinaryOperator::CreateFNeg

Use UnaryOperator::CreateFNeg instead.

Summary:
With the introduction of the native fneg instruction, the
fsub -0.0, %x idiom is obsolete. This patch makes LLVM
em

Remove BinaryOperator::CreateFNeg

Use UnaryOperator::CreateFNeg instead.

Summary:
With the introduction of the native fneg instruction, the
fsub -0.0, %x idiom is obsolete. This patch makes LLVM
emit fneg instead of the idiom in all places.

Reviewed By: cameron.mcinally

Differential Revision: https://reviews.llvm.org/D75130

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[IRBuilder] Update IRBuilder::CreateFNeg(...) to return a UnaryOperator

Reapply r374240 with fix for Ocaml test, namely Bindings/OCaml/core.ml.

Differential Revision: https://reviews.llvm.org/D6167

[IRBuilder] Update IRBuilder::CreateFNeg(...) to return a UnaryOperator

Reapply r374240 with fix for Ocaml test, namely Bindings/OCaml/core.ml.

Differential Revision: https://reviews.llvm.org/D61675

llvm-svn: 374782

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Revert "[IRBuilder] Update IRBuilder::CreateFNeg(...) to return a UnaryOperator"

This reverts commit r374240. It broke OCaml tests:
http://lab.llvm.org:8011/builders/clang-x86_64-debian-fast/builds/

Revert "[IRBuilder] Update IRBuilder::CreateFNeg(...) to return a UnaryOperator"

This reverts commit r374240. It broke OCaml tests:
http://lab.llvm.org:8011/builders/clang-x86_64-debian-fast/builds/19014

llvm-svn: 374354

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[IRBuilder] Update IRBuilder::CreateFNeg(...) to return a UnaryOperator

Also update Clang to call Builder.CreateFNeg(...) for UnaryMinus.

Differential Revision: https://reviews.llvm.org/D61675

llv

[IRBuilder] Update IRBuilder::CreateFNeg(...) to return a UnaryOperator

Also update Clang to call Builder.CreateFNeg(...) for UnaryMinus.

Differential Revision: https://reviews.llvm.org/D61675

llvm-svn: 374240

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[InstCombine] canonicalize fmin/fmax to LLVM intrinsics minnum/maxnum

This transform came up in D62414, but we should deal with it first.
We have LLVM intrinsics that correspond exactly to libm call

[InstCombine] canonicalize fmin/fmax to LLVM intrinsics minnum/maxnum

This transform came up in D62414, but we should deal with it first.
We have LLVM intrinsics that correspond exactly to libm calls (unlike
most libm calls, these libm calls never set errno).
This holds without any fast-math-flags, so we should always canonicalize
to those intrinsics directly for better optimization.
Currently, we convert to fcmp+select only when we have FMF (nnan) because
fcmp+select does not preserve the semantics of the call in the general case.

Differential Revision: https://reviews.llvm.org/D63214

llvm-svn: 364714

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[InstCombine] add tests for fmin/fmax libcalls; NFC

llvm-svn: 363175

[IR] allow fast-math-flags on select of FP values

This is a minimal start to correcting a problem most directly discussed in PR38086:
https://bugs.llvm.org/show_bug.cgi?id=38086

We have been hackin

[IR] allow fast-math-flags on select of FP values

This is a minimal start to correcting a problem most directly discussed in PR38086:
https://bugs.llvm.org/show_bug.cgi?id=38086

We have been hacking around a limitation for FP select patterns by using the
fast-math-flags on the condition of the select rather than the select itself.
This patch just allows FMF to appear with the 'select' opcode. No changes are
needed to "FPMathOperator" because it already includes select-of-FP because
that definition is based on the (return) value type.

Once we have this ability, we can start correcting and adding IR transforms
to use the FMF on a 'select' instruction. The instcombine and vectorizer test
diffs only show that the IRBuilder change is behaving as expected by applying
an FMF guard value to 'select'.

For reference:
rL241901 - allowed FMF with fcmp
rL255555 - allowed FMF with FP calls

Differential Revision: https://reviews.llvm.org/D61917

llvm-svn: 361401

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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 fdiv after fmul if reassociation is allowed

(X / Y) * Z --> (X * Z) / Y

This can allow other optimizations/reassociations as shown in the test diffs.

llvm-svn: 358404

[InstCombine] move/add tests for fadd/fsub factorization; NFC

llvm-svn: 339518

[InstCombine] add tests for fsub factorization; NFC

The tests show that;
1. The fold doesn't fire for vectors, but it should.
2. The fold fires regardless of uses, but it shouldn't.

llvm-svn: 339470

[InstCombine] allow fsub+fmul FMF folds for vectors

llvm-svn: 339368

[InstCombine] add vector tests for fsub+fmul; NFC

llvm-svn: 339361

[InstCombine] fold fadd+fsub with common operand

This is a sibling to the simplify from:
https://reviews.llvm.org/rL339174

llvm-svn: 339267

[InstCombine] fold fsub+fsub with common operand

This is a sibling to the simplify from:
rL339171

llvm-svn: 339266