[InstCombine] Drop Range attribute when simplifying 'fshl' based on demanded bits (#124429)

When simplifying operands based on demanded bits, the return value range
of llvm.fshl might change. Keepi

[InstCombine] Drop Range attribute when simplifying 'fshl' based on demanded bits (#124429)

When simplifying operands based on demanded bits, the return value range
of llvm.fshl might change. Keeping the Range attribute might cause
llvm.fshl to generate a poison and lead to miscompile. Drop the Range
attribute similar to `dropPosonGeneratingFlags` elsewhere.

Fix #124387

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[InstCombine] Add test for incorrect retention of Range attribute in fshl

[InstCombine] Convert fshl(x, 0, y) to shl(x, and(y, BitWidth - 1)) when BitWidth is pow2 (#122362)

Convert `fshl(x, 0, y)` to `shl(x, and(y, BitWidth - 1))` when BitWidth
is pow2

Alive2 proof: htt

[InstCombine] Convert fshl(x, 0, y) to shl(x, and(y, BitWidth - 1)) when BitWidth is pow2 (#122362)

Convert `fshl(x, 0, y)` to `shl(x, and(y, BitWidth - 1))` when BitWidth
is pow2

Alive2 proof: https://alive2.llvm.org/ce/z/3oTEop
Fixes: #122235

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[InstCombine] Infer nusw + nneg -> nuw for getelementptr (#111144)

If the gep is nusw (usually via inbounds) and the offset is
non-negative, we can infer nuw.

Proof: https://alive2.llvm.org/ce/z

[InstCombine] Infer nusw + nneg -> nuw for getelementptr (#111144)

If the gep is nusw (usually via inbounds) and the offset is
non-negative, we can infer nuw.

Proof: https://alive2.llvm.org/ce/z/ihztLy

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[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] Fix incorrect fshr to fshl transform

This transform is only valid if the (modular) shift amount is not
zero.

Proof: https://alive2.llvm.org/ce/z/WBxn-x

Fixes https://github.com/llvm/

[InstCombine] Fix incorrect fshr to fshl transform

This transform is only valid if the (modular) shift amount is not
zero.

Proof: https://alive2.llvm.org/ce/z/WBxn-x

Fixes https://github.com/llvm/llvm-project/issues/89338.

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[InstCombine] Add test for incorrect fshr transform (#89338)

[InstCombine] Do not simplify lshr/shl arg if it is part of a rotate pattern

fshl/fshr having first two arguments as same gets lowered to target
specific rotate. But based on the uses, one of the ar

[InstCombine] Do not simplify lshr/shl arg if it is part of a rotate pattern

fshl/fshr having first two arguments as same gets lowered to target
specific rotate. But based on the uses, one of the arguments can get
simplified resulting in different arguments performing equivalent
operation.

This patch prevents the simplification of the arguments of lshr/shl if
they are part of fshl pattern.

Closes https://github.com/llvm/llvm-project/pull/73441.

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[InstCombine] Added additional funnel shift tests (NFC)

[InstCombine] Disable generation of fshl/fshr for rotates

Disable conversion of funnel shifts (fshl/fshr) into rotates
unless one of the operands is known to be a constant value.

Reviewed By: nikic

[InstCombine] Disable generation of fshl/fshr for rotates

Disable conversion of funnel shifts (fshl/fshr) into rotates
unless one of the operands is known to be a constant value.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D150670

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[InstCombine] Try to recognize bswap pattern when calling funnel shifts

Alive2: https://alive2.llvm.org/ce/z/dxxD7B
Fixes: https://github.com/llvm/llvm-project/issues/60690

Signed-off-by: Jun Zhang

[InstCombine] Try to recognize bswap pattern when calling funnel shifts

Alive2: https://alive2.llvm.org/ce/z/dxxD7B
Fixes: https://github.com/llvm/llvm-project/issues/60690

Signed-off-by: Jun Zhang <jun@junz.org>

Differential Revision: https://reviews.llvm.org/D146637

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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 type constraint to intrinsic+shuffle fold

This check is in the related fold for binops,
but it was missed when the code was adapted
for intrinsics in 432c199e8473. The new test
wou

[InstCombine] add type constraint to intrinsic+shuffle fold

This check is in the related fold for binops,
but it was missed when the code was adapted
for intrinsics in 432c199e8473. The new test
would crash when trying to create a new
intrinsic with mismatched types.

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[InstCombine] move shuffle after funnel shift with same-shuffled operands

This extends 432c199e8473 and 9c4770eaab9d9 with an intrinsic
cited directly in issue #46238

Eventually, we will want to us

[InstCombine] move shuffle after funnel shift with same-shuffled operands

This extends 432c199e8473 and 9c4770eaab9d9 with an intrinsic
cited directly in issue #46238

Eventually, we will want to use llvm::isTriviallyVectorizable()
or create some new API for this list, but for now, I am intentionally
making a minimum change to reduce risk and only affect an intrinsic
with regression tests in place.

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[InstCombine] add tests for funnel-shift with shuffled operands; 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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[InstCombine] Add undef funnel shift amount test coverage

Remove %tmp variables from test cases to appease update_test_checks.py

[InstCombine] Add test case showing rotate intrinsic being split by SimplifyDemandedBits

Noticed while triaging regression report on D88834

[InstCombine] matchRotate - support (uniform) constant rotation amounts (PR46895)

This patch adds handling of rotation patterns with constant shift amounts - the next bit will be how we want to supp

[InstCombine] matchRotate - support (uniform) constant rotation amounts (PR46895)

This patch adds handling of rotation patterns with constant shift amounts - the next bit will be how we want to support non-uniform constant vectors.

Differential Revision: https://reviews.llvm.org/D87452

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[InstCombine] reduce funnel-shift i16 X, X, 8 to bswap X

Prefer the more exact intrinsic to remove a use of the input value
and possibly make further transforms easier (we will still need
to match p

[InstCombine] reduce funnel-shift i16 X, X, 8 to bswap X

Prefer the more exact intrinsic to remove a use of the input value
and possibly make further transforms easier (we will still need
to match patterns with funnel-shift of wider types as pieces of
bswap, especially if we want to canonicalize to funnel-shift with
constant shift amount). Discussed in D46760.

llvm-svn: 364187

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[InstCombine] add tests for funnel-shift to bswap; NFC

llvm-svn: 364184

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] Prune fshl/fshr with masked operands

If a constant shift amount is used, then only some of the LHS/RHS
operand bits are demanded and we may be able to simplify based on
that. InstCombi

[InstCombine] Prune fshl/fshr with masked operands

If a constant shift amount is used, then only some of the LHS/RHS
operand bits are demanded and we may be able to simplify based on
that. InstCombineSimplifyDemanded already had the necessary support
for that, we just weren't calling it with fshl/fshr as root.

In particular, this allows us to relax some masked funnel shifts
into simple shifts, as shown in the tests.

Patch by Shawn Landden.

Differential Revision: https://reviews.llvm.org/D60660

llvm-svn: 358515

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