History log of /llvm-project/llvm/test/Transforms/InstCombine/vector-udiv.ll (Results 1 – 10 of 10)
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Revision tags: llvmorg-21-init, llvmorg-19.1.7, llvmorg-19.1.6, llvmorg-19.1.5, llvmorg-19.1.4
# 38fffa63 06-Nov-2024 Paul Walker <paul.walker@arm.com>

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


# a77dedca 01-Nov-2024 Yingwei Zheng <dtcxzyw2333@gmail.com>

[InstSimplify][InstCombine][ConstantFold] Move vector div/rem by zero fold to InstCombine (#114280)

Previously we fold `div/rem X, C` into `poison` if any element of the
constant divisor `C` is zer

[InstSimplify][InstCombine][ConstantFold] Move vector div/rem by zero fold to InstCombine (#114280)

Previously we fold `div/rem X, C` into `poison` if any element of the
constant divisor `C` is zero or undef. However, it is incorrect when
threading udiv over an vector select:
https://alive2.llvm.org/ce/z/3Ninx5
```
define <2 x i32> @vec_select_udiv_poison(<2 x i1> %x) {
%sel = select <2 x i1> %x, <2 x i32> <i32 -1, i32 -1>, <2 x i32> <i32 0, i32 1>
%div = udiv <2 x i32> <i32 42, i32 -7>, %sel
ret <2 x i32> %div
}
```
In this case, `threadBinOpOverSelect` folds `udiv <i32 42, i32 -7>, <i32
-1, i32 -1>` and `udiv <i32 42, i32 -7>, <i32 0, i32 1>` into
`zeroinitializer` and `poison`, respectively. One solution is to
introduce a new flag indicating that we are threading over a vector
select. But it requires to modify both `InstSimplify` and
`ConstantFold`.

However, this optimization doesn't provide benefits to real-world
programs:

https://dtcxzyw.github.io/llvm-opt-benchmark/coverage/data/zyw/opt-ci/actions-runner/_work/llvm-opt-benchmark/llvm-opt-benchmark/llvm/llvm-project/llvm/lib/IR/ConstantFold.cpp.html#L908

https://dtcxzyw.github.io/llvm-opt-benchmark/coverage/data/zyw/opt-ci/actions-runner/_work/llvm-opt-benchmark/llvm-opt-benchmark/llvm/llvm-project/llvm/lib/Analysis/InstructionSimplify.cpp.html#L1107

This patch moves the fold into InstCombine to avoid breaking numerous
existing tests.

Fixes #114191 and #113866 (only poison-safety issue).

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Revision tags: llvmorg-19.1.3, llvmorg-19.1.2, llvmorg-19.1.1, llvmorg-19.1.0, llvmorg-19.1.0-rc4, llvmorg-19.1.0-rc3, llvmorg-19.1.0-rc2, llvmorg-19.1.0-rc1, llvmorg-20-init, llvmorg-18.1.8, llvmorg-18.1.7, llvmorg-18.1.6, llvmorg-18.1.5, llvmorg-18.1.4, llvmorg-18.1.3, llvmorg-18.1.2, llvmorg-18.1.1, llvmorg-18.1.0, llvmorg-18.1.0-rc4, llvmorg-18.1.0-rc3, llvmorg-18.1.0-rc2, llvmorg-18.1.0-rc1, llvmorg-19-init, llvmorg-17.0.6, llvmorg-17.0.5
# 44cdbef7 13-Nov-2023 Yingwei Zheng <dtcxzyw2333@gmail.com>

[InstCombine] Infer nneg flag from shift users (#71947)

This patch sets `nneg` flag when the zext is only used by a shift.

Alive2: https://alive2.llvm.org/ce/z/h3xKjP
Compile-time impact:
https

[InstCombine] Infer nneg flag from shift users (#71947)

This patch sets `nneg` flag when the zext is only used by a shift.

Alive2: https://alive2.llvm.org/ce/z/h3xKjP
Compile-time impact:
https://llvm-compile-time-tracker.com/compare.php?from=bd611264993f64decbce178d460caf1d1cb05f59&to=26bc473b239010bb24ff1bc39d58b42ecbbc4730&stat=instructions:u

This is an alternative to #71906.

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Revision tags: llvmorg-17.0.4, llvmorg-17.0.3, llvmorg-17.0.2, llvmorg-17.0.1, llvmorg-17.0.0, llvmorg-17.0.0-rc4, llvmorg-17.0.0-rc3, llvmorg-17.0.0-rc2, llvmorg-17.0.0-rc1, llvmorg-18-init, llvmorg-16.0.6, llvmorg-16.0.5, llvmorg-16.0.4, llvmorg-16.0.3, llvmorg-16.0.2, llvmorg-16.0.1, llvmorg-16.0.0, llvmorg-16.0.0-rc4, llvmorg-16.0.0-rc3, llvmorg-16.0.0-rc2, llvmorg-16.0.0-rc1, llvmorg-17-init, llvmorg-15.0.7, llvmorg-15.0.6, llvmorg-15.0.5, llvmorg-15.0.4, llvmorg-15.0.3, working, llvmorg-15.0.2, llvmorg-15.0.1, llvmorg-15.0.0, llvmorg-15.0.0-rc3, llvmorg-15.0.0-rc2, llvmorg-15.0.0-rc1, llvmorg-16-init, llvmorg-14.0.6, llvmorg-14.0.5, llvmorg-14.0.4, llvmorg-14.0.3, llvmorg-14.0.2, llvmorg-14.0.1, llvmorg-14.0.0, llvmorg-14.0.0-rc4, llvmorg-14.0.0-rc3, llvmorg-14.0.0-rc2, llvmorg-14.0.0-rc1
# acdc419c 04-Feb-2022 Bjorn Pettersson <bjorn.a.pettersson@ericsson.com>

[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

show more ...


Revision tags: llvmorg-15-init, llvmorg-13.0.1, llvmorg-13.0.1-rc3, llvmorg-13.0.1-rc2, llvmorg-13.0.1-rc1, llvmorg-13.0.0, llvmorg-13.0.0-rc4, llvmorg-13.0.0-rc3, llvmorg-13.0.0-rc2, llvmorg-13.0.0-rc1, llvmorg-14-init, llvmorg-12.0.1, llvmorg-12.0.1-rc4, llvmorg-12.0.1-rc3, llvmorg-12.0.1-rc2, llvmorg-12.0.1-rc1, llvmorg-12.0.0, llvmorg-12.0.0-rc5, llvmorg-12.0.0-rc4, llvmorg-12.0.0-rc3, llvmorg-12.0.0-rc2, llvmorg-11.1.0, llvmorg-11.1.0-rc3, llvmorg-12.0.0-rc1, llvmorg-13-init, llvmorg-11.1.0-rc2, llvmorg-11.1.0-rc1
# 766cf7f3 03-Jan-2021 Nikita Popov <nikita.ppv@gmail.com>

[InstSimplify] Fold division by zero to poison

Div/rem by zero is immediate undefined behavior and anything goes.
Currently we fold it to undef, this patch changes it to fold to
poison instead, whic

[InstSimplify] Fold division by zero to poison

Div/rem by zero is immediate undefined behavior and anything goes.
Currently we fold it to undef, this patch changes it to fold to
poison instead, which is slightly stronger.

Differential Revision: https://reviews.llvm.org/D93995

show more ...


Revision tags: llvmorg-11.0.1, llvmorg-11.0.1-rc2, llvmorg-11.0.1-rc1, llvmorg-11.0.0, llvmorg-11.0.0-rc6, llvmorg-11.0.0-rc5, llvmorg-11.0.0-rc4, llvmorg-11.0.0-rc3, llvmorg-11.0.0-rc2, llvmorg-11.0.0-rc1, llvmorg-12-init, llvmorg-10.0.1, llvmorg-10.0.1-rc4, llvmorg-10.0.1-rc3, llvmorg-10.0.1-rc2, llvmorg-10.0.1-rc1, llvmorg-10.0.0, llvmorg-10.0.0-rc6, llvmorg-10.0.0-rc5, llvmorg-10.0.0-rc4, llvmorg-10.0.0-rc3, llvmorg-10.0.0-rc2, llvmorg-10.0.0-rc1, llvmorg-11-init, llvmorg-9.0.1, llvmorg-9.0.1-rc3, llvmorg-9.0.1-rc2, llvmorg-9.0.1-rc1, llvmorg-9.0.0, llvmorg-9.0.0-rc6, llvmorg-9.0.0-rc5, llvmorg-9.0.0-rc4, llvmorg-9.0.0-rc3, llvmorg-9.0.0-rc2, llvmorg-9.0.0-rc1, llvmorg-10-init, llvmorg-8.0.1, llvmorg-8.0.1-rc4, llvmorg-8.0.1-rc3, llvmorg-8.0.1-rc2, llvmorg-8.0.1-rc1
# cee313d2 17-Apr-2019 Eric Christopher <echristo@gmail.com>

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

The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552


Revision tags: llvmorg-8.0.0, llvmorg-8.0.0-rc5, llvmorg-8.0.0-rc4, llvmorg-8.0.0-rc3, llvmorg-7.1.0, llvmorg-7.1.0-rc1, llvmorg-8.0.0-rc2, llvmorg-8.0.0-rc1, llvmorg-7.0.1, llvmorg-7.0.1-rc3, llvmorg-7.0.1-rc2, llvmorg-7.0.1-rc1, llvmorg-7.0.0, llvmorg-7.0.0-rc3, llvmorg-7.0.0-rc2, llvmorg-7.0.0-rc1, llvmorg-6.0.1, llvmorg-6.0.1-rc3, llvmorg-6.0.1-rc2, llvmorg-6.0.1-rc1, llvmorg-5.0.2, llvmorg-5.0.2-rc2, llvmorg-5.0.2-rc1, llvmorg-6.0.0, llvmorg-6.0.0-rc3
# 9620f4b7 09-Feb-2018 Simon Pilgrim <llvm-dev@redking.me.uk>

[InstCombine] Add constant vector support for X udiv C, where C >= signbit

llvm-svn: 324728


# f30656ad 08-Feb-2018 Simon Pilgrim <llvm-dev@redking.me.uk>

[InstCombine] Add vector udiv tests

Tests for X udiv C, where C >= signbit

llvm-svn: 324635


# 2a90acd1 08-Feb-2018 Simon Pilgrim <llvm-dev@redking.me.uk>

[InstCombine] Fix issue with X udiv (POW2_C1 << N) for non-splat constant vectors

foldUDivShl was assuming that the input was a scalar or a splat constant

llvm-svn: 324613


# 94cc89d5 08-Feb-2018 Simon Pilgrim <llvm-dev@redking.me.uk>

[InstCombine] Fix issue with X udiv 2^C -> X >> C for non-splat constant vectors

foldUDivPow2Cst was assuming that the input was a scalar or a splat constant

llvm-svn: 324608