[SLP]Remove operands upon marking instruction for deletion.

If the instruction is marked for deletion, better to drop all its
operands and mark them for deletion too (if allowed). It allows to have

[SLP]Remove operands upon marking instruction for deletion.

If the instruction is marked for deletion, better to drop all its
operands and mark them for deletion too (if allowed). It allows to have
more vectorizable patterns and generate less useless extractelement
instructions.

Reviewers: RKSimon

Reviewed By: RKSimon

Pull Request: https://github.com/llvm/llvm-project/pull/97409

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Revert "[SLP]Remove operands upon marking instruction for deletion."

This reverts commit bbd52dd44ceee80e3b6ba6a9b2bd8ee9a9713833 to fix
a crash revealed in https://lab.llvm.org/buildbot/#/builders/

Revert "[SLP]Remove operands upon marking instruction for deletion."

This reverts commit bbd52dd44ceee80e3b6ba6a9b2bd8ee9a9713833 to fix
a crash revealed in https://lab.llvm.org/buildbot/#/builders/4/builds/505

show more ...

[SLP]Remove operands upon marking instruction for deletion.

If the instruction is marked for deletion, better to drop all its
operands and mark them for deletion too (if allowed). It allows to have

[SLP]Remove operands upon marking instruction for deletion.

If the instruction is marked for deletion, better to drop all its
operands and mark them for deletion too (if allowed). It allows to have
more vectorizable patterns and generate less useless extractelement
instructions.

Reviewers: RKSimon

Reviewed By: RKSimon

Pull Request: https://github.com/llvm/llvm-project/pull/97409

show more ...

[SLP] Convert some tests to opaque pointers (NFC)

[test][SLPVectorizer] Use -passes syntax in RUN lines. NFC

[opt] Don't translate legacy -analysis flag to require<analysis>

Tests relying on this should explicitly use -passes='require<analysis>,foo'.

[CostModel][X86] Add CostKinds handling for smax/smin/umax/umin instructions

This was achieved with the 'cost-tables vs llvm-mca' script D103695

[CostModel][X86] Adjust SLM select costs to match poor throughput of pblendvb/blendvpd/blendvps

Reapply "[SLP] Schedule only sub-graph of vectorizable instructions"" (try 3)

The original commit exposed several missing dependencies (e.g. latent bugs in SLP scheduling). Most of these were fixed

Reapply "[SLP] Schedule only sub-graph of vectorizable instructions"" (try 3)

The original commit exposed several missing dependencies (e.g. latent bugs in SLP scheduling). Most of these were fixed over the weekend and have had several days to bake. The last was fixed this morning after being noticed in manual review of test changes yesterday. See the review thread for links to each change.

Original commit message follows:

SLP currently schedules all instructions within a scheduling window which stretches from the first instruction potentially vectorized to the last. This window can include a very large number of unrelated instructions which are not being considered for vectorization. This change switches the code to only schedule the sub-graph consisting of the instructions being vectorized and their transitive users.

This has the effect of greatly reducing the amount of work performed in large basic blocks, and thus greatly improves compile time on degenerate examples. To understand the effects, I added some statistics (not planned for upstream contribution). Here's an illustration from my motivating example:

Before this patch:

704357 SLP - Number of calcDeps actions
699021 SLP - Number of schedule calls
5598 SLP - Number of ReSchedule actions
59 SLP - Number of ReScheduleOnFail actions
10084 SLP - Number of schedule resets
8523 SLP - Number of vector instructions generated

After this patch:

102895 SLP - Number of calcDeps actions
161916 SLP - Number of schedule calls
5637 SLP - Number of ReSchedule actions
55 SLP - Number of ReScheduleOnFail actions
10083 SLP - Number of schedule resets
8403 SLP - Number of vector instructions generated

I do want to highlight that there is a small difference in number of generated vector instructions. This example is hitting the bailout due to maximum window size, and the change in scheduling is slightly perturbing when and how we hit it. This can be seen in the RescheduleOnFail counter change. Given that, I think we can safely ignore.

The downside of this change can be seen in the large test diff. We group all vectorizable instructions together at the bottom of the scheduling region. This means that vector instructions can move quite far from their original point in code. While maybe undesirable, I don't see this as being a major problem as this pass is not intended to be a general scheduling pass.

For context, it's worth noting that the pre-scheduling that SLP does while building the vector tree is exactly the sub-graph scheduling implemented by this patch.

Differential Revision: https://reviews.llvm.org/D118538

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Revert "Reapply "[SLP] Schedule only sub-graph of vectorizable instructions"""

This reverts commit 738042711bc08cde9135873200b1d088e6cf11c3. A second, apparently separate, issue has been reported on

Revert "Reapply "[SLP] Schedule only sub-graph of vectorizable instructions"""

This reverts commit 738042711bc08cde9135873200b1d088e6cf11c3. A second, apparently separate, issue has been reported on the original review.

show more ...

Reapply "[SLP] Schedule only sub-graph of vectorizable instructions""

Root issue which triggered the revert was fixed in 689bab. No changes in the reapplied patch.

Original commit message follows:

Reapply "[SLP] Schedule only sub-graph of vectorizable instructions""

Root issue which triggered the revert was fixed in 689bab. No changes in the reapplied patch.

Original commit message follows:

SLP currently schedules all instructions within a scheduling window which stretches from the first instr
uction potentially vectorized to the last. This window can include a very large number of unrelated instruct
ions which are not being considered for vectorization. This change switches the code to only schedule the su
b-graph consisting of the instructions being vectorized and their transitive users.

This has the effect of greatly reducing the amount of work performed in large basic blocks, and thus greatly improves compile time on degenerate examples. To understand the effects, I added some statistics (not planned for upstream contribution). Here's an illustration from my motivating example:

Before this patch:

704357 SLP - Number of calcDeps actions
699021 SLP - Number of schedule calls
5598 SLP - Number of ReSchedule actions
59 SLP - Number of ReScheduleOnFail actions
10084 SLP - Number of schedule resets
8523 SLP - Number of vector instructions generated

After this patch:

102895 SLP - Number of calcDeps actions
161916 SLP - Number of schedule calls
5637 SLP - Number of ReSchedule actions
55 SLP - Number of ReScheduleOnFail actions
10083 SLP - Number of schedule resets
8403 SLP - Number of vector instructions generated

I do want to highlight that there is a small difference in number of generated vector instructions. This example is hitting the bailout due to maximum window size, and the change in scheduling is slightly perturbing when and how we hit it. This can be seen in the RescheduleOnFail counter change. Given that, I think we can safely ignore.

The downside of this change can be seen in the large test diff. We group all vectorizable instructions together at the bottom of the scheduling region. This means that vector instructions can move quite far from their original point in code. While maybe undesirable, I don't see this as being a major problem as this pass is not intended to be a general scheduling pass.

For context, it's worth noting that the pre-scheduling that SLP does while building the vector tree is exactly the sub-graph scheduling implemented by this patch.

Differential Revision: https://reviews.llvm.org/D118538

show more ...

Revert "[SLP] Schedule only sub-graph of vectorizable instructions"

This reverts commit 0539a26d91a1b7c74022fa9cf33bd7faca87544d.

Causes a miscompile, see comments on D118538.

Required updating bo

Revert "[SLP] Schedule only sub-graph of vectorizable instructions"

This reverts commit 0539a26d91a1b7c74022fa9cf33bd7faca87544d.

Causes a miscompile, see comments on D118538.

Required updating bottom-to-top-reorder.ll.

show more ...

[SLP] Schedule only sub-graph of vectorizable instructions

SLP currently schedules all instructions within a scheduling window which stretches from the first instruction potentially vectorized to th

[SLP] Schedule only sub-graph of vectorizable instructions

SLP currently schedules all instructions within a scheduling window which stretches from the first instruction potentially vectorized to the last. This window can include a very large number of unrelated instructions which are not being considered for vectorization. This change switches the code to only schedule the sub-graph consisting of the instructions being vectorized and their transitive users.

This has the effect of greatly reducing the amount of work performed in large basic blocks, and thus greatly improves compile time on degenerate examples. To understand the effects, I added some statistics (not planned for upstream contribution). Here's an illustration from my motivating example:

Before this patch:

704357 SLP - Number of calcDeps actions
699021 SLP - Number of schedule calls
5598 SLP - Number of ReSchedule actions
59 SLP - Number of ReScheduleOnFail actions
10084 SLP - Number of schedule resets
8523 SLP - Number of vector instructions generated

After this patch:

102895 SLP - Number of calcDeps actions
161916 SLP - Number of schedule calls
5637 SLP - Number of ReSchedule actions
55 SLP - Number of ReScheduleOnFail actions
10083 SLP - Number of schedule resets
8403 SLP - Number of vector instructions generated

I do want to highlight that there is a small difference in number of generated vector instructions. This example is hitting the bailout due to maximum window size, and the change in scheduling is slightly perturbing when and how we hit it. This can be seen in the RescheduleOnFail counter change. Given that, I think we can safely ignore.

The downside of this change can be seen in the large test diff. We group all vectorizable instructions together at the bottom of the scheduling region. This means that vector instructions can move quite far from their original point in code. While maybe undesirable, I don't see this as being a major problem as this pass is not intended to be a general scheduling pass.

For context, it's worth noting that the pre-scheduling that SLP does while building the vector tree is exactly the sub-graph scheduling implemented by this patch.

Differential Revision: https://reviews.llvm.org/D118538

show more ...

[SLPVectorizer][X86] Remove unused check-prefixes

[SLP][X86] Add abs/smax/smin/umax/umin intrinsic vectorization tests