75 Commits

Author SHA1 Message Date
Florian Hahn
c836983671
[VPlan] Remove unused first mask op from VPBlendRecipe. (#87770)
VPBlendRecipe does not use the first mask operand. Removing it allows
VPlan-based DCE to remove unused mask computations.

This also fixes #87410, where unused Not VPInstructions are considered
having only their first lane demanded, but some of their operands
providing a vector value due to other users.

Fixes https://github.com/llvm/llvm-project/issues/87410

PR: https://github.com/llvm/llvm-project/pull/87770
2024-04-09 11:14:05 +01:00
Florian Hahn
51afb10174
[LV] Create block in mask up-front if needed. (#76635)
At the moment, block and edge masks are created on demand, which means
that they are inserted at the point where they are demanded and then
cached. It is possible that the mask for a block is looked up later at a
point that's not dominated by the point where the mask has been
inserted.

To avoid this, create masks up front on entry to the corresponding basic
block and leave it to VPlan simplification to remove unneeded masks.

Note that we need to create masks for all blocks, if any of the blocks
in the loop needs predication, as computing the mask of a block depends
on the masks of its predecessor.

Needed for #76090.

https://github.com/llvm/llvm-project/pull/76635
2024-01-09 10:50:08 +00:00
Florian Hahn
241fe83704
[VPlan] Introduce ComputeReductionResult VPInstruction opcode. (#70253)
This patch introduces a new ComputeReductionResult opcode to compute the
final reduction result in the middle block. The code from fixReduction
has been moved to ComputeReductionResult, after some earlier cleanup
changes to model parts of fixReduction explicitly elsewhere as needed.

The recipe may be broken down further in the future.

Note that  the phi nodes to merge the reduction result from the trip 
count check and the middle block, to be used as resume value for the
scalar remainder loop are also generated based on 
ComputeReductionResult.

Once we have a VPValue for the reduction result, this can also be
modeled explicitly and moved out of the recipe.
2024-01-04 22:53:18 +00:00
Florian Hahn
f18536d642
[VPlan] Model address separately. (#72164)
Move vector pointer generation to a separate VPVectorPointerRecipe.
This untangles address computation from the memory recipes future
and is also needed to enable explicit unrolling in VPlan.

https://github.com/llvm/llvm-project/pull/72164
2024-01-01 19:51:15 +00:00
Florian Hahn
a5891fa4d2
[VPlan] Initial modeling of VF * UF as VPValue. (#74761)
This patch starts initial modeling of VF * UF in VPlan.
Initially, introduce a dedicated VFxUF VPValue, which is then
populated during VPlan::prepareToExecute. Initially, the VF * UF
applies only to the main vector loop region. Once we extend the
scope of VPlan in the future, we may want to associate different VFxUFs
with different vector loop regions (e.g. the epilogue vector loop)

This allows explicitly parameterizing recipes that rely on the
VF * UF, like the canonical induction increment. At the moment, this
mainly helps to avoid generating some duplicated calls to vscale with
scalable vectors. It should also allow using EVL as induction increments
explicitly in D99750. Referring to VF * UF is also needed in other
places that we plan to migrate to VPlan, like the minimum trip count
check during skeleton creation.

The first version creates the value for VF * UF directly in
prepareToExecute to limit the scope of the patch. A follow-on patch will
model VF * UF computation explicitly in VPlan using recipes.

Moved from Phabricator (https://reviews.llvm.org/D157322)
2023-12-08 18:30:30 +00:00
Florian Hahn
633fe60149
[VPlan] Print flags for VPWidenCastRecipe.
Update VPWidenCastRecipe to also print flags. Simplify nneg printing
test and replace hard-coded value number references with patterns.
2023-12-08 10:48:54 +00:00
Florian Hahn
bbd1941a38
[VPlan] Add disjoint flag to VPRecipeWithIRFlags. (#74364)
A new disjoint flag was added for OR instructions in #72583. 

Update VPRecipeWithIRFlags to also support the new flag. This
allows printing and preserving the disjoint flag in vectorized code.
2023-12-05 15:21:59 +00:00
Alexey Bataev
056367bb19
[LV]Support dropping of nneg flag for zext widencast recipes. (#74112)
Compiler crashes when the assertion triggered for zext nneg instruction,
that checks that the instruction cannot produce poison. Changed the base
class for widencast recipe to handle dropping nneg flag to avoid
compiler crash.
2023-12-05 09:17:23 -05:00
Florian Hahn
d00c502ee5
[LV] Add tests for preserving and printing the new disjoint flag.
Tests for support for the disjoint flag added in #72583.
2023-12-04 20:12:11 +00:00
Florian Hahn
f7a8a78cb7
[VPlan] Also print operands of canonical IV (NFC).
Also print the operands of VPCanonicalIVPHIRecipe. That was missed
earlier.
2023-10-16 20:28:23 +01:00
Florian Hahn
38f8b7cbe4
[LV] Replace value numbers with patterns in tests (NFC).
Replace some hardcoded value numbers in CHECK-LINES to use patterns, to
 make the tests more robust wrt renumbering.
2023-10-16 19:53:44 +01:00
Florian Hahn
3fa1b254b7
[VPlan] Print blend recipe as operand directly, instead of IR PHI.
Update VPBlendRecipe::print() to print the result directly, instead of
relying on the stored Phi pointer. This brings the recipe in line with
how other recipes are printed.
2023-09-04 12:35:58 +01:00
Florian Hahn
af635a5547
[VPlan] Model wrap flags directly, remove *NUW opcodes (NFC)
Model wrap flags directly using VPRecipeWithIRFlags and clean up the
duplicated *NUW opcodes.

D157144 will build on this and also model FMFs for VPInstruction.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D157194
2023-08-08 12:12:30 +01:00
Florian Hahn
93c5bae00e
[VPlan] Use printOperands for VPInstruction.
Use the printOperands for printing VPInstruction's operands to be more
in line with other recipes and ensure consistent printing after D15719.

Also removes some stray spaces in print output.
2023-08-08 11:31:21 +01:00
Florian Hahn
299f0ff60e
[VPlan] Print IR flags for VPRecipeWithIRFlags.
Now that IR flags are modeled as part of VPRecipeWithIRFlags, include
the flags when printing recipes.

Depends on D150027.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D150029
2023-05-23 20:36:16 +01:00
Florian Hahn
6c35d423c8
[VPlan] Add tests to print exact and flags on calls (NFC).
Adds missing test coverage for D150029.
2023-05-16 21:18:31 +01:00
Florian Hahn
faa8f582b9
[VPlan] Add printing test with fast-math flags.
Add missing test coverage for D150029.
2023-05-09 22:43:03 +01:00
Florian Hahn
b85a402dd8
[VPlan] Introduce new entry block to VPlan for early SCEV expansion.
This patch adds a new preheader block the VPlan to place SCEV expansions
expansions like the trip count. This preheader block is disconnected
at the moment, as the bypass blocks of the skeleton are not yet modeled
in VPlan.

The preheader block is executed before skeleton creation, so the SCEV
expansion results can be used during skeleton creation. At the moment,
the trip count expression and induction steps are expanded in the new
preheader. The remainder of SCEV expansions will be moved gradually in
the future.

D147965 will update skeleton creation to use the steps expanded in the
pre-header to fix #58811.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D147964
2023-05-04 14:00:13 +01:00
Florian Hahn
b0e118bd77
[LV] Update tests checking VPlans to use patterns for VPValues.
This makes the tests more robust to changes in value numbering for
VPValues.
2023-04-09 20:32:09 +01:00
Florian Hahn
36d70a6aea
[VPlan] Remove redundant blocks by merging them into predecessors.
Add and run VPlan transform to fold blocks with a single predecessor
into the predecessor. This remove redundant blocks and addresses a TODO
to replace special handling for the vector latch VPBB.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D139927
2022-12-26 22:47:09 +00:00
Florian Hahn
cf8d8a33c6
[LV] Convert some tests to use opaque pointers (NFC). 2022-12-19 20:44:44 +00:00
Roman Lebedev
be51fa4580
[NFC] Port all runlines for LoopVectorize pass tests to -passes syntax 2022-12-05 22:17:30 +03:00
Florian Hahn
0c5df7cd2f
Recommit "[VPlan] Add VPDerivedIVRecipe, use for VPScalarIVStepsRecipe."
This reverts commit bf15f1e489aa2f1ac13268c9081a992a8963eb5b.

The updated version fixes a crash by checking the induction kind instead
of the opcode; for integer inductions, the step is always added, but the
opcode might not be set.
2022-11-30 17:04:20 +00:00
Florian Hahn
bf15f1e489
Revert "[VPlan] Add VPDerivedIVRecipe, use for VPScalarIVStepsRecipe."
This reverts commit 0fa666ecedc3f36471c0fee925d664512e7525a8.

This triggers an assertion during AArch64 stage2 builds. Revert while I
investigate.

See https://lab.llvm.org/buildbot/#/builders/179/builds/4967/steps/11/logs/stdio
2022-11-28 22:43:11 +00:00
Florian Hahn
0fa666eced
[VPlan] Add VPDerivedIVRecipe, use for VPScalarIVStepsRecipe.
This patch splits off the logic to transform the canonical IV to a
a value for an induction with a different start and step. This
transformation only needs to be done once (independent of VF/UF) and
enables sinking of VPScalarIVStepsRecipe as follow-up.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D133758
2022-11-28 16:32:31 +00:00
Florian Hahn
7eb4ec1c75
[VPlan] Print predicates for widened cmp instructions (NFC). 2022-10-21 08:54:11 +01:00
Philip Reames
4c4c0d2c06 [LV] Use safe-divisor lowering for fixed vectors if profitable
This extends the safe-divisor widening scheme recently added for scalable vectors to handle fixed vectors as well.

Differential Revision: https://reviews.llvm.org/D132591
2022-09-08 09:15:54 -07:00
Florian Hahn
a5bb4a3b4d
[VPlan] Replace CondBit with BranchOnCond VPInstruction.
This patch removes CondBit and Predicate from VPBasicBlock. To do so,
the patch introduces a new branch-on-cond VPInstruction opcode to model
a branch on a condition explicitly.

This addresses a long-standing TODO/FIXME that blocks shouldn't be users
of VPValues. Those extra users can cause issues for VPValue-based
analyses that don't expect blocks. Addressing this fixme should allow us
to re-introduce 266ea446ab7476.

The generic branch opcode can also be used in follow-up patches.

Depends on D123005.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D126618
2022-06-03 11:48:31 +01:00
Florian Hahn
3bebec6592
[VPlan] Model first exit values using VPLiveOut.
This patch introduces a new VPLiveOut subclass of VPUser  to model
 exit values explicitly. The initial version handles exit values that
are neither part of induction or reduction chains nor first order
recurrence phis.

Fixes #51366, #54867, #55167, #55459

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D123537
2022-05-21 16:01:38 +01:00
Florian Hahn
ff8d0b338f
[VPlan] Add test for printing plan with an exit value.
Test for printing plan with additions from D123537.
2022-05-04 17:19:02 +01:00
Igor Kirillov
4e5e042d9a [LoopVectorize] Support reductions that store intermediary result
Adds ability to vectorize loops containing a store to a loop-invariant
address as part of a reduction that isn't converted to SSA form due to
lack of aliasing info. Runtime checks are generated to ensure the store
does not alias any other accesses in the loop.

Ordered fadd reductions are not yet supported.

Differential Revision: https://reviews.llvm.org/D110235
2022-05-03 10:12:30 +01:00
Florian Hahn
bea69b232f
[VPlan] Initial modeling of middle block in VPlan.
This patch extends the scope of VPlan to also include the exit (aka
middle) block.

For now, the exit block remains empty, but handling of exit values will
subsequently be moved to VPlan, by adding recipes to model exit values
in the exit block.

As a first step, this will allow fixing #51366.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D123457
2022-04-20 19:34:41 +01:00
Florian Hahn
a65f2730d2
[VPlan] Expand induction step in VPlan pre-header.
This patch moves SCEV expansion of steps used by
VPWidenIntOrFpInductionRecipes to the pre-header using
VPExpandSCEVRecipe. This ensures that those steps are expanded while the
CFG is in a valid state. Previously, SCEV expansion may happen during
vector body code-generation, during which the CFG may be invalid,
causing issues with SCEV expansion.

Depends on D122095.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D122096
2022-04-19 13:06:39 +02:00
Florian Hahn
5f1eb74850
[VPlan] Place VPExpandSCEVRecipe in pre-header.
After D121624 models the pre-header in VPlan, VPExpandSCEVRecipes can be
placed there. This ensures SCEV expansion happens before modifying the
CFG during VPlan execution, when CFG is incomplete.

Depends on D121624.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D122095
2022-04-10 10:26:20 +02:00
Florian Hahn
256c6b0ba1
[VPlan] Model pre-header explicitly.
This patch extends the scope of VPlan to also model the pre-header.
The pre-header can be used to place recipes that should be code-gen'd
outside the loop, like SCEV expansion.

Depends on D121623.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D121624
2022-04-09 14:19:47 +02:00
Florian Hahn
95b2aa511e
[VPlan] Set VPlan header block name to vector.body.
This brings the VPlan block naming in line with the naming of the
generated basic blocks.
2022-04-02 19:34:32 +01:00
Florian Hahn
973183612e
[VPlan] Add test for VPExpandSCEVRecipe printing. 2022-03-20 10:11:40 +00:00
Florian Hahn
d5fbcf76fd
[VPlan] Improve pattern in vplan-printing.ll check line.
The existing pattern only matched a single value, which breaks if the
numbering slightly changes.
2022-03-19 16:03:25 +00:00
Florian Hahn
95f76bff1c
[LV] Create & use VPScalarIVSteps for all scalar users.
This patch is a follow-up to D115953. It updates optimizeInductions
to also introduce new VPScalarIVStepsRecipes if an IV has both vector
and scalar uses.

It updates all uses that only need scalar values to use the newly
created recipe for the scalar steps.

This completes untangling of VPWidenIntOrFpInductionRecipe
code-generation. Now the recipe *only* creates the widened vector
values, as it says on the tin.

The code to genereate IR has been moved directly to
VPWidenIntOrFpInductionRecipe::execute.

Note that the recipe has been updated to hold a reference to
ScalarEvolution, which is needed to expand the step, until we can place
the corresponding SCEV expansion in the pre-header.

Depends on D120827.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D120828
2022-03-13 17:15:24 +00:00
Roman Lebedev
2f80ea7f4f
[NFC][LV] Use different braces in debug output
The analysis passes output function name encapsulated in `'` braces,
but LV uses `"`. Harmonizing this may help in creating an update script
for the LV costmodel test checks.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D121105
2022-03-07 19:32:37 +03:00
Florian Hahn
8777cb66a8
[VPlan] Remove reliance on underlying instr for ScalarIVSteps (NFCI).
Instead of relying on underlying instructions, this patch updates
VPScalarIVStepsRecipe to only store the required type information.

This removes access to unrelated information, as well as avoiding issues
with the same underlying instruction being shared by multiple recipes.

This change should only change the debug output and not cause any
codegen changes, hence NFCI.
2022-03-02 16:23:19 +00:00
Florian Hahn
b3e8ace198
Recommit "[VPlan] Introduce recipe to build scalar steps."
This reverts the revert commit ff93260bf6bddfbad1fa65c4d5184988885b900f.

The underlying issue causing the PPC bot failures has been fixed in
cbaac1473403 and a corresponding test case has been added in
ad2cad1c521c.

Original message:

    This patch adds a new VPScalarIVStepsRecipe to handle building scalar
    steps.

    In the first patch, it only handles the case where there is no vector
    induction variable needed.

    Reviewed By: Ayal

    Differential Revision: https://reviews.llvm.org/D115953
2022-02-28 14:12:20 +00:00
Florian Hahn
ff93260bf6
Revert "[VPlan] Introduce recipe to build scalar steps."
This reverts commit 49b23f451cf713036c99573a35daed308d2ac894.

This appears to break some PPC build bots. Revert while I investigate.
2022-02-27 17:51:19 +00:00
Florian Hahn
49b23f451c
[VPlan] Introduce recipe to build scalar steps.
This patch adds a new VPScalarIVStepsRecipe to handle building scalar
steps.

In the first patch, it only handles the case where there is no vector
induction variable needed.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D115953
2022-02-27 17:32:41 +00:00
Florian Hahn
da740492b0
[VPlan] Remove dead header-phi recipes.
This patch adds a new transform to remove dead recipes. For now, it only
removes dead recipes in the header, to keep the number tests that require
updating manageable. Future patches will extend this to remove dead
recipes across the whole plan.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D118051
2022-02-26 16:26:39 +00:00
Florian Hahn
d4a8fc3a87
[VPlan] Introduce and use BranchOnCount VPInstruction.
This patch adds a new BranchOnCount VPInstruction opcode with 2
operands. It first compares its 2 operands (increment of canonical
induction and vector trip count), followed by a branch to either the
exit block or back to the vector header.

It must be the last recipe in the exit block of the topmost vector loop
region.

This extracts parts from D113224 and was discussed in D113223.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D116479
2022-01-12 13:42:13 +00:00
Florian Hahn
65c4d6191f
[VPlan] Add VPCanonicalIVPHIRecipe, partly retire createInductionVariable.
At the moment, the primary induction variable for the vector loop is
created as part of the skeleton creation. This is tied to creating the
vector loop latch outside of VPlan. This prevents from modeling the
*whole* vector loop in VPlan, which in turn is required to model
preheader and exit blocks in VPlan as well.

This patch introduces a new recipe VPCanonicalIVPHIRecipe to represent the
primary IV in VPlan and CanonicalIVIncrement{NUW} opcodes for
VPInstruction to model the increment.

This allows us to partly retire createInductionVariable. At the moment,
a bit of patching up is done after executing all blocks in the plan.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D113223
2022-01-05 10:46:06 +00:00
Florian Hahn
5b362e4c7f
[VPlan] Add Debugloc to VPInstruction.
Upcoming changes require attaching debug locations to VPInstructions,
e.g. adding induction increment recipes in D113223.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D115123
2021-12-20 15:10:41 +00:00
Florian Hahn
e2885c7c9b
[VPlan] Add printing test with VPInstruction with debug locs.
Test case for D113223.
2021-12-13 13:08:41 +00:00
Florian Hahn
a7648eb2aa
[LV] Use patterns in some induction tests, to make more robust. (NFC) 2021-11-24 13:32:24 +00:00