112 Commits

Author SHA1 Message Date
Florian Hahn
ff0ec4f42e
Recommit "[VPlan] Unify Value2VPValue and VPExternalDefs maps (NFCI)."
This reverts the revert commit 8c2276f89887d0a27298a1bbbd2181fa54bbb509.

The updated patch re-orders the getDefiningRecipe check in getVPalue to avoid
a use-after-free.

Original commit message:

    Before this patch, a VPlan contained 2 mappings for Values -> VPValue:
    1) Value2VPValue and 2) VPExternalDefs.

    This duplication is unnecessary and there are already cases where
    external defs are added to Value2VPValue. This patch replaces all uses
    of VPExternalDefs with Value2VPValue.

    It clarifies the naming of getOrAddVPValue (to getOrAddExternalVPValue)
    and addVPValue (to addExternalVPValue).

    At the moment, this is NFC, but will enable additional simplifications
    in D147783.

    Depends on D147891.

    Reviewed By: Ayal

    Differential Revision: https://reviews.llvm.org/D147892
2023-04-18 10:29:31 +01:00
Vitaly Buka
8c2276f898 Revert "[VPlan] Unify Value2VPValue and VPExternalDefs maps (NFCI)."
Asan detects heap-use-after-free, see D147892.

This reverts commit 4fc190351e5af901b6107d162d07e1fbca90934f.
This reverts commit 668045eb77628be13e448ffbb855473ffca1cc43.
2023-04-17 17:24:10 -07:00
Manoj Gupta
3d8ed8b519 Revert "[VPlan] Switch to checking sinking legality for recurrences in VPlan."
This reverts commit 7fc0b3049df532fce726d1ff6869a9f6e3183780.

Causes a clang hang when building xz utils, github issue #62187.
2023-04-17 12:19:36 -07:00
Florian Hahn
4fc190351e
[VPlan] Remove uneeded NeedsVectorIV from VPWidenIntOrFpInduction.
After recent improvements, all instances of
VPWidenIntOrFpInductionRecipe should needs a vector IV and there's no
need for a separate field.
2023-04-17 13:38:00 +01:00
Florian Hahn
668045eb77
[VPlan] Unify Value2VPValue and VPExternalDefs maps (NFCI).
Before this patch, a VPlan contained 2 mappings for Values -> VPValue:
1) Value2VPValue and 2) VPExternalDefs.

This duplication is unnecessary and there are already cases where
external defs are added to Value2VPValue. This patch replaces all uses
of VPExternalDefs with Value2VPValue.

It clarifies the naming of getOrAddVPValue (to getOrAddExternalVPValue)
and addVPValue (to addExternalVPValue).

At the moment, this is NFC, but will enable additional simplifications
in D147783.

Depends on D147891.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D147892
2023-04-16 15:38:31 +01:00
Florian Hahn
2db031528e
[VPlan] Check VPValue step in isCanonical (NFCI).
Update the isCanonical() implementations to check the VPValue step
operand instead of the step in the induction descriptor.

At the moment this is NFC, but it enables further optimizations if the
step is replaced by a constant in D147783.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D147891
2023-04-16 14:48:03 +01:00
Florian Hahn
7fc0b3049d
[VPlan] Switch to checking sinking legality for recurrences in VPlan.
Building on D142885 and D142589, retire the SinkAfter map from the
recurrence handling code. It is replaced by checking whether it is
possible to sink all users of a recurrence directly in VPlan. This
results in simpler code overall and allows to handle additional cases
(see the improvements in @test_crash).

Depends on D142885.
Depends on D142589.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D142886
2023-04-13 22:00:52 +01:00
Jie Fu
ae5f049378 [Transforms] Fix -Wunused-function for 'GetReplicateRegion' with -DLLVM_ENABLE_ASSERTIONS=OFF (NFC)
/Users/jiefu/llvm-project/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp:614:23: error: unused function 'GetReplicateRegion' [-Werror,-Wunused-function]
static VPRegionBlock *GetReplicateRegion(VPRecipeBase *R) {
                      ^
1 error generated.
2023-04-05 22:34:42 +08:00
Florian Hahn
c18bc7f7fe
[VPlan] Replace check for replicate regions with assert (NFCI).
After recent changes, replication regions only get introduced later, so
there's no need to check for them.
2023-04-05 14:29:24 +01:00
Florian Hahn
371bb2c9d3
[VPlan] Move createReplicateRegion out of VPRecipeBuilder.h. (NFC)
The function doesn't use anything from VPRecipeBuilder, so move the
definition to where it is actually used and turn it into a simple static
function.

It also makes the VPRecipeBuilder argument for createAndOptimizeReplicateRegions
unnecessary.
2023-03-18 20:30:49 +00:00
Florian Hahn
eca14a810e
[VPlan] Consolidate replicate region optimizations (NFC).
As suggested in D143865, consolidate replicate region creation and
optimization in a single helper that's exposed and used by LV.
2023-03-16 17:06:44 +00:00
Florian Hahn
54558fd8f3
[VPlan] Replace InvariantCond field from VPWidenSelectRecipe.
There is no need to store information about invariance in the recipe.
Replace the fields with checks of the operands using
isDefinedOutsideVectorRegions.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D144489
2023-03-10 15:28:43 +01:00
Florian Hahn
a8adb38a96
[VPlan] Replace invariance fields from VPWidenGEPRecipe.
There is no need to store information about invariance in the recipe.
Replace the fields with checks of the operands using
isDefinedOutsideVectorRegions.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D144487
2023-03-09 17:52:22 +01:00
Florian Hahn
79272ec028
[VPlan] Add predicate to VPReplicateRecipe, expand region later.
This patch adds the predicate as additional operand to VPReplicateRecipe
during initial construction. The predicated recipes are later moved into
replicate regions. This simplifies constructions and some VPlan
transformations, like fixed-order recurrence handling.

It also improves codegen in some cases (e.g. for in-loop reductions),
because the recipes remain in the same block.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D143865
2023-03-08 20:11:28 +01:00
Florian Hahn
7737c05696
[VPlan] Make sure properlyDominates(A, A) returns false.
At the moment, properlyDominates(A, A) can return true via
LocalComesBefore. Add an early exit to ensure it returns false if
A == B.

Note: no test has been added because the existing test suite covers this
case already with libc++ with assertions enabled.

Fixes https://github.com/llvm/llvm-project/issues/60850.
2023-02-19 18:01:16 +00:00
Florian Hahn
807d43239a
[VPlan] Use properlyDominates predicate for ordering FOR users.
The current implementation may return true for A < B and B < A, which
may cause issues if the sort implementation assures this property of the
comperator. This should fix a crash with MSVC.
2023-02-13 21:24:58 +00:00
Florian Hahn
af3c25dc3d
[VPlan] Fix iterator invalidation in adjustFixedOrderRecurrences.
adjustFixedOrderRecurrences may insert instructions after immediately
after the PHI nodes in the block. This invalidates the phis() iterator.
To avoid crashing/accessing invalid recipes, first collect all
first-order recurrence phi recipes.

This should fix a crash reported by @dmgreen after D142589 landed.
2023-02-13 13:51:14 +00:00
Florian Hahn
c83fdc905a
[LV] Perform recurrence sinking directly on VPlan.
This patch updates LV to sink recipes directly using the VPlan use
chains. The initial patch only moves sinking to be purely VPlan-based.
Follow-up patches will move legality checks to VPlan as well.

At the moment, there's a single test failure remaining.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D142589
2023-02-08 15:49:29 +00:00
Florian Hahn
fb40c34b8f
[VPlan] Consider all recipes in replicate blocks as sink candidates.
Update sinkScalarOperands to consider all operands of recipes in
replicate blocks as sink candidates This enables additional sinking
opportunities and is another step towards retiring LLVM IR-based
sinkScalarOperands.

This enables iterative sinking of operands for successive calls of
sinkScalarOperands.

Depends on D139788.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D139790
2023-01-21 17:14:13 +00:00
Florian Hahn
e2c43a547b
[VPlan] Add vp_depth_first_deep (NFC)
Similar to vp_depth_first_shallow (D140512) add vp_depth_first_deep to
make existing code clearer and more compact.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D142055
2023-01-19 20:34:23 +00:00
Florian Hahn
2b054d5dd4
[VPlan] Use to_vector when iterating over a temporary vector. (NFC) 2023-01-13 17:51:00 +00:00
Florian Hahn
78914e8c32
[VPlan] Keep entries in worklist in sinkScalarOperands.
Not removing the entries ensures that duplicates are avoided,
reducing the number of iterations.
2023-01-08 15:52:57 +00:00
Augie Fackler
0676156f81 Revert "[VPlan] Also consider operands of sink candidates in same block."
This reverts commit aa2414729ebbcb2d8f162e9002a3a6aa768b1f9d.

Previously-valid IR from a tensorflow test case (as shown on the
Diffusion revision for aa2414729ebbcb2d8f162e9002a3a6aa768b1f9d) started
hanging in the loop-vectorize pass. Reverting to keep everyone working.
2023-01-04 16:17:13 -05:00
Florian Hahn
89718815c6
[VPlan] Adjust mergeReplicateRegions to be in line with mergeBlock (NFC)
Adjust mergeReplicateRegions to be in line with
mergeBlocksIntoPredecessors added in 36d70a6aea6b by collecting only the
valid candidates first.

Also rename to mergeReplicateRegionsIntoSuccessors and add missing
doc-comment.

This addresses post-commit suggestions by @Ayal.
2023-01-01 19:48:49 +00:00
Florian Hahn
cd16a3f04c
[VPlan] Move GraphTraits definitions to separate header (NFC).
This reduces the size of VPlan.h and avoids future growth of the file
when the graph traits are extended in future patches.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D140500
2022-12-31 15:14:57 +00:00
Florian Hahn
aa2414729e
[VPlan] Also consider operands of sink candidates in same block.
Even if the the sink candidate is already in the target block, its
operands can be candidates for sinking. Queue them up as well. Also
moves the queuing logic to a helper.
2022-12-30 18:24:35 +00:00
Florian Hahn
e91e62db14
[LV] Sink scalar operands and merge regions repeatedly.
Merging regions can enable new sinking opportunities (e.g. if users of a
scalar value are moved from different VPBBs into the same VPBB). Sinking
in turn can also enable new merging opportunities (e.g. if a recipe
between to merge-able regions is moved.

To enable more sinking opportunities, repeat sinking & merging if
regions could be merged.

Also fix mergeReplicateRegions to return the correct Changed status.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D139788
2022-12-27 18:08:32 +00:00
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
435e220ba6
[VPlan] Use VPBB in sinkScalarOperands directly. (NFC)
Suggested by @Ayal in D139790.
2022-12-25 21:34:59 +00:00
Florian Hahn
9758242046
[LV] Use SCEV to check if the trip count <= VF * UF.
Just comparing constant trip counts causes LV to miss cases where the
vector loop body only executes once.

The motivation for this is to remove the need for unrolling to remove
vector loop back-edges, if the body only executes once in more cases.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D133017
2022-12-24 18:34:54 +00:00
Florian Hahn
e1650c8d52
[LV] Move exit cond simplification to separate transform.
This sets the stage for D133017 by moving out the code that performs
VPlan based simplifications to a separate transform that takes the
chosen VF & UF as arguments.

The main advantage is that this transform runs before any changes to
the CFG are being made. This allows using SCEV without worrying about
making queries while the IR is in an incomplete state.

Note that this patch switches the reasoning to use SCEV, but still only
simplifies loops with constant trip counts. Using SCEV here is needed to
access the backedge taken count, because the trip count IR value has not
been created yet.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D135017
2022-12-23 12:51:21 +00:00
Florian Hahn
e898479f2b
[VPlan] Sink non-uniform recieps for scalar plans.
In scalar plans, replicate recipes will only generate a single value per
UF, independent of whether they are uniform or not. So don't consider
uniformity for plans with scalar VFs only.

This allows us to handle a few additional cases in VPlan sinking instead
of non-VPlan sinkScalarOperands.

Depends on D133762.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D134218
2022-12-14 17:55:31 +00:00
Florian Hahn
37809c867a
[VPlan] Support sinking VPScalarIVStepsRecipe.
This patch extends VP-based sinking to also sink VPScalarStepsRecipe.
This takes us a step closer towards retiring the IR based sinking.

The main change is extending VPScalarIVStepsRecipe::execute to support
executing in a replicate-region.

Depends on D133758.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D133760
2022-12-04 22:59:17 +00:00
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
12bb5535d2
[VPlan] Move cast codegen to emitTransformedIndex (NFCI).
This reduces duplication a bit.

Suggested as simplification in D133758.
2022-11-26 22:47:13 +00:00
Florian Hahn
43f0f1a66f
[VPlan] Use onlyFirstLaneUsed in sinkScalarOperands.
Replace custom code to check if only the first lane is used by generic
helper `onlyFirstLaneUsed`. This enables VPlan-based sinking in a few
additional cases and was suggested in D133760.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D136368
2022-10-29 19:45:19 +01:00
Florian Hahn
fc444ddc77
[VPlan] Add field to track if intrinsic should be used for call. (NFC)
This patch moves the cost-based decision whether to use an intrinsic or
library call to the point where the recipe is created. This untangles
code-gen from the cost model and also avoids doing some extra work as
the information is already computed at construction.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D132585
2022-09-01 13:14:40 +01:00
Florian Hahn
24b5f8e0d0
[VPlan] Make sure optimizeInductions removes wide ind from scalar plan.
In some cases, there may be widened users of inductions even though the
plan includes the scalar VF. In those cases, make sure we still replace
the VPWidenIntOrFpInductionRecipe with scalar steps, as otherwise we may
try to execute a VPWidenIntOrFpInductionRecipe with a scalar VF.

Alternatively the patch could also split the range if needed.

This fixes a crash exposed by D123720.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D128755
2022-06-30 09:11:48 +01:00
Florian Hahn
569d84fe99
[VPlan] Remove dead recipes across whole plan.
This extends removeDeadRecipe to remove recipes across the whole plan.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D127580
2022-06-23 13:36:02 +02:00
Florian Hahn
763f2bdba5
[VPlan] Remove dead OrigLoop argument from removeDeadRecipes (NFC).
The use of the argument has been remove a while ago. Remove the dead
argument.
2022-06-11 23:36:47 +01:00
Florian Hahn
85983ca42e
[VPlan] Replace remaining use of needsScalarIV.
All information is already available in VPlan. Note that there are some
test changes, because we now can correctly look through instructions
like truncates to analyze the actual users.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D123541
2022-06-09 12:05:37 +01:00
Florian Hahn
cedfd7a2e5
Recommit "[VPlan] Remove uneeded needsVectorIV check."
This reverts commit 266ea446ab747671eb6c736569c3c9c5f3c53d11.

The reasons for the revert have been addressed by cleaning up condition
handling in VPlan and properly marking VPBranchOnMaskRecipe as using
scalars.

The test case for the revert from D123720 has been added in 3d663308a5d.
2022-06-08 14:06:45 +01:00
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
05776122b6
[VPlan] Use region for each loop in native path.
This patch updates the VPlan native path to use VPRegionBlocks for all
loops in a loop nest. Up to now, only the outermost loop used a region.

This is a step towards unifying both paths and keep things consistent
between them. It also prepares various code-gen parts for modeling the
pre-header in the inner loop vectorizer (D121624).

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D123005
2022-06-01 10:41:05 +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
c1a9d14982
[VPlan] Move usesScalars/onlyFirstLaneUsed to VPUser.
Those helpers model properties of a user and they should also be
available to non-recipe users. This will be used in D123537 for a new
exit value user.

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D124936
2022-05-17 11:20:06 +01:00
Florian Hahn
266ea446ab
Revert "Recommit "[VPlan] Remove uneeded needsVectorIV check.""
This reverts commit 8b48223447311af8b3022697dd58858e1ce6975f.

This triggers an assertion on a test case mentioned in D123720.
Revert while I investigate.
2022-05-09 20:33:14 +01:00
Florian Hahn
8b48223447
Recommit "[VPlan] Remove uneeded needsVectorIV check."
This reverts commit f4e1eaa3755a13f85696be3b74b387122b74a558.

The patch was originally reverted because it uncovered an issue that has
now been fixed in 0ef8ca6d88aa7e4abc.
2022-05-04 10:53:42 +01:00