Commit Graph

848 Commits

Author SHA1 Message Date
Alexey Bataev af870e11ae [SLP] Add detection of shuffled/perfect matching of tree entries.
SLP supports perfect diamond matching for the vectorized tree entries
but do not support it for gathered entries and does not support
non-perfect (shuffled) matching with 1 or 2 tree entries. Patch adds
support for this matching to improve cost of the vectorized tree.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D100495
2021-04-20 09:08:46 -07:00
Alexey Bataev b82344a019 Revert "[SLP] Add detection of shuffled/perfect matching of tree entries."
This reverts commit daf6e18c55 to fix the
compiler crash.
2021-04-20 08:29:32 -07:00
Alexey Bataev daf6e18c55 [SLP] Add detection of shuffled/perfect matching of tree entries.
SLP supports perfect diamond matching for the vectorized tree entries
but do not support it for gathered entries and does not support
non-perfect (shuffled) matching with 1 or 2 tree entries. Patch adds
support for this matching to improve cost of the vectorized tree.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D100495
2021-04-20 07:46:49 -07:00
Alexey Bataev cf00cb8bed Revert "[SLP] Add detection of shuffled/perfect matching of tree entries."
This reverts commit b232771aca to fix
buildbots.
2021-04-20 07:16:11 -07:00
Alexey Bataev b232771aca [SLP] Add detection of shuffled/perfect matching of tree entries.
SLP supports perfect diamond matching for the vectorized tree entries
but do not support it for gathered entries and does not support
non-perfect (shuffled) matching with 1 or 2 tree entries. Patch adds
support for this matching to improve cost of the vectorized tree.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D100495
2021-04-20 06:55:55 -07:00
Alexey Bataev 8030481065 Revert "[SLP]Add detection of shuffled/perfect matching of tree entries."
This reverts commit d6fde91379 to fix
compiler crashes.
2021-04-19 14:10:04 -07:00
Alexey Bataev d6fde91379 [SLP]Add detection of shuffled/perfect matching of tree entries.
SLP supports perfect diamond matching for the vectorized tree entries
but do not support it for gathered entries and does not support
non-perfect (shuffled) matching with 1 or 2 tree entries. Patch adds
support for this matching to improve cost of the vectorized tree.

Differential Revision: https://reviews.llvm.org/D100495
2021-04-19 13:29:30 -07:00
Simon Pilgrim b49c41afba [SLP] createOp - fix null dereference warning. NFCI.
Only attempt to propagateIRFlags if we have both SelectInst - afaict we shouldn't have matched a min/max reduction without both SelectInst, but static analyzer doesn't know that.
2021-04-14 15:24:41 +01:00
dfukalov d066079728 [NFC][AA] Prepare to convert AliasResult to class with PartialAlias offset.
Main reason is preparation to transform AliasResult to class that contains
offset for PartialAlias case.

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D98027
2021-04-09 12:54:22 +03:00
Alexey Bataev ab124bbe2a [SLP]Fix PR49898: Infinite loop in SLP vectorizer.
We should not re-try attempt of finding of the consecutive store chain
if it was tried before.

Differential Revision: https://reviews.llvm.org/D100131
2021-04-08 14:18:06 -07:00
Alexey Bataev a78e86e6be [SLP]Avoid multiple attempts to vectorize CmpInsts.
No need to lookup through and/or try to vectorize operands of the
CmpInst instructions during attempts to find/vectorize min/max
reductions. Compiler implements postanalysis of the CmpInsts so we can
skip extra attempts in tryToVectorizeHorReductionOrInstOperands and save
compile time.

Differential Revision: https://reviews.llvm.org/D99950
2021-04-07 06:15:42 -07:00
Alexey Bataev 00a84f9a7f [SLP]Improve vectorization of the CmpInst instructions.
During vectorization better to postpone the vectorization of the CmpInst
instructions till the end of the basic block. Otherwise we may vectorize
it too early and may miss some vectorization patterns, like reductions.

Reworked part of D57059

Differential Revision: https://reviews.llvm.org/D99796
2021-04-05 06:22:51 -07:00
Fangrui Song 8e5f3d04f2 [SLPVectorizer] Fix divide-by-zero after D99719
Will add a test case later.
2021-04-02 11:13:51 -07:00
Alexey Bataev 5fcb07a070 [SLP]Fix a bug in min/max reduction, number of condition uses.
The ultimate reduction node may have multiple uses, but if the ultimate
reduction is min/max reduction and based on SelectInstruction, the
condition of this select instruction must have only single use.

Differential Revision: https://reviews.llvm.org/D99753
2021-04-02 07:09:44 -07:00
Florian Hahn 0f3230390b
[SLP] Better estimate cost of no-op extracts on target vectors.
The motivation for this patch is to better estimate the cost of
extracelement instructions in cases were they are going to be free,
because the source vector can be used directly.

A simple example is

    %v1.lane.0 = extractelement <2 x double> %v.1, i32 0
    %v1.lane.1 = extractelement <2 x double> %v.1, i32 1

    %a.lane.0 = fmul double %v1.lane.0, %x
    %a.lane.1 = fmul double %v1.lane.1, %y

Currently we only consider the extracts free, if there are no other
users.

In this particular case, on AArch64 which can fit <2 x double> in a
vector register, the extracts should be free, independently of other
users, because the source vector of the extracts will be in a vector
register directly, so it should be free to use the vector directly.

The SLP vectorized version of noop_extracts_9_lanes is 30%-50% faster on
certain AArch64 CPUs.

It looks like this does not impact any code in
SPEC2000/SPEC2006/MultiSource both on X86 and AArch64 with -O3 -flto.

This originally regressed after D80773, so if there's a better
alternative to explore, I'd be more than happy to do that.

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D99719
2021-04-02 10:40:12 +01:00
Alexey Bataev c03696da5e [SLP]Improve and fix getVectorElementSize.
1. Need to cleanup InstrElementSize map for each new tree, otherwise might
use sizes from the previous run of the vectorization attempt.
2. No need to include into analysis the instructions from the different basic
   blocks to save compile time.

Differential Revision: https://reviews.llvm.org/D99677
2021-04-01 06:51:26 -07:00
Alexey Bataev ce98a0556a [SLP]Remove `else` after `return`, NFC.` 2021-04-01 05:33:01 -07:00
Sanjay Patel da381cf7ce [SLP] allow matching integer min/max intrinsics as reduction ops
This is a 2nd try of:
3c8473ba53
which was reverted at:
 a26312f9d4
because of crashing.

This version includes extra code and tests to avoid the known
crashing examples as discussed in PR49730.

Original commit message:
As noted in D98152, we need to patch SLP to avoid regressions when
we start canonicalizing to integer min/max intrinsics.
Most of the real work to make this possible was in:
7202f47508

Differential Revision: https://reviews.llvm.org/D98981
2021-03-29 09:38:18 -04:00
Sanjay Patel b0797e0c12 [SLP] use dyn_cast instead of isa + cast; NFC 2021-03-26 13:52:31 -04:00
Sanjay Patel a26312f9d4 Revert "[SLP] allow matching integer min/max intrinsics as reduction ops"
This reverts commit 3c8473ba53 and includes test diffs to
maintain testing status.

There's at least 1 place that was not updated with 7202f47508 ,
so we can crash mismatching select and intrinsics as shown in
PR49730.
2021-03-26 09:59:14 -04:00
Yevgeny Rouban f7ef26ef0b [SLP] Fix crash in reduction for integer min/max
The SCEV commit b46c085d2b [NFCI] SCEVExpander:
    emit intrinsics for integral {u,s}{min,max} SCEV expressions
seems to reveal a new crash in SLPVectorizer.
SLP crashes expecting a SelectInst as an externally used value
but umin() call is found.

The patch relaxes the assumption to make the IR flag propagation safe.

Reviewed By: spatel

Differential Revision: https://reviews.llvm.org/D99328
2021-03-25 21:44:21 +07:00
Alexey Bataev 568c874117 [SLP]Improve and simplify extendSchedulingRegion.
We do not need to scan further if the upper end or lower end of the
basic block is reached already and the instruction is not found. It
means that the instruction is definitely in the lower part of basic
block or in the upper block relatively.
This should improve compile time for the very big basic blocks.

Differential Revision: https://reviews.llvm.org/D99266
2021-03-25 05:31:58 -07:00
Sander de Smalen 55d18b3cc2 [TTI] Return a TypeSize from getRegisterBitWidth.
This patch changes the interface to take a RegisterKind, to indicate
whether the register bitwidth of a scalar register, fixed-width vector
register, or scalable vector register must be returned.

Reviewed By: paulwalker-arm

Differential Revision: https://reviews.llvm.org/D98874
2021-03-24 14:45:13 +00:00
Alexey Bataev 99203f2004 [Analysis]Add getPointersDiff function to improve compile time.
Added getPointersDiff function to LoopAccessAnalysis and used it instead
direct calculatoin of the distance between pointers and/or
isConsecutiveAccess function in SLP vectorizer to improve compile time
and detection of stores consecutive chains.

Part of D57059

Differential Revision: https://reviews.llvm.org/D98967
2021-03-23 14:25:36 -07:00
Alexey Bataev f1b47ad278 Revert "[Analysis]Add getPointersDiff function to improve compile time."
This reverts commit 065a14a12d to
investigate and fix crash in SLP vectorizer.
2021-03-23 13:17:54 -07:00
Alexey Bataev 065a14a12d [Analysis]Add getPointersDiff function to improve compile time.
Added getPointersDiff function to LoopAccessAnalysis and used it instead
direct calculatoin of the distance between pointers and/or
isConsecutiveAccess function in SLP vectorizer to improve compile time
and detection of stores consecutive chains.

Part of D57059

Differential Revision: https://reviews.llvm.org/D98967
2021-03-23 12:58:42 -07:00
Sanjay Patel 3c8473ba53 [SLP] allow matching integer min/max intrinsics as reduction ops
As noted in D98152, we need to patch SLP to avoid regressions when
we start canonicalizing to integer min/max intrinsics.
Most of the real work to make this possible was in:
7202f47508

Differential Revision: https://reviews.llvm.org/D98981
2021-03-23 08:56:44 -04:00
Bjorn Pettersson 688cdddafb [SLP] Honor min/max regsize and min/max VF in vectorizeStores
Make sure we use PowerOf2Floor instead of PowerOf2Ceil when
calculating max number of elements that fits inside a vector
register (otherwise we could end up creating vectors larger
than the maximum vector register size).

Also make sure we honor the min/max VF (as given by TTI or
cmd line parameters) when doing vectorizeStores.

Reviewed By: anton-afanasyev

Differential Revision: https://reviews.llvm.org/D97691
2021-03-22 17:29:35 +01:00
Alexey Bataev b3ced9852c [SLP]Fix crash on extending scheduling region.
If SLP vectorizer tries to extend the scheduling region and runs out of
the budget too early, but still extends the region to the new ending
instructions (i.e., it was able to extend the region for the first
instruction in the bundle, but not for the second), the compiler need to
recalculate dependecies in full, just like if the extending was
successfull. Without it, the schedule data chunks may end up with the
wrong number of (unscheduled) dependecies and it may end up with the
incorrect function, where the vectorized instruction does not dominate
on the extractelement instruction.

Differential Revision: https://reviews.llvm.org/D98531
2021-03-18 06:11:08 -07:00
David Green e2935dcfc4 [TTI] Add a Mask to getShuffleCost
This adds an Mask ArrayRef to getShuffleCost, so that if an exact mask
can be provided a more accurate cost can be provided by the backend.
For example VREV costs could be returned by the ARM backend. This should
be an NFC until then, laying the groundwork for that to be added.

Differential Revision: https://reviews.llvm.org/D98206
2021-03-17 17:46:26 +00:00
Bu Le 9abe500473 [SLP] Fix the trunc instruction insertion problem
Current SLP pass has this piece of code that inserts a trunc instruction
after the vectorized instruction. In the case that the vectorized instruction
is a phi node and not the last phi node in the BB, the trunc instruction
will be inserted between two phi nodes, which will trigger verify problem
in debug version or unpredictable error in another pass.
This patch changes the algorithm to 'if the last vectorized instruction
is a phi, insert it after the last phi node in current BB' to fix this problem.
2021-03-17 13:51:08 +03:00
Sanjay Patel 7202f47508 [SLP] separate min/max matching from its instruction-level implementation; NFC
The motivation is to handle integer min/max reductions independently
of whether they are in the current cmp+sel form or the planned intrinsic
form.

We assumed that min/max included a select instruction, but we can
decouple that implementation detail by checking the instructions
themselves rather than relying on the recurrence (reduction) type.
2021-03-16 17:16:11 -04:00
Sanjay Patel 40fdb43d30 [SLP] improve readability in reduction logic; NFC
We had 2 different and ambiguously-named 'I' variables.
2021-03-16 07:35:13 -04:00
Valery N Dmitriev 73f94969b2 [SLP] Fix crash when matching associative reduction for integer min/max.
Associative reduction matcher in SLP begins with select instruction but when
it reached call to llvm.umax (or alike) via def-use chain the latter also matched
as UMax kind. The routine's later code assumes matched instruction to be a select
and thus it merely died on the first encountered cast that did not fit.

Differential Revision: https://reviews.llvm.org/D98432
2021-03-11 11:52:57 -08:00
Sanjay Patel 23fd647cc6 [SLP] remove dead null check; NFC
We cast<> to Instruction (not dyn_cast<>), so we already
required/assumed that Cmp is not null.
2021-03-09 17:43:07 -05:00
Alexey Bataev a054e94e9e [SLP]Merge reorder and reuse shuffles.
It is possible to merge reuse and reorder shuffles and reduce the total
cost of the vectorization tree/number of final instructions.

Differential Revision: https://reviews.llvm.org/D94992
2021-03-02 06:39:47 -08:00
David Green bd4b61efbd [CostModel] Remove VF from IntrinsicCostAttributes
getIntrinsicInstrCost takes a IntrinsicCostAttributes holding various
parameters of the intrinsic being costed. It can either be called with a
scalar intrinsic (RetTy==Scalar, VF==1), with a vector instruction
(RetTy==Vector, VF==1) or from the vectorizer with a scalar type and
vector width (RetTy==Scalar, VF>1). A RetTy==Vector, VF>1 is considered
an error. Both of the vector modes are expected to be treated the same,
but because this is confusing many backends end up getting it wrong.

Instead of trying work with those two values separately this removes the
VF parameter, widening the RetTy/ArgTys by VF used called from the
vectorizer. This keeps things simpler, but does require some other
modifications to keep things consistent.

Most backends look like this will be an improvement (or were not using
getIntrinsicInstrCost). AMDGPU needed the most changes to keep the code
from c230965ccf working. ARM removed the fix in
dfac521da1, webassembly happens to get a fixup for an SLP cost
issue and both X86 and AArch64 seem to now be using better costs from
the vectorizer.

Differential Revision: https://reviews.llvm.org/D95291
2021-02-23 13:03:26 +00:00
Alexey Bataev 9a4dd4de9d [SLP]No need to mark scatter load pointer as scalar as it gets vectorized.
Pointer operand of scatter loads does not remain scalar in the tree (it
gest vectorized) and thus must not be marked as the scalar that remains
scalar in vectorized form.

Differential Revision: https://reviews.llvm.org/D96818
2021-02-22 11:58:28 -08:00
Jinsong Ji 9202806241 Revert "[CostModel] Remove VF from IntrinsicCostAttributes"
This reverts commit 502a67dd7f.

This expose a failure in test-suite build on PowerPC,
revert to unblock buildbot first,
Dave will re-commit in https://reviews.llvm.org/D96287.

Thanks Dave.
2021-02-09 02:14:14 +00:00
David Green 502a67dd7f [CostModel] Remove VF from IntrinsicCostAttributes
getIntrinsicInstrCost takes a IntrinsicCostAttributes holding various
parameters of the intrinsic being costed. It can either be called with a
scalar intrinsic (RetTy==Scalar, VF==1), with a vector instruction
(RetTy==Vector, VF==1) or from the vectorizer with a scalar type and
vector width (RetTy==Scalar, VF>1). A RetTy==Vector, VF>1 is considered
an error. Both of the vector modes are expected to be treated the same,
but because this is confusing many backends end up getting it wrong.

Instead of trying work with those two values separately this removes the
VF parameter, widening the RetTy/ArgTys by VF used called from the
vectorizer. This keeps things simpler, but does require some other
modifications to keep things consistent.

Most backends look like this will be an improvement (or were not using
getIntrinsicInstrCost). AMDGPU needed the most changes to keep the code
from c230965ccf working. ARM removed the fix in
dfac521da1, webassembly happens to get a fixup for an SLP cost
issue and both X86 and AArch64 seem to now be using better costs from
the vectorizer.

Differential Revision: https://reviews.llvm.org/D95291
2021-02-05 09:34:24 +00:00
Sander de Smalen 171d12489f [SLPVectorizer] NFC: Migrate getVectorCallCosts to use InstructionCost.
This change also changes getReductionCost to return InstructionCost,
and it simplifies two expressions by removing a redundant 'isValid' check.
2021-01-25 12:27:01 +00:00
Sanjay Patel 77adbe6a8c [SLP] fix fast-math requirements for fmin/fmax reductions
a6f0221276 enabled intersection of FMF on reduction instructions,
so it is safe to ease the check here.

There is still some room to improve here - it looks like we
have nearly duplicate flags propagation logic inside of the
LoopUtils helper but it is limited targets that do not form
reduction intrinsics (they form the shuffle expansion).
2021-01-24 08:55:56 -05:00
Kazu Hirata 1238378f18 [llvm] Use pop_back_val (NFC) 2021-01-23 10:56:33 -08:00
Sanjay Patel a6f0221276 [SLP] fix fast-math-flag propagation on FP reductions
As shown in the test diffs, we could miscompile by
propagating flags that did not exist in the original
code.

The flags required for fmin/fmax reductions will be
fixed in a follow-up patch.
2021-01-23 11:17:20 -05:00
Anton Rapetov a4914dc1f2 [SLP] do not traverse constant uses
Walking the use list of a Constant (particularly, ConstantData)
is not scalable, since a given constant may be used by many
instructinos in many functions in many modules.

Differential Revision: https://reviews.llvm.org/D94713
2021-01-22 08:14:09 -05:00
Sanjay Patel 2f03528f5e [SLP] rename reduction variable to avoid shadowing; NFC
The code structure can likely be improved now that
'OperationData' is gone.
2021-01-21 16:02:38 -05:00
Sanjay Patel d77753381f [SLP] simplify reduction matching
This is NFC-intended and removes the "OperationData"
class which had become nothing more than a recurrence
(reduction) type.

I adjusted the matching logic to distinguish
instructions from non-instructions - that's all that
the "IsLeafValue" member was keeping track of.
2021-01-21 14:58:57 -05:00
Sanjay Patel c09be0d2a0 [SLP] reduce reduction code for checking vectorizable ops; NFC
This is another step towards removing `OperationData` and
fixing FMF matching/propagation bugs when forming reductions.
2021-01-20 11:14:48 -05:00
Sanjay Patel 1c54112a57 [SLP] refactor more reduction functions; NFC
We were able to remove almost all of the state from
OperationData, so these don't make sense as members
of that class - just pass the RecurKind in as a param.

More streamlining is possible, but I'm trying to avoid
logic/typo bugs while fixing this. Eventually, we should
not need the `OperationData` class.
2021-01-20 11:14:48 -05:00
Sanjay Patel 8590d24543 [SLP] move reduction createOp functions; NFC
We were able to remove almost all of the state from
OperationData, so these don't make sense as members
of that class - just pass the RecurKind in as a param.
2021-01-20 11:14:48 -05:00