Commit Graph

2081 Commits

Author SHA1 Message Date
Nicolai Hähnle 3fa989d4fd DomTree: remove explicit use of DomTreeNodeBase::iterator
Summary:
Almost all uses of these iterators, including implicit ones, really
only need the const variant (as it should be). The only exception is
in NewGVN, which changes the order of dominator tree child nodes.

Change-Id: I4b5bd71e32d71b0c67b03d4927d93fe9413726d4

Reviewers: arsenm, RKSimon, mehdi_amini, courbet, rriddle, aartbik

Subscribers: wdng, Prazek, hiraditya, kuhar, rogfer01, rriddle, jpienaar, shauheen, antiagainst, nicolasvasilache, arpith-jacob, mgester, lucyrfox, aartbik, liufengdb, stephenneuendorffer, Joonsoo, grosul1, vkmr, Kayjukh, jurahul, msifontes, cfe-commits, llvm-commits

Tags: #clang, #mlir, #llvm

Differential Revision: https://reviews.llvm.org/D83087
2020-07-08 18:18:49 +02:00
Stanislav Mekhanoshin 64030099c3 SLP: honor requested max vector size merging PHIs
At the moment this place does not check maximum size set
by TTI and just creates a maximum possible vectors.

Differential Revision: https://reviews.llvm.org/D82227
2020-07-08 08:06:15 -07:00
Florian Hahn 04b85e2bcb Revert "[SLP] Make sure instructions are ordered when computing spill cost."
This seems to break http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/24371

This reverts commit eb46137daa.
2020-07-07 23:15:01 +01:00
Ayal Zaks 7bf299c8d8 [LV] Vectorize without versioning-for-unit-stride under -Os/-Oz
If a loop is in a function marked OptSize, Loop Access Analysis should refrain
from generating runtime checks for unit strides that will version the loop.

If a loop is in a function marked OptSize and its vectorization is enabled, it
should be vectorized w/o any versioning.

Fixes PR46228.

Differential Revision: https://reviews.llvm.org/D81345
2020-07-07 15:04:21 +03:00
Jordan Rupprecht 10c82eecbc Revert "[LV] Enable the LoopVectorizer to create pointer inductions"
This reverts commit a8fe12065e.

It causes a crash when building gzip. Will post the detailed reduced test case to D81267.
2020-07-06 17:50:38 -07:00
Florian Hahn cff5739157 [LV] Pass dbgs() to verifyFunction call.
This is done in other places of the pass already and improves the output
on verification failure.
2020-07-06 15:09:20 +01:00
Florian Hahn eb46137daa [SLP] Make sure instructions are ordered when computing spill cost.
The entries in VectorizableTree are not necessarily ordered by their
position in basic blocks. Collect them and order them by dominance so
later instructions are guaranteed to be visited first. For instructions
in different basic blocks, we only scan to the beginning of the block,
so their order does not matter, as long as all instructions in a basic
block are grouped together. Using dominance ensures a deterministic order.

The modified test case contains an example where we compute a wrong
spill cost (2) without this patch, even though there is no call between
any instruction in the bundle.

This seems to have limited practical impact, .e.g on X86 with a recent
Intel Xeon CPU with -O3 -march=native -flto on MultiSource,SPEC2000,SPEC2006
there are no binary changes.

Reviewers: craig.topper, RKSimon, xbolva00, ABataev, spatel

Reviewed By: ABataev

Differential Revision: https://reviews.llvm.org/D82444
2020-07-03 17:30:17 +01:00
Anna Welker a8fe12065e [LV] Enable the LoopVectorizer to create pointer inductions
This patch enables the LoopVectorizer to build a phi of pointer
type and provide the vector loads and stores with vector type
getelementptrs built from the pointer induction variable, which
produces much less instructions than the previous approach of
creating scalar getelementpointers and glue them together to a
vector.

Differential Revision: https://reviews.llvm.org/D81267
2020-07-02 11:39:28 +01:00
Sanjay Patel b6315aee5b [VectorCombine] try to form vector compare and binop to eliminate scalar ops
binop i1 (cmp Pred (ext X, Index0), C0), (cmp Pred (ext X, Index1), C1)
-->
vcmp = cmp Pred X, VecC
ext (binop vNi1 vcmp, (shuffle vcmp, Index1)), Index0

This is a larger pattern than the existing extractelement folds because we can't
reasonably vectorize the sub-patterns with constants based on cost model calcs
(it doesn't usually make sense to replace a single extracted scalar op with
constant operand with a vector op).

I salvaged as much of the existing logic as I could, but there might be better
ways to share and reduce code.

The motivating case from PR43745:
https://bugs.llvm.org/show_bug.cgi?id=43745
...is the special case of a 2-way reduction. We tried to get SLP to handle that
particular pattern in D59710, but that caused crashing and regressions.
This patch is more general, but hopefully safer.

The v2f64 test with SSE2 surprised me - the cost model accounting looks like this:
OldCost = 0 (free extract of f64 at index 0) + 1 (extract of f64 at index 1) + 2 (scalar fcmps) + 1 (and of bools) = 4
NewCost = 2 (vector fcmp) + 1 (shuffle) + 1 (vector 'and') + 1 (extract of bool) = 5

Differential Revision: https://reviews.llvm.org/D82474
2020-06-29 10:38:52 -04:00
Sanjay Patel 3b95d8346d [VectorCombine] refactor - make helper function for extract to shuffle logic; NFC
Preliminary for D82474
2020-06-29 09:55:34 -04:00
Florian Hahn c0cdba727a [VPlan] Add & use VPValue for VPWidenGEPRecipe operands (NFC).
This patch adds VPValue version of the GEP's operands to
VPWidenGEPRecipe and uses them during code-generation.

Reviewers: Ayal, gilr, rengolin

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D80220
2020-06-26 20:59:17 +01:00
Guillaume Chatelet 1507fc1506 [Alignment][NFC] Migrate TTI::isLegalToVectorize{Load,Store}Chain to Align
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82653
2020-06-26 14:14:27 +00:00
Guillaume Chatelet b66e33a689 [Alignment][NFC] Migrate TTI::getGatherScatterOpCost to Align
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82577
2020-06-26 11:08:27 +00:00
Guillaume Chatelet fdc7c7fb87 [Alignment][NFC] Migrate TTI::getInterleavedMemoryOpCost to Align
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82573
2020-06-26 11:00:53 +00:00
Guillaume Chatelet 7e1f79c3de [Alignment][NFC] Migrate TTI::getMaskedMemoryOpCost to Align
This is patch is part of a series to introduce an Alignment type.
See this thread for context: http://lists.llvm.org/pipermail/llvm-dev/2019-July/133851.html
See this patch for the introduction of the type: https://reviews.llvm.org/D64790

Differential Revision: https://reviews.llvm.org/D82569
2020-06-26 10:14:16 +00:00
Simon Pilgrim 1b10c618e9 LoopVectorize.h - reduce AliasAnalysis.h include to forward declaration. NFC.
Replace legacy AliasAnalysis typedef with AAResults where necessary.
2020-06-26 10:49:00 +01:00
dfukalov 7ddee0922f [NFCI][CostModel] Add const to Value*.
Summary:
Get back `const` partially lost in one of recent changes.
Additionally specify explicit qualifiers in few places.

Reviewers: samparker

Reviewed By: samparker

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D82383
2020-06-24 23:16:08 +03:00
Florian Hahn 35bb9bfbb0 [SLP] Limit GEP lists based on width of index computation.
D68667 introduced a tighter limit to the number of GEPs to simplify
together. The limit was based on the vector element size of the pointer,
but the pointers themselves are not actually put in vectors.

IIUC we try to vectorize the index computations here, so we should base
the limit on the vector element size of the computation of the index.

This restores the test regression on AArch64 and also restores the
vectorization for a important pattern in SPEC2006/464.h264ref on
AArch64 (@test_i16_extend). We get a large benefit from doing a single
load up front and then processing the index computations in vectors.

Note that we could probably even further improve the AArch64 codegen, if
we would do zexts to i32 instead of i64 for the sub operands and then do
a single vector sext on the result of the subtractions. AArch64 provides
dedicated vector instructions to do so. Sketch of proof in Alive:
https://alive2.llvm.org/ce/z/A4xYAB

Reviewers: craig.topper, RKSimon, xbolva00, ABataev, spatel

Reviewed By: ABataev, spatel

Differential Revision: https://reviews.llvm.org/D82418
2020-06-24 19:56:53 +01:00
Sanjay Patel a0f967418f [VectorCombine] give invalid index value a name; NFC 2020-06-24 11:10:36 -04:00
Sanjay Patel 54143e2bd5 [VectorCombine] do not use magic number for undef mask element; NFC 2020-06-22 20:47:09 -04:00
Sanjay Patel 9934cc544c [VectorCombine] make helper function for shift-shuffle; NFC
This will probably be useful for other extract patterns.
2020-06-22 12:23:52 -04:00
Sanjay Patel 98c2f4eea5 [VectorCombine] add helper to replace uses and rename
The tests are regenerated to show a path that missed renaming,
but there should be no functional difference from this patch.
2020-06-22 09:58:49 -04:00
Sanjay Patel de65b356dc [VectorCombine] add/use pass-level IRBuilder
This saves creating/destroying a builder every time we
perform some transform.

The tests show instruction ordering diffs resulting from
always inserting at the root instruction now, but those
should be benign.
2020-06-22 09:01:29 -04:00
Sanjay Patel cce625f73d [VectorCombine] improve IR debugging by providing/salvaging value names
The tests are regenerated to show the diffs, but there should be no
functional change from this patch.
2020-06-22 08:35:47 -04:00
Sanjay Patel 6bdd531af5 [VectorCombine] create class for pass to hold analyses, etc; NFC
This doesn't change anything currently, but it would make sense
to create a class-level IRBuilder instead of recreating that
everywhere. As we expand to more optimizations, we will probably
also want to hold things like the DataLayout or other constant
refs in here too.
2020-06-21 16:07:33 -04:00
Sanjay Patel 741e20f3d6 [VectorCombine] fix assert for type of compare operand
As shown in the post-commit comment for D81661 - we need to
loosen the type assertion to allow scalarization of a compare
for vectors of pointers.
2020-06-20 15:20:17 -04:00
Sanjay Patel 216a37bb46 [VectorCombine] refactor extract-extract logic; NFCI 2020-06-19 14:52:27 -04:00
Sanjay Patel 6d864097a2 [VectorCombine] fix crash while transforming constants
This is a variation of the proposal in D82049 with an extra test.
2020-06-19 12:30:32 -04:00
Sanjay Patel 46a285ad9e [IRBuilder] add/use wrapper to create a generic compare based on predicate type; NFC
The predicate can always be used to distinguish between icmp and fcmp,
so we don't need to keep repeating this check in the callers.
2020-06-18 15:47:06 -04:00
Simon Pilgrim a5f1f9c9b8 ScalarEvolution.h - reduce LoopInfo.h include to forward declarations. NFC.
Move ScalarEvolution::forgetLoopDispositions implementation to ScalarEvolution.cpp to remove the dependency.

Add implicit header dependency to source files where necessary.
2020-06-17 15:48:23 +01:00
Sjoerd Meijer c1034d044a Follow up of rGe345d547a0d5, and attempt to pacify buildbot:
"error: 'get' is deprecated: The base class version of get with the scalable
argument defaulted to false is deprecated."

Changed VectorType::get() -> FixedVectorType::get().
2020-06-17 13:24:09 +01:00
Sjoerd Meijer e345d547a0 Recommit "[LV] Emit @llvm.get.active.lane.mask for tail-folded loops"
Fixed ARM regression test.

Please see the original commit message rG47650451738c for details.
2020-06-17 13:12:15 +01:00
Sjoerd Meijer d4e183f686 Revert "[LV] Emit @llvm.get.active.mask for tail-folded loops"
This reverts commit 4765045173
while I investigate the build bot failures.
2020-06-17 10:09:54 +01:00
Sjoerd Meijer 4765045173 [LV] Emit @llvm.get.active.mask for tail-folded loops
This emits new IR intrinsic @llvm.get.active.mask for tail-folded vectorised
loops if the intrinsic is supported by the backend, which is checked by
querying TargetTransform hook emitGetActiveLaneMask.

This intrinsic creates a mask representing active and inactive vector lanes,
which is used by the masked load/store instructions that are created for
tail-folded loops. The semantics of @llvm.get.active.mask are described here in
LangRef:

https://llvm.org/docs/LangRef.html#llvm-get-active-lane-mask-intrinsics

This intrinsic is also used to provide a hint to the backend. That is, the
second argument of the intrinsic represents the back-edge taken count of the
loop. For MVE, for example, we use that to set up tail-predication, which is a
new form of predication in MVE for vector loops that implicitely predicates the
last vector loop iteration by implicitely setting active/inactive lanes, i.e.
the tail loop is predicated. In order to set up a tail-predicated vector loop,
we need to know the number of data elements processed by the vector loop, which
corresponds the the tripcount of the scalar loop, which we can now reconstruct
using @llvm.get.active.mask.

Differential Revision: https://reviews.llvm.org/D79100
2020-06-17 09:53:58 +01:00
Christopher Tetreault ff628f5f5e [SVE] Eliminate calls to default-false VectorType::get() from Vectorize
Reviewers: efriedma, fhahn, spatel, sdesmalen, kmclaughlin

Reviewed By: efriedma

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D81521
2020-06-16 12:50:13 -07:00
Sanjay Patel ed67f5e7ab [VectorCombine] scalarize compares with insertelement operand(s)
Generalize scalarization (recently enhanced with D80885)
to allow compares as well as binops.
Similar to binops, we are avoiding scalarization of a loaded
value because that could avoid a register transfer in codegen.
This requires 1 extra predicate that I am aware of: we do not
want to scalarize the condition value of a vector select. That
might also invert a transform that we do in instcombine that
prefers a vector condition operand for a vector select.

I think this is the final step in solving PR37463:
https://bugs.llvm.org/show_bug.cgi?id=37463

Differential Revision: https://reviews.llvm.org/D81661
2020-06-16 13:48:10 -04:00
Sam Parker 2596da3174 [CostModel] getCFInstrCost in getUserCost.
Have BasicTTI call the base implementation so that both agree on the
default behaviour, which the default being a cost of '1'. This has
required an X86 specific implementation as it seems to be very
reliant on those instructions being free. Changes are also made to
AMDGPU so that their implementations distinguish between cost kinds,
so that the unrolling isn't affected. PowerPC also has its own
implementation to prevent changes to the reg-usage vectorizer test.

The cost model test changes now reflect that ret instructions are not
generally free.

Differential Revision: https://reviews.llvm.org/D79164
2020-06-15 09:28:46 +01:00
Roman Lebedev 7aeb41b3c8
[NFCI] VectorCombine: add statistic for bitcast(shuf()) -> shuf(bitcast()) xform 2020-06-12 23:10:53 +03:00
Florian Hahn 3a846d4d92 [VPlan] Reject loops without computable backedge taken counts
getOrCreateTripCount is used to generate code for the outer loop, but it
requires a computable backedge taken counts. Check that in the VPlan
native path.

Reviewers: Ayal, gilr, rengolin, sguggill

Reviewed By: sguggill

Differential Revision: https://reviews.llvm.org/D81088
2020-06-12 10:31:18 +01:00
Sanjay Patel 039ff29ef6 [VectorCombine] remove unused parameters; NFC 2020-06-11 19:15:03 -04:00
Simon Pilgrim 5dc4e7c2b9 [VectorCombine] scalarizeBinop - support an all-constant src vector operand
scalarizeBinop currently folds

  vec_bo((inselt VecC0, V0, Index), (inselt VecC1, V1, Index))
  ->
  inselt(vec_bo(VecC0, VecC1), scl_bo(V0,V1), Index)

This patch extends this to account for cases where one of the vec_bo operands is already all-constant and performs similar cost checks to determine if the scalar binop with a constant still makes sense:

  vec_bo((inselt VecC0, V0, Index), VecC1)
  ->
  inselt(vec_bo(VecC0, VecC1), scl_bo(V0,extractelt(V1,Index)), Index)

Fixes PR42174

Differential Revision: https://reviews.llvm.org/D80885
2020-06-09 19:02:05 +01:00
Benjamin Kramer 3badd17b69 SmallPtrSet::find -> SmallPtrSet::count
The latter is more readable and more efficient. While there clean up
some double lookups. NFCI.
2020-06-07 22:38:08 +02:00
Simon Pilgrim 5006e551d3 LoopAnalysisManager.h - reduce includes to forward declarations. NFC.
Move implicit include dependencies down to header/source files.
2020-06-06 14:06:46 +01:00
Florian Hahn 211596c94e [VPlan] Support extracting lanes for defs managed in VPTransformState.
Currently extracting a lane for a VPValue def is not supported, if it is
managed directly by VPTransformState (e.g. because it is created by a
VPInstruction or an external VPValue def).

For now, simply extract the requested lane. In the future, we should
also cache the extracted scalar values, similar to LV.

Reviewers: Ayal, rengolin, gilr, SjoerdMeijer

Reviewed By: SjoerdMeijer

Differential Revision: https://reviews.llvm.org/D80787
2020-06-03 12:14:16 +01:00
Florian Hahn b446ec56a2 [LV] Make sure the MaxVF is a power-of-2 by rounding down.
LV currently only supports power of 2 vectorization factors, which has
been made explicit with the assertion added in
840450549c.

However, if the widest type is not a power-of-2 the computed MaxVF won't
be a power-of-2 either. This patch updates computeFeasibleMaxVF to
ensure the returned value is a power-of-2 by rounding down to the
nearest power-of-2.

Fixes PR46139.

Reviewers: Ayal, gilr, rengolin

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D80870
2020-06-02 10:40:49 +01:00
Valery N Dmitriev a45688a72c [SLP] Apply external to vectorizable tree users cost adjustment for
relevant aggregate build instructions only (UserCost).
Users are detected with findBuildAggregate routine and the trick is
that following SLP vectorization may end up vectorizing entire list
with smaller chunks. Cost adjustment then is applied for individual
chunks and these adjustments obviously have to be smaller than the
entire aggregate build cost.

Differential Revision: https://reviews.llvm.org/D80773
2020-05-29 15:37:41 -07:00
Christopher Tetreault d2befc6633 [SVE] Eliminate calls to default-false VectorType::get() from Vectorize
Reviewers: efriedma, c-rhodes, david-arm, fhahn

Reviewed By: david-arm

Subscribers: tschuett, hiraditya, rkruppe, psnobl, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D80339
2020-05-29 11:31:24 -07:00
Florian Hahn 9b507b2127 [LAA] We only need pointer checks if there are non-zero checks (NFC).
If it turns out that we can do runtime checks, but there are no
runtime-checks to generate, set RtCheck.Need to false.

This can happen if we can prove statically that the pointers passed in
to canCheckPtrAtRT do not alias. This should not change any results, but
allows us to skip some work and assert that runtime checks are
generated, if LAA indicates that runtime checks are required.

Reviewers: anemet, Ayal

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D79969

Note: This is a recommit of 259abfc7cb,
with some suggested renaming.
2020-05-27 12:47:36 +01:00
Florian Hahn 2d0389821e Revert "[LAA] We only need pointer checks if there are non-zero checks (NFC)."
This reverts commit 259abfc7cb.

Reverting this, as I missed a case where we return without setting
RtCheck.Need.
2020-05-27 12:39:45 +01:00
Florian Hahn 259abfc7cb [LAA] We only need pointer checks if there are non-zero checks (NFC).
If it turns out that we can do runtime checks, but there are no
runtime-checks to generate, set RtCheck.Need to false.

This can happen if we can prove statically that the pointers passed in
to canCheckPtrAtRT do not alias. This should not change any results, but
allows us to skip some work and assert that runtime checks are
generated, if LAA indicates that runtime checks are required.

Reviewers: anemet, Ayal

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D79969
2020-05-27 12:37:20 +01:00
Simon Pilgrim 35963f6d85 VPlanValue.h - reduce unnecessary includes to forward declarations. NFC. 2020-05-27 11:26:14 +01:00
Ayal Zaks 840450549c [LV] Clamp MaxVF to power of 2.
If a loop has a constant trip count known to be a multiple of MaxVF (times user
UF), LV infers that no tail will be generated for any chosen VF. This relies on
the chosen VF's being powers of 2 bound by MaxVF, and assumes MaxVF is a power
of 2. Make sure the latter holds, in particular when MaxVF is set by a memory
dependence distance which may not be a power of 2.

Differential Revision: https://reviews.llvm.org/D80491
2020-05-25 11:24:33 +03:00
Florian Hahn 0deab8a54f [LV] Either get invariant condition OR vector condition.
Currently we unconditionally get the first lane of the condition
operand, even if we later use the full vector condition. This can result
in some unnecessary instructions being generated.

Suggested as follow-up in D80219.
2020-05-24 17:16:42 +01:00
Sanjay Patel 7eed772a27 [PatternMatch] abbreviate vector inst matchers; NFC
Readability is not reduced with these opcodes/match lines,
so reduce odds of awkward wrapping from 80-col limit.
2020-05-24 09:19:47 -04:00
Florian Hahn 15224408f0 [VPlan] Use VPUser for VPWidenSelectRecipe operands (NFC).
VPWidenSelectRecipe already contains a VPUser, but it is not used. This
patch updates the code related to VPWidenSelectRecipe to use VPUser for
its operands.

Reviewers: Ayal, gilr, rengolin

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D80219
2020-05-24 13:58:08 +01:00
Sanjay Patel 024098ae53 [VectorCombine] set preserve alias analysis
As noted in D80236, moving the pass in the pipeline exposed this
shortcoming. Extra work to recalculate the alias results showed
up as a compile-time slowdown.
2020-05-22 16:25:16 -04:00
Anh Tuyen Tran 13bf6039c9 Title: [LV] Handle Fold-Tail of loops with vectorizarion factor equal to 1
Summary:
When handling loops whose VF is 1, fold-tail vectorization sets the
backedge taken count of the original loop with a vector of a single
element. This causes type-mismatch during instruction generartion.

The purpose of this patch is toto address the case of VF==1.

Reviewer: Ayal (Ayal Zaks), bmahjour (Bardia Mahjour), fhahn (Florian Hahn), gilr (Gil Rapaport), rengolin (Renato Golin)

Reviewed By: Ayal (Ayal Zaks), bmahjour (Bardia Mahjour), fhahn (Florian Hahn)

Subscribers: Ayal (Ayal Zaks), rkruppe (Hanna Kruppe), bmahjour (Bardia Mahjour), rogfer01 (Roger Ferrer Ibanez), vkmr (Vineet Kumar), bollu (Siddharth Bhat), hiraditya (Aditya Kumar), llvm-commits (Mailing List llvm-commits)

Tag: LLVM

Differential Revision: https://reviews.llvm.org/D79976
2020-05-22 13:30:56 +00:00
Sanjay Patel 21f7cf4057 [SLP] fix verification check for valid IR
This is a fix for PR45965 - https://bugs.llvm.org/show_bug.cgi?id=45965 -
which was left out of D80106 because of a test failure.

SLP does its own mini-CSE after potentially creating redundant instructions,
so we need to wait for that to complete before running the verifier.
Otherwise, we will see a test failure for
test/Transforms/SLPVectorizer/X86/crash_vectorizeTree.ll (not changed here)
because a phi temporarily has identical but different incoming values for
the same incoming block.

A related, but independent, test that would have been altered here was
fixed with:
rG880df55

The test was escaping verification in SLP without this change because we
were not running verifyFunction() unless SLP actually changed the IR.

Differential Revision: https://reviews.llvm.org/D80401
2020-05-22 09:15:27 -04:00
Dinar Temirbulatov df3b95bc0a [SLP][NFC] PR45269 getVectorElementSize() is slow
The algorithm inside getVectorElementSize() is almost O(x^2) complexity and
when, for example, we compile MultiSource/Applications/ClamAV/shared_sha256.c
with 1k instructions inside sha256_transform() function that resulted in almost
~800k iterations. The following change improves the algorithm with the map to
a liner complexity.

Differential Revision: https://reviews.llvm.org/D80241
2020-05-21 17:26:50 +02:00
Sam Parker 8cc911fa5b [NFCI][CostModel] Refactor getIntrinsicInstrCost
Combine the two API calls into one by introducing a structure to hold
the relevant data. This has the added benefit of moving the boiler
plate code for arguments and flags, into the constructors. This is
intended to be a non-functional change, but the complicated web of
logic involved here makes it very hard to guarantee.

Differential Revision: https://reviews.llvm.org/D79941
2020-05-20 11:59:08 +01:00
Florian Hahn bcbd26bfe6 [SCEV] Move ScalarEvolutionExpander.cpp to Transforms/Utils (NFC).
SCEVExpander modifies the underlying function so it is more suitable in
Transforms/Utils, rather than Analysis. This allows using other
transform utils in SCEVExpander.

This patch was originally committed as b8a3c34eee, but broke the
modules build, as LoopAccessAnalysis was using the Expander.

The code-gen part of LAA was moved to lib/Transforms recently, so this
patch can be landed again.

Reviewers: sanjoy.google, efriedma, reames

Reviewed By: sanjoy.google

Differential Revision: https://reviews.llvm.org/D71537
2020-05-20 10:53:40 +01:00
Florian Hahn 7cefd1b4cd [LV] Remove duplicated return stmt (NFC). 2020-05-19 17:20:50 +01:00
Florian Hahn cff9399f6b [VPlan] Fix comment for User in VPWidenSelectRecipe (NFC).
The comment was referring the arguments of the call, but the recipe
widens a select.
2020-05-19 15:31:39 +01:00
Florian Hahn f828d75b46 [VPlan] Add & use VPValue operands for VPReplicateRecipe (NFC).
This patch adds VPValue version of the instruction operands to
VPReplicateRecipe and uses them during code-generation.

Reviewers: Ayal, gilr, rengolin

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D80114
2020-05-19 15:12:17 +01:00
Florian Hahn 66ad107452 [VPlan] Remove unique_ptr from VPBranchOnRecipeMask (NFC).
We can remove a dynamic memory allocation, by checking the number of
operands: no operands = all true, 1 operand = mask.

Reviewers: Ayal, gilr, rengolin

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D80110
2020-05-19 15:01:37 +01:00
Eli Friedman 27b4e6931d [NFC] Replace MaybeAlign with Align in TargetTransformInfo. 2020-05-18 19:25:49 -07:00
Ayal Zaks 682e739638 [LV] Fix FoldTail under user VF and UF
LV considers an internally computed MaxVF to decide if a constant trip-count is
a multiple of any subsequently chosen VF, and conclude that no scalar remainder
iterations (tail) will be left for Fold Tail to handle. If an external VF is
provided via -force-vector-width, it must be considered instead of the internal
MaxVF.
If an external UF is provided via -force-vector-interleave, it too must be
considered in addition to MaxVF or user VF.

Fixes PR45679.

Differential Revision: https://reviews.llvm.org/D80085
2020-05-19 01:32:25 +03:00
Craig Topper c9f63297e2 Fix several places that were calling verifyFunction or verifyModule without checking the return value.
verifyFunction/verifyModule don't assert or error internally. They
also don't print anything if you don't pass a raw_ostream to them.
So the caller needs to check the result and ideally pass a stream
to get the messages. Otherwise they're just really expensive no-ops.

I've filed PR45965 for another instance in SLPVectorizer
that causes a lit test failure.

Differential Revision: https://reviews.llvm.org/D80106
2020-05-18 13:28:46 -07:00
Volkan Keles 63081dc6f6 LoadStoreVectorizer: Match nested adds to prove vectorization is safe
If both OpA and OpB is an add with NSW/NUW and with the same LHS operand,
we can guarantee that the transformation is safe if we can prove that OpA
won't overflow when IdxDiff added to the RHS of OpA.

Review: https://reviews.llvm.org/D79817
2020-05-18 12:13:01 -07:00
Nikita Popov 52e98f620c [Alignment] Remove unnecessary getValueOrABITypeAlignment calls (NFC)
Now that load/store alignment is required, we no longer need most
of them. Also switch the getLoadStoreAlignment() helper to return
Align instead of MaybeAlign.
2020-05-17 22:19:15 +02:00
Sanjay Patel 81e9ede3a2 [VectorCombine] forward walk through instructions to improve chaining of transforms
This is split off from D79799 - where I was proposing to fully iterate
over a function until there are no more transforms. I suspect we are
still going to want to do something like that eventually.

But we can achieve the same gains much more efficiently on the current
set of regression tests just by reversing the order that we visit the
instructions.

This may also reduce the motivation for D79078, but we are still not
getting the optimal pattern for a reduction.
2020-05-16 13:08:01 -04:00
Florian Hahn 4c8285c750 [VPlan] Move emission of \\l\"+\n to dumpBasicBlock (NFC).
The patch standardizes printing of VPRecipes a bit, by hoisting out the
common emission of \\l\"+\n. It simplifies the code and is also a first
step towards untangling printing from DOT format output, with the goal
of making the DOT output optional and to provide a more concise debug
output if DOT output is disabled.

Reviewers: gilr, Ayal, rengolin

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D78883
2020-05-14 13:07:59 +01:00
Alina Sbirlea bd541b217f [NewPassManager] Add assertions when getting statefull cached analysis.
Summary:
Analyses that are statefull should not be retrieved through a proxy from
an outer IR unit, as these analyses are only invalidated at the end of
the inner IR unit manager.
This patch disallows getting the outer manager and provides an API to
get a cached analysis through the proxy. If the analysis is not
stateless, the call to getCachedResult will assert.

Reviewers: chandlerc

Subscribers: mehdi_amini, eraman, hiraditya, zzheng, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72893
2020-05-13 12:38:38 -07:00
Sjoerd Meijer 9529597cf4 Recommit #2: "[LV] Induction Variable does not remain scalar under tail-folding."
This was reverted because of a miscompilation. At closer inspection, the
problem was actually visible in a changed llvm regression test too. This
one-line follow up fix/recommit will splat the IV, which is what we are trying
to avoid if unnecessary in general, if tail-folding is requested even if all
users are scalar instructions after vectorisation. Because with tail-folding,
the splat IV will be used by the predicate of the masked loads/stores
instructions. The previous version omitted this, which caused the
miscompilation. The original commit message was:

If tail-folding of the scalar remainder loop is applied, the primary induction
variable is splat to a vector and used by the masked load/store vector
instructions, thus the IV does not remain scalar. Because we now mark
that the IV does not remain scalar for these cases, we don't emit the vector IV
if it is not used. Thus, the vectoriser produces less dead code.

Thanks to Ayal Zaks for the direction how to fix this.
2020-05-13 13:50:09 +01:00
Sanjay Patel 5f730b645d [VectorCombine] account for extra uses in scalarization cost
Follow-up to D79452.
Mimics the extra use cost formula for the inverse transform with extracts.
2020-05-11 15:20:57 -04:00
Florian Hahn 8528186b9b [LAA] Move runtime-check generation to Transforms/Utils/loopUtils (NFC)
Currently LAA's uses of ScalarEvolutionExpander blocks moving the
expander from Analysis to Transforms. Conceptually the expander does not
fit into Analysis (it is only used for code generation) and
runtime-check generation also seems to be better suited as a
transformation utility.

Reviewers: Ayal, anemet

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D78460
2020-05-10 17:39:26 +01:00
Florian Hahn 96c63f544f Recommit "[LAA] Remove one addRuntimeChecks function (NFC)."
The failing assertion has been fixed and the problematic test case has
been added.

This reverts the revert commit fc44617f28.
2020-05-10 15:19:57 +01:00
Florian Hahn fc44617f28 Revert "[LAA] Remove one addRuntimeChecks function (NFC)."
This reverts commit c28114c8ff.

This causes some bots to fail:

http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-android/builds/30596/steps/build%20android%2Faarch64/logs/stdio
2020-05-10 13:28:00 +01:00
Florian Hahn c28114c8ff [LAA] Remove one addRuntimeChecks function (NFC).
In order to reduce the API surface area (preparation for D78460), remove
a addRuntimeChecks() function and do the additional check in the single
caller.

Reviewers: Ayal, anemet

Reviewed By: Ayal

Differential Revision: https://reviews.llvm.org/D79679
2020-05-10 12:48:55 +01:00
Sanjay Patel 0d2a0b44c8 [VectorCombine] scalarize binop of inserted elements into vector constants
As with the extractelement patterns that are currently in vector-combine,
there are going to be several possible variations on this theme. This
should be the clearest, simplest example.

Scalarization is the right direction for target-independent canonicalization,
and InstCombine has some of those folds already, but it doesn't do this.
I proposed a similar transform in D50992. Here in vector-combine, we can
check the cost model to be sure it's profitable, so there should be less risk.

Differential Revision: https://reviews.llvm.org/D79452
2020-05-08 16:31:12 -04:00
Benjamin Kramer f936457f80 Revert "Recommit "[LV] Induction Variable does not remain scalar under tail-folding.""
This reverts commit ae45b4dbe7. It
causes miscompilations, test case on the mailing list.
2020-05-08 14:49:10 +02:00
Sanjay Patel 02051c7f3a [SLP] add another bailout for load-combine patterns (2nd try)
The original patch (rG86dfbc676ebe) exposed an existing bug:
we could wrongly cast a constant expression to BinaryOperator
because the pattern matching allows that. This adds a check
for that case, and there's a reduced test case to verify no
crashing.

Original commit message:

This builds on the or-reduction bailout that was added with D67841.
We still do not have IR-level load combining, although that could
be a target-specific enhancement for -vector-combiner.

The heuristic is narrowly defined to catch the motivating case from
PR39538:
https://bugs.llvm.org/show_bug.cgi?id=39538
...while preserving existing functionality.

That is, there's an unmodified test of pure load/zext/store that is
not seen in this patch at llvm/test/Transforms/SLPVectorizer/X86/cast.ll.
That's the reason for the logic difference to require the 'or'
instructions. The chances that vectorization would actually help a
memory-bound sequence like that seem small, but it looks nicer with:

  vpmovzxwd     (%rsi), %xmm0
  vmovdqu       %xmm0, (%rdi)

rather than:

  movzwl        (%rsi), %eax
  movl  %eax, (%rdi)
  ...

In the motivating test, we avoid creating a vector mess that is
unrecoverable in the backend, and SDAG forms the expected bswap
instructions after load combining:

  movzbl (%rdi), %eax
  vmovd %eax, %xmm0
  movzbl 1(%rdi), %eax
  vmovd %eax, %xmm1
  movzbl 2(%rdi), %eax
  vpinsrb $4, 4(%rdi), %xmm0, %xmm0
  vpinsrb $8, 8(%rdi), %xmm0, %xmm0
  vpinsrb $12, 12(%rdi), %xmm0, %xmm0
  vmovd %eax, %xmm2
  movzbl 3(%rdi), %eax
  vpinsrb $1, 5(%rdi), %xmm1, %xmm1
  vpinsrb $2, 9(%rdi), %xmm1, %xmm1
  vpinsrb $3, 13(%rdi), %xmm1, %xmm1
  vpslld $24, %xmm0, %xmm0
  vpmovzxbd %xmm1, %xmm1 # xmm1 = xmm1[0],zero,zero,zero,xmm1[1],zero,zero,zero,xmm1[2],zero,zero,zero,xmm1[3],zero,zero,zero
  vpslld $16, %xmm1, %xmm1
  vpor %xmm0, %xmm1, %xmm0
  vpinsrb $1, 6(%rdi), %xmm2, %xmm1
  vmovd %eax, %xmm2
  vpinsrb $2, 10(%rdi), %xmm1, %xmm1
  vpinsrb $3, 14(%rdi), %xmm1, %xmm1
  vpinsrb $1, 7(%rdi), %xmm2, %xmm2
  vpinsrb $2, 11(%rdi), %xmm2, %xmm2
  vpmovzxbd %xmm1, %xmm1 # xmm1 = xmm1[0],zero,zero,zero,xmm1[1],zero,zero,zero,xmm1[2],zero,zero,zero,xmm1[3],zero,zero,zero
  vpinsrb $3, 15(%rdi), %xmm2, %xmm2
  vpslld $8, %xmm1, %xmm1
  vpmovzxbd %xmm2, %xmm2 # xmm2 = xmm2[0],zero,zero,zero,xmm2[1],zero,zero,zero,xmm2[2],zero,zero,zero,xmm2[3],zero,zero,zero
  vpor %xmm2, %xmm1, %xmm1
  vpor %xmm1, %xmm0, %xmm0
  vmovdqu %xmm0, (%rsi)

  movl  (%rdi), %eax
  movl  4(%rdi), %ecx
  movl  8(%rdi), %edx
  movbel        %eax, (%rsi)
  movbel        %ecx, 4(%rsi)
  movl  12(%rdi), %ecx
  movbel        %edx, 8(%rsi)
  movbel        %ecx, 12(%rsi)

Differential Revision: https://reviews.llvm.org/D78997
2020-05-07 15:04:37 -04:00
Hans Wennborg c54c6ee1a7 Revert "[SLP] add another bailout for load-combine patterns"
It caused asserts building Chromium, see discussion on
https://reviews.llvm.org/D78997

This reverts commit 86dfbc676e.
2020-05-07 16:31:52 +02:00
Sjoerd Meijer 3bbc71d6c9 [LV] Fix typo in variable name. NFC. 2020-05-07 13:53:44 +01:00
Sjoerd Meijer ae45b4dbe7 Recommit "[LV] Induction Variable does not remain scalar under tail-folding."
With 3 llvm regr tests fixed/updated that I had missed.
2020-05-07 11:52:20 +01:00
Sjoerd Meijer 20d67ffeae Revert "[LV] Induction Variable does not remain scalar under tail-folding."
This reverts commit 617aa64c84.

while I investigate buildbot failures.
2020-05-07 09:29:56 +01:00
Sjoerd Meijer 617aa64c84 [LV] Induction Variable does not remain scalar under tail-folding.
If tail-folding of the scalar remainder loop is applied, the primary induction
variable is splat to a vector and used by the masked load/store vector
instructions, thus the IV does not remain scalar. Because we now mark
that the IV does not remain scalar for these cases, we don't emit the vector IV
if it is not used. Thus, the vectoriser produces less dead code.

Thanks to Ayal Zaks for the direction how to fix this.

Differential Revision: https://reviews.llvm.org/D78911
2020-05-07 09:15:23 +01:00
Sanjay Patel 86dfbc676e [SLP] add another bailout for load-combine patterns
This builds on the or-reduction bailout that was added with D67841.
We still do not have IR-level load combining, although that could
be a target-specific enhancement for -vector-combiner.

The heuristic is narrowly defined to catch the motivating case from
PR39538:
https://bugs.llvm.org/show_bug.cgi?id=39538
...while preserving existing functionality.

That is, there's an unmodified test of pure load/zext/store that is
not seen in this patch at llvm/test/Transforms/SLPVectorizer/X86/cast.ll.
That's the reason for the logic difference to require the 'or'
instructions. The chances that vectorization would actually help a
memory-bound sequence like that seem small, but it looks nicer with:

  vpmovzxwd	(%rsi), %xmm0
  vmovdqu	%xmm0, (%rdi)

rather than:

  movzwl	(%rsi), %eax
  movl	%eax, (%rdi)
  ...

In the motivating test, we avoid creating a vector mess that is
unrecoverable in the backend, and SDAG forms the expected bswap
instructions after load combining:

  movzbl (%rdi), %eax
  vmovd %eax, %xmm0
  movzbl 1(%rdi), %eax
  vmovd %eax, %xmm1
  movzbl 2(%rdi), %eax
  vpinsrb $4, 4(%rdi), %xmm0, %xmm0
  vpinsrb $8, 8(%rdi), %xmm0, %xmm0
  vpinsrb $12, 12(%rdi), %xmm0, %xmm0
  vmovd %eax, %xmm2
  movzbl 3(%rdi), %eax
  vpinsrb $1, 5(%rdi), %xmm1, %xmm1
  vpinsrb $2, 9(%rdi), %xmm1, %xmm1
  vpinsrb $3, 13(%rdi), %xmm1, %xmm1
  vpslld $24, %xmm0, %xmm0
  vpmovzxbd %xmm1, %xmm1 # xmm1 = xmm1[0],zero,zero,zero,xmm1[1],zero,zero,zero,xmm1[2],zero,zero,zero,xmm1[3],zero,zero,zero
  vpslld $16, %xmm1, %xmm1
  vpor %xmm0, %xmm1, %xmm0
  vpinsrb $1, 6(%rdi), %xmm2, %xmm1
  vmovd %eax, %xmm2
  vpinsrb $2, 10(%rdi), %xmm1, %xmm1
  vpinsrb $3, 14(%rdi), %xmm1, %xmm1
  vpinsrb $1, 7(%rdi), %xmm2, %xmm2
  vpinsrb $2, 11(%rdi), %xmm2, %xmm2
  vpmovzxbd %xmm1, %xmm1 # xmm1 = xmm1[0],zero,zero,zero,xmm1[1],zero,zero,zero,xmm1[2],zero,zero,zero,xmm1[3],zero,zero,zero
  vpinsrb $3, 15(%rdi), %xmm2, %xmm2
  vpslld $8, %xmm1, %xmm1
  vpmovzxbd %xmm2, %xmm2 # xmm2 = xmm2[0],zero,zero,zero,xmm2[1],zero,zero,zero,xmm2[2],zero,zero,zero,xmm2[3],zero,zero,zero
  vpor %xmm2, %xmm1, %xmm1
  vpor %xmm1, %xmm0, %xmm0
  vmovdqu %xmm0, (%rsi)

  movl	(%rdi), %eax
  movl	4(%rdi), %ecx
  movl	8(%rdi), %edx
  movbel	%eax, (%rsi)
  movbel	%ecx, 4(%rsi)
  movl	12(%rdi), %ecx
  movbel	%edx, 8(%rsi)
  movbel	%ecx, 12(%rsi)

Differential Revision: https://reviews.llvm.org/D78997
2020-05-05 12:44:38 -04:00
Simon Pilgrim 4e3c005554 [TTI] getScalarizationOverhead - use explicit VectorType operand
getScalarizationOverhead is only ever called with vectors (and we already had a load of cast<VectorType> calls immediately inside the functions).

Followup to D78357

Reviewed By: @samparker

Differential Revision: https://reviews.llvm.org/D79341
2020-05-05 16:59:23 +01:00
Sam Parker 40574fefe9 [NFC][CostModel] Add TargetCostKind to relevant APIs
Make the kind of cost explicit throughout the cost model which,
apart from making the cost clear, will allow the generic parts to
calculate better costs. It will also allow some backends to
approximate and correlate the different costs if they wish. Another
benefit is that it will also help simplify the cost model around
immediate and intrinsic costs, where we currently have multiple APIs.

RFC thread:
http://lists.llvm.org/pipermail/llvm-dev/2020-April/141263.html

Differential Revision: https://reviews.llvm.org/D79002
2020-05-05 10:35:54 +01:00
Florian Hahn bbdfcf8f69 [VPlan] Remove unused & undefined print method (NFC). 2020-05-03 18:36:20 +01:00
Anh Tuyen Tran c7878ad231 [VFDatabase] Scalar functions are vector functions with VF =1
Summary:
Return scalar function when VF==1. The new trivial mapping scalar --> scalar when VF==1 to prevent false positive for "isVectorizable" query.

Author: masoud.ataei (Masoud Ataei)

Reviewers: Whitney (Whitney Tsang), fhahn (Florian Hahn), pjeeva01 (Jeeva P.), fpetrogalli (Francesco Petrogalli), rengolin (Renato Golin)

Reviewed By: fpetrogalli (Francesco Petrogalli)

Subscribers: hiraditya (Aditya Kumar), llvm-commits, LLVM

Tag: LLVM

Differential Revision: https://reviews.llvm.org/D78054
2020-04-29 17:20:37 +00:00
Simon Pilgrim 090cae8491 [TTI] Add DemandedElts to getScalarizationOverhead
The improvements to the x86 vector insert/extract element costs in D74976 resulted in the estimated costs for vector initialization and scalarization increasing higher than should be expected. This is particularly noticeable on pre-SSE4 targets where the available of legal INSERT_VECTOR_ELT ops is more limited.

This patch does 2 things:
1 - it implements X86TTIImpl::getScalarizationOverhead to more accurately represent the typical costs of a ISD::BUILD_VECTOR pattern.
2 - it adds a DemandedElts mask to getScalarizationOverhead to permit the SLP's BoUpSLP::getGatherCost to be rewritten to use it directly instead of accumulating raw vector insertion costs.

This fixes PR45418 where a v4i8 (zext'd to v4i32) was no longer vectorizing.

A future patch should extend X86TTIImpl::getScalarizationOverhead to tweak the EXTRACT_VECTOR_ELT scalarization costs as well.

Reviewed By: @craig.topper

Differential Revision: https://reviews.llvm.org/D78216
2020-04-29 12:00:38 +01:00
Florian Hahn e89379856a Recommit "[VPlan] Add & use VPValue operands for VPWidenRecipe (NFC)."
The crash that caused the original revert has been fixed in
a3c964a278. I also added a reduced version of the crash reproducer.

This reverts the revert commit 2107af9ccf.
2020-04-29 11:40:39 +01:00
Sanjay Patel 21acc0612a [SLP] refactor load-combine logic; NFC
We may want to identify sequences that are not
reductions, but still qualify as load-combines
in the back-end, so make most of the body a
helper function.
2020-04-27 16:02:37 -04:00
Ayal Zaks a3c964a278 [LV] Fix recording of BranchTakenCount for FoldTail
When folding tail, branch taken count is computed during initial VPlan execution
and recorded to be used by the compare computing the loop's mask. This recording
should directly set the State, instead of reusing Value2VPValue mapping which
serves original Values present prior to vectorization.
The branch taken count may be a constant Value, which may be used elsewhere in
the loop; trying to employ Value2VPValue for both leads to the issue reported in
https://reviews.llvm.org/D76992#inline-721028

Differential Revision: https://reviews.llvm.org/D78847
2020-04-26 20:13:10 +03:00
Max Kazantsev 9cd4debd5a [LoopVectorize] Preserve CFG analyses if CFG wasn't modified
One of transforms the loop vectorizer makes is LCSSA formation. In some cases it
is the only transform it makes. We should not drop CFG analyzes if only LCSSA was
formed and no actual CFG changes was made.

We should think of expanding this logic to other passes as well, and maybe make
it a part of PM framework.

Reviewed By: Florian Hahn
Differential Revision: https://reviews.llvm.org/D78360
2020-04-24 17:22:24 +07:00
Mehdi Amini 2107af9ccf Revert "[VPlan] Add & use VPValue operands for VPWidenRecipe (NFC)."
This reverts commit 9245c7ac13.

This is triggering a segfault in XLA downstream, we'll follow-up with
a reproducer, it is likely influenced by TTI/TLI settings or other
options as a simple `opt -loop-vectorize` invocation on the IR
before the crash does not reproduce immediately.
2020-04-24 05:07:32 +00:00
Simon Pilgrim b108a457e1 [VPlan] Remove unused forward declarations. NFC.
Move VPlan.h include from VPlanVerifier.h down to VPlanVerifier.cpp
2020-04-23 12:34:20 +01:00
Florian Hahn 9245c7ac13 [VPlan] Add & use VPValue operands for VPWidenRecipe (NFC).
This patch adds VPValue version of the instruction operands to
VPWidenRecipe and uses them during code-generation.

Similar to D76373 this reduces ingredient def-use usage by ILV as
a step towards full VPlan-based def-use relations.

Reviewers: rengolin, Ayal, gilr

Reviewed By: gilr

Differential Revision: https://reviews.llvm.org/D76992
2020-04-23 12:16:46 +01:00