19 Commits

Author SHA1 Message Date
Alexey Bataev
a0086add2e [SLP]Improve gathering of scalar elements.
1. Better sorting of scalars to be gathered. Trying to insert
   constants/arguments/instructions-out-of-loop at first and only then
   the instructions which are inside the loop. It improves hoisting of
   invariant insertelements instructions.
2. Better detection of shuffle candidates in gathering function.
3. The cost of insertelement for constants is 0.

Part of D57059.

Differential Revision: https://reviews.llvm.org/D103458
2021-06-09 05:23:21 -07:00
Anton Afanasyev
ab2c499d3a [SLP] Add insertelement instructions to vectorizable tree
Add new type of tree node for `InsertElementInst` chain forming vector.
These instructions could be either removed, or replaced by shuffles during
vectorization and we can add this node to cost model, so naturally estimating
their cost, getting rid of `CompensateCost` tricks and reducing further work
for InstCombine. This fixes PR40522 and PR35732 in a natural way. Also this
patch is the first step towards revectorization of partially vectorization
(to fix PR42022 completely). After adding inserts to tree the next step is
to add vector instructions there (for instance, to merge `store <2 x float>`
and `store <2 x float>` to `store <4 x float>`).

Fixes PR40522 and PR35732.

Differential Revision: https://reviews.llvm.org/D98714
2021-05-13 07:41:45 +03:00
Juneyoung Lee
4a8e6ed2f7 [SLP,LV] Use poison constant vector for shufflevector/initial insertelement
This patch makes SLP and LV emit operations with initial vectors set to poison constant instead of undef.
This is a part of efforts for using poison vector instead of undef to represent "doesn't care" vector.
The goal is to make nice shufflevector optimizations valid that is currently incorrect due to the tricky interaction between undef and poison (see https://bugs.llvm.org/show_bug.cgi?id=44185 ).

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D94061
2021-01-06 11:22:50 +09:00
Juneyoung Lee
278aa65cc4 [IR] Let IRBuilder's CreateVectorSplat/CreateShuffleVector use poison as placeholder
This patch updates IRBuilder to create insertelement/shufflevector using poison as a placeholder.

Reviewed By: nikic

Differential Revision: https://reviews.llvm.org/D93793
2020-12-30 04:21:04 +09:00
Simon Pilgrim
119e4550dd [SLPVectorizer][X86] Remove unused check-prefixes 2020-11-08 14:03:55 +00:00
Amara Emerson
322d0afd87 [llvm][mlir] Promote the experimental reduction intrinsics to be first class intrinsics.
This change renames the intrinsics to not have "experimental" in the name.

The autoupgrader will handle legacy intrinsics.

Relevant ML thread: http://lists.llvm.org/pipermail/llvm-dev/2020-April/140729.html

Differential Revision: https://reviews.llvm.org/D88787
2020-10-07 10:36:44 -07:00
Sanjay Patel
e50059f6b6 [x86] form reduction intrinsics from vectorizers instead of raw IR
Motivating examples are seen in the PhaseOrdering tests based on:
https://bugs.llvm.org/show_bug.cgi?id=43953#c2 - if we have
intrinsics there, some pass can fold them.

The intrinsics are still named "experimental" at this point, but
if there is no fallout from this patch, that will be a good
indicator that it is safe to finalize them.

Differential Revision: https://reviews.llvm.org/D80867
2020-06-05 12:38:49 -04:00
Alexey Bataev
8b1eeafb91 [SLP] Fix for PR31847: Assertion failed: (isLoopInvariant(Operands[i], L) && "SCEVAddRecExpr operand is not loop-invariant!")
Initially SLP vectorizer replaced all going-to-be-vectorized
instructions with Undef values. It may break ScalarEvaluation and may
cause a crash.
Reworked SLP vectorizer so that it does not replace vectorized
instructions by UndefValue anymore. Instead vectorized instructions are
marked for deletion inside if BoUpSLP class and deleted upon class
destruction.

Reviewers: mzolotukhin, mkuper, hfinkel, RKSimon, davide, spatel

Subscribers: RKSimon, Gerolf, anemet, hans, majnemer, llvm-commits, sanjoy

Differential Revision: https://reviews.llvm.org/D29641

llvm-svn: 373166
2019-09-29 14:18:06 +00:00
Jordan Rupprecht
f98d2c099a Revert [SLP] Fix for PR31847: Assertion failed: (isLoopInvariant(Operands[i], L) && "SCEVAddRecExpr operand is not loop-invariant!")
This reverts r372626 (git commit 6a278d9073bdc158d31d4f4b15bbe34238f22c18)

llvm-svn: 373019
2019-09-26 22:09:17 +00:00
Alexey Bataev
6a278d9073 [SLP] Fix for PR31847: Assertion failed: (isLoopInvariant(Operands[i], L) && "SCEVAddRecExpr operand is not loop-invariant!")
Summary:
Initially SLP vectorizer replaced all going-to-be-vectorized
instructions with Undef values. It may break ScalarEvaluation and may
cause a crash.
Reworked SLP vectorizer so that it does not replace vectorized
instructions by UndefValue anymore. Instead vectorized instructions are
marked for deletion inside if BoUpSLP class and deleted upon class
destruction.

Reviewers: mzolotukhin, mkuper, hfinkel, RKSimon, davide, spatel

Subscribers: RKSimon, Gerolf, anemet, hans, majnemer, llvm-commits, sanjoy

Differential Revision: https://reviews.llvm.org/D29641

llvm-svn: 372626
2019-09-23 16:25:03 +00:00
Eric Christopher
cee313d288 Revert "Temporarily Revert "Add basic loop fusion pass.""
The reversion apparently deleted the test/Transforms directory.

Will be re-reverting again.

llvm-svn: 358552
2019-04-17 04:52:47 +00:00
Eric Christopher
a863435128 Temporarily Revert "Add basic loop fusion pass."
As it's causing some bot failures (and per request from kbarton).

This reverts commit r358543/ab70da07286e618016e78247e4a24fcb84077fda.

llvm-svn: 358546
2019-04-17 02:12:23 +00:00
Simon Pilgrim
6f96795b88 [SLPVectorizer] Merge reorderAltShuffleOperands into reorderInputsAccordingToOpcode
As discussed on D59738, this generalizes reorderInputsAccordingToOpcode to handle multiple + non-commutative instructions so we can get rid of reorderAltShuffleOperands and make use of the extra canonicalizations that reorderInputsAccordingToOpcode brings.

Differential Revision: https://reviews.llvm.org/D59784

llvm-svn: 356939
2019-03-25 20:05:27 +00:00
Simon Pilgrim
ff3abef395 [SLPVectorizer] reorderInputsAccordingToOpcode - remove non-Instruction canonicalization
Remove attempts to commute non-Instructions to the LHS - the codegen changes appear to rely on chance more than anything else and also have a tendency to fight existing instcombine canonicalization which moves constants to the RHS of commutable binary ops.

This is prep work towards:
(a) reusing reorderInputsAccordingToOpcode for alt-shuffles and removing the similar reorderAltShuffleOperands
(b) improving reordering to optimized cases with commutable and non-commutable instructions to still find splat/consecutive ops.

Differential Revision: https://reviews.llvm.org/D59738

llvm-svn: 356913
2019-03-25 15:53:55 +00:00
Alexey Bataev
18809a6bbb [SLP] Fix PR40310: The reduction nodes should stay scalar.
Summary:
Sometimes the SLP vectorizer tries to vectorize the horizontal reduction
nodes during regular vectorization. This may happen inside of the loops,
when there are some vectorizable PHIs. Patch fixes this by checking if
the node is the reduction node and thus it must not be vectorized, it must
be gathered.

Reviewers: RKSimon, spatel, hfinkel, fedor.sergeev

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D56783

llvm-svn: 351349
2019-01-16 15:39:52 +00:00
Simon Pilgrim
924f98e579 Add common check prefix. NFCI.
llvm-svn: 348265
2018-12-04 14:32:42 +00:00
Simon Pilgrim
102854f4d4 [TTI] Reduction costs only need to include a single extract element cost (REAPPLIED)
We were adding the entire scalarization extraction cost for reductions, which returns the total cost of extracting every element of a vector type.

For reductions we don't need to do this - we just need to extract the 0'th element after the reduction pattern has completed.

Fixes PR37731

Rebased and reapplied after being reverted in rL347541 due to PR39774 - which was fixed by D54955/rL347759 and D55017/rL347997

Differential Revision: https://reviews.llvm.org/D54585

llvm-svn: 348076
2018-12-01 14:18:31 +00:00
Alexey Bataev
3689747619 [SLP]PR39774: Update references of the replaced external instructions.
Summary:
An additional fix for PR39774. Need to update the references for the
RedcutionRoot instruction when it is replaced during the vectorization
phase to avoid compiler crash on reduction vectorization.

Reviewers: RKSimon, spatel

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D55017

llvm-svn: 347997
2018-11-30 15:14:20 +00:00
Alexey Bataev
579c2d9d64 [SLP]Fix PR39774: Set ReductionRoot if the original instruction is vectorized.
Summary:
If the original reduction root instruction was vectorized, it might be
removed from the tree. It means that the insertion point may become
invalidated and the whole vectorization of the reduction leads to the
incorrect output result.
The ReductionRoot instruction must be marked as externally used so it
could not be removed. Otherwise it might cause inconsistency with the
cost model and we may end up with too optimistic optimization.

Reviewers: RKSimon, spatel, hfinkel, mkuper

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D54955

llvm-svn: 347759
2018-11-28 14:34:11 +00:00