Generalized the cost model estimation. Improved cost model estimation
for repeated scalars (no need to count their cost anymore), improved
cost model for extractelement instructions.
cpu2017
511.povray_r 0.57
520.omnetpp_r -0.98
521.wrf_r -0.01
525.x264_r 3.59 <+
526.blender_r -0.12
531.deepsjeng_r -0.07
538.imagick_r -1.42
Geometric mean: 0.21
Differential Revision: https://reviews.llvm.org/D115757
Generalized the cost model estimation. Improved cost model estimation
for repeated scalars (no need to count their cost anymore), improved
cost model for extractelement instructions.
cpu2017
511.povray_r 0.57
520.omnetpp_r -0.98
521.wrf_r -0.01
525.x264_r 3.59 <+
526.blender_r -0.12
531.deepsjeng_r -0.07
538.imagick_r -1.42
Geometric mean: 0.21
Differential Revision: https://reviews.llvm.org/D115757
When generating masked gathers nodes, SLP vectorizer accounts the cost
of the GEPs for loads as part of the scalar-vector transformation cost
estimation. But it does not do it for vectorized loads/stores, while it
may completely remove some of the GEPs completely. Because of this in
some cases masked gather operation can be much more profitable rather
than regular vectorization (masked-gather cost + vector GEP - scalar
loads + GEPs comparing to vectorized loads - scalar loads).
Added the analysis of the removed scalarGEPs for vectorized load/store nodes for better cost estimation.
Differential Revision: https://reviews.llvm.org/D135282
Need to set the insertpoint for extractelement to point to the first
instruction in the node to avoid possible crash during external uses
combine process. Without it we may endup with the incorrect
transformation.
Differential Revision: https://reviews.llvm.org/D135591
Freeze instruction in some cases makes codegen worse, so need to be very
careful when emitting it. Instead improve analysis in isUndefVector
function to generate mask of unused elements and use it in the analysis.
Differential Revision: https://reviews.llvm.org/D135382
Added analysis for invariant extractelement instructions and improved
detection of the CSE blocks for generated extractelement instructions.
Differential Revision: https://reviews.llvm.org/D135279
In the canonical form of the shuffle the poison/undef operand is the
second operand, the patch tries to emit canonical form for partial
vectorization of the buildvector sequence.
Also, this patch starts emitting freeze instruction for shuffles with undef indices if the second shuffle operan is undef, not poison. It is an initial step to D93818, where undef mask element are treated as returning poison value.
Differential Revision: https://reviews.llvm.org/D134377
Revert rGef89409a59f3b79ae143b33b7d8e6ee6285aa42f "Fix 'unused-lambda-capture' gcc warning. NFCI."
Revert rG926ccfef032d206dcbcdf74ca1e3a9ebf4d1be45 "[SLP] ScalarizationOverheadBuilder - demand all elements for scalarization if the extraction index is unknown / out of bounds"
Revert ScalarizationOverheadBuilder sequence from D134605 - when accumulating extraction costs by Type (instead of specific Value), we are not distinguishing enough when they are coming from the same source or not, and we always just count the cost once. This needs addressing before we can use getScalarizationOverhead properly.
This change updates the costs to make constant pool loads match their actual cost, and adds the broadcast special case to avoid too many regressions. We really need more information about the constants being rematerialized, but this is an incremental improvement.
Differential Revision: https://reviews.llvm.org/D134746
Instead of accumulating all extraction costs separately and then adjusting for repeated subvector extractions, this patch collects all the extractions and then converts to calls to getScalarizationOverhead to improve the accuracy of the costs.
I'm not entirely satisfied with the getExtractWithExtendCost handling yet - this still just adds all the getExtractWithExtendCost costs together - it really needs to be replaced with a "getScalarizationOverheadWithExtend", but that will require further refactoring first.
This replaces my initial attempt in D124769.
Differential Revision: https://reviews.llvm.org/D134605
The mul by constant costmodels handle power-of-2 constants, but not negated-power-of-2, despite the backends handling both.
This patch adds the OperandValueProperties::OP_NegatedPowerOf2 enum and wires it for use for basic mul cost analysis and SLP handling.
Fixes#50778
Differential Revision: https://reviews.llvm.org/D111968
This is the first patch in a series intended for removing flag
-enable-new-pm=0 from lit tests. This is part of a bigger
effort of completely removing legacy code related to legacy
pass manager in favor of currently default new pass manager.
In this patch flag has been removed only from tests where no significant
change has been required because checks has been duplicated for
both PMs.
Reviewed By: fhahn
Differential Revision: https://reviews.llvm.org/D134150
Added the mask and the analysis of the buildvector sequence in the
isUndefVector function, improves codegen and cost estimation.
Metric: SLP.NumVectorInstructions
Program SLP.NumVectorInstructions
results results0 diff
test-suite :: External/SPEC/CFP2017rate/526.blender_r/526.blender_r.test 27362.00 27360.00 -0.0%
Metric: size..text
Program size..text
results results0 diff
test-suite :: External/SPEC/CFP2017rate/508.namd_r/508.namd_r.test 805299.00 806035.00 0.1%
526.blender_r - some extra code is vectorized.
508.namd_r - some extra code is optimized out.
Differential Revision: https://reviews.llvm.org/D133891
This was achieved with an updated version of the 'cost-tables vs llvm-mca' script D103695 (and recent fixes to the bdver2 + alderlake models)
Adding full CostKinds costs are affecting some other tests as they make assumptions about SizeLatency costs, so they need addressing first
These are the worst case generic vector shift costs, where nothing is known about the shift amounts - in particular this should stop us using the default sizelatency cost of 1 for so many pre-AVX2 vector shifts that can often actually expand during lowering to +20 uops, just for 128-bit vectors, resulting in some horrible inline/unroll decisions.
This was achieved with an updated version of the 'cost-tables vs llvm-mca' script D103695 (I'll update the patch soon for reference)
Adding the pre-header to CSEBlocks ensures instructions are CSE'd even
after hoisting.
This was original discovered by @atrick a while ago.
Reviewed By: ABataev
Differential Revision: https://reviews.llvm.org/D133649
If the reused scalars are clustered, i.e. each part of the reused mask
contains all elements of the original scalars exactly once, we can
reorder those clusters to improve the whole ordering of of the clustered
vectors.
Differential Revision: https://reviews.llvm.org/D133524
Need either follow the original order of the operands for bool logical
ops, or emit freeze instruction to avoid poison propagation.
Differential Revision: https://reviews.llvm.org/D126877
The pointer operands for the ScatterVectorize node may contain
non-instruction values and they are not checked for "already being
vectorized". Need to check that such pointers are already vectorized and
gather them instead of trying to build vectorize node to avoid compiler
crash.
Differential Revision: https://reviews.llvm.org/D132949
This patch changes order of searching for reductions vs other vectorization possibilities.
The idea is if we do not match a reduction it won't be harmful for further attempts to
find vectorizable operations on a vector build sequences. But doing it in the opposite
order we have good chance to ruin opportunity to match a reduction later.
We also don't want to try vectorizing binary operations too early as 2-way vectorization
may effectively prohibit wider ones leading to producing less effective code.
Differential Revision: https://reviews.llvm.org/D132590
Add test cases for AArch64 that show over-eager SLP vectorization on
AArch64, where keeping the things scalar allows efficient lowering using
scalar fmas.
When estimating the cost of the in-tree vectorized scalars in
buildvector sequences, need to take into account the vectorized
insertelement instruction. The top of the buildvector seuences is the
topmost vectorized insertelement instruction, because it will have
> than 1 use after the vectorization.
For the affected test case improves througput from 21 to 16 (per
llvm-mca).
Differential Revision: https://reviews.llvm.org/D132740
This change implements a TTI query with the goal of disabling slp vectorization on RISCV. The current default configuration disables SLP already, but its current tied to the ability to lower fixed length vectors. Over in D131508, I want to enable fixed length vectors for purposes of LoopVectorizer, but preliminary analysis has revealed a couple of SLP specific issues we need to resolve before enabling it by default. This change exists to allow us to enable LV without SLP.
Differential Revision: https://reviews.llvm.org/D132680
