Switch to C++14 standard method as llvm::make_unique has been removed (
https://reviews.llvm.org/D66259). Also mark some targets as c++14 to ease next
integrates.
PiperOrigin-RevId: 263953918
There are currently several different terms used to refer to a parent IR unit in 'get' methods: getParent/getEnclosing/getContaining. This cl standardizes all of these methods to use 'getParent*'.
PiperOrigin-RevId: 262680287
The loop parallelism detection utility only collects the affine.load and
affine.store operations appearing inside the loop to analyze the access
patterns for the absence of dependences. However, any operation, including
unregistered operations, can appear in a body of an affine loop. If such
operation has side effects, the result of parallelism analysis is incorrect.
Conservatively assume affine loops are not parallel in presence of operations
other than affine.load, affine.store, affine.for, affine.terminator that may
have side effects.
This required to update the loop-fusion unit test that relies on parallelism
analysis and was exercising loop fusion in presence of an unregistered
operation.
PiperOrigin-RevId: 259560935
In most places, this is just a name change (with the exception of affine.dma_start swapping the operand positions of its tag memref and num_elements operands).
Significant code changes occur here:
*) Vectorization: LoopAnalysis.cpp, Vectorize.cpp
*) Affine Transforms: Transforms/Utils/Utils.cpp
PiperOrigin-RevId: 256395088
Extract common methods into ShapedType.
Simplify methods.
Remove some extraneous asserts.
Replace sentinel value with a helper method to check the same.
--
PiperOrigin-RevId: 250945261
*) Factors slice union computation out of LoopFusion into Analysis/Utils (where other iteration slice utilities exist).
*) Generalizes slice union computation to take the union of slices computed on all loads/stores pairs between source and destination loop nests.
*) Fixes a bug in FlatAffineConstraints::addSliceBounds where redundant constraints were added.
*) Takes care of a TODO to expose FlatAffineConstraints::mergeAndAlignIds as a public method.
--
PiperOrigin-RevId: 250561529
* dyn_cast_or_null
- This will first check if the operation is null before trying to 'dyn_cast':
Value *v = ...;
if (auto forOp = dyn_cast_or_null<AffineForOp>(v->getDefiningOp()))
...
* isa_nonnull
- This will first check if the pointer is null before trying to 'isa':
Value *v = ...;
if (isa_nonnull<AffineForOp>(v->getDefiningOp());
...
--
PiperOrigin-RevId: 242171343
inherited constructors, which is cleaner and means you can now use DimOp()
to get a null op, instead of having to use Instruction::getNull<DimOp>().
This removes another 200 lines of code.
PiperOrigin-RevId: 240068113
This also eliminates some incorrect reinterpret_cast logic working around it, and numerous const-incorrect issues (like block argument iteration).
PiperOrigin-RevId: 239712029
This eliminate ConstOpPointer (but keeps OpPointer for now) by making OpPointer
implicitly launder const in a const incorrect way. It will eventually go away
entirely, this is a progressive step towards the new const model.
PiperOrigin-RevId: 239512640
- this is really not a hard error; emit a warning instead (for inability to compute
footprint due to the union failing due to unimplemented cases)
- remove a misleading warning from LoopFusion.cpp
PiperOrigin-RevId: 238118711
- fix for getConstantBoundOnDimSize: floordiv -> ceildiv for extent
- make getConstantBoundOnDimSize also return the identifier upper bound
- fix unionBoundingBox to correctly use the divisor and upper bound identified by
getConstantBoundOnDimSize
- deal with loop step correctly in addAffineForOpDomain (covers most cases now)
- fully compose bound map / operands and simplify/canonicalize before adding
dim/symbol to FlatAffineConstraints; fixes false positives in -memref-bound-check; add
test case there
- expose mlir::isTopLevelSymbol from AffineOps
PiperOrigin-RevId: 238050395
Adds utility to convert slice bounds to a FlatAffineConstraints representation.
Adds utility to FlatAffineConstraints to promote loop IV symbol identifiers to dim identifiers.
PiperOrigin-RevId: 236973261
- This change only impacts the cost model for fusion, given the way
addSliceBounds was being used. It so happens that the output in spite of this
CL's fix is the same; however, the assertions added no longer fail. (an
invalid/inconsistent memref region was being used earlier).
PiperOrigin-RevId: 236405030
This CL changes dialect op source files (.h, .cpp, .td) to follow the following
convention:
<full-dialect-name>/<dialect-namespace>Ops.{h|cpp|td}
Builtin and standard dialects are specially treated, though. Both of them do
not have dialect namespace; the former is still named as BuiltinOps.* and the
latter is named as Ops.*.
Purely mechanical. NFC.
PiperOrigin-RevId: 236371358
- detect all parallel loops based on dep information and mark them with a
"parallel" attribute
- add mlir::isLoopParallel(OpPointer<AffineForOp> ...), and refactor an existing method
to use that (reuse some code from @andydavis (cl/236007073) for this)
- a simple/meaningful way to test memref dep test as well
Ex:
$ mlir-opt -detect-parallel test/Transforms/parallelism-detection.mlir
#map1 = ()[s0] -> (s0)
func @foo(%arg0: index) {
%0 = alloc() : memref<1024x1024xvector<64xf32>>
%1 = alloc() : memref<1024x1024xvector<64xf32>>
%2 = alloc() : memref<1024x1024xvector<64xf32>>
for %i0 = 0 to %arg0 {
for %i1 = 0 to %arg0 {
for %i2 = 0 to %arg0 {
%3 = load %0[%i0, %i2] : memref<1024x1024xvector<64xf32>>
%4 = load %1[%i2, %i1] : memref<1024x1024xvector<64xf32>>
%5 = load %2[%i0, %i1] : memref<1024x1024xvector<64xf32>>
%6 = mulf %3, %4 : vector<64xf32>
%7 = addf %5, %6 : vector<64xf32>
store %7, %2[%i0, %i1] : memref<1024x1024xvector<64xf32>>
} {parallel: false}
} {parallel: true}
} {parallel: true}
return
}
PiperOrigin-RevId: 236367368
*) Breaks fusion pass into multiple sub passes over nodes in data dependence graph:
- first pass fuses single-use producers into their unique consumer.
- second pass enables fusing for input-reuse by fusing sibling nodes which read from the same memref, but which do not share dependence edges.
- third pass fuses remaining producers into their consumers (Note that the sibling fusion pass may have transformed a producer with multiple uses into a single-use producer).
*) Fusion for input reuse is enabled by computing a sibling node slice using the load/load accesses to the same memref, and fusion safety is guaranteed by checking that the sibling node memref write region (to a different memref) is preserved.
*) Enables output vector and output matrix computations from KFAC patches-second-moment operation to fuse into a single loop nest and reuse input from the image patches operation.
*) Adds a generic loop utilitiy for finding all sequential loops in a loop nest.
*) Adds and updates unit tests.
PiperOrigin-RevId: 236350987
- add a method to merge and align the spaces (identifiers) of two
FlatAffineConstraints (both get dimension-wise and symbol-wise unique
columns)
- this completes several TODOs, gets rid of previous assumptions/restrictions
in composeMap, unionBoundingBox, and reuses common code
- remove previous workarounds / duplicated funcitonality in
FlatAffineConstraints::composeMap and unionBoundingBox, use mergeAlignIds
from both
PiperOrigin-RevId: 236320581
Analysis - NFC
- refactor AffineExprFlattener (-> SimpleAffineExprFlattener) so that it
doesn't depend on FlatAffineConstraints, and so that FlatAffineConstraints
could be moved out of IR/; the simplification that the IR needs for
AffineExpr's doesn't depend on FlatAffineConstraints
- have AffineExprFlattener derive from SimpleAffineExprFlattener to use for
all Analysis/Transforms purposes; override addLocalFloorDivId in the derived
class
- turn addAffineForOpDomain into a method on FlatAffineConstraints
- turn AffineForOp::getAsValueMap into an AffineValueMap ctor
PiperOrigin-RevId: 235283610
generation pass to make it drop certain assumptions, complete TODOs.
- multiple fixes for getMemoryFootprintBytes
- pass loopDepth correctly from getMemoryFootprintBytes()
- use union while computing memory footprints
- bug fixes for addAffineForOpDomain
- take into account loop step
- add domains of other loop IVs in turn that might have been used in the bounds
- dma-generate: drop assumption of "non-unit stride loops being tile space loops
and skipping those and recursing to inner depths"; DMA generation is now purely
based on available fast mem capacity and memory footprint's calculated
- handle memory region compute failures/bailouts correctly from dma-generate
- loop tiling cleanup/NFC
- update some debug and error messages to use emitNote/emitError in
pipeline-data-transfer pass - NFC
PiperOrigin-RevId: 234245969
- determine symbols for the memref region correctly
- this wasn't exposed earlier since we didn't have any test cases where the
portion of the nest being DMAed for was non-hyperrectangular (i.e., bounds of
one IV depending on other IVs within that part)
PiperOrigin-RevId: 233493872
*) Adds parameter to public API of MemRefRegion::compute for passing in the slice loop bounds to compute the memref region of the loop nest slice.
*) Exposes public method MemRefRegion::getRegionSize for computing the size of the memref region in bytes.
PiperOrigin-RevId: 232706165
* AffineStructures has moved to IR.
* simplifyAffineExpr/simplifyAffineMap/getFlattenedAffineExpr have moved to IR.
* makeComposedAffineApply/fullyComposeAffineMapAndOperands have moved to AffineOps.
* ComposeAffineMaps is replaced by AffineApplyOp::canonicalize and deleted.
PiperOrigin-RevId: 232586468
- use getAccessMap() instead of repeating it
- fold getMemRefRegion into MemRefRegion ctor (more natural, avoid heap
allocation and unique_ptr where possible)
- change extractForInductionVars - MutableArrayRef -> ArrayRef for the
arguments. Since the method is just returning copies of 'Value *', the client
can't mutate the pointers themselves; it's fine to mutate the 'Value''s
themselves, but that doesn't mutate the pointers to those.
- change the way extractForInductionVars returns (see b/123437690)
PiperOrigin-RevId: 232359277
loops), (2) take into account fast memory space capacity and lower 'dmaDepth'
to fit, (3) add location information for debug info / errors
- change dma-generate pass to work on blocks of instructions (start/end
iterators) instead of 'for' loops; complete TODOs - allows DMA generation for
straightline blocks of operation instructions interspersed b/w loops
- take into account fast memory capacity: check whether memory footprint fits
in fastMemoryCapacity parameter, and recurse/lower the depth at which DMA
generation is performed until it does fit in the provided memory
- add location information to MemRefRegion; any insufficient fast memory
capacity errors or debug info w.r.t dma generation shows location information
- allow DMA generation pass to be instantiated with a fast memory capacity
option (besides command line flag)
- change getMemRefRegion to return unique_ptr's
- change getMemRefFootprintBytes to work on a 'Block' instead of 'ForInst'
- other helper methods; add postDomInstFilter option for
replaceAllMemRefUsesWith; drop forInst->walkOps, add Block::walkOps methods
Eg. output
$ mlir-opt -dma-generate -dma-fast-mem-capacity=1 /tmp/single.mlir
/tmp/single.mlir:9:13: error: Total size of all DMA buffers' for this block exceeds fast memory capacity
for %i3 = (d0) -> (d0)(%i1) to (d0) -> (d0 + 32)(%i1) {
^
$ mlir-opt -debug-only=dma-generate -dma-generate -dma-fast-mem-capacity=400 /tmp/single.mlir
/tmp/single.mlir:9:13: note: 8 KiB of DMA buffers in fast memory space for this block
for %i3 = (d0) -> (d0)(%i1) to (d0) -> (d0 + 32)(%i1) {
PiperOrigin-RevId: 232297044
Addresses b/122486036
This CL addresses some leftover crumbs in AffineMap and IntegerSet by removing
the Null method and cleaning up the constructors.
As the ::Null uses were tracked down, opportunities appeared to untangle some
of the Parsing logic and make it explicit where AffineMap/IntegerSet have
ambiguous syntax. Previously, ambiguous cases were hidden behind the implicit
pointer values of AffineMap* and IntegerSet* that were passed as function
parameters. Depending the values of those pointers one of 3 behaviors could
occur.
This parsing logic convolution is one of the rare cases where I would advocate
for code duplication. The more proper fix would be to make the syntax
unambiguous or to allow some lookahead.
PiperOrigin-RevId: 231058512
- introduce a way to compute union using symbolic rectangular bounding boxes
- handle multiple load/store op's to the same memref by taking a union of the regions
- command-line argument to provide capacity of the fast memory space
- minor change to replaceAllMemRefUsesWith to not generate affine_apply if the
supplied index remap was identity
PiperOrigin-RevId: 230848185
- update fusion cost model to fuse while tolerating a certain amount of redundant
computation; add cl option -fusion-compute-tolerance
evaluate memory footprint and intermediate memory reduction
- emit debug info from -loop-fusion showing what was fused and why
- introduce function to compute memory footprint for a loop nest
- getMemRefRegion readability update - NFC
PiperOrigin-RevId: 230541857
- the size of the private memref created for the slice should be based on
the memref region accessed at the depth at which the slice is being
materialized, i.e., symbolic in the outer IVs up until that depth, as opposed
to the region accessed based on the entire domain.
- leads to a significant contraction of the temporary / intermediate memref
whenever the memref isn't reduced to a single scalar (through store fwd'ing).
Other changes
- update to promoteIfSingleIteration - avoid introducing unnecessary identity
map affine_apply from IV; makes it much easier to write and read test cases
and pass output for all passes that use promoteIfSingleIteration; loop-fusion
test cases become much simpler
- fix replaceAllMemrefUsesWith bug that was exposed by the above update -
'domInstFilter' could be one of the ops erased due to a memref replacement in
it.
- fix getConstantBoundOnDimSize bug: a division by the coefficient of the identifier was
missing (the latter need not always be 1); add lbFloorDivisors output argument
- rename getBoundingConstantSizeAndShape -> getConstantBoundingSizeAndShape
PiperOrigin-RevId: 230405218
*) Adds support for fusing into consumer loop nests with multiple loads from the same memref.
*) Adds support for reducing slice loop trip count by projecting out destination loop IVs greater than destination loop depth.
*) Removes dependence on src loop depth and simplifies cost model computation.
PiperOrigin-RevId: 229575126
*) LoopFusion: Adds fusion cost function which compares the cost of the fused loop nest, with the cost of the two unfused loop nests to determine if it is profitable to fuse the candidate loop nests. The fusion cost function is run for various combinations for src/dst loop depths attempting find the minimum cost setting for src/dst loop depths which does not increase the computational cost when the loop nests are fused. Combinations of src/dst loop depth are evaluated attempting to maximize loop depth (i.e. take a bigger computation slice from the source loop nest, and insert it deeper in the destination loop nest for better locality).
*) LoopFusion: Adds utility to compute op instance count for loop nests, sliced loop nests, and to compute the cost of a loop nest fused with another sliced loop nest.
*) LoopFusion: canonicalizes slice bound AffineMaps (and updates related tests).
*) Analysis::Utils: Splits getBackwardComputationSlice into two functions: one which calculates and returns the slice loop bounds for analysis by LoopFusion, and the other for insertion of the computation slice (ones fusion has calculated the min-cost src/dst loop depths).
*) Test: Adds multiple unit tests to test the new functionality.
PiperOrigin-RevId: 229219757
This CL is the 6th and last on the path to simplifying AffineMap composition.
This removes `AffineValueMap::forwardSubstitutions` and replaces it by simple
calls to `fullyComposeAffineMapAndOperands`.
PiperOrigin-RevId: 228962580
clients. Let's re-add it in the future if there is ever a reason to. NFC.
Unrelatedly, add a use of a variable to unbreak the non-assert build.
PiperOrigin-RevId: 228284026
- refactor toAffineFromEq and the code surrounding it; refactor code into
FlatAffineConstraints::getSliceBounds
- add FlatAffineConstraints methods to detect identifiers as mod's and div's of other
identifiers
- add FlatAffineConstraints::getConstantLower/UpperBound
- Address b/122118218 (don't assert on invalid fusion depths cmdline flags -
instead, don't do anything; change cmdline flags
src-loop-depth -> fusion-src-loop-depth
- AffineExpr/Map print method update: don't fail on null instances (since we have
a wrapper around a pointer, it's avoidable); rationale: dump/print methods should
never fail if possible.
- Update memref-dataflow-opt to add an optimization to avoid a unnecessary call to
IsRangeOneToOne when it's trivially going to be true.
- Add additional test cases to exercise the new support
- update a few existing test cases since the maps are now generated uniformly with
all destination loop operands appearing for the backward slice
- Fix projectOut - fix wrong range for getBestElimCandidate.
- Fix for getConstantBoundOnDimSize() - didn't show up in any test cases since
we didn't have any non-hyperrectangular ones.
PiperOrigin-RevId: 228265152
- when SSAValue/MLValue existed, code at several places was forced to create additional
aggregate temporaries of SmallVector<SSAValue/MLValue> to handle the conversion; get
rid of such redundant code
- use filling ctors instead of explicit loops
- for smallvectors, change insert(list.end(), ...) -> append(...
- improve comments at various places
- turn getMemRefAccess into MemRefAccess ctor and drop duplicated
getMemRefAccess. In the next CL, provide getAccess() accessors for load,
store, DMA op's to return a MemRefAccess.
PiperOrigin-RevId: 228243638
- this is CL 1/2 that does a clean up and gets rid of one limitation in an
underlying method - as a result, fusion works for more cases.
- fix bugs/incomplete impl. in toAffineMapFromEq
- fusing across rank changing reshapes for example now just works
For eg. given a rank 1 memref to rank 2 memref reshape (64 -> 8 x 8) like this,
-loop-fusion -memref-dataflow-opt now completely fuses and inlines/store-forward
to get rid of the temporary:
INPUT
// Rank 1 -> Rank 2 reshape
for %i0 = 0 to 64 {
%v = load %A[%i0]
store %v, %B[%i0 floordiv 8, i0 mod 8]
}
for %i1 = 0 to 8
for %i2 = 0 to 8
%w = load %B[%i1, i2]
"foo"(%w) : (f32) -> ()
OUTPUT
$ mlir-opt -loop-fusion -memref-dataflow-opt fuse_reshape.mlir
#map0 = (d0, d1) -> (d0 * 8 + d1)
mlfunc @fuse_reshape(%arg0: memref<64xf32>) {
for %i0 = 0 to 8 {
for %i1 = 0 to 8 {
%0 = affine_apply #map0(%i0, %i1)
%1 = load %arg0[%0] : memref<64xf32>
"foo"(%1) : (f32) -> ()
}
}
}
AFAIK, there is no polyhedral tool / compiler that can perform such fusion -
because it's not really standard loop fusion, but possible through a
generalized slicing-based approach such as ours.
PiperOrigin-RevId: 227918338
- introduce PostDominanceInfo in the right/complete way and use that for post
dominance check in store-load forwarding
- replace all uses of Analysis/Utils::dominates/properlyDominates with
DominanceInfo::dominates/properlyDominates
- drop all redundant copies of dominance methods in Analysis/Utils/
- in pipeline-data-transfer, replace dominates call with a much less expensive
check; similarly, substitute dominates() in checkMemRefAccessDependence with
a simpler check suitable for that context
- fix a bug in properlyDominates
- improve doc for 'for' instruction 'body'
PiperOrigin-RevId: 227320507
- the load/store forwarding relies on memref dependence routines as well as
SSA/dominance to identify the memref store instance uniquely supplying a value
to a memref load, and replaces the result of that load with the value being
stored. The memref is also deleted when possible if only stores remain.
- add methods for post dominance for MLFunction blocks.
- remove duplicated getLoopDepth/getNestingDepth - move getNestingDepth,
getMemRefAccess, getNumCommonSurroundingLoops into Analysis/Utils (were
earlier static)
- add a helper method in FlatAffineConstraints - isRangeOneToOne.
PiperOrigin-RevId: 227252907
requires enhancing DominanceInfo to handle the structure of an ML function,
which is required anyway. Along the way, this also fixes a const correctness
problem with Instruction::getBlock().
This is step 24/n towards merging instructions and statements.
PiperOrigin-RevId: 227228900
consistent and moving the using declarations over. Hopefully this is the last
truly massive patch in this refactoring.
This is step 21/n towards merging instructions and statements, NFC.
PiperOrigin-RevId: 227178245
The last major renaming is Statement -> Instruction, which is why Statement and
Stmt still appears in various places.
This is step 19/n towards merging instructions and statements, NFC.
PiperOrigin-RevId: 227163082
StmtResult -> InstResult, StmtOperand -> InstOperand, and remove the old names.
This is step 17/n towards merging instructions and statements, NFC.
PiperOrigin-RevId: 227121537
FuncBuilder class. Also rename SSAValue.cpp to Value.cpp
This is step 12/n towards merging instructions and statements, NFC.
PiperOrigin-RevId: 227067644
is the new base of the SSA value hierarchy. This CL also standardizes all the
nomenclature and comments to use 'Value' where appropriate. This also eliminates a large number of cast<MLValue>(x)'s, which is very soothing.
This is step 11/n towards merging instructions and statements, NFC.
PiperOrigin-RevId: 227064624
making it more similar to the CFG side of things. It is true that in a deeply
nested case that this is not a guaranteed O(1) time operation, and that 'get'
could lead compiler hackers to think this is cheap, but we need to merge these
and we can look into solutions for this in the future if it becomes a problem
in practice.
This is step 9/n towards merging instructions and statements, NFC.
PiperOrigin-RevId: 226983931
StmtBlock. This is more consistent with IfStmt and also conceptually makes
more sense - a forstmt "isn't" its body, it contains its body.
This is step 1/N towards merging BasicBlock and StmtBlock. This is required
because in the new regime StmtBlock will have a use list (just like BasicBlock
does) of operands, and ForStmt already has a use list for its induction
variable.
This is a mechanical patch, NFC.
PiperOrigin-RevId: 226684158