Files
llvm/mlir/lib/Dialect/Linalg/Transforms/Transforms.cpp
2023-02-08 18:39:34 -08:00

1322 lines
55 KiB
C++

//===- Transforms.cpp - Linalg transformations as patterns ----------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements logic and helpers to expose Linalg transforms as rewrite
// patterns.
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/Linalg/Transforms/Transforms.h"
#include "mlir/Dialect/Affine/IR/AffineOps.h"
#include "mlir/Dialect/Arith/IR/Arith.h"
#include "mlir/Dialect/Func/IR/FuncOps.h"
#include "mlir/Dialect/Linalg/IR/Linalg.h"
#include "mlir/Dialect/Linalg/Transforms/HoistPadding.h"
#include "mlir/Dialect/Linalg/Utils/Utils.h"
#include "mlir/Dialect/SCF/Transforms/Transforms.h"
#include "mlir/Dialect/Tensor/IR/Tensor.h"
#include "mlir/Dialect/Tensor/IR/TensorTilingInterfaceImpl.h"
#include "mlir/Dialect/Tensor/Utils/Utils.h"
#include "mlir/Dialect/Utils/IndexingUtils.h"
#include "mlir/Dialect/Utils/StaticValueUtils.h"
#include "mlir/Dialect/Utils/StructuredOpsUtils.h"
#include "mlir/Dialect/Vector/IR/VectorOps.h"
#include "mlir/IR/AffineExpr.h"
#include "mlir/IR/Matchers.h"
#include "mlir/Pass/Pass.h"
#include "mlir/Support/LLVM.h"
#include "mlir/Transforms/GreedyPatternRewriteDriver.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/ADT/TypeSwitch.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include <type_traits>
#include <utility>
#define DEBUG_TYPE "linalg-transforms"
using namespace mlir;
using namespace mlir::linalg;
#define DBGS() (llvm::dbgs() << "[" DEBUG_TYPE << "]: ")
#define DBGSNL() (llvm::dbgs() << "\n")
//===----------------------------------------------------------------------===//
// Transformations exposed as rewrite patterns.
//===----------------------------------------------------------------------===//
LinalgTilingOptions &
mlir::linalg::LinalgTilingOptions::setTileSizes(ArrayRef<int64_t> ts) {
assert(!tileSizeComputationFunction && "tile sizes already set");
SmallVector<int64_t, 4> tileSizes(ts.begin(), ts.end());
tileSizeComputationFunction = [tileSizes](OpBuilder &b, Operation *op) {
OpBuilder::InsertionGuard guard(b);
b.setInsertionPointToStart(
&op->getParentOfType<func::FuncOp>().getBody().front());
return llvm::to_vector<4>(map_range(tileSizes, [&](int64_t s) {
Value v = b.create<arith::ConstantIndexOp>(op->getLoc(), s);
return v;
}));
};
return *this;
}
/// Pad the `opOperand` in the `paddingDimensions` using the padding value and
/// the nofold flag found in `paddingValues` and `packPaddings`, respectively.
/// Exit early and return the `opOperand` value if the shape dimensions that
/// match `paddingDimensions` have a static size and the nofold flag is not set.
/// Otherwise, try to pad the shape dimensions that match the iterator
/// dimensions `paddingDimensions` and return the tensor::PadOp result if
/// padding succeeds or failure otherwise.
static FailureOr<Value> padOperandToSmallestStaticBoundingBox(
OpBuilder &b, linalg::LinalgOp opToPad, OpOperand *opOperand,
ArrayRef<int64_t> paddingDimensions, ArrayRef<Attribute> paddingValues,
ArrayRef<bool> packPaddings) {
AffineMap indexingMap = opToPad.getMatchingIndexingMap(opOperand);
ArrayRef<int64_t> shape = opToPad.getShape(opOperand);
// Collect the shape dimension that are a function of the `paddingDimensions`.
llvm::SmallDenseSet<int64_t> shapeDimsToPad;
for (int64_t dim : paddingDimensions)
for (const auto &en : enumerate(indexingMap.getResults()))
if (en.value().isFunctionOfDim(dim))
shapeDimsToPad.insert(en.index());
// Return the unpadded operand if padding to a static shape is not needed and
// if the nofold flag is not set.
bool nofold = opOperand->getOperandNumber() < packPaddings.size()
? packPaddings[opOperand->getOperandNumber()]
: false;
bool hasStaticShape = llvm::none_of(shapeDimsToPad, [&](int64_t dim) {
return ShapedType::isDynamic(shape[dim]);
});
if (!nofold && hasStaticShape)
return opOperand->get();
// Fail if `paddingValues` specifies no padding value.
if (opOperand->getOperandNumber() >= paddingValues.size())
return failure();
Attribute paddingAttr = paddingValues[opOperand->getOperandNumber()];
Type paddingType = b.getType<NoneType>();
if (auto typedAttr = paddingAttr.dyn_cast<TypedAttr>())
paddingType = typedAttr.getType();
Value paddingValue =
b.create<arith::ConstantOp>(opToPad.getLoc(), paddingType, paddingAttr);
// Follow the use-def chain if `currOpOperand` is defined by a LinalgOp.
OpOperand *currOpOperand = opOperand;
while (auto linalgOp = currOpOperand->get().getDefiningOp<LinalgOp>()) {
OpResult result = currOpOperand->get().cast<OpResult>();
currOpOperand = linalgOp.getDpsInitOperand(result.getResultNumber());
}
// Fail if `currOpOperand` is not defined by an ExtractSliceOp or EmptyOp.
auto sliceOp = currOpOperand->get().getDefiningOp<tensor::ExtractSliceOp>();
auto emptyOp = currOpOperand->get().getDefiningOp<tensor::EmptyOp>();
if (!sliceOp && !emptyOp)
return failure();
llvm::SmallBitVector droppedDims;
SmallVector<OpFoldResult> mixedSizes;
if (sliceOp) {
// Compute the dropped dimensions if `sliceOp` is ranke-reducing.
droppedDims = sliceOp.getDroppedDims();
mixedSizes = sliceOp.getMixedSizes();
}
if (emptyOp) {
mixedSizes = emptyOp.getMixedSizes();
droppedDims.resize(mixedSizes.size());
}
// Upper bound the sizes to obtain a static bounding box.
SmallVector<int64_t> paddedShape(shape.begin(), shape.end());
int64_t shapeIdx = 0;
for (const auto &en : enumerate(mixedSizes)) {
// Skip dropped dimensions.
if (droppedDims.test(en.index()))
continue;
// Skip dimensions that do not require padding.
if (!shapeDimsToPad.contains(shapeIdx)) {
shapeIdx++;
continue;
}
// If the size is an attribute add it directly to `paddedShape`.
if (en.value().is<Attribute>()) {
paddedShape[shapeIdx++] =
en.value().get<Attribute>().dyn_cast<IntegerAttr>().getInt();
continue;
}
// Otherwise, try to compute a constant upper bound for the size value.
FailureOr<int64_t> upperBound =
getConstantUpperBoundForIndex(en.value().get<Value>());
if (failed(upperBound)) {
LLVM_DEBUG(DBGS() << "No constant bounding box can be found for padding");
return failure();
}
paddedShape[shapeIdx++] = *upperBound;
}
assert(shapeIdx == static_cast<int64_t>(shape.size()) &&
"expect the dynamic and static ranks to match");
// Pad the operand to the bounding box defined by `paddedShape`.
auto paddedTensorType = RankedTensorType::get(
paddedShape, getElementTypeOrSelf(opOperand->get()));
return makeComposedPadHighOp(b, opToPad->getLoc(), paddedTensorType,
opOperand->get(), paddingValue, nofold);
}
FailureOr<SmallVector<Value>>
linalg::rewriteAsPaddedOp(OpBuilder &b, LinalgOp opToPad,
ArrayRef<int64_t> paddingDimensions,
ArrayRef<Attribute> paddingValues,
ArrayRef<bool> packPaddings, LinalgOp &paddedOp) {
Location loc = opToPad->getLoc();
// TODO: there are cases where we may still want to pad to larger sizes.
assert(opToPad.hasTensorSemantics() &&
"expected operation to have tensor semantics");
OpBuilder::InsertionGuard g(b);
// Set IP after op because we also take the dims of the original output.
b.setInsertionPointAfter(opToPad);
// Make a copy of the shaped operands and update it.
SmallVector<Value> newOperands;
newOperands.reserve(opToPad->getNumOperands());
for (OpOperand &opOperand : opToPad->getOpOperands()) {
FailureOr<Value> paddedOperand = padOperandToSmallestStaticBoundingBox(
b, opToPad, &opOperand, paddingDimensions, paddingValues, packPaddings);
// Exit if `paddingDimensions` cannot be bounded statically.
if (failed(paddedOperand))
return failure();
newOperands.push_back(*paddedOperand);
}
SmallVector<SmallVector<Value>> reifiedResultShapes;
if (failed(cast<ReifyRankedShapedTypeOpInterface>(opToPad.getOperation())
.reifyResultShapes(b, reifiedResultShapes)))
return failure();
assert(reifiedResultShapes.size() == opToPad->getNumResults() &&
"expected same number of results");
// Clone `opToPad` to operate on the statically padded shapes.
auto resultTensorTypes =
ValueRange(newOperands).take_back(opToPad.getNumDpsInits()).getTypes();
paddedOp = clone(b, opToPad, resultTensorTypes, newOperands);
// Recover the slice out of the new static results. This keeps the original
// linalg op around because it uses the dims of the original results.
SmallVector<Value> paddedSubviewResults;
paddedSubviewResults.reserve(opToPad->getNumResults());
for (const auto &en : llvm::enumerate(paddedOp->getResults())) {
Value paddedResult = en.value();
int64_t resultNumber = en.index();
int64_t rank = paddedResult.getType().cast<RankedTensorType>().getRank();
SmallVector<OpFoldResult> offsets(rank, b.getIndexAttr(0));
SmallVector<OpFoldResult> sizes;
for (Value v : reifiedResultShapes[resultNumber])
sizes.push_back(getAsOpFoldResult(v));
SmallVector<OpFoldResult> strides(rank, b.getIndexAttr(1));
paddedSubviewResults.push_back(b.create<tensor::ExtractSliceOp>(
loc, paddedResult, offsets, sizes, strides));
}
return paddedSubviewResults;
}
/// Try to peel a loop `op` and return the new result.
// TODO: Add support for scf.parallel and affine.for loops.
SmallVector<Value> mlir::linalg::peelLoop(RewriterBase &rewriter,
Operation *op) {
return llvm::TypeSwitch<Operation *, SmallVector<Value, 4>>(op)
.Case<scf::ForOp>([&](scf::ForOp forOp) {
scf::ForOp partialIteration;
if (succeeded(scf::peelAndCanonicalizeForLoop(rewriter, forOp,
partialIteration)))
return partialIteration->getResults();
assert(!partialIteration && "expected that loop was not peeled");
return forOp->getResults();
})
.Default([&](Operation *op) { return op->getResults(); });
}
/// Peel and canonicalize 'loops'.
void mlir::linalg::peelLoops(RewriterBase &rewriter,
ArrayRef<scf::ForOp> loops) {
for (auto loopOp : loops)
peelLoop(rewriter, loopOp);
}
/// Linalg padding pattern.
mlir::linalg::LinalgPaddingPattern::LinalgPaddingPattern(
MLIRContext *context, LinalgPaddingOptions options, PatternBenefit benefit)
: OpInterfaceRewritePattern<LinalgOp>(context, benefit),
options(std::move(options)) {}
FailureOr<LinalgOp>
mlir::linalg::LinalgPaddingPattern::returningMatchAndRewrite(
LinalgOp linalgOp, PatternRewriter &rewriter) const {
if (!linalgOp.hasTensorSemantics())
return failure();
// Pad the operation.
LinalgOp paddedOp;
FailureOr<SmallVector<Value>> newResults =
rewriteAsPaddedOp(rewriter, linalgOp, options.paddingDimensions,
options.paddingValues, options.packPaddings, paddedOp);
if (failed(newResults))
return failure();
// Hoist the padding.
for (const auto &en : enumerate(options.hoistPaddings)) {
if (static_cast<int64_t>(en.index()) >= paddedOp->getNumOperands())
break;
OpOperand &opOperand = paddedOp->getOpOperand(en.index());
auto padOp = opOperand.get().getDefiningOp<tensor::PadOp>();
if (!padOp || en.value() == 0)
continue;
// Fail hoisting if the operand shape is not fully static.
if (llvm::any_of(paddedOp.getShape(&opOperand), ShapedType::isDynamic))
return failure();
tensor::PadOp hoistedOp;
SmallVector<GenericOp> transposeOps;
SmallVector<int64_t> transposeVector =
en.index() < options.transposePaddings.size()
? options.transposePaddings[en.index()]
: SmallVector<int64_t>{};
FailureOr<Value> newResult = hoistPaddingOnTensors(
padOp, en.value(), transposeVector, hoistedOp, transposeOps);
if (failed(newResult))
continue;
rewriter.replaceOp(padOp, *newResult);
}
// Replace the original operation to pad.
rewriter.replaceOp(linalgOp, *newResults);
return paddedOp;
}
LogicalResult mlir::linalg::CopyVectorizationPattern::matchAndRewrite(
memref::CopyOp copyOp, PatternRewriter &rewriter) const {
return vectorizeCopy(rewriter, copyOp);
}
static SmallVector<utils::IteratorType>
getNParallelLoopsAttrs(unsigned nParallelLoops) {
return SmallVector<utils::IteratorType>(nParallelLoops,
utils::IteratorType::parallel);
}
/// Rewrite a tensor::PadOp into a sequence of EmptyOp, FillOp (to
/// initialize with pad_val) and GenericOp (to copy contents).
LogicalResult
PadOpTransformationPattern::matchAndRewrite(tensor::PadOp padOp,
PatternRewriter &rewriter) const {
auto inputShapedType = padOp.getSource().getType().cast<ShapedType>();
auto resultShapedType = padOp.getResult().getType().cast<ShapedType>();
// Bail on non-static shapes.
if (!inputShapedType.hasStaticShape())
return failure();
if (!resultShapedType.hasStaticShape())
return failure();
// Only support padding with a constant for now, i.e. either:
// 1. A BBarg from a different block.
// 2. A value defined outside of the current block.
Block &block = padOp.getRegion().front();
auto yieldOp = cast<tensor::YieldOp>(block.getTerminator());
Value padValue = yieldOp.getValue();
Operation *definingOp = padValue.getDefiningOp();
if (definingOp && definingOp->getBlock() == &block)
return failure();
if (!definingOp && padValue.cast<BlockArgument>().getOwner() == &block)
return failure();
// Create tensor with the padded shape
Location loc = padOp.getLoc();
SmallVector<Value> indices(resultShapedType.getRank(),
rewriter.create<arith::ConstantIndexOp>(loc, 0));
Value emptyTensor = rewriter.create<tensor::EmptyOp>(
loc, resultShapedType.getShape(), resultShapedType.getElementType());
// Initialize tensor with the pad value
Value tmpTensor = rewriter
.create<linalg::FillOp>(loc, ValueRange{padValue},
ValueRange{emptyTensor})
.result();
// Copy original contents into new tensor
// Uses linalg.generic, but could be done with tensor.insert_slice
SmallVector<AffineExpr, 4> outputExprs;
for (unsigned i = 0; i < resultShapedType.getRank(); ++i) {
outputExprs.push_back(getAffineDimExpr(i, rewriter.getContext()) +
padOp.getStaticLow()[i]);
}
SmallVector<AffineMap, 2> transferMaps = {
rewriter.getMultiDimIdentityMap(inputShapedType.getRank()),
AffineMap::get(resultShapedType.getRank(),
/*symbolCount=*/0, outputExprs, rewriter.getContext())};
rewriter.replaceOpWithNewOp<linalg::GenericOp>(
padOp, resultShapedType, padOp.getSource(), tmpTensor, transferMaps,
getNParallelLoopsAttrs(resultShapedType.getRank()),
[&](OpBuilder &nestedBuilder, Location nestedLoc, ValueRange args) {
nestedBuilder.create<linalg::YieldOp>(nestedLoc, args[0]);
});
return success();
}
/// Filling `dest` using FillOp constant padding value if possible.
/// Otherwise, generate a tensor::GenerateOp.
Value GeneralizePadOpPattern::createFillOrGenerateOp(
PatternRewriter &rewriter, tensor::PadOp padOp, Value dest,
const SmallVector<Value> &dynSizes) const {
auto padValue = padOp.getConstantPaddingValue();
if (padValue)
return rewriter.create<FillOp>(padOp.getLoc(), padValue, dest).result();
// Fill could not be optimized: Lower to tensor::GenerateOp with region.
auto generateOp = rewriter.create<tensor::GenerateOp>(
padOp.getLoc(), padOp.getResultType(), dynSizes);
// Copy region to new op.
IRMapping bvm;
padOp.getRegion().cloneInto(&generateOp.getRegion(), bvm);
return generateOp;
}
LogicalResult
GeneralizePadOpPattern::matchAndRewrite(tensor::PadOp padOp,
PatternRewriter &rewriter) const {
// Given an OpFoldResult, return an index-typed value.
auto getIdxValue = [&](OpFoldResult ofr) {
if (auto val = ofr.dyn_cast<Value>())
return val;
return rewriter
.create<arith::ConstantIndexOp>(
padOp.getLoc(), ofr.get<Attribute>().cast<IntegerAttr>().getInt())
.getResult();
};
auto resultType = padOp.getResultType();
// Compute size of EmptyOp. Any combination of static/dynamic is supported.
SmallVector<Value> dynSizes;
SmallVector<int64_t> staticSizes;
for (unsigned dim = 0; dim < resultType.getRank(); ++dim) {
if (resultType.isDynamicDim(dim)) {
auto srcSize = rewriter.createOrFold<tensor::DimOp>(
padOp.getLoc(), padOp.getSource(), dim);
// Add low and high padding value.
auto plusLow = rewriter.createOrFold<arith::AddIOp>(
padOp.getLoc(), srcSize, getIdxValue(padOp.getMixedLowPad()[dim]));
auto plusHigh = rewriter.createOrFold<arith::AddIOp>(
padOp.getLoc(), plusLow, getIdxValue(padOp.getMixedHighPad()[dim]));
dynSizes.push_back(plusHigh);
}
staticSizes.push_back(resultType.getDimSize(dim));
}
// Init tensor and fill it with padding.
Value emptyTensor = rewriter.create<tensor::EmptyOp>(
padOp.getLoc(), staticSizes, resultType.getElementType(), dynSizes);
Value fill = createFillOrGenerateOp(rewriter, padOp, emptyTensor, dynSizes);
// Try optimize the copy of source.
if (optimizeCopyFn && optimizeCopyFn(rewriter, padOp, fill).succeeded())
return success();
// tensor::PadOps cannot be optimized. Generate a InsertSliceOp instead
// for copying the PadOp source.
auto sourceType = padOp.getSourceType();
// Compute size of source of tensor::PadOp.
SmallVector<OpFoldResult> srcSizes;
for (unsigned dim = 0; dim < sourceType.getRank(); ++dim) {
if (sourceType.isDynamicDim(dim)) {
srcSizes.push_back(rewriter.createOrFold<tensor::DimOp>(
padOp.getLoc(), padOp.getSource(), dim));
} else {
srcSizes.push_back(rewriter.getIndexAttr(sourceType.getDimSize(dim)));
}
}
// Strides of InsertSliceOp are all 1.
SmallVector<OpFoldResult> strides(sourceType.getRank(),
rewriter.getIndexAttr(1));
rewriter.replaceOpWithNewOp<tensor::InsertSliceOp>(
padOp, padOp.getSource(), fill, padOp.getMixedLowPad(), srcSizes,
strides);
return success();
}
LogicalResult ExtractSliceOfPadTensorSwapPattern::matchAndRewrite(
tensor::ExtractSliceOp sliceOp, PatternRewriter &rewriter) const {
if (!sliceOp.hasUnitStride())
return failure();
auto padOp = sliceOp.getSource().getDefiningOp<tensor::PadOp>();
if (!padOp)
return failure();
bool zeroSliceGuard = true;
if (controlFn) {
if (std::optional<bool> control = controlFn(sliceOp))
zeroSliceGuard = *control;
else
return failure();
}
Operation *tiledPadOp =
tensor::bubbleUpPadSlice(rewriter, padOp, sliceOp.getMixedOffsets(),
sliceOp.getMixedSizes(), zeroSliceGuard);
// All shapes are static and the data source is actually used. Rewrite into
// pad(extract_slice(x)).
rewriter.replaceOp(sliceOp, tiledPadOp->getResults());
return success();
}
/// Returns a tensor.pad op if padding value is set. Otherwise, returns the
/// source directly. The method assumes that the `packOp` has static shapes.
static Value getPackOpSourceOrPaddedSource(OpBuilder &builder,
tensor::PackOp packOp) {
Value input = packOp.getSource();
if (!packOp.getPaddingValue()) {
return input;
}
Location loc = packOp.getLoc();
ShapedType inputType = packOp.getSourceType();
int64_t inputRank = inputType.getRank();
assert(llvm::all_of(packOp.getDestType().getShape().take_front(inputRank),
[](int64_t val) { return val == 1; }));
SmallVector<int64_t> paddedShape;
DenseMap<int64_t, OpFoldResult> tileAndPosMapping =
packOp.getDimAndTileMapping();
for (int64_t dim = 0; dim < inputRank; ++dim) {
int64_t size = inputType.getDimSize(dim);
if (!tileAndPosMapping.count(dim)) {
paddedShape.push_back(size);
continue;
}
// The size is less than or equal to tileSize because outer dims are all 1s.
std::optional<int64_t> tileSize =
getConstantIntValue(tileAndPosMapping.lookup(dim));
assert(tileSize.has_value() && "dynamic inner tile size is not supported");
paddedShape.push_back(tileSize.value());
}
auto resultType =
RankedTensorType::get(paddedShape, inputType.getElementType());
return tensor::createPadHighOp(resultType, input, packOp.getPaddingValue(),
/*nofold=*/false, loc, builder);
}
static SmallVector<int64_t>
getPackUnpackNormalizedInnerPerm(int rank, ArrayRef<int64_t> innerDimsPos) {
constexpr int64_t kNonTiledMarker = -1;
SmallVector<int64_t> vec(rank, kNonTiledMarker);
for (auto [index, value] : llvm::enumerate(innerDimsPos))
vec[value] = index;
SmallVector<int64_t> perm = llvm::to_vector(llvm::make_filter_range(
vec, [&](int64_t v) { return v != kNonTiledMarker; }));
return perm;
}
LogicalResult GeneralizeOuterUnitDimsPackOpPattern::matchAndRewrite(
tensor::PackOp packOp, PatternRewriter &rewriter) const {
// TODO: support the case that outer dimensions are not all 1s A
// tensor.expand_shape will be generated in this case.
int64_t srcRank = packOp.getSourceRank();
if (llvm::any_of(packOp.getDestType().getShape().take_front(srcRank),
[](int64_t val) { return val != 1; })) {
return rewriter.notifyMatchFailure(
packOp, "require the outer dimension of the result are all 1s");
}
if (llvm::any_of(packOp.getMixedTiles(),
[](OpFoldResult tile) { return tile.is<Value>(); })) {
return rewriter.notifyMatchFailure(packOp,
"require inner tile sizes being static");
}
// 1. Use rank-reduced tensor.extract_slice op to extract the tile.
Location loc = packOp.getLoc();
Attribute zeroIdxAttr = rewriter.getIndexAttr(0);
Attribute oneIdxAttr = rewriter.getIndexAttr(1);
SmallVector<OpFoldResult> readOffsets(srcRank, zeroIdxAttr);
SmallVector<OpFoldResult> readStrides(srcRank, oneIdxAttr);
SmallVector<OpFoldResult> readSizes;
SmallVector<int64_t> readShape;
DenseMap<int64_t, OpFoldResult> dimAndTileMapping =
packOp.getDimAndTileMapping();
for (auto i : llvm::seq<unsigned>(0, srcRank)) {
if (!dimAndTileMapping.count(i)) {
readSizes.push_back(oneIdxAttr);
continue;
}
readSizes.push_back(dimAndTileMapping[i]);
readShape.push_back(getConstantIntValue(dimAndTileMapping[i])
.value_or(ShapedType::kDynamic));
}
Type elemType = packOp.getSourceType().getElementType();
auto readType = RankedTensorType::get(readShape, elemType);
Value input = getPackOpSourceOrPaddedSource(rewriter, packOp);
Value tile = rewriter.create<tensor::ExtractSliceOp>(
loc, readType, input, readOffsets, readSizes, readStrides);
// 2. Transpose the tile to match the inner tile order.
SmallVector<int64_t> perm =
getPackUnpackNormalizedInnerPerm(srcRank, packOp.getInnerDimsPos());
SmallVector<int64_t> transpShape = readShape;
applyPermutationToVector<int64_t>(transpShape, perm);
Value empty = rewriter.create<tensor::EmptyOp>(loc, transpShape, elemType);
auto transposedOp =
rewriter.create<linalg::TransposeOp>(loc, tile, empty, perm);
// 3. Insert the inner tile to the destination.
int64_t destRank = packOp.getDestRank();
SmallVector<OpFoldResult> writeStrides(destRank, oneIdxAttr);
SmallVector<OpFoldResult> writeOffsets(destRank, zeroIdxAttr);
SmallVector<OpFoldResult> writeSizes(srcRank, oneIdxAttr);
for (auto size : transpShape)
writeSizes.push_back(rewriter.getIndexAttr(size));
auto insert = rewriter.create<tensor::InsertSliceOp>(
loc, transposedOp.getResult()[0], packOp.getDest(), writeOffsets,
writeSizes, writeStrides);
rewriter.replaceOp(packOp, insert.getResult());
return success();
}
LogicalResult GeneralizeOuterUnitDimsUnPackOpPattern::matchAndRewrite(
tensor::UnPackOp unpackOp, PatternRewriter &rewriter) const {
int64_t srcRank = unpackOp.getSourceRank();
int64_t destRank = unpackOp.getDestRank();
ArrayRef<int64_t> srcShape = unpackOp.getSourceType().getShape();
if (llvm::any_of(srcShape.take_front(destRank),
[](int64_t val) { return val != 1; })) {
return rewriter.notifyMatchFailure(
unpackOp, "require the outer dimension of the result are all 1s");
}
// 1. Use rank-reduced tensor.extract_slice op to extract the tile.
Location loc = unpackOp.getLoc();
Attribute zeroIdxAttr = rewriter.getIndexAttr(0);
Attribute oneIdxAttr = rewriter.getIndexAttr(1);
SmallVector<OpFoldResult> readOffsets(srcRank, zeroIdxAttr);
SmallVector<OpFoldResult> readStrides(srcRank, oneIdxAttr);
auto mixedTiles = unpackOp.getMixedTiles();
SmallVector<OpFoldResult> readSizes(destRank, oneIdxAttr);
readSizes.append(mixedTiles.begin(), mixedTiles.end());
// Explicitly create the type for extract_slice op because the inner tile
// size could be 1. We want to represent the whole inner tile in this case.
ArrayRef<int64_t> readShape = srcShape.drop_front(destRank);
Type elemType = unpackOp.getSourceType().getElementType();
auto readType = RankedTensorType::get(readShape, elemType);
Value innerTile = rewriter.create<tensor::ExtractSliceOp>(
loc, readType, unpackOp.getSource(), readOffsets, readSizes, readStrides);
// 2. Transpose the tile to match the outer corresponding tile order.
ArrayRef<int64_t> innerDimsPos = unpackOp.getInnerDimsPos();
SmallVector<int64_t> perm =
getPackUnpackNormalizedInnerPerm(srcRank, innerDimsPos);
SmallVector<int64_t> transpShape(readShape);
applyPermutationToVector<int64_t>(transpShape, perm);
Value empty = rewriter.create<tensor::EmptyOp>(loc, transpShape, elemType);
auto transposedOp =
rewriter.create<linalg::TransposeOp>(loc, innerTile, empty, perm);
// 3. Handle in-complete tiles if needed. It truncates trailing data from the
// transposed tile.
int numLoops = transpShape.size();
SmallVector<OpFoldResult> tileStrides(numLoops, oneIdxAttr);
SmallVector<OpFoldResult> tileOffsets(numLoops, zeroIdxAttr);
SmallVector<OpFoldResult> tileSizes;
for (int dim : innerDimsPos)
tileSizes.push_back(getAsOpFoldResult(
rewriter.createOrFold<tensor::DimOp>(loc, unpackOp.getDest(), dim)));
applyPermutationToVector<OpFoldResult>(tileSizes, perm);
auto partialTile = rewriter.create<tensor::ExtractSliceOp>(
loc, transposedOp.getResult()[0], tileOffsets, tileSizes, tileStrides);
// 4. Insert the result to the destination tensor.
SmallVector<OpFoldResult> writeSizes;
SmallVector<OpFoldResult> writeStrides(destRank, oneIdxAttr);
SmallVector<OpFoldResult> writeOffsets(destRank, zeroIdxAttr);
DenseMap<int64_t, OpFoldResult> dimAndTileMapping =
unpackOp.getDimAndTileMapping();
for (int i = 0, idx = 0; i < destRank; ++i) {
if (dimAndTileMapping.count(i))
writeSizes.push_back(tileSizes[idx++]);
else
writeSizes.push_back(oneIdxAttr);
}
auto insert = rewriter.create<tensor::InsertSliceOp>(
loc, partialTile, unpackOp.getDest(), writeOffsets, writeSizes,
writeStrides);
rewriter.replaceOp(unpackOp, insert.getResult());
return success();
}
// The following are patterns for downscaling convolution ops with size-1
// window dimensions.
//
// Note that we'd eventually want to write such transformations in a generic
// way, e.g., converting to linalg.generic, removing the size-1 dimensions,
// and then turning back to named ops. But for now it's fine to have a few
// patterns matching special ops to get started.
template <typename Conv2DOp, typename Conv1DOp>
FailureOr<Conv1DOp> DownscaleSizeOneWindowed2DConvolution<Conv2DOp, Conv1DOp>::
returningMatchAndRewrite(Conv2DOp convOp, PatternRewriter &rewriter) const {
if (convOp.hasBufferSemantics())
return failure(); // To be implemented.
Value input = convOp.getInputs().front();
Value kernel = convOp.getInputs().back();
Value output = convOp.getOutputs().front();
auto inputType = input.getType().dyn_cast<RankedTensorType>();
auto kernelType = kernel.getType().dyn_cast<RankedTensorType>();
auto outputType = output.getType().dyn_cast<RankedTensorType>();
auto kernelShape = kernelType.getShape();
auto outputShape = outputType.getShape();
// Get domain indices based on conv2D layout.
auto [khIndex, kwIndex, ohIndex, owIndex] =
TypeSwitch<Operation *, std::tuple<int64_t, int64_t, int64_t, int64_t>>(
convOp)
.Case([&](linalg::Conv2DNhwcHwcfOp op) {
return std::make_tuple(0, 1, 1, 2);
})
.Case([&](linalg::Conv2DNchwFchwOp op) {
return std::make_tuple(2, 3, 2, 3);
})
.Case([&](linalg::PoolingNhwcSumOp op) {
return std::make_tuple(0, 1, 1, 2);
})
.Case([&](linalg::PoolingNchwSumOp op) {
return std::make_tuple(0, 1, 2, 3);
})
.Case([&](linalg::PoolingNhwcMaxOp op) {
return std::make_tuple(0, 1, 1, 2);
})
.Case([&](linalg::PoolingNhwcMaxUnsignedOp op) {
return std::make_tuple(0, 1, 1, 2);
})
.Case([&](linalg::PoolingNhwcMinOp op) {
return std::make_tuple(0, 1, 1, 2);
})
.Case([&](linalg::PoolingNhwcMinUnsignedOp op) {
return std::make_tuple(0, 1, 1, 2);
})
.Case([&](linalg::PoolingNchwMaxOp op) {
return std::make_tuple(0, 1, 2, 3);
})
.Default([&](Operation *op) {
llvm_unreachable("unexpected conv2d/pool2d operation.");
return std::make_tuple(0, 0, 0, 0);
});
// Only handle the case where at least one of the window dimensions is
// of size 1. Other cases can rely on tiling to reduce to such cases.
int64_t khSize = kernelShape[khIndex], kwSize = kernelShape[kwIndex];
int64_t ohSize = outputShape[ohIndex], owSize = outputShape[owIndex];
bool removeH = (khSize == 1 && ohSize == 1);
bool removeW = (kwSize == 1 && owSize == 1);
if (!removeH && !removeW)
return failure();
// Get new shapes and types for all operands by removing the size-1
// dimension.
using RTTBuilder = RankedTensorType::Builder;
RankedTensorType newInputType =
RTTBuilder(inputType).dropDim((removeH ? ohIndex : owIndex));
RankedTensorType newKernelType =
RTTBuilder(kernelType).dropDim((removeH ? khIndex : kwIndex));
RankedTensorType newOutputType =
RTTBuilder(outputType).dropDim((removeH ? ohIndex : owIndex));
// Rank-reduce operands.
Location loc = convOp.getLoc();
Value newInput = tensor::createCanonicalRankReducingExtractSliceOp(
rewriter, loc, input, newInputType);
Value newKernel = tensor::createCanonicalRankReducingExtractSliceOp(
rewriter, loc, kernel, newKernelType);
Value newOutput = tensor::createCanonicalRankReducingExtractSliceOp(
rewriter, loc, output, newOutputType);
// Rank-reduce strides and dilations too.
// TODO: dropDim 1-liner helper.
auto strides =
llvm::to_vector<4>(convOp.getStrides().template getValues<int64_t>());
strides.erase(strides.begin() + (removeH ? 0 : 1));
auto stridesAttr = rewriter.getI64VectorAttr(strides);
auto dilations =
llvm::to_vector<4>(convOp.getDilations().template getValues<int64_t>());
dilations.erase(dilations.begin() + (removeH ? 0 : 1));
auto dilationsAttr = rewriter.getI64VectorAttr(dilations);
auto conv1DOp = rewriter.create<Conv1DOp>(
loc, newOutputType, ValueRange{newInput, newKernel},
ValueRange{newOutput}, stridesAttr, dilationsAttr);
// Insert back.
Value inserted = tensor::createCanonicalRankReducingInsertSliceOp(
rewriter, loc, conv1DOp.getResult(0), output);
rewriter.replaceOp(convOp, inserted);
return conv1DOp;
}
template struct linalg::DownscaleSizeOneWindowed2DConvolution<Conv2DNhwcHwcfOp,
Conv1DNwcWcfOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<Conv2DNchwFchwOp,
Conv1DNcwFcwOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<PoolingNhwcSumOp,
PoolingNwcSumOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<PoolingNchwSumOp,
PoolingNcwSumOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<PoolingNhwcMaxOp,
PoolingNwcMaxOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<
PoolingNhwcMaxUnsignedOp, PoolingNwcMaxUnsignedOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<PoolingNhwcMinOp,
PoolingNwcMinOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<
PoolingNhwcMinUnsignedOp, PoolingNwcMinUnsignedOp>;
template struct linalg::DownscaleSizeOneWindowed2DConvolution<PoolingNchwMaxOp,
PoolingNcwMaxOp>;
FailureOr<DepthwiseConv1DNwcWcOp>
DownscaleDepthwiseConv2DNhwcHwcOp::returningMatchAndRewrite(
DepthwiseConv2DNhwcHwcOp convOp, PatternRewriter &rewriter) const {
if (convOp.hasBufferSemantics())
return failure(); // To be implemented.
Value input = convOp.getInputs().front();
Value kernel = convOp.getInputs().back();
Value output = convOp.getOutputs().front();
auto inputType = input.getType().dyn_cast<RankedTensorType>();
auto kernelType = kernel.getType().dyn_cast<RankedTensorType>();
auto outputType = output.getType().dyn_cast<RankedTensorType>();
auto kernelShape = kernelType.getShape();
auto outputShape = outputType.getShape();
// Only handle the case where at least one of the window dimensions is
// of size 1. Other cases can rely on tiling to reduce to such cases.
int64_t khSize = kernelShape[0], kwSize = kernelShape[1];
int64_t ohSize = outputShape[1], owSize = outputShape[2];
bool removeH = (khSize == 1 && ohSize == 1);
bool removeW = (kwSize == 1 && owSize == 1);
if (!removeH && !removeW)
return failure();
// Get new shapes and types for all operands by removing the size-1
// dimension.
using RTTBuilder = RankedTensorType::Builder;
RankedTensorType newInputType =
RTTBuilder(inputType).dropDim((removeH ? 1 : 2));
RankedTensorType newKernelType =
RTTBuilder(kernelType).dropDim((removeH ? 0 : 1));
RankedTensorType newOutputType =
RTTBuilder(outputType).dropDim(removeH ? 1 : 2);
// Rank-reduce operands.
Location loc = convOp.getLoc();
Value newInput = tensor::createCanonicalRankReducingExtractSliceOp(
rewriter, loc, input, newInputType);
Value newKernel = tensor::createCanonicalRankReducingExtractSliceOp(
rewriter, loc, kernel, newKernelType);
Value newOutput = tensor::createCanonicalRankReducingExtractSliceOp(
rewriter, loc, output, newOutputType);
// Rank-reduce strides and dilations too.
// TODO: dropDim 1-liner helper.
auto strides = llvm::to_vector<4>(convOp.getStrides().getValues<int64_t>());
strides.erase(strides.begin() + (removeH ? 0 : 1));
auto stridesAttr = rewriter.getI64VectorAttr(strides);
auto dilations =
llvm::to_vector<4>(convOp.getDilations().getValues<int64_t>());
dilations.erase(dilations.begin() + (removeH ? 0 : 1));
auto dilationsAttr = rewriter.getI64VectorAttr(dilations);
auto conv1DOp = rewriter.create<DepthwiseConv1DNwcWcOp>(
loc, newOutputType, ValueRange{newInput, newKernel},
ValueRange{newOutput}, stridesAttr, dilationsAttr);
// Insert back.
Value inserted = tensor::createCanonicalRankReducingInsertSliceOp(
rewriter, loc, conv1DOp.getResult(0), output);
rewriter.replaceOp(convOp, inserted);
return conv1DOp;
}
void linalg::populateDecomposeConvolutionPatterns(RewritePatternSet &patterns,
PatternBenefit benefit) {
patterns.add<DownscaleSizeOneWindowed2DConvolution<linalg::Conv2DNhwcHwcfOp,
Conv1DNwcWcfOp>,
DownscaleSizeOneWindowed2DConvolution<linalg::Conv2DNchwFchwOp,
Conv1DNcwFcwOp>,
DownscaleDepthwiseConv2DNhwcHwcOp>(patterns.getContext(),
benefit);
patterns.add<
DownscaleSizeOneWindowed2DConvolution<PoolingNhwcSumOp, PoolingNwcSumOp>,
DownscaleSizeOneWindowed2DConvolution<PoolingNchwSumOp, PoolingNcwSumOp>,
DownscaleSizeOneWindowed2DConvolution<PoolingNhwcMaxOp, PoolingNwcMaxOp>,
DownscaleSizeOneWindowed2DConvolution<PoolingNhwcMaxUnsignedOp,
PoolingNwcMaxUnsignedOp>,
DownscaleSizeOneWindowed2DConvolution<PoolingNhwcMinOp, PoolingNwcMinOp>,
DownscaleSizeOneWindowed2DConvolution<PoolingNhwcMinUnsignedOp,
PoolingNwcMinUnsignedOp>,
DownscaleSizeOneWindowed2DConvolution<PoolingNchwMaxOp, PoolingNcwMaxOp>>(
patterns.getContext(), benefit);
}
//===----------------------------------------------------------------------===//
// pack transformation.
//===----------------------------------------------------------------------===//
#ifndef NDEBUG
/// Return true if `map` has 0 or 1 result function of AffineDimExpr(dim).
static bool hasAtMostOneResultFunctionOfDim(AffineMap map, int64_t dim) {
bool found = false;
for (AffineExpr e : map.getResults()) {
if (!e.isFunctionOfDim(dim))
continue;
if (found)
return false;
found = true;
}
return true;
}
#endif // NDEBUG
/// Return the index of the first result of `map` that is a function of
/// AffineDimExpr(dim), std::nullopt otherwise.
static std::optional<int64_t> getFirstResultIndexFunctionOf(AffineMap map,
int64_t dim) {
for (int64_t i = 0, e = map.getNumResults(); i < e; ++i) {
AffineExpr expr = map.getResult(i);
if (!expr.isFunctionOfDim(dim))
continue;
return i;
}
return std::nullopt;
}
/// Perform one step of packing of a LinalgOp's metadata along `dim` into the
/// `newDim` at `iteratorTypes.size()` by:
/// 1. Appending `iteratorTypes[newDim]`, equal to `iteratorTypes[dim]`.
/// 2. Appending a `newDim` to the domain of every indexing map.
/// 3. For each operand (i.e. for each map in `indexingMaps`), perform packing
/// by potentially adding a `newDim` result to `map`.
/// The preserved invariant is that `iteratorTypes.size()` is always equal to
/// `map.getNumDims()` for every map in `indexingMaps`.
///
/// Update `indexingMaps` and `iteratorTypes` inplace as one step of the update.
/// Return a vector that records the optional packing for each operand.
/// Return failure if the packed indexing cannot be represented with a LinalgOp.
///
/// Further details:
/// ================
/// The current implementation of packing (i.e. data tiling) consists of
/// rewriting a linearized strip-mined form into a higher-dimensional access.
/// e.g. consider an access `A[I][f(j, k, l)]` and packing by 4; we rewrite
/// `I` into `4 * i + ii`, where `0 <= ii < 4`.
/// The access is further rewritten as `A[i][f(j, k, l)][ii]`.
///
/// This rewrite into higher dimensional access is not possible for general
/// AffineExpr in Linalg atm, it is restricted to an AffineDimExpr:
/// e.g. consider an access `A[I + J][f(j, k, l)]` and packing by 4; we
/// rewrite `I + J` into `4 * i + ii + J`, where `0 <= ii < 4`.
/// The rewrite of the access would be a form not representable in Linalg:
/// `A[i + (ii + J) / 4][f(j, k, l)][(ii + J) % 4]`.
/// Note however that as `J` and `ii` iterate, the accesses do not have a
/// particular alignment, so packing does not achieve alignment in this case
///
/// In the future, we may want to consider a mixed-form that allows some
/// alignment in the presence of multiple accesses:
/// `A[I][f(j, k, l)]` and `B[I + J][f(j, k, l)]`
/// And would rewrite accesses as:
/// `A[i][f(j, k, l)][ii]` and `B[4 * i + ii + J][f(j, k, l)]`
static FailureOr<SmallVector<std::optional<int64_t>>>
packLinalgMetadataOnce(SmallVectorImpl<AffineMap> &indexingMaps,
SmallVectorImpl<utils::IteratorType> &iteratorTypes,
int64_t dim) {
int64_t newDim = iteratorTypes.size();
iteratorTypes.push_back(iteratorTypes[dim]);
SmallVector<std::optional<int64_t>> packedDimPerIndexingMap(
indexingMaps.size(), std::nullopt);
SmallVector<AffineMap> newMaps;
for (int64_t operandIdx = 0, e = indexingMaps.size(); operandIdx < e;
++operandIdx) {
AffineMap map = indexingMaps[operandIdx];
// Add the `newDim` to map whatever the case.
assert(map.getNumDims() == newDim && "num dims invariant violation");
map = map.shiftDims(1, newDim);
// Get the at-most-1 index of the result that is a function of `dim`.
// If we can find one, we insert `AffineDimExpr(newDim)` to the map, which
// logically chunks dimension `dim` into `K * dim + newDim`, where the
// packing factor `K` is specified separately.
assert(hasAtMostOneResultFunctionOfDim(map, dim) &&
"num results invariant violation");
auto maybeOperandDimensionToPack = getFirstResultIndexFunctionOf(map, dim);
if (!maybeOperandDimensionToPack.has_value()) {
newMaps.push_back(map);
continue;
}
// We can only pack AffineDimExpr atm.
if (!map.getResult(maybeOperandDimensionToPack.value())
.isa<AffineDimExpr>())
return failure();
// Add `newDim` to the results of the map.
map = map.insertResult(Builder(map.getContext()).getAffineDimExpr(newDim),
map.getNumResults());
newMaps.push_back(map);
// Record the that `operandIdx` is packed.
packedDimPerIndexingMap[operandIdx] = maybeOperandDimensionToPack;
}
indexingMaps = newMaps;
return packedDimPerIndexingMap;
}
namespace {
/// Helper struct to encode packing along one dimension of a LinalgOp.
struct PackedOperandsDim {
OpFoldResult packedSize;
SmallVector<std::optional<int64_t>> packedDimForEachOperand;
};
/// Helper struct to encode packing along all dimensions of a LinalgOp.
struct PackedOperandsDimList {
void push_back(PackedOperandsDim &&packedOperandsDims) {
spec.emplace_back(packedOperandsDims);
}
/// Return all the dims that have been packed for operand @ `operandPos`.
SmallVector<int64_t> extractPackedDimsForOperand(int64_t operandPos);
/// Return all the pack sizes by which an operand @ `operandPos` is packed.
SmallVector<OpFoldResult> extractPackSizesForOperand(int64_t operandPos);
private:
SmallVector<PackedOperandsDim> spec;
};
} // namespace
SmallVector<int64_t>
PackedOperandsDimList::extractPackedDimsForOperand(int64_t operandPos) {
SmallVector<int64_t> res;
for (int64_t i = 0, e = spec.size(); i < e; ++i) {
if (!spec[i].packedDimForEachOperand[operandPos].has_value())
continue;
res.push_back(spec[i].packedDimForEachOperand[operandPos].value());
}
return res;
}
SmallVector<OpFoldResult>
PackedOperandsDimList::extractPackSizesForOperand(int64_t operandPos) {
SmallVector<OpFoldResult> res;
for (int64_t i = 0, e = spec.size(); i < e; ++i) {
if (!spec[i].packedDimForEachOperand[operandPos].has_value())
continue;
res.push_back(spec[i].packedSize);
}
return res;
}
/// Implement packing of a single LinalgOp by performing packing by
/// `packedSizes`. There must be one packedSizes entry per `linalgOp` iterator.
/// Return the packed Linalg op on success, failure otherwise.
FailureOr<PackResult> linalg::pack(RewriterBase &rewriter,
linalg::LinalgOp linalgOp,
ArrayRef<OpFoldResult> packedSizes) {
if (packedSizes.size() != linalgOp.getNumLoops()) {
return rewriter.notifyMatchFailure(linalgOp,
"incorrect number of pack sizes");
}
Location loc = linalgOp->getLoc();
SmallVector<AffineMap> indexingMaps = linalgOp.getIndexingMapsArray();
SmallVector<utils::IteratorType> iteratorTypes =
linalgOp.getIteratorTypesArray();
LLVM_DEBUG(DBGS() << "Start packing: " << linalgOp << "\n";
llvm::interleaveComma(indexingMaps, DBGS() << "maps: "); DBGSNL();
llvm::interleaveComma(iteratorTypes, DBGS() << "iterators: ");
DBGSNL(););
SmallVector<tensor::PackOp> packOps;
SmallVector<tensor::UnPackOp> unPackOps;
// Step 1. Pack each dim of the LinalgOp metadata by packedSizes[i].
PackedOperandsDimList listOfPackedOperandsDim;
for (int64_t i = 0, e = packedSizes.size(); i < e; ++i) {
std::optional<int64_t> maybeConstant = getConstantIntValue(packedSizes[i]);
// Skip tile sizes explicitly set to 0.
if (maybeConstant.has_value() && maybeConstant.value() == 0)
continue;
PackedOperandsDim packedOperandsDims;
packedOperandsDims.packedSize = packedSizes[i];
FailureOr<SmallVector<std::optional<int64_t>>>
maybePackedDimForEachOperand =
packLinalgMetadataOnce(indexingMaps, iteratorTypes, i);
if (failed(maybePackedDimForEachOperand))
return failure();
packedOperandsDims.packedDimForEachOperand = *maybePackedDimForEachOperand;
listOfPackedOperandsDim.push_back(std::move(packedOperandsDims));
LLVM_DEBUG(
DBGS() << "++++ After pack size #" << i << ": " << packedSizes[i]
<< "\n";
llvm::interleaveComma(indexingMaps, DBGS() << "maps: "); DBGSNL();
llvm::interleaveComma(iteratorTypes, DBGS() << "iterators: "); DBGSNL();
llvm::interleaveComma(packedOperandsDims.packedDimForEachOperand,
DBGS() << "packedDimForEachOperand: ");
DBGSNL(););
}
// Step 2. Propagate packing to all LinalgOp operands.
SmallVector<Value> inputsAndInits, results;
for (auto operandsList :
{linalgOp.getDpsInputOperands(), linalgOp.getDpsInitOperands()}) {
for (OpOperand *opOperandPtr : operandsList) {
int64_t pos = opOperandPtr->getOperandNumber();
Value operand = opOperandPtr->get();
SmallVector<int64_t> innerPos =
listOfPackedOperandsDim.extractPackedDimsForOperand(pos);
SmallVector<OpFoldResult> innerPackSizes =
listOfPackedOperandsDim.extractPackSizesForOperand(pos);
LLVM_DEBUG(
DBGS() << "operand: " << operand << "\n";
llvm::interleaveComma(innerPos, DBGS() << "innerPos: "); DBGSNL();
llvm::interleaveComma(innerPackSizes, DBGS() << "innerPackSizes: ");
DBGSNL(););
if (innerPackSizes.empty()) {
inputsAndInits.push_back(operand);
continue;
}
Value dest = tensor::PackOp::createDestinationTensor(
rewriter, loc, operand, innerPackSizes, innerPos,
/*outerDimsPerm=*/{});
// TODO: value of the padding attribute should be determined by consumers.
Attribute zeroAttr =
rewriter.getZeroAttr(getElementTypeOrSelf(dest.getType()));
Value zero = rewriter.create<arith::ConstantOp>(loc, zeroAttr);
packOps.push_back(rewriter.create<tensor::PackOp>(
loc, operand, dest, innerPos, innerPackSizes, zero));
inputsAndInits.push_back(packOps.back());
}
}
// Step 3. Build the packed op, use the type of `inits` as result types.
ValueRange inputs =
ValueRange{inputsAndInits}.take_front(linalgOp.getNumDpsInputs());
ValueRange inits =
ValueRange{inputsAndInits}.take_back(linalgOp.getNumDpsInits());
auto packedLinalgOp = rewriter.create<linalg::GenericOp>(
linalgOp.getLoc(), inits.getTypes(), inputs, inits, indexingMaps,
iteratorTypes);
packedLinalgOp.getRegion().takeBody(linalgOp->getRegion(0));
// Step 4. Propagate packing to all the op results.
for (OpResult result : packedLinalgOp->getResults()) {
int64_t resultNum = result.getResultNumber();
tensor::PackOp maybePackedInit =
inits[resultNum].getDefiningOp<tensor::PackOp>();
if (!maybePackedInit) {
results.push_back(result);
continue;
}
// Build the symmetrical UnPackOp to the existing PackOp.
unPackOps.push_back(rewriter.create<tensor::UnPackOp>(
packedLinalgOp->getLoc(), result, maybePackedInit.getSource(),
maybePackedInit.getInnerDimsPos(), maybePackedInit.getMixedTiles()));
results.push_back(unPackOps.back());
}
// Step 5. Replace `linalgOp`.
rewriter.replaceOp(linalgOp, results);
// Return packedLinalgOp.
return PackResult{packOps,
cast<linalg::LinalgOp>(packedLinalgOp.getOperation()),
unPackOps};
}
//===----------------------------------------------------------------------===//
// packTranspose transformation.
//===----------------------------------------------------------------------===//
/// Return a copy of `tensorType` after permutation by `permutationVector`.
// Note: Should be a new method in of MemRef/RankedTensor/VectorType::Builder
// but this would introduce a dependence on Dialect in IR.
// TODO: Restructure.
static RankedTensorType permuteShape(RankedTensorType tensorType,
ArrayRef<int64_t> permutationVector) {
SmallVector<int64_t> shape(tensorType.getShape());
applyPermutationToVector(shape, permutationVector);
return RankedTensorType::Builder(tensorType).setShape(shape);
}
/// Return a new GenericOp obtained by transposing opOperand by the permutation
/// vector:
/// - the corresponding indexing map is transposed by `permutation`
/// - the corresponding operand value is replaced by `transposedValue`
/// `linalgOp` is replaced by the return op in the process.
/// Asserts that `transposedValue` is of the proper transposed ShapedType.
static LinalgOp transposeOneLinalgOperandAndReplace(
RewriterBase &rewriter, LinalgOp linalgOp, OpOperand &opOperand,
ArrayRef<int64_t> permutation, Value transposedValue) {
// Sanity check the operand.
assert(linalgOp == opOperand.getOwner() && "linalg op must own the operand");
// Sanity check of the expected transposed tensor type.
auto tensorType = permuteShape(
opOperand.get().getType().cast<RankedTensorType>(), permutation);
(void)tensorType;
assert(tensorType == transposedValue.getType() &&
"expected tensor type mismatch");
// Compute the transposed indexing map.
// Sigh unsigned pollution.
SmallVector<unsigned> tmpTransposition = llvm::to_vector(
llvm::map_range(permutation, [](int64_t i) -> unsigned { return i; }));
AffineMap permutationMap =
AffineMap::getPermutationMap(tmpTransposition, rewriter.getContext());
AffineMap transposedMap =
permutationMap.compose(linalgOp.getMatchingIndexingMap(&opOperand));
// Set the transposed indexing map in the proper position.
SmallVector<AffineMap> indexingMaps = linalgOp.getIndexingMapsArray();
indexingMaps[linalgOp.getIndexingMapIndex(&opOperand)] = transposedMap;
// Set the transposedValue in the proper operand position.
SmallVector<Value> operands = linalgOp->getOperands();
operands[opOperand.getOperandNumber()] = transposedValue;
ValueRange operandsRef(operands);
auto transposedGenericOp = rewriter.create<linalg::GenericOp>(
/*location=*/linalgOp->getLoc(),
/*resultTensorTypes=*/
operandsRef.drop_front(linalgOp.getNumDpsInputs()).getTypes(),
/*inputs=*/operandsRef.take_front(linalgOp.getNumDpsInputs()),
/*outputs=*/operandsRef.drop_front(linalgOp.getNumDpsInputs()),
/*indexingMaps=*/indexingMaps,
/*iteratorTypes=*/linalgOp.getIteratorTypesArray());
transposedGenericOp.getRegion().takeBody(linalgOp->getRegion(0));
rewriter.replaceOp(linalgOp, transposedGenericOp->getResults());
return cast<linalg::LinalgOp>(transposedGenericOp.getOperation());
}
FailureOr<PackTransposeResult>
linalg::packTranspose(RewriterBase &rewriter, tensor::PackOp packOp,
linalg::LinalgOp linalgOp, tensor::UnPackOp maybeUnPackOp,
ArrayRef<int64_t> outerPerm,
ArrayRef<int64_t> innerPerm) {
Location loc = linalgOp.getLoc();
// Step 1. Transpose packOp.
rewriter.setInsertionPoint(packOp);
tensor::PackOp transposedPackOp =
packOp.createTransposedClone(rewriter, loc, innerPerm, outerPerm);
if (!packOp.getResult().hasOneUse())
return rewriter.notifyMatchFailure(linalgOp, "expect single pack use");
OpOperand &packUse = *packOp->getUses().begin();
if (packUse.getOwner() != linalgOp) {
return rewriter.notifyMatchFailure(
linalgOp, "not a single use by the LinalgOp target");
}
if (maybeUnPackOp &&
(!linalgOp.isDpsInit(&packUse) ||
maybeUnPackOp.getSource() != linalgOp.getTiedOpResult(&packUse))) {
return rewriter.notifyMatchFailure(linalgOp,
"not produced by the LinalgOp target");
}
// Step 2. Transpose linalgOp.
// transposedPackOp.getOuterDimsPerm() may be empty, in which case it is the
// identity. Don't rely on it.
int64_t numLeadingDims = packOp.getSourceRank();
int64_t numTrailingDims = packOp.getInnerDimsPos().size();
// Step 2.a. Compute the permutation on the whole operand.
// Leading part just reuse the outerPerm.
SmallVector<int64_t> permutation(outerPerm);
if (permutation.empty())
llvm::append_range(permutation, llvm::seq<int64_t>(0, numLeadingDims));
// Trailing part needs to reindex positions by `numLeadingDims`.
if (innerPerm.empty()) {
llvm::append_range(
permutation,
llvm::seq<int64_t>(numLeadingDims, numLeadingDims + numTrailingDims));
} else {
llvm::append_range(permutation,
llvm::map_range(innerPerm, [&](int64_t pos) {
return numLeadingDims + pos;
}));
}
if (!isPermutationVector(permutation))
return rewriter.notifyMatchFailure(linalgOp, "invalid permutation");
// Step 2.b. Save the transposedPackUse operand number in case we need to
// get the tied OpResult after `linalgOp` has been replaced.
int64_t packUseOperandNumber = packUse.getOperandNumber();
// Step 2.c. Actually perform the transposition.
rewriter.setInsertionPoint(linalgOp);
linalg::LinalgOp transposedLinalgOp = transposeOneLinalgOperandAndReplace(
rewriter, linalgOp, packUse, permutation, transposedPackOp.getResult());
// Step 3. Maybe transpose unPackOp.
tensor::UnPackOp transposedUnPackOp;
if (maybeUnPackOp) {
OpOperand &opOperand =
transposedLinalgOp->getOpOperand(packUseOperandNumber);
OpResult transposedResult = transposedLinalgOp.getTiedOpResult(&opOperand);
rewriter.setInsertionPoint(maybeUnPackOp);
transposedUnPackOp = maybeUnPackOp.createTransposedClone(
rewriter, loc, transposedResult, innerPerm, outerPerm);
rewriter.replaceOp(maybeUnPackOp, transposedUnPackOp->getResults());
}
// Step 4. Finally, replace packOp now that we don't need it anymore.
rewriter.replaceOp(packOp, transposedPackOp->getResults());
return PackTransposeResult{transposedPackOp, transposedLinalgOp,
transposedUnPackOp};
}