Files
llvm/mlir/lib/Dialect/Vector/Transforms/VectorLinearize.cpp
Christian Sigg fac349a169 Reapply "[mlir] Mark isa/dyn_cast/cast/... member functions depreca… (#90406)
…ted. (#89998)" (#90250)

This partially reverts commit 7aedd7dc75.

This change removes calls to the deprecated member functions. It does
not mark the functions deprecated yet and does not disable the
deprecation warning in TypeSwitch. This seems to cause problems with
MSVC.
2024-04-28 22:01:42 +02:00

416 lines
17 KiB
C++

//===- VectorLinearize.cpp - vector linearization transforms --------------===//
//
// 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 patterns and pass for linearizing ND vectors into 1D.
//
//===----------------------------------------------------------------------===//
#include "mlir/Dialect/Arith/IR/Arith.h"
#include "mlir/Dialect/Vector/IR/VectorOps.h"
#include "mlir/Dialect/Vector/Transforms/VectorRewritePatterns.h"
#include "mlir/IR/Attributes.h"
#include "mlir/IR/BuiltinAttributes.h"
#include "mlir/IR/Operation.h"
#include "mlir/IR/PatternMatch.h"
#include "mlir/IR/TypeUtilities.h"
#include "mlir/Support/LogicalResult.h"
#include "mlir/Transforms/DialectConversion.h"
#include "llvm/ADT/ArrayRef.h"
#include <cstdint>
#include <numeric>
using namespace mlir;
static bool isLessThanTargetBitWidth(Operation *op, unsigned targetBitWidth) {
auto resultTypes = op->getResultTypes();
for (auto resType : resultTypes) {
VectorType vecType = dyn_cast<VectorType>(resType);
// Reject index since getElementTypeBitWidth will abort for Index types.
if (!vecType || vecType.getElementType().isIndex())
return false;
// There are no dimension to fold if it is a 0-D vector.
if (vecType.getRank() == 0)
return false;
unsigned trailingVecDimBitWidth =
vecType.getShape().back() * vecType.getElementTypeBitWidth();
if (trailingVecDimBitWidth >= targetBitWidth)
return false;
}
return true;
}
namespace {
struct LinearizeConstant final : OpConversionPattern<arith::ConstantOp> {
using OpConversionPattern::OpConversionPattern;
LinearizeConstant(
const TypeConverter &typeConverter, MLIRContext *context,
unsigned targetVectBitWidth = std::numeric_limits<unsigned>::max(),
PatternBenefit benefit = 1)
: OpConversionPattern(typeConverter, context, benefit),
targetVectorBitWidth(targetVectBitWidth) {}
LogicalResult
matchAndRewrite(arith::ConstantOp constOp, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Location loc = constOp.getLoc();
auto resType =
getTypeConverter()->convertType<VectorType>(constOp.getType());
if (resType.isScalable() && !isa<SplatElementsAttr>(constOp.getValue()))
return rewriter.notifyMatchFailure(
loc,
"Cannot linearize a constant scalable vector that's not a splat");
if (!resType)
return rewriter.notifyMatchFailure(loc, "can't convert return type");
if (!isLessThanTargetBitWidth(constOp, targetVectorBitWidth))
return rewriter.notifyMatchFailure(
loc, "Can't flatten since targetBitWidth <= OpSize");
auto dstElementsAttr = dyn_cast<DenseElementsAttr>(constOp.getValue());
if (!dstElementsAttr)
return rewriter.notifyMatchFailure(loc, "unsupported attr type");
dstElementsAttr = dstElementsAttr.reshape(resType);
rewriter.replaceOpWithNewOp<arith::ConstantOp>(constOp, resType,
dstElementsAttr);
return success();
}
private:
unsigned targetVectorBitWidth;
};
struct LinearizeVectorizable final
: OpTraitConversionPattern<OpTrait::Vectorizable> {
using OpTraitConversionPattern::OpTraitConversionPattern;
public:
LinearizeVectorizable(
const TypeConverter &typeConverter, MLIRContext *context,
unsigned targetVectBitWidth = std::numeric_limits<unsigned>::max(),
PatternBenefit benefit = 1)
: OpTraitConversionPattern(typeConverter, context, benefit),
targetVectorBitWidth(targetVectBitWidth) {}
LogicalResult
matchAndRewrite(Operation *op, ArrayRef<Value> operands,
ConversionPatternRewriter &rewriter) const override {
if (!isLessThanTargetBitWidth(op, targetVectorBitWidth))
return rewriter.notifyMatchFailure(
op->getLoc(), "Can't flatten since targetBitWidth <= OpSize");
FailureOr<Operation *> newOp =
convertOpResultTypes(op, operands, *getTypeConverter(), rewriter);
if (failed(newOp))
return failure();
rewriter.replaceOp(op, (*newOp)->getResults());
return success();
}
private:
unsigned targetVectorBitWidth;
};
/// This pattern converts the ExtractStridedSliceOp into a ShuffleOp that works
/// on a linearized vector.
/// Following,
/// vector.extract_strided_slice %source
/// { offsets = [..], strides = [..], sizes = [..] }
/// is converted to :
/// %source_1d = vector.shape_cast %source
/// %out_1d = vector.shuffle %source_1d, %source_1d [ shuffle_indices_1d ]
/// %out_nd = vector.shape_cast %out_1d
/// `shuffle_indices_1d` is computed using the offsets and sizes of the
/// extraction.
struct LinearizeVectorExtractStridedSlice final
: public mlir::OpConversionPattern<mlir::vector::ExtractStridedSliceOp> {
using OpConversionPattern::OpConversionPattern;
LinearizeVectorExtractStridedSlice(
const TypeConverter &typeConverter, MLIRContext *context,
unsigned targetVectBitWidth = std::numeric_limits<unsigned>::max(),
PatternBenefit benefit = 1)
: OpConversionPattern(typeConverter, context, benefit),
targetVectorBitWidth(targetVectBitWidth) {}
LogicalResult
matchAndRewrite(vector::ExtractStridedSliceOp extractOp, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Type dstType = getTypeConverter()->convertType(extractOp.getType());
assert(!(extractOp.getVector().getType().isScalable() ||
cast<VectorType>(dstType).isScalable()) &&
"scalable vectors are not supported.");
if (!isLessThanTargetBitWidth(extractOp, targetVectorBitWidth))
return rewriter.notifyMatchFailure(
extractOp, "Can't flatten since targetBitWidth <= OpSize");
ArrayAttr offsets = extractOp.getOffsets();
ArrayAttr sizes = extractOp.getSizes();
ArrayAttr strides = extractOp.getStrides();
if (!isConstantIntValue(strides[0], 1))
return rewriter.notifyMatchFailure(
extractOp, "Strided slice with stride != 1 is not supported.");
Value srcVector = adaptor.getVector();
// If kD offsets are specified for nD source vector (n > k), the granularity
// of the extraction is greater than 1. In this case last (n-k) dimensions
// form the extraction granularity.
// Example :
// vector.extract_strided_slice %src {
// offsets = [0, 0], sizes = [2, 2], strides = [1, 1]} :
// vector<4x8x8xf32> to vector<2x2x8xf32>
// Here, extraction granularity is 8.
int64_t extractGranularitySize = 1;
int64_t nD = extractOp.getSourceVectorType().getRank();
int64_t kD = (int64_t)offsets.size();
int64_t k = kD;
while (k < nD) {
extractGranularitySize *= extractOp.getSourceVectorType().getShape()[k];
++k;
}
// Get total number of extracted slices.
int64_t nExtractedSlices = 1;
for (Attribute size : sizes) {
nExtractedSlices *= cast<IntegerAttr>(size).getInt();
}
// Compute the strides of the source vector considering first k dimensions.
llvm::SmallVector<int64_t, 4> sourceStrides(kD, extractGranularitySize);
for (int i = kD - 2; i >= 0; --i) {
sourceStrides[i] = sourceStrides[i + 1] *
extractOp.getSourceVectorType().getShape()[i + 1];
}
// Final shuffle indices has nExtractedSlices * extractGranularitySize
// elements.
llvm::SmallVector<int64_t, 4> indices(nExtractedSlices *
extractGranularitySize);
// Compute the strides of the extracted kD vector.
llvm::SmallVector<int64_t, 4> extractedStrides(kD, 1);
// Compute extractedStrides.
for (int i = kD - 2; i >= 0; --i) {
extractedStrides[i] =
extractedStrides[i + 1] * cast<IntegerAttr>(sizes[i + 1]).getInt();
}
// Iterate over all extracted slices from 0 to nExtractedSlices - 1
// and compute the multi-dimensional index and the corresponding linearized
// index within the source vector.
for (int64_t i = 0; i < nExtractedSlices; ++i) {
int64_t index = i;
// Compute the corresponding multi-dimensional index.
llvm::SmallVector<int64_t, 4> multiDimIndex(kD, 0);
for (int64_t j = 0; j < kD; ++j) {
multiDimIndex[j] = (index / extractedStrides[j]);
index -= multiDimIndex[j] * extractedStrides[j];
}
// Compute the corresponding linearized index in the source vector
// i.e. shift the multiDimIndex by the offsets.
int64_t linearizedIndex = 0;
for (int64_t j = 0; j < kD; ++j) {
linearizedIndex +=
(cast<IntegerAttr>(offsets[j]).getInt() + multiDimIndex[j]) *
sourceStrides[j];
}
// Fill the indices array form linearizedIndex to linearizedIndex +
// extractGranularitySize.
for (int64_t j = 0; j < extractGranularitySize; ++j) {
indices[i * extractGranularitySize + j] = linearizedIndex + j;
}
}
// Perform a shuffle to extract the kD vector.
rewriter.replaceOpWithNewOp<vector::ShuffleOp>(
extractOp, dstType, srcVector, srcVector,
rewriter.getI64ArrayAttr(indices));
return success();
}
private:
unsigned targetVectorBitWidth;
};
/// This pattern converts the ShuffleOp that works on nD (n > 1)
/// vectors to a ShuffleOp that works on linearized vectors.
/// Following,
/// vector.shuffle %v1, %v2 [ shuffle_indices ]
/// is converted to :
/// %v1_1d = vector.shape_cast %v1
/// %v2_1d = vector.shape_cast %v2
/// %out_1d = vector.shuffle %v1_1d, %v2_1d [ shuffle_indices_1d ]
/// %out_nd = vector.shape_cast %out_1d
// `shuffle_indices_1d` is computed using the sizes and `shuffle_indices`
/// of the original shuffle operation.
struct LinearizeVectorShuffle final
: public OpConversionPattern<vector::ShuffleOp> {
using OpConversionPattern::OpConversionPattern;
LinearizeVectorShuffle(
const TypeConverter &typeConverter, MLIRContext *context,
unsigned targetVectBitWidth = std::numeric_limits<unsigned>::max(),
PatternBenefit benefit = 1)
: OpConversionPattern(typeConverter, context, benefit),
targetVectorBitWidth(targetVectBitWidth) {}
LogicalResult
matchAndRewrite(vector::ShuffleOp shuffleOp, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Type dstType = getTypeConverter()->convertType(shuffleOp.getType());
assert(!(shuffleOp.getV1VectorType().isScalable() ||
shuffleOp.getV2VectorType().isScalable() ||
cast<VectorType>(dstType).isScalable()) &&
"scalable vectors are not supported.");
if (!isLessThanTargetBitWidth(shuffleOp, targetVectorBitWidth))
return rewriter.notifyMatchFailure(
shuffleOp, "Can't flatten since targetBitWidth <= OpSize");
Value vec1 = adaptor.getV1();
Value vec2 = adaptor.getV2();
int shuffleSliceLen = 1;
int rank = shuffleOp.getV1().getType().getRank();
// If rank > 1, we need to do the shuffle in the granularity of slices
// instead of scalars. Size of the slice is equal to the rank-1 innermost
// dims. Mask of the shuffle op specifies which slice to take from the
// outermost dim.
if (rank > 1) {
llvm::ArrayRef<int64_t> shape = shuffleOp.getV1().getType().getShape();
for (unsigned i = 1; i < shape.size(); ++i) {
shuffleSliceLen *= shape[i];
}
}
// For each value in the mask, we generate the indices of the source vectors
// that needs to be shuffled to the destination vector. If shuffleSliceLen >
// 1 we need to shuffle the slices (consecutive shuffleSliceLen number of
// elements) instead of scalars.
ArrayAttr mask = shuffleOp.getMask();
int64_t totalSizeOfShuffledElmnts = mask.size() * shuffleSliceLen;
llvm::SmallVector<int64_t, 2> indices(totalSizeOfShuffledElmnts);
for (auto [i, value] :
llvm::enumerate(mask.getAsValueRange<IntegerAttr>())) {
int64_t v = value.getZExtValue();
std::iota(indices.begin() + shuffleSliceLen * i,
indices.begin() + shuffleSliceLen * (i + 1),
shuffleSliceLen * v);
}
rewriter.replaceOpWithNewOp<vector::ShuffleOp>(
shuffleOp, dstType, vec1, vec2, rewriter.getI64ArrayAttr(indices));
return success();
}
private:
unsigned targetVectorBitWidth;
};
/// This pattern converts the ExtractOp to a ShuffleOp that works on a
/// linearized vector.
/// Following,
/// vector.extract %source [ position ]
/// is converted to :
/// %source_1d = vector.shape_cast %source
/// %out_1d = vector.shuffle %source_1d, %source_1d [ shuffle_indices_1d ]
/// %out_nd = vector.shape_cast %out_1d
/// `shuffle_indices_1d` is computed using the position of the original extract.
struct LinearizeVectorExtract final
: public OpConversionPattern<vector::ExtractOp> {
using OpConversionPattern::OpConversionPattern;
LinearizeVectorExtract(
const TypeConverter &typeConverter, MLIRContext *context,
unsigned targetVectBitWidth = std::numeric_limits<unsigned>::max(),
PatternBenefit benefit = 1)
: OpConversionPattern(typeConverter, context, benefit),
targetVectorBitWidth(targetVectBitWidth) {}
LogicalResult
matchAndRewrite(vector::ExtractOp extractOp, OpAdaptor adaptor,
ConversionPatternRewriter &rewriter) const override {
Type dstTy = getTypeConverter()->convertType(extractOp.getType());
assert(!(extractOp.getVector().getType().isScalable() ||
cast<VectorType>(dstTy).isScalable()) &&
"scalable vectors are not supported.");
if (!isLessThanTargetBitWidth(extractOp, targetVectorBitWidth))
return rewriter.notifyMatchFailure(
extractOp, "Can't flatten since targetBitWidth <= OpSize");
// Dynamic position is not supported.
if (extractOp.hasDynamicPosition())
return rewriter.notifyMatchFailure(extractOp,
"dynamic position is not supported.");
llvm::ArrayRef<int64_t> shape = extractOp.getVector().getType().getShape();
int64_t size = extractOp.getVector().getType().getNumElements();
// Compute linearized offset.
int64_t linearizedOffset = 0;
llvm::ArrayRef<int64_t> offsets = extractOp.getStaticPosition();
for (auto [i, off] : llvm::enumerate(offsets)) {
size /= shape[i];
linearizedOffset += offsets[i] * size;
}
llvm::SmallVector<int64_t, 2> indices(size);
std::iota(indices.begin(), indices.end(), linearizedOffset);
rewriter.replaceOpWithNewOp<vector::ShuffleOp>(
extractOp, dstTy, adaptor.getVector(), adaptor.getVector(),
rewriter.getI64ArrayAttr(indices));
return success();
}
private:
unsigned targetVectorBitWidth;
};
} // namespace
void mlir::vector::populateVectorLinearizeTypeConversionsAndLegality(
TypeConverter &typeConverter, RewritePatternSet &patterns,
ConversionTarget &target, unsigned targetBitWidth) {
typeConverter.addConversion([](VectorType type) -> std::optional<Type> {
if (!isLinearizableVector(type))
return type;
return VectorType::get(type.getNumElements(), type.getElementType(),
type.isScalable());
});
auto materializeCast = [](OpBuilder &builder, Type type, ValueRange inputs,
Location loc) -> Value {
if (inputs.size() != 1 || !isa<VectorType>(inputs.front().getType()) ||
!isa<VectorType>(type))
return nullptr;
return builder.create<vector::ShapeCastOp>(loc, type, inputs.front());
};
typeConverter.addArgumentMaterialization(materializeCast);
typeConverter.addSourceMaterialization(materializeCast);
typeConverter.addTargetMaterialization(materializeCast);
target.markUnknownOpDynamicallyLegal(
[=](Operation *op) -> std::optional<bool> {
if ((isa<arith::ConstantOp>(op) ||
op->hasTrait<OpTrait::Vectorizable>())) {
return (isLessThanTargetBitWidth(op, targetBitWidth)
? typeConverter.isLegal(op)
: true);
}
return std::nullopt;
});
patterns.add<LinearizeConstant, LinearizeVectorizable>(
typeConverter, patterns.getContext(), targetBitWidth);
}
void mlir::vector::populateVectorLinearizeShuffleLikeOpsPatterns(
TypeConverter &typeConverter, RewritePatternSet &patterns,
ConversionTarget &target, unsigned int targetBitWidth) {
target.addDynamicallyLegalOp<vector::ShuffleOp>(
[=](vector::ShuffleOp shuffleOp) -> bool {
return isLessThanTargetBitWidth(shuffleOp, targetBitWidth)
? (typeConverter.isLegal(shuffleOp) &&
cast<mlir::VectorType>(shuffleOp.getResult().getType())
.getRank() == 1)
: true;
});
patterns.add<LinearizeVectorShuffle, LinearizeVectorExtract,
LinearizeVectorExtractStridedSlice>(
typeConverter, patterns.getContext(), targetBitWidth);
}