aosp12/external/gemmlowp/public/map.h

142 lines
4.3 KiB
C++

// Copyright 2015 The Gemmlowp Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// map.h: a minimalist view-existing-buffer-as-a-matrix class,
// which is how gemmlowp interfaces with external matrix data.
#ifndef GEMMLOWP_PUBLIC_MAP_H_
#define GEMMLOWP_PUBLIC_MAP_H_
#include "../internal/common.h"
namespace gemmlowp {
// The two storage orders allowed to map buffers as matrices: ColMajor
// means column-major, RowMajor means row-major.
enum class MapOrder { ColMajor, RowMajor };
// A MatrixMap is a view of an existing buffer as a matrix. It does not own
// the buffer.
template <typename tScalar, MapOrder tOrder>
class MatrixMap {
public:
typedef tScalar Scalar;
static constexpr MapOrder kOrder = tOrder;
protected:
Scalar* data_; // not owned.
int rows_, cols_, stride_;
public:
MatrixMap() : data_(nullptr), rows_(0), cols_(0), stride_(0) {}
MatrixMap(Scalar* data, int rows, int cols)
: data_(data),
rows_(rows),
cols_(cols),
stride_(kOrder == MapOrder::ColMajor ? rows : cols) {}
MatrixMap(Scalar* data, int rows, int cols, int stride)
: data_(data), rows_(rows), cols_(cols), stride_(stride) {}
MatrixMap(const MatrixMap& other)
: data_(other.data_),
rows_(other.rows_),
cols_(other.cols_),
stride_(other.stride_) {}
int rows() const { return rows_; }
int cols() const { return cols_; }
int stride() const { return stride_; }
int rows_stride() const { return kOrder == MapOrder::ColMajor ? 1 : stride_; }
int cols_stride() const { return kOrder == MapOrder::RowMajor ? 1 : stride_; }
Scalar* data() const { return data_; }
Scalar* data(int row, int col) const {
return data_ + row * rows_stride() + col * cols_stride();
}
Scalar& operator()(int row, int col) const { return *data(row, col); }
MatrixMap block(int start_row, int start_col, int block_rows,
int block_cols) const {
assert(start_row >= 0);
assert(start_row + block_rows <= rows_);
assert(start_col >= 0);
assert(start_col + block_cols <= cols_);
return MatrixMap(data(start_row, start_col), block_rows, block_cols,
stride_);
}
};
enum class VectorShape { Col, Row };
// A VectorMap is a view of an existing buffer as a vector. It does not own
// the buffer.
template <typename tScalar, VectorShape tShape>
class VectorMap {
public:
typedef tScalar Scalar;
static constexpr VectorShape kShape = tShape;
protected:
Scalar* data_; // not owned.
int size_;
public:
VectorMap() : data_(nullptr), size_(0) {}
VectorMap(Scalar* data, int size) : data_(data), size_(size) {}
VectorMap(const VectorMap& other) : data_(other.data_), size_(other.size_) {}
int size() const { return size_; }
Scalar* data() const { return data_; }
Scalar* data(int index) const { return data_ + index; }
Scalar& operator()(int index) const { return *data(index); }
VectorMap block(int start, int len) const {
assert(start >= 0);
assert(start + len <= size_);
return VectorMap(data(start), len);
}
};
// A VectorDup is a (duplicated value) vector where all components are the same.
template <typename tScalar, VectorShape tShape>
class VectorDup {
public:
typedef tScalar Scalar;
static constexpr VectorShape kShape = tShape;
protected:
Scalar data_;
int size_;
public:
VectorDup() : data_(0), size_(0) {}
VectorDup(Scalar data, int size) : data_(data), size_(size) {}
VectorDup(const VectorDup& other) : data_(other.data_), size_(other.size_) {}
int size() const { return size_; }
Scalar& operator()(int) const { return data_; }
VectorDup block(int start, int len) const {
assert(start >= 0);
assert(start + len <= size_);
(void)start;
return VectorDup(data_, len);
}
};
} // namespace gemmlowp
#endif // GEMMLOWP_PUBLIC_MAP_H_