Files
composable_kernel/include/ck_tile/host/host_tensor.hpp
Sami Remes 8f27f65d44 [rocm-libraries] ROCm/rocm-libraries#4594 (commit 1fce4cb)
[CK_TILE] MX GEMM non-preshuffled RCR layout

## Motivation

Implements a GEMM with MX scaling for fp4 and fp8 in non-preshuffled
layouts using async pipeline.

## Technical Details

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## Test Plan

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## Test Result

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## Submission Checklist

- [ ] Look over the contributing guidelines at
https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.
2026-03-10 20:12:43 +00:00

866 lines
28 KiB
C++

// Copyright (c) Advanced Micro Devices, Inc., or its affiliates.
// SPDX-License-Identifier: MIT
#pragma once
#include <algorithm>
#include <cassert>
#include <iostream>
#include <iomanip>
#include <numeric>
#include <utility>
#include <vector>
#include <functional>
#include <fstream>
#include "ck_tile/core.hpp"
#include "ck_tile/host/joinable_thread.hpp"
#include "ck_tile/host/ranges.hpp"
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wlifetime-safety-intra-tu-suggestions"
namespace ck_tile {
template <typename Range>
CK_TILE_HOST std::ostream& LogRange(std::ostream& os,
Range&& range,
std::string delim,
int precision = std::cout.precision(),
int width = 0)
{
bool first = true;
for(auto&& v : range)
{
if(first)
first = false;
else
os << delim;
os << std::setw(width) << std::setprecision(precision) << v;
}
return os;
}
template <typename T, typename Range>
CK_TILE_HOST std::ostream& LogRangeAsType(std::ostream& os,
Range&& range,
std::string delim,
int precision = std::cout.precision(),
int width = 0)
{
bool first = true;
for(auto&& v : range)
{
if(first)
first = false;
else
os << delim;
os << std::setw(width) << std::setprecision(precision) << static_cast<T>(v);
}
return os;
}
template <typename F, typename T, std::size_t... Is>
CK_TILE_HOST auto call_f_unpack_args_impl(F f, T args, std::index_sequence<Is...>)
{
return f(std::get<Is>(args)...);
}
template <typename F, typename T>
CK_TILE_HOST auto call_f_unpack_args(F f, T args)
{
constexpr std::size_t N = std::tuple_size<T>{};
return call_f_unpack_args_impl(f, args, std::make_index_sequence<N>{});
}
template <typename F, typename T, std::size_t... Is>
CK_TILE_HOST auto construct_f_unpack_args_impl(T args, std::index_sequence<Is...>)
{
return F(std::get<Is>(args)...);
}
template <typename F, typename T>
CK_TILE_HOST auto construct_f_unpack_args(F, T args)
{
constexpr std::size_t N = std::tuple_size<T>{};
return construct_f_unpack_args_impl<F>(args, std::make_index_sequence<N>{});
}
/**
* @brief Descriptor for tensors in host memory.
*
* HostTensorDescriptor manages the shape (dimensions) and memory layout (strides)
* of a tensor in host memory. It provides functionality to:
* - Store tensor dimensions and strides
* - Calculate default strides for contiguous memory layout
* - Convert multi-dimensional indices to linear memory offsets
* - Query tensor metadata (dimensions, element counts, etc.)
*
* The class supports both automatic stride calculation for contiguous memory layout
* and custom strides for more complex memory patterns.
*/
struct HostTensorDescriptor
{
HostTensorDescriptor() = default;
void CalculateStrides()
{
mStrides.clear();
mStrides.resize(mLens.size(), 0);
if(mStrides.empty())
return;
mStrides.back() = 1;
std::partial_sum(mLens.rbegin(),
mLens.rend() - 1,
mStrides.rbegin() + 1,
std::multiplies<std::size_t>());
}
template <typename X, typename = std::enable_if_t<std::is_convertible_v<X, std::size_t>>>
HostTensorDescriptor(const std::initializer_list<X>& lens) : mLens(lens.begin(), lens.end())
{
this->CalculateStrides();
}
template <typename Lengths,
typename = std::enable_if_t<
std::is_convertible_v<ck_tile::ranges::range_value_t<Lengths>, std::size_t>>>
HostTensorDescriptor(const Lengths& lens) : mLens(lens.begin(), lens.end())
{
this->CalculateStrides();
}
template <typename X,
typename Y,
typename = std::enable_if_t<std::is_convertible_v<X, std::size_t> &&
std::is_convertible_v<Y, std::size_t>>>
HostTensorDescriptor(const std::initializer_list<X>& lens,
const std::initializer_list<Y>& strides)
: mLens(lens.begin(), lens.end()), mStrides(strides.begin(), strides.end())
{
}
template <typename Lengths,
typename Strides,
typename = std::enable_if_t<
std::is_convertible_v<ck_tile::ranges::range_value_t<Lengths>, std::size_t> &&
std::is_convertible_v<ck_tile::ranges::range_value_t<Strides>, std::size_t>>>
HostTensorDescriptor(const Lengths& lens, const Strides& strides)
: mLens(lens.begin(), lens.end()), mStrides(strides.begin(), strides.end())
{
}
std::size_t get_num_of_dimension() const { return mLens.size(); }
/**
* @brief Calculates the total number of elements in the tensor.
*
* Computes the product of all dimension lengths to determine the
* total element count in the tensor.
*
* @pre The lengths array (mLens) and strides array (mStrides) must have
* the same size.
*
* @return The total number of elements in the tensor.
*/
std::size_t get_element_size() const
{
assert(mLens.size() == mStrides.size());
return std::accumulate(
mLens.begin(), mLens.end(), std::size_t{1}, std::multiplies<std::size_t>());
}
/**
* @brief Calculates the total element space required for the tensor in memory.
*
* This method computes the minimum size of contiguous memory needed to store
* all elements of the tensor, taking into account the tensor's dimensions and
* strides. The calculation is based on the formula: 1 + max((length_i - 1) * stride_i)
* across all dimensions.
*
* Dimensions with length 0 are skipped in this calculation.
*
* @return The size of the tensor's element space (number of elements).
*/
std::size_t get_element_space_size() const
{
std::size_t space = 1;
for(std::size_t i = 0; i < mLens.size(); ++i)
{
if(mLens[i] == 0)
continue;
space += (mLens[i] - 1) * mStrides[i];
}
return space;
}
std::size_t get_length(std::size_t dim) const { return mLens[dim]; }
const std::vector<std::size_t>& get_lengths() const { return mLens; }
std::size_t get_stride(std::size_t dim) const { return mStrides[dim]; }
const std::vector<std::size_t>& get_strides() const { return mStrides; }
/**
* @brief Calculates the linear offset from multi-dimensional indices.
*
* Converts a set of N-dimensional indices into a single linear offset by computing
* the inner product of the indices with the tensor's strides.
*
* @tparam Is Parameter pack of index types (should be convertible to std::size_t)
* @param is Variable number of indices, one for each dimension of the tensor
* @return std::size_t Linear offset corresponding to the given multi-dimensional indices
*
* @pre The number of indices must match the number of dimensions in the tensor
*/
template <typename... Is>
std::size_t GetOffsetFromMultiIndex(Is... is) const
{
assert(sizeof...(Is) == this->get_num_of_dimension());
std::initializer_list<std::size_t> iss{static_cast<std::size_t>(is)...};
return std::inner_product(iss.begin(), iss.end(), mStrides.begin(), std::size_t{0});
}
/**
* @brief Calculates the linear memory offset from a multi-dimensional index
*
* Computes the linear offset by performing an inner product between the provided
* multi-dimensional indices and the tensor's strides.
*
* @param iss Vector containing the multi-dimensional indices
* @return The calculated linear offset as a size_t
*/
std::size_t GetOffsetFromMultiIndex(const std::vector<std::size_t>& iss) const
{
return std::inner_product(iss.begin(), iss.end(), mStrides.begin(), std::size_t{0});
}
friend std::ostream& operator<<(std::ostream& os, const HostTensorDescriptor& desc)
{
os << "dim " << desc.get_num_of_dimension() << ", ";
os << "lengths {";
LogRange(os, desc.get_lengths(), ", ");
os << "}, ";
os << "strides {";
LogRange(os, desc.get_strides(), ", ");
os << "}";
return os;
}
private:
std::vector<std::size_t> mLens; ///< Lengths of each dimension
std::vector<std::size_t> mStrides; ///< Strides for each dimension
};
template <typename New2Old>
CK_TILE_HOST HostTensorDescriptor transpose_host_tensor_descriptor_given_new2old(
const HostTensorDescriptor& a, const New2Old& new2old)
{
std::vector<std::size_t> new_lengths(a.get_num_of_dimension());
std::vector<std::size_t> new_strides(a.get_num_of_dimension());
for(std::size_t i = 0; i < a.get_num_of_dimension(); i++)
{
new_lengths[i] = a.get_lengths()[new2old[i]];
new_strides[i] = a.get_strides()[new2old[i]];
}
return HostTensorDescriptor(new_lengths, new_strides);
}
template <typename F, typename... Xs>
struct ParallelTensorFunctor
{
F mF;
static constexpr std::size_t NDIM = sizeof...(Xs);
std::array<std::size_t, NDIM> mLens;
std::array<std::size_t, NDIM> mStrides;
std::size_t mN1d;
ParallelTensorFunctor(F f, Xs... xs) : mF(f), mLens({static_cast<std::size_t>(xs)...})
{
mStrides.back() = 1;
std::partial_sum(mLens.rbegin(),
mLens.rend() - 1,
mStrides.rbegin() + 1,
std::multiplies<std::size_t>());
mN1d = mStrides[0] * mLens[0];
}
std::array<std::size_t, NDIM> GetNdIndices(std::size_t i) const
{
std::array<std::size_t, NDIM> indices;
for(std::size_t idim = 0; idim < NDIM; ++idim)
{
indices[idim] = i / mStrides[idim];
i -= indices[idim] * mStrides[idim];
}
return indices;
}
void operator()(std::size_t num_thread = 1) const
{
std::size_t work_per_thread = (mN1d + num_thread - 1) / num_thread;
std::vector<joinable_thread> threads(num_thread);
for(std::size_t it = 0; it < num_thread; ++it)
{
std::size_t iw_begin = it * work_per_thread;
std::size_t iw_end = std::min((it + 1) * work_per_thread, mN1d);
auto f = [this, iw_begin, iw_end] {
for(std::size_t iw = iw_begin; iw < iw_end; ++iw)
{
call_f_unpack_args(this->mF, this->GetNdIndices(iw));
}
};
threads[it] = joinable_thread(f);
}
}
};
template <typename F, typename... Xs>
CK_TILE_HOST auto make_ParallelTensorFunctor(F f, Xs... xs)
{
return ParallelTensorFunctor<F, Xs...>(f, xs...);
}
template <typename T>
struct HostTensor
{
using Descriptor = HostTensorDescriptor;
using Data = std::vector<T>;
template <typename X>
HostTensor(std::initializer_list<X> lens) : mDesc(lens), mData(get_element_space_size())
{
}
template <typename X, typename Y>
HostTensor(std::initializer_list<X> lens, std::initializer_list<Y> strides)
: mDesc(lens, strides), mData(get_element_space_size())
{
}
template <typename Lengths>
HostTensor(const Lengths& lens) : mDesc(lens), mData(get_element_space_size())
{
}
template <typename Lengths, typename Strides>
HostTensor(const Lengths& lens, const Strides& strides)
: mDesc(lens, strides), mData(get_element_space_size())
{
}
HostTensor(const Descriptor& desc) : mDesc(desc), mData(get_element_space_size()) {}
template <typename OutT>
HostTensor<OutT> CopyAsType() const
{
HostTensor<OutT> ret(mDesc);
std::transform(mData.cbegin(), mData.cend(), ret.mData.begin(), [](auto value) {
return ck_tile::type_convert<OutT>(value);
});
return ret;
}
HostTensor() = delete;
HostTensor(const HostTensor&) = default;
HostTensor(HostTensor&&) = default;
~HostTensor() = default;
HostTensor& operator=(const HostTensor&) = default;
HostTensor& operator=(HostTensor&&) = default;
template <typename FromT>
explicit HostTensor(const HostTensor<FromT>& other) : HostTensor(other.template CopyAsType<T>())
{
}
std::size_t get_length(std::size_t dim) const { return mDesc.get_length(dim); }
decltype(auto) get_lengths() const { return mDesc.get_lengths(); }
std::size_t get_stride(std::size_t dim) const { return mDesc.get_stride(dim); }
decltype(auto) get_strides() const { return mDesc.get_strides(); }
std::size_t get_num_of_dimension() const { return mDesc.get_num_of_dimension(); }
std::size_t get_element_size() const { return mDesc.get_element_size(); }
std::size_t get_element_space_size() const
{
constexpr index_t PackedSize = ck_tile::numeric_traits<remove_cvref_t<T>>::PackedSize;
return mDesc.get_element_space_size() / PackedSize;
}
std::size_t get_element_space_size_in_bytes() const
{
return sizeof(T) * get_element_space_size();
}
void SetZero()
{
if constexpr(std::is_same_v<T, e8m0_t>)
std::fill(mData.begin(), mData.end(), e8m0_t{1.f});
else
std::fill(mData.begin(), mData.end(), 0);
}
template <typename F>
void ForEach_impl(F&& f, std::vector<size_t>& idx, size_t rank)
{
if(rank == mDesc.get_num_of_dimension())
{
f(*this, idx);
return;
}
// else
for(size_t i = 0; i < mDesc.get_lengths()[rank]; i++)
{
idx[rank] = i;
ForEach_impl(std::forward<F>(f), idx, rank + 1);
}
}
template <typename F>
void ForEach(F&& f)
{
std::vector<size_t> idx(mDesc.get_num_of_dimension(), 0);
ForEach_impl(std::forward<F>(f), idx, size_t(0));
}
template <typename F>
void ForEach_impl(const F&& f, std::vector<size_t>& idx, size_t rank) const
{
if(rank == mDesc.get_num_of_dimension())
{
f(*this, idx);
return;
}
// else
for(size_t i = 0; i < mDesc.get_lengths()[rank]; i++)
{
idx[rank] = i;
ForEach_impl(std::forward<const F>(f), idx, rank + 1);
}
}
template <typename F>
void ForEach(const F&& f) const
{
std::vector<size_t> idx(mDesc.get_num_of_dimension(), 0);
ForEach_impl(std::forward<const F>(f), idx, size_t(0));
}
template <typename G>
void GenerateTensorValue(G g, std::size_t num_thread = 1)
{
switch(mDesc.get_num_of_dimension())
{
case 1: {
auto f = [&](auto i) { (*this)(i) = g(i); };
make_ParallelTensorFunctor(f, mDesc.get_lengths()[0])(num_thread);
break;
}
case 2: {
auto f = [&](auto i0, auto i1) { (*this)(i0, i1) = g(i0, i1); };
make_ParallelTensorFunctor(f, mDesc.get_lengths()[0], mDesc.get_lengths()[1])(
num_thread);
break;
}
case 3: {
auto f = [&](auto i0, auto i1, auto i2) { (*this)(i0, i1, i2) = g(i0, i1, i2); };
make_ParallelTensorFunctor(f,
mDesc.get_lengths()[0],
mDesc.get_lengths()[1],
mDesc.get_lengths()[2])(num_thread);
break;
}
case 4: {
auto f = [&](auto i0, auto i1, auto i2, auto i3) {
(*this)(i0, i1, i2, i3) = g(i0, i1, i2, i3);
};
make_ParallelTensorFunctor(f,
mDesc.get_lengths()[0],
mDesc.get_lengths()[1],
mDesc.get_lengths()[2],
mDesc.get_lengths()[3])(num_thread);
break;
}
case 5: {
auto f = [&](auto i0, auto i1, auto i2, auto i3, auto i4) {
(*this)(i0, i1, i2, i3, i4) = g(i0, i1, i2, i3, i4);
};
make_ParallelTensorFunctor(f,
mDesc.get_lengths()[0],
mDesc.get_lengths()[1],
mDesc.get_lengths()[2],
mDesc.get_lengths()[3],
mDesc.get_lengths()[4])(num_thread);
break;
}
case 6: {
auto f = [&](auto i0, auto i1, auto i2, auto i3, auto i4, auto i5) {
(*this)(i0, i1, i2, i3, i4, i5) = g(i0, i1, i2, i3, i4, i5);
};
make_ParallelTensorFunctor(f,
mDesc.get_lengths()[0],
mDesc.get_lengths()[1],
mDesc.get_lengths()[2],
mDesc.get_lengths()[3],
mDesc.get_lengths()[4],
mDesc.get_lengths()[5])(num_thread);
break;
}
default: throw std::runtime_error("unspported dimension");
}
}
template <typename... Is>
std::size_t GetOffsetFromMultiIndex(Is... is) const
{
constexpr index_t PackedSize = ck_tile::numeric_traits<remove_cvref_t<T>>::PackedSize;
return mDesc.GetOffsetFromMultiIndex(is...) / PackedSize;
}
template <typename... Is>
T& operator()(Is... is)
{
return mData[GetOffsetFromMultiIndex(is...)];
}
template <typename... Is>
const T& operator()(Is... is) const
{
return mData[GetOffsetFromMultiIndex(is...)];
}
T& operator()(const std::vector<std::size_t>& idx)
{
return mData[GetOffsetFromMultiIndex(idx)];
}
const T& operator()(const std::vector<std::size_t>& idx) const
{
return mData[GetOffsetFromMultiIndex(idx)];
}
HostTensor<T> transpose(std::vector<size_t> axes = {}) const
{
if(axes.empty())
{
axes.resize(this->get_num_of_dimension());
std::iota(axes.rbegin(), axes.rend(), 0);
}
if(axes.size() != mDesc.get_num_of_dimension())
{
throw std::runtime_error(
"HostTensor::transpose(): size of axes must match tensor dimension");
}
std::vector<size_t> tlengths, tstrides;
for(const auto& axis : axes)
{
tlengths.push_back(get_lengths()[axis]);
tstrides.push_back(get_strides()[axis]);
}
HostTensor<T> ret(*this);
ret.mDesc = HostTensorDescriptor(tlengths, tstrides);
return ret;
}
HostTensor<T> transpose(std::vector<size_t> axes = {})
{
return const_cast<HostTensor<T> const*>(this)->transpose(axes);
}
typename Data::iterator begin() { return mData.begin(); }
typename Data::iterator end() { return mData.end(); }
typename Data::pointer data() { return mData.data(); }
typename Data::const_iterator begin() const { return mData.begin(); }
typename Data::const_iterator end() const { return mData.end(); }
typename Data::const_pointer data() const { return mData.data(); }
typename Data::size_type size() const { return mData.size(); }
T max() const { return *std::max_element(mData.begin(), mData.end()); }
// return a slice of this tensor
// for simplicity we just copy the data and return a new tensor
auto slice(std::vector<size_t> s_begin, std::vector<size_t> s_end) const
{
assert(s_begin.size() == s_end.size());
assert(s_begin.size() == get_num_of_dimension());
std::vector<size_t> s_len(s_begin.size());
std::transform(
s_end.begin(), s_end.end(), s_begin.begin(), s_len.begin(), std::minus<size_t>{});
HostTensor<T> sliced_tensor(s_len);
sliced_tensor.ForEach([&](auto& self, auto idx) {
std::vector<size_t> src_idx(idx.size());
std::transform(
idx.begin(), idx.end(), s_begin.begin(), src_idx.begin(), std::plus<size_t>{});
self(idx) = operator()(src_idx);
});
return sliced_tensor;
}
template <typename U = T>
auto AsSpan() const
{
constexpr std::size_t FromSize = sizeof(T);
constexpr std::size_t ToSize = sizeof(U);
using Element = std::add_const_t<std::remove_reference_t<U>>;
return ck_tile::span<Element>{reinterpret_cast<Element*>(data()),
size() * FromSize / ToSize};
}
template <typename U = T>
auto AsSpan()
{
constexpr std::size_t FromSize = sizeof(T);
constexpr std::size_t ToSize = sizeof(U);
using Element = std::remove_reference_t<U>;
return ck_tile::span<Element>{reinterpret_cast<Element*>(data()),
size() * FromSize / ToSize};
}
/**
* @brief Print only the first N elements of the tensor
*
* @param os Output stream to write to
* @param n Number of elements to print (default: 5)
* @return std::ostream& Reference to the output stream
*/
std::ostream& print_first_n(std::ostream& os, std::size_t n = 5) const
{
os << mDesc;
os << "[";
for(typename Data::size_type idx = 0; idx < std::min(n, mData.size()); ++idx)
{
if(0 < idx)
{
os << ", ";
}
if constexpr(std::is_same_v<T, bf16_t> || std::is_same_v<T, fp16_t> ||
std::is_same_v<T, fp8_t> || std::is_same_v<T, bf8_t>)
{
os << type_convert<float>(mData[idx]);
}
else if constexpr(std::is_same_v<T, ck_tile::pk_int4_t>)
{
auto unpacked = pk_int4_t_to_int8x2_t(mData[idx]);
os << "pk(" << static_cast<int>(unpacked[0]) << ", "
<< static_cast<int>(unpacked[1]) << ")";
}
else if constexpr(std::is_same_v<T, int8_t>)
{
os << static_cast<int>(mData[idx]);
}
else
{
os << mData[idx];
}
}
if(mData.size() > n)
{
os << ", ...";
}
os << "]";
return os;
}
friend std::ostream& operator<<(std::ostream& os, const HostTensor<T>& t)
{
os << t.mDesc;
os << "[";
for(typename Data::size_type idx = 0; idx < t.mData.size(); ++idx)
{
if(0 < idx)
{
os << ", ";
}
if constexpr(std::is_same_v<T, bf16_t> || std::is_same_v<T, fp16_t> ||
std::is_same_v<T, fp8_t> || std::is_same_v<T, bf8_t>)
{
os << type_convert<float>(t.mData[idx]) << " #### ";
}
else if constexpr(std::is_same_v<T, ck_tile::pk_int4_t>)
{
auto unpacked = pk_int4_t_to_int8x2_t(t.mData[idx]);
os << "pk(" << static_cast<int>(unpacked[0]) << ", "
<< static_cast<int>(unpacked[1]) << ") #### ";
}
else
{
os << t.mData[idx];
}
}
os << "]";
return os;
}
// read data from a file, as dtype
// the file could dumped from torch as (targeting tensor is t here)
// numpy.savetxt("f.txt", t.view(-1).numpy())
// numpy.savetxt("f.txt", t.cpu().view(-1).numpy()) # from cuda to cpu to save
// numpy.savetxt("f.txt", t.cpu().view(-1).numpy(), fmt="%d") # save as int
// will output f.txt, each line is a value
// dtype=float or int, internally will cast to real type
void loadtxt(std::string file_name, std::string dtype = "float")
{
std::ifstream file(file_name);
if(file.is_open())
{
std::string line;
index_t cnt = 0;
while(std::getline(file, line))
{
if(cnt >= static_cast<index_t>(mData.size()))
{
throw std::runtime_error(std::string("data read from file:") + file_name +
" is too big");
}
if(dtype == "float")
{
mData[cnt] = type_convert<T>(std::stof(line));
}
else if(dtype == "int" || dtype == "int32")
{
mData[cnt] = type_convert<T>(std::stoi(line));
}
cnt++;
}
file.close();
if(cnt < static_cast<index_t>(mData.size()))
{
std::cerr << "Warning! reading from file:" << file_name
<< ", does not match the size of this tensor" << std::endl;
}
}
else
{
// Print an error message to the standard error
// stream if the file cannot be opened.
throw std::runtime_error(std::string("unable to open file:") + file_name);
}
}
// can save to a txt file and read from torch as:
// torch.from_numpy(np.loadtxt('f.txt', dtype=np.int32/np.float32...)).view([...]).contiguous()
void savetxt(std::string file_name, std::string dtype = "float")
{
std::ofstream file(file_name);
if(file.is_open())
{
for(auto& itm : mData)
{
if(dtype == "float")
file << type_convert<float>(itm) << std::endl;
else if(dtype == "int")
file << type_convert<int>(itm) << std::endl;
else if(dtype == "int8_t")
file << static_cast<int>(type_convert<ck_tile::int8_t>(itm)) << std::endl;
else
// TODO: we didn't implement operator<< for all custom
// data types, here fall back to float in case compile error
file << type_convert<float>(itm) << std::endl;
}
file.close();
}
else
{
// Print an error message to the standard error
// stream if the file cannot be opened.
throw std::runtime_error(std::string("unable to open file:") + file_name);
}
}
Descriptor mDesc;
Data mData;
};
/**
* @brief Creates a host tensor descriptor with specified dimensions and layout
*
* Constructs a HostTensorDescriptor with appropriate strides based on whether the tensor
* layout is row-major or column-major. This is determined via the compile-time template
* parameter `is_row_major`.
*
* @tparam is_row_major Compile-time flag indicating if the layout is row-major (true) or
* column-major (false)
*
* @param row Number of rows in the tensor
* @param col Number of columns in the tensor
* @param stride Stride between adjacent rows (for row-major) or columns (for column-major)
*
* @return HostTensorDescriptor with shape {row, col} and strides:
* - For row-major: {stride, 1}
* - For column-major: {1, stride}
*/
template <bool is_row_major>
auto host_tensor_descriptor(std::size_t row,
std::size_t col,
std::size_t stride,
bool_constant<is_row_major>)
{
using namespace ck_tile::literals;
if constexpr(is_row_major)
{
return HostTensorDescriptor({row, col}, {stride, 1_uz});
}
else
{
return HostTensorDescriptor({row, col}, {1_uz, stride});
}
}
template <bool is_row_major>
auto get_default_stride(std::size_t row,
std::size_t col,
std::size_t stride,
bool_constant<is_row_major>)
{
if(stride == 0)
{
if constexpr(is_row_major)
{
return col;
}
else
{
return row;
}
}
else
return stride;
}
} // namespace ck_tile
#pragma clang diagnostic pop