ai-content-maker/.venv/Lib/site-packages/torch/include/ATen/cuda/CUDAApplyUtils.cuh

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#pragma once
#include <ATen/cuda/ApplyGridUtils.cuh>
#include <ATen/cuda/detail/IndexUtils.cuh>
#include <ATen/core/TensorBase.h>
#include <ATen/ceil_div.h>
#include <ATen/cuda/Atomic.cuh>
#include <ATen/cuda/CUDAContext.h>
#include <c10/macros/Macros.h>
#include <ATen/native/Copy.h>
#include <math.h>
//
// This file contains pointwise operation functions and kernels that
// work on both contiguous and non-contiguous tensor arguments of
// arbitrary (up to MAX_CUTORCH_DIMS) dimensioned arguments without
// copying or temporary storage.
//
/*
NOTE [ CUDA_tensor_applyN helpers ]
The following CUDA_tensor_applyN (where N currently can be 1, 2, 3, or 4)
functions apply a pointwise operator to N tensor(s).
The calling convention is
1. The template arguments should be, sequentially,
- First N typename args specify the scalar types of each of the N tensors.
- (Optional) `int step` arg specifies the number of elements processed
together at the same time.
Default is 1.
- A usually omitted (i.e., inferred) typename arg specifies the type of the
function/functor applied on `N * step` values in each iteration of each
CUDA thread.
2. The arguments should be, sequentially,
- N tensors
- op: a function/functor that processes `N * step` values at the same time.
- If `step == 1`, it must have signature
`void(*)(scalar1_t&, scalar2_t&, ..., scalarN_t&)`, where
`scalar*_t`s are the first N typename template args, and the inputs
are the `N` values from the `N` tensors retrieved at a common index.
- Otherwise, it must must have signature
void(*)(int n, scalar1_t&, scalar1_t&, ..., scalar1_t&, // repeat `step` times
scalar2_t&, scalar2_t&, ..., scalar2_t&, // repeat `step` times
...,
scalarN_t&, scalarN_t&, ..., scalarN_t&) // repeat `step` times
Different from `step == 1` case, it processes `N * step` values taken
from `step` common indices. Moreover, the first input `n` represents the
number of valid indices (it will always have `0 < n <= step`). It will
almost always be `step`, but at the boundary we may not have full `step`
elements and `n` can be a lesser value.
E.g., if `step == 4` and `N == 2`, `op` could be
[](int n, scalar1_t &u1, scalar1_t &u2, scalar1_t &u3, scalar1_t &u4,
scalar2_t &v1, scalar2_t &v2, scalar2_t &v3, scalar2_t &v4) {
// Only process u1, ..., un and v1, ..., vn.
// So if `n == 3`, `u4` and `v4` need not to be considered.
}
In both cases, the references can actually be const, but at least one of
them should be non-const in order to write the output.
- (Optional, but recommended) N TensorArgType args that specify for each
tensor whether `op` reads AND writes ] (i.e., TensorArgType::ReadWrite),
or only reads (i.e., TensorArgType::ReadOnly).
Default is TensorArgType::ReadWrite for first Tensor, and
TensorArgType::ReadOnly for the rest.
E.g.,
to compute a = b^2 for a and b of same dtype, we can call
CUDA_tensor_apply2<scalar, scalar>(
a, b,
[] __device__ (scalar &a_val, const scalar &b_val) { a_val = b_val * b_val; }
);
to work on 2 values at the same time, we can call
CUDA_tensor_apply2<scalar1, scalar2, 2>(
a, b,
[] __device__ (int n, scalar1 &a_val1, scalar1 &a_val2,
const scalar2 &b_val1, const scalar2 &b_val2) {
// call special vectorized op here, or just do elementwise and enjoy unrolling...
// if n == 1, only process a_val1 and b_val1
}
);
*/
namespace at::cuda {
// TODO: combine with TensorArg? So far that's been for debugging, and this is functional...
enum class TensorArgType { ReadWrite, ReadOnly };
namespace {
// Rearrange dimensions for pointwise operations so that strides are in
// decreasing order as much as possible, so that kernels have better memory
// access patterns.
//
// For example, consider a binary operation on two "transposed" 2-dim tensors:
// sizes: 256 512
// aInfo->strides: 1 256
// bInfo->strides: 1 256
//
// Given this, each concurrent memory access inside kernelPointwiseApply2() is
// exactly 256 elements apart, resulting in poor performance.
//
// This function exchanges dimensions so that memory access is contiguous:
// sizes: 512 256
// aInfo->strides: 256 1
// bInfo->strides: 256 1
//
// (Actually, it becomes even better because now collapseDims() can turn each
// input into one contiguous array.)
//
// In general, given M (<=4) TensorInfo's with N dimensions, we can view each
// strides[i] (0 <= i < N) as an M-tuple. Given each pair i < j, we exchange
// strides[i] and [j] if
// (1) strides[i][k] < strides[j][k] for some k (0 <= k < M)
// (exchanging them will benefit input #k), and
// (2) strides[i][k] <= strieds[j][k] for all k
// (exchanging them will not make any input worse).
template <typename T1, typename IndexType,
typename T2 = void, typename T3 = void, typename T4 = void>
inline void rearrangeDims(detail::TensorInfo<T1, IndexType>* aInfo,
detail::TensorInfo<T2, IndexType>* bInfo = nullptr,
detail::TensorInfo<T3, IndexType>* cInfo = nullptr,
detail::TensorInfo<T4, IndexType>* dInfo = nullptr) {
int numInfos = 1;
int dims = aInfo->dims;
IndexType *sizes[4] = { aInfo->sizes, };
IndexType *strides[4] = { aInfo->strides, };
if (bInfo != nullptr) {
++numInfos;
if (bInfo->dims != dims) return;
sizes[1] = bInfo->sizes;
strides[1] = bInfo->strides;
}
if (cInfo != nullptr) {
++numInfos;
if (cInfo->dims != dims) return;
sizes[2] = cInfo->sizes;
strides[2] = cInfo->strides;
}
if (dInfo != nullptr) {
++numInfos;
if (dInfo->dims != dims) return;
sizes[3] = dInfo->sizes;
strides[3] = dInfo->strides;
}
// Bail out if sizes do not match: we are using "deprecated pointwise
// behavior" among tensors of different shapes but same number of elements.
for (int i = 1; i < numInfos; ++i) {
for (int j = 0; j < dims; ++j) {
if (sizes[i][j] != sizes[0][j]) return;
}
}
for (int i = 0; i < dims - 1; ++i) {
// No need to consider dimensions of size 1.
if (sizes[0][i] == 1) continue;
for (int j = i + 1; j < dims; ++j) {
if (sizes[0][j] == 1) continue;
// Compare the relative sizes of strides between dim #i and dim #j.
bool hasIncreasingStrides = false;
bool hasDecreasingStrides = false;
for (int k = 0; k < numInfos; k++) {
IndexType stride_i = strides[k][i];
IndexType stride_j = strides[k][j];
if (stride_i < stride_j) {
hasIncreasingStrides = true;
} else if (stride_i > stride_j) {
hasDecreasingStrides = true;
}
}
if (hasIncreasingStrides && !hasDecreasingStrides) {
for (int k = 0; k < numInfos; k++) {
IndexType size = sizes[k][i];
sizes[k][i] = sizes[k][j];
sizes[k][j] = size;
IndexType stride = strides[k][i];
strides[k][i] = strides[k][j];
strides[k][j] = stride;
}
}
}
}
}
// The `remaining_steps` argument is used to support Op that operates on
// multiple elements at the same time. Generally, the strategy of ApplyOpN is to
// 1. Initialize `remaining_steps = step`, where `step` is the template arg of
// CUDA_tensor_applyN helpers. The input arg `n` to `apply()` represents the
// number of elements in bound for this call. It will almost always equal to
// `step` except at boundaries.
// 2. If `remaining_steps > 0` convert the current linearIndex to offset (if in
// bound), and recursively call `ApplyOpN` with `remaining_steps - 1`.
// 3. At `remaining_steps = 0`,
// if `step = 1`, call `op(tensor1_val, tensor2_val, ...)`;
// if `step > 1`, call `op(n, tensor1_val1, tensor1_val2, ..., tesor1_valstep,
// tensor2_val1, tensor2_val2, ..., tesor2_valstep,
// ...
// tensorN_val1, tensorN_val2, ..., tesorN_valstep);`
//
// See NOTE [ CUDA_tensor_applyN helpers ] above for how Op may look like.
template <typename Op,
typename scalar,
typename IndexType,
int ADims,
int remaining_steps,
typename... Offsets>
struct ApplyOp1 {
__device__ __forceinline__
static void apply(detail::TensorInfo<scalar, IndexType> &a, const Op &op, int n,
IndexType linearIndex, Offsets... aOffsets) {
// Convert `linearIndex` into an offset of `a`
const IndexType aOffset = sizeof...(Offsets) < n ?
detail::IndexToOffset<scalar, IndexType, ADims>::get(linearIndex, a) : 0;
ApplyOp1<Op, scalar, IndexType, ADims, remaining_steps - 1, const IndexType, Offsets...>::apply(
a, op, n, linearIndex + 1, aOffsets..., aOffset
);
}
};
// Specialize `step=1` case (i.e., `remaining_steps=0` and `len(Offsets)=1`).
// We don't need to pass in how many elements need to processed in this case.
template <typename Op,
typename scalar,
typename IndexType,
int ADims,
typename Offset>
struct ApplyOp1<Op, scalar, IndexType, ADims, 0, Offset> {
__device__ __forceinline__
static void apply(detail::TensorInfo<scalar, IndexType> &a, const Op &op,
int n, IndexType linearIndex, Offset offset) {
op(a.data[offset]);
}
};
template <typename Op,
typename scalar,
typename IndexType,
int ADims,
typename... Offsets>
struct ApplyOp1<Op, scalar, IndexType, ADims, 0, Offsets...> {
__device__ __forceinline__
static void apply(detail::TensorInfo<scalar, IndexType> &a, const Op &op, int n,
IndexType linearIndex, Offsets... offsets) {
op(n, a.data[offsets]...);
}
};
template <typename Op,
typename scalar,
typename IndexType,
int ADims,
int step>
#if __CUDA_ARCH__ >= 350 || defined(USE_ROCM)
C10_LAUNCH_BOUNDS_2(AT_APPLY_THREADS_PER_BLOCK, AT_APPLY_BLOCKS_PER_SM)
#endif
__global__ void kernelPointwiseApply1(detail::TensorInfo<scalar, IndexType> a,
IndexType totalElements, const Op op) {
for (IndexType linearIndex = (blockIdx.x * blockDim.x + threadIdx.x) * step;
linearIndex < totalElements;
linearIndex += gridDim.x * blockDim.x * step) {
ApplyOp1<Op, scalar, IndexType, ADims, step>::apply(
a, op, ::min(step, static_cast<int>(totalElements - linearIndex)), linearIndex);
}
}
template <typename Op,
typename scalar1,
typename scalar2,
typename IndexType,
int ADims,
int BDims,
int remaining_steps,
typename... Offsets>
struct ApplyOp2 {
__device__ __forceinline__
static void apply(detail::TensorInfo<scalar1, IndexType> &a,
detail::TensorInfo<scalar2, IndexType> &b,
const Op &op, int64_t n, IndexType linearIndex,
Offsets... aOffsets, Offsets... bOffsets) {
// Convert `linearIndex` into an offset of `a`
const IndexType aOffset = static_cast<int64_t>(sizeof...(Offsets)) < n ?
detail::IndexToOffset<scalar1, IndexType, ADims>::get(linearIndex, a) : 0;
// Convert `linearIndex` into an offset of `b`
const IndexType bOffset = static_cast<int64_t>(sizeof...(Offsets)) < n ?
detail::IndexToOffset<scalar2, IndexType, BDims>::get(linearIndex, b) : 0;
ApplyOp2<Op, scalar1, scalar2, IndexType, ADims, BDims, remaining_steps - 1, const IndexType, Offsets...>::apply(
a, b, op, n, linearIndex + 1, aOffsets..., aOffset, bOffsets..., bOffset
);
}
};
// Specialize `step=1` case (i.e., `remaining_steps=0` and `len(Offsets)=1`).
// We don't need to pass in how many elements need to processed in this case.
template <typename Op,
typename scalar1,
typename scalar2,
typename IndexType,
int ADims,
int BDims,
typename Offset>
struct ApplyOp2<Op, scalar1, scalar2, IndexType, ADims, BDims, 0, Offset> {
__device__ __forceinline__
static void apply(detail::TensorInfo<scalar1, IndexType> &a,
detail::TensorInfo<scalar2, IndexType> &b,
const Op &op, int /*n*/, IndexType /*linearIndex*/,
Offset aOffset, Offset bOffset) {
op(a.data[aOffset], b.data[bOffset]);
}
};
template <typename Op,
typename scalar1,
typename scalar2,
typename IndexType,
int ADims,
int BDims,
typename... Offsets>
struct ApplyOp2<Op, scalar1, scalar2, IndexType, ADims, BDims, 0, Offsets...> {
__device__ __forceinline__
static void apply(detail::TensorInfo<scalar1, IndexType> &a,
detail::TensorInfo<scalar2, IndexType> &b,
const Op &op, int n, IndexType linearIndex,
Offsets... aOffsets, Offsets... bOffsets) {
op(n, a.data[aOffsets]..., b.data[bOffsets]...);
}
};
template <typename Op,
typename scalar1,
typename scalar2,
typename IndexType,
int ADims, int BDims,
int step,
int max_threads_per_block=AT_APPLY_THREADS_PER_BLOCK,
int min_blocks_per_sm=AT_APPLY_BLOCKS_PER_SM>
#if __CUDA_ARCH__ >= 350 || defined(USE_ROCM)
C10_LAUNCH_BOUNDS_2(max_threads_per_block, min_blocks_per_sm)
#endif
__global__ void
kernelPointwiseApply2(detail::TensorInfo<scalar1, IndexType> a,
detail::TensorInfo<scalar2, IndexType> b,
IndexType totalElements,
const Op op) {
for (IndexType linearIndex = (blockIdx.x * blockDim.x + threadIdx.x) * step;
linearIndex < totalElements;
linearIndex += gridDim.x * blockDim.x * step) {
ApplyOp2<Op, scalar1, scalar2, IndexType, ADims, BDims, step>::apply(
a, b, op, ::min(step, static_cast<int>(totalElements - linearIndex)),
linearIndex);
}
}
} // anonymous namespace
template <typename scalar1, typename scalar2, int step, typename Op,
int max_threads_per_block=AT_APPLY_THREADS_PER_BLOCK,
int min_blocks_per_sm=AT_APPLY_BLOCKS_PER_SM>
inline bool CUDA_tensor_apply2(at::TensorBase a,
at::TensorBase b,
const Op op,
TensorArgType aType = TensorArgType::ReadWrite,
TensorArgType bType = TensorArgType::ReadOnly) {
TORCH_CHECK(a.device().is_cuda() && b.device().is_cuda(),
"CUDA_tensor_apply2: Expected tensors to have CUDA DeviceType, but got "
"tensors with type ", a.device().type(), " and ", b.device().type());
int64_t totalElements = a.numel();
if (totalElements != b.numel()) {
return false;
}
if (a.dim() > MAX_TENSORINFO_DIMS ||
b.dim() > MAX_TENSORINFO_DIMS) {
return false;
}
if (a.numel() == 0) {
// Empty tensor; do nothing
return true;
}
const dim3 block = getApplyBlock(max_threads_per_block);
dim3 grid;
auto curDevice = current_device();
if (curDevice == -1) return false;
if (!getApplyGrid<step>(totalElements, grid, curDevice, max_threads_per_block)) {
return false;
}
/*
Expands readable/writable tensors whose indices may be "overlapped."
This ensures that each element of the tensor is operated on once and only
once.
*/
TensorBase oldA;
TensorBase oldB;
if (aType == TensorArgType::ReadWrite && detail::maybeOverlappingIndices(a)) {
// Must perform in contiguous space
oldA = std::exchange(a, a.contiguous());
}
if (bType == TensorArgType::ReadWrite && detail::maybeOverlappingIndices(b)) {
// Must perform in contiguous space
oldB = std::exchange(b, b.contiguous());
}
// It is possible that the tensor dimensions are able to be collapsed,
// and thus we can reduce the actual code complexity of the copy by
// exploiting this knowledge statically, since the div/mod is the
// most expensive part of the operation, more so than memory accesses.
// For instance, when copying a non-contiguous to a contiguous tensor
// (or vice versa), the contiguous tensor can be collapsed to one
// dimension, and the loop to translate the linear index to the array
// index can be similarly collapsed. That is what this unrolling is for.
#define HANDLE_CASE(TYPE, A, B) \
kernelPointwiseApply2<Op, \
scalar1, \
scalar2, \
TYPE, A, B, step, \
max_threads_per_block, \
min_blocks_per_sm> \
<<<grid, block, 0, at::cuda::getCurrentCUDAStream(curDevice)>>>( \
aInfo, bInfo, static_cast<TYPE>(totalElements), op); \
C10_CUDA_KERNEL_LAUNCH_CHECK();
#define HANDLE_B_CASE(TYPE, A, B) { \
switch (B) { \
case 1: \
HANDLE_CASE(TYPE, A, 1); \
break; \
case 2: \
HANDLE_CASE(TYPE, A, 2); \
break; \
default: \
HANDLE_CASE(TYPE, A, -1); \
break; \
} \
}
#define HANDLE_A_CASE(TYPE, A, B) { \
switch (A) { \
case 1: \
HANDLE_B_CASE(TYPE, 1, B); \
break; \
case 2: \
HANDLE_B_CASE(TYPE, 2, B); \
break; \
default: \
HANDLE_B_CASE(TYPE, -1, B); \
break; \
} \
}
if (detail::canUse32BitIndexMath(a) &&
detail::canUse32BitIndexMath(b)) {
detail::TensorInfo<scalar1, unsigned int> aInfo =
detail::getTensorInfo<scalar1, unsigned int>(a);
detail::TensorInfo<scalar2, unsigned int> bInfo =
detail::getTensorInfo<scalar2, unsigned int>(b);
rearrangeDims(&aInfo, &bInfo);
aInfo.collapseDims();
bInfo.collapseDims();
HANDLE_A_CASE(unsigned int, aInfo.dims, bInfo.dims);
} else {
detail::TensorInfo<scalar1, uint64_t> aInfo =
detail::getTensorInfo<scalar1, uint64_t>(a);
detail::TensorInfo<scalar2, uint64_t> bInfo =
detail::getTensorInfo<scalar2, uint64_t>(b);
rearrangeDims(&aInfo, &bInfo);
aInfo.collapseDims();
bInfo.collapseDims();
/*
Only instantiates the all 1D special case and the fallback all nD case for
large (64-bit indexed) tensors to reduce compilation time.
*/
if (aInfo.dims == 1 && bInfo.dims == 1) {
HANDLE_CASE(uint64_t, 1, 1);
} else {
HANDLE_CASE(uint64_t, -1, -1);
}
}
#undef HANDLE_CASE
#undef HANDLE_B_CASE
#undef HANDLE_A_CASE
if (oldA.defined()) {
at::native::copy_ignoring_overlaps(oldA, a);
}
if (oldB.defined()) {
at::native::copy_ignoring_overlaps(oldB, b);
}
return true;
}
/* Provides default step = 1 to CUDA_tensor_apply2. */
template <typename scalar1, typename scalar2, typename Op,
int max_threads_per_block=AT_APPLY_THREADS_PER_BLOCK,
int min_blocks_per_sm=AT_APPLY_BLOCKS_PER_SM>
inline bool CUDA_tensor_apply2(const at::TensorBase &a,
const at::TensorBase &b,
const Op op,
TensorArgType aType = TensorArgType::ReadWrite,
TensorArgType bType = TensorArgType::ReadOnly) {
return CUDA_tensor_apply2<scalar1, scalar2, 1, Op,
max_threads_per_block, min_blocks_per_sm>(a, b, op, aType, bType);
}
} // namespace at::cuda