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#ifdef WITH_PYTHON
#include <Python.h>
#endif
#include <torch/script.h>
#include "cpu/scatter_cpu.h"
#include "macros.h"
#include "utils.h"
#ifdef WITH_CUDA
#include "cuda/scatter_cuda.h"
#endif
#ifdef _WIN32
#ifdef WITH_PYTHON
#ifdef WITH_CUDA
PyMODINIT_FUNC PyInit__scatter_cuda(void) { return NULL; }
#else
PyMODINIT_FUNC PyInit__scatter_cpu(void) { return NULL; }
#endif
#endif
#endif
torch::Tensor broadcast(torch::Tensor src, torch::Tensor other, int64_t dim) {
if (src.dim() == 1)
for (auto i = 0; i < dim; i++)
src = src.unsqueeze(0);
for (auto i = src.dim(); i < other.dim(); i++)
src = src.unsqueeze(-1);
src = src.expand(other.sizes().vec());
return src;
}
std::tuple<torch::Tensor, torch::optional<torch::Tensor>>
scatter_fw(torch::Tensor src, torch::Tensor index, int64_t dim,
torch::optional<torch::Tensor> optional_out,
torch::optional<int64_t> dim_size, std::string reduce) {
if (src.device().is_cuda()) {
#ifdef WITH_CUDA
return scatter_cuda(src, index, dim, optional_out, dim_size, reduce);
#else
AT_ERROR("Not compiled with CUDA support");
#endif
} else {
return scatter_cpu(src, index, dim, optional_out, dim_size, reduce);
}
}
using torch::autograd::AutogradContext;
using torch::autograd::Variable;
using torch::autograd::variable_list;
class ScatterSum : public torch::autograd::Function<ScatterSum> {
public:
static variable_list forward(AutogradContext *ctx, Variable src,
Variable index, int64_t dim,
torch::optional<Variable> optional_out,
torch::optional<int64_t> dim_size) {
dim = dim < 0 ? src.dim() + dim : dim;
ctx->saved_data["dim"] = dim;
ctx->saved_data["src_shape"] = src.sizes();
index = broadcast(index, src, dim);
auto result = scatter_fw(src, index, dim, optional_out, dim_size, "sum");
auto out = std::get<0>(result);
ctx->save_for_backward({index});
if (optional_out.has_value())
ctx->mark_dirty({optional_out.value()});
return {out};
}
static variable_list backward(AutogradContext *ctx, variable_list grad_outs) {
auto grad_out = grad_outs[0];
auto saved = ctx->get_saved_variables();
auto index = saved[0];
auto dim = ctx->saved_data["dim"].toInt();
auto src_shape = list2vec(ctx->saved_data["src_shape"].toIntList());
auto grad_in = torch::gather(grad_out, dim, index, false);
return {grad_in, Variable(), Variable(), Variable(), Variable()};
}
};
class ScatterMul : public torch::autograd::Function<ScatterMul> {
public:
static variable_list forward(AutogradContext *ctx, Variable src,
Variable index, int64_t dim,
torch::optional<Variable> optional_out,
torch::optional<int64_t> dim_size) {
dim = dim < 0 ? src.dim() + dim : dim;
ctx->saved_data["dim"] = dim;
ctx->saved_data["src_shape"] = src.sizes();
index = broadcast(index, src, dim);
auto result = scatter_fw(src, index, dim, optional_out, dim_size, "mul");
auto out = std::get<0>(result);
ctx->save_for_backward({src, index, out});
if (optional_out.has_value())
ctx->mark_dirty({optional_out.value()});
return {out};
}
static variable_list backward(AutogradContext *ctx, variable_list grad_outs) {
auto grad_out = grad_outs[0];
auto saved = ctx->get_saved_variables();
auto src = saved[0];
auto index = saved[1];
auto out = saved[2];
auto dim = ctx->saved_data["dim"].toInt();
auto src_shape = list2vec(ctx->saved_data["src_shape"].toIntList());
auto grad_in = torch::gather(grad_out * out, dim, index, false).div_(src);
grad_in.masked_fill_(grad_in.isnan(), 0);
return {grad_in, Variable(), Variable(), Variable(), Variable()};
}
};
class ScatterMean : public torch::autograd::Function<ScatterMean> {
public:
static variable_list forward(AutogradContext *ctx, Variable src,
Variable index, int64_t dim,
torch::optional<Variable> optional_out,
torch::optional<int64_t> dim_size) {
dim = dim < 0 ? src.dim() + dim : dim;
ctx->saved_data["dim"] = dim;
ctx->saved_data["src_shape"] = src.sizes();
auto old_index = index;
index = broadcast(index, src, dim);
auto result = scatter_fw(src, index, dim, optional_out, dim_size, "sum");
auto out = std::get<0>(result);
auto ones = torch::ones(old_index.sizes(), src.options());
result = scatter_fw(ones, old_index,
old_index.dim() <= dim ? old_index.dim() - 1 : dim,
torch::nullopt, out.size(dim), "sum");
auto count = std::get<0>(result);
count.masked_fill_(count < 1, 1);
count = broadcast(count, out, dim);
if (out.is_floating_point())
out.true_divide_(count);
else
out.div_(count, "floor");
ctx->save_for_backward({index, count});
if (optional_out.has_value())
ctx->mark_dirty({optional_out.value()});
return {out};
}
static variable_list backward(AutogradContext *ctx, variable_list grad_outs) {
auto grad_out = grad_outs[0];
auto saved = ctx->get_saved_variables();
auto index = saved[0];
auto count = saved[1];
auto dim = ctx->saved_data["dim"].toInt();
auto src_shape = list2vec(ctx->saved_data["src_shape"].toIntList());
count = torch::gather(count, dim, index, false);
auto grad_in = torch::gather(grad_out, dim, index, false);
grad_in.true_divide_(count);
return {grad_in, Variable(), Variable(), Variable(), Variable()};
}
};
class ScatterMin : public torch::autograd::Function<ScatterMin> {
public:
static variable_list forward(AutogradContext *ctx, Variable src,
Variable index, int64_t dim,
torch::optional<Variable> optional_out,
torch::optional<int64_t> dim_size) {
dim = dim < 0 ? src.dim() + dim : dim;
ctx->saved_data["dim"] = dim;
ctx->saved_data["src_shape"] = src.sizes();
index = broadcast(index, src, dim);
auto result = scatter_fw(src, index, dim, optional_out, dim_size, "min");
auto out = std::get<0>(result);
auto arg_out = std::get<1>(result).value();
ctx->save_for_backward({index, arg_out});
ctx->mark_non_differentiable({arg_out});
if (optional_out.has_value())
ctx->mark_dirty({optional_out.value()});
return {out, arg_out};
}
static variable_list backward(AutogradContext *ctx, variable_list grad_outs) {
auto grad_out = grad_outs[0];
auto saved = ctx->get_saved_variables();
auto index = saved[0];
auto arg_out = saved[1];
auto dim = ctx->saved_data["dim"].toInt();
auto src_shape = list2vec(ctx->saved_data["src_shape"].toIntList());
src_shape[dim] += 1;
auto grad_in = torch::zeros(src_shape, grad_out.options());
grad_in.scatter_(dim, arg_out, grad_out);
grad_in = grad_in.narrow(dim, 0, src_shape[dim] - 1);
return {grad_in, Variable(), Variable(), Variable(), Variable()};
}
};
class ScatterMax : public torch::autograd::Function<ScatterMax> {
public:
static variable_list forward(AutogradContext *ctx, Variable src,
Variable index, int64_t dim,
torch::optional<Variable> optional_out,
torch::optional<int64_t> dim_size) {
dim = dim < 0 ? src.dim() + dim : dim;
ctx->saved_data["dim"] = dim;
ctx->saved_data["src_shape"] = src.sizes();
index = broadcast(index, src, dim);
auto result = scatter_fw(src, index, dim, optional_out, dim_size, "max");
auto out = std::get<0>(result);
auto arg_out = std::get<1>(result).value();
ctx->save_for_backward({index, arg_out});
ctx->mark_non_differentiable({arg_out});
if (optional_out.has_value())
ctx->mark_dirty({optional_out.value()});
return {out, arg_out};
}
static variable_list backward(AutogradContext *ctx, variable_list grad_outs) {
auto grad_out = grad_outs[0];
auto saved = ctx->get_saved_variables();
auto index = saved[0];
auto arg_out = saved[1];
auto dim = ctx->saved_data["dim"].toInt();
auto src_shape = list2vec(ctx->saved_data["src_shape"].toIntList());
src_shape[dim] += 1;
auto grad_in = torch::zeros(src_shape, grad_out.options());
grad_in.scatter_(dim, arg_out, grad_out);
grad_in = grad_in.narrow(dim, 0, src_shape[dim] - 1);
return {grad_in, Variable(), Variable(), Variable(), Variable()};
}
};
SCATTER_API torch::Tensor
scatter_sum(torch::Tensor src, torch::Tensor index, int64_t dim,
torch::optional<torch::Tensor> optional_out,
torch::optional<int64_t> dim_size) {
return ScatterSum::apply(src, index, dim, optional_out, dim_size)[0];
}
SCATTER_API torch::Tensor
scatter_mul(torch::Tensor src, torch::Tensor index, int64_t dim,
torch::optional<torch::Tensor> optional_out,
torch::optional<int64_t> dim_size) {
return ScatterMul::apply(src, index, dim, optional_out, dim_size)[0];
}
SCATTER_API torch::Tensor
scatter_mean(torch::Tensor src, torch::Tensor index, int64_t dim,
torch::optional<torch::Tensor> optional_out,
torch::optional<int64_t> dim_size) {
return ScatterMean::apply(src, index, dim, optional_out, dim_size)[0];
}
SCATTER_API std::tuple<torch::Tensor, torch::Tensor>
scatter_min(torch::Tensor src, torch::Tensor index, int64_t dim,
torch::optional<torch::Tensor> optional_out,
torch::optional<int64_t> dim_size) {
auto result = ScatterMin::apply(src, index, dim, optional_out, dim_size);
return std::make_tuple(result[0], result[1]);
}
SCATTER_API std::tuple<torch::Tensor, torch::Tensor>
scatter_max(torch::Tensor src, torch::Tensor index, int64_t dim,
torch::optional<torch::Tensor> optional_out,
torch::optional<int64_t> dim_size) {
auto result = ScatterMax::apply(src, index, dim, optional_out, dim_size);
return std::make_tuple(result[0], result[1]);
}
static auto registry = torch::RegisterOperators()
.op("torch_scatter::scatter_sum", &scatter_sum)
.op("torch_scatter::scatter_mul", &scatter_mul)
.op("torch_scatter::scatter_mean", &scatter_mean)
.op("torch_scatter::scatter_min", &scatter_min)
.op("torch_scatter::scatter_max", &scatter_max);
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