xref: /aosp_15_r20/external/pytorch/torch/csrc/autograd/functions/basic_ops.cpp (revision da0073e96a02ea20f0ac840b70461e3646d07c45)
1 #include <torch/csrc/autograd/functions/basic_ops.h>
2 
3 #include <torch/csrc/autograd/function.h>
4 #include <torch/csrc/autograd/functions/utils.h>
5 #include <torch/csrc/autograd/variable.h>
6 #include <torch/csrc/dynamo/compiled_autograd.h>
7 
8 #include <ATen/ATen.h>
9 
10 #include <memory>
11 #include <utility>
12 
13 namespace torch::autograd {
14 
apply(variable_list && inputs)15 auto Error::apply(variable_list&& inputs) -> variable_list {
16   throw std::runtime_error(msg);
17 }
18 
compiled_args(CompiledNodeArgs & args)19 void Error::compiled_args(CompiledNodeArgs& args) {
20   // throw the error durring collect, the graph won't get compiled
21   apply(variable_list());
22 }
23 
apply_with_saved(const variable_list & inputs,SwapSavedVariables & saved)24 variable_list Error::apply_with_saved(
25     const variable_list& inputs,
26     SwapSavedVariables& saved) {
27   TORCH_INTERNAL_ASSERT(false, "unreachable");
28 }
29 
apply(variable_list && inputs)30 auto DelayedError::apply(variable_list&& inputs) -> variable_list {
31   tensor_list outputs;
32   outputs.reserve(inputs.size());
33   for (auto& var : inputs) {
34     // FIXME: share version counters
35     outputs.emplace_back(var.defined() ? var.tensor_data() : at::Tensor());
36   }
37   return wrap_outputs(inputs, std::move(outputs), [&](edge_list&& next_edges) {
38     return std::make_shared<Error>(msg, std::move(next_edges));
39   });
40 }
41 
apply(variable_list && inputs)42 auto UndefinedGrad::apply(variable_list&& inputs) -> variable_list {
43   tensor_list outputs;
44   outputs.reserve(inputs.size());
45   for (auto& var : inputs) {
46     outputs.emplace_back(
47         var.defined() ? var.clone().tensor_data() : at::Tensor());
48   }
49   return wrap_outputs(inputs, std::move(outputs), [&](edge_list&& next_edges) {
50     return std::make_shared<UndefinedGradBackward>(std::move(next_edges));
51   });
52 }
53 
apply(variable_list && output_grads)54 auto UndefinedGradBackward::apply(variable_list&& output_grads)
55     -> variable_list {
56   tensor_list input_grads;
57   output_grads.reserve(input_grads.size());
58   for (auto& grad : output_grads) {
59     (void)grad; // Suppress unused variable warning
60     input_grads.emplace_back();
61   }
62   return input_grads;
63 }
64 
apply(variable_list && grads)65 auto Identity::apply(variable_list&& grads) -> variable_list {
66   return std::move(grads);
67 }
68 
compiled_args(CompiledNodeArgs & args)69 void GraphRoot::compiled_args(CompiledNodeArgs& args) {
70   args.collect(outputs);
71 }
apply_with_saved(const variable_list & inputs,SwapSavedVariables & saved)72 variable_list GraphRoot::apply_with_saved(
73     const variable_list& inputs,
74     SwapSavedVariables& saved) {
75   saved.before(outputs);
76   variable_list result(outputs);
77   saved.after(outputs);
78   return result;
79 }
80 
81 } // namespace torch::autograd
82