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#include "tensorflow/core/framework/function.h"
#include "tensorflow/core/lib/core/errors.h"
namespace tensorflow {
typedef FunctionDefHelper FDH;
Status ReluGrad(const AttrSlice& attrs, FunctionDef* g) {
// clang-format off
*g = FDH::Define(
// Arg defs
{"x: T", "dy: T"},
// Ret val defs
{"dx: T"},
// Attr defs
{{"T: {float, double}"}},
// Nodes
{
{{"dx"}, "ReluGrad", {"dy", "x"}, {{"T", "$T"}}}
});
// clang-format on
return Status::OK();
}
REGISTER_OP_GRADIENT("Relu", ReluGrad);
Status CrossEntropyGrad(const AttrSlice& attrs, FunctionDef* g) {
// clang-format off
*g = FDH::Define(
// Arg defs
{"features: T", "labels: T", "dcost_dloss: T", "donotcare: T"},
// Ret val defs
{"dcost_dfeatures: T", "dcost_dlabels: T"},
// Attr defs
{{"T: {float, double}"}},
// Nodes
{
// _, dloss_dfeatures = CrossEntropy(features, labels)
{{"donotcare_loss", "dloss_dfeatures"}, "CrossEntropy",
{"features", "labels"}, {{"T", "$T"}}},
// dcost_dloss is of shape [batch_size].
// dcost_dloss_mat is of shape [batch_size, 1].
FDH::Const("neg1", -1),
{{"dcost_dloss_mat"}, "ExpandDims", {"dcost_dloss", "neg1"},
{{"T", "$T"}}},
// chain rule: dcost/dfeatures = dcost/dloss * dloss/dfeatures
{{"dcost_dfeatures"}, "Mul", {"dcost_dloss_mat", "dloss_dfeatures"},
{{"T", "$T"}}},
{{"dcost_dlabels"}, "ZerosLike", {"labels"}, {{"T", "$T"}}},
});
// clang-format on
return Status::OK();
}
REGISTER_OP_GRADIENT("CrossEntropy", CrossEntropyGrad);
} // end namespace tensorflow
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