1/* Copyright 2018 The TensorFlow Authors. All Rights Reserved.
2
3Licensed under the Apache License, Version 2.0 (the "License");
4you may not use this file except in compliance with the License.
5You may obtain a copy of the License at
6
7 http://www.apache.org/licenses/LICENSE-2.0
8
9Unless required by applicable law or agreed to in writing, software
10distributed under the License is distributed on an "AS IS" BASIS,
11WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12See the License for the specific language governing permissions and
13limitations under the License.
14==============================================================================*/
15
16#include "tensorflow/core/kernels/host_constant_op.h"
17
18#include "tensorflow/core/framework/allocator.h"
19#include "tensorflow/core/framework/op_kernel.h"
20#include "tensorflow/core/framework/types.h"
21#include "tensorflow/core/lib/core/status.h"
22#include "tensorflow/core/platform/logging.h"
23#include "tensorflow/core/platform/macros.h"
24
25namespace tensorflow {
26
27_HostConstantOp::_HostConstantOp(OpKernelConstruction* ctx)
28 : OpKernel(ctx), tensor_(ctx->output_type(0)) {
29 const TensorProto* proto = nullptr;
30 AllocatorAttributes alloc_attr;
31 alloc_attr.set_on_host(true);
32 OP_REQUIRES_OK(ctx, ctx->GetAttr("value", &proto));
33 OP_REQUIRES_OK(
34 ctx, ctx->device()->MakeTensorFromProto(*proto, alloc_attr, &tensor_));
35 OP_REQUIRES(
36 ctx, ctx->output_type(0) == tensor_.dtype(),
37 errors::InvalidArgument("Type mismatch between value (",
38 DataTypeString(tensor_.dtype()), ") and dtype (",
39 DataTypeString(ctx->output_type(0)), ")"));
40}
41
42void _HostConstantOp::Compute(OpKernelContext* ctx) {
43 ctx->set_output(0, tensor_);
44}
45
46// A special DEVICE_DEFAULT kernel for int32.
47// TODO(b/25387198): Also enable int32 in device memory. This kernel
48// registration requires all int32 inputs and outputs to be in host memory.
49REGISTER_KERNEL_BUILDER(Name("Const")
50 .Device(DEVICE_DEFAULT)
51 .HostMemory("output")
52 .TypeConstraint<int32>("dtype"),
53 _HostConstantOp);
54
55// HostConst: forced to generate output on the host.
56REGISTER_KERNEL_BUILDER(Name("HostConst").Device(DEVICE_CPU), _HostConstantOp);
57REGISTER_KERNEL_BUILDER(
58 Name("HostConst").Device(DEVICE_DEFAULT).HostMemory("output"),
59 _HostConstantOp);
60
61} // end namespace tensorflow
62
63