1/*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19
20/*!
21 * \file meta_ref.h
22 * \brief A reference into the metadata section of the Relay text format.
23 */
24
25#ifndef TVM_PARSER_META_REF_H_
26#define TVM_PARSER_META_REF_H_
27
28#include <tvm/ir/attrs.h>
29#include <tvm/parser/parser.h>
30#include <tvm/relay/expr.h>
31#include <tvm/relay/function.h>
32
33#include <string>
34
35namespace tvm {
36namespace parser {
37
38using namespace relay;
39
40/*!
41 * \brief Options for allocating storage.
42 */
43struct MetaRefAttrs : public tvm::AttrsNode<MetaRefAttrs> {
44 tvm::String node_type_key;
45 uint64_t node_index;
46
47 TVM_DECLARE_ATTRS(MetaRefAttrs, "relay.attrs.MetaRefAttrs") {
48 TVM_ATTR_FIELD(node_type_key)
49 .describe("The type_key representing the type of the node referenced.");
50 TVM_ATTR_FIELD(node_index).describe("The index into the type specific node array.");
51 }
52};
53
54/*! \brief A reference to a "meta-expression".
55 *
56 * In the text format we allow referencing metadata which
57 * uses a compact serialization that proceeds the main
58 * program body.
59 *
60 * We can reference this table using an expression of
61 * the form `meta[Type][index]`.
62 *
63 * We must later resolve these references to actual in-memory
64 * AST nodes but this requires first parsing the full program
65 * then expanding these temporary AST nodes into their corresponding
66 * nodes.
67 *
68 * For example the nth large constant will be pretty-printed as meta[relay.Constant][n]
69 * with its compact binary serialization residing in the metadata section at the end
70 * of the program.
71 *
72 * \param type_key The type key of the object in the meta section.
73 * \param node_index The index into that subfield.
74 * \returns The meta table reference.
75 */
76Expr MetaRef(std::string type_key, uint64_t node_index);
77
78relay::Function ExpandMetaRefs(const MetaTable& meta_table, const relay::Function& func);
79IRModule ExpandMetaRefs(const MetaTable& meta_table, const IRModule& mod);
80
81} // namespace parser
82} // namespace tvm
83
84#endif // TVM_PARSER_META_REF_H_
85