1/*
2 * Copyright 2010, The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef _FRAMEWORKS_COMPILE_SLANG_SLANG_RS_METADATA_SPEC_H_  // NOLINT
18#define _FRAMEWORKS_COMPILE_SLANG_SLANG_RS_METADATA_SPEC_H_
19
20// Design Philosophy:
21//  Expensive encoding but cheap decoding process.
22//
23// 1. A string table concatenates ALL strings (including '\0' in t)
24// 2. A string index table which is an integer array containg the offset
25//    to access each string in the string table.
26// 3. All ->name field in RSType/RSVar/RSFunction now refer to an index in the
27//    string index table for offset lookup.
28// 4. RSType information is encoded as a byte stream like:
29//
30//                    [RSType #1][RSType #2] ... [RSType #N]
31//
32//    All ->type or ->base_type in RS*Type now becomes an index to RSType array.
33//
34// 5. RSVar => an string table index plus RSType array index
35// 6. RSFunction => an string table index
36
37namespace llvm {
38  class Module;
39}
40
41// Forward declaration
42union RSType;
43
44struct RSVar {
45  const char *name;  // variable name
46  const union RSType *type;
47};
48
49struct RSFunction {
50  const char *name;  // function name
51};
52
53// Opaque pointer
54typedef int RSMetadataEncoder;
55
56// Create a context associated with M for encoding metadata.
57RSMetadataEncoder *CreateRSMetadataEncoder(llvm::Module *M);
58
59// Encode V as a metadata in M. Return 0 if every thing goes well.
60int RSEncodeVarMetadata(RSMetadataEncoder *E, const RSVar *V);
61// Encode F as a metadata in M. Return 0 if every thing goes well.
62int RSEncodeFunctionMetadata(RSMetadataEncoder *E, const RSFunction *F);
63
64// Release the memory allocation of Encoder without flushing things.
65void DestroyRSMetadataEncoder(RSMetadataEncoder *E);
66
67// Flush metadata in E to its associated module and Destroy it. Return 0 if
68// every thing goes well. This will also call the DestroyRSMetadataEncoder().
69int FinalizeRSMetadataEncoder(RSMetadataEncoder *E);
70
71// TODO(slang): Decoder
72struct RSMetadata {
73  unsigned num_vars;
74  unsigned num_funcs;
75
76  RSVar *vars;
77  RSFunction *funcs;
78
79  void *context;
80};
81
82// struct RSMetadata *RSDecodeMetadata(llvm::Module *M);
83// void RSReleaseMetadata(struct RSMetadata *MD);
84
85#endif  // _FRAMEWORKS_COMPILE_SLANG_SLANG_RS_METADATA_SPEC_H_  NOLINT
86