1/* Struct-reorg optimization.
2   Copyright (C) 2002, 2003-2007, 2008, 2009 Free Software Foundation, Inc.
3   Contributed by Olga Golovanevsky <olga@il.ibm.com>
4
5This file is part of GCC.
6
7GCC is free software; you can redistribute it and/or modify
8under the terms of the GNU General Public License as published by
9the Free Software Foundation; either version 3 of the License, or
10(at your option) any later version.
11
12GCC is distributed in the hope that it will be useful,
13but WITHOUT ANY WARRANTY; without even the implied warranty of
14MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15GNU General Public License for more details.
16
17You should have received a copy of the GNU General Public License
18along with GCC; see the file COPYING3.  If not see
19<http://www.gnu.org/licenses/>.  */
20
21#ifndef IPA_STRUCT_REORG_H
22#define IPA_STRUCT_REORG_H
23
24/* This file contains data structures and interfaces required
25   for struct-reorg optimizations.  */
26
27/* An access site of the structure field.
28   We consider an access to be of the following form:
29
30   D.2166_21 = i.6_20 * 8;
31   D.2167_22 = (struct str_t *) D.2166_21;
32   D.2168_24 = D.2167_22 + p.5_23;
33   D.2169_25 = D.2168_24->b;
34*/
35
36struct field_access_site
37{
38  /* Statement in which the access site occurs.  */
39  gimple stmt;           /* D.2169_25 = D.2168_24->b;  */
40  tree comp_ref;         /* D.2168_24->b  */
41  tree field_decl;       /* b */
42  tree ref;              /* D.2168_24  */
43  tree num;              /* i.6_20  */
44  tree offset;           /* D2167_22  */
45  tree base;             /* p.5_23  */
46  gimple ref_def_stmt;   /* D.2168_24 = D.2167_22 + p.5_23;  */
47  gimple cast_stmt;      /* D.2167_22 = (struct str_t *) D.2166_21;
48                            This statement is not always present.  */
49};
50
51/* A non-field structure access site.  */
52struct access_site
53{
54  /* A statement in which the access site occurs.  */
55  gimple stmt;
56  /* A list of structure variables in the access site.  */
57  VEC (tree, heap) *vars;
58};
59
60/* A field of the structure.  */
61struct field_entry
62{
63  /* A field index.  */
64  int index;
65  /* Number of times the field is accessed (according to profiling).  */
66  gcov_type count;
67  tree decl;
68  /* A type of a new structure this field belongs to.  */
69  tree field_mapping;
70  htab_t acc_sites;
71};
72
73/* This structure represents a result of the structure peeling.
74   The original structure is decomposed into substructures, or clusters.  */
75struct field_cluster
76{
77  /* A bitmap of field indices. The set bit indicates that the field
78     corresponding to it is a part of this cluster.  */
79  sbitmap fields_in_cluster;
80  struct field_cluster *sibling;
81};
82
83/* An information about an individual structure type (RECORD_TYPE) required
84   by struct-reorg optimizations to perform a transformation.  */
85struct data_structure
86{
87
88  /* A main variant of the structure type.  */
89  tree decl;
90
91  /* Number of fields in the structure.  */
92  int num_fields;
93
94  /* A structure access count collected through profiling.  */
95  gcov_type count;
96
97  /* An array of the structure fields, indexed by field ID.  */
98  struct field_entry *fields;
99
100  /* Non-field accesses of the structure.  */
101  htab_t accs;
102
103  /* A data structure representing a reorganization decision.  */
104  struct field_cluster *struct_clustering;
105
106  /* New types to replace the original structure type.  */
107  VEC(tree, heap) *new_types;
108};
109
110typedef struct data_structure * d_str;
111
112#endif /* IPA_STRUCT_REORG_H */
113