1 /* Iterator routines for manipulating GENERIC tree statement list. -*- C++ -*-
2 Copyright (C) 2003-2023 Free Software Foundation, Inc.
3 Contributed by Andrew MacLeod <amacleod@redhat.com>
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
20
21
22 /* This file is dependent upon the implementation of tree's. It provides an
23 abstract interface to the tree objects such that if all tree creation and
24 manipulations are done through this interface, we can easily change the
25 implementation of tree's, and not impact other code. */
26
27 #ifndef GCC_TREE_ITERATOR_H
28 #define GCC_TREE_ITERATOR_H 1
29
30 /* Iterator object for GENERIC or GIMPLE TREE statements. */
31
32 struct tree_stmt_iterator {
33 struct tree_statement_list_node *ptr;
34 tree container;
35
36 /* No need for user-defined constructors, the implicit definitions (or
37 aggregate initialization) are fine. */
38
39 bool operator== (tree_stmt_iterator b) const
40 { return b.ptr == ptr && b.container == container; }
41 bool operator!= (tree_stmt_iterator b) const { return !(*this == b); }
42 tree_stmt_iterator &operator++ () { ptr = ptr->next; return *this; }
43 tree_stmt_iterator &operator-- () { ptr = ptr->prev; return *this; }
44 tree_stmt_iterator operator++ (int)
45 { tree_stmt_iterator x = *this; ++*this; return x; }
46 tree_stmt_iterator operator-- (int)
47 { tree_stmt_iterator x = *this; --*this; return x; }
48 tree &operator* () { return ptr->stmt; }
49 tree operator* () const { return ptr->stmt; }
50 };
51
52 inline tree_stmt_iterator
53 tsi_start (tree t)
54 {
55 tree_stmt_iterator i;
56
57 i.ptr = STATEMENT_LIST_HEAD (t);
58 i.container = t;
59
60 return i;
61 }
62
63 inline tree_stmt_iterator
64 tsi_last (tree t)
65 {
66 tree_stmt_iterator i;
67
68 i.ptr = STATEMENT_LIST_TAIL (t);
69 i.container = t;
70
71 return i;
72 }
73
74 inline bool
75 tsi_end_p (tree_stmt_iterator i)
76 {
77 return i.ptr == NULL;
78 }
79
80 inline bool
81 tsi_one_before_end_p (tree_stmt_iterator i)
82 {
83 return i.ptr != NULL && i.ptr->next == NULL;
84 }
85
86 inline void
87 tsi_next (tree_stmt_iterator *i)
88 {
89 ++(*i);
90 }
91
92 inline void
93 tsi_prev (tree_stmt_iterator *i)
94 {
95 --(*i);
96 }
97
98 inline tree *
99 tsi_stmt_ptr (tree_stmt_iterator i)
100 {
101 return &(*i);
102 }
103
104 inline tree
105 tsi_stmt (tree_stmt_iterator i)
106 {
107 return *i;
108 }
109
110 /* Make tree_stmt_iterator work as a C++ range, e.g.
111 for (tree stmt : tsi_range (stmt_list)) { ... } */
112 class tsi_range
113 {
114 tree t;
115 public:
116 tsi_range (tree t): t(t) { }
117 tree_stmt_iterator begin() const { return tsi_start (t); }
118 tree_stmt_iterator end() const { return { nullptr, t }; }
119 };
120
121 enum tsi_iterator_update
122 {
123 TSI_NEW_STMT, /* Only valid when single statement is added, move
124 iterator to it. */
125 TSI_SAME_STMT, /* Leave the iterator at the same statement. */
126 TSI_CHAIN_START, /* Only valid when chain of statements is added, move
127 iterator to the first statement in the chain. */
128 TSI_CHAIN_END, /* Only valid when chain of statements is added, move
129 iterator to the last statement in the chain. */
130 TSI_CONTINUE_LINKING /* Move iterator to whatever position is suitable for
131 linking other statements/chains of statements in
132 the same direction. */
133 };
134
135 extern void tsi_link_before (tree_stmt_iterator *, tree,
136 enum tsi_iterator_update);
137 extern void tsi_link_after (tree_stmt_iterator *, tree,
138 enum tsi_iterator_update);
139
140 extern void tsi_delink (tree_stmt_iterator *);
141
142 extern tree alloc_stmt_list (void);
143 extern void free_stmt_list (tree);
144 extern void append_to_statement_list (tree, tree *);
145 extern void append_to_statement_list_force (tree, tree *);
146 extern tree expr_first (tree);
147 extern tree expr_last (tree);
148 extern tree expr_single (tree);
149
150 #endif /* GCC_TREE_ITERATOR_H */