1 /* This file contains subroutine used by the C front-end to construct GENERIC.
2 Copyright (C) 2000-2016 Free Software Foundation, Inc.
3 Written by Benjamin Chelf (chelf@codesourcery.com).
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
11
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 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 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "c-common.h"
25 #include "tree-iterator.h"
26
27 /* Create an empty statement tree rooted at T. */
28
29 tree
push_stmt_list(void)30 push_stmt_list (void)
31 {
32 tree t;
33 t = alloc_stmt_list ();
34 vec_safe_push (stmt_list_stack, t);
35 return t;
36 }
37
38 /* Finish the statement tree rooted at T. */
39
40 tree
pop_stmt_list(tree t)41 pop_stmt_list (tree t)
42 {
43 tree u = NULL_TREE;
44
45 /* Pop statement lists until we reach the target level. The extra
46 nestings will be due to outstanding cleanups. */
47 while (1)
48 {
49 u = stmt_list_stack->pop ();
50 if (!stmt_list_stack->is_empty ())
51 {
52 tree x = stmt_list_stack->last ();
53 STATEMENT_LIST_HAS_LABEL (x) |= STATEMENT_LIST_HAS_LABEL (u);
54 }
55 if (t == u)
56 break;
57 }
58
59 gcc_assert (u != NULL_TREE);
60
61 /* If the statement list is completely empty, just return it. This is
62 just as good small as build_empty_stmt, with the advantage that
63 statement lists are merged when they appended to one another. So
64 using the STATEMENT_LIST avoids pathological buildup of EMPTY_STMT_P
65 statements. */
66 if (TREE_SIDE_EFFECTS (t))
67 {
68 tree_stmt_iterator i = tsi_start (t);
69
70 /* If the statement list contained exactly one statement, then
71 extract it immediately. */
72 if (tsi_one_before_end_p (i))
73 {
74 u = tsi_stmt (i);
75 tsi_delink (&i);
76 free_stmt_list (t);
77 t = u;
78 }
79 }
80
81 return t;
82 }
83
84 /* Build a generic statement based on the given type of node and
85 arguments. Similar to `build_nt', except that we set
86 EXPR_LOCATION to LOC. */
87 /* ??? This should be obsolete with the lineno_stmt productions
88 in the grammar. */
89
90 tree
build_stmt(location_t loc,enum tree_code code,...)91 build_stmt (location_t loc, enum tree_code code, ...)
92 {
93 tree ret;
94 int length, i;
95 va_list p;
96 bool side_effects;
97
98 /* This function cannot be used to construct variably-sized nodes. */
99 gcc_assert (TREE_CODE_CLASS (code) != tcc_vl_exp);
100
101 va_start (p, code);
102
103 ret = make_node (code);
104 TREE_TYPE (ret) = void_type_node;
105 length = TREE_CODE_LENGTH (code);
106 SET_EXPR_LOCATION (ret, loc);
107
108 /* TREE_SIDE_EFFECTS will already be set for statements with
109 implicit side effects. Here we make sure it is set for other
110 expressions by checking whether the parameters have side
111 effects. */
112
113 side_effects = false;
114 for (i = 0; i < length; i++)
115 {
116 tree t = va_arg (p, tree);
117 if (t && !TYPE_P (t))
118 side_effects |= TREE_SIDE_EFFECTS (t);
119 TREE_OPERAND (ret, i) = t;
120 }
121
122 TREE_SIDE_EFFECTS (ret) |= side_effects;
123
124 va_end (p);
125 return ret;
126 }
127
128 /* Build a REALPART_EXPR or IMAGPART_EXPR, according to CODE, from ARG. */
129
130 tree
build_real_imag_expr(location_t location,enum tree_code code,tree arg)131 build_real_imag_expr (location_t location, enum tree_code code, tree arg)
132 {
133 tree ret;
134 tree arg_type = TREE_TYPE (arg);
135
136 gcc_assert (code == REALPART_EXPR || code == IMAGPART_EXPR);
137
138 if (TREE_CODE (arg_type) == COMPLEX_TYPE)
139 {
140 ret = build1 (code, TREE_TYPE (TREE_TYPE (arg)), arg);
141 SET_EXPR_LOCATION (ret, location);
142 }
143 else if (INTEGRAL_TYPE_P (arg_type) || SCALAR_FLOAT_TYPE_P (arg_type))
144 {
145 ret = (code == REALPART_EXPR
146 ? arg
147 : omit_one_operand_loc (location, arg_type,
148 integer_zero_node, arg));
149 }
150 else
151 {
152 error_at (location, "wrong type argument to %s",
153 code == REALPART_EXPR ? "__real" : "__imag");
154 ret = error_mark_node;
155 }
156
157 return ret;
158 }
159