]>
Commit | Line | Data |
---|---|---|
4ee9c684 | 1 | /* Tree lowering pass. This pass gimplifies the tree representation built |
2 | by the C-based front ends. The structure of gimplified, or | |
3 | language-independent, trees is dictated by the grammar described in this | |
4 | file. | |
944a57c9 | 5 | Copyright (C) 2002, 2003, 2004, 2005, 2007, 2008 |
6 | Free Software Foundation, Inc. | |
4ee9c684 | 7 | Lowering of expressions contributed by Sebastian Pop <s.pop@laposte.net> |
8 | Re-written to support lowering of whole function trees, documentation | |
9 | and miscellaneous cleanups by Diego Novillo <dnovillo@redhat.com> | |
10 | ||
11 | This file is part of GCC. | |
12 | ||
13 | GCC is free software; you can redistribute it and/or modify it under | |
14 | the terms of the GNU General Public License as published by the Free | |
8c4c00c1 | 15 | Software Foundation; either version 3, or (at your option) any later |
4ee9c684 | 16 | version. |
17 | ||
18 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
19 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
20 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
21 | for more details. | |
22 | ||
23 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 24 | along with GCC; see the file COPYING3. If not see |
25 | <http://www.gnu.org/licenses/>. */ | |
4ee9c684 | 26 | |
27 | #include "config.h" | |
28 | #include "system.h" | |
29 | #include "coretypes.h" | |
30 | #include "tm.h" | |
31 | #include "tree.h" | |
4ee9c684 | 32 | #include "varray.h" |
33 | #include "c-tree.h" | |
34 | #include "c-common.h" | |
75a70cf9 | 35 | #include "gimple.h" |
4ee9c684 | 36 | #include "hard-reg-set.h" |
37 | #include "basic-block.h" | |
38 | #include "tree-flow.h" | |
39 | #include "tree-inline.h" | |
40 | #include "diagnostic.h" | |
41 | #include "langhooks.h" | |
42 | #include "langhooks-def.h" | |
43 | #include "flags.h" | |
44 | #include "rtl.h" | |
45 | #include "toplev.h" | |
46 | #include "tree-dump.h" | |
47 | #include "c-pretty-print.h" | |
48 | #include "cgraph.h" | |
49 | ||
50 | ||
51 | /* The gimplification pass converts the language-dependent trees | |
52 | (ld-trees) emitted by the parser into language-independent trees | |
53 | (li-trees) that are the target of SSA analysis and transformations. | |
54 | ||
55 | Language-independent trees are based on the SIMPLE intermediate | |
56 | representation used in the McCAT compiler framework: | |
57 | ||
58 | "Designing the McCAT Compiler Based on a Family of Structured | |
59 | Intermediate Representations," | |
60 | L. Hendren, C. Donawa, M. Emami, G. Gao, Justiani, and B. Sridharan, | |
61 | Proceedings of the 5th International Workshop on Languages and | |
62 | Compilers for Parallel Computing, no. 757 in Lecture Notes in | |
63 | Computer Science, New Haven, Connecticut, pp. 406-420, | |
64 | Springer-Verlag, August 3-5, 1992. | |
65 | ||
66 | http://www-acaps.cs.mcgill.ca/info/McCAT/McCAT.html | |
67 | ||
68 | Basically, we walk down gimplifying the nodes that we encounter. As we | |
69 | walk back up, we check that they fit our constraints, and copy them | |
70 | into temporaries if not. */ | |
71 | ||
4ee9c684 | 72 | /* Gimplification of statement trees. */ |
73 | ||
74 | /* Convert the tree representation of FNDECL from C frontend trees to | |
75 | GENERIC. */ | |
76 | ||
77 | void | |
78 | c_genericize (tree fndecl) | |
79 | { | |
3f5be5f4 | 80 | FILE *dump_orig; |
4ee9c684 | 81 | int local_dump_flags; |
82 | struct cgraph_node *cgn; | |
83 | ||
84 | /* Dump the C-specific tree IR. */ | |
3f5be5f4 | 85 | dump_orig = dump_begin (TDI_original, &local_dump_flags); |
86 | if (dump_orig) | |
4ee9c684 | 87 | { |
3f5be5f4 | 88 | fprintf (dump_orig, "\n;; Function %s", |
5135beeb | 89 | lang_hooks.decl_printable_name (fndecl, 2)); |
3f5be5f4 | 90 | fprintf (dump_orig, " (%s)\n", |
944a57c9 | 91 | (!DECL_ASSEMBLER_NAME_SET_P (fndecl) ? "null" |
92 | : IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (fndecl)))); | |
3f5be5f4 | 93 | fprintf (dump_orig, ";; enabled by -%s\n", dump_flag_name (TDI_original)); |
94 | fprintf (dump_orig, "\n"); | |
4ee9c684 | 95 | |
96 | if (local_dump_flags & TDF_RAW) | |
97 | dump_node (DECL_SAVED_TREE (fndecl), | |
3f5be5f4 | 98 | TDF_SLIM | local_dump_flags, dump_orig); |
4ee9c684 | 99 | else |
3f5be5f4 | 100 | print_c_tree (dump_orig, DECL_SAVED_TREE (fndecl)); |
101 | fprintf (dump_orig, "\n"); | |
4ee9c684 | 102 | |
3f5be5f4 | 103 | dump_end (TDI_original, dump_orig); |
4ee9c684 | 104 | } |
105 | ||
106 | /* Go ahead and gimplify for now. */ | |
4ee9c684 | 107 | gimplify_function_tree (fndecl); |
4ee9c684 | 108 | |
4ee9c684 | 109 | dump_function (TDI_generic, fndecl); |
110 | ||
111 | /* Genericize all nested functions now. We do things in this order so | |
112 | that items like VLA sizes are expanded properly in the context of | |
113 | the correct function. */ | |
114 | cgn = cgraph_node (fndecl); | |
115 | for (cgn = cgn->nested; cgn ; cgn = cgn->next_nested) | |
116 | c_genericize (cgn->decl); | |
117 | } | |
118 | ||
4ee9c684 | 119 | static void |
120 | add_block_to_enclosing (tree block) | |
121 | { | |
75a70cf9 | 122 | unsigned i; |
4ee9c684 | 123 | tree enclosing; |
75a70cf9 | 124 | gimple bind; |
125 | VEC(gimple, heap) *stack = gimple_bind_expr_stack (); | |
4ee9c684 | 126 | |
75a70cf9 | 127 | for (i = 0; VEC_iterate (gimple, stack, i, bind); i++) |
128 | if (gimple_bind_block (bind)) | |
4ee9c684 | 129 | break; |
130 | ||
75a70cf9 | 131 | enclosing = gimple_bind_block (bind); |
4ee9c684 | 132 | BLOCK_SUBBLOCKS (enclosing) = chainon (BLOCK_SUBBLOCKS (enclosing), block); |
133 | } | |
134 | ||
135 | /* Genericize a scope by creating a new BIND_EXPR. | |
136 | BLOCK is either a BLOCK representing the scope or a chain of _DECLs. | |
137 | In the latter case, we need to create a new BLOCK and add it to the | |
138 | BLOCK_SUBBLOCKS of the enclosing block. | |
139 | BODY is a chain of C _STMT nodes for the contents of the scope, to be | |
140 | genericized. */ | |
141 | ||
2363ef00 | 142 | tree |
e60a6f7b | 143 | c_build_bind_expr (location_t loc, tree block, tree body) |
4ee9c684 | 144 | { |
145 | tree decls, bind; | |
146 | ||
147 | if (block == NULL_TREE) | |
148 | decls = NULL_TREE; | |
149 | else if (TREE_CODE (block) == BLOCK) | |
150 | decls = BLOCK_VARS (block); | |
151 | else | |
152 | { | |
153 | decls = block; | |
154 | if (DECL_ARTIFICIAL (decls)) | |
155 | block = NULL_TREE; | |
156 | else | |
157 | { | |
158 | block = make_node (BLOCK); | |
159 | BLOCK_VARS (block) = decls; | |
160 | add_block_to_enclosing (block); | |
161 | } | |
162 | } | |
163 | ||
164 | if (!body) | |
e60a6f7b | 165 | body = build_empty_stmt (loc); |
2363ef00 | 166 | if (decls || block) |
4ee9c684 | 167 | { |
14ae0310 | 168 | bind = build3 (BIND_EXPR, void_type_node, decls, body, block); |
2363ef00 | 169 | TREE_SIDE_EFFECTS (bind) = 1; |
e60a6f7b | 170 | SET_EXPR_LOCATION (bind, loc); |
4ee9c684 | 171 | } |
172 | else | |
2363ef00 | 173 | bind = body; |
4ee9c684 | 174 | |
2363ef00 | 175 | return bind; |
4ee9c684 | 176 | } |
177 | ||
4ee9c684 | 178 | /* Gimplification of expression trees. */ |
179 | ||
75a70cf9 | 180 | /* Do C-specific gimplification on *EXPR_P. PRE_P and POST_P are as in |
181 | gimplify_expr. */ | |
4ee9c684 | 182 | |
183 | int | |
862f468c | 184 | c_gimplify_expr (tree *expr_p, gimple_seq *pre_p ATTRIBUTE_UNUSED, |
75a70cf9 | 185 | gimple_seq *post_p ATTRIBUTE_UNUSED) |
4ee9c684 | 186 | { |
187 | enum tree_code code = TREE_CODE (*expr_p); | |
188 | ||
862f468c | 189 | /* This is handled mostly by gimplify.c, but we have to deal with |
190 | not warning about int x = x; as it is a GCC extension to turn off | |
191 | this warning but only if warn_init_self is zero. */ | |
192 | if (code == DECL_EXPR | |
193 | && TREE_CODE (DECL_EXPR_DECL (*expr_p)) == VAR_DECL | |
194 | && !DECL_EXTERNAL (DECL_EXPR_DECL (*expr_p)) | |
195 | && !TREE_STATIC (DECL_EXPR_DECL (*expr_p)) | |
196 | && (DECL_INITIAL (DECL_EXPR_DECL (*expr_p)) == DECL_EXPR_DECL (*expr_p)) | |
197 | && !warn_init_self) | |
198 | TREE_NO_WARNING (DECL_EXPR_DECL (*expr_p)) = 1; | |
199 | ||
200 | return GS_UNHANDLED; | |
4ee9c684 | 201 | } |