1 /* Perform optimizations on tree structure.
2 Copyright (C) 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
3 Written by Mark Michell (mark@codesourcery.com).
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GCC is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
24 #include "coretypes.h"
29 #include "insn-config.h"
31 #include "integrate.h"
38 #include "tree-inline.h"
42 static tree calls_setjmp_r (tree *, int *, void *);
43 static void update_cloned_parm (tree, tree);
44 static void dump_function (enum tree_dump_index, tree);
46 /* Optimize the body of FN. */
49 optimize_function (tree fn)
51 dump_function (TDI_original, fn);
53 /* While in this function, we may choose to go off and compile
54 another function. For example, we might instantiate a function
55 in the hopes of inlining it. Normally, that wouldn't trigger any
56 actual RTL code-generation -- but it will if the template is
57 actually needed. (For example, if it's address is taken, or if
58 some other function already refers to the template.) If
59 code-generation occurs, then garbage collection will occur, so we
60 must protect ourselves, just as we do while building up the body
65 /* We do not inline thunks, as (a) the backend tries to optimize
66 the call to the thunkee, (b) tree based inlining breaks that
67 optimization, (c) virtual functions are rarely inlineable,
68 and (d) TARGET_ASM_OUTPUT_MI_THUNK is there to DTRT anyway. */
69 && !DECL_THUNK_P (fn))
71 optimize_inline_calls (fn);
73 dump_function (TDI_inlined, fn);
76 /* Undo the call to ggc_push_context above. */
79 dump_function (TDI_optimized, fn);
82 /* Called from calls_setjmp_p via walk_tree. */
85 calls_setjmp_r (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
86 void *data ATTRIBUTE_UNUSED)
88 /* We're only interested in FUNCTION_DECLS. */
89 if (TREE_CODE (*tp) != FUNCTION_DECL)
92 return setjmp_call_p (*tp) ? *tp : NULL_TREE;
95 /* Returns nonzero if FN calls `setjmp' or some other function that
96 can return more than once. This function is conservative; it may
97 occasionally return a nonzero value even when FN does not actually
101 calls_setjmp_p (tree fn)
103 return walk_tree_without_duplicates (&DECL_SAVED_TREE (fn),
108 /* CLONED_PARM is a copy of CLONE, generated for a cloned constructor
109 or destructor. Update it to ensure that the source-position for
110 the cloned parameter matches that for the original, and that the
111 debugging generation code will be able to find the original PARM. */
114 update_cloned_parm (tree parm, tree cloned_parm)
116 DECL_ABSTRACT_ORIGIN (cloned_parm) = parm;
118 /* We may have taken its address. */
119 TREE_ADDRESSABLE (cloned_parm) = TREE_ADDRESSABLE (parm);
121 /* The definition might have different constness. */
122 TREE_READONLY (cloned_parm) = TREE_READONLY (parm);
124 TREE_USED (cloned_parm) = TREE_USED (parm);
126 /* The name may have changed from the declaration. */
127 DECL_NAME (cloned_parm) = DECL_NAME (parm);
128 DECL_SOURCE_LOCATION (cloned_parm) = DECL_SOURCE_LOCATION (parm);
131 /* FN is a function that has a complete body. Clone the body as
132 necessary. Returns nonzero if there's no longer any need to
133 process the main body. */
136 maybe_clone_body (tree fn)
141 /* We only clone constructors and destructors. */
142 if (!DECL_MAYBE_IN_CHARGE_CONSTRUCTOR_P (fn)
143 && !DECL_MAYBE_IN_CHARGE_DESTRUCTOR_P (fn))
146 /* Emit the DWARF1 abstract instance. */
147 (*debug_hooks->deferred_inline_function) (fn);
149 /* We know that any clones immediately follow FN in the TYPE_METHODS
151 for (clone = TREE_CHAIN (fn);
152 clone && DECL_CLONED_FUNCTION_P (clone);
153 clone = TREE_CHAIN (clone), first = false)
160 /* Update CLONE's source position information to match FN's. */
161 DECL_SOURCE_LOCATION (clone) = DECL_SOURCE_LOCATION (fn);
162 DECL_INLINE (clone) = DECL_INLINE (fn);
163 DECL_DECLARED_INLINE_P (clone) = DECL_DECLARED_INLINE_P (fn);
164 DECL_COMDAT (clone) = DECL_COMDAT (fn);
165 DECL_WEAK (clone) = DECL_WEAK (fn);
166 DECL_ONE_ONLY (clone) = DECL_ONE_ONLY (fn);
167 DECL_SECTION_NAME (clone) = DECL_SECTION_NAME (fn);
168 DECL_USE_TEMPLATE (clone) = DECL_USE_TEMPLATE (fn);
169 DECL_EXTERNAL (clone) = DECL_EXTERNAL (fn);
170 DECL_INTERFACE_KNOWN (clone) = DECL_INTERFACE_KNOWN (fn);
171 DECL_NOT_REALLY_EXTERN (clone) = DECL_NOT_REALLY_EXTERN (fn);
172 TREE_PUBLIC (clone) = TREE_PUBLIC (fn);
174 /* Adjust the parameter names and locations. */
175 parm = DECL_ARGUMENTS (fn);
176 clone_parm = DECL_ARGUMENTS (clone);
177 /* Update the `this' parameter, which is always first. */
178 update_cloned_parm (parm, clone_parm);
179 parm = TREE_CHAIN (parm);
180 clone_parm = TREE_CHAIN (clone_parm);
181 if (DECL_HAS_IN_CHARGE_PARM_P (fn))
182 parm = TREE_CHAIN (parm);
183 if (DECL_HAS_VTT_PARM_P (fn))
184 parm = TREE_CHAIN (parm);
185 if (DECL_HAS_VTT_PARM_P (clone))
186 clone_parm = TREE_CHAIN (clone_parm);
188 parm = TREE_CHAIN (parm), clone_parm = TREE_CHAIN (clone_parm))
190 /* Update this parameter. */
191 update_cloned_parm (parm, clone_parm);
192 /* We should only give unused information for one clone. */
194 TREE_USED (clone_parm) = 1;
197 /* Start processing the function. */
198 push_to_top_level ();
199 start_function (NULL_TREE, clone, NULL_TREE, SF_PRE_PARSED);
201 /* Remap the parameters. */
202 decl_map = splay_tree_new (splay_tree_compare_pointers, NULL, NULL);
204 parm = DECL_ARGUMENTS (fn),
205 clone_parm = DECL_ARGUMENTS (clone);
208 parm = TREE_CHAIN (parm))
210 /* Map the in-charge parameter to an appropriate constant. */
211 if (DECL_HAS_IN_CHARGE_PARM_P (fn) && parmno == 1)
214 in_charge = in_charge_arg_for_name (DECL_NAME (clone));
215 splay_tree_insert (decl_map,
216 (splay_tree_key) parm,
217 (splay_tree_value) in_charge);
219 else if (DECL_ARTIFICIAL (parm)
220 && DECL_NAME (parm) == vtt_parm_identifier)
222 /* For a subobject constructor or destructor, the next
223 argument is the VTT parameter. Remap the VTT_PARM
224 from the CLONE to this parameter. */
225 if (DECL_HAS_VTT_PARM_P (clone))
227 DECL_ABSTRACT_ORIGIN (clone_parm) = parm;
228 splay_tree_insert (decl_map,
229 (splay_tree_key) parm,
230 (splay_tree_value) clone_parm);
231 clone_parm = TREE_CHAIN (clone_parm);
233 /* Otherwise, map the VTT parameter to `NULL'. */
236 splay_tree_insert (decl_map,
237 (splay_tree_key) parm,
238 (splay_tree_value) null_pointer_node);
241 /* Map other parameters to their equivalents in the cloned
245 splay_tree_insert (decl_map,
246 (splay_tree_key) parm,
247 (splay_tree_value) clone_parm);
248 clone_parm = TREE_CHAIN (clone_parm);
252 /* Clone the body. */
253 clone_body (clone, fn, decl_map);
255 /* There are as many statements in the clone as in the
257 DECL_NUM_STMTS (clone) = DECL_NUM_STMTS (fn);
260 splay_tree_delete (decl_map);
262 /* Now, expand this function into RTL, if appropriate. */
264 BLOCK_ABSTRACT_ORIGIN (DECL_INITIAL (clone)) = DECL_INITIAL (fn);
266 pop_from_top_level ();
269 /* We don't need to process the original function any further. */
273 /* Dump FUNCTION_DECL FN as tree dump PHASE. */
276 dump_function (enum tree_dump_index phase, tree fn)
281 stream = dump_begin (phase, &flags);
284 fprintf (stream, "\n;; Function %s",
285 decl_as_string (fn, TFF_DECL_SPECIFIERS));
286 fprintf (stream, " (%s)\n",
287 decl_as_string (DECL_ASSEMBLER_NAME (fn), 0));
288 fprintf (stream, ";; enabled by -%s\n", dump_flag_name (phase));
289 fprintf (stream, "\n");
291 dump_node (fn, TDF_SLIM | flags, stream);
292 dump_end (phase, stream);