1 /* Miscellaneous utilities for GIMPLE streaming. Things that are used
2 in both input and output are here.
3
4 Copyright (C) 2009-2013 Free Software Foundation, Inc.
5 Contributed by Doug Kwan <dougkwan@google.com>
6
7 This file is part of GCC.
8
9 GCC is free software; you can redistribute it and/or modify it under
10 the terms of the GNU General Public License as published by the Free
11 Software Foundation; either version 3, or (at your option) any later
12 version.
13
14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
16 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 for more details.
18
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING3. If not see
21 <http://www.gnu.org/licenses/>. */
22
23 #include "config.h"
24 #include "system.h"
25 #include "coretypes.h"
26 #include "tm.h"
27 #include "toplev.h"
28 #include "flags.h"
29 #include "tree.h"
30 #include "gimple.h"
31 #include "tree-flow.h"
32 #include "diagnostic-core.h"
33 #include "bitmap.h"
34 #include "vec.h"
35 #include "tree-streamer.h"
36 #include "lto-streamer.h"
37 #include "streamer-hooks.h"
38
39 /* Statistics gathered during LTO, WPA and LTRANS. */
40 struct lto_stats_d lto_stats;
41
42 /* LTO uses bitmaps with different life-times. So use a separate
43 obstack for all LTO bitmaps. */
44 static bitmap_obstack lto_obstack;
45 static bool lto_obstack_initialized;
46
47
48 /* Return a string representing LTO tag TAG. */
49
50 const char *
lto_tag_name(enum LTO_tags tag)51 lto_tag_name (enum LTO_tags tag)
52 {
53 if (lto_tag_is_tree_code_p (tag))
54 {
55 /* For tags representing tree nodes, return the name of the
56 associated tree code. */
57 return tree_code_name[lto_tag_to_tree_code (tag)];
58 }
59
60 if (lto_tag_is_gimple_code_p (tag))
61 {
62 /* For tags representing gimple statements, return the name of
63 the associated gimple code. */
64 return gimple_code_name[lto_tag_to_gimple_code (tag)];
65 }
66
67 switch (tag)
68 {
69 case LTO_null:
70 return "LTO_null";
71 case LTO_bb0:
72 return "LTO_bb0";
73 case LTO_bb1:
74 return "LTO_bb1";
75 case LTO_eh_region:
76 return "LTO_eh_region";
77 case LTO_function:
78 return "LTO_function";
79 case LTO_eh_table:
80 return "LTO_eh_table";
81 case LTO_ert_cleanup:
82 return "LTO_ert_cleanup";
83 case LTO_ert_try:
84 return "LTO_ert_try";
85 case LTO_ert_allowed_exceptions:
86 return "LTO_ert_allowed_exceptions";
87 case LTO_ert_must_not_throw:
88 return "LTO_ert_must_not_throw";
89 case LTO_tree_pickle_reference:
90 return "LTO_tree_pickle_reference";
91 case LTO_field_decl_ref:
92 return "LTO_field_decl_ref";
93 case LTO_function_decl_ref:
94 return "LTO_function_decl_ref";
95 case LTO_label_decl_ref:
96 return "LTO_label_decl_ref";
97 case LTO_namespace_decl_ref:
98 return "LTO_namespace_decl_ref";
99 case LTO_result_decl_ref:
100 return "LTO_result_decl_ref";
101 case LTO_ssa_name_ref:
102 return "LTO_ssa_name_ref";
103 case LTO_type_decl_ref:
104 return "LTO_type_decl_ref";
105 case LTO_type_ref:
106 return "LTO_type_ref";
107 case LTO_global_decl_ref:
108 return "LTO_global_decl_ref";
109 default:
110 return "LTO_UNKNOWN";
111 }
112 }
113
114
115 /* Allocate a bitmap from heap. Initializes the LTO obstack if necessary. */
116
117 bitmap
lto_bitmap_alloc(void)118 lto_bitmap_alloc (void)
119 {
120 if (!lto_obstack_initialized)
121 {
122 bitmap_obstack_initialize (<o_obstack);
123 lto_obstack_initialized = true;
124 }
125 return BITMAP_ALLOC (<o_obstack);
126 }
127
128 /* Free bitmap B. */
129
130 void
lto_bitmap_free(bitmap b)131 lto_bitmap_free (bitmap b)
132 {
133 BITMAP_FREE (b);
134 }
135
136
137 /* Get a section name for a particular type or name. The NAME field
138 is only used if SECTION_TYPE is LTO_section_function_body. For all
139 others it is ignored. The callee of this function is responsible
140 to free the returned name. */
141
142 char *
lto_get_section_name(int section_type,const char * name,struct lto_file_decl_data * f)143 lto_get_section_name (int section_type, const char *name, struct lto_file_decl_data *f)
144 {
145 const char *add;
146 char post[32];
147 const char *sep;
148
149 if (section_type == LTO_section_function_body)
150 {
151 gcc_assert (name != NULL);
152 if (name[0] == '*')
153 name++;
154 add = name;
155 sep = "";
156 }
157 else if (section_type < LTO_N_SECTION_TYPES)
158 {
159 add = lto_section_name[section_type];
160 sep = ".";
161 }
162 else
163 internal_error ("bytecode stream: unexpected LTO section %s", name);
164
165 /* Make the section name unique so that ld -r combining sections
166 doesn't confuse the reader with merged sections.
167
168 For options don't add a ID, the option reader cannot deal with them
169 and merging should be ok here. */
170 if (section_type == LTO_section_opts)
171 strcpy (post, "");
172 else if (f != NULL)
173 sprintf (post, "." HOST_WIDE_INT_PRINT_HEX_PURE, f->id);
174 else
175 sprintf (post, "." HOST_WIDE_INT_PRINT_HEX_PURE, get_random_seed (false));
176 return concat (LTO_SECTION_NAME_PREFIX, sep, add, post, NULL);
177 }
178
179
180 /* Show various memory usage statistics related to LTO. */
181
182 void
print_lto_report(const char * s)183 print_lto_report (const char *s)
184 {
185 unsigned i;
186
187 fprintf (stderr, "[%s] # of input files: "
188 HOST_WIDE_INT_PRINT_UNSIGNED "\n", s, lto_stats.num_input_files);
189
190 fprintf (stderr, "[%s] # of input cgraph nodes: "
191 HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
192 lto_stats.num_input_cgraph_nodes);
193
194 fprintf (stderr, "[%s] # of function bodies: "
195 HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
196 lto_stats.num_function_bodies);
197
198 for (i = 0; i < NUM_TREE_CODES; i++)
199 if (lto_stats.num_trees[i])
200 fprintf (stderr, "[%s] # of '%s' objects read: "
201 HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
202 tree_code_name[i], lto_stats.num_trees[i]);
203
204 if (flag_lto)
205 {
206 fprintf (stderr, "[%s] Compression: "
207 HOST_WIDE_INT_PRINT_UNSIGNED " output bytes, "
208 HOST_WIDE_INT_PRINT_UNSIGNED " compressed bytes", s,
209 lto_stats.num_output_il_bytes,
210 lto_stats.num_compressed_il_bytes);
211 if (lto_stats.num_output_il_bytes > 0)
212 {
213 const float dividend = (float) lto_stats.num_compressed_il_bytes;
214 const float divisor = (float) lto_stats.num_output_il_bytes;
215 fprintf (stderr, " (ratio: %f)", dividend / divisor);
216 }
217 fprintf (stderr, "\n");
218 }
219
220 if (flag_wpa)
221 {
222 fprintf (stderr, "[%s] # of output files: "
223 HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
224 lto_stats.num_output_files);
225
226 fprintf (stderr, "[%s] # of output symtab nodes: "
227 HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
228 lto_stats.num_output_symtab_nodes);
229
230 fprintf (stderr, "[%s] # callgraph partitions: "
231 HOST_WIDE_INT_PRINT_UNSIGNED "\n", s,
232 lto_stats.num_cgraph_partitions);
233
234 fprintf (stderr, "[%s] Compression: "
235 HOST_WIDE_INT_PRINT_UNSIGNED " input bytes, "
236 HOST_WIDE_INT_PRINT_UNSIGNED " uncompressed bytes", s,
237 lto_stats.num_input_il_bytes,
238 lto_stats.num_uncompressed_il_bytes);
239 if (lto_stats.num_input_il_bytes > 0)
240 {
241 const float dividend = (float) lto_stats.num_uncompressed_il_bytes;
242 const float divisor = (float) lto_stats.num_input_il_bytes;
243 fprintf (stderr, " (ratio: %f)", dividend / divisor);
244 }
245 fprintf (stderr, "\n");
246 }
247
248 for (i = 0; i < LTO_N_SECTION_TYPES; i++)
249 fprintf (stderr, "[%s] Size of mmap'd section %s: "
250 HOST_WIDE_INT_PRINT_UNSIGNED " bytes\n", s,
251 lto_section_name[i], lto_stats.section_size[i]);
252 }
253
254
255 #ifdef LTO_STREAMER_DEBUG
256 static htab_t tree_htab;
257
258 struct tree_hash_entry
259 {
260 tree key;
261 intptr_t value;
262 };
263
264 static hashval_t
hash_tree(const void * p)265 hash_tree (const void *p)
266 {
267 const struct tree_hash_entry *e = (const struct tree_hash_entry *) p;
268 return htab_hash_pointer (e->key);
269 }
270
271 static int
eq_tree(const void * p1,const void * p2)272 eq_tree (const void *p1, const void *p2)
273 {
274 const struct tree_hash_entry *e1 = (const struct tree_hash_entry *) p1;
275 const struct tree_hash_entry *e2 = (const struct tree_hash_entry *) p2;
276 return (e1->key == e2->key);
277 }
278 #endif
279
280 /* Initialization common to the LTO reader and writer. */
281
282 void
lto_streamer_init(void)283 lto_streamer_init (void)
284 {
285 /* Check that all the TS_* handled by the reader and writer routines
286 match exactly the structures defined in treestruct.def. When a
287 new TS_* astructure is added, the streamer should be updated to
288 handle it. */
289 streamer_check_handled_ts_structures ();
290
291 #ifdef LTO_STREAMER_DEBUG
292 tree_htab = htab_create (31, hash_tree, eq_tree, NULL);
293 #endif
294 }
295
296
297 /* Gate function for all LTO streaming passes. */
298
299 bool
gate_lto_out(void)300 gate_lto_out (void)
301 {
302 return ((flag_generate_lto || in_lto_p)
303 /* Don't bother doing anything if the program has errors. */
304 && !seen_error ());
305 }
306
307
308 #ifdef LTO_STREAMER_DEBUG
309 /* Add a mapping between T and ORIG_T, which is the numeric value of
310 the original address of T as it was seen by the LTO writer. This
311 mapping is useful when debugging streaming problems. A debugging
312 session can be started on both reader and writer using ORIG_T
313 as a breakpoint value in both sessions.
314
315 Note that this mapping is transient and only valid while T is
316 being reconstructed. Once T is fully built, the mapping is
317 removed. */
318
319 void
lto_orig_address_map(tree t,intptr_t orig_t)320 lto_orig_address_map (tree t, intptr_t orig_t)
321 {
322 struct tree_hash_entry ent;
323 struct tree_hash_entry **slot;
324
325 ent.key = t;
326 ent.value = orig_t;
327 slot
328 = (struct tree_hash_entry **) htab_find_slot (tree_htab, &ent, INSERT);
329 gcc_assert (!*slot);
330 *slot = XNEW (struct tree_hash_entry);
331 **slot = ent;
332 }
333
334
335 /* Get the original address of T as it was seen by the writer. This
336 is only valid while T is being reconstructed. */
337
338 intptr_t
lto_orig_address_get(tree t)339 lto_orig_address_get (tree t)
340 {
341 struct tree_hash_entry ent;
342 struct tree_hash_entry **slot;
343
344 ent.key = t;
345 slot
346 = (struct tree_hash_entry **) htab_find_slot (tree_htab, &ent, NO_INSERT);
347 return (slot ? (*slot)->value : 0);
348 }
349
350
351 /* Clear the mapping of T to its original address. */
352
353 void
lto_orig_address_remove(tree t)354 lto_orig_address_remove (tree t)
355 {
356 struct tree_hash_entry ent;
357 struct tree_hash_entry **slot;
358
359 ent.key = t;
360 slot
361 = (struct tree_hash_entry **) htab_find_slot (tree_htab, &ent, NO_INSERT);
362 gcc_assert (slot);
363 free (*slot);
364 htab_clear_slot (tree_htab, (PTR *)slot);
365 }
366 #endif
367
368
369 /* Check that the version MAJOR.MINOR is the correct version number. */
370
371 void
lto_check_version(int major,int minor)372 lto_check_version (int major, int minor)
373 {
374 if (major != LTO_major_version || minor != LTO_minor_version)
375 fatal_error ("bytecode stream generated with LTO version %d.%d instead "
376 "of the expected %d.%d",
377 major, minor,
378 LTO_major_version, LTO_minor_version);
379 }
380
381
382 /* Initialize all the streamer hooks used for streaming GIMPLE. */
383
384 void
lto_streamer_hooks_init(void)385 lto_streamer_hooks_init (void)
386 {
387 streamer_hooks_init ();
388 streamer_hooks.write_tree = lto_output_tree;
389 streamer_hooks.read_tree = lto_input_tree;
390 streamer_hooks.input_location = lto_input_location;
391 streamer_hooks.output_location = lto_output_location;
392 }
393