2011-10-08 Paul Thomas <pault@gcc.gnu.org>
[official-gcc.git] / gcc / lto-section-out.c
blobfe3cc54c7f96b2cd2667674e971de098aac1e220
1 /* Functions for writing LTO sections.
3 Copyright (C) 2009, 2010 Free Software Foundation, Inc.
4 Contributed by Kenneth Zadeck <zadeck@naturalbridge.com>
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "tree.h"
27 #include "expr.h"
28 #include "params.h"
29 #include "input.h"
30 #include "hashtab.h"
31 #include "basic-block.h"
32 #include "tree-flow.h"
33 #include "tree-pass.h"
34 #include "cgraph.h"
35 #include "function.h"
36 #include "ggc.h"
37 #include "except.h"
38 #include "vec.h"
39 #include "pointer-set.h"
40 #include "bitmap.h"
41 #include "langhooks.h"
42 #include "data-streamer.h"
43 #include "lto-streamer.h"
44 #include "lto-compress.h"
46 static VEC(lto_out_decl_state_ptr, heap) *decl_state_stack;
48 /* List of out decl states used by functions. We use this to
49 generate the decl directory later. */
51 VEC(lto_out_decl_state_ptr, heap) *lto_function_decl_states;
52 /* Returns a hash code for P. */
54 hashval_t
55 lto_hash_decl_slot_node (const void *p)
57 const struct lto_decl_slot *ds = (const struct lto_decl_slot *) p;
60 return (hashval_t) DECL_UID (ds->t);
62 return (hashval_t) TREE_HASH (ds->t);
66 /* Returns nonzero if P1 and P2 are equal. */
68 int
69 lto_eq_decl_slot_node (const void *p1, const void *p2)
71 const struct lto_decl_slot *ds1 =
72 (const struct lto_decl_slot *) p1;
73 const struct lto_decl_slot *ds2 =
74 (const struct lto_decl_slot *) p2;
77 return DECL_UID (ds1->t) == DECL_UID (ds2->t);
79 return ds1->t == ds2->t;
83 /* Returns a hash code for P. */
85 hashval_t
86 lto_hash_type_slot_node (const void *p)
88 const struct lto_decl_slot *ds = (const struct lto_decl_slot *) p;
89 return (hashval_t) TYPE_UID (ds->t);
93 /* Returns nonzero if P1 and P2 are equal. */
95 int
96 lto_eq_type_slot_node (const void *p1, const void *p2)
98 const struct lto_decl_slot *ds1 =
99 (const struct lto_decl_slot *) p1;
100 const struct lto_decl_slot *ds2 =
101 (const struct lto_decl_slot *) p2;
103 return TYPE_UID (ds1->t) == TYPE_UID (ds2->t);
106 /*****************************************************************************
107 Output routines shared by all of the serialization passes.
108 *****************************************************************************/
111 /* Flush compressed stream data function, sends NUM_CHARS from CHARS
112 to the append lang hook, OPAQUE is currently always NULL. */
114 static void
115 lto_append_data (const char *chars, unsigned int num_chars, void *opaque)
117 gcc_assert (opaque == NULL);
118 lang_hooks.lto.append_data (chars, num_chars, opaque);
121 /* Pointer to the current compression stream. */
123 static struct lto_compression_stream *compression_stream = NULL;
125 /* Begin a new output section named NAME. If COMPRESS is true, zlib compress
126 the section. */
128 void
129 lto_begin_section (const char *name, bool compress)
131 lang_hooks.lto.begin_section (name);
133 /* FIXME lto: for now, suppress compression if the lang_hook that appends
134 data is anything other than assembler output. The effect here is that
135 we get compression of IL only in non-ltrans object files. */
136 gcc_assert (compression_stream == NULL);
137 if (compress)
138 compression_stream = lto_start_compression (lto_append_data, NULL);
142 /* End the current output section. */
144 void
145 lto_end_section (void)
147 if (compression_stream)
149 lto_end_compression (compression_stream);
150 compression_stream = NULL;
152 lang_hooks.lto.end_section ();
156 /* Write all of the chars in OBS to the assembler. Recycle the blocks
157 in obs as this is being done. */
159 void
160 lto_write_stream (struct lto_output_stream *obs)
162 unsigned int block_size = 1024;
163 struct lto_char_ptr_base *block;
164 struct lto_char_ptr_base *next_block;
165 if (!obs->first_block)
166 return;
168 for (block = obs->first_block; block; block = next_block)
170 const char *base = ((char *)block) + sizeof (struct lto_char_ptr_base);
171 unsigned int num_chars = block_size - sizeof (struct lto_char_ptr_base);
173 /* If this is not the last block, it is full. If it is the last
174 block, left_in_block indicates how many chars are unoccupied in
175 this block; subtract from num_chars to obtain occupancy. */
176 next_block = (struct lto_char_ptr_base *) block->ptr;
177 if (!next_block)
178 num_chars -= obs->left_in_block;
180 /* FIXME lto: WPA mode uses an ELF function as a lang_hook to append
181 output data. This hook is not happy with the way that compression
182 blocks up output differently to the way it's blocked here. So for
183 now, we don't compress WPA output. */
184 if (compression_stream)
186 lto_compress_block (compression_stream, base, num_chars);
187 lang_hooks.lto.append_data (NULL, 0, block);
189 else
190 lang_hooks.lto.append_data (base, num_chars, block);
191 block_size *= 2;
196 /* Adds a new block to output stream OBS. */
198 void
199 lto_append_block (struct lto_output_stream *obs)
201 struct lto_char_ptr_base *new_block;
203 gcc_assert (obs->left_in_block == 0);
205 if (obs->first_block == NULL)
207 /* This is the first time the stream has been written
208 into. */
209 obs->block_size = 1024;
210 new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
211 obs->first_block = new_block;
213 else
215 struct lto_char_ptr_base *tptr;
216 /* Get a new block that is twice as big as the last block
217 and link it into the list. */
218 obs->block_size *= 2;
219 new_block = (struct lto_char_ptr_base*) xmalloc (obs->block_size);
220 /* The first bytes of the block are reserved as a pointer to
221 the next block. Set the chain of the full block to the
222 pointer to the new block. */
223 tptr = obs->current_block;
224 tptr->ptr = (char *) new_block;
227 /* Set the place for the next char at the first position after the
228 chain to the next block. */
229 obs->current_pointer
230 = ((char *) new_block) + sizeof (struct lto_char_ptr_base);
231 obs->current_block = new_block;
232 /* Null out the newly allocated block's pointer to the next block. */
233 new_block->ptr = NULL;
234 obs->left_in_block = obs->block_size - sizeof (struct lto_char_ptr_base);
238 /* Write raw DATA of length LEN to the output block OB. */
240 void
241 lto_output_data_stream (struct lto_output_stream *obs, const void *data,
242 size_t len)
244 while (len)
246 size_t copy;
248 /* No space left. */
249 if (obs->left_in_block == 0)
250 lto_append_block (obs);
252 /* Determine how many bytes to copy in this loop. */
253 if (len <= obs->left_in_block)
254 copy = len;
255 else
256 copy = obs->left_in_block;
258 /* Copy the data and do bookkeeping. */
259 memcpy (obs->current_pointer, data, copy);
260 obs->current_pointer += copy;
261 obs->total_size += copy;
262 obs->left_in_block -= copy;
263 data = (const char *) data + copy;
264 len -= copy;
269 /* Lookup NAME in ENCODER. If NAME is not found, create a new entry in
270 ENCODER for NAME with the next available index of ENCODER, then
271 print the index to OBS. True is returned if NAME was added to
272 ENCODER. The resulting index is stored in THIS_INDEX.
274 If OBS is NULL, the only action is to add NAME to the encoder. */
276 bool
277 lto_output_decl_index (struct lto_output_stream *obs,
278 struct lto_tree_ref_encoder *encoder,
279 tree name, unsigned int *this_index)
281 void **slot;
282 struct lto_decl_slot d_slot;
283 int index;
284 bool new_entry_p = FALSE;
286 d_slot.t = name;
287 slot = htab_find_slot (encoder->tree_hash_table, &d_slot, INSERT);
288 if (*slot == NULL)
290 struct lto_decl_slot *new_slot
291 = (struct lto_decl_slot *) xmalloc (sizeof (struct lto_decl_slot));
292 index = encoder->next_index++;
294 new_slot->t = name;
295 new_slot->slot_num = index;
296 *slot = new_slot;
297 VEC_safe_push (tree, heap, encoder->trees, name);
298 new_entry_p = TRUE;
300 else
302 struct lto_decl_slot *old_slot = (struct lto_decl_slot *)*slot;
303 index = old_slot->slot_num;
306 if (obs)
307 streamer_write_uhwi_stream (obs, index);
308 *this_index = index;
309 return new_entry_p;
312 /* Output a field DECL to OBS. */
314 void
315 lto_output_field_decl_index (struct lto_out_decl_state *decl_state,
316 struct lto_output_stream * obs, tree decl)
318 unsigned int index;
319 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_FIELD_DECL],
320 decl, &index);
323 /* Output a function DECL to OBS. */
325 void
326 lto_output_fn_decl_index (struct lto_out_decl_state *decl_state,
327 struct lto_output_stream * obs, tree decl)
329 unsigned int index;
330 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_FN_DECL],
331 decl, &index);
334 /* Output a namespace DECL to OBS. */
336 void
337 lto_output_namespace_decl_index (struct lto_out_decl_state *decl_state,
338 struct lto_output_stream * obs, tree decl)
340 unsigned int index;
341 lto_output_decl_index (obs,
342 &decl_state->streams[LTO_DECL_STREAM_NAMESPACE_DECL],
343 decl, &index);
346 /* Output a static or extern var DECL to OBS. */
348 void
349 lto_output_var_decl_index (struct lto_out_decl_state *decl_state,
350 struct lto_output_stream * obs, tree decl)
352 unsigned int index;
353 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_VAR_DECL],
354 decl, &index);
357 /* Output a type DECL to OBS. */
359 void
360 lto_output_type_decl_index (struct lto_out_decl_state *decl_state,
361 struct lto_output_stream * obs, tree decl)
363 unsigned int index;
364 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_TYPE_DECL],
365 decl, &index);
368 /* Output a type REF to OBS. */
370 void
371 lto_output_type_ref_index (struct lto_out_decl_state *decl_state,
372 struct lto_output_stream *obs, tree ref)
374 unsigned int index;
375 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_TYPE],
376 ref, &index);
380 /* Create the output block and return it. */
382 struct lto_simple_output_block *
383 lto_create_simple_output_block (enum lto_section_type section_type)
385 struct lto_simple_output_block *ob
386 = ((struct lto_simple_output_block *)
387 xcalloc (1, sizeof (struct lto_simple_output_block)));
389 ob->section_type = section_type;
390 ob->decl_state = lto_get_out_decl_state ();
391 ob->main_stream = ((struct lto_output_stream *)
392 xcalloc (1, sizeof (struct lto_output_stream)));
394 return ob;
398 /* Produce a simple section for one of the ipa passes. */
400 void
401 lto_destroy_simple_output_block (struct lto_simple_output_block *ob)
403 char *section_name;
404 struct lto_simple_header header;
405 struct lto_output_stream *header_stream;
407 section_name = lto_get_section_name (ob->section_type, NULL, NULL);
408 lto_begin_section (section_name, !flag_wpa);
409 free (section_name);
411 /* Write the header which says how to decode the pieces of the
412 t. */
413 memset (&header, 0, sizeof (struct lto_simple_header));
414 header.lto_header.major_version = LTO_major_version;
415 header.lto_header.minor_version = LTO_minor_version;
416 header.lto_header.section_type = LTO_section_cgraph;
418 header.compressed_size = 0;
420 header.main_size = ob->main_stream->total_size;
422 header_stream = XCNEW (struct lto_output_stream);
423 lto_output_data_stream (header_stream, &header, sizeof header);
424 lto_write_stream (header_stream);
425 free (header_stream);
427 lto_write_stream (ob->main_stream);
429 /* Put back the assembly section that was there before we started
430 writing lto info. */
431 lto_end_section ();
433 free (ob->main_stream);
434 free (ob);
438 /* Return a new lto_out_decl_state. */
440 struct lto_out_decl_state *
441 lto_new_out_decl_state (void)
443 struct lto_out_decl_state *state = XCNEW (struct lto_out_decl_state);
444 int i;
445 htab_hash hash_fn;
446 htab_eq eq_fn;
448 for (i = 0; i < LTO_N_DECL_STREAMS; i++)
450 if (i == LTO_DECL_STREAM_TYPE)
452 hash_fn = lto_hash_type_slot_node;
453 eq_fn = lto_eq_type_slot_node;
455 else
457 hash_fn = lto_hash_decl_slot_node;
458 eq_fn = lto_eq_decl_slot_node;
460 lto_init_tree_ref_encoder (&state->streams[i], hash_fn, eq_fn);
463 return state;
467 /* Delete STATE and components. */
469 void
470 lto_delete_out_decl_state (struct lto_out_decl_state *state)
472 int i;
474 for (i = 0; i < LTO_N_DECL_STREAMS; i++)
475 lto_destroy_tree_ref_encoder (&state->streams[i]);
477 free (state);
481 /* Get the currently used lto_out_decl_state structure. */
483 struct lto_out_decl_state *
484 lto_get_out_decl_state (void)
486 return VEC_last (lto_out_decl_state_ptr, decl_state_stack);
489 /* Push STATE to top of out decl stack. */
491 void
492 lto_push_out_decl_state (struct lto_out_decl_state *state)
494 VEC_safe_push (lto_out_decl_state_ptr, heap, decl_state_stack, state);
497 /* Pop the currently used out-decl state from top of stack. */
499 struct lto_out_decl_state *
500 lto_pop_out_decl_state (void)
502 return VEC_pop (lto_out_decl_state_ptr, decl_state_stack);
505 /* Record STATE after it has been used in serializing the body of
506 FN_DECL. STATE should no longer be used by the caller. The ownership
507 of it is taken over from this point. */
509 void
510 lto_record_function_out_decl_state (tree fn_decl,
511 struct lto_out_decl_state *state)
513 int i;
515 /* Strip all hash tables to save some memory. */
516 for (i = 0; i < LTO_N_DECL_STREAMS; i++)
517 if (state->streams[i].tree_hash_table)
519 htab_delete (state->streams[i].tree_hash_table);
520 state->streams[i].tree_hash_table = NULL;
522 state->fn_decl = fn_decl;
523 VEC_safe_push (lto_out_decl_state_ptr, heap, lto_function_decl_states,
524 state);