1/* Functions for writing LTO sections.
2
3 Copyright (C) 2009-2017 Free Software Foundation, Inc.
4 Contributed by Kenneth Zadeck <zadeck@naturalbridge.com>
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along with GCC; see the file COPYING3. If not see
20<http://www.gnu.org/licenses/>. */
21
22#include "config.h"
23#include "system.h"
24#include "coretypes.h"
25#include "backend.h"
26#include "rtl.h"
27#include "tree.h"
28#include "gimple.h"
29#include "cgraph.h"
30#include "data-streamer.h"
31#include "langhooks.h"
32#include "lto-compress.h"
33
34static vec<lto_out_decl_state_ptr> decl_state_stack;
35
36/* List of out decl states used by functions. We use this to
37 generate the decl directory later. */
38
39vec<lto_out_decl_state_ptr> lto_function_decl_states;
40
41
42/*****************************************************************************
43 Output routines shared by all of the serialization passes.
44*****************************************************************************/
45
46
47/* Flush compressed stream data function, sends NUM_CHARS from CHARS
48 to the append lang hook, OPAQUE is currently always NULL. */
49
50static void
51lto_append_data (const char *chars, unsigned int num_chars, void *opaque)
52{
53 gcc_assert (opaque == NULL);
54 lang_hooks.lto.append_data (chars, num_chars, opaque);
55}
56
57/* Pointer to the current compression stream. */
58
59static struct lto_compression_stream *compression_stream = NULL;
60
61/* Begin a new output section named NAME. If COMPRESS is true, zlib compress
62 the section. */
63
64void
65lto_begin_section (const char *name, bool compress)
66{
67 lang_hooks.lto.begin_section (name);
68
69 gcc_assert (compression_stream == NULL);
70 if (compress)
71 compression_stream = lto_start_compression (lto_append_data, NULL);
72}
73
74
75/* End the current output section. */
76
77void
78lto_end_section (void)
79{
80 if (compression_stream)
81 {
82 lto_end_compression (compression_stream);
83 compression_stream = NULL;
84 }
85 lang_hooks.lto.end_section ();
86}
87
88/* Write SIZE bytes starting at DATA to the assembler. */
89
90void
91lto_write_data (const void *data, unsigned int size)
92{
93 if (compression_stream)
94 lto_compress_block (compression_stream, (const char *)data, size);
95 else
96 lang_hooks.lto.append_data ((const char *)data, size, NULL);
97}
98
99/* Write SIZE bytes starting at DATA to the assembler. */
100
101void
102lto_write_raw_data (const void *data, unsigned int size)
103{
104 lang_hooks.lto.append_data ((const char *)data, size, NULL);
105}
106
107/* Write all of the chars in OBS to the assembler. Recycle the blocks
108 in obs as this is being done. */
109
110void
111lto_write_stream (struct lto_output_stream *obs)
112{
113 unsigned int block_size = 1024;
114 struct lto_char_ptr_base *block;
115 struct lto_char_ptr_base *next_block;
116 if (!obs->first_block)
117 return;
118
119 for (block = obs->first_block; block; block = next_block)
120 {
121 const char *base = ((char *)block) + sizeof (struct lto_char_ptr_base);
122 unsigned int num_chars = block_size - sizeof (struct lto_char_ptr_base);
123
124 /* If this is not the last block, it is full. If it is the last
125 block, left_in_block indicates how many chars are unoccupied in
126 this block; subtract from num_chars to obtain occupancy. */
127 next_block = (struct lto_char_ptr_base *) block->ptr;
128 if (!next_block)
129 num_chars -= obs->left_in_block;
130
131 if (compression_stream)
132 lto_compress_block (compression_stream, base, num_chars);
133 else
134 lang_hooks.lto.append_data (base, num_chars, block);
135 free (block);
136 block_size *= 2;
137 }
138}
139
140
141/* Lookup NAME in ENCODER. If NAME is not found, create a new entry in
142 ENCODER for NAME with the next available index of ENCODER, then
143 print the index to OBS. True is returned if NAME was added to
144 ENCODER. The resulting index is stored in THIS_INDEX.
145
146 If OBS is NULL, the only action is to add NAME to the encoder. */
147
148bool
149lto_output_decl_index (struct lto_output_stream *obs,
150 struct lto_tree_ref_encoder *encoder,
151 tree name, unsigned int *this_index)
152{
153 bool new_entry_p = FALSE;
154 bool existed_p;
155
156 unsigned int &index
157 = encoder->tree_hash_table->get_or_insert (name, &existed_p);
158 if (!existed_p)
159 {
160 index = encoder->trees.length ();
161 encoder->trees.safe_push (name);
162 new_entry_p = TRUE;
163 }
164
165 if (obs)
166 streamer_write_uhwi_stream (obs, index);
167 *this_index = index;
168 return new_entry_p;
169}
170
171/* Output a field DECL to OBS. */
172
173void
174lto_output_field_decl_index (struct lto_out_decl_state *decl_state,
175 struct lto_output_stream * obs, tree decl)
176{
177 unsigned int index;
178 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_FIELD_DECL],
179 decl, &index);
180}
181
182/* Output a function DECL to OBS. */
183
184void
185lto_output_fn_decl_index (struct lto_out_decl_state *decl_state,
186 struct lto_output_stream * obs, tree decl)
187{
188 unsigned int index;
189 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_FN_DECL],
190 decl, &index);
191}
192
193/* Output a namespace DECL to OBS. */
194
195void
196lto_output_namespace_decl_index (struct lto_out_decl_state *decl_state,
197 struct lto_output_stream * obs, tree decl)
198{
199 unsigned int index;
200 lto_output_decl_index (obs,
201 &decl_state->streams[LTO_DECL_STREAM_NAMESPACE_DECL],
202 decl, &index);
203}
204
205/* Output a static or extern var DECL to OBS. */
206
207void
208lto_output_var_decl_index (struct lto_out_decl_state *decl_state,
209 struct lto_output_stream * obs, tree decl)
210{
211 unsigned int index;
212 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_VAR_DECL],
213 decl, &index);
214}
215
216/* Output a type DECL to OBS. */
217
218void
219lto_output_type_decl_index (struct lto_out_decl_state *decl_state,
220 struct lto_output_stream * obs, tree decl)
221{
222 unsigned int index;
223 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_TYPE_DECL],
224 decl, &index);
225}
226
227/* Output a type REF to OBS. */
228
229void
230lto_output_type_ref_index (struct lto_out_decl_state *decl_state,
231 struct lto_output_stream *obs, tree ref)
232{
233 unsigned int index;
234 lto_output_decl_index (obs, &decl_state->streams[LTO_DECL_STREAM_TYPE],
235 ref, &index);
236}
237
238
239/* Create the output block and return it. */
240
241struct lto_simple_output_block *
242lto_create_simple_output_block (enum lto_section_type section_type)
243{
244 struct lto_simple_output_block *ob
245 = ((struct lto_simple_output_block *)
246 xcalloc (1, sizeof (struct lto_simple_output_block)));
247
248 ob->section_type = section_type;
249 ob->decl_state = lto_get_out_decl_state ();
250 ob->main_stream = ((struct lto_output_stream *)
251 xcalloc (1, sizeof (struct lto_output_stream)));
252
253 return ob;
254}
255
256
257/* Produce a simple section for one of the ipa passes. */
258
259void
260lto_destroy_simple_output_block (struct lto_simple_output_block *ob)
261{
262 char *section_name;
263 struct lto_simple_header header;
264
265 section_name = lto_get_section_name (ob->section_type, NULL, NULL);
266 lto_begin_section (section_name, !flag_wpa);
267 free (section_name);
268
269 /* Write the header which says how to decode the pieces of the
270 t. */
271 memset (&header, 0, sizeof (struct lto_simple_header));
272 header.major_version = LTO_major_version;
273 header.minor_version = LTO_minor_version;
274 header.main_size = ob->main_stream->total_size;
275 lto_write_data (&header, sizeof header);
276
277 lto_write_stream (ob->main_stream);
278
279 /* Put back the assembly section that was there before we started
280 writing lto info. */
281 lto_end_section ();
282
283 free (ob->main_stream);
284 free (ob);
285}
286
287
288/* Return a new lto_out_decl_state. */
289
290struct lto_out_decl_state *
291lto_new_out_decl_state (void)
292{
293 struct lto_out_decl_state *state = XCNEW (struct lto_out_decl_state);
294 int i;
295
296 for (i = 0; i < LTO_N_DECL_STREAMS; i++)
297 lto_init_tree_ref_encoder (&state->streams[i]);
298
299 /* At WPA time we do not compress sections by default. */
300 state->compressed = !flag_wpa;
301
302 return state;
303}
304
305
306/* Delete STATE and components. */
307
308void
309lto_delete_out_decl_state (struct lto_out_decl_state *state)
310{
311 int i;
312
313 for (i = 0; i < LTO_N_DECL_STREAMS; i++)
314 lto_destroy_tree_ref_encoder (&state->streams[i]);
315
316 free (state);
317}
318
319
320/* Get the currently used lto_out_decl_state structure. */
321
322struct lto_out_decl_state *
323lto_get_out_decl_state (void)
324{
325 return decl_state_stack.last ();
326}
327
328/* Push STATE to top of out decl stack. */
329
330void
331lto_push_out_decl_state (struct lto_out_decl_state *state)
332{
333 decl_state_stack.safe_push (state);
334}
335
336/* Pop the currently used out-decl state from top of stack. */
337
338struct lto_out_decl_state *
339lto_pop_out_decl_state (void)
340{
341 return decl_state_stack.pop ();
342}
343
344/* Record STATE after it has been used in serializing the body of
345 FN_DECL. STATE should no longer be used by the caller. The ownership
346 of it is taken over from this point. */
347
348void
349lto_record_function_out_decl_state (tree fn_decl,
350 struct lto_out_decl_state *state)
351{
352 int i;
353
354 /* Strip all hash tables to save some memory. */
355 for (i = 0; i < LTO_N_DECL_STREAMS; i++)
356 if (state->streams[i].tree_hash_table)
357 {
358 delete state->streams[i].tree_hash_table;
359 state->streams[i].tree_hash_table = NULL;
360 }
361 state->fn_decl = fn_decl;
362 lto_function_decl_states.safe_push (state);
363}
364