1 /* Functions for writing LTO sections.
3 Copyright (C) 2009-2013 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
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
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/>. */
24 #include "coretypes.h"
32 #include "basic-block.h"
37 #include "pointer-set.h"
38 #include "langhooks.h"
39 #include "data-streamer.h"
40 #include "lto-streamer.h"
41 #include "lto-compress.h"
43 static vec
<lto_out_decl_state_ptr
> decl_state_stack
;
45 /* List of out decl states used by functions. We use this to
46 generate the decl directory later. */
48 vec
<lto_out_decl_state_ptr
> lto_function_decl_states
;
51 /*****************************************************************************
52 Output routines shared by all of the serialization passes.
53 *****************************************************************************/
56 /* Flush compressed stream data function, sends NUM_CHARS from CHARS
57 to the append lang hook, OPAQUE is currently always NULL. */
60 lto_append_data (const char *chars
, unsigned int num_chars
, void *opaque
)
62 gcc_assert (opaque
== NULL
);
63 lang_hooks
.lto
.append_data (chars
, num_chars
, opaque
);
66 /* Pointer to the current compression stream. */
68 static struct lto_compression_stream
*compression_stream
= NULL
;
70 /* Begin a new output section named NAME. If COMPRESS is true, zlib compress
74 lto_begin_section (const char *name
, bool compress
)
76 lang_hooks
.lto
.begin_section (name
);
78 /* FIXME lto: for now, suppress compression if the lang_hook that appends
79 data is anything other than assembler output. The effect here is that
80 we get compression of IL only in non-ltrans object files. */
81 gcc_assert (compression_stream
== NULL
);
83 compression_stream
= lto_start_compression (lto_append_data
, NULL
);
87 /* End the current output section. */
90 lto_end_section (void)
92 if (compression_stream
)
94 lto_end_compression (compression_stream
);
95 compression_stream
= NULL
;
97 lang_hooks
.lto
.end_section ();
101 /* Write all of the chars in OBS to the assembler. Recycle the blocks
102 in obs as this is being done. */
105 lto_write_stream (struct lto_output_stream
*obs
)
107 unsigned int block_size
= 1024;
108 struct lto_char_ptr_base
*block
;
109 struct lto_char_ptr_base
*next_block
;
110 if (!obs
->first_block
)
113 for (block
= obs
->first_block
; block
; block
= next_block
)
115 const char *base
= ((char *)block
) + sizeof (struct lto_char_ptr_base
);
116 unsigned int num_chars
= block_size
- sizeof (struct lto_char_ptr_base
);
118 /* If this is not the last block, it is full. If it is the last
119 block, left_in_block indicates how many chars are unoccupied in
120 this block; subtract from num_chars to obtain occupancy. */
121 next_block
= (struct lto_char_ptr_base
*) block
->ptr
;
123 num_chars
-= obs
->left_in_block
;
125 /* FIXME lto: WPA mode uses an ELF function as a lang_hook to append
126 output data. This hook is not happy with the way that compression
127 blocks up output differently to the way it's blocked here. So for
128 now, we don't compress WPA output. */
129 if (compression_stream
)
131 lto_compress_block (compression_stream
, base
, num_chars
);
132 lang_hooks
.lto
.append_data (NULL
, 0, block
);
135 lang_hooks
.lto
.append_data (base
, num_chars
, block
);
141 /* Adds a new block to output stream OBS. */
144 lto_append_block (struct lto_output_stream
*obs
)
146 struct lto_char_ptr_base
*new_block
;
148 gcc_assert (obs
->left_in_block
== 0);
150 if (obs
->first_block
== NULL
)
152 /* This is the first time the stream has been written
154 obs
->block_size
= 1024;
155 new_block
= (struct lto_char_ptr_base
*) xmalloc (obs
->block_size
);
156 obs
->first_block
= new_block
;
160 struct lto_char_ptr_base
*tptr
;
161 /* Get a new block that is twice as big as the last block
162 and link it into the list. */
163 obs
->block_size
*= 2;
164 new_block
= (struct lto_char_ptr_base
*) xmalloc (obs
->block_size
);
165 /* The first bytes of the block are reserved as a pointer to
166 the next block. Set the chain of the full block to the
167 pointer to the new block. */
168 tptr
= obs
->current_block
;
169 tptr
->ptr
= (char *) new_block
;
172 /* Set the place for the next char at the first position after the
173 chain to the next block. */
175 = ((char *) new_block
) + sizeof (struct lto_char_ptr_base
);
176 obs
->current_block
= new_block
;
177 /* Null out the newly allocated block's pointer to the next block. */
178 new_block
->ptr
= NULL
;
179 obs
->left_in_block
= obs
->block_size
- sizeof (struct lto_char_ptr_base
);
183 /* Write raw DATA of length LEN to the output block OB. */
186 lto_output_data_stream (struct lto_output_stream
*obs
, const void *data
,
194 if (obs
->left_in_block
== 0)
195 lto_append_block (obs
);
197 /* Determine how many bytes to copy in this loop. */
198 if (len
<= obs
->left_in_block
)
201 copy
= obs
->left_in_block
;
203 /* Copy the data and do bookkeeping. */
204 memcpy (obs
->current_pointer
, data
, copy
);
205 obs
->current_pointer
+= copy
;
206 obs
->total_size
+= copy
;
207 obs
->left_in_block
-= copy
;
208 data
= (const char *) data
+ copy
;
214 /* Lookup NAME in ENCODER. If NAME is not found, create a new entry in
215 ENCODER for NAME with the next available index of ENCODER, then
216 print the index to OBS. True is returned if NAME was added to
217 ENCODER. The resulting index is stored in THIS_INDEX.
219 If OBS is NULL, the only action is to add NAME to the encoder. */
222 lto_output_decl_index (struct lto_output_stream
*obs
,
223 struct lto_tree_ref_encoder
*encoder
,
224 tree name
, unsigned int *this_index
)
228 bool new_entry_p
= FALSE
;
231 slot
= encoder
->tree_hash_table
->insert (name
, &existed_p
);
234 index
= encoder
->trees
.length ();
236 encoder
->trees
.safe_push (name
);
243 streamer_write_uhwi_stream (obs
, index
);
248 /* Output a field DECL to OBS. */
251 lto_output_field_decl_index (struct lto_out_decl_state
*decl_state
,
252 struct lto_output_stream
* obs
, tree decl
)
255 lto_output_decl_index (obs
, &decl_state
->streams
[LTO_DECL_STREAM_FIELD_DECL
],
259 /* Output a function DECL to OBS. */
262 lto_output_fn_decl_index (struct lto_out_decl_state
*decl_state
,
263 struct lto_output_stream
* obs
, tree decl
)
266 lto_output_decl_index (obs
, &decl_state
->streams
[LTO_DECL_STREAM_FN_DECL
],
270 /* Output a namespace DECL to OBS. */
273 lto_output_namespace_decl_index (struct lto_out_decl_state
*decl_state
,
274 struct lto_output_stream
* obs
, tree decl
)
277 lto_output_decl_index (obs
,
278 &decl_state
->streams
[LTO_DECL_STREAM_NAMESPACE_DECL
],
282 /* Output a static or extern var DECL to OBS. */
285 lto_output_var_decl_index (struct lto_out_decl_state
*decl_state
,
286 struct lto_output_stream
* obs
, tree decl
)
289 lto_output_decl_index (obs
, &decl_state
->streams
[LTO_DECL_STREAM_VAR_DECL
],
293 /* Output a type DECL to OBS. */
296 lto_output_type_decl_index (struct lto_out_decl_state
*decl_state
,
297 struct lto_output_stream
* obs
, tree decl
)
300 lto_output_decl_index (obs
, &decl_state
->streams
[LTO_DECL_STREAM_TYPE_DECL
],
304 /* Output a type REF to OBS. */
307 lto_output_type_ref_index (struct lto_out_decl_state
*decl_state
,
308 struct lto_output_stream
*obs
, tree ref
)
311 lto_output_decl_index (obs
, &decl_state
->streams
[LTO_DECL_STREAM_TYPE
],
316 /* Create the output block and return it. */
318 struct lto_simple_output_block
*
319 lto_create_simple_output_block (enum lto_section_type section_type
)
321 struct lto_simple_output_block
*ob
322 = ((struct lto_simple_output_block
*)
323 xcalloc (1, sizeof (struct lto_simple_output_block
)));
325 ob
->section_type
= section_type
;
326 ob
->decl_state
= lto_get_out_decl_state ();
327 ob
->main_stream
= ((struct lto_output_stream
*)
328 xcalloc (1, sizeof (struct lto_output_stream
)));
334 /* Produce a simple section for one of the ipa passes. */
337 lto_destroy_simple_output_block (struct lto_simple_output_block
*ob
)
340 struct lto_simple_header header
;
341 struct lto_output_stream
*header_stream
;
343 section_name
= lto_get_section_name (ob
->section_type
, NULL
, NULL
);
344 lto_begin_section (section_name
, !flag_wpa
);
347 /* Write the header which says how to decode the pieces of the
349 memset (&header
, 0, sizeof (struct lto_simple_header
));
350 header
.lto_header
.major_version
= LTO_major_version
;
351 header
.lto_header
.minor_version
= LTO_minor_version
;
353 header
.compressed_size
= 0;
355 header
.main_size
= ob
->main_stream
->total_size
;
357 header_stream
= XCNEW (struct lto_output_stream
);
358 lto_output_data_stream (header_stream
, &header
, sizeof header
);
359 lto_write_stream (header_stream
);
360 free (header_stream
);
362 lto_write_stream (ob
->main_stream
);
364 /* Put back the assembly section that was there before we started
368 free (ob
->main_stream
);
373 /* Return a new lto_out_decl_state. */
375 struct lto_out_decl_state
*
376 lto_new_out_decl_state (void)
378 struct lto_out_decl_state
*state
= XCNEW (struct lto_out_decl_state
);
381 for (i
= 0; i
< LTO_N_DECL_STREAMS
; i
++)
382 lto_init_tree_ref_encoder (&state
->streams
[i
]);
388 /* Delete STATE and components. */
391 lto_delete_out_decl_state (struct lto_out_decl_state
*state
)
395 for (i
= 0; i
< LTO_N_DECL_STREAMS
; i
++)
396 lto_destroy_tree_ref_encoder (&state
->streams
[i
]);
402 /* Get the currently used lto_out_decl_state structure. */
404 struct lto_out_decl_state
*
405 lto_get_out_decl_state (void)
407 return decl_state_stack
.last ();
410 /* Push STATE to top of out decl stack. */
413 lto_push_out_decl_state (struct lto_out_decl_state
*state
)
415 decl_state_stack
.safe_push (state
);
418 /* Pop the currently used out-decl state from top of stack. */
420 struct lto_out_decl_state
*
421 lto_pop_out_decl_state (void)
423 return decl_state_stack
.pop ();
426 /* Record STATE after it has been used in serializing the body of
427 FN_DECL. STATE should no longer be used by the caller. The ownership
428 of it is taken over from this point. */
431 lto_record_function_out_decl_state (tree fn_decl
,
432 struct lto_out_decl_state
*state
)
436 /* Strip all hash tables to save some memory. */
437 for (i
= 0; i
< LTO_N_DECL_STREAMS
; i
++)
438 if (state
->streams
[i
].tree_hash_table
)
440 delete state
->streams
[i
].tree_hash_table
;
441 state
->streams
[i
].tree_hash_table
= NULL
;
443 state
->fn_decl
= fn_decl
;
444 lto_function_decl_states
.safe_push (state
);