2018-05-07 Edward Smith-Rowland <3dw4rd@verizon.net>
[official-gcc.git] / gcc / tree-streamer.c
blobe4689615310b2f76d5986514c0a1b9291711c0e9
1 /* Miscellaneous utilities for tree streaming. Things that are used
2 in both input and output are here.
4 Copyright (C) 2011-2018 Free Software Foundation, Inc.
5 Contributed by Diego Novillo <dnovillo@google.com>
7 This file is part of GCC.
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.
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.
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/>. */
23 #include "config.h"
24 #include "system.h"
25 #include "coretypes.h"
26 #include "backend.h"
27 #include "tree.h"
28 #include "gimple.h"
29 #include "tree-streamer.h"
30 #include "cgraph.h"
32 /* Table indexed by machine_mode, used for 2 different purposes.
33 During streaming out we record there non-zero value for all modes
34 that were streamed out.
35 During streaming in, we translate the on the disk mode using this
36 table. For normal LTO it is set to identity, for ACCEL_COMPILER
37 depending on the mode_table content. */
38 unsigned char streamer_mode_table[1 << 8];
40 /* Check that all the TS_* structures handled by the streamer_write_* and
41 streamer_read_* routines are exactly ALL the structures defined in
42 treestruct.def. */
44 void
45 streamer_check_handled_ts_structures (void)
47 bool handled_p[LAST_TS_ENUM];
48 unsigned i;
50 memset (&handled_p, 0, sizeof (handled_p));
52 /* These are the TS_* structures that are either handled or
53 explicitly ignored by the streamer routines. */
54 handled_p[TS_BASE] = true;
55 handled_p[TS_TYPED] = true;
56 handled_p[TS_COMMON] = true;
57 handled_p[TS_INT_CST] = true;
58 handled_p[TS_POLY_INT_CST] = true;
59 handled_p[TS_REAL_CST] = true;
60 handled_p[TS_FIXED_CST] = true;
61 handled_p[TS_VECTOR] = true;
62 handled_p[TS_STRING] = true;
63 handled_p[TS_COMPLEX] = true;
64 handled_p[TS_IDENTIFIER] = true;
65 handled_p[TS_DECL_MINIMAL] = true;
66 handled_p[TS_DECL_COMMON] = true;
67 handled_p[TS_DECL_WRTL] = true;
68 handled_p[TS_DECL_NON_COMMON] = true;
69 handled_p[TS_DECL_WITH_VIS] = true;
70 handled_p[TS_FIELD_DECL] = true;
71 handled_p[TS_VAR_DECL] = true;
72 handled_p[TS_PARM_DECL] = true;
73 handled_p[TS_LABEL_DECL] = true;
74 handled_p[TS_RESULT_DECL] = true;
75 handled_p[TS_CONST_DECL] = true;
76 handled_p[TS_TYPE_DECL] = true;
77 handled_p[TS_FUNCTION_DECL] = true;
78 handled_p[TS_TYPE_COMMON] = true;
79 handled_p[TS_TYPE_WITH_LANG_SPECIFIC] = true;
80 handled_p[TS_TYPE_NON_COMMON] = true;
81 handled_p[TS_LIST] = true;
82 handled_p[TS_VEC] = true;
83 handled_p[TS_EXP] = true;
84 handled_p[TS_SSA_NAME] = true;
85 handled_p[TS_BLOCK] = true;
86 handled_p[TS_BINFO] = true;
87 handled_p[TS_STATEMENT_LIST] = true;
88 handled_p[TS_CONSTRUCTOR] = true;
89 handled_p[TS_OMP_CLAUSE] = true;
90 handled_p[TS_OPTIMIZATION] = true;
91 handled_p[TS_TARGET_OPTION] = true;
92 handled_p[TS_TRANSLATION_UNIT_DECL] = true;
94 /* Anything not marked above will trigger the following assertion.
95 If this assertion triggers, it means that there is a new TS_*
96 structure that should be handled by the streamer. */
97 for (i = 0; i < LAST_TS_ENUM; i++)
98 gcc_assert (handled_p[i]);
102 /* Helper for streamer_tree_cache_insert_1. Add T to CACHE->NODES at
103 slot IX. */
105 static void
106 streamer_tree_cache_add_to_node_array (struct streamer_tree_cache_d *cache,
107 unsigned ix, tree t, hashval_t hash)
109 /* We're either replacing an old element or appending consecutively. */
110 if (cache->nodes.exists ())
112 if (cache->nodes.length () == ix)
113 cache->nodes.safe_push (t);
114 else
115 cache->nodes[ix] = t;
117 if (cache->hashes.exists ())
119 if (cache->hashes.length () == ix)
120 cache->hashes.safe_push (hash);
121 else
122 cache->hashes[ix] = hash;
127 /* Helper for streamer_tree_cache_insert and streamer_tree_cache_insert_at.
128 CACHE, T, and IX_P are as in streamer_tree_cache_insert.
130 If INSERT_AT_NEXT_SLOT_P is true, T is inserted at the next available
131 slot in the cache. Otherwise, T is inserted at the position indicated
132 in *IX_P.
134 If T already existed in CACHE, return true. Otherwise,
135 return false. */
137 static bool
138 streamer_tree_cache_insert_1 (struct streamer_tree_cache_d *cache,
139 tree t, hashval_t hash, unsigned *ix_p,
140 bool insert_at_next_slot_p)
142 bool existed_p;
144 gcc_assert (t);
146 unsigned int &ix = cache->node_map->get_or_insert (t, &existed_p);
147 if (!existed_p)
149 /* Determine the next slot to use in the cache. */
150 if (insert_at_next_slot_p)
151 ix = cache->next_idx++;
152 else
153 ix = *ix_p;
155 streamer_tree_cache_add_to_node_array (cache, ix, t, hash);
157 else
159 if (!insert_at_next_slot_p && ix != *ix_p)
161 /* If the caller wants to insert T at a specific slot
162 location, and ENTRY->TO does not match *IX_P, add T to
163 the requested location slot. */
164 ix = *ix_p;
165 streamer_tree_cache_add_to_node_array (cache, ix, t, hash);
169 if (ix_p)
170 *ix_p = ix;
172 return existed_p;
176 /* Insert tree node T in CACHE. If T already existed in the cache
177 return true. Otherwise, return false.
179 If IX_P is non-null, update it with the index into the cache where
180 T has been stored. */
182 bool
183 streamer_tree_cache_insert (struct streamer_tree_cache_d *cache, tree t,
184 hashval_t hash, unsigned *ix_p)
186 return streamer_tree_cache_insert_1 (cache, t, hash, ix_p, true);
190 /* Replace the tree node with T in CACHE at slot IX. */
192 void
193 streamer_tree_cache_replace_tree (struct streamer_tree_cache_d *cache,
194 tree t, unsigned ix)
196 hashval_t hash = 0;
197 if (cache->hashes.exists ())
198 hash = streamer_tree_cache_get_hash (cache, ix);
199 if (!cache->node_map)
200 streamer_tree_cache_add_to_node_array (cache, ix, t, hash);
201 else
202 streamer_tree_cache_insert_1 (cache, t, hash, &ix, false);
206 /* Appends tree node T to CACHE, even if T already existed in it. */
208 void
209 streamer_tree_cache_append (struct streamer_tree_cache_d *cache,
210 tree t, hashval_t hash)
212 unsigned ix = cache->next_idx++;
213 if (!cache->node_map)
214 streamer_tree_cache_add_to_node_array (cache, ix, t, hash);
215 else
216 streamer_tree_cache_insert_1 (cache, t, hash, &ix, false);
219 /* Return true if tree node T exists in CACHE, otherwise false. If IX_P is
220 not NULL, write to *IX_P the index into the cache where T is stored
221 ((unsigned)-1 if T is not found). */
223 bool
224 streamer_tree_cache_lookup (struct streamer_tree_cache_d *cache, tree t,
225 unsigned *ix_p)
227 unsigned *slot;
228 bool retval;
229 unsigned ix;
231 gcc_assert (t);
233 slot = cache->node_map->get (t);
234 if (slot == NULL)
236 retval = false;
237 ix = -1;
239 else
241 retval = true;
242 ix = *slot;
245 if (ix_p)
246 *ix_p = ix;
248 return retval;
252 /* Verify that NODE is in CACHE. */
254 static void
255 verify_common_node_recorded (struct streamer_tree_cache_d *cache, tree node)
257 /* Restrict this to flag_checking only because in general violating it is
258 harmless plus we never know what happens on all targets/frontend/flag(!)
259 combinations. */
260 if (!flag_checking)
261 return;
263 if (cache->node_map)
264 gcc_assert (streamer_tree_cache_lookup (cache, node, NULL));
265 else
267 bool found = false;
268 gcc_assert (cache->nodes.exists ());
269 /* Linear search... */
270 for (unsigned i = 0; !found && i < cache->nodes.length (); ++i)
271 if (cache->nodes[i] == node)
272 found = true;
273 gcc_assert (found);
278 /* Record NODE in CACHE. */
280 static void
281 record_common_node (struct streamer_tree_cache_d *cache, tree node)
283 /* If we recursively end up at nodes we do not want to preload simply don't.
284 ??? We'd want to verify that this doesn't happen, or alternatively
285 do not recurse at all. */
286 if (node == char_type_node)
287 return;
289 gcc_checking_assert (node != boolean_type_node
290 && node != boolean_true_node
291 && node != boolean_false_node);
293 /* We have to make sure to fill exactly the same number of
294 elements for all frontends. That can include NULL trees.
295 As our hash table can't deal with zero entries we'll simply stream
296 a random other tree. A NULL tree never will be looked up so it
297 doesn't matter which tree we replace it with, just to be sure
298 use error_mark_node. */
299 if (!node)
300 node = error_mark_node;
302 /* ??? FIXME, devise a better hash value. But the hash needs to be equal
303 for all frontend and lto1 invocations. So just use the position
304 in the cache as hash value. */
305 streamer_tree_cache_append (cache, node, cache->nodes.length ());
307 switch (TREE_CODE (node))
309 case ERROR_MARK:
310 case FIELD_DECL:
311 case FIXED_POINT_TYPE:
312 case IDENTIFIER_NODE:
313 case INTEGER_CST:
314 case INTEGER_TYPE:
315 case POINTER_BOUNDS_TYPE:
316 case REAL_TYPE:
317 case TREE_LIST:
318 case VOID_CST:
319 case VOID_TYPE:
320 /* No recursive trees. */
321 break;
322 case ARRAY_TYPE:
323 case POINTER_TYPE:
324 case REFERENCE_TYPE:
325 record_common_node (cache, TREE_TYPE (node));
326 break;
327 case COMPLEX_TYPE:
328 /* Verify that a complex type's component type (node_type) has been
329 handled already (and we thus don't need to recurse here). */
330 verify_common_node_recorded (cache, TREE_TYPE (node));
331 break;
332 case RECORD_TYPE:
333 /* The FIELD_DECLs of structures should be shared, so that every
334 COMPONENT_REF uses the same tree node when referencing a field.
335 Pointer equality between FIELD_DECLs is used by the alias
336 machinery to compute overlapping component references (see
337 nonoverlapping_component_refs_p and
338 nonoverlapping_component_refs_of_decl_p). */
339 for (tree f = TYPE_FIELDS (node); f; f = TREE_CHAIN (f))
340 record_common_node (cache, f);
341 break;
342 default:
343 /* Unexpected tree code. */
344 gcc_unreachable ();
349 /* Preload common nodes into CACHE and make sure they are merged
350 properly according to the gimple type table. */
352 static void
353 preload_common_nodes (struct streamer_tree_cache_d *cache)
355 unsigned i;
357 for (i = 0; i < itk_none; i++)
358 /* Skip itk_char. char_type_node is dependent on -f[un]signed-char. */
359 if (i != itk_char)
360 record_common_node (cache, integer_types[i]);
362 for (i = 0; i < stk_type_kind_last; i++)
363 record_common_node (cache, sizetype_tab[i]);
365 for (i = 0; i < TI_MAX; i++)
366 /* Skip boolean type and constants, they are frontend dependent. */
367 if (i != TI_BOOLEAN_TYPE
368 && i != TI_BOOLEAN_FALSE
369 && i != TI_BOOLEAN_TRUE
370 /* MAIN_IDENTIFIER is not always initialized by Fortran FE. */
371 && i != TI_MAIN_IDENTIFIER
372 /* PID_TYPE is initialized only by C family front-ends. */
373 && i != TI_PID_TYPE
374 /* Skip optimization and target option nodes; they depend on flags. */
375 && i != TI_OPTIMIZATION_DEFAULT
376 && i != TI_OPTIMIZATION_CURRENT
377 && i != TI_TARGET_OPTION_DEFAULT
378 && i != TI_TARGET_OPTION_CURRENT
379 && i != TI_CURRENT_TARGET_PRAGMA
380 && i != TI_CURRENT_OPTIMIZE_PRAGMA
381 /* Skip va_list* related nodes if offloading. For native LTO
382 we want them to be merged for the stdarg pass, for offloading
383 they might not be identical between host and offloading target. */
384 && (!lto_stream_offload_p
385 || (i != TI_VA_LIST_TYPE
386 && i != TI_VA_LIST_GPR_COUNTER_FIELD
387 && i != TI_VA_LIST_FPR_COUNTER_FIELD)))
388 record_common_node (cache, global_trees[i]);
392 /* Create a cache of pickled nodes. */
394 struct streamer_tree_cache_d *
395 streamer_tree_cache_create (bool with_hashes, bool with_map, bool with_vec)
397 struct streamer_tree_cache_d *cache;
399 cache = XCNEW (struct streamer_tree_cache_d);
401 if (with_map)
402 cache->node_map = new hash_map<tree, unsigned> (251);
403 cache->next_idx = 0;
404 if (with_vec)
405 cache->nodes.create (165);
406 if (with_hashes)
407 cache->hashes.create (165);
409 /* Load all the well-known tree nodes that are always created by
410 the compiler on startup. This prevents writing them out
411 unnecessarily. */
412 preload_common_nodes (cache);
414 return cache;
418 /* Delete the streamer cache C. */
420 void
421 streamer_tree_cache_delete (struct streamer_tree_cache_d *c)
423 if (c == NULL)
424 return;
426 delete c->node_map;
427 c->node_map = NULL;
428 c->nodes.release ();
429 c->hashes.release ();
430 free (c);