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b6f61163 | 1 | /* "Bag-of-pages" zone garbage collector for the GNU compiler. |
dae4174e | 2 | Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008 |
d9221e01 | 3 | Free Software Foundation, Inc. |
b6f61163 | 4 | |
08cee789 DJ |
5 | Contributed by Richard Henderson (rth@redhat.com) and Daniel Berlin |
6 | (dberlin@dberlin.org). Rewritten by Daniel Jacobowitz | |
7 | <dan@codesourcery.com>. | |
b6f61163 DB |
8 | |
9 | This file is part of GCC. | |
10 | ||
11 | GCC is free software; you can redistribute it and/or modify it under | |
12 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 13 | Software Foundation; either version 3, or (at your option) any later |
b6f61163 DB |
14 | version. |
15 | ||
16 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
17 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
18 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
19 | for more details. | |
20 | ||
21 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
22 | along with GCC; see the file COPYING3. If not see |
23 | <http://www.gnu.org/licenses/>. */ | |
b6f61163 DB |
24 | |
25 | #include "config.h" | |
26 | #include "system.h" | |
27 | #include "coretypes.h" | |
28 | #include "tm.h" | |
29 | #include "tree.h" | |
30 | #include "rtl.h" | |
31 | #include "tm_p.h" | |
32 | #include "toplev.h" | |
33 | #include "varray.h" | |
34 | #include "flags.h" | |
35 | #include "ggc.h" | |
36 | #include "timevar.h" | |
37 | #include "params.h" | |
38 | #include "bitmap.h" | |
ae2392a9 | 39 | #include "plugin.h" |
b6f61163 | 40 | |
b6f61163 DB |
41 | /* Prefer MAP_ANON(YMOUS) to /dev/zero, since we don't need to keep a |
42 | file open. Prefer either to valloc. */ | |
43 | #ifdef HAVE_MMAP_ANON | |
44 | # undef HAVE_MMAP_DEV_ZERO | |
45 | ||
46 | # include <sys/mman.h> | |
47 | # ifndef MAP_FAILED | |
48 | # define MAP_FAILED -1 | |
49 | # endif | |
50 | # if !defined (MAP_ANONYMOUS) && defined (MAP_ANON) | |
51 | # define MAP_ANONYMOUS MAP_ANON | |
52 | # endif | |
53 | # define USING_MMAP | |
b6f61163 DB |
54 | #endif |
55 | ||
56 | #ifdef HAVE_MMAP_DEV_ZERO | |
b6f61163 DB |
57 | # include <sys/mman.h> |
58 | # ifndef MAP_FAILED | |
59 | # define MAP_FAILED -1 | |
60 | # endif | |
61 | # define USING_MMAP | |
b6f61163 DB |
62 | #endif |
63 | ||
64 | #ifndef USING_MMAP | |
08cee789 | 65 | #error Zone collector requires mmap |
b6f61163 DB |
66 | #endif |
67 | ||
68 | #if (GCC_VERSION < 3001) | |
69 | #define prefetch(X) ((void) X) | |
08cee789 | 70 | #define prefetchw(X) ((void) X) |
b6f61163 DB |
71 | #else |
72 | #define prefetch(X) __builtin_prefetch (X) | |
08cee789 | 73 | #define prefetchw(X) __builtin_prefetch (X, 1, 3) |
b6f61163 DB |
74 | #endif |
75 | ||
08cee789 DJ |
76 | /* FUTURE NOTES: |
77 | ||
b6f61163 DB |
78 | If we track inter-zone pointers, we can mark single zones at a |
79 | time. | |
08cee789 | 80 | |
b6f61163 | 81 | If we have a zone where we guarantee no inter-zone pointers, we |
ba228239 | 82 | could mark that zone separately. |
08cee789 | 83 | |
b6f61163 DB |
84 | The garbage zone should not be marked, and we should return 1 in |
85 | ggc_set_mark for any object in the garbage zone, which cuts off | |
86 | marking quickly. */ | |
08cee789 | 87 | |
0fa2e4df | 88 | /* Strategy: |
b6f61163 DB |
89 | |
90 | This garbage-collecting allocator segregates objects into zones. | |
91 | It also segregates objects into "large" and "small" bins. Large | |
08cee789 | 92 | objects are greater than page size. |
b6f61163 | 93 | |
08cee789 DJ |
94 | Pages for small objects are broken up into chunks. The page has |
95 | a bitmap which marks the start position of each chunk (whether | |
96 | allocated or free). Free chunks are on one of the zone's free | |
97 | lists and contain a pointer to the next free chunk. Chunks in | |
98 | most of the free lists have a fixed size determined by the | |
99 | free list. Chunks in the "other" sized free list have their size | |
100 | stored right after their chain pointer. | |
b6f61163 DB |
101 | |
102 | Empty pages (of all sizes) are kept on a single page cache list, | |
103 | and are considered first when new pages are required; they are | |
104 | deallocated at the start of the next collection if they haven't | |
08cee789 | 105 | been recycled by then. The free page list is currently per-zone. */ |
b6f61163 DB |
106 | |
107 | /* Define GGC_DEBUG_LEVEL to print debugging information. | |
108 | 0: No debugging output. | |
109 | 1: GC statistics only. | |
110 | 2: Page-entry allocations/deallocations as well. | |
111 | 3: Object allocations as well. | |
112 | 4: Object marks as well. */ | |
113 | #define GGC_DEBUG_LEVEL (0) | |
114 | ||
115 | #ifndef HOST_BITS_PER_PTR | |
116 | #define HOST_BITS_PER_PTR HOST_BITS_PER_LONG | |
117 | #endif | |
9781b6da | 118 | |
08cee789 DJ |
119 | /* This structure manages small free chunks. The SIZE field is only |
120 | initialized if the chunk is in the "other" sized free list. Large | |
121 | chunks are allocated one at a time to their own page, and so don't | |
122 | come in here. */ | |
b6f61163 | 123 | |
08cee789 DJ |
124 | struct alloc_chunk { |
125 | struct alloc_chunk *next_free; | |
126 | unsigned int size; | |
127 | }; | |
b6f61163 | 128 | |
08cee789 DJ |
129 | /* The size of the fixed-size portion of a small page descriptor. */ |
130 | #define PAGE_OVERHEAD (offsetof (struct small_page_entry, alloc_bits)) | |
b6f61163 | 131 | |
08cee789 DJ |
132 | /* The collector's idea of the page size. This must be a power of two |
133 | no larger than the system page size, because pages must be aligned | |
134 | to this amount and are tracked at this granularity in the page | |
135 | table. We choose a size at compile time for efficiency. | |
b6f61163 | 136 | |
08cee789 DJ |
137 | We could make a better guess at compile time if PAGE_SIZE is a |
138 | constant in system headers, and PAGE_SHIFT is defined... */ | |
139 | #define GGC_PAGE_SIZE 4096 | |
140 | #define GGC_PAGE_MASK (GGC_PAGE_SIZE - 1) | |
141 | #define GGC_PAGE_SHIFT 12 | |
142 | ||
143 | #if 0 | |
144 | /* Alternative definitions which use the runtime page size. */ | |
145 | #define GGC_PAGE_SIZE G.pagesize | |
146 | #define GGC_PAGE_MASK G.page_mask | |
147 | #define GGC_PAGE_SHIFT G.lg_pagesize | |
b6f61163 | 148 | #endif |
b6f61163 | 149 | |
08cee789 DJ |
150 | /* The size of a small page managed by the garbage collector. This |
151 | must currently be GGC_PAGE_SIZE, but with a few changes could | |
152 | be any multiple of it to reduce certain kinds of overhead. */ | |
153 | #define SMALL_PAGE_SIZE GGC_PAGE_SIZE | |
b6f61163 | 154 | |
08cee789 DJ |
155 | /* Free bin information. These numbers may be in need of re-tuning. |
156 | In general, decreasing the number of free bins would seem to | |
157 | increase the time it takes to allocate... */ | |
b6f61163 | 158 | |
08cee789 DJ |
159 | /* FIXME: We can't use anything but MAX_ALIGNMENT for the bin size |
160 | today. */ | |
b6f61163 | 161 | |
b6f61163 | 162 | #define NUM_FREE_BINS 64 |
08cee789 | 163 | #define FREE_BIN_DELTA MAX_ALIGNMENT |
b6f61163 DB |
164 | #define SIZE_BIN_DOWN(SIZE) ((SIZE) / FREE_BIN_DELTA) |
165 | ||
08cee789 DJ |
166 | /* Allocation and marking parameters. */ |
167 | ||
168 | /* The smallest allocatable unit to keep track of. */ | |
169 | #define BYTES_PER_ALLOC_BIT MAX_ALIGNMENT | |
170 | ||
171 | /* The smallest markable unit. If we require each allocated object | |
172 | to contain at least two allocatable units, we can use half as many | |
173 | bits for the mark bitmap. But this adds considerable complexity | |
174 | to sweeping. */ | |
175 | #define BYTES_PER_MARK_BIT BYTES_PER_ALLOC_BIT | |
176 | ||
177 | #define BYTES_PER_MARK_WORD (8 * BYTES_PER_MARK_BIT * sizeof (mark_type)) | |
b6f61163 DB |
178 | |
179 | /* We use this structure to determine the alignment required for | |
08cee789 DJ |
180 | allocations. |
181 | ||
182 | There are several things wrong with this estimation of alignment. | |
183 | ||
184 | The maximum alignment for a structure is often less than the | |
185 | maximum alignment for a basic data type; for instance, on some | |
186 | targets long long must be aligned to sizeof (int) in a structure | |
187 | and sizeof (long long) in a variable. i386-linux is one example; | |
188 | Darwin is another (sometimes, depending on the compiler in use). | |
189 | ||
190 | Also, long double is not included. Nothing in GCC uses long | |
191 | double, so we assume that this is OK. On powerpc-darwin, adding | |
192 | long double would bring the maximum alignment up to 16 bytes, | |
193 | and until we need long double (or to vectorize compiler operations) | |
194 | that's painfully wasteful. This will need to change, some day. */ | |
b6f61163 DB |
195 | |
196 | struct max_alignment { | |
197 | char c; | |
198 | union { | |
199 | HOST_WIDEST_INT i; | |
b6f61163 | 200 | double d; |
b6f61163 DB |
201 | } u; |
202 | }; | |
203 | ||
204 | /* The biggest alignment required. */ | |
205 | ||
206 | #define MAX_ALIGNMENT (offsetof (struct max_alignment, u)) | |
207 | ||
b6f61163 DB |
208 | /* Compute the smallest multiple of F that is >= X. */ |
209 | ||
210 | #define ROUND_UP(x, f) (CEIL (x, f) * (f)) | |
211 | ||
08cee789 DJ |
212 | /* Types to use for the allocation and mark bitmaps. It might be |
213 | a good idea to add ffsl to libiberty and use unsigned long | |
214 | instead; that could speed us up where long is wider than int. */ | |
b6f61163 | 215 | |
08cee789 DJ |
216 | typedef unsigned int alloc_type; |
217 | typedef unsigned int mark_type; | |
218 | #define alloc_ffs(x) ffs(x) | |
219 | ||
220 | /* A page_entry records the status of an allocation page. This is the | |
221 | common data between all three kinds of pages - small, large, and | |
222 | PCH. */ | |
b6f61163 DB |
223 | typedef struct page_entry |
224 | { | |
08cee789 DJ |
225 | /* The address at which the memory is allocated. */ |
226 | char *page; | |
b6f61163 | 227 | |
08cee789 DJ |
228 | /* The zone that this page entry belongs to. */ |
229 | struct alloc_zone *zone; | |
b6f61163 | 230 | |
08cee789 | 231 | #ifdef GATHER_STATISTICS |
b6f61163 DB |
232 | /* How many collections we've survived. */ |
233 | size_t survived; | |
08cee789 | 234 | #endif |
b6f61163 DB |
235 | |
236 | /* Does this page contain small objects, or one large object? */ | |
237 | bool large_p; | |
238 | ||
08cee789 DJ |
239 | /* Is this page part of the loaded PCH? */ |
240 | bool pch_p; | |
b6f61163 DB |
241 | } page_entry; |
242 | ||
08cee789 DJ |
243 | /* Additional data needed for small pages. */ |
244 | struct small_page_entry | |
245 | { | |
246 | struct page_entry common; | |
247 | ||
248 | /* The next small page entry, or NULL if this is the last. */ | |
249 | struct small_page_entry *next; | |
250 | ||
251 | /* If currently marking this zone, a pointer to the mark bits | |
252 | for this page. If we aren't currently marking this zone, | |
253 | this pointer may be stale (pointing to freed memory). */ | |
254 | mark_type *mark_bits; | |
255 | ||
256 | /* The allocation bitmap. This array extends far enough to have | |
257 | one bit for every BYTES_PER_ALLOC_BIT bytes in the page. */ | |
258 | alloc_type alloc_bits[1]; | |
259 | }; | |
260 | ||
261 | /* Additional data needed for large pages. */ | |
262 | struct large_page_entry | |
263 | { | |
264 | struct page_entry common; | |
265 | ||
266 | /* The next large page entry, or NULL if this is the last. */ | |
267 | struct large_page_entry *next; | |
268 | ||
269 | /* The number of bytes allocated, not including the page entry. */ | |
270 | size_t bytes; | |
271 | ||
272 | /* The previous page in the list, so that we can unlink this one. */ | |
273 | struct large_page_entry *prev; | |
274 | ||
275 | /* During marking, is this object marked? */ | |
276 | bool mark_p; | |
277 | }; | |
278 | ||
279 | /* A two-level tree is used to look up the page-entry for a given | |
280 | pointer. Two chunks of the pointer's bits are extracted to index | |
281 | the first and second levels of the tree, as follows: | |
282 | ||
283 | HOST_PAGE_SIZE_BITS | |
284 | 32 | | | |
285 | msb +----------------+----+------+------+ lsb | |
286 | | | | | |
287 | PAGE_L1_BITS | | |
288 | | | | |
289 | PAGE_L2_BITS | |
290 | ||
291 | The bottommost HOST_PAGE_SIZE_BITS are ignored, since page-entry | |
292 | pages are aligned on system page boundaries. The next most | |
293 | significant PAGE_L2_BITS and PAGE_L1_BITS are the second and first | |
294 | index values in the lookup table, respectively. | |
295 | ||
296 | For 32-bit architectures and the settings below, there are no | |
297 | leftover bits. For architectures with wider pointers, the lookup | |
298 | tree points to a list of pages, which must be scanned to find the | |
299 | correct one. */ | |
300 | ||
301 | #define PAGE_L1_BITS (8) | |
302 | #define PAGE_L2_BITS (32 - PAGE_L1_BITS - GGC_PAGE_SHIFT) | |
303 | #define PAGE_L1_SIZE ((size_t) 1 << PAGE_L1_BITS) | |
304 | #define PAGE_L2_SIZE ((size_t) 1 << PAGE_L2_BITS) | |
305 | ||
306 | #define LOOKUP_L1(p) \ | |
307 | (((size_t) (p) >> (32 - PAGE_L1_BITS)) & ((1 << PAGE_L1_BITS) - 1)) | |
308 | ||
309 | #define LOOKUP_L2(p) \ | |
310 | (((size_t) (p) >> GGC_PAGE_SHIFT) & ((1 << PAGE_L2_BITS) - 1)) | |
311 | ||
312 | #if HOST_BITS_PER_PTR <= 32 | |
313 | ||
314 | /* On 32-bit hosts, we use a two level page table, as pictured above. */ | |
315 | typedef page_entry **page_table[PAGE_L1_SIZE]; | |
316 | ||
317 | #else | |
318 | ||
319 | /* On 64-bit hosts, we use the same two level page tables plus a linked | |
320 | list that disambiguates the top 32-bits. There will almost always be | |
321 | exactly one entry in the list. */ | |
322 | typedef struct page_table_chain | |
323 | { | |
324 | struct page_table_chain *next; | |
325 | size_t high_bits; | |
326 | page_entry **table[PAGE_L1_SIZE]; | |
327 | } *page_table; | |
328 | ||
329 | #endif | |
b6f61163 DB |
330 | |
331 | /* The global variables. */ | |
332 | static struct globals | |
333 | { | |
b6f61163 DB |
334 | /* The linked list of zones. */ |
335 | struct alloc_zone *zones; | |
336 | ||
08cee789 DJ |
337 | /* Lookup table for associating allocation pages with object addresses. */ |
338 | page_table lookup; | |
339 | ||
340 | /* The system's page size, and related constants. */ | |
b6f61163 DB |
341 | size_t pagesize; |
342 | size_t lg_pagesize; | |
08cee789 DJ |
343 | size_t page_mask; |
344 | ||
345 | /* The size to allocate for a small page entry. This includes | |
346 | the size of the structure and the size of the allocation | |
347 | bitmap. */ | |
348 | size_t small_page_overhead; | |
b6f61163 | 349 | |
b6f61163 | 350 | #if defined (HAVE_MMAP_DEV_ZERO) |
08cee789 | 351 | /* A file descriptor open to /dev/zero for reading. */ |
b6f61163 DB |
352 | int dev_zero_fd; |
353 | #endif | |
354 | ||
08cee789 DJ |
355 | /* Allocate pages in chunks of this size, to throttle calls to memory |
356 | allocation routines. The first page is used, the rest go onto the | |
357 | free list. */ | |
358 | size_t quire_size; | |
359 | ||
b6f61163 DB |
360 | /* The file descriptor for debugging output. */ |
361 | FILE *debug_file; | |
362 | } G; | |
363 | ||
08cee789 DJ |
364 | /* A zone allocation structure. There is one of these for every |
365 | distinct allocation zone. */ | |
b6f61163 DB |
366 | struct alloc_zone |
367 | { | |
08cee789 DJ |
368 | /* The most recent free chunk is saved here, instead of in the linked |
369 | free list, to decrease list manipulation. It is most likely that we | |
370 | will want this one. */ | |
371 | char *cached_free; | |
372 | size_t cached_free_size; | |
b6f61163 DB |
373 | |
374 | /* Linked lists of free storage. Slots 1 ... NUM_FREE_BINS have chunks of size | |
375 | FREE_BIN_DELTA. All other chunks are in slot 0. */ | |
376 | struct alloc_chunk *free_chunks[NUM_FREE_BINS + 1]; | |
377 | ||
08cee789 DJ |
378 | /* The highest bin index which might be non-empty. It may turn out |
379 | to be empty, in which case we have to search downwards. */ | |
380 | size_t high_free_bin; | |
381 | ||
382 | /* Bytes currently allocated in this zone. */ | |
b6f61163 DB |
383 | size_t allocated; |
384 | ||
08cee789 DJ |
385 | /* Linked list of the small pages in this zone. */ |
386 | struct small_page_entry *pages; | |
b6f61163 | 387 | |
08cee789 DJ |
388 | /* Doubly linked list of large pages in this zone. */ |
389 | struct large_page_entry *large_pages; | |
390 | ||
391 | /* If we are currently marking this zone, a pointer to the mark bits. */ | |
392 | mark_type *mark_bits; | |
393 | ||
394 | /* Name of the zone. */ | |
395 | const char *name; | |
b6f61163 | 396 | |
08cee789 DJ |
397 | /* The number of small pages currently allocated in this zone. */ |
398 | size_t n_small_pages; | |
b6f61163 | 399 | |
08cee789 DJ |
400 | /* Bytes allocated at the end of the last collection. */ |
401 | size_t allocated_last_gc; | |
b6f61163 | 402 | |
08cee789 DJ |
403 | /* Total amount of memory mapped. */ |
404 | size_t bytes_mapped; | |
b6f61163 DB |
405 | |
406 | /* A cache of free system pages. */ | |
08cee789 | 407 | struct small_page_entry *free_pages; |
b6f61163 | 408 | |
b6f61163 DB |
409 | /* Next zone in the linked list of zones. */ |
410 | struct alloc_zone *next_zone; | |
411 | ||
b944d187 | 412 | /* True if this zone was collected during this collection. */ |
b6f61163 | 413 | bool was_collected; |
b944d187 SB |
414 | |
415 | /* True if this zone should be destroyed after the next collection. */ | |
416 | bool dead; | |
b9bfca81 DJ |
417 | |
418 | #ifdef GATHER_STATISTICS | |
419 | struct | |
420 | { | |
421 | /* Total memory allocated with ggc_alloc. */ | |
422 | unsigned long long total_allocated; | |
423 | /* Total overhead for memory to be allocated with ggc_alloc. */ | |
424 | unsigned long long total_overhead; | |
425 | ||
426 | /* Total allocations and overhead for sizes less than 32, 64 and 128. | |
427 | These sizes are interesting because they are typical cache line | |
428 | sizes. */ | |
b8698a0f | 429 | |
b9bfca81 DJ |
430 | unsigned long long total_allocated_under32; |
431 | unsigned long long total_overhead_under32; | |
b8698a0f | 432 | |
b9bfca81 DJ |
433 | unsigned long long total_allocated_under64; |
434 | unsigned long long total_overhead_under64; | |
b8698a0f | 435 | |
b9bfca81 DJ |
436 | unsigned long long total_allocated_under128; |
437 | unsigned long long total_overhead_under128; | |
438 | } stats; | |
439 | #endif | |
b6f61163 DB |
440 | } main_zone; |
441 | ||
08cee789 DJ |
442 | /* Some default zones. */ |
443 | struct alloc_zone rtl_zone; | |
444 | struct alloc_zone tree_zone; | |
445 | struct alloc_zone tree_id_zone; | |
446 | ||
447 | /* The PCH zone does not need a normal zone structure, and it does | |
448 | not live on the linked list of zones. */ | |
449 | struct pch_zone | |
450 | { | |
451 | /* The start of the PCH zone. NULL if there is none. */ | |
452 | char *page; | |
453 | ||
454 | /* The end of the PCH zone. NULL if there is none. */ | |
455 | char *end; | |
456 | ||
457 | /* The size of the PCH zone. 0 if there is none. */ | |
458 | size_t bytes; | |
b6f61163 | 459 | |
08cee789 DJ |
460 | /* The allocation bitmap for the PCH zone. */ |
461 | alloc_type *alloc_bits; | |
b9bfca81 | 462 | |
08cee789 DJ |
463 | /* If we are currently marking, the mark bitmap for the PCH zone. |
464 | When it is first read in, we could avoid marking the PCH, | |
465 | because it will not contain any pointers to GC memory outside | |
466 | of the PCH; however, the PCH is currently mapped as writable, | |
467 | so we must mark it in case new pointers are added. */ | |
468 | mark_type *mark_bits; | |
469 | } pch_zone; | |
b6f61163 | 470 | |
b6f61163 DB |
471 | #ifdef USING_MMAP |
472 | static char *alloc_anon (char *, size_t, struct alloc_zone *); | |
473 | #endif | |
08cee789 DJ |
474 | static struct small_page_entry * alloc_small_page (struct alloc_zone *); |
475 | static struct large_page_entry * alloc_large_page (size_t, struct alloc_zone *); | |
476 | static void free_chunk (char *, size_t, struct alloc_zone *); | |
477 | static void free_small_page (struct small_page_entry *); | |
478 | static void free_large_page (struct large_page_entry *); | |
b6f61163 DB |
479 | static void release_pages (struct alloc_zone *); |
480 | static void sweep_pages (struct alloc_zone *); | |
b6f61163 | 481 | static bool ggc_collect_1 (struct alloc_zone *, bool); |
08cee789 DJ |
482 | static void new_ggc_zone_1 (struct alloc_zone *, const char *); |
483 | ||
484 | /* Traverse the page table and find the entry for a page. | |
485 | Die (probably) if the object wasn't allocated via GC. */ | |
486 | ||
487 | static inline page_entry * | |
488 | lookup_page_table_entry (const void *p) | |
489 | { | |
490 | page_entry ***base; | |
491 | size_t L1, L2; | |
492 | ||
493 | #if HOST_BITS_PER_PTR <= 32 | |
494 | base = &G.lookup[0]; | |
495 | #else | |
496 | page_table table = G.lookup; | |
497 | size_t high_bits = (size_t) p & ~ (size_t) 0xffffffff; | |
498 | while (table->high_bits != high_bits) | |
499 | table = table->next; | |
500 | base = &table->table[0]; | |
501 | #endif | |
502 | ||
503 | /* Extract the level 1 and 2 indices. */ | |
504 | L1 = LOOKUP_L1 (p); | |
505 | L2 = LOOKUP_L2 (p); | |
506 | ||
507 | return base[L1][L2]; | |
508 | } | |
509 | ||
dae4174e TT |
510 | /* Traverse the page table and find the entry for a page. |
511 | Return NULL if the object wasn't allocated via the GC. */ | |
512 | ||
513 | static inline page_entry * | |
514 | lookup_page_table_if_allocated (const void *p) | |
515 | { | |
516 | page_entry ***base; | |
517 | size_t L1, L2; | |
518 | ||
519 | #if HOST_BITS_PER_PTR <= 32 | |
520 | base = &G.lookup[0]; | |
521 | #else | |
522 | page_table table = G.lookup; | |
523 | size_t high_bits = (size_t) p & ~ (size_t) 0xffffffff; | |
524 | while (1) | |
525 | { | |
526 | if (table == NULL) | |
527 | return NULL; | |
528 | if (table->high_bits == high_bits) | |
529 | break; | |
530 | table = table->next; | |
531 | } | |
532 | base = &table->table[0]; | |
533 | #endif | |
534 | ||
535 | /* Extract the level 1 and 2 indices. */ | |
536 | L1 = LOOKUP_L1 (p); | |
537 | if (! base[L1]) | |
538 | return NULL; | |
539 | ||
540 | L2 = LOOKUP_L2 (p); | |
541 | if (L2 >= PAGE_L2_SIZE) | |
542 | return NULL; | |
543 | /* We might have a page entry which does not correspond exactly to a | |
544 | system page. */ | |
bf8e9c49 | 545 | if (base[L1][L2] && (const char *) p < base[L1][L2]->page) |
dae4174e TT |
546 | return NULL; |
547 | ||
548 | return base[L1][L2]; | |
549 | } | |
550 | ||
08cee789 DJ |
551 | /* Set the page table entry for the page that starts at P. If ENTRY |
552 | is NULL, clear the entry. */ | |
553 | ||
554 | static void | |
555 | set_page_table_entry (void *p, page_entry *entry) | |
556 | { | |
557 | page_entry ***base; | |
558 | size_t L1, L2; | |
559 | ||
560 | #if HOST_BITS_PER_PTR <= 32 | |
561 | base = &G.lookup[0]; | |
562 | #else | |
563 | page_table table; | |
564 | size_t high_bits = (size_t) p & ~ (size_t) 0xffffffff; | |
565 | for (table = G.lookup; table; table = table->next) | |
566 | if (table->high_bits == high_bits) | |
567 | goto found; | |
568 | ||
569 | /* Not found -- allocate a new table. */ | |
bf8e9c49 | 570 | table = XCNEW (struct page_table_chain); |
08cee789 DJ |
571 | table->next = G.lookup; |
572 | table->high_bits = high_bits; | |
573 | G.lookup = table; | |
574 | found: | |
575 | base = &table->table[0]; | |
576 | #endif | |
577 | ||
578 | /* Extract the level 1 and 2 indices. */ | |
579 | L1 = LOOKUP_L1 (p); | |
580 | L2 = LOOKUP_L2 (p); | |
581 | ||
582 | if (base[L1] == NULL) | |
bf8e9c49 | 583 | base[L1] = XCNEWVEC (page_entry *, PAGE_L2_SIZE); |
08cee789 DJ |
584 | |
585 | base[L1][L2] = entry; | |
586 | } | |
587 | ||
588 | /* Find the page table entry associated with OBJECT. */ | |
589 | ||
590 | static inline struct page_entry * | |
591 | zone_get_object_page (const void *object) | |
592 | { | |
593 | return lookup_page_table_entry (object); | |
594 | } | |
595 | ||
596 | /* Find which element of the alloc_bits array OBJECT should be | |
597 | recorded in. */ | |
598 | static inline unsigned int | |
599 | zone_get_object_alloc_word (const void *object) | |
600 | { | |
601 | return (((size_t) object & (GGC_PAGE_SIZE - 1)) | |
602 | / (8 * sizeof (alloc_type) * BYTES_PER_ALLOC_BIT)); | |
603 | } | |
604 | ||
605 | /* Find which bit of the appropriate word in the alloc_bits array | |
606 | OBJECT should be recorded in. */ | |
607 | static inline unsigned int | |
608 | zone_get_object_alloc_bit (const void *object) | |
609 | { | |
610 | return (((size_t) object / BYTES_PER_ALLOC_BIT) | |
611 | % (8 * sizeof (alloc_type))); | |
612 | } | |
613 | ||
614 | /* Find which element of the mark_bits array OBJECT should be recorded | |
615 | in. */ | |
616 | static inline unsigned int | |
617 | zone_get_object_mark_word (const void *object) | |
618 | { | |
619 | return (((size_t) object & (GGC_PAGE_SIZE - 1)) | |
620 | / (8 * sizeof (mark_type) * BYTES_PER_MARK_BIT)); | |
621 | } | |
622 | ||
623 | /* Find which bit of the appropriate word in the mark_bits array | |
624 | OBJECT should be recorded in. */ | |
625 | static inline unsigned int | |
626 | zone_get_object_mark_bit (const void *object) | |
627 | { | |
628 | return (((size_t) object / BYTES_PER_MARK_BIT) | |
629 | % (8 * sizeof (mark_type))); | |
630 | } | |
631 | ||
632 | /* Set the allocation bit corresponding to OBJECT in its page's | |
c1b97125 | 633 | bitmap. Used to split this object from the preceding one. */ |
08cee789 DJ |
634 | static inline void |
635 | zone_set_object_alloc_bit (const void *object) | |
636 | { | |
637 | struct small_page_entry *page | |
638 | = (struct small_page_entry *) zone_get_object_page (object); | |
639 | unsigned int start_word = zone_get_object_alloc_word (object); | |
640 | unsigned int start_bit = zone_get_object_alloc_bit (object); | |
641 | ||
642 | page->alloc_bits[start_word] |= 1L << start_bit; | |
643 | } | |
b6f61163 | 644 | |
08cee789 | 645 | /* Clear the allocation bit corresponding to OBJECT in PAGE's |
c1b97125 | 646 | bitmap. Used to coalesce this object with the preceding |
08cee789 DJ |
647 | one. */ |
648 | static inline void | |
649 | zone_clear_object_alloc_bit (struct small_page_entry *page, | |
650 | const void *object) | |
651 | { | |
652 | unsigned int start_word = zone_get_object_alloc_word (object); | |
653 | unsigned int start_bit = zone_get_object_alloc_bit (object); | |
654 | ||
655 | /* Would xor be quicker? */ | |
656 | page->alloc_bits[start_word] &= ~(1L << start_bit); | |
657 | } | |
658 | ||
659 | /* Find the size of the object which starts at START_WORD and | |
660 | START_BIT in ALLOC_BITS, which is at most MAX_SIZE bytes. | |
661 | Helper function for ggc_get_size and zone_find_object_size. */ | |
662 | ||
663 | static inline size_t | |
664 | zone_object_size_1 (alloc_type *alloc_bits, | |
665 | size_t start_word, size_t start_bit, | |
666 | size_t max_size) | |
667 | { | |
668 | size_t size; | |
669 | alloc_type alloc_word; | |
670 | int indx; | |
671 | ||
672 | /* Load the first word. */ | |
673 | alloc_word = alloc_bits[start_word++]; | |
674 | ||
675 | /* If that was the last bit in this word, we'll want to continue | |
676 | with the next word. Otherwise, handle the rest of this word. */ | |
677 | if (start_bit) | |
678 | { | |
679 | indx = alloc_ffs (alloc_word >> start_bit); | |
680 | if (indx) | |
681 | /* indx is 1-based. We started at the bit after the object's | |
682 | start, but we also ended at the bit after the object's end. | |
683 | It cancels out. */ | |
684 | return indx * BYTES_PER_ALLOC_BIT; | |
685 | ||
686 | /* The extra 1 accounts for the starting unit, before start_bit. */ | |
687 | size = (sizeof (alloc_type) * 8 - start_bit + 1) * BYTES_PER_ALLOC_BIT; | |
688 | ||
689 | if (size >= max_size) | |
690 | return max_size; | |
691 | ||
692 | alloc_word = alloc_bits[start_word++]; | |
693 | } | |
694 | else | |
695 | size = BYTES_PER_ALLOC_BIT; | |
696 | ||
697 | while (alloc_word == 0) | |
698 | { | |
699 | size += sizeof (alloc_type) * 8 * BYTES_PER_ALLOC_BIT; | |
700 | if (size >= max_size) | |
701 | return max_size; | |
702 | alloc_word = alloc_bits[start_word++]; | |
703 | } | |
b6f61163 | 704 | |
08cee789 DJ |
705 | indx = alloc_ffs (alloc_word); |
706 | return size + (indx - 1) * BYTES_PER_ALLOC_BIT; | |
707 | } | |
708 | ||
709 | /* Find the size of OBJECT on small page PAGE. */ | |
b6f61163 | 710 | |
08cee789 DJ |
711 | static inline size_t |
712 | zone_find_object_size (struct small_page_entry *page, | |
713 | const void *object) | |
b6f61163 | 714 | { |
08cee789 DJ |
715 | const char *object_midptr = (const char *) object + BYTES_PER_ALLOC_BIT; |
716 | unsigned int start_word = zone_get_object_alloc_word (object_midptr); | |
717 | unsigned int start_bit = zone_get_object_alloc_bit (object_midptr); | |
718 | size_t max_size = (page->common.page + SMALL_PAGE_SIZE | |
bf8e9c49 | 719 | - (const char *) object); |
08cee789 DJ |
720 | |
721 | return zone_object_size_1 (page->alloc_bits, start_word, start_bit, | |
722 | max_size); | |
723 | } | |
724 | ||
dae4174e TT |
725 | /* highest_bit assumes that alloc_type is 32 bits. */ |
726 | extern char check_alloc_type_size[(sizeof (alloc_type) == 4) ? 1 : -1]; | |
727 | ||
728 | /* Find the highest set bit in VALUE. Returns the bit number of that | |
729 | bit, using the same values as ffs. */ | |
730 | static inline alloc_type | |
731 | highest_bit (alloc_type value) | |
732 | { | |
733 | /* This also assumes that alloc_type is unsigned. */ | |
734 | value |= value >> 1; | |
735 | value |= value >> 2; | |
736 | value |= value >> 4; | |
737 | value |= value >> 8; | |
738 | value |= value >> 16; | |
739 | value = value ^ (value >> 1); | |
740 | return alloc_ffs (value); | |
741 | } | |
742 | ||
743 | /* Find the offset from the start of an object to P, which may point | |
744 | into the interior of the object. */ | |
745 | ||
746 | static unsigned long | |
747 | zone_find_object_offset (alloc_type *alloc_bits, size_t start_word, | |
748 | size_t start_bit) | |
749 | { | |
750 | unsigned int offset_in_bits; | |
751 | alloc_type alloc_word = alloc_bits[start_word]; | |
752 | ||
753 | /* Mask off any bits after the initial bit, but make sure to include | |
754 | the initial bit in the result. Note that START_BIT is | |
755 | 0-based. */ | |
756 | if (start_bit < 8 * sizeof (alloc_type) - 1) | |
757 | alloc_word &= (1 << (start_bit + 1)) - 1; | |
758 | offset_in_bits = start_bit; | |
759 | ||
760 | /* Search for the start of the object. */ | |
761 | while (alloc_word == 0 && start_word > 0) | |
762 | { | |
763 | alloc_word = alloc_bits[--start_word]; | |
764 | offset_in_bits += 8 * sizeof (alloc_type); | |
765 | } | |
766 | /* We must always find a set bit. */ | |
767 | gcc_assert (alloc_word != 0); | |
768 | /* Note that the result of highest_bit is 1-based. */ | |
769 | offset_in_bits -= highest_bit (alloc_word) - 1; | |
770 | ||
771 | return BYTES_PER_ALLOC_BIT * offset_in_bits; | |
772 | } | |
773 | ||
08cee789 DJ |
774 | /* Allocate the mark bits for every zone, and set the pointers on each |
775 | page. */ | |
776 | static void | |
777 | zone_allocate_marks (void) | |
778 | { | |
779 | struct alloc_zone *zone; | |
780 | ||
781 | for (zone = G.zones; zone; zone = zone->next_zone) | |
782 | { | |
783 | struct small_page_entry *page; | |
784 | mark_type *cur_marks; | |
785 | size_t mark_words, mark_words_per_page; | |
786 | #ifdef ENABLE_CHECKING | |
787 | size_t n = 0; | |
b6f61163 | 788 | #endif |
08cee789 DJ |
789 | |
790 | mark_words_per_page | |
791 | = (GGC_PAGE_SIZE + BYTES_PER_MARK_WORD - 1) / BYTES_PER_MARK_WORD; | |
792 | mark_words = zone->n_small_pages * mark_words_per_page; | |
793 | zone->mark_bits = (mark_type *) xcalloc (sizeof (mark_type), | |
794 | mark_words); | |
795 | cur_marks = zone->mark_bits; | |
796 | for (page = zone->pages; page; page = page->next) | |
797 | { | |
798 | page->mark_bits = cur_marks; | |
799 | cur_marks += mark_words_per_page; | |
800 | #ifdef ENABLE_CHECKING | |
801 | n++; | |
802 | #endif | |
803 | } | |
804 | #ifdef ENABLE_CHECKING | |
805 | gcc_assert (n == zone->n_small_pages); | |
806 | #endif | |
807 | } | |
808 | ||
809 | /* We don't collect the PCH zone, but we do have to mark it | |
810 | (for now). */ | |
811 | if (pch_zone.bytes) | |
812 | pch_zone.mark_bits | |
813 | = (mark_type *) xcalloc (sizeof (mark_type), | |
814 | CEIL (pch_zone.bytes, BYTES_PER_MARK_WORD)); | |
b6f61163 DB |
815 | } |
816 | ||
08cee789 DJ |
817 | /* After marking and sweeping, release the memory used for mark bits. */ |
818 | static void | |
819 | zone_free_marks (void) | |
820 | { | |
821 | struct alloc_zone *zone; | |
822 | ||
823 | for (zone = G.zones; zone; zone = zone->next_zone) | |
824 | if (zone->mark_bits) | |
825 | { | |
826 | free (zone->mark_bits); | |
827 | zone->mark_bits = NULL; | |
828 | } | |
829 | ||
830 | if (pch_zone.bytes) | |
831 | { | |
832 | free (pch_zone.mark_bits); | |
833 | pch_zone.mark_bits = NULL; | |
834 | } | |
835 | } | |
b6f61163 DB |
836 | |
837 | #ifdef USING_MMAP | |
838 | /* Allocate SIZE bytes of anonymous memory, preferably near PREF, | |
839 | (if non-null). The ifdef structure here is intended to cause a | |
840 | compile error unless exactly one of the HAVE_* is defined. */ | |
841 | ||
842 | static inline char * | |
843 | alloc_anon (char *pref ATTRIBUTE_UNUSED, size_t size, struct alloc_zone *zone) | |
844 | { | |
845 | #ifdef HAVE_MMAP_ANON | |
846 | char *page = (char *) mmap (pref, size, PROT_READ | PROT_WRITE, | |
847 | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); | |
848 | #endif | |
849 | #ifdef HAVE_MMAP_DEV_ZERO | |
850 | char *page = (char *) mmap (pref, size, PROT_READ | PROT_WRITE, | |
851 | MAP_PRIVATE, G.dev_zero_fd, 0); | |
852 | #endif | |
b6f61163 DB |
853 | |
854 | if (page == (char *) MAP_FAILED) | |
855 | { | |
856 | perror ("virtual memory exhausted"); | |
857 | exit (FATAL_EXIT_CODE); | |
858 | } | |
859 | ||
860 | /* Remember that we allocated this memory. */ | |
861 | zone->bytes_mapped += size; | |
08cee789 | 862 | |
b6f61163 DB |
863 | /* Pretend we don't have access to the allocated pages. We'll enable |
864 | access to smaller pieces of the area in ggc_alloc. Discard the | |
865 | handle to avoid handle leak. */ | |
35dee980 | 866 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (page, size)); |
08cee789 | 867 | |
b6f61163 DB |
868 | return page; |
869 | } | |
870 | #endif | |
b6f61163 | 871 | |
08cee789 DJ |
872 | /* Allocate a new page for allocating small objects in ZONE, and |
873 | return an entry for it. */ | |
b6f61163 | 874 | |
08cee789 | 875 | static struct small_page_entry * |
b6f61163 DB |
876 | alloc_small_page (struct alloc_zone *zone) |
877 | { | |
08cee789 | 878 | struct small_page_entry *entry; |
b6f61163 DB |
879 | |
880 | /* Check the list of free pages for one we can use. */ | |
881 | entry = zone->free_pages; | |
882 | if (entry != NULL) | |
883 | { | |
884 | /* Recycle the allocated memory from this page ... */ | |
885 | zone->free_pages = entry->next; | |
b6f61163 | 886 | } |
b6f61163 DB |
887 | else |
888 | { | |
889 | /* We want just one page. Allocate a bunch of them and put the | |
890 | extras on the freelist. (Can only do this optimization with | |
891 | mmap for backing store.) */ | |
08cee789 | 892 | struct small_page_entry *e, *f = zone->free_pages; |
b6f61163 | 893 | int i; |
08cee789 | 894 | char *page; |
b6f61163 | 895 | |
08cee789 | 896 | page = alloc_anon (NULL, GGC_PAGE_SIZE * G.quire_size, zone); |
b6f61163 DB |
897 | |
898 | /* This loop counts down so that the chain will be in ascending | |
899 | memory order. */ | |
08cee789 | 900 | for (i = G.quire_size - 1; i >= 1; i--) |
b6f61163 | 901 | { |
bf8e9c49 | 902 | e = XCNEWVAR (struct small_page_entry, G.small_page_overhead); |
08cee789 DJ |
903 | e->common.page = page + (i << GGC_PAGE_SHIFT); |
904 | e->common.zone = zone; | |
b6f61163 DB |
905 | e->next = f; |
906 | f = e; | |
08cee789 | 907 | set_page_table_entry (e->common.page, &e->common); |
b6f61163 DB |
908 | } |
909 | ||
910 | zone->free_pages = f; | |
08cee789 | 911 | |
bf8e9c49 | 912 | entry = XCNEWVAR (struct small_page_entry, G.small_page_overhead); |
08cee789 DJ |
913 | entry->common.page = page; |
914 | entry->common.zone = zone; | |
915 | set_page_table_entry (page, &entry->common); | |
b6f61163 | 916 | } |
b6f61163 | 917 | |
08cee789 | 918 | zone->n_small_pages++; |
b6f61163 | 919 | |
b6f61163 DB |
920 | if (GGC_DEBUG_LEVEL >= 2) |
921 | fprintf (G.debug_file, | |
08cee789 DJ |
922 | "Allocating %s page at %p, data %p-%p\n", |
923 | entry->common.zone->name, (PTR) entry, entry->common.page, | |
924 | entry->common.page + SMALL_PAGE_SIZE - 1); | |
b6f61163 DB |
925 | |
926 | return entry; | |
927 | } | |
928 | ||
929 | /* Allocate a large page of size SIZE in ZONE. */ | |
930 | ||
08cee789 | 931 | static struct large_page_entry * |
b6f61163 DB |
932 | alloc_large_page (size_t size, struct alloc_zone *zone) |
933 | { | |
08cee789 | 934 | struct large_page_entry *entry; |
b6f61163 | 935 | char *page; |
08cee789 DJ |
936 | size_t needed_size; |
937 | ||
938 | needed_size = size + sizeof (struct large_page_entry); | |
bf8e9c49 | 939 | page = XNEWVAR (char, needed_size); |
b6f61163 | 940 | |
08cee789 DJ |
941 | entry = (struct large_page_entry *) page; |
942 | ||
943 | entry->next = NULL; | |
944 | entry->common.page = page + sizeof (struct large_page_entry); | |
945 | entry->common.large_p = true; | |
946 | entry->common.pch_p = false; | |
947 | entry->common.zone = zone; | |
948 | #ifdef GATHER_STATISTICS | |
949 | entry->common.survived = 0; | |
950 | #endif | |
951 | entry->mark_p = false; | |
b6f61163 | 952 | entry->bytes = size; |
08cee789 DJ |
953 | entry->prev = NULL; |
954 | ||
955 | set_page_table_entry (entry->common.page, &entry->common); | |
b6f61163 | 956 | |
b6f61163 DB |
957 | if (GGC_DEBUG_LEVEL >= 2) |
958 | fprintf (G.debug_file, | |
08cee789 DJ |
959 | "Allocating %s large page at %p, data %p-%p\n", |
960 | entry->common.zone->name, (PTR) entry, entry->common.page, | |
961 | entry->common.page + SMALL_PAGE_SIZE - 1); | |
b6f61163 DB |
962 | |
963 | return entry; | |
964 | } | |
965 | ||
966 | ||
967 | /* For a page that is no longer needed, put it on the free page list. */ | |
968 | ||
969 | static inline void | |
08cee789 | 970 | free_small_page (struct small_page_entry *entry) |
b6f61163 DB |
971 | { |
972 | if (GGC_DEBUG_LEVEL >= 2) | |
973 | fprintf (G.debug_file, | |
08cee789 DJ |
974 | "Deallocating %s page at %p, data %p-%p\n", |
975 | entry->common.zone->name, (PTR) entry, | |
976 | entry->common.page, entry->common.page + SMALL_PAGE_SIZE - 1); | |
b6f61163 | 977 | |
08cee789 | 978 | gcc_assert (!entry->common.large_p); |
b6f61163 | 979 | |
08cee789 DJ |
980 | /* Mark the page as inaccessible. Discard the handle to |
981 | avoid handle leak. */ | |
35dee980 HPN |
982 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (entry->common.page, |
983 | SMALL_PAGE_SIZE)); | |
08cee789 DJ |
984 | |
985 | entry->next = entry->common.zone->free_pages; | |
986 | entry->common.zone->free_pages = entry; | |
987 | entry->common.zone->n_small_pages--; | |
988 | } | |
989 | ||
990 | /* Release a large page that is no longer needed. */ | |
991 | ||
992 | static inline void | |
993 | free_large_page (struct large_page_entry *entry) | |
994 | { | |
995 | if (GGC_DEBUG_LEVEL >= 2) | |
996 | fprintf (G.debug_file, | |
997 | "Deallocating %s page at %p, data %p-%p\n", | |
998 | entry->common.zone->name, (PTR) entry, | |
999 | entry->common.page, entry->common.page + SMALL_PAGE_SIZE - 1); | |
1000 | ||
1001 | gcc_assert (entry->common.large_p); | |
1002 | ||
1003 | set_page_table_entry (entry->common.page, NULL); | |
1004 | free (entry); | |
b6f61163 DB |
1005 | } |
1006 | ||
1007 | /* Release the free page cache to the system. */ | |
1008 | ||
1009 | static void | |
1010 | release_pages (struct alloc_zone *zone) | |
1011 | { | |
1012 | #ifdef USING_MMAP | |
08cee789 | 1013 | struct small_page_entry *p, *next; |
b6f61163 DB |
1014 | char *start; |
1015 | size_t len; | |
1016 | ||
1017 | /* Gather up adjacent pages so they are unmapped together. */ | |
1018 | p = zone->free_pages; | |
1019 | ||
1020 | while (p) | |
1021 | { | |
08cee789 | 1022 | start = p->common.page; |
b6f61163 | 1023 | next = p->next; |
08cee789 DJ |
1024 | len = SMALL_PAGE_SIZE; |
1025 | set_page_table_entry (p->common.page, NULL); | |
b6f61163 DB |
1026 | p = next; |
1027 | ||
08cee789 | 1028 | while (p && p->common.page == start + len) |
b6f61163 DB |
1029 | { |
1030 | next = p->next; | |
08cee789 DJ |
1031 | len += SMALL_PAGE_SIZE; |
1032 | set_page_table_entry (p->common.page, NULL); | |
b6f61163 DB |
1033 | p = next; |
1034 | } | |
1035 | ||
1036 | munmap (start, len); | |
1037 | zone->bytes_mapped -= len; | |
1038 | } | |
1039 | ||
1040 | zone->free_pages = NULL; | |
1041 | #endif | |
b6f61163 DB |
1042 | } |
1043 | ||
08cee789 | 1044 | /* Place the block at PTR of size SIZE on the free list for ZONE. */ |
b6f61163 DB |
1045 | |
1046 | static inline void | |
08cee789 | 1047 | free_chunk (char *ptr, size_t size, struct alloc_zone *zone) |
b6f61163 | 1048 | { |
08cee789 | 1049 | struct alloc_chunk *chunk = (struct alloc_chunk *) ptr; |
b6f61163 DB |
1050 | size_t bin = 0; |
1051 | ||
1052 | bin = SIZE_BIN_DOWN (size); | |
08cee789 | 1053 | gcc_assert (bin != 0); |
b6f61163 | 1054 | if (bin > NUM_FREE_BINS) |
08cee789 DJ |
1055 | { |
1056 | bin = 0; | |
35dee980 HPN |
1057 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (chunk, |
1058 | sizeof (struct | |
1059 | alloc_chunk))); | |
08cee789 DJ |
1060 | chunk->size = size; |
1061 | chunk->next_free = zone->free_chunks[bin]; | |
35dee980 HPN |
1062 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (ptr |
1063 | + sizeof (struct | |
1064 | alloc_chunk), | |
1065 | size | |
1066 | - sizeof (struct | |
1067 | alloc_chunk))); | |
08cee789 DJ |
1068 | } |
1069 | else | |
1070 | { | |
35dee980 HPN |
1071 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (chunk, |
1072 | sizeof (struct | |
1073 | alloc_chunk *))); | |
08cee789 | 1074 | chunk->next_free = zone->free_chunks[bin]; |
35dee980 HPN |
1075 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (ptr |
1076 | + sizeof (struct | |
1077 | alloc_chunk *), | |
1078 | size | |
1079 | - sizeof (struct | |
1080 | alloc_chunk *))); | |
08cee789 DJ |
1081 | } |
1082 | ||
b6f61163 | 1083 | zone->free_chunks[bin] = chunk; |
08cee789 DJ |
1084 | if (bin > zone->high_free_bin) |
1085 | zone->high_free_bin = bin; | |
b6f61163 DB |
1086 | if (GGC_DEBUG_LEVEL >= 3) |
1087 | fprintf (G.debug_file, "Deallocating object, chunk=%p\n", (void *)chunk); | |
b6f61163 DB |
1088 | } |
1089 | ||
08cee789 | 1090 | /* Allocate a chunk of memory of at least ORIG_SIZE bytes, in ZONE. */ |
b6f61163 | 1091 | |
08cee789 DJ |
1092 | void * |
1093 | ggc_alloc_zone_stat (size_t orig_size, struct alloc_zone *zone | |
1094 | MEM_STAT_DECL) | |
b6f61163 | 1095 | { |
08cee789 DJ |
1096 | size_t bin; |
1097 | size_t csize; | |
1098 | struct small_page_entry *entry; | |
1099 | struct alloc_chunk *chunk, **pp; | |
b6f61163 | 1100 | void *result; |
b9bfca81 | 1101 | size_t size = orig_size; |
b6f61163 | 1102 | |
08cee789 DJ |
1103 | /* Make sure that zero-sized allocations get a unique and freeable |
1104 | pointer. */ | |
1105 | if (size == 0) | |
1106 | size = MAX_ALIGNMENT; | |
1107 | else | |
1108 | size = (size + MAX_ALIGNMENT - 1) & -MAX_ALIGNMENT; | |
1109 | ||
1110 | /* Try to allocate the object from several different sources. Each | |
1111 | of these cases is responsible for setting RESULT and SIZE to | |
1112 | describe the allocated block, before jumping to FOUND. If a | |
1113 | chunk is split, the allocate bit for the new chunk should also be | |
1114 | set. | |
1115 | ||
1116 | Large objects are handled specially. However, they'll just fail | |
1117 | the next couple of conditions, so we can wait to check for them | |
1118 | below. The large object case is relatively rare (< 1%), so this | |
1119 | is a win. */ | |
1120 | ||
1121 | /* First try to split the last chunk we allocated. For best | |
1122 | fragmentation behavior it would be better to look for a | |
1123 | free bin of the appropriate size for a small object. However, | |
1124 | we're unlikely (1% - 7%) to find one, and this gives better | |
1125 | locality behavior anyway. This case handles the lion's share | |
1126 | of all calls to this function. */ | |
1127 | if (size <= zone->cached_free_size) | |
1128 | { | |
1129 | result = zone->cached_free; | |
1130 | ||
1131 | zone->cached_free_size -= size; | |
1132 | if (zone->cached_free_size) | |
1133 | { | |
1134 | zone->cached_free += size; | |
1135 | zone_set_object_alloc_bit (zone->cached_free); | |
1136 | } | |
1137 | ||
1138 | goto found; | |
1139 | } | |
1140 | ||
1141 | /* Next, try to find a free bin of the exactly correct size. */ | |
1142 | ||
1143 | /* We want to round SIZE up, rather than down, but we know it's | |
1144 | already aligned to at least FREE_BIN_DELTA, so we can just | |
1145 | shift. */ | |
1146 | bin = SIZE_BIN_DOWN (size); | |
b6f61163 | 1147 | |
08cee789 DJ |
1148 | if (bin <= NUM_FREE_BINS |
1149 | && (chunk = zone->free_chunks[bin]) != NULL) | |
b6f61163 | 1150 | { |
08cee789 DJ |
1151 | /* We have a chunk of the right size. Pull it off the free list |
1152 | and use it. */ | |
b6f61163 | 1153 | |
08cee789 DJ |
1154 | zone->free_chunks[bin] = chunk->next_free; |
1155 | ||
1156 | /* NOTE: SIZE is only guaranteed to be right if MAX_ALIGNMENT | |
1157 | == FREE_BIN_DELTA. */ | |
1158 | result = chunk; | |
1159 | ||
1160 | /* The allocation bits are already set correctly. HIGH_FREE_BIN | |
1161 | may now be wrong, if this was the last chunk in the high bin. | |
1162 | Rather than fixing it up now, wait until we need to search | |
1163 | the free bins. */ | |
b6f61163 DB |
1164 | |
1165 | goto found; | |
1166 | } | |
1167 | ||
08cee789 DJ |
1168 | /* Next, if there wasn't a chunk of the ideal size, look for a chunk |
1169 | to split. We can find one in the too-big bin, or in the largest | |
1170 | sized bin with a chunk in it. Try the largest normal-sized bin | |
1171 | first. */ | |
1172 | ||
1173 | if (zone->high_free_bin > bin) | |
b6f61163 | 1174 | { |
08cee789 DJ |
1175 | /* Find the highest numbered free bin. It will be at or below |
1176 | the watermark. */ | |
1177 | while (zone->high_free_bin > bin | |
1178 | && zone->free_chunks[zone->high_free_bin] == NULL) | |
1179 | zone->high_free_bin--; | |
1180 | ||
1181 | if (zone->high_free_bin > bin) | |
b6f61163 | 1182 | { |
08cee789 DJ |
1183 | size_t tbin = zone->high_free_bin; |
1184 | chunk = zone->free_chunks[tbin]; | |
1185 | ||
1186 | /* Remove the chunk from its previous bin. */ | |
1187 | zone->free_chunks[tbin] = chunk->next_free; | |
1188 | ||
1189 | result = (char *) chunk; | |
1190 | ||
1191 | /* Save the rest of the chunk for future allocation. */ | |
1192 | if (zone->cached_free_size) | |
1193 | free_chunk (zone->cached_free, zone->cached_free_size, zone); | |
1194 | ||
1195 | chunk = (struct alloc_chunk *) ((char *) result + size); | |
1196 | zone->cached_free = (char *) chunk; | |
1197 | zone->cached_free_size = (tbin - bin) * FREE_BIN_DELTA; | |
1198 | ||
1199 | /* Mark the new free chunk as an object, so that we can | |
1200 | find the size of the newly allocated object. */ | |
1201 | zone_set_object_alloc_bit (chunk); | |
1202 | ||
1203 | /* HIGH_FREE_BIN may now be wrong, if this was the last | |
1204 | chunk in the high bin. Rather than fixing it up now, | |
1205 | wait until we need to search the free bins. */ | |
1206 | ||
b6f61163 DB |
1207 | goto found; |
1208 | } | |
1209 | } | |
1210 | ||
1211 | /* Failing that, look through the "other" bucket for a chunk | |
1212 | that is large enough. */ | |
1213 | pp = &(zone->free_chunks[0]); | |
1214 | chunk = *pp; | |
1215 | while (chunk && chunk->size < size) | |
1216 | { | |
08cee789 | 1217 | pp = &chunk->next_free; |
b6f61163 DB |
1218 | chunk = *pp; |
1219 | } | |
1220 | ||
08cee789 | 1221 | if (chunk) |
b6f61163 | 1222 | { |
08cee789 DJ |
1223 | /* Remove the chunk from its previous bin. */ |
1224 | *pp = chunk->next_free; | |
b6f61163 | 1225 | |
08cee789 DJ |
1226 | result = (char *) chunk; |
1227 | ||
1228 | /* Save the rest of the chunk for future allocation, if there's any | |
1229 | left over. */ | |
1230 | csize = chunk->size; | |
1231 | if (csize > size) | |
1232 | { | |
1233 | if (zone->cached_free_size) | |
1234 | free_chunk (zone->cached_free, zone->cached_free_size, zone); | |
1235 | ||
1236 | chunk = (struct alloc_chunk *) ((char *) result + size); | |
1237 | zone->cached_free = (char *) chunk; | |
1238 | zone->cached_free_size = csize - size; | |
1239 | ||
1240 | /* Mark the new free chunk as an object. */ | |
1241 | zone_set_object_alloc_bit (chunk); | |
1242 | } | |
1243 | ||
1244 | goto found; | |
b6f61163 | 1245 | } |
08cee789 DJ |
1246 | |
1247 | /* Handle large allocations. We could choose any threshold between | |
1248 | GGC_PAGE_SIZE - sizeof (struct large_page_entry) and | |
1249 | GGC_PAGE_SIZE. It can't be smaller, because then it wouldn't | |
1250 | be guaranteed to have a unique entry in the lookup table. Large | |
1251 | allocations will always fall through to here. */ | |
1252 | if (size > GGC_PAGE_SIZE) | |
b6f61163 | 1253 | { |
08cee789 DJ |
1254 | struct large_page_entry *entry = alloc_large_page (size, zone); |
1255 | ||
1256 | #ifdef GATHER_STATISTICS | |
1257 | entry->common.survived = 0; | |
1258 | #endif | |
1259 | ||
1260 | entry->next = zone->large_pages; | |
1261 | if (zone->large_pages) | |
1262 | zone->large_pages->prev = entry; | |
1263 | zone->large_pages = entry; | |
1264 | ||
1265 | result = entry->common.page; | |
1266 | ||
1267 | goto found; | |
b6f61163 | 1268 | } |
08cee789 DJ |
1269 | |
1270 | /* Failing everything above, allocate a new small page. */ | |
1271 | ||
1272 | entry = alloc_small_page (zone); | |
1273 | entry->next = zone->pages; | |
1274 | zone->pages = entry; | |
1275 | ||
1276 | /* Mark the first chunk in the new page. */ | |
1277 | entry->alloc_bits[0] = 1; | |
1278 | ||
1279 | result = entry->common.page; | |
1280 | if (size < SMALL_PAGE_SIZE) | |
b6f61163 | 1281 | { |
08cee789 DJ |
1282 | if (zone->cached_free_size) |
1283 | free_chunk (zone->cached_free, zone->cached_free_size, zone); | |
b6f61163 | 1284 | |
08cee789 DJ |
1285 | zone->cached_free = (char *) result + size; |
1286 | zone->cached_free_size = SMALL_PAGE_SIZE - size; | |
1287 | ||
1288 | /* Mark the new free chunk as an object. */ | |
1289 | zone_set_object_alloc_bit (zone->cached_free); | |
b6f61163 | 1290 | } |
92e838e2 | 1291 | |
b6f61163 | 1292 | found: |
08cee789 | 1293 | |
d685c974 | 1294 | /* We could save TYPE in the chunk, but we don't use that for |
08cee789 DJ |
1295 | anything yet. If we wanted to, we could do it by adding it |
1296 | either before the beginning of the chunk or after its end, | |
1297 | and adjusting the size and pointer appropriately. */ | |
1298 | ||
1299 | /* We'll probably write to this after we return. */ | |
1300 | prefetchw (result); | |
b6f61163 DB |
1301 | |
1302 | #ifdef ENABLE_GC_CHECKING | |
b6f61163 | 1303 | /* `Poison' the entire allocated object. */ |
35dee980 | 1304 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (result, size)); |
b6f61163 | 1305 | memset (result, 0xaf, size); |
35dee980 HPN |
1306 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (result + orig_size, |
1307 | size - orig_size)); | |
b6f61163 DB |
1308 | #endif |
1309 | ||
1310 | /* Tell Valgrind that the memory is there, but its content isn't | |
1311 | defined. The bytes at the end of the object are still marked | |
1312 | unaccessible. */ | |
35dee980 | 1313 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (result, orig_size)); |
b6f61163 DB |
1314 | |
1315 | /* Keep track of how many bytes are being allocated. This | |
1316 | information is used in deciding when to collect. */ | |
b9bfca81 | 1317 | zone->allocated += size; |
b8698a0f | 1318 | |
76e20664 | 1319 | timevar_ggc_mem_total += size; |
b9bfca81 DJ |
1320 | |
1321 | #ifdef GATHER_STATISTICS | |
08cee789 | 1322 | ggc_record_overhead (orig_size, size - orig_size, result PASS_MEM_STAT); |
b9bfca81 DJ |
1323 | |
1324 | { | |
08cee789 | 1325 | size_t object_size = size; |
b9bfca81 DJ |
1326 | size_t overhead = object_size - orig_size; |
1327 | ||
1328 | zone->stats.total_overhead += overhead; | |
1329 | zone->stats.total_allocated += object_size; | |
1330 | ||
1331 | if (orig_size <= 32) | |
1332 | { | |
1333 | zone->stats.total_overhead_under32 += overhead; | |
1334 | zone->stats.total_allocated_under32 += object_size; | |
1335 | } | |
1336 | if (orig_size <= 64) | |
1337 | { | |
1338 | zone->stats.total_overhead_under64 += overhead; | |
1339 | zone->stats.total_allocated_under64 += object_size; | |
1340 | } | |
1341 | if (orig_size <= 128) | |
1342 | { | |
1343 | zone->stats.total_overhead_under128 += overhead; | |
1344 | zone->stats.total_allocated_under128 += object_size; | |
1345 | } | |
1346 | } | |
1347 | #endif | |
b6f61163 DB |
1348 | |
1349 | if (GGC_DEBUG_LEVEL >= 3) | |
08cee789 DJ |
1350 | fprintf (G.debug_file, "Allocating object, size=%lu at %p\n", |
1351 | (unsigned long) size, result); | |
b6f61163 DB |
1352 | |
1353 | return result; | |
1354 | } | |
1355 | ||
d91edf86 | 1356 | /* Allocate a SIZE of chunk memory of GTE type, into an appropriate zone |
b6f61163 DB |
1357 | for that type. */ |
1358 | ||
1359 | void * | |
92e838e2 PB |
1360 | ggc_alloc_typed_stat (enum gt_types_enum gte, size_t size |
1361 | MEM_STAT_DECL) | |
b6f61163 | 1362 | { |
47aeffac SB |
1363 | switch (gte) |
1364 | { | |
1365 | case gt_ggc_e_14lang_tree_node: | |
a6e4d85b | 1366 | return ggc_alloc_zone_pass_stat (size, &tree_zone); |
47aeffac SB |
1367 | |
1368 | case gt_ggc_e_7rtx_def: | |
a6e4d85b | 1369 | return ggc_alloc_zone_pass_stat (size, &rtl_zone); |
47aeffac SB |
1370 | |
1371 | case gt_ggc_e_9rtvec_def: | |
a6e4d85b | 1372 | return ggc_alloc_zone_pass_stat (size, &rtl_zone); |
47aeffac SB |
1373 | |
1374 | default: | |
a6e4d85b | 1375 | return ggc_alloc_zone_pass_stat (size, &main_zone); |
47aeffac | 1376 | } |
b6f61163 DB |
1377 | } |
1378 | ||
1379 | /* Normal ggc_alloc simply allocates into the main zone. */ | |
1380 | ||
1381 | void * | |
92e838e2 | 1382 | ggc_alloc_stat (size_t size MEM_STAT_DECL) |
b6f61163 | 1383 | { |
a6e4d85b | 1384 | return ggc_alloc_zone_pass_stat (size, &main_zone); |
b6f61163 DB |
1385 | } |
1386 | ||
9781b6da DB |
1387 | /* Poison the chunk. */ |
1388 | #ifdef ENABLE_GC_CHECKING | |
08cee789 DJ |
1389 | #define poison_region(PTR, SIZE) \ |
1390 | memset ((PTR), 0xa5, (SIZE)) | |
9781b6da | 1391 | #else |
08cee789 | 1392 | #define poison_region(PTR, SIZE) |
9781b6da DB |
1393 | #endif |
1394 | ||
1395 | /* Free the object at P. */ | |
1396 | ||
1397 | void | |
1398 | ggc_free (void *p) | |
1399 | { | |
08cee789 DJ |
1400 | struct page_entry *page; |
1401 | ||
1402 | #ifdef GATHER_STATISTICS | |
1403 | ggc_free_overhead (p); | |
1404 | #endif | |
1405 | ||
1406 | poison_region (p, ggc_get_size (p)); | |
1407 | ||
1408 | page = zone_get_object_page (p); | |
1409 | ||
1410 | if (page->large_p) | |
1411 | { | |
1412 | struct large_page_entry *large_page | |
1413 | = (struct large_page_entry *) page; | |
1414 | ||
1415 | /* Remove the page from the linked list. */ | |
1416 | if (large_page->prev) | |
1417 | large_page->prev->next = large_page->next; | |
1418 | else | |
1419 | { | |
1420 | gcc_assert (large_page->common.zone->large_pages == large_page); | |
1421 | large_page->common.zone->large_pages = large_page->next; | |
1422 | } | |
1423 | if (large_page->next) | |
1424 | large_page->next->prev = large_page->prev; | |
1425 | ||
1426 | large_page->common.zone->allocated -= large_page->bytes; | |
1427 | ||
1428 | /* Release the memory associated with this object. */ | |
1429 | free_large_page (large_page); | |
1430 | } | |
1431 | else if (page->pch_p) | |
1432 | /* Don't do anything. We won't allocate a new object from the | |
1433 | PCH zone so there's no point in releasing anything. */ | |
1434 | ; | |
1435 | else | |
1436 | { | |
1437 | size_t size = ggc_get_size (p); | |
1438 | ||
1439 | page->zone->allocated -= size; | |
1440 | ||
1441 | /* Add the chunk to the free list. We don't bother with coalescing, | |
1442 | since we are likely to want a chunk of this size again. */ | |
bf8e9c49 | 1443 | free_chunk ((char *)p, size, page->zone); |
08cee789 | 1444 | } |
9781b6da DB |
1445 | } |
1446 | ||
dae4174e TT |
1447 | /* Mark function for strings. */ |
1448 | ||
1449 | void | |
1450 | gt_ggc_m_S (const void *p) | |
1451 | { | |
1452 | page_entry *entry; | |
1453 | unsigned long offset; | |
1454 | ||
1455 | if (!p) | |
1456 | return; | |
1457 | ||
1458 | /* Look up the page on which the object is alloced. . */ | |
1459 | entry = lookup_page_table_if_allocated (p); | |
1460 | if (! entry) | |
1461 | return; | |
1462 | ||
1463 | if (entry->pch_p) | |
1464 | { | |
1465 | size_t alloc_word, alloc_bit, t; | |
1466 | t = ((const char *) p - pch_zone.page) / BYTES_PER_ALLOC_BIT; | |
1467 | alloc_word = t / (8 * sizeof (alloc_type)); | |
1468 | alloc_bit = t % (8 * sizeof (alloc_type)); | |
1469 | offset = zone_find_object_offset (pch_zone.alloc_bits, alloc_word, | |
1470 | alloc_bit); | |
1471 | } | |
1472 | else if (entry->large_p) | |
1473 | { | |
1474 | struct large_page_entry *le = (struct large_page_entry *) entry; | |
1475 | offset = ((const char *) p) - entry->page; | |
1476 | gcc_assert (offset < le->bytes); | |
1477 | } | |
1478 | else | |
1479 | { | |
1480 | struct small_page_entry *se = (struct small_page_entry *) entry; | |
1481 | unsigned int start_word = zone_get_object_alloc_word (p); | |
1482 | unsigned int start_bit = zone_get_object_alloc_bit (p); | |
1483 | offset = zone_find_object_offset (se->alloc_bits, start_word, start_bit); | |
1484 | ||
1485 | /* On some platforms a char* will not necessarily line up on an | |
1486 | allocation boundary, so we have to update the offset to | |
1487 | account for the leftover bytes. */ | |
1488 | offset += (size_t) p % BYTES_PER_ALLOC_BIT; | |
1489 | } | |
1490 | ||
1491 | if (offset) | |
1492 | { | |
1493 | /* Here we've seen a char* which does not point to the beginning | |
1494 | of an allocated object. We assume it points to the middle of | |
1495 | a STRING_CST. */ | |
1496 | gcc_assert (offset == offsetof (struct tree_string, str)); | |
1497 | p = ((const char *) p) - offset; | |
bf8e9c49 | 1498 | gt_ggc_mx_lang_tree_node (CONST_CAST(void *, p)); |
dae4174e TT |
1499 | return; |
1500 | } | |
1501 | ||
1502 | /* Inefficient, but also unlikely to matter. */ | |
1503 | ggc_set_mark (p); | |
1504 | } | |
1505 | ||
b6f61163 DB |
1506 | /* If P is not marked, mark it and return false. Otherwise return true. |
1507 | P must have been allocated by the GC allocator; it mustn't point to | |
1508 | static objects, stack variables, or memory allocated with malloc. */ | |
1509 | ||
1510 | int | |
1511 | ggc_set_mark (const void *p) | |
1512 | { | |
08cee789 DJ |
1513 | struct page_entry *page; |
1514 | const char *ptr = (const char *) p; | |
b6f61163 | 1515 | |
08cee789 DJ |
1516 | page = zone_get_object_page (p); |
1517 | ||
1518 | if (page->pch_p) | |
1519 | { | |
1520 | size_t mark_word, mark_bit, offset; | |
1521 | offset = (ptr - pch_zone.page) / BYTES_PER_MARK_BIT; | |
1522 | mark_word = offset / (8 * sizeof (mark_type)); | |
1523 | mark_bit = offset % (8 * sizeof (mark_type)); | |
b8698a0f | 1524 | |
08cee789 DJ |
1525 | if (pch_zone.mark_bits[mark_word] & (1 << mark_bit)) |
1526 | return 1; | |
1527 | pch_zone.mark_bits[mark_word] |= (1 << mark_bit); | |
1528 | } | |
1529 | else if (page->large_p) | |
1530 | { | |
1531 | struct large_page_entry *large_page | |
1532 | = (struct large_page_entry *) page; | |
1533 | ||
1534 | if (large_page->mark_p) | |
1535 | return 1; | |
1536 | large_page->mark_p = true; | |
1537 | } | |
1538 | else | |
1539 | { | |
1540 | struct small_page_entry *small_page | |
1541 | = (struct small_page_entry *) page; | |
1542 | ||
1543 | if (small_page->mark_bits[zone_get_object_mark_word (p)] | |
1544 | & (1 << zone_get_object_mark_bit (p))) | |
1545 | return 1; | |
1546 | small_page->mark_bits[zone_get_object_mark_word (p)] | |
1547 | |= (1 << zone_get_object_mark_bit (p)); | |
1548 | } | |
b6f61163 | 1549 | |
b6f61163 DB |
1550 | if (GGC_DEBUG_LEVEL >= 4) |
1551 | fprintf (G.debug_file, "Marking %p\n", p); | |
1552 | ||
1553 | return 0; | |
1554 | } | |
1555 | ||
1556 | /* Return 1 if P has been marked, zero otherwise. | |
1557 | P must have been allocated by the GC allocator; it mustn't point to | |
1558 | static objects, stack variables, or memory allocated with malloc. */ | |
1559 | ||
1560 | int | |
1561 | ggc_marked_p (const void *p) | |
1562 | { | |
08cee789 | 1563 | struct page_entry *page; |
bf8e9c49 | 1564 | const char *ptr = (const char *) p; |
b6f61163 | 1565 | |
08cee789 DJ |
1566 | page = zone_get_object_page (p); |
1567 | ||
1568 | if (page->pch_p) | |
1569 | { | |
1570 | size_t mark_word, mark_bit, offset; | |
1571 | offset = (ptr - pch_zone.page) / BYTES_PER_MARK_BIT; | |
1572 | mark_word = offset / (8 * sizeof (mark_type)); | |
1573 | mark_bit = offset % (8 * sizeof (mark_type)); | |
b8698a0f | 1574 | |
08cee789 DJ |
1575 | return (pch_zone.mark_bits[mark_word] & (1 << mark_bit)) != 0; |
1576 | } | |
1577 | ||
1578 | if (page->large_p) | |
1579 | { | |
1580 | struct large_page_entry *large_page | |
1581 | = (struct large_page_entry *) page; | |
1582 | ||
1583 | return large_page->mark_p; | |
1584 | } | |
1585 | else | |
1586 | { | |
1587 | struct small_page_entry *small_page | |
1588 | = (struct small_page_entry *) page; | |
1589 | ||
1590 | return 0 != (small_page->mark_bits[zone_get_object_mark_word (p)] | |
1591 | & (1 << zone_get_object_mark_bit (p))); | |
1592 | } | |
b6f61163 DB |
1593 | } |
1594 | ||
1595 | /* Return the size of the gc-able object P. */ | |
1596 | ||
1597 | size_t | |
1598 | ggc_get_size (const void *p) | |
1599 | { | |
08cee789 DJ |
1600 | struct page_entry *page; |
1601 | const char *ptr = (const char *) p; | |
b6f61163 | 1602 | |
08cee789 DJ |
1603 | page = zone_get_object_page (p); |
1604 | ||
1605 | if (page->pch_p) | |
1606 | { | |
1607 | size_t alloc_word, alloc_bit, offset, max_size; | |
1608 | offset = (ptr - pch_zone.page) / BYTES_PER_ALLOC_BIT + 1; | |
1609 | alloc_word = offset / (8 * sizeof (alloc_type)); | |
1610 | alloc_bit = offset % (8 * sizeof (alloc_type)); | |
1611 | max_size = pch_zone.bytes - (ptr - pch_zone.page); | |
1612 | return zone_object_size_1 (pch_zone.alloc_bits, alloc_word, alloc_bit, | |
1613 | max_size); | |
1614 | } | |
b6f61163 | 1615 | |
08cee789 DJ |
1616 | if (page->large_p) |
1617 | return ((struct large_page_entry *)page)->bytes; | |
1618 | else | |
1619 | return zone_find_object_size ((struct small_page_entry *) page, p); | |
b6f61163 DB |
1620 | } |
1621 | ||
1622 | /* Initialize the ggc-zone-mmap allocator. */ | |
1623 | void | |
578e8170 | 1624 | init_ggc (void) |
b6f61163 | 1625 | { |
08cee789 DJ |
1626 | /* The allocation size must be greater than BYTES_PER_MARK_BIT, and |
1627 | a multiple of both BYTES_PER_ALLOC_BIT and FREE_BIN_DELTA, for | |
1628 | the current assumptions to hold. */ | |
1629 | ||
1630 | gcc_assert (FREE_BIN_DELTA == MAX_ALIGNMENT); | |
1631 | ||
47aeffac | 1632 | /* Set up the main zone by hand. */ |
b6f61163 DB |
1633 | main_zone.name = "Main zone"; |
1634 | G.zones = &main_zone; | |
1635 | ||
47aeffac | 1636 | /* Allocate the default zones. */ |
08cee789 DJ |
1637 | new_ggc_zone_1 (&rtl_zone, "RTL zone"); |
1638 | new_ggc_zone_1 (&tree_zone, "Tree zone"); | |
1639 | new_ggc_zone_1 (&tree_id_zone, "Tree identifier zone"); | |
b6f61163 DB |
1640 | |
1641 | G.pagesize = getpagesize(); | |
1642 | G.lg_pagesize = exact_log2 (G.pagesize); | |
08cee789 DJ |
1643 | G.page_mask = ~(G.pagesize - 1); |
1644 | ||
1645 | /* Require the system page size to be a multiple of GGC_PAGE_SIZE. */ | |
1646 | gcc_assert ((G.pagesize & (GGC_PAGE_SIZE - 1)) == 0); | |
1647 | ||
1648 | /* Allocate 16 system pages at a time. */ | |
1649 | G.quire_size = 16 * G.pagesize / GGC_PAGE_SIZE; | |
1650 | ||
1651 | /* Calculate the size of the allocation bitmap and other overhead. */ | |
1652 | /* Right now we allocate bits for the page header and bitmap. These | |
1653 | are wasted, but a little tricky to eliminate. */ | |
1654 | G.small_page_overhead | |
1655 | = PAGE_OVERHEAD + (GGC_PAGE_SIZE / BYTES_PER_ALLOC_BIT / 8); | |
1656 | /* G.small_page_overhead = ROUND_UP (G.small_page_overhead, MAX_ALIGNMENT); */ | |
1657 | ||
b6f61163 DB |
1658 | #ifdef HAVE_MMAP_DEV_ZERO |
1659 | G.dev_zero_fd = open ("/dev/zero", O_RDONLY); | |
282899df | 1660 | gcc_assert (G.dev_zero_fd != -1); |
b6f61163 DB |
1661 | #endif |
1662 | ||
1663 | #if 0 | |
1664 | G.debug_file = fopen ("ggc-mmap.debug", "w"); | |
1665 | setlinebuf (G.debug_file); | |
1666 | #else | |
1667 | G.debug_file = stdout; | |
1668 | #endif | |
1669 | ||
1670 | #ifdef USING_MMAP | |
1671 | /* StunOS has an amazing off-by-one error for the first mmap allocation | |
1672 | after fiddling with RLIMIT_STACK. The result, as hard as it is to | |
1673 | believe, is an unaligned page allocation, which would cause us to | |
1674 | hork badly if we tried to use it. */ | |
1675 | { | |
1676 | char *p = alloc_anon (NULL, G.pagesize, &main_zone); | |
08cee789 | 1677 | struct small_page_entry *e; |
b6f61163 DB |
1678 | if ((size_t)p & (G.pagesize - 1)) |
1679 | { | |
1680 | /* How losing. Discard this one and try another. If we still | |
1681 | can't get something useful, give up. */ | |
1682 | ||
1683 | p = alloc_anon (NULL, G.pagesize, &main_zone); | |
282899df | 1684 | gcc_assert (!((size_t)p & (G.pagesize - 1))); |
b6f61163 DB |
1685 | } |
1686 | ||
08cee789 DJ |
1687 | if (GGC_PAGE_SIZE == G.pagesize) |
1688 | { | |
1689 | /* We have a good page, might as well hold onto it... */ | |
bf8e9c49 | 1690 | e = XCNEWVAR (struct small_page_entry, G.small_page_overhead); |
08cee789 DJ |
1691 | e->common.page = p; |
1692 | e->common.zone = &main_zone; | |
1693 | e->next = main_zone.free_pages; | |
1694 | set_page_table_entry (e->common.page, &e->common); | |
1695 | main_zone.free_pages = e; | |
1696 | } | |
1697 | else | |
1698 | { | |
1699 | munmap (p, G.pagesize); | |
1700 | } | |
b6f61163 DB |
1701 | } |
1702 | #endif | |
1703 | } | |
1704 | ||
47aeffac SB |
1705 | /* Start a new GGC zone. */ |
1706 | ||
08cee789 DJ |
1707 | static void |
1708 | new_ggc_zone_1 (struct alloc_zone *new_zone, const char * name) | |
47aeffac | 1709 | { |
47aeffac SB |
1710 | new_zone->name = name; |
1711 | new_zone->next_zone = G.zones->next_zone; | |
1712 | G.zones->next_zone = new_zone; | |
08cee789 DJ |
1713 | } |
1714 | ||
1715 | struct alloc_zone * | |
1716 | new_ggc_zone (const char * name) | |
1717 | { | |
bf8e9c49 | 1718 | struct alloc_zone *new_zone = XCNEW (struct alloc_zone); |
08cee789 | 1719 | new_ggc_zone_1 (new_zone, name); |
47aeffac SB |
1720 | return new_zone; |
1721 | } | |
1722 | ||
1723 | /* Destroy a GGC zone. */ | |
1724 | void | |
1725 | destroy_ggc_zone (struct alloc_zone * dead_zone) | |
1726 | { | |
1727 | struct alloc_zone *z; | |
1728 | ||
1729 | for (z = G.zones; z && z->next_zone != dead_zone; z = z->next_zone) | |
282899df NS |
1730 | /* Just find that zone. */ |
1731 | continue; | |
47aeffac | 1732 | |
b944d187 | 1733 | /* We should have found the zone in the list. Anything else is fatal. */ |
282899df | 1734 | gcc_assert (z); |
47aeffac | 1735 | |
b944d187 | 1736 | /* z is dead, baby. z is dead. */ |
08cee789 | 1737 | z->dead = true; |
b6f61163 | 1738 | } |
b6f61163 DB |
1739 | |
1740 | /* Free all empty pages and objects within a page for a given zone */ | |
1741 | ||
1742 | static void | |
1743 | sweep_pages (struct alloc_zone *zone) | |
1744 | { | |
08cee789 DJ |
1745 | struct large_page_entry **lpp, *lp, *lnext; |
1746 | struct small_page_entry **spp, *sp, *snext; | |
1747 | char *last_free; | |
1748 | size_t allocated = 0; | |
02fef853 | 1749 | bool nomarksinpage; |
08cee789 | 1750 | |
b6f61163 DB |
1751 | /* First, reset the free_chunks lists, since we are going to |
1752 | re-free free chunks in hopes of coalescing them into large chunks. */ | |
1753 | memset (zone->free_chunks, 0, sizeof (zone->free_chunks)); | |
08cee789 DJ |
1754 | zone->high_free_bin = 0; |
1755 | zone->cached_free = NULL; | |
1756 | zone->cached_free_size = 0; | |
1757 | ||
1758 | /* Large pages are all or none affairs. Either they are completely | |
1759 | empty, or they are completely full. */ | |
1760 | lpp = &zone->large_pages; | |
1761 | for (lp = zone->large_pages; lp != NULL; lp = lnext) | |
b6f61163 | 1762 | { |
08cee789 DJ |
1763 | gcc_assert (lp->common.large_p); |
1764 | ||
1765 | lnext = lp->next; | |
1766 | ||
1767 | #ifdef GATHER_STATISTICS | |
1768 | /* This page has now survived another collection. */ | |
1769 | lp->common.survived++; | |
1770 | #endif | |
1771 | ||
1772 | if (lp->mark_p) | |
b6f61163 | 1773 | { |
08cee789 DJ |
1774 | lp->mark_p = false; |
1775 | allocated += lp->bytes; | |
1776 | lpp = &lp->next; | |
1777 | } | |
1778 | else | |
1779 | { | |
1780 | *lpp = lnext; | |
b6f61163 | 1781 | #ifdef ENABLE_GC_CHECKING |
08cee789 DJ |
1782 | /* Poison the page. */ |
1783 | memset (lp->common.page, 0xb5, SMALL_PAGE_SIZE); | |
b6f61163 | 1784 | #endif |
08cee789 DJ |
1785 | if (lp->prev) |
1786 | lp->prev->next = lp->next; | |
1787 | if (lp->next) | |
1788 | lp->next->prev = lp->prev; | |
1789 | free_large_page (lp); | |
b6f61163 | 1790 | } |
08cee789 DJ |
1791 | } |
1792 | ||
1793 | spp = &zone->pages; | |
1794 | for (sp = zone->pages; sp != NULL; sp = snext) | |
1795 | { | |
1796 | char *object, *last_object; | |
1797 | char *end; | |
1798 | alloc_type *alloc_word_p; | |
1799 | mark_type *mark_word_p; | |
1800 | ||
1801 | gcc_assert (!sp->common.large_p); | |
b6f61163 | 1802 | |
08cee789 DJ |
1803 | snext = sp->next; |
1804 | ||
1805 | #ifdef GATHER_STATISTICS | |
b6f61163 | 1806 | /* This page has now survived another collection. */ |
08cee789 DJ |
1807 | sp->common.survived++; |
1808 | #endif | |
b6f61163 | 1809 | |
08cee789 DJ |
1810 | /* Step through all chunks, consolidate those that are free and |
1811 | insert them into the free lists. Note that consolidation | |
1812 | slows down collection slightly. */ | |
b6f61163 | 1813 | |
08cee789 DJ |
1814 | last_object = object = sp->common.page; |
1815 | end = sp->common.page + SMALL_PAGE_SIZE; | |
b6f61163 | 1816 | last_free = NULL; |
02fef853 | 1817 | nomarksinpage = true; |
08cee789 DJ |
1818 | mark_word_p = sp->mark_bits; |
1819 | alloc_word_p = sp->alloc_bits; | |
1820 | ||
1821 | gcc_assert (BYTES_PER_ALLOC_BIT == BYTES_PER_MARK_BIT); | |
1822 | ||
1823 | object = sp->common.page; | |
b6f61163 DB |
1824 | do |
1825 | { | |
08cee789 DJ |
1826 | unsigned int i, n; |
1827 | alloc_type alloc_word; | |
1828 | mark_type mark_word; | |
1829 | ||
1830 | alloc_word = *alloc_word_p++; | |
1831 | mark_word = *mark_word_p++; | |
1832 | ||
1833 | if (mark_word) | |
1834 | nomarksinpage = false; | |
1835 | ||
1836 | /* There ought to be some way to do this without looping... */ | |
1837 | i = 0; | |
1838 | while ((n = alloc_ffs (alloc_word)) != 0) | |
b6f61163 | 1839 | { |
08cee789 DJ |
1840 | /* Extend the current state for n - 1 bits. We can't |
1841 | shift alloc_word by n, even though it isn't used in the | |
1842 | loop, in case only the highest bit was set. */ | |
1843 | alloc_word >>= n - 1; | |
1844 | mark_word >>= n - 1; | |
1845 | object += BYTES_PER_MARK_BIT * (n - 1); | |
1846 | ||
1847 | if (mark_word & 1) | |
b6f61163 | 1848 | { |
08cee789 DJ |
1849 | if (last_free) |
1850 | { | |
35dee980 HPN |
1851 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (last_free, |
1852 | object | |
1853 | - last_free)); | |
08cee789 DJ |
1854 | poison_region (last_free, object - last_free); |
1855 | free_chunk (last_free, object - last_free, zone); | |
1856 | last_free = NULL; | |
1857 | } | |
1858 | else | |
1859 | allocated += object - last_object; | |
1860 | last_object = object; | |
b6f61163 DB |
1861 | } |
1862 | else | |
1863 | { | |
08cee789 DJ |
1864 | if (last_free == NULL) |
1865 | { | |
1866 | last_free = object; | |
1867 | allocated += object - last_object; | |
1868 | } | |
1869 | else | |
1870 | zone_clear_object_alloc_bit (sp, object); | |
b6f61163 | 1871 | } |
08cee789 DJ |
1872 | |
1873 | /* Shift to just after the alloc bit we handled. */ | |
1874 | alloc_word >>= 1; | |
1875 | mark_word >>= 1; | |
1876 | object += BYTES_PER_MARK_BIT; | |
1877 | ||
1878 | i += n; | |
b6f61163 DB |
1879 | } |
1880 | ||
08cee789 | 1881 | object += BYTES_PER_MARK_BIT * (8 * sizeof (alloc_type) - i); |
b6f61163 | 1882 | } |
08cee789 | 1883 | while (object < end); |
b6f61163 | 1884 | |
02fef853 DB |
1885 | if (nomarksinpage) |
1886 | { | |
08cee789 | 1887 | *spp = snext; |
02fef853 | 1888 | #ifdef ENABLE_GC_CHECKING |
35dee980 HPN |
1889 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (sp->common.page, |
1890 | SMALL_PAGE_SIZE)); | |
02fef853 | 1891 | /* Poison the page. */ |
08cee789 | 1892 | memset (sp->common.page, 0xb5, SMALL_PAGE_SIZE); |
02fef853 | 1893 | #endif |
08cee789 | 1894 | free_small_page (sp); |
02fef853 DB |
1895 | continue; |
1896 | } | |
1897 | else if (last_free) | |
b6f61163 | 1898 | { |
35dee980 HPN |
1899 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (last_free, |
1900 | object - last_free)); | |
08cee789 DJ |
1901 | poison_region (last_free, object - last_free); |
1902 | free_chunk (last_free, object - last_free, zone); | |
b6f61163 | 1903 | } |
08cee789 DJ |
1904 | else |
1905 | allocated += object - last_object; | |
1906 | ||
1907 | spp = &sp->next; | |
b6f61163 DB |
1908 | } |
1909 | ||
1910 | zone->allocated = allocated; | |
1911 | } | |
1912 | ||
1913 | /* mark-and-sweep routine for collecting a single zone. NEED_MARKING | |
1914 | is true if we need to mark before sweeping, false if some other | |
1915 | zone collection has already performed marking for us. Returns true | |
1916 | if we collected, false otherwise. */ | |
1917 | ||
1918 | static bool | |
1919 | ggc_collect_1 (struct alloc_zone *zone, bool need_marking) | |
1920 | { | |
08cee789 DJ |
1921 | #if 0 |
1922 | /* */ | |
1923 | { | |
1924 | int i; | |
1925 | for (i = 0; i < NUM_FREE_BINS + 1; i++) | |
1926 | { | |
1927 | struct alloc_chunk *chunk; | |
1928 | int n, tot; | |
1929 | ||
1930 | n = 0; | |
1931 | tot = 0; | |
1932 | chunk = zone->free_chunks[i]; | |
1933 | while (chunk) | |
1934 | { | |
1935 | n++; | |
1936 | tot += chunk->size; | |
1937 | chunk = chunk->next_free; | |
1938 | } | |
1939 | fprintf (stderr, "Bin %d: %d free chunks (%d bytes)\n", | |
1940 | i, n, tot); | |
1941 | } | |
1942 | } | |
1943 | /* */ | |
1944 | #endif | |
1945 | ||
b6f61163 | 1946 | if (!quiet_flag) |
b944d187 SB |
1947 | fprintf (stderr, " {%s GC %luk -> ", |
1948 | zone->name, (unsigned long) zone->allocated / 1024); | |
b6f61163 DB |
1949 | |
1950 | /* Zero the total allocated bytes. This will be recalculated in the | |
1951 | sweep phase. */ | |
1952 | zone->allocated = 0; | |
1953 | ||
1954 | /* Release the pages we freed the last time we collected, but didn't | |
1955 | reuse in the interim. */ | |
1956 | release_pages (zone); | |
1957 | ||
b6f61163 | 1958 | if (need_marking) |
08cee789 DJ |
1959 | { |
1960 | zone_allocate_marks (); | |
1961 | ggc_mark_roots (); | |
1962 | #ifdef GATHER_STATISTICS | |
1963 | ggc_prune_overhead_list (); | |
1964 | #endif | |
1965 | } | |
b8698a0f | 1966 | |
b6f61163 DB |
1967 | sweep_pages (zone); |
1968 | zone->was_collected = true; | |
1969 | zone->allocated_last_gc = zone->allocated; | |
1970 | ||
b6f61163 DB |
1971 | if (!quiet_flag) |
1972 | fprintf (stderr, "%luk}", (unsigned long) zone->allocated / 1024); | |
1973 | return true; | |
1974 | } | |
1975 | ||
08cee789 | 1976 | #ifdef GATHER_STATISTICS |
b6f61163 DB |
1977 | /* Calculate the average page survival rate in terms of number of |
1978 | collections. */ | |
1979 | ||
1980 | static float | |
1981 | calculate_average_page_survival (struct alloc_zone *zone) | |
1982 | { | |
1983 | float count = 0.0; | |
1984 | float survival = 0.0; | |
08cee789 DJ |
1985 | struct small_page_entry *p; |
1986 | struct large_page_entry *lp; | |
b6f61163 DB |
1987 | for (p = zone->pages; p; p = p->next) |
1988 | { | |
1989 | count += 1.0; | |
08cee789 | 1990 | survival += p->common.survived; |
b6f61163 | 1991 | } |
08cee789 | 1992 | for (lp = zone->large_pages; lp; lp = lp->next) |
b6f61163 | 1993 | { |
08cee789 DJ |
1994 | count += 1.0; |
1995 | survival += lp->common.survived; | |
b6f61163 | 1996 | } |
08cee789 | 1997 | return survival/count; |
b6f61163 | 1998 | } |
08cee789 DJ |
1999 | #endif |
2000 | ||
b6f61163 DB |
2001 | /* Top level collection routine. */ |
2002 | ||
2003 | void | |
578e8170 | 2004 | ggc_collect (void) |
b6f61163 DB |
2005 | { |
2006 | struct alloc_zone *zone; | |
2007 | bool marked = false; | |
b6f61163 DB |
2008 | |
2009 | timevar_push (TV_GC); | |
b9bfca81 | 2010 | |
08cee789 | 2011 | if (!ggc_force_collect) |
b9bfca81 DJ |
2012 | { |
2013 | float allocated_last_gc = 0, allocated = 0, min_expand; | |
2014 | ||
2015 | for (zone = G.zones; zone; zone = zone->next_zone) | |
2016 | { | |
2017 | allocated_last_gc += zone->allocated_last_gc; | |
2018 | allocated += zone->allocated; | |
2019 | } | |
2020 | ||
2021 | allocated_last_gc = | |
2022 | MAX (allocated_last_gc, | |
2023 | (size_t) PARAM_VALUE (GGC_MIN_HEAPSIZE) * 1024); | |
2024 | min_expand = allocated_last_gc * PARAM_VALUE (GGC_MIN_EXPAND) / 100; | |
2025 | ||
2026 | if (allocated < allocated_last_gc + min_expand) | |
2027 | { | |
2028 | timevar_pop (TV_GC); | |
2029 | return; | |
2030 | } | |
2031 | } | |
2032 | ||
ae2392a9 BS |
2033 | invoke_plugin_callbacks (PLUGIN_GGC_START, NULL); |
2034 | ||
b6f61163 DB |
2035 | /* Start by possibly collecting the main zone. */ |
2036 | main_zone.was_collected = false; | |
2037 | marked |= ggc_collect_1 (&main_zone, true); | |
47aeffac | 2038 | |
b6f61163 DB |
2039 | /* In order to keep the number of collections down, we don't |
2040 | collect other zones unless we are collecting the main zone. This | |
2041 | gives us roughly the same number of collections as we used to | |
2042 | have with the old gc. The number of collection is important | |
2043 | because our main slowdown (according to profiling) is now in | |
2044 | marking. So if we mark twice as often as we used to, we'll be | |
2045 | twice as slow. Hopefully we'll avoid this cost when we mark | |
2046 | zone-at-a-time. */ | |
b9bfca81 DJ |
2047 | /* NOTE drow/2004-07-28: We now always collect the main zone, but |
2048 | keep this code in case the heuristics are further refined. */ | |
b6f61163 DB |
2049 | |
2050 | if (main_zone.was_collected) | |
2051 | { | |
47aeffac SB |
2052 | struct alloc_zone *zone; |
2053 | ||
2054 | for (zone = main_zone.next_zone; zone; zone = zone->next_zone) | |
2055 | { | |
47aeffac SB |
2056 | zone->was_collected = false; |
2057 | marked |= ggc_collect_1 (zone, !marked); | |
2058 | } | |
b6f61163 DB |
2059 | } |
2060 | ||
08cee789 | 2061 | #ifdef GATHER_STATISTICS |
b6f61163 DB |
2062 | /* Print page survival stats, if someone wants them. */ |
2063 | if (GGC_DEBUG_LEVEL >= 2) | |
2064 | { | |
47aeffac | 2065 | for (zone = G.zones; zone; zone = zone->next_zone) |
b6f61163 | 2066 | { |
47aeffac SB |
2067 | if (zone->was_collected) |
2068 | { | |
08cee789 | 2069 | float f = calculate_average_page_survival (zone); |
47aeffac SB |
2070 | printf ("Average page survival in zone `%s' is %f\n", |
2071 | zone->name, f); | |
2072 | } | |
b6f61163 DB |
2073 | } |
2074 | } | |
08cee789 | 2075 | #endif |
47aeffac | 2076 | |
b6f61163 | 2077 | if (marked) |
08cee789 | 2078 | zone_free_marks (); |
b944d187 SB |
2079 | |
2080 | /* Free dead zones. */ | |
2081 | for (zone = G.zones; zone && zone->next_zone; zone = zone->next_zone) | |
2082 | { | |
2083 | if (zone->next_zone->dead) | |
2084 | { | |
2085 | struct alloc_zone *dead_zone = zone->next_zone; | |
2086 | ||
2087 | printf ("Zone `%s' is dead and will be freed.\n", dead_zone->name); | |
2088 | ||
2089 | /* The zone must be empty. */ | |
282899df | 2090 | gcc_assert (!dead_zone->allocated); |
b944d187 SB |
2091 | |
2092 | /* Unchain the dead zone, release all its pages and free it. */ | |
2093 | zone->next_zone = zone->next_zone->next_zone; | |
2094 | release_pages (dead_zone); | |
2095 | free (dead_zone); | |
2096 | } | |
2097 | } | |
2098 | ||
ae2392a9 BS |
2099 | invoke_plugin_callbacks (PLUGIN_GGC_END, NULL); |
2100 | ||
b6f61163 DB |
2101 | timevar_pop (TV_GC); |
2102 | } | |
2103 | ||
2104 | /* Print allocation statistics. */ | |
b9bfca81 DJ |
2105 | #define SCALE(x) ((unsigned long) ((x) < 1024*10 \ |
2106 | ? (x) \ | |
2107 | : ((x) < 1024*1024*10 \ | |
2108 | ? (x) / 1024 \ | |
2109 | : (x) / (1024*1024)))) | |
2110 | #define LABEL(x) ((x) < 1024*10 ? ' ' : ((x) < 1024*1024*10 ? 'k' : 'M')) | |
b6f61163 DB |
2111 | |
2112 | void | |
578e8170 | 2113 | ggc_print_statistics (void) |
b6f61163 | 2114 | { |
b9bfca81 DJ |
2115 | struct alloc_zone *zone; |
2116 | struct ggc_statistics stats; | |
2117 | size_t total_overhead = 0, total_allocated = 0, total_bytes_mapped = 0; | |
08cee789 | 2118 | size_t pte_overhead, i; |
b9bfca81 DJ |
2119 | |
2120 | /* Clear the statistics. */ | |
2121 | memset (&stats, 0, sizeof (stats)); | |
2122 | ||
08cee789 DJ |
2123 | /* Make sure collection will really occur. */ |
2124 | ggc_force_collect = true; | |
b9bfca81 DJ |
2125 | |
2126 | /* Collect and print the statistics common across collectors. */ | |
2127 | ggc_print_common_statistics (stderr, &stats); | |
2128 | ||
08cee789 | 2129 | ggc_force_collect = false; |
b9bfca81 DJ |
2130 | |
2131 | /* Release free pages so that we will not count the bytes allocated | |
2132 | there as part of the total allocated memory. */ | |
2133 | for (zone = G.zones; zone; zone = zone->next_zone) | |
2134 | release_pages (zone); | |
2135 | ||
2136 | /* Collect some information about the various sizes of | |
2137 | allocation. */ | |
2138 | fprintf (stderr, | |
2139 | "Memory still allocated at the end of the compilation process\n"); | |
2140 | ||
2141 | fprintf (stderr, "%20s %10s %10s %10s\n", | |
2142 | "Zone", "Allocated", "Used", "Overhead"); | |
2143 | for (zone = G.zones; zone; zone = zone->next_zone) | |
2144 | { | |
08cee789 DJ |
2145 | struct large_page_entry *large_page; |
2146 | size_t overhead, allocated, in_use; | |
b9bfca81 | 2147 | |
08cee789 DJ |
2148 | /* Skip empty zones. */ |
2149 | if (!zone->pages && !zone->large_pages) | |
b9bfca81 DJ |
2150 | continue; |
2151 | ||
08cee789 | 2152 | allocated = in_use = 0; |
b9bfca81 | 2153 | |
08cee789 DJ |
2154 | overhead = sizeof (struct alloc_zone); |
2155 | ||
2156 | for (large_page = zone->large_pages; large_page != NULL; | |
2157 | large_page = large_page->next) | |
b9bfca81 | 2158 | { |
08cee789 DJ |
2159 | allocated += large_page->bytes; |
2160 | in_use += large_page->bytes; | |
2161 | overhead += sizeof (struct large_page_entry); | |
2162 | } | |
b9bfca81 | 2163 | |
08cee789 DJ |
2164 | /* There's no easy way to walk through the small pages finding |
2165 | used and unused objects. Instead, add all the pages, and | |
2166 | subtract out the free list. */ | |
b9bfca81 | 2167 | |
08cee789 DJ |
2168 | allocated += GGC_PAGE_SIZE * zone->n_small_pages; |
2169 | in_use += GGC_PAGE_SIZE * zone->n_small_pages; | |
2170 | overhead += G.small_page_overhead * zone->n_small_pages; | |
b9bfca81 | 2171 | |
08cee789 DJ |
2172 | for (i = 0; i <= NUM_FREE_BINS; i++) |
2173 | { | |
2174 | struct alloc_chunk *chunk = zone->free_chunks[i]; | |
2175 | while (chunk) | |
b9bfca81 | 2176 | { |
08cee789 DJ |
2177 | in_use -= ggc_get_size (chunk); |
2178 | chunk = chunk->next_free; | |
b9bfca81 DJ |
2179 | } |
2180 | } | |
b8698a0f | 2181 | |
b9bfca81 DJ |
2182 | fprintf (stderr, "%20s %10lu%c %10lu%c %10lu%c\n", |
2183 | zone->name, | |
2184 | SCALE (allocated), LABEL (allocated), | |
2185 | SCALE (in_use), LABEL (in_use), | |
2186 | SCALE (overhead), LABEL (overhead)); | |
2187 | ||
282899df | 2188 | gcc_assert (in_use == zone->allocated); |
b9bfca81 DJ |
2189 | |
2190 | total_overhead += overhead; | |
2191 | total_allocated += zone->allocated; | |
2192 | total_bytes_mapped += zone->bytes_mapped; | |
2193 | } | |
2194 | ||
08cee789 DJ |
2195 | /* Count the size of the page table as best we can. */ |
2196 | #if HOST_BITS_PER_PTR <= 32 | |
2197 | pte_overhead = sizeof (G.lookup); | |
2198 | for (i = 0; i < PAGE_L1_SIZE; i++) | |
2199 | if (G.lookup[i]) | |
2200 | pte_overhead += PAGE_L2_SIZE * sizeof (struct page_entry *); | |
2201 | #else | |
2202 | { | |
76e20664 | 2203 | page_table table = G.lookup; |
08cee789 DJ |
2204 | pte_overhead = 0; |
2205 | while (table) | |
2206 | { | |
2207 | pte_overhead += sizeof (*table); | |
2208 | for (i = 0; i < PAGE_L1_SIZE; i++) | |
2209 | if (table->table[i]) | |
2210 | pte_overhead += PAGE_L2_SIZE * sizeof (struct page_entry *); | |
2211 | table = table->next; | |
2212 | } | |
2213 | } | |
2214 | #endif | |
2215 | fprintf (stderr, "%20s %11s %11s %10lu%c\n", "Page Table", | |
2216 | "", "", SCALE (pte_overhead), LABEL (pte_overhead)); | |
2217 | total_overhead += pte_overhead; | |
2218 | ||
b9bfca81 DJ |
2219 | fprintf (stderr, "%20s %10lu%c %10lu%c %10lu%c\n", "Total", |
2220 | SCALE (total_bytes_mapped), LABEL (total_bytes_mapped), | |
2221 | SCALE (total_allocated), LABEL(total_allocated), | |
2222 | SCALE (total_overhead), LABEL (total_overhead)); | |
2223 | ||
b8698a0f | 2224 | #ifdef GATHER_STATISTICS |
b9bfca81 DJ |
2225 | { |
2226 | unsigned long long all_overhead = 0, all_allocated = 0; | |
2227 | unsigned long long all_overhead_under32 = 0, all_allocated_under32 = 0; | |
2228 | unsigned long long all_overhead_under64 = 0, all_allocated_under64 = 0; | |
2229 | unsigned long long all_overhead_under128 = 0, all_allocated_under128 = 0; | |
2230 | ||
2231 | fprintf (stderr, "\nTotal allocations and overheads during the compilation process\n"); | |
2232 | ||
2233 | for (zone = G.zones; zone; zone = zone->next_zone) | |
2234 | { | |
2235 | all_overhead += zone->stats.total_overhead; | |
2236 | all_allocated += zone->stats.total_allocated; | |
2237 | ||
2238 | all_allocated_under32 += zone->stats.total_allocated_under32; | |
2239 | all_overhead_under32 += zone->stats.total_overhead_under32; | |
2240 | ||
2241 | all_allocated_under64 += zone->stats.total_allocated_under64; | |
2242 | all_overhead_under64 += zone->stats.total_overhead_under64; | |
b8698a0f | 2243 | |
b9bfca81 DJ |
2244 | all_allocated_under128 += zone->stats.total_allocated_under128; |
2245 | all_overhead_under128 += zone->stats.total_overhead_under128; | |
2246 | ||
2247 | fprintf (stderr, "%20s: %10lld\n", | |
2248 | zone->name, zone->stats.total_allocated); | |
2249 | } | |
2250 | ||
2251 | fprintf (stderr, "\n"); | |
2252 | ||
2253 | fprintf (stderr, "Total Overhead: %10lld\n", | |
2254 | all_overhead); | |
2255 | fprintf (stderr, "Total Allocated: %10lld\n", | |
2256 | all_allocated); | |
2257 | ||
2258 | fprintf (stderr, "Total Overhead under 32B: %10lld\n", | |
2259 | all_overhead_under32); | |
2260 | fprintf (stderr, "Total Allocated under 32B: %10lld\n", | |
2261 | all_allocated_under32); | |
2262 | fprintf (stderr, "Total Overhead under 64B: %10lld\n", | |
2263 | all_overhead_under64); | |
2264 | fprintf (stderr, "Total Allocated under 64B: %10lld\n", | |
2265 | all_allocated_under64); | |
2266 | fprintf (stderr, "Total Overhead under 128B: %10lld\n", | |
2267 | all_overhead_under128); | |
2268 | fprintf (stderr, "Total Allocated under 128B: %10lld\n", | |
2269 | all_allocated_under128); | |
2270 | } | |
2271 | #endif | |
b6f61163 DB |
2272 | } |
2273 | ||
08cee789 DJ |
2274 | /* Precompiled header support. */ |
2275 | ||
2276 | /* For precompiled headers, we sort objects based on their type. We | |
2277 | also sort various objects into their own buckets; currently this | |
2278 | covers strings and IDENTIFIER_NODE trees. The choices of how | |
2279 | to sort buckets have not yet been tuned. */ | |
2280 | ||
2281 | #define NUM_PCH_BUCKETS (gt_types_enum_last + 3) | |
2282 | ||
2283 | #define OTHER_BUCKET (gt_types_enum_last + 0) | |
2284 | #define IDENTIFIER_BUCKET (gt_types_enum_last + 1) | |
2285 | #define STRING_BUCKET (gt_types_enum_last + 2) | |
2286 | ||
2287 | struct ggc_pch_ondisk | |
2288 | { | |
2289 | size_t total; | |
2290 | size_t type_totals[NUM_PCH_BUCKETS]; | |
2291 | }; | |
2292 | ||
b6f61163 DB |
2293 | struct ggc_pch_data |
2294 | { | |
08cee789 | 2295 | struct ggc_pch_ondisk d; |
b6f61163 | 2296 | size_t base; |
08cee789 DJ |
2297 | size_t orig_base; |
2298 | size_t alloc_size; | |
2299 | alloc_type *alloc_bits; | |
2300 | size_t type_bases[NUM_PCH_BUCKETS]; | |
2301 | size_t start_offset; | |
b6f61163 DB |
2302 | }; |
2303 | ||
1ae58c30 | 2304 | /* Initialize the PCH data structure. */ |
b6f61163 DB |
2305 | |
2306 | struct ggc_pch_data * | |
2307 | init_ggc_pch (void) | |
2308 | { | |
bf8e9c49 | 2309 | return XCNEW (struct ggc_pch_data); |
b6f61163 DB |
2310 | } |
2311 | ||
08cee789 DJ |
2312 | /* Return which of the page-aligned buckets the object at X, with type |
2313 | TYPE, should be sorted into in the PCH. Strings will have | |
2314 | IS_STRING set and TYPE will be gt_types_enum_last. Other objects | |
2315 | of unknown type will also have TYPE equal to gt_types_enum_last. */ | |
2316 | ||
2317 | static int | |
2318 | pch_bucket (void *x, enum gt_types_enum type, | |
2319 | bool is_string) | |
2320 | { | |
2321 | /* Sort identifiers into their own bucket, to improve locality | |
2322 | when searching the identifier hash table. */ | |
2323 | if (type == gt_ggc_e_14lang_tree_node | |
2324 | && TREE_CODE ((tree) x) == IDENTIFIER_NODE) | |
2325 | return IDENTIFIER_BUCKET; | |
2326 | else if (type == gt_types_enum_last) | |
2327 | { | |
2328 | if (is_string) | |
2329 | return STRING_BUCKET; | |
2330 | return OTHER_BUCKET; | |
2331 | } | |
2332 | return type; | |
2333 | } | |
2334 | ||
b6f61163 DB |
2335 | /* Add the size of object X to the size of the PCH data. */ |
2336 | ||
2337 | void | |
2338 | ggc_pch_count_object (struct ggc_pch_data *d, void *x ATTRIBUTE_UNUSED, | |
08cee789 | 2339 | size_t size, bool is_string, enum gt_types_enum type) |
b6f61163 | 2340 | { |
08cee789 DJ |
2341 | /* NOTE: Right now we don't need to align up the size of any objects. |
2342 | Strings can be unaligned, and everything else is allocated to a | |
2343 | MAX_ALIGNMENT boundary already. */ | |
2344 | ||
2345 | d->d.type_totals[pch_bucket (x, type, is_string)] += size; | |
b6f61163 DB |
2346 | } |
2347 | ||
2348 | /* Return the total size of the PCH data. */ | |
2349 | ||
2350 | size_t | |
2351 | ggc_pch_total_size (struct ggc_pch_data *d) | |
2352 | { | |
08cee789 DJ |
2353 | enum gt_types_enum i; |
2354 | size_t alloc_size, total_size; | |
2355 | ||
2356 | total_size = 0; | |
2357 | for (i = 0; i < NUM_PCH_BUCKETS; i++) | |
2358 | { | |
2359 | d->d.type_totals[i] = ROUND_UP (d->d.type_totals[i], GGC_PAGE_SIZE); | |
2360 | total_size += d->d.type_totals[i]; | |
2361 | } | |
2362 | d->d.total = total_size; | |
2363 | ||
2364 | /* Include the size of the allocation bitmap. */ | |
2365 | alloc_size = CEIL (d->d.total, BYTES_PER_ALLOC_BIT * 8); | |
2366 | alloc_size = ROUND_UP (alloc_size, MAX_ALIGNMENT); | |
2367 | d->alloc_size = alloc_size; | |
2368 | ||
2369 | return d->d.total + alloc_size; | |
b6f61163 DB |
2370 | } |
2371 | ||
2372 | /* Set the base address for the objects in the PCH file. */ | |
2373 | ||
2374 | void | |
08cee789 | 2375 | ggc_pch_this_base (struct ggc_pch_data *d, void *base_) |
b6f61163 | 2376 | { |
08cee789 DJ |
2377 | int i; |
2378 | size_t base = (size_t) base_; | |
2379 | ||
2380 | d->base = d->orig_base = base; | |
2381 | for (i = 0; i < NUM_PCH_BUCKETS; i++) | |
2382 | { | |
2383 | d->type_bases[i] = base; | |
2384 | base += d->d.type_totals[i]; | |
2385 | } | |
2386 | ||
2387 | if (d->alloc_bits == NULL) | |
bf8e9c49 | 2388 | d->alloc_bits = XCNEWVAR (alloc_type, d->alloc_size); |
b6f61163 DB |
2389 | } |
2390 | ||
2391 | /* Allocate a place for object X of size SIZE in the PCH file. */ | |
2392 | ||
2393 | char * | |
2394 | ggc_pch_alloc_object (struct ggc_pch_data *d, void *x, | |
08cee789 DJ |
2395 | size_t size, bool is_string, |
2396 | enum gt_types_enum type) | |
b6f61163 | 2397 | { |
08cee789 | 2398 | size_t alloc_word, alloc_bit; |
b6f61163 | 2399 | char *result; |
08cee789 DJ |
2400 | int bucket = pch_bucket (x, type, is_string); |
2401 | ||
2402 | /* Record the start of the object in the allocation bitmap. We | |
2403 | can't assert that the allocation bit is previously clear, because | |
2404 | strings may violate the invariant that they are at least | |
2405 | BYTES_PER_ALLOC_BIT long. This is harmless - ggc_get_size | |
2406 | should not be called for strings. */ | |
2407 | alloc_word = ((d->type_bases[bucket] - d->orig_base) | |
2408 | / (8 * sizeof (alloc_type) * BYTES_PER_ALLOC_BIT)); | |
2409 | alloc_bit = ((d->type_bases[bucket] - d->orig_base) | |
2410 | / BYTES_PER_ALLOC_BIT) % (8 * sizeof (alloc_type)); | |
2411 | d->alloc_bits[alloc_word] |= 1L << alloc_bit; | |
2412 | ||
2413 | /* Place the object at the current pointer for this bucket. */ | |
2414 | result = (char *) d->type_bases[bucket]; | |
2415 | d->type_bases[bucket] += size; | |
2416 | return result; | |
b6f61163 DB |
2417 | } |
2418 | ||
2419 | /* Prepare to write out the PCH data to file F. */ | |
2420 | ||
2421 | void | |
08cee789 DJ |
2422 | ggc_pch_prepare_write (struct ggc_pch_data *d, |
2423 | FILE *f) | |
b6f61163 | 2424 | { |
08cee789 DJ |
2425 | /* We seek around a lot while writing. Record where the end |
2426 | of the padding in the PCH file is, so that we can | |
2427 | locate each object's offset. */ | |
2428 | d->start_offset = ftell (f); | |
b6f61163 DB |
2429 | } |
2430 | ||
2431 | /* Write out object X of SIZE to file F. */ | |
2432 | ||
2433 | void | |
08cee789 DJ |
2434 | ggc_pch_write_object (struct ggc_pch_data *d, |
2435 | FILE *f, void *x, void *newx, | |
2436 | size_t size, bool is_string ATTRIBUTE_UNUSED) | |
b6f61163 | 2437 | { |
08cee789 DJ |
2438 | if (fseek (f, (size_t) newx - d->orig_base + d->start_offset, SEEK_SET) != 0) |
2439 | fatal_error ("can't seek PCH file: %m"); | |
2440 | ||
2441 | if (fwrite (x, size, 1, f) != 1) | |
2442 | fatal_error ("can't write PCH file: %m"); | |
b6f61163 DB |
2443 | } |
2444 | ||
2445 | void | |
2446 | ggc_pch_finish (struct ggc_pch_data *d, FILE *f) | |
2447 | { | |
08cee789 DJ |
2448 | /* Write out the allocation bitmap. */ |
2449 | if (fseek (f, d->start_offset + d->d.total, SEEK_SET) != 0) | |
2450 | fatal_error ("can't seek PCH file: %m"); | |
2451 | ||
2452 | if (fwrite (d->alloc_bits, d->alloc_size, 1, f) != 1) | |
fa10beec | 2453 | fatal_error ("can't write PCH file: %m"); |
08cee789 DJ |
2454 | |
2455 | /* Done with the PCH, so write out our footer. */ | |
b6f61163 DB |
2456 | if (fwrite (&d->d, sizeof (d->d), 1, f) != 1) |
2457 | fatal_error ("can't write PCH file: %m"); | |
08cee789 DJ |
2458 | |
2459 | free (d->alloc_bits); | |
b6f61163 DB |
2460 | free (d); |
2461 | } | |
08cee789 DJ |
2462 | |
2463 | /* The PCH file from F has been mapped at ADDR. Read in any | |
2464 | additional data from the file and set up the GC state. */ | |
2465 | ||
b6f61163 DB |
2466 | void |
2467 | ggc_pch_read (FILE *f, void *addr) | |
2468 | { | |
2469 | struct ggc_pch_ondisk d; | |
08cee789 DJ |
2470 | size_t alloc_size; |
2471 | struct alloc_zone *zone; | |
2472 | struct page_entry *pch_page; | |
2473 | char *p; | |
2474 | ||
b6f61163 DB |
2475 | if (fread (&d, sizeof (d), 1, f) != 1) |
2476 | fatal_error ("can't read PCH file: %m"); | |
08cee789 DJ |
2477 | |
2478 | alloc_size = CEIL (d.total, BYTES_PER_ALLOC_BIT * 8); | |
2479 | alloc_size = ROUND_UP (alloc_size, MAX_ALIGNMENT); | |
2480 | ||
2481 | pch_zone.bytes = d.total; | |
2482 | pch_zone.alloc_bits = (alloc_type *) ((char *) addr + pch_zone.bytes); | |
2483 | pch_zone.page = (char *) addr; | |
2484 | pch_zone.end = (char *) pch_zone.alloc_bits; | |
2485 | ||
2486 | /* We've just read in a PCH file. So, every object that used to be | |
2487 | allocated is now free. */ | |
2488 | for (zone = G.zones; zone; zone = zone->next_zone) | |
2489 | { | |
2490 | struct small_page_entry *page, *next_page; | |
2491 | struct large_page_entry *large_page, *next_large_page; | |
2492 | ||
2493 | zone->allocated = 0; | |
2494 | ||
2495 | /* Clear the zone's free chunk list. */ | |
2496 | memset (zone->free_chunks, 0, sizeof (zone->free_chunks)); | |
2497 | zone->high_free_bin = 0; | |
2498 | zone->cached_free = NULL; | |
2499 | zone->cached_free_size = 0; | |
2500 | ||
2501 | /* Move all the small pages onto the free list. */ | |
2502 | for (page = zone->pages; page != NULL; page = next_page) | |
2503 | { | |
2504 | next_page = page->next; | |
2505 | memset (page->alloc_bits, 0, | |
2506 | G.small_page_overhead - PAGE_OVERHEAD); | |
2507 | free_small_page (page); | |
2508 | } | |
2509 | ||
2510 | /* Discard all the large pages. */ | |
2511 | for (large_page = zone->large_pages; large_page != NULL; | |
2512 | large_page = next_large_page) | |
2513 | { | |
2514 | next_large_page = large_page->next; | |
2515 | free_large_page (large_page); | |
2516 | } | |
2517 | ||
2518 | zone->pages = NULL; | |
2519 | zone->large_pages = NULL; | |
2520 | } | |
2521 | ||
2522 | /* Allocate the dummy page entry for the PCH, and set all pages | |
2523 | mapped into the PCH to reference it. */ | |
bf8e9c49 | 2524 | pch_page = XCNEW (struct page_entry); |
08cee789 DJ |
2525 | pch_page->page = pch_zone.page; |
2526 | pch_page->pch_p = true; | |
2527 | ||
2528 | for (p = pch_zone.page; p < pch_zone.end; p += GGC_PAGE_SIZE) | |
2529 | set_page_table_entry (p, pch_page); | |
b6f61163 | 2530 | } |