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21341cfd | 1 | /* "Bag-of-pages" garbage collector for the GNU compiler. |
d1e082c2 | 2 | Copyright (C) 1999-2013 Free Software Foundation, Inc. |
21341cfd | 3 | |
1322177d | 4 | This file is part of GCC. |
21341cfd | 5 | |
1322177d LB |
6 | GCC is free software; you can redistribute it and/or modify it under |
7 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 8 | Software Foundation; either version 3, or (at your option) any later |
1322177d | 9 | version. |
21341cfd | 10 | |
1322177d LB |
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
21341cfd | 15 | |
b9bfacf0 | 16 | You should have received a copy of the GNU General Public License |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
21341cfd | 19 | |
21341cfd | 20 | #include "config.h" |
21341cfd | 21 | #include "system.h" |
4977bab6 ZW |
22 | #include "coretypes.h" |
23 | #include "tm.h" | |
21341cfd | 24 | #include "tree.h" |
e5ecd4ea | 25 | #include "rtl.h" |
1b42a6a9 | 26 | #include "tm_p.h" |
718f9c0f | 27 | #include "diagnostic-core.h" |
21341cfd | 28 | #include "flags.h" |
e5ecd4ea | 29 | #include "ggc.h" |
a9429e29 | 30 | #include "ggc-internal.h" |
2a9a326b | 31 | #include "timevar.h" |
3788cc17 | 32 | #include "params.h" |
442b4905 | 33 | #include "cgraph.h" |
b78cd885 | 34 | #include "cfgloop.h" |
ae2392a9 | 35 | #include "plugin.h" |
e5ecd4ea | 36 | |
825b6926 ZW |
37 | /* Prefer MAP_ANON(YMOUS) to /dev/zero, since we don't need to keep a |
38 | file open. Prefer either to valloc. */ | |
39 | #ifdef HAVE_MMAP_ANON | |
40 | # undef HAVE_MMAP_DEV_ZERO | |
825b6926 | 41 | # define USING_MMAP |
005537df | 42 | #endif |
21341cfd | 43 | |
825b6926 | 44 | #ifdef HAVE_MMAP_DEV_ZERO |
825b6926 | 45 | # define USING_MMAP |
8342b467 RH |
46 | #endif |
47 | ||
130fadbb RH |
48 | #ifndef USING_MMAP |
49 | #define USING_MALLOC_PAGE_GROUPS | |
5b918807 | 50 | #endif |
21341cfd | 51 | |
87fb500b RO |
52 | #if defined(HAVE_MADVISE) && HAVE_DECL_MADVISE && defined(MADV_DONTNEED) \ |
53 | && defined(USING_MMAP) | |
711a3d82 AK |
54 | # define USING_MADVISE |
55 | #endif | |
56 | ||
0fa2e4df | 57 | /* Strategy: |
21341cfd AS |
58 | |
59 | This garbage-collecting allocator allocates objects on one of a set | |
60 | of pages. Each page can allocate objects of a single size only; | |
61 | available sizes are powers of two starting at four bytes. The size | |
62 | of an allocation request is rounded up to the next power of two | |
63 | (`order'), and satisfied from the appropriate page. | |
64 | ||
65 | Each page is recorded in a page-entry, which also maintains an | |
66 | in-use bitmap of object positions on the page. This allows the | |
67 | allocation state of a particular object to be flipped without | |
68 | touching the page itself. | |
69 | ||
70 | Each page-entry also has a context depth, which is used to track | |
71 | pushing and popping of allocation contexts. Only objects allocated | |
589005ff | 72 | in the current (highest-numbered) context may be collected. |
21341cfd AS |
73 | |
74 | Page entries are arranged in an array of singly-linked lists. The | |
75 | array is indexed by the allocation size, in bits, of the pages on | |
76 | it; i.e. all pages on a list allocate objects of the same size. | |
77 | Pages are ordered on the list such that all non-full pages precede | |
78 | all full pages, with non-full pages arranged in order of decreasing | |
79 | context depth. | |
80 | ||
81 | Empty pages (of all orders) are kept on a single page cache list, | |
82 | and are considered first when new pages are required; they are | |
83 | deallocated at the start of the next collection if they haven't | |
84 | been recycled by then. */ | |
85 | ||
21341cfd AS |
86 | /* Define GGC_DEBUG_LEVEL to print debugging information. |
87 | 0: No debugging output. | |
88 | 1: GC statistics only. | |
89 | 2: Page-entry allocations/deallocations as well. | |
90 | 3: Object allocations as well. | |
6d2f8887 | 91 | 4: Object marks as well. */ |
21341cfd AS |
92 | #define GGC_DEBUG_LEVEL (0) |
93 | \f | |
94 | #ifndef HOST_BITS_PER_PTR | |
95 | #define HOST_BITS_PER_PTR HOST_BITS_PER_LONG | |
96 | #endif | |
97 | ||
21341cfd AS |
98 | \f |
99 | /* A two-level tree is used to look up the page-entry for a given | |
100 | pointer. Two chunks of the pointer's bits are extracted to index | |
101 | the first and second levels of the tree, as follows: | |
102 | ||
103 | HOST_PAGE_SIZE_BITS | |
104 | 32 | | | |
105 | msb +----------------+----+------+------+ lsb | |
106 | | | | | |
107 | PAGE_L1_BITS | | |
108 | | | | |
109 | PAGE_L2_BITS | |
110 | ||
111 | The bottommost HOST_PAGE_SIZE_BITS are ignored, since page-entry | |
112 | pages are aligned on system page boundaries. The next most | |
113 | significant PAGE_L2_BITS and PAGE_L1_BITS are the second and first | |
589005ff | 114 | index values in the lookup table, respectively. |
21341cfd | 115 | |
005537df RH |
116 | For 32-bit architectures and the settings below, there are no |
117 | leftover bits. For architectures with wider pointers, the lookup | |
118 | tree points to a list of pages, which must be scanned to find the | |
119 | correct one. */ | |
21341cfd AS |
120 | |
121 | #define PAGE_L1_BITS (8) | |
122 | #define PAGE_L2_BITS (32 - PAGE_L1_BITS - G.lg_pagesize) | |
2a6e6fea TG |
123 | #define PAGE_L1_SIZE ((uintptr_t) 1 << PAGE_L1_BITS) |
124 | #define PAGE_L2_SIZE ((uintptr_t) 1 << PAGE_L2_BITS) | |
21341cfd AS |
125 | |
126 | #define LOOKUP_L1(p) \ | |
2a6e6fea | 127 | (((uintptr_t) (p) >> (32 - PAGE_L1_BITS)) & ((1 << PAGE_L1_BITS) - 1)) |
21341cfd AS |
128 | |
129 | #define LOOKUP_L2(p) \ | |
2a6e6fea | 130 | (((uintptr_t) (p) >> G.lg_pagesize) & ((1 << PAGE_L2_BITS) - 1)) |
21341cfd | 131 | |
2be510b8 MM |
132 | /* The number of objects per allocation page, for objects on a page of |
133 | the indicated ORDER. */ | |
134 | #define OBJECTS_PER_PAGE(ORDER) objects_per_page_table[ORDER] | |
135 | ||
17211ab5 GK |
136 | /* The number of objects in P. */ |
137 | #define OBJECTS_IN_PAGE(P) ((P)->bytes / OBJECT_SIZE ((P)->order)) | |
138 | ||
2be510b8 MM |
139 | /* The size of an object on a page of the indicated ORDER. */ |
140 | #define OBJECT_SIZE(ORDER) object_size_table[ORDER] | |
141 | ||
8537ed68 ZW |
142 | /* For speed, we avoid doing a general integer divide to locate the |
143 | offset in the allocation bitmap, by precalculating numbers M, S | |
144 | such that (O * M) >> S == O / Z (modulo 2^32), for any offset O | |
145 | within the page which is evenly divisible by the object size Z. */ | |
146 | #define DIV_MULT(ORDER) inverse_table[ORDER].mult | |
147 | #define DIV_SHIFT(ORDER) inverse_table[ORDER].shift | |
148 | #define OFFSET_TO_BIT(OFFSET, ORDER) \ | |
149 | (((OFFSET) * DIV_MULT (ORDER)) >> DIV_SHIFT (ORDER)) | |
150 | ||
b78cd885 RG |
151 | /* We use this structure to determine the alignment required for |
152 | allocations. For power-of-two sized allocations, that's not a | |
153 | problem, but it does matter for odd-sized allocations. | |
154 | We do not care about alignment for floating-point types. */ | |
155 | ||
156 | struct max_alignment { | |
157 | char c; | |
158 | union { | |
159 | HOST_WIDEST_INT i; | |
160 | void *p; | |
161 | } u; | |
162 | }; | |
163 | ||
164 | /* The biggest alignment required. */ | |
165 | ||
166 | #define MAX_ALIGNMENT (offsetof (struct max_alignment, u)) | |
167 | ||
168 | ||
2be510b8 MM |
169 | /* The number of extra orders, not corresponding to power-of-two sized |
170 | objects. */ | |
171 | ||
ca7558fc | 172 | #define NUM_EXTRA_ORDERS ARRAY_SIZE (extra_order_size_table) |
2be510b8 | 173 | |
d1f1cc6a | 174 | #define RTL_SIZE(NSLOTS) \ |
e1de1560 | 175 | (RTX_HDR_SIZE + (NSLOTS) * sizeof (rtunion)) |
d1f1cc6a | 176 | |
5e26df64 SB |
177 | #define TREE_EXP_SIZE(OPS) \ |
178 | (sizeof (struct tree_exp) + ((OPS) - 1) * sizeof (tree)) | |
179 | ||
2be510b8 MM |
180 | /* The Ith entry is the maximum size of an object to be stored in the |
181 | Ith extra order. Adding a new entry to this array is the *only* | |
182 | thing you need to do to add a new special allocation size. */ | |
183 | ||
184 | static const size_t extra_order_size_table[] = { | |
b78cd885 RG |
185 | /* Extra orders for small non-power-of-two multiples of MAX_ALIGNMENT. |
186 | There are a lot of structures with these sizes and explicitly | |
187 | listing them risks orders being dropped because they changed size. */ | |
188 | MAX_ALIGNMENT * 3, | |
189 | MAX_ALIGNMENT * 5, | |
190 | MAX_ALIGNMENT * 6, | |
191 | MAX_ALIGNMENT * 7, | |
192 | MAX_ALIGNMENT * 9, | |
193 | MAX_ALIGNMENT * 10, | |
194 | MAX_ALIGNMENT * 11, | |
195 | MAX_ALIGNMENT * 12, | |
196 | MAX_ALIGNMENT * 13, | |
197 | MAX_ALIGNMENT * 14, | |
198 | MAX_ALIGNMENT * 15, | |
820cc88f DB |
199 | sizeof (struct tree_decl_non_common), |
200 | sizeof (struct tree_field_decl), | |
201 | sizeof (struct tree_parm_decl), | |
202 | sizeof (struct tree_var_decl), | |
51545682 | 203 | sizeof (struct tree_type_non_common), |
f5938dcd RG |
204 | sizeof (struct function), |
205 | sizeof (struct basic_block_def), | |
b78cd885 RG |
206 | sizeof (struct cgraph_node), |
207 | sizeof (struct loop), | |
2be510b8 MM |
208 | }; |
209 | ||
210 | /* The total number of orders. */ | |
211 | ||
212 | #define NUM_ORDERS (HOST_BITS_PER_PTR + NUM_EXTRA_ORDERS) | |
213 | ||
17211ab5 GK |
214 | /* Compute the smallest nonnegative number which when added to X gives |
215 | a multiple of F. */ | |
216 | ||
217 | #define ROUND_UP_VALUE(x, f) ((f) - 1 - ((f) - 1 + (x)) % (f)) | |
218 | ||
219 | /* Compute the smallest multiple of F that is >= X. */ | |
220 | ||
221 | #define ROUND_UP(x, f) (CEIL (x, f) * (f)) | |
222 | ||
3bc50163 AK |
223 | /* Round X to next multiple of the page size */ |
224 | ||
225 | #define PAGE_ALIGN(x) (((x) + G.pagesize - 1) & ~(G.pagesize - 1)) | |
226 | ||
2be510b8 MM |
227 | /* The Ith entry is the number of objects on a page or order I. */ |
228 | ||
229 | static unsigned objects_per_page_table[NUM_ORDERS]; | |
230 | ||
231 | /* The Ith entry is the size of an object on a page of order I. */ | |
232 | ||
233 | static size_t object_size_table[NUM_ORDERS]; | |
21341cfd | 234 | |
8537ed68 ZW |
235 | /* The Ith entry is a pair of numbers (mult, shift) such that |
236 | ((k * mult) >> shift) mod 2^32 == (k / OBJECT_SIZE(I)) mod 2^32, | |
237 | for all k evenly divisible by OBJECT_SIZE(I). */ | |
238 | ||
239 | static struct | |
240 | { | |
75d75435 | 241 | size_t mult; |
8537ed68 ZW |
242 | unsigned int shift; |
243 | } | |
244 | inverse_table[NUM_ORDERS]; | |
245 | ||
21341cfd AS |
246 | /* A page_entry records the status of an allocation page. This |
247 | structure is dynamically sized to fit the bitmap in_use_p. */ | |
589005ff | 248 | typedef struct page_entry |
21341cfd AS |
249 | { |
250 | /* The next page-entry with objects of the same size, or NULL if | |
251 | this is the last page-entry. */ | |
252 | struct page_entry *next; | |
253 | ||
9bf793f9 JL |
254 | /* The previous page-entry with objects of the same size, or NULL if |
255 | this is the first page-entry. The PREV pointer exists solely to | |
71cc389b | 256 | keep the cost of ggc_free manageable. */ |
9bf793f9 JL |
257 | struct page_entry *prev; |
258 | ||
21341cfd AS |
259 | /* The number of bytes allocated. (This will always be a multiple |
260 | of the host system page size.) */ | |
261 | size_t bytes; | |
262 | ||
263 | /* The address at which the memory is allocated. */ | |
264 | char *page; | |
265 | ||
130fadbb RH |
266 | #ifdef USING_MALLOC_PAGE_GROUPS |
267 | /* Back pointer to the page group this page came from. */ | |
268 | struct page_group *group; | |
269 | #endif | |
270 | ||
c4775f82 MS |
271 | /* This is the index in the by_depth varray where this page table |
272 | can be found. */ | |
273 | unsigned long index_by_depth; | |
21341cfd AS |
274 | |
275 | /* Context depth of this page. */ | |
ae373eda | 276 | unsigned short context_depth; |
21341cfd AS |
277 | |
278 | /* The number of free objects remaining on this page. */ | |
279 | unsigned short num_free_objects; | |
280 | ||
281 | /* A likely candidate for the bit position of a free object for the | |
282 | next allocation from this page. */ | |
283 | unsigned short next_bit_hint; | |
284 | ||
ae373eda MM |
285 | /* The lg of size of objects allocated from this page. */ |
286 | unsigned char order; | |
287 | ||
711a3d82 AK |
288 | /* Discarded page? */ |
289 | bool discarded; | |
290 | ||
21341cfd AS |
291 | /* A bit vector indicating whether or not objects are in use. The |
292 | Nth bit is one if the Nth object on this page is allocated. This | |
293 | array is dynamically sized. */ | |
294 | unsigned long in_use_p[1]; | |
295 | } page_entry; | |
296 | ||
130fadbb RH |
297 | #ifdef USING_MALLOC_PAGE_GROUPS |
298 | /* A page_group describes a large allocation from malloc, from which | |
299 | we parcel out aligned pages. */ | |
300 | typedef struct page_group | |
301 | { | |
302 | /* A linked list of all extant page groups. */ | |
303 | struct page_group *next; | |
304 | ||
305 | /* The address we received from malloc. */ | |
306 | char *allocation; | |
307 | ||
308 | /* The size of the block. */ | |
309 | size_t alloc_size; | |
310 | ||
311 | /* A bitmask of pages in use. */ | |
312 | unsigned int in_use; | |
313 | } page_group; | |
314 | #endif | |
21341cfd AS |
315 | |
316 | #if HOST_BITS_PER_PTR <= 32 | |
317 | ||
318 | /* On 32-bit hosts, we use a two level page table, as pictured above. */ | |
319 | typedef page_entry **page_table[PAGE_L1_SIZE]; | |
320 | ||
321 | #else | |
322 | ||
005537df RH |
323 | /* On 64-bit hosts, we use the same two level page tables plus a linked |
324 | list that disambiguates the top 32-bits. There will almost always be | |
21341cfd AS |
325 | exactly one entry in the list. */ |
326 | typedef struct page_table_chain | |
327 | { | |
328 | struct page_table_chain *next; | |
329 | size_t high_bits; | |
330 | page_entry **table[PAGE_L1_SIZE]; | |
331 | } *page_table; | |
332 | ||
333 | #endif | |
334 | ||
9957322d DK |
335 | #ifdef ENABLE_GC_ALWAYS_COLLECT |
336 | /* List of free objects to be verified as actually free on the | |
337 | next collection. */ | |
338 | struct free_object | |
339 | { | |
340 | void *object; | |
341 | struct free_object *next; | |
342 | }; | |
343 | #endif | |
344 | ||
21341cfd AS |
345 | /* The rest of the global variables. */ |
346 | static struct globals | |
347 | { | |
348 | /* The Nth element in this array is a page with objects of size 2^N. | |
349 | If there are any pages with free objects, they will be at the | |
350 | head of the list. NULL if there are no page-entries for this | |
351 | object size. */ | |
2be510b8 | 352 | page_entry *pages[NUM_ORDERS]; |
21341cfd AS |
353 | |
354 | /* The Nth element in this array is the last page with objects of | |
355 | size 2^N. NULL if there are no page-entries for this object | |
356 | size. */ | |
2be510b8 | 357 | page_entry *page_tails[NUM_ORDERS]; |
21341cfd AS |
358 | |
359 | /* Lookup table for associating allocation pages with object addresses. */ | |
360 | page_table lookup; | |
361 | ||
362 | /* The system's page size. */ | |
363 | size_t pagesize; | |
364 | size_t lg_pagesize; | |
365 | ||
366 | /* Bytes currently allocated. */ | |
367 | size_t allocated; | |
368 | ||
369 | /* Bytes currently allocated at the end of the last collection. */ | |
370 | size_t allocated_last_gc; | |
371 | ||
3277221c MM |
372 | /* Total amount of memory mapped. */ |
373 | size_t bytes_mapped; | |
374 | ||
52895e1a RH |
375 | /* Bit N set if any allocations have been done at context depth N. */ |
376 | unsigned long context_depth_allocations; | |
377 | ||
378 | /* Bit N set if any collections have been done at context depth N. */ | |
379 | unsigned long context_depth_collections; | |
380 | ||
21341cfd | 381 | /* The current depth in the context stack. */ |
d416576b | 382 | unsigned short context_depth; |
21341cfd AS |
383 | |
384 | /* A file descriptor open to /dev/zero for reading. */ | |
825b6926 | 385 | #if defined (HAVE_MMAP_DEV_ZERO) |
21341cfd AS |
386 | int dev_zero_fd; |
387 | #endif | |
388 | ||
389 | /* A cache of free system pages. */ | |
390 | page_entry *free_pages; | |
391 | ||
130fadbb RH |
392 | #ifdef USING_MALLOC_PAGE_GROUPS |
393 | page_group *page_groups; | |
394 | #endif | |
395 | ||
21341cfd AS |
396 | /* The file descriptor for debugging output. */ |
397 | FILE *debug_file; | |
c4775f82 MS |
398 | |
399 | /* Current number of elements in use in depth below. */ | |
400 | unsigned int depth_in_use; | |
401 | ||
402 | /* Maximum number of elements that can be used before resizing. */ | |
403 | unsigned int depth_max; | |
404 | ||
fa10beec | 405 | /* Each element of this array is an index in by_depth where the given |
c4775f82 MS |
406 | depth starts. This structure is indexed by that given depth we |
407 | are interested in. */ | |
408 | unsigned int *depth; | |
409 | ||
410 | /* Current number of elements in use in by_depth below. */ | |
411 | unsigned int by_depth_in_use; | |
412 | ||
413 | /* Maximum number of elements that can be used before resizing. */ | |
414 | unsigned int by_depth_max; | |
415 | ||
416 | /* Each element of this array is a pointer to a page_entry, all | |
417 | page_entries can be found in here by increasing depth. | |
418 | index_by_depth in the page_entry is the index into this data | |
419 | structure where that page_entry can be found. This is used to | |
420 | speed up finding all page_entries at a particular depth. */ | |
421 | page_entry **by_depth; | |
422 | ||
423 | /* Each element is a pointer to the saved in_use_p bits, if any, | |
424 | zero otherwise. We allocate them all together, to enable a | |
425 | better runtime data access pattern. */ | |
426 | unsigned long **save_in_use; | |
685fe032 RH |
427 | |
428 | #ifdef ENABLE_GC_ALWAYS_COLLECT | |
429 | /* List of free objects to be verified as actually free on the | |
430 | next collection. */ | |
9957322d | 431 | struct free_object *free_object_list; |
685fe032 RH |
432 | #endif |
433 | ||
adc4adcd GP |
434 | struct |
435 | { | |
a9429e29 | 436 | /* Total GC-allocated memory. */ |
adc4adcd | 437 | unsigned long long total_allocated; |
a9429e29 | 438 | /* Total overhead for GC-allocated memory. */ |
adc4adcd GP |
439 | unsigned long long total_overhead; |
440 | ||
441 | /* Total allocations and overhead for sizes less than 32, 64 and 128. | |
442 | These sizes are interesting because they are typical cache line | |
938d968e | 443 | sizes. */ |
b8698a0f | 444 | |
adc4adcd GP |
445 | unsigned long long total_allocated_under32; |
446 | unsigned long long total_overhead_under32; | |
b8698a0f | 447 | |
adc4adcd GP |
448 | unsigned long long total_allocated_under64; |
449 | unsigned long long total_overhead_under64; | |
b8698a0f | 450 | |
adc4adcd GP |
451 | unsigned long long total_allocated_under128; |
452 | unsigned long long total_overhead_under128; | |
b8698a0f | 453 | |
439a7e54 DN |
454 | /* The allocations for each of the allocation orders. */ |
455 | unsigned long long total_allocated_per_order[NUM_ORDERS]; | |
456 | ||
938d968e | 457 | /* The overhead for each of the allocation orders. */ |
adc4adcd GP |
458 | unsigned long long total_overhead_per_order[NUM_ORDERS]; |
459 | } stats; | |
21341cfd AS |
460 | } G; |
461 | ||
21341cfd AS |
462 | /* The size in bytes required to maintain a bitmap for the objects |
463 | on a page-entry. */ | |
464 | #define BITMAP_SIZE(Num_objects) \ | |
c3284718 | 465 | (CEIL ((Num_objects), HOST_BITS_PER_LONG) * sizeof (long)) |
21341cfd | 466 | |
130fadbb RH |
467 | /* Allocate pages in chunks of this size, to throttle calls to memory |
468 | allocation routines. The first page is used, the rest go onto the | |
469 | free list. This cannot be larger than HOST_BITS_PER_INT for the | |
772299b3 | 470 | in_use bitmask for page_group. Hosts that need a different value |
471854f8 | 471 | can override this by defining GGC_QUIRE_SIZE explicitly. */ |
772299b3 MA |
472 | #ifndef GGC_QUIRE_SIZE |
473 | # ifdef USING_MMAP | |
6c995fa5 | 474 | # define GGC_QUIRE_SIZE 512 /* 2MB for 4K pages */ |
772299b3 MA |
475 | # else |
476 | # define GGC_QUIRE_SIZE 16 | |
477 | # endif | |
478 | #endif | |
c4775f82 MS |
479 | |
480 | /* Initial guess as to how many page table entries we might need. */ | |
481 | #define INITIAL_PTE_COUNT 128 | |
21341cfd | 482 | \f |
20c1dc5e AJ |
483 | static int ggc_allocated_p (const void *); |
484 | static page_entry *lookup_page_table_entry (const void *); | |
485 | static void set_page_table_entry (void *, page_entry *); | |
130fadbb | 486 | #ifdef USING_MMAP |
25f0ea81 | 487 | static char *alloc_anon (char *, size_t, bool check); |
130fadbb RH |
488 | #endif |
489 | #ifdef USING_MALLOC_PAGE_GROUPS | |
20c1dc5e AJ |
490 | static size_t page_group_index (char *, char *); |
491 | static void set_page_group_in_use (page_group *, char *); | |
492 | static void clear_page_group_in_use (page_group *, char *); | |
130fadbb | 493 | #endif |
20c1dc5e AJ |
494 | static struct page_entry * alloc_page (unsigned); |
495 | static void free_page (struct page_entry *); | |
496 | static void release_pages (void); | |
497 | static void clear_marks (void); | |
498 | static void sweep_pages (void); | |
499 | static void ggc_recalculate_in_use_p (page_entry *); | |
500 | static void compute_inverse (unsigned); | |
501 | static inline void adjust_depth (void); | |
502 | static void move_ptes_to_front (int, int); | |
21341cfd | 503 | |
20c1dc5e AJ |
504 | void debug_print_page_list (int); |
505 | static void push_depth (unsigned int); | |
506 | static void push_by_depth (page_entry *, unsigned long *); | |
b6f61163 | 507 | |
c4775f82 MS |
508 | /* Push an entry onto G.depth. */ |
509 | ||
510 | inline static void | |
20c1dc5e | 511 | push_depth (unsigned int i) |
c4775f82 MS |
512 | { |
513 | if (G.depth_in_use >= G.depth_max) | |
514 | { | |
515 | G.depth_max *= 2; | |
d3bfe4de | 516 | G.depth = XRESIZEVEC (unsigned int, G.depth, G.depth_max); |
c4775f82 MS |
517 | } |
518 | G.depth[G.depth_in_use++] = i; | |
519 | } | |
520 | ||
521 | /* Push an entry onto G.by_depth and G.save_in_use. */ | |
522 | ||
523 | inline static void | |
20c1dc5e | 524 | push_by_depth (page_entry *p, unsigned long *s) |
c4775f82 MS |
525 | { |
526 | if (G.by_depth_in_use >= G.by_depth_max) | |
527 | { | |
528 | G.by_depth_max *= 2; | |
d3bfe4de KG |
529 | G.by_depth = XRESIZEVEC (page_entry *, G.by_depth, G.by_depth_max); |
530 | G.save_in_use = XRESIZEVEC (unsigned long *, G.save_in_use, | |
531 | G.by_depth_max); | |
c4775f82 MS |
532 | } |
533 | G.by_depth[G.by_depth_in_use] = p; | |
534 | G.save_in_use[G.by_depth_in_use++] = s; | |
535 | } | |
536 | ||
537 | #if (GCC_VERSION < 3001) | |
538 | #define prefetch(X) ((void) X) | |
539 | #else | |
540 | #define prefetch(X) __builtin_prefetch (X) | |
541 | #endif | |
542 | ||
543 | #define save_in_use_p_i(__i) \ | |
544 | (G.save_in_use[__i]) | |
545 | #define save_in_use_p(__p) \ | |
546 | (save_in_use_p_i (__p->index_by_depth)) | |
547 | ||
cc2902df | 548 | /* Returns nonzero if P was allocated in GC'able memory. */ |
21341cfd | 549 | |
005537df | 550 | static inline int |
20c1dc5e | 551 | ggc_allocated_p (const void *p) |
21341cfd AS |
552 | { |
553 | page_entry ***base; | |
005537df | 554 | size_t L1, L2; |
21341cfd AS |
555 | |
556 | #if HOST_BITS_PER_PTR <= 32 | |
557 | base = &G.lookup[0]; | |
558 | #else | |
559 | page_table table = G.lookup; | |
2a6e6fea | 560 | uintptr_t high_bits = (uintptr_t) p & ~ (uintptr_t) 0xffffffff; |
005537df RH |
561 | while (1) |
562 | { | |
563 | if (table == NULL) | |
564 | return 0; | |
565 | if (table->high_bits == high_bits) | |
566 | break; | |
567 | table = table->next; | |
568 | } | |
21341cfd AS |
569 | base = &table->table[0]; |
570 | #endif | |
571 | ||
eaec9b3d | 572 | /* Extract the level 1 and 2 indices. */ |
74c937ca MM |
573 | L1 = LOOKUP_L1 (p); |
574 | L2 = LOOKUP_L2 (p); | |
575 | ||
576 | return base[L1] && base[L1][L2]; | |
577 | } | |
578 | ||
589005ff | 579 | /* Traverse the page table and find the entry for a page. |
74c937ca MM |
580 | Die (probably) if the object wasn't allocated via GC. */ |
581 | ||
582 | static inline page_entry * | |
20c1dc5e | 583 | lookup_page_table_entry (const void *p) |
74c937ca MM |
584 | { |
585 | page_entry ***base; | |
586 | size_t L1, L2; | |
587 | ||
005537df RH |
588 | #if HOST_BITS_PER_PTR <= 32 |
589 | base = &G.lookup[0]; | |
590 | #else | |
591 | page_table table = G.lookup; | |
2a6e6fea | 592 | uintptr_t high_bits = (uintptr_t) p & ~ (uintptr_t) 0xffffffff; |
005537df RH |
593 | while (table->high_bits != high_bits) |
594 | table = table->next; | |
595 | base = &table->table[0]; | |
596 | #endif | |
74c937ca | 597 | |
eaec9b3d | 598 | /* Extract the level 1 and 2 indices. */ |
21341cfd AS |
599 | L1 = LOOKUP_L1 (p); |
600 | L2 = LOOKUP_L2 (p); | |
601 | ||
602 | return base[L1][L2]; | |
603 | } | |
604 | ||
21341cfd | 605 | /* Set the page table entry for a page. */ |
cb2ec151 | 606 | |
21341cfd | 607 | static void |
20c1dc5e | 608 | set_page_table_entry (void *p, page_entry *entry) |
21341cfd AS |
609 | { |
610 | page_entry ***base; | |
611 | size_t L1, L2; | |
612 | ||
613 | #if HOST_BITS_PER_PTR <= 32 | |
614 | base = &G.lookup[0]; | |
615 | #else | |
616 | page_table table; | |
2a6e6fea | 617 | uintptr_t high_bits = (uintptr_t) p & ~ (uintptr_t) 0xffffffff; |
21341cfd AS |
618 | for (table = G.lookup; table; table = table->next) |
619 | if (table->high_bits == high_bits) | |
620 | goto found; | |
621 | ||
622 | /* Not found -- allocate a new table. */ | |
4dc6c528 | 623 | table = XCNEW (struct page_table_chain); |
21341cfd AS |
624 | table->next = G.lookup; |
625 | table->high_bits = high_bits; | |
626 | G.lookup = table; | |
627 | found: | |
628 | base = &table->table[0]; | |
629 | #endif | |
630 | ||
eaec9b3d | 631 | /* Extract the level 1 and 2 indices. */ |
21341cfd AS |
632 | L1 = LOOKUP_L1 (p); |
633 | L2 = LOOKUP_L2 (p); | |
634 | ||
635 | if (base[L1] == NULL) | |
5ed6ace5 | 636 | base[L1] = XCNEWVEC (page_entry *, PAGE_L2_SIZE); |
21341cfd AS |
637 | |
638 | base[L1][L2] = entry; | |
639 | } | |
640 | ||
21341cfd | 641 | /* Prints the page-entry for object size ORDER, for debugging. */ |
cb2ec151 | 642 | |
24e47c76 | 643 | DEBUG_FUNCTION void |
20c1dc5e | 644 | debug_print_page_list (int order) |
21341cfd AS |
645 | { |
646 | page_entry *p; | |
20c1dc5e AJ |
647 | printf ("Head=%p, Tail=%p:\n", (void *) G.pages[order], |
648 | (void *) G.page_tails[order]); | |
21341cfd AS |
649 | p = G.pages[order]; |
650 | while (p != NULL) | |
651 | { | |
20c1dc5e | 652 | printf ("%p(%1d|%3d) -> ", (void *) p, p->context_depth, |
683eb0e9 | 653 | p->num_free_objects); |
21341cfd AS |
654 | p = p->next; |
655 | } | |
656 | printf ("NULL\n"); | |
657 | fflush (stdout); | |
658 | } | |
659 | ||
130fadbb | 660 | #ifdef USING_MMAP |
21341cfd | 661 | /* Allocate SIZE bytes of anonymous memory, preferably near PREF, |
825b6926 ZW |
662 | (if non-null). The ifdef structure here is intended to cause a |
663 | compile error unless exactly one of the HAVE_* is defined. */ | |
cb2ec151 | 664 | |
21341cfd | 665 | static inline char * |
25f0ea81 | 666 | alloc_anon (char *pref ATTRIBUTE_UNUSED, size_t size, bool check) |
21341cfd | 667 | { |
825b6926 | 668 | #ifdef HAVE_MMAP_ANON |
d3bfe4de KG |
669 | char *page = (char *) mmap (pref, size, PROT_READ | PROT_WRITE, |
670 | MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); | |
825b6926 ZW |
671 | #endif |
672 | #ifdef HAVE_MMAP_DEV_ZERO | |
d3bfe4de KG |
673 | char *page = (char *) mmap (pref, size, PROT_READ | PROT_WRITE, |
674 | MAP_PRIVATE, G.dev_zero_fd, 0); | |
21341cfd | 675 | #endif |
825b6926 ZW |
676 | |
677 | if (page == (char *) MAP_FAILED) | |
005537df | 678 | { |
25f0ea81 AK |
679 | if (!check) |
680 | return NULL; | |
1f978f5f | 681 | perror ("virtual memory exhausted"); |
bd0f0717 | 682 | exit (FATAL_EXIT_CODE); |
005537df | 683 | } |
21341cfd | 684 | |
3277221c MM |
685 | /* Remember that we allocated this memory. */ |
686 | G.bytes_mapped += size; | |
687 | ||
9a0a7d5d | 688 | /* Pretend we don't have access to the allocated pages. We'll enable |
a9429e29 | 689 | access to smaller pieces of the area in ggc_internal_alloc. Discard the |
9a0a7d5d | 690 | handle to avoid handle leak. */ |
35dee980 | 691 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (page, size)); |
9a0a7d5d | 692 | |
21341cfd AS |
693 | return page; |
694 | } | |
130fadbb RH |
695 | #endif |
696 | #ifdef USING_MALLOC_PAGE_GROUPS | |
697 | /* Compute the index for this page into the page group. */ | |
698 | ||
699 | static inline size_t | |
20c1dc5e | 700 | page_group_index (char *allocation, char *page) |
130fadbb | 701 | { |
c4f2c499 | 702 | return (size_t) (page - allocation) >> G.lg_pagesize; |
130fadbb RH |
703 | } |
704 | ||
705 | /* Set and clear the in_use bit for this page in the page group. */ | |
706 | ||
707 | static inline void | |
20c1dc5e | 708 | set_page_group_in_use (page_group *group, char *page) |
130fadbb RH |
709 | { |
710 | group->in_use |= 1 << page_group_index (group->allocation, page); | |
711 | } | |
712 | ||
713 | static inline void | |
20c1dc5e | 714 | clear_page_group_in_use (page_group *group, char *page) |
130fadbb RH |
715 | { |
716 | group->in_use &= ~(1 << page_group_index (group->allocation, page)); | |
717 | } | |
718 | #endif | |
21341cfd AS |
719 | |
720 | /* Allocate a new page for allocating objects of size 2^ORDER, | |
721 | and return an entry for it. The entry is not added to the | |
722 | appropriate page_table list. */ | |
cb2ec151 | 723 | |
21341cfd | 724 | static inline struct page_entry * |
20c1dc5e | 725 | alloc_page (unsigned order) |
21341cfd AS |
726 | { |
727 | struct page_entry *entry, *p, **pp; | |
728 | char *page; | |
729 | size_t num_objects; | |
730 | size_t bitmap_size; | |
731 | size_t page_entry_size; | |
732 | size_t entry_size; | |
130fadbb RH |
733 | #ifdef USING_MALLOC_PAGE_GROUPS |
734 | page_group *group; | |
735 | #endif | |
21341cfd AS |
736 | |
737 | num_objects = OBJECTS_PER_PAGE (order); | |
738 | bitmap_size = BITMAP_SIZE (num_objects + 1); | |
739 | page_entry_size = sizeof (page_entry) - sizeof (long) + bitmap_size; | |
2be510b8 | 740 | entry_size = num_objects * OBJECT_SIZE (order); |
ca79429a RH |
741 | if (entry_size < G.pagesize) |
742 | entry_size = G.pagesize; | |
3bc50163 | 743 | entry_size = PAGE_ALIGN (entry_size); |
21341cfd AS |
744 | |
745 | entry = NULL; | |
746 | page = NULL; | |
747 | ||
748 | /* Check the list of free pages for one we can use. */ | |
bd0f0717 | 749 | for (pp = &G.free_pages, p = *pp; p; pp = &p->next, p = *pp) |
21341cfd AS |
750 | if (p->bytes == entry_size) |
751 | break; | |
752 | ||
753 | if (p != NULL) | |
754 | { | |
711a3d82 AK |
755 | if (p->discarded) |
756 | G.bytes_mapped += p->bytes; | |
757 | p->discarded = false; | |
758 | ||
dc297297 | 759 | /* Recycle the allocated memory from this page ... */ |
21341cfd AS |
760 | *pp = p->next; |
761 | page = p->page; | |
bd0f0717 | 762 | |
130fadbb RH |
763 | #ifdef USING_MALLOC_PAGE_GROUPS |
764 | group = p->group; | |
765 | #endif | |
bd0f0717 | 766 | |
21341cfd AS |
767 | /* ... and, if possible, the page entry itself. */ |
768 | if (p->order == order) | |
769 | { | |
770 | entry = p; | |
771 | memset (entry, 0, page_entry_size); | |
772 | } | |
773 | else | |
774 | free (p); | |
775 | } | |
825b6926 | 776 | #ifdef USING_MMAP |
054f5e69 | 777 | else if (entry_size == G.pagesize) |
21341cfd | 778 | { |
054f5e69 ZW |
779 | /* We want just one page. Allocate a bunch of them and put the |
780 | extras on the freelist. (Can only do this optimization with | |
781 | mmap for backing store.) */ | |
782 | struct page_entry *e, *f = G.free_pages; | |
25f0ea81 | 783 | int i, entries = GGC_QUIRE_SIZE; |
054f5e69 | 784 | |
25f0ea81 AK |
785 | page = alloc_anon (NULL, G.pagesize * GGC_QUIRE_SIZE, false); |
786 | if (page == NULL) | |
787 | { | |
c3284718 | 788 | page = alloc_anon (NULL, G.pagesize, true); |
25f0ea81 AK |
789 | entries = 1; |
790 | } | |
bd0f0717 | 791 | |
054f5e69 ZW |
792 | /* This loop counts down so that the chain will be in ascending |
793 | memory order. */ | |
25f0ea81 | 794 | for (i = entries - 1; i >= 1; i--) |
054f5e69 | 795 | { |
d3bfe4de | 796 | e = XCNEWVAR (struct page_entry, page_entry_size); |
ca79429a RH |
797 | e->order = order; |
798 | e->bytes = G.pagesize; | |
799 | e->page = page + (i << G.lg_pagesize); | |
054f5e69 ZW |
800 | e->next = f; |
801 | f = e; | |
802 | } | |
bd0f0717 | 803 | |
054f5e69 | 804 | G.free_pages = f; |
21341cfd | 805 | } |
054f5e69 | 806 | else |
25f0ea81 | 807 | page = alloc_anon (NULL, entry_size, true); |
130fadbb RH |
808 | #endif |
809 | #ifdef USING_MALLOC_PAGE_GROUPS | |
810 | else | |
811 | { | |
812 | /* Allocate a large block of memory and serve out the aligned | |
813 | pages therein. This results in much less memory wastage | |
814 | than the traditional implementation of valloc. */ | |
815 | ||
816 | char *allocation, *a, *enda; | |
817 | size_t alloc_size, head_slop, tail_slop; | |
818 | int multiple_pages = (entry_size == G.pagesize); | |
819 | ||
820 | if (multiple_pages) | |
821 | alloc_size = GGC_QUIRE_SIZE * G.pagesize; | |
822 | else | |
823 | alloc_size = entry_size + G.pagesize - 1; | |
ec4d7730 | 824 | allocation = XNEWVEC (char, alloc_size); |
130fadbb | 825 | |
2a6e6fea | 826 | page = (char *) (((uintptr_t) allocation + G.pagesize - 1) & -G.pagesize); |
130fadbb RH |
827 | head_slop = page - allocation; |
828 | if (multiple_pages) | |
829 | tail_slop = ((size_t) allocation + alloc_size) & (G.pagesize - 1); | |
830 | else | |
831 | tail_slop = alloc_size - entry_size - head_slop; | |
832 | enda = allocation + alloc_size - tail_slop; | |
833 | ||
834 | /* We allocated N pages, which are likely not aligned, leaving | |
835 | us with N-1 usable pages. We plan to place the page_group | |
836 | structure somewhere in the slop. */ | |
837 | if (head_slop >= sizeof (page_group)) | |
838 | group = (page_group *)page - 1; | |
839 | else | |
840 | { | |
841 | /* We magically got an aligned allocation. Too bad, we have | |
842 | to waste a page anyway. */ | |
843 | if (tail_slop == 0) | |
844 | { | |
845 | enda -= G.pagesize; | |
846 | tail_slop += G.pagesize; | |
847 | } | |
282899df | 848 | gcc_assert (tail_slop >= sizeof (page_group)); |
130fadbb RH |
849 | group = (page_group *)enda; |
850 | tail_slop -= sizeof (page_group); | |
851 | } | |
852 | ||
853 | /* Remember that we allocated this memory. */ | |
854 | group->next = G.page_groups; | |
855 | group->allocation = allocation; | |
856 | group->alloc_size = alloc_size; | |
857 | group->in_use = 0; | |
858 | G.page_groups = group; | |
859 | G.bytes_mapped += alloc_size; | |
860 | ||
861 | /* If we allocated multiple pages, put the rest on the free list. */ | |
862 | if (multiple_pages) | |
863 | { | |
864 | struct page_entry *e, *f = G.free_pages; | |
865 | for (a = enda - G.pagesize; a != page; a -= G.pagesize) | |
866 | { | |
ec4d7730 | 867 | e = XCNEWVAR (struct page_entry, page_entry_size); |
130fadbb RH |
868 | e->order = order; |
869 | e->bytes = G.pagesize; | |
870 | e->page = a; | |
871 | e->group = group; | |
872 | e->next = f; | |
873 | f = e; | |
874 | } | |
875 | G.free_pages = f; | |
876 | } | |
877 | } | |
878 | #endif | |
21341cfd AS |
879 | |
880 | if (entry == NULL) | |
d3bfe4de | 881 | entry = XCNEWVAR (struct page_entry, page_entry_size); |
21341cfd AS |
882 | |
883 | entry->bytes = entry_size; | |
884 | entry->page = page; | |
885 | entry->context_depth = G.context_depth; | |
886 | entry->order = order; | |
887 | entry->num_free_objects = num_objects; | |
888 | entry->next_bit_hint = 1; | |
889 | ||
52895e1a RH |
890 | G.context_depth_allocations |= (unsigned long)1 << G.context_depth; |
891 | ||
130fadbb RH |
892 | #ifdef USING_MALLOC_PAGE_GROUPS |
893 | entry->group = group; | |
894 | set_page_group_in_use (group, page); | |
895 | #endif | |
896 | ||
21341cfd AS |
897 | /* Set the one-past-the-end in-use bit. This acts as a sentry as we |
898 | increment the hint. */ | |
899 | entry->in_use_p[num_objects / HOST_BITS_PER_LONG] | |
900 | = (unsigned long) 1 << (num_objects % HOST_BITS_PER_LONG); | |
901 | ||
902 | set_page_table_entry (page, entry); | |
903 | ||
904 | if (GGC_DEBUG_LEVEL >= 2) | |
589005ff | 905 | fprintf (G.debug_file, |
8a951190 | 906 | "Allocating page at %p, object size=%lu, data %p-%p\n", |
20c1dc5e | 907 | (void *) entry, (unsigned long) OBJECT_SIZE (order), page, |
bd0f0717 | 908 | page + entry_size - 1); |
21341cfd AS |
909 | |
910 | return entry; | |
911 | } | |
912 | ||
c4775f82 MS |
913 | /* Adjust the size of G.depth so that no index greater than the one |
914 | used by the top of the G.by_depth is used. */ | |
915 | ||
916 | static inline void | |
20c1dc5e | 917 | adjust_depth (void) |
c4775f82 MS |
918 | { |
919 | page_entry *top; | |
920 | ||
921 | if (G.by_depth_in_use) | |
922 | { | |
923 | top = G.by_depth[G.by_depth_in_use-1]; | |
924 | ||
e0bb17a8 KH |
925 | /* Peel back indices in depth that index into by_depth, so that |
926 | as new elements are added to by_depth, we note the indices | |
c4775f82 MS |
927 | of those elements, if they are for new context depths. */ |
928 | while (G.depth_in_use > (size_t)top->context_depth+1) | |
929 | --G.depth_in_use; | |
930 | } | |
931 | } | |
932 | ||
cb2ec151 | 933 | /* For a page that is no longer needed, put it on the free page list. */ |
21341cfd | 934 | |
685fe032 | 935 | static void |
20c1dc5e | 936 | free_page (page_entry *entry) |
21341cfd AS |
937 | { |
938 | if (GGC_DEBUG_LEVEL >= 2) | |
589005ff | 939 | fprintf (G.debug_file, |
20c1dc5e | 940 | "Deallocating page at %p, data %p-%p\n", (void *) entry, |
21341cfd AS |
941 | entry->page, entry->page + entry->bytes - 1); |
942 | ||
9a0a7d5d HPN |
943 | /* Mark the page as inaccessible. Discard the handle to avoid handle |
944 | leak. */ | |
35dee980 | 945 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (entry->page, entry->bytes)); |
9a0a7d5d | 946 | |
21341cfd AS |
947 | set_page_table_entry (entry->page, NULL); |
948 | ||
130fadbb RH |
949 | #ifdef USING_MALLOC_PAGE_GROUPS |
950 | clear_page_group_in_use (entry->group, entry->page); | |
951 | #endif | |
952 | ||
c4775f82 MS |
953 | if (G.by_depth_in_use > 1) |
954 | { | |
955 | page_entry *top = G.by_depth[G.by_depth_in_use-1]; | |
282899df NS |
956 | int i = entry->index_by_depth; |
957 | ||
958 | /* We cannot free a page from a context deeper than the current | |
959 | one. */ | |
960 | gcc_assert (entry->context_depth == top->context_depth); | |
b8698a0f | 961 | |
282899df NS |
962 | /* Put top element into freed slot. */ |
963 | G.by_depth[i] = top; | |
964 | G.save_in_use[i] = G.save_in_use[G.by_depth_in_use-1]; | |
965 | top->index_by_depth = i; | |
c4775f82 MS |
966 | } |
967 | --G.by_depth_in_use; | |
968 | ||
969 | adjust_depth (); | |
970 | ||
21341cfd AS |
971 | entry->next = G.free_pages; |
972 | G.free_pages = entry; | |
973 | } | |
974 | ||
cb2ec151 | 975 | /* Release the free page cache to the system. */ |
21341cfd | 976 | |
4934cc53 | 977 | static void |
20c1dc5e | 978 | release_pages (void) |
21341cfd | 979 | { |
711a3d82 AK |
980 | #ifdef USING_MADVISE |
981 | page_entry *p, *start_p; | |
982 | char *start; | |
983 | size_t len; | |
d33ef9a5 AK |
984 | size_t mapped_len; |
985 | page_entry *next, *prev, *newprev; | |
986 | size_t free_unit = (GGC_QUIRE_SIZE/2) * G.pagesize; | |
987 | ||
988 | /* First free larger continuous areas to the OS. | |
989 | This allows other allocators to grab these areas if needed. | |
990 | This is only done on larger chunks to avoid fragmentation. | |
991 | This does not always work because the free_pages list is only | |
992 | approximately sorted. */ | |
993 | ||
994 | p = G.free_pages; | |
995 | prev = NULL; | |
996 | while (p) | |
997 | { | |
998 | start = p->page; | |
999 | start_p = p; | |
1000 | len = 0; | |
1001 | mapped_len = 0; | |
1002 | newprev = prev; | |
1003 | while (p && p->page == start + len) | |
1004 | { | |
1005 | len += p->bytes; | |
1006 | if (!p->discarded) | |
1007 | mapped_len += p->bytes; | |
1008 | newprev = p; | |
1009 | p = p->next; | |
1010 | } | |
1011 | if (len >= free_unit) | |
1012 | { | |
1013 | while (start_p != p) | |
1014 | { | |
1015 | next = start_p->next; | |
1016 | free (start_p); | |
1017 | start_p = next; | |
1018 | } | |
1019 | munmap (start, len); | |
1020 | if (prev) | |
1021 | prev->next = p; | |
1022 | else | |
1023 | G.free_pages = p; | |
1024 | G.bytes_mapped -= mapped_len; | |
1025 | continue; | |
1026 | } | |
1027 | prev = newprev; | |
1028 | } | |
1029 | ||
1030 | /* Now give back the fragmented pages to the OS, but keep the address | |
1031 | space to reuse it next time. */ | |
711a3d82 AK |
1032 | |
1033 | for (p = G.free_pages; p; ) | |
1034 | { | |
1035 | if (p->discarded) | |
1036 | { | |
1037 | p = p->next; | |
1038 | continue; | |
1039 | } | |
1040 | start = p->page; | |
1041 | len = p->bytes; | |
1042 | start_p = p; | |
1043 | p = p->next; | |
1044 | while (p && p->page == start + len) | |
1045 | { | |
1046 | len += p->bytes; | |
1047 | p = p->next; | |
1048 | } | |
1049 | /* Give the page back to the kernel, but don't free the mapping. | |
1050 | This avoids fragmentation in the virtual memory map of the | |
1051 | process. Next time we can reuse it by just touching it. */ | |
1052 | madvise (start, len, MADV_DONTNEED); | |
1053 | /* Don't count those pages as mapped to not touch the garbage collector | |
1054 | unnecessarily. */ | |
1055 | G.bytes_mapped -= len; | |
1056 | while (start_p != p) | |
1057 | { | |
1058 | start_p->discarded = true; | |
1059 | start_p = start_p->next; | |
1060 | } | |
1061 | } | |
1062 | #endif | |
1063 | #if defined(USING_MMAP) && !defined(USING_MADVISE) | |
130fadbb | 1064 | page_entry *p, *next; |
21341cfd AS |
1065 | char *start; |
1066 | size_t len; | |
1067 | ||
054f5e69 | 1068 | /* Gather up adjacent pages so they are unmapped together. */ |
21341cfd | 1069 | p = G.free_pages; |
21341cfd AS |
1070 | |
1071 | while (p) | |
1072 | { | |
054f5e69 | 1073 | start = p->page; |
21341cfd | 1074 | next = p->next; |
054f5e69 | 1075 | len = p->bytes; |
21341cfd AS |
1076 | free (p); |
1077 | p = next; | |
21341cfd | 1078 | |
054f5e69 ZW |
1079 | while (p && p->page == start + len) |
1080 | { | |
1081 | next = p->next; | |
1082 | len += p->bytes; | |
1083 | free (p); | |
1084 | p = next; | |
1085 | } | |
1086 | ||
1087 | munmap (start, len); | |
1088 | G.bytes_mapped -= len; | |
1089 | } | |
005537df | 1090 | |
21341cfd | 1091 | G.free_pages = NULL; |
130fadbb RH |
1092 | #endif |
1093 | #ifdef USING_MALLOC_PAGE_GROUPS | |
1094 | page_entry **pp, *p; | |
1095 | page_group **gp, *g; | |
1096 | ||
1097 | /* Remove all pages from free page groups from the list. */ | |
1098 | pp = &G.free_pages; | |
1099 | while ((p = *pp) != NULL) | |
1100 | if (p->group->in_use == 0) | |
1101 | { | |
1102 | *pp = p->next; | |
1103 | free (p); | |
1104 | } | |
1105 | else | |
1106 | pp = &p->next; | |
1107 | ||
1108 | /* Remove all free page groups, and release the storage. */ | |
1109 | gp = &G.page_groups; | |
1110 | while ((g = *gp) != NULL) | |
1111 | if (g->in_use == 0) | |
1112 | { | |
1113 | *gp = g->next; | |
589005ff | 1114 | G.bytes_mapped -= g->alloc_size; |
130fadbb RH |
1115 | free (g->allocation); |
1116 | } | |
1117 | else | |
1118 | gp = &g->next; | |
1119 | #endif | |
21341cfd AS |
1120 | } |
1121 | ||
21341cfd | 1122 | /* This table provides a fast way to determine ceil(log_2(size)) for |
9fd51e67 | 1123 | allocation requests. The minimum allocation size is eight bytes. */ |
6583cf15 NC |
1124 | #define NUM_SIZE_LOOKUP 512 |
1125 | static unsigned char size_lookup[NUM_SIZE_LOOKUP] = | |
9fd51e67 | 1126 | { |
589005ff KH |
1127 | 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, |
1128 | 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, | |
1129 | 5, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, | |
1130 | 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, | |
1131 | 6, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, | |
1132 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, | |
1133 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, | |
21341cfd | 1134 | 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, |
21341cfd AS |
1135 | 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, |
1136 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
1137 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
1138 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
1139 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
1140 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
1141 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
1142 | 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, | |
f5938dcd RG |
1143 | 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, |
1144 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1145 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1146 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1147 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1148 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1149 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1150 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1151 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1152 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1153 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1154 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1155 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1156 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
1157 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, | |
ecf7b86f | 1158 | 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9 |
21341cfd AS |
1159 | }; |
1160 | ||
b9bd6f74 TT |
1161 | /* For a given size of memory requested for allocation, return the |
1162 | actual size that is going to be allocated, as well as the size | |
1163 | order. */ | |
1164 | ||
1165 | static void | |
1166 | ggc_round_alloc_size_1 (size_t requested_size, | |
1167 | size_t *size_order, | |
1168 | size_t *alloced_size) | |
1169 | { | |
1170 | size_t order, object_size; | |
1171 | ||
1172 | if (requested_size < NUM_SIZE_LOOKUP) | |
1173 | { | |
1174 | order = size_lookup[requested_size]; | |
1175 | object_size = OBJECT_SIZE (order); | |
1176 | } | |
1177 | else | |
1178 | { | |
1179 | order = 10; | |
1180 | while (requested_size > (object_size = OBJECT_SIZE (order))) | |
1181 | order++; | |
1182 | } | |
1183 | ||
1184 | if (size_order) | |
1185 | *size_order = order; | |
1186 | if (alloced_size) | |
1187 | *alloced_size = object_size; | |
1188 | } | |
1189 | ||
1190 | /* For a given size of memory requested for allocation, return the | |
1191 | actual size that is going to be allocated. */ | |
1192 | ||
1193 | size_t | |
1194 | ggc_round_alloc_size (size_t requested_size) | |
1195 | { | |
1196 | size_t size = 0; | |
1197 | ||
1198 | ggc_round_alloc_size_1 (requested_size, NULL, &size); | |
1199 | return size; | |
1200 | } | |
1201 | ||
aa40083d | 1202 | /* Allocate a chunk of memory of SIZE bytes. Its contents are undefined. */ |
cb2ec151 | 1203 | |
005537df | 1204 | void * |
a9429e29 | 1205 | ggc_internal_alloc_stat (size_t size MEM_STAT_DECL) |
21341cfd | 1206 | { |
685fe032 | 1207 | size_t order, word, bit, object_offset, object_size; |
21341cfd AS |
1208 | struct page_entry *entry; |
1209 | void *result; | |
1210 | ||
b9bd6f74 | 1211 | ggc_round_alloc_size_1 (size, &order, &object_size); |
21341cfd AS |
1212 | |
1213 | /* If there are non-full pages for this size allocation, they are at | |
1214 | the head of the list. */ | |
1215 | entry = G.pages[order]; | |
1216 | ||
1217 | /* If there is no page for this object size, or all pages in this | |
1218 | context are full, allocate a new page. */ | |
4934cc53 | 1219 | if (entry == NULL || entry->num_free_objects == 0) |
21341cfd AS |
1220 | { |
1221 | struct page_entry *new_entry; | |
1222 | new_entry = alloc_page (order); | |
589005ff | 1223 | |
c4775f82 MS |
1224 | new_entry->index_by_depth = G.by_depth_in_use; |
1225 | push_by_depth (new_entry, 0); | |
1226 | ||
1227 | /* We can skip context depths, if we do, make sure we go all the | |
1228 | way to the new depth. */ | |
1229 | while (new_entry->context_depth >= G.depth_in_use) | |
1230 | push_depth (G.by_depth_in_use-1); | |
1231 | ||
9bf793f9 JL |
1232 | /* If this is the only entry, it's also the tail. If it is not |
1233 | the only entry, then we must update the PREV pointer of the | |
1234 | ENTRY (G.pages[order]) to point to our new page entry. */ | |
21341cfd AS |
1235 | if (entry == NULL) |
1236 | G.page_tails[order] = new_entry; | |
9bf793f9 JL |
1237 | else |
1238 | entry->prev = new_entry; | |
589005ff | 1239 | |
9bf793f9 JL |
1240 | /* Put new pages at the head of the page list. By definition the |
1241 | entry at the head of the list always has a NULL pointer. */ | |
21341cfd | 1242 | new_entry->next = entry; |
9bf793f9 | 1243 | new_entry->prev = NULL; |
21341cfd AS |
1244 | entry = new_entry; |
1245 | G.pages[order] = new_entry; | |
1246 | ||
1247 | /* For a new page, we know the word and bit positions (in the | |
1248 | in_use bitmap) of the first available object -- they're zero. */ | |
1249 | new_entry->next_bit_hint = 1; | |
1250 | word = 0; | |
1251 | bit = 0; | |
1252 | object_offset = 0; | |
1253 | } | |
1254 | else | |
1255 | { | |
1256 | /* First try to use the hint left from the previous allocation | |
1257 | to locate a clear bit in the in-use bitmap. We've made sure | |
1258 | that the one-past-the-end bit is always set, so if the hint | |
1259 | has run over, this test will fail. */ | |
1260 | unsigned hint = entry->next_bit_hint; | |
1261 | word = hint / HOST_BITS_PER_LONG; | |
1262 | bit = hint % HOST_BITS_PER_LONG; | |
589005ff | 1263 | |
21341cfd AS |
1264 | /* If the hint didn't work, scan the bitmap from the beginning. */ |
1265 | if ((entry->in_use_p[word] >> bit) & 1) | |
1266 | { | |
1267 | word = bit = 0; | |
1268 | while (~entry->in_use_p[word] == 0) | |
1269 | ++word; | |
6f0947e4 SB |
1270 | |
1271 | #if GCC_VERSION >= 3004 | |
1272 | bit = __builtin_ctzl (~entry->in_use_p[word]); | |
1273 | #else | |
21341cfd AS |
1274 | while ((entry->in_use_p[word] >> bit) & 1) |
1275 | ++bit; | |
6f0947e4 SB |
1276 | #endif |
1277 | ||
21341cfd AS |
1278 | hint = word * HOST_BITS_PER_LONG + bit; |
1279 | } | |
1280 | ||
1281 | /* Next time, try the next bit. */ | |
1282 | entry->next_bit_hint = hint + 1; | |
1283 | ||
685fe032 | 1284 | object_offset = hint * object_size; |
21341cfd AS |
1285 | } |
1286 | ||
1287 | /* Set the in-use bit. */ | |
1288 | entry->in_use_p[word] |= ((unsigned long) 1 << bit); | |
1289 | ||
1290 | /* Keep a running total of the number of free objects. If this page | |
1291 | fills up, we may have to move it to the end of the list if the | |
1292 | next page isn't full. If the next page is full, all subsequent | |
1293 | pages are full, so there's no need to move it. */ | |
1294 | if (--entry->num_free_objects == 0 | |
1295 | && entry->next != NULL | |
1296 | && entry->next->num_free_objects > 0) | |
1297 | { | |
9bf793f9 | 1298 | /* We have a new head for the list. */ |
21341cfd | 1299 | G.pages[order] = entry->next; |
9bf793f9 JL |
1300 | |
1301 | /* We are moving ENTRY to the end of the page table list. | |
1302 | The new page at the head of the list will have NULL in | |
1303 | its PREV field and ENTRY will have NULL in its NEXT field. */ | |
1304 | entry->next->prev = NULL; | |
21341cfd | 1305 | entry->next = NULL; |
9bf793f9 JL |
1306 | |
1307 | /* Append ENTRY to the tail of the list. */ | |
1308 | entry->prev = G.page_tails[order]; | |
21341cfd AS |
1309 | G.page_tails[order]->next = entry; |
1310 | G.page_tails[order] = entry; | |
1311 | } | |
1312 | ||
1313 | /* Calculate the object's address. */ | |
1314 | result = entry->page + object_offset; | |
7aa6d18a SB |
1315 | if (GATHER_STATISTICS) |
1316 | ggc_record_overhead (OBJECT_SIZE (order), OBJECT_SIZE (order) - size, | |
1317 | result FINAL_PASS_MEM_STAT); | |
21341cfd | 1318 | |
3788cc17 | 1319 | #ifdef ENABLE_GC_CHECKING |
9a0a7d5d HPN |
1320 | /* Keep poisoning-by-writing-0xaf the object, in an attempt to keep the |
1321 | exact same semantics in presence of memory bugs, regardless of | |
1322 | ENABLE_VALGRIND_CHECKING. We override this request below. Drop the | |
1323 | handle to avoid handle leak. */ | |
35dee980 | 1324 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (result, object_size)); |
9a0a7d5d | 1325 | |
f8a83ee3 ZW |
1326 | /* `Poison' the entire allocated object, including any padding at |
1327 | the end. */ | |
685fe032 | 1328 | memset (result, 0xaf, object_size); |
9a0a7d5d HPN |
1329 | |
1330 | /* Make the bytes after the end of the object unaccessible. Discard the | |
1331 | handle to avoid handle leak. */ | |
35dee980 HPN |
1332 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS ((char *) result + size, |
1333 | object_size - size)); | |
21341cfd | 1334 | #endif |
cb2ec151 | 1335 | |
9a0a7d5d HPN |
1336 | /* Tell Valgrind that the memory is there, but its content isn't |
1337 | defined. The bytes at the end of the object are still marked | |
1338 | unaccessible. */ | |
35dee980 | 1339 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (result, size)); |
9a0a7d5d | 1340 | |
21341cfd AS |
1341 | /* Keep track of how many bytes are being allocated. This |
1342 | information is used in deciding when to collect. */ | |
685fe032 | 1343 | G.allocated += object_size; |
21341cfd | 1344 | |
8d18c628 ZD |
1345 | /* For timevar statistics. */ |
1346 | timevar_ggc_mem_total += object_size; | |
1347 | ||
7aa6d18a SB |
1348 | if (GATHER_STATISTICS) |
1349 | { | |
1350 | size_t overhead = object_size - size; | |
adc4adcd | 1351 | |
7aa6d18a SB |
1352 | G.stats.total_overhead += overhead; |
1353 | G.stats.total_allocated += object_size; | |
1354 | G.stats.total_overhead_per_order[order] += overhead; | |
1355 | G.stats.total_allocated_per_order[order] += object_size; | |
adc4adcd | 1356 | |
7aa6d18a SB |
1357 | if (size <= 32) |
1358 | { | |
1359 | G.stats.total_overhead_under32 += overhead; | |
1360 | G.stats.total_allocated_under32 += object_size; | |
1361 | } | |
1362 | if (size <= 64) | |
1363 | { | |
1364 | G.stats.total_overhead_under64 += overhead; | |
1365 | G.stats.total_allocated_under64 += object_size; | |
1366 | } | |
1367 | if (size <= 128) | |
1368 | { | |
1369 | G.stats.total_overhead_under128 += overhead; | |
1370 | G.stats.total_allocated_under128 += object_size; | |
1371 | } | |
1372 | } | |
685fe032 | 1373 | |
21341cfd | 1374 | if (GGC_DEBUG_LEVEL >= 3) |
589005ff | 1375 | fprintf (G.debug_file, |
8a951190 | 1376 | "Allocating object, requested size=%lu, actual=%lu at %p on %p\n", |
685fe032 | 1377 | (unsigned long) size, (unsigned long) object_size, result, |
20c1dc5e | 1378 | (void *) entry); |
21341cfd AS |
1379 | |
1380 | return result; | |
1381 | } | |
1382 | ||
dae4174e TT |
1383 | /* Mark function for strings. */ |
1384 | ||
1385 | void | |
1386 | gt_ggc_m_S (const void *p) | |
1387 | { | |
1388 | page_entry *entry; | |
1389 | unsigned bit, word; | |
1390 | unsigned long mask; | |
1391 | unsigned long offset; | |
1392 | ||
1393 | if (!p || !ggc_allocated_p (p)) | |
1394 | return; | |
1395 | ||
1396 | /* Look up the page on which the object is alloced. . */ | |
1397 | entry = lookup_page_table_entry (p); | |
1398 | gcc_assert (entry); | |
1399 | ||
1400 | /* Calculate the index of the object on the page; this is its bit | |
1401 | position in the in_use_p bitmap. Note that because a char* might | |
1402 | point to the middle of an object, we need special code here to | |
1403 | make sure P points to the start of an object. */ | |
1404 | offset = ((const char *) p - entry->page) % object_size_table[entry->order]; | |
1405 | if (offset) | |
1406 | { | |
1407 | /* Here we've seen a char* which does not point to the beginning | |
1408 | of an allocated object. We assume it points to the middle of | |
1409 | a STRING_CST. */ | |
1410 | gcc_assert (offset == offsetof (struct tree_string, str)); | |
1411 | p = ((const char *) p) - offset; | |
d3bfe4de | 1412 | gt_ggc_mx_lang_tree_node (CONST_CAST (void *, p)); |
dae4174e TT |
1413 | return; |
1414 | } | |
1415 | ||
1416 | bit = OFFSET_TO_BIT (((const char *) p) - entry->page, entry->order); | |
1417 | word = bit / HOST_BITS_PER_LONG; | |
1418 | mask = (unsigned long) 1 << (bit % HOST_BITS_PER_LONG); | |
1419 | ||
1420 | /* If the bit was previously set, skip it. */ | |
1421 | if (entry->in_use_p[word] & mask) | |
1422 | return; | |
1423 | ||
1424 | /* Otherwise set it, and decrement the free object count. */ | |
1425 | entry->in_use_p[word] |= mask; | |
1426 | entry->num_free_objects -= 1; | |
1427 | ||
1428 | if (GGC_DEBUG_LEVEL >= 4) | |
1429 | fprintf (G.debug_file, "Marking %p\n", p); | |
1430 | ||
1431 | return; | |
1432 | } | |
1433 | ||
0823efed DN |
1434 | |
1435 | /* User-callable entry points for marking string X. */ | |
1436 | ||
1437 | void | |
1438 | gt_ggc_mx (const char *& x) | |
1439 | { | |
1440 | gt_ggc_m_S (x); | |
1441 | } | |
1442 | ||
1443 | void | |
1444 | gt_ggc_mx (unsigned char *& x) | |
1445 | { | |
1446 | gt_ggc_m_S (x); | |
1447 | } | |
1448 | ||
1449 | void | |
1450 | gt_ggc_mx (unsigned char& x ATTRIBUTE_UNUSED) | |
1451 | { | |
1452 | } | |
1453 | ||
cb2ec151 | 1454 | /* If P is not marked, marks it and return false. Otherwise return true. |
21341cfd AS |
1455 | P must have been allocated by the GC allocator; it mustn't point to |
1456 | static objects, stack variables, or memory allocated with malloc. */ | |
cb2ec151 | 1457 | |
005537df | 1458 | int |
20c1dc5e | 1459 | ggc_set_mark (const void *p) |
21341cfd AS |
1460 | { |
1461 | page_entry *entry; | |
1462 | unsigned bit, word; | |
1463 | unsigned long mask; | |
1464 | ||
1465 | /* Look up the page on which the object is alloced. If the object | |
1466 | wasn't allocated by the collector, we'll probably die. */ | |
74c937ca | 1467 | entry = lookup_page_table_entry (p); |
282899df | 1468 | gcc_assert (entry); |
21341cfd AS |
1469 | |
1470 | /* Calculate the index of the object on the page; this is its bit | |
1471 | position in the in_use_p bitmap. */ | |
8537ed68 | 1472 | bit = OFFSET_TO_BIT (((const char *) p) - entry->page, entry->order); |
21341cfd AS |
1473 | word = bit / HOST_BITS_PER_LONG; |
1474 | mask = (unsigned long) 1 << (bit % HOST_BITS_PER_LONG); | |
589005ff | 1475 | |
dc297297 | 1476 | /* If the bit was previously set, skip it. */ |
21341cfd AS |
1477 | if (entry->in_use_p[word] & mask) |
1478 | return 1; | |
1479 | ||
1480 | /* Otherwise set it, and decrement the free object count. */ | |
1481 | entry->in_use_p[word] |= mask; | |
1482 | entry->num_free_objects -= 1; | |
1483 | ||
21341cfd AS |
1484 | if (GGC_DEBUG_LEVEL >= 4) |
1485 | fprintf (G.debug_file, "Marking %p\n", p); | |
1486 | ||
1487 | return 0; | |
1488 | } | |
1489 | ||
589005ff | 1490 | /* Return 1 if P has been marked, zero otherwise. |
4c160717 RK |
1491 | P must have been allocated by the GC allocator; it mustn't point to |
1492 | static objects, stack variables, or memory allocated with malloc. */ | |
1493 | ||
1494 | int | |
20c1dc5e | 1495 | ggc_marked_p (const void *p) |
4c160717 RK |
1496 | { |
1497 | page_entry *entry; | |
1498 | unsigned bit, word; | |
1499 | unsigned long mask; | |
1500 | ||
1501 | /* Look up the page on which the object is alloced. If the object | |
1502 | wasn't allocated by the collector, we'll probably die. */ | |
1503 | entry = lookup_page_table_entry (p); | |
282899df | 1504 | gcc_assert (entry); |
4c160717 RK |
1505 | |
1506 | /* Calculate the index of the object on the page; this is its bit | |
1507 | position in the in_use_p bitmap. */ | |
8537ed68 | 1508 | bit = OFFSET_TO_BIT (((const char *) p) - entry->page, entry->order); |
4c160717 RK |
1509 | word = bit / HOST_BITS_PER_LONG; |
1510 | mask = (unsigned long) 1 << (bit % HOST_BITS_PER_LONG); | |
589005ff | 1511 | |
a4b5b2ae | 1512 | return (entry->in_use_p[word] & mask) != 0; |
4c160717 RK |
1513 | } |
1514 | ||
cb2ec151 RH |
1515 | /* Return the size of the gc-able object P. */ |
1516 | ||
3277221c | 1517 | size_t |
20c1dc5e | 1518 | ggc_get_size (const void *p) |
3277221c MM |
1519 | { |
1520 | page_entry *pe = lookup_page_table_entry (p); | |
2be510b8 | 1521 | return OBJECT_SIZE (pe->order); |
3277221c | 1522 | } |
685fe032 RH |
1523 | |
1524 | /* Release the memory for object P. */ | |
1525 | ||
1526 | void | |
1527 | ggc_free (void *p) | |
1528 | { | |
1529 | page_entry *pe = lookup_page_table_entry (p); | |
1530 | size_t order = pe->order; | |
1531 | size_t size = OBJECT_SIZE (order); | |
1532 | ||
7aa6d18a SB |
1533 | if (GATHER_STATISTICS) |
1534 | ggc_free_overhead (p); | |
07724022 | 1535 | |
685fe032 RH |
1536 | if (GGC_DEBUG_LEVEL >= 3) |
1537 | fprintf (G.debug_file, | |
1538 | "Freeing object, actual size=%lu, at %p on %p\n", | |
1539 | (unsigned long) size, p, (void *) pe); | |
1540 | ||
1541 | #ifdef ENABLE_GC_CHECKING | |
1542 | /* Poison the data, to indicate the data is garbage. */ | |
35dee980 | 1543 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (p, size)); |
685fe032 RH |
1544 | memset (p, 0xa5, size); |
1545 | #endif | |
1546 | /* Let valgrind know the object is free. */ | |
35dee980 | 1547 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (p, size)); |
685fe032 RH |
1548 | |
1549 | #ifdef ENABLE_GC_ALWAYS_COLLECT | |
1550 | /* In the completely-anal-checking mode, we do *not* immediately free | |
b8698a0f | 1551 | the data, but instead verify that the data is *actually* not |
685fe032 RH |
1552 | reachable the next time we collect. */ |
1553 | { | |
5ed6ace5 | 1554 | struct free_object *fo = XNEW (struct free_object); |
685fe032 RH |
1555 | fo->object = p; |
1556 | fo->next = G.free_object_list; | |
1557 | G.free_object_list = fo; | |
1558 | } | |
1559 | #else | |
1560 | { | |
1561 | unsigned int bit_offset, word, bit; | |
1562 | ||
1563 | G.allocated -= size; | |
1564 | ||
1565 | /* Mark the object not-in-use. */ | |
1566 | bit_offset = OFFSET_TO_BIT (((const char *) p) - pe->page, order); | |
1567 | word = bit_offset / HOST_BITS_PER_LONG; | |
1568 | bit = bit_offset % HOST_BITS_PER_LONG; | |
1569 | pe->in_use_p[word] &= ~(1UL << bit); | |
1570 | ||
1571 | if (pe->num_free_objects++ == 0) | |
1572 | { | |
9bf793f9 JL |
1573 | page_entry *p, *q; |
1574 | ||
685fe032 RH |
1575 | /* If the page is completely full, then it's supposed to |
1576 | be after all pages that aren't. Since we've freed one | |
1577 | object from a page that was full, we need to move the | |
b8698a0f | 1578 | page to the head of the list. |
685fe032 | 1579 | |
9bf793f9 JL |
1580 | PE is the node we want to move. Q is the previous node |
1581 | and P is the next node in the list. */ | |
1582 | q = pe->prev; | |
685fe032 RH |
1583 | if (q && q->num_free_objects == 0) |
1584 | { | |
1585 | p = pe->next; | |
9bf793f9 | 1586 | |
685fe032 | 1587 | q->next = p; |
9bf793f9 JL |
1588 | |
1589 | /* If PE was at the end of the list, then Q becomes the | |
1590 | new end of the list. If PE was not the end of the | |
1591 | list, then we need to update the PREV field for P. */ | |
685fe032 RH |
1592 | if (!p) |
1593 | G.page_tails[order] = q; | |
9bf793f9 JL |
1594 | else |
1595 | p->prev = q; | |
1596 | ||
1597 | /* Move PE to the head of the list. */ | |
685fe032 | 1598 | pe->next = G.pages[order]; |
9bf793f9 JL |
1599 | pe->prev = NULL; |
1600 | G.pages[order]->prev = pe; | |
685fe032 RH |
1601 | G.pages[order] = pe; |
1602 | } | |
1603 | ||
1604 | /* Reset the hint bit to point to the only free object. */ | |
1605 | pe->next_bit_hint = bit_offset; | |
1606 | } | |
1607 | } | |
1608 | #endif | |
1609 | } | |
21341cfd | 1610 | \f |
8537ed68 ZW |
1611 | /* Subroutine of init_ggc which computes the pair of numbers used to |
1612 | perform division by OBJECT_SIZE (order) and fills in inverse_table[]. | |
1613 | ||
1614 | This algorithm is taken from Granlund and Montgomery's paper | |
1615 | "Division by Invariant Integers using Multiplication" | |
1616 | (Proc. SIGPLAN PLDI, 1994), section 9 (Exact division by | |
1617 | constants). */ | |
1618 | ||
1619 | static void | |
20c1dc5e | 1620 | compute_inverse (unsigned order) |
8537ed68 | 1621 | { |
b8698a0f | 1622 | size_t size, inv; |
75d75435 | 1623 | unsigned int e; |
280cf02a | 1624 | |
8537ed68 ZW |
1625 | size = OBJECT_SIZE (order); |
1626 | e = 0; | |
1627 | while (size % 2 == 0) | |
1628 | { | |
1629 | e++; | |
1630 | size >>= 1; | |
1631 | } | |
cb2ec151 | 1632 | |
8537ed68 ZW |
1633 | inv = size; |
1634 | while (inv * size != 1) | |
1635 | inv = inv * (2 - inv*size); | |
1636 | ||
1637 | DIV_MULT (order) = inv; | |
1638 | DIV_SHIFT (order) = e; | |
1639 | } | |
1640 | ||
1641 | /* Initialize the ggc-mmap allocator. */ | |
21341cfd | 1642 | void |
20c1dc5e | 1643 | init_ggc (void) |
21341cfd | 1644 | { |
2be510b8 MM |
1645 | unsigned order; |
1646 | ||
c3284718 | 1647 | G.pagesize = getpagesize (); |
21341cfd AS |
1648 | G.lg_pagesize = exact_log2 (G.pagesize); |
1649 | ||
825b6926 | 1650 | #ifdef HAVE_MMAP_DEV_ZERO |
21341cfd AS |
1651 | G.dev_zero_fd = open ("/dev/zero", O_RDONLY); |
1652 | if (G.dev_zero_fd == -1) | |
c770ac2b | 1653 | internal_error ("open /dev/zero: %m"); |
21341cfd AS |
1654 | #endif |
1655 | ||
1656 | #if 0 | |
1657 | G.debug_file = fopen ("ggc-mmap.debug", "w"); | |
1658 | #else | |
1659 | G.debug_file = stdout; | |
1660 | #endif | |
1661 | ||
825b6926 | 1662 | #ifdef USING_MMAP |
1b3e1423 RH |
1663 | /* StunOS has an amazing off-by-one error for the first mmap allocation |
1664 | after fiddling with RLIMIT_STACK. The result, as hard as it is to | |
1665 | believe, is an unaligned page allocation, which would cause us to | |
1666 | hork badly if we tried to use it. */ | |
1667 | { | |
25f0ea81 | 1668 | char *p = alloc_anon (NULL, G.pagesize, true); |
825b6926 | 1669 | struct page_entry *e; |
2a6e6fea | 1670 | if ((uintptr_t)p & (G.pagesize - 1)) |
1b3e1423 RH |
1671 | { |
1672 | /* How losing. Discard this one and try another. If we still | |
1673 | can't get something useful, give up. */ | |
1674 | ||
25f0ea81 | 1675 | p = alloc_anon (NULL, G.pagesize, true); |
2a6e6fea | 1676 | gcc_assert (!((uintptr_t)p & (G.pagesize - 1))); |
1b3e1423 | 1677 | } |
825b6926 | 1678 | |
dc297297 | 1679 | /* We have a good page, might as well hold onto it... */ |
5ed6ace5 | 1680 | e = XCNEW (struct page_entry); |
825b6926 ZW |
1681 | e->bytes = G.pagesize; |
1682 | e->page = p; | |
1683 | e->next = G.free_pages; | |
1684 | G.free_pages = e; | |
1b3e1423 RH |
1685 | } |
1686 | #endif | |
2be510b8 MM |
1687 | |
1688 | /* Initialize the object size table. */ | |
1689 | for (order = 0; order < HOST_BITS_PER_PTR; ++order) | |
1690 | object_size_table[order] = (size_t) 1 << order; | |
1691 | for (order = HOST_BITS_PER_PTR; order < NUM_ORDERS; ++order) | |
b1095f9c MM |
1692 | { |
1693 | size_t s = extra_order_size_table[order - HOST_BITS_PER_PTR]; | |
a469a4f2 RG |
1694 | |
1695 | /* If S is not a multiple of the MAX_ALIGNMENT, then round it up | |
1696 | so that we're sure of getting aligned memory. */ | |
1697 | s = ROUND_UP (s, MAX_ALIGNMENT); | |
b1095f9c MM |
1698 | object_size_table[order] = s; |
1699 | } | |
2be510b8 | 1700 | |
8537ed68 | 1701 | /* Initialize the objects-per-page and inverse tables. */ |
2be510b8 MM |
1702 | for (order = 0; order < NUM_ORDERS; ++order) |
1703 | { | |
1704 | objects_per_page_table[order] = G.pagesize / OBJECT_SIZE (order); | |
1705 | if (objects_per_page_table[order] == 0) | |
1706 | objects_per_page_table[order] = 1; | |
8537ed68 | 1707 | compute_inverse (order); |
2be510b8 MM |
1708 | } |
1709 | ||
1710 | /* Reset the size_lookup array to put appropriately sized objects in | |
1711 | the special orders. All objects bigger than the previous power | |
1712 | of two, but no greater than the special size, should go in the | |
a469a4f2 | 1713 | new order. */ |
2be510b8 MM |
1714 | for (order = HOST_BITS_PER_PTR; order < NUM_ORDERS; ++order) |
1715 | { | |
a469a4f2 RG |
1716 | int o; |
1717 | int i; | |
c4775f82 | 1718 | |
6583cf15 NC |
1719 | i = OBJECT_SIZE (order); |
1720 | if (i >= NUM_SIZE_LOOKUP) | |
1721 | continue; | |
1722 | ||
1723 | for (o = size_lookup[i]; o == size_lookup [i]; --i) | |
a469a4f2 RG |
1724 | size_lookup[i] = order; |
1725 | } | |
ecf7b86f | 1726 | |
c4775f82 MS |
1727 | G.depth_in_use = 0; |
1728 | G.depth_max = 10; | |
5ed6ace5 | 1729 | G.depth = XNEWVEC (unsigned int, G.depth_max); |
c4775f82 MS |
1730 | |
1731 | G.by_depth_in_use = 0; | |
1732 | G.by_depth_max = INITIAL_PTE_COUNT; | |
5ed6ace5 MD |
1733 | G.by_depth = XNEWVEC (page_entry *, G.by_depth_max); |
1734 | G.save_in_use = XNEWVEC (unsigned long *, G.by_depth_max); | |
21341cfd AS |
1735 | } |
1736 | ||
4934cc53 MM |
1737 | /* Merge the SAVE_IN_USE_P and IN_USE_P arrays in P so that IN_USE_P |
1738 | reflects reality. Recalculate NUM_FREE_OBJECTS as well. */ | |
1739 | ||
1740 | static void | |
20c1dc5e | 1741 | ggc_recalculate_in_use_p (page_entry *p) |
4934cc53 MM |
1742 | { |
1743 | unsigned int i; | |
1744 | size_t num_objects; | |
1745 | ||
589005ff | 1746 | /* Because the past-the-end bit in in_use_p is always set, we |
4934cc53 | 1747 | pretend there is one additional object. */ |
17211ab5 | 1748 | num_objects = OBJECTS_IN_PAGE (p) + 1; |
4934cc53 MM |
1749 | |
1750 | /* Reset the free object count. */ | |
1751 | p->num_free_objects = num_objects; | |
1752 | ||
1753 | /* Combine the IN_USE_P and SAVE_IN_USE_P arrays. */ | |
589005ff | 1754 | for (i = 0; |
2be510b8 MM |
1755 | i < CEIL (BITMAP_SIZE (num_objects), |
1756 | sizeof (*p->in_use_p)); | |
4934cc53 MM |
1757 | ++i) |
1758 | { | |
1759 | unsigned long j; | |
1760 | ||
1761 | /* Something is in use if it is marked, or if it was in use in a | |
1762 | context further down the context stack. */ | |
c4775f82 | 1763 | p->in_use_p[i] |= save_in_use_p (p)[i]; |
4934cc53 MM |
1764 | |
1765 | /* Decrement the free object count for every object allocated. */ | |
1766 | for (j = p->in_use_p[i]; j; j >>= 1) | |
1767 | p->num_free_objects -= (j & 1); | |
1768 | } | |
1769 | ||
282899df | 1770 | gcc_assert (p->num_free_objects < num_objects); |
4934cc53 | 1771 | } |
21341cfd | 1772 | \f |
cb2ec151 RH |
1773 | /* Unmark all objects. */ |
1774 | ||
685fe032 | 1775 | static void |
20c1dc5e | 1776 | clear_marks (void) |
21341cfd AS |
1777 | { |
1778 | unsigned order; | |
1779 | ||
2be510b8 | 1780 | for (order = 2; order < NUM_ORDERS; order++) |
21341cfd | 1781 | { |
21341cfd AS |
1782 | page_entry *p; |
1783 | ||
1784 | for (p = G.pages[order]; p != NULL; p = p->next) | |
1785 | { | |
17211ab5 GK |
1786 | size_t num_objects = OBJECTS_IN_PAGE (p); |
1787 | size_t bitmap_size = BITMAP_SIZE (num_objects + 1); | |
1788 | ||
21341cfd | 1789 | /* The data should be page-aligned. */ |
2a6e6fea | 1790 | gcc_assert (!((uintptr_t) p->page & (G.pagesize - 1))); |
21341cfd AS |
1791 | |
1792 | /* Pages that aren't in the topmost context are not collected; | |
1793 | nevertheless, we need their in-use bit vectors to store GC | |
1794 | marks. So, back them up first. */ | |
4934cc53 | 1795 | if (p->context_depth < G.context_depth) |
21341cfd | 1796 | { |
c4775f82 | 1797 | if (! save_in_use_p (p)) |
d3bfe4de | 1798 | save_in_use_p (p) = XNEWVAR (unsigned long, bitmap_size); |
c4775f82 | 1799 | memcpy (save_in_use_p (p), p->in_use_p, bitmap_size); |
21341cfd AS |
1800 | } |
1801 | ||
1802 | /* Reset reset the number of free objects and clear the | |
1803 | in-use bits. These will be adjusted by mark_obj. */ | |
1804 | p->num_free_objects = num_objects; | |
1805 | memset (p->in_use_p, 0, bitmap_size); | |
1806 | ||
1807 | /* Make sure the one-past-the-end bit is always set. */ | |
589005ff | 1808 | p->in_use_p[num_objects / HOST_BITS_PER_LONG] |
21341cfd AS |
1809 | = ((unsigned long) 1 << (num_objects % HOST_BITS_PER_LONG)); |
1810 | } | |
1811 | } | |
1812 | } | |
1813 | ||
cb2ec151 RH |
1814 | /* Free all empty pages. Partially empty pages need no attention |
1815 | because the `mark' bit doubles as an `unused' bit. */ | |
1816 | ||
685fe032 | 1817 | static void |
20c1dc5e | 1818 | sweep_pages (void) |
21341cfd AS |
1819 | { |
1820 | unsigned order; | |
1821 | ||
2be510b8 | 1822 | for (order = 2; order < NUM_ORDERS; order++) |
21341cfd AS |
1823 | { |
1824 | /* The last page-entry to consider, regardless of entries | |
1825 | placed at the end of the list. */ | |
1826 | page_entry * const last = G.page_tails[order]; | |
1827 | ||
17211ab5 | 1828 | size_t num_objects; |
054f5e69 | 1829 | size_t live_objects; |
21341cfd AS |
1830 | page_entry *p, *previous; |
1831 | int done; | |
589005ff | 1832 | |
21341cfd AS |
1833 | p = G.pages[order]; |
1834 | if (p == NULL) | |
1835 | continue; | |
1836 | ||
1837 | previous = NULL; | |
1838 | do | |
1839 | { | |
1840 | page_entry *next = p->next; | |
1841 | ||
1842 | /* Loop until all entries have been examined. */ | |
1843 | done = (p == last); | |
20c1dc5e | 1844 | |
17211ab5 | 1845 | num_objects = OBJECTS_IN_PAGE (p); |
21341cfd | 1846 | |
054f5e69 ZW |
1847 | /* Add all live objects on this page to the count of |
1848 | allocated memory. */ | |
1849 | live_objects = num_objects - p->num_free_objects; | |
1850 | ||
2be510b8 | 1851 | G.allocated += OBJECT_SIZE (order) * live_objects; |
054f5e69 | 1852 | |
21341cfd AS |
1853 | /* Only objects on pages in the topmost context should get |
1854 | collected. */ | |
1855 | if (p->context_depth < G.context_depth) | |
1856 | ; | |
1857 | ||
1858 | /* Remove the page if it's empty. */ | |
054f5e69 | 1859 | else if (live_objects == 0) |
21341cfd | 1860 | { |
9bf793f9 JL |
1861 | /* If P was the first page in the list, then NEXT |
1862 | becomes the new first page in the list, otherwise | |
1863 | splice P out of the forward pointers. */ | |
21341cfd AS |
1864 | if (! previous) |
1865 | G.pages[order] = next; | |
1866 | else | |
1867 | previous->next = next; | |
b8698a0f | 1868 | |
9bf793f9 JL |
1869 | /* Splice P out of the back pointers too. */ |
1870 | if (next) | |
1871 | next->prev = previous; | |
21341cfd AS |
1872 | |
1873 | /* Are we removing the last element? */ | |
1874 | if (p == G.page_tails[order]) | |
1875 | G.page_tails[order] = previous; | |
1876 | free_page (p); | |
1877 | p = previous; | |
1878 | } | |
1879 | ||
1880 | /* If the page is full, move it to the end. */ | |
1881 | else if (p->num_free_objects == 0) | |
1882 | { | |
1883 | /* Don't move it if it's already at the end. */ | |
1884 | if (p != G.page_tails[order]) | |
1885 | { | |
1886 | /* Move p to the end of the list. */ | |
1887 | p->next = NULL; | |
9bf793f9 | 1888 | p->prev = G.page_tails[order]; |
21341cfd AS |
1889 | G.page_tails[order]->next = p; |
1890 | ||
1891 | /* Update the tail pointer... */ | |
1892 | G.page_tails[order] = p; | |
1893 | ||
1894 | /* ... and the head pointer, if necessary. */ | |
1895 | if (! previous) | |
1896 | G.pages[order] = next; | |
1897 | else | |
1898 | previous->next = next; | |
9bf793f9 JL |
1899 | |
1900 | /* And update the backpointer in NEXT if necessary. */ | |
1901 | if (next) | |
1902 | next->prev = previous; | |
1903 | ||
21341cfd AS |
1904 | p = previous; |
1905 | } | |
1906 | } | |
1907 | ||
1908 | /* If we've fallen through to here, it's a page in the | |
1909 | topmost context that is neither full nor empty. Such a | |
1910 | page must precede pages at lesser context depth in the | |
1911 | list, so move it to the head. */ | |
1912 | else if (p != G.pages[order]) | |
1913 | { | |
1914 | previous->next = p->next; | |
9bf793f9 JL |
1915 | |
1916 | /* Update the backchain in the next node if it exists. */ | |
1917 | if (p->next) | |
1918 | p->next->prev = previous; | |
1919 | ||
1920 | /* Move P to the head of the list. */ | |
21341cfd | 1921 | p->next = G.pages[order]; |
9bf793f9 JL |
1922 | p->prev = NULL; |
1923 | G.pages[order]->prev = p; | |
1924 | ||
1925 | /* Update the head pointer. */ | |
21341cfd | 1926 | G.pages[order] = p; |
9bf793f9 | 1927 | |
21341cfd AS |
1928 | /* Are we moving the last element? */ |
1929 | if (G.page_tails[order] == p) | |
1930 | G.page_tails[order] = previous; | |
1931 | p = previous; | |
1932 | } | |
1933 | ||
1934 | previous = p; | |
1935 | p = next; | |
589005ff | 1936 | } |
21341cfd | 1937 | while (! done); |
4934cc53 MM |
1938 | |
1939 | /* Now, restore the in_use_p vectors for any pages from contexts | |
1940 | other than the current one. */ | |
1941 | for (p = G.pages[order]; p; p = p->next) | |
1942 | if (p->context_depth != G.context_depth) | |
1943 | ggc_recalculate_in_use_p (p); | |
21341cfd AS |
1944 | } |
1945 | } | |
1946 | ||
3788cc17 | 1947 | #ifdef ENABLE_GC_CHECKING |
cb2ec151 RH |
1948 | /* Clobber all free objects. */ |
1949 | ||
685fe032 | 1950 | static void |
20c1dc5e | 1951 | poison_pages (void) |
21341cfd AS |
1952 | { |
1953 | unsigned order; | |
1954 | ||
2be510b8 | 1955 | for (order = 2; order < NUM_ORDERS; order++) |
21341cfd | 1956 | { |
2be510b8 | 1957 | size_t size = OBJECT_SIZE (order); |
21341cfd AS |
1958 | page_entry *p; |
1959 | ||
1960 | for (p = G.pages[order]; p != NULL; p = p->next) | |
1961 | { | |
17211ab5 | 1962 | size_t num_objects; |
21341cfd | 1963 | size_t i; |
c831fdea MM |
1964 | |
1965 | if (p->context_depth != G.context_depth) | |
1966 | /* Since we don't do any collection for pages in pushed | |
1967 | contexts, there's no need to do any poisoning. And | |
1968 | besides, the IN_USE_P array isn't valid until we pop | |
1969 | contexts. */ | |
1970 | continue; | |
1971 | ||
17211ab5 | 1972 | num_objects = OBJECTS_IN_PAGE (p); |
21341cfd AS |
1973 | for (i = 0; i < num_objects; i++) |
1974 | { | |
1975 | size_t word, bit; | |
1976 | word = i / HOST_BITS_PER_LONG; | |
1977 | bit = i % HOST_BITS_PER_LONG; | |
1978 | if (((p->in_use_p[word] >> bit) & 1) == 0) | |
9a0a7d5d HPN |
1979 | { |
1980 | char *object = p->page + i * size; | |
1981 | ||
1982 | /* Keep poison-by-write when we expect to use Valgrind, | |
1983 | so the exact same memory semantics is kept, in case | |
1984 | there are memory errors. We override this request | |
1985 | below. */ | |
35dee980 HPN |
1986 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (object, |
1987 | size)); | |
9a0a7d5d HPN |
1988 | memset (object, 0xa5, size); |
1989 | ||
1990 | /* Drop the handle to avoid handle leak. */ | |
35dee980 | 1991 | VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (object, size)); |
9a0a7d5d | 1992 | } |
21341cfd AS |
1993 | } |
1994 | } | |
1995 | } | |
1996 | } | |
685fe032 RH |
1997 | #else |
1998 | #define poison_pages() | |
1999 | #endif | |
2000 | ||
2001 | #ifdef ENABLE_GC_ALWAYS_COLLECT | |
2002 | /* Validate that the reportedly free objects actually are. */ | |
2003 | ||
2004 | static void | |
2005 | validate_free_objects (void) | |
2006 | { | |
2007 | struct free_object *f, *next, *still_free = NULL; | |
2008 | ||
2009 | for (f = G.free_object_list; f ; f = next) | |
2010 | { | |
2011 | page_entry *pe = lookup_page_table_entry (f->object); | |
2012 | size_t bit, word; | |
2013 | ||
2014 | bit = OFFSET_TO_BIT ((char *)f->object - pe->page, pe->order); | |
2015 | word = bit / HOST_BITS_PER_LONG; | |
2016 | bit = bit % HOST_BITS_PER_LONG; | |
2017 | next = f->next; | |
2018 | ||
2019 | /* Make certain it isn't visible from any root. Notice that we | |
2020 | do this check before sweep_pages merges save_in_use_p. */ | |
282899df | 2021 | gcc_assert (!(pe->in_use_p[word] & (1UL << bit))); |
685fe032 RH |
2022 | |
2023 | /* If the object comes from an outer context, then retain the | |
2024 | free_object entry, so that we can verify that the address | |
2025 | isn't live on the stack in some outer context. */ | |
2026 | if (pe->context_depth != G.context_depth) | |
2027 | { | |
2028 | f->next = still_free; | |
2029 | still_free = f; | |
2030 | } | |
2031 | else | |
2032 | free (f); | |
2033 | } | |
2034 | ||
2035 | G.free_object_list = still_free; | |
2036 | } | |
2037 | #else | |
2038 | #define validate_free_objects() | |
21341cfd AS |
2039 | #endif |
2040 | ||
cb2ec151 RH |
2041 | /* Top level mark-and-sweep routine. */ |
2042 | ||
21341cfd | 2043 | void |
20c1dc5e | 2044 | ggc_collect (void) |
21341cfd | 2045 | { |
21341cfd AS |
2046 | /* Avoid frequent unnecessary work by skipping collection if the |
2047 | total allocations haven't expanded much since the last | |
2048 | collection. */ | |
19cc0dd4 | 2049 | float allocated_last_gc = |
3788cc17 ZW |
2050 | MAX (G.allocated_last_gc, (size_t)PARAM_VALUE (GGC_MIN_HEAPSIZE) * 1024); |
2051 | ||
19cc0dd4 | 2052 | float min_expand = allocated_last_gc * PARAM_VALUE (GGC_MIN_EXPAND) / 100; |
3788cc17 | 2053 | |
07724022 | 2054 | if (G.allocated < allocated_last_gc + min_expand && !ggc_force_collect) |
21341cfd | 2055 | return; |
21341cfd | 2056 | |
2a9a326b | 2057 | timevar_push (TV_GC); |
21341cfd | 2058 | if (!quiet_flag) |
b9bfacf0 | 2059 | fprintf (stderr, " {GC %luk -> ", (unsigned long) G.allocated / 1024); |
685fe032 RH |
2060 | if (GGC_DEBUG_LEVEL >= 2) |
2061 | fprintf (G.debug_file, "BEGIN COLLECTING\n"); | |
21341cfd | 2062 | |
054f5e69 ZW |
2063 | /* Zero the total allocated bytes. This will be recalculated in the |
2064 | sweep phase. */ | |
21341cfd AS |
2065 | G.allocated = 0; |
2066 | ||
589005ff | 2067 | /* Release the pages we freed the last time we collected, but didn't |
21341cfd AS |
2068 | reuse in the interim. */ |
2069 | release_pages (); | |
2070 | ||
52895e1a RH |
2071 | /* Indicate that we've seen collections at this context depth. */ |
2072 | G.context_depth_collections = ((unsigned long)1 << (G.context_depth + 1)) - 1; | |
2073 | ||
ae2392a9 BS |
2074 | invoke_plugin_callbacks (PLUGIN_GGC_START, NULL); |
2075 | ||
21341cfd AS |
2076 | clear_marks (); |
2077 | ggc_mark_roots (); | |
7aa6d18a SB |
2078 | |
2079 | if (GATHER_STATISTICS) | |
2080 | ggc_prune_overhead_list (); | |
2081 | ||
21341cfd | 2082 | poison_pages (); |
685fe032 | 2083 | validate_free_objects (); |
cb2ec151 RH |
2084 | sweep_pages (); |
2085 | ||
21341cfd AS |
2086 | G.allocated_last_gc = G.allocated; |
2087 | ||
ae2392a9 BS |
2088 | invoke_plugin_callbacks (PLUGIN_GGC_END, NULL); |
2089 | ||
2a9a326b | 2090 | timevar_pop (TV_GC); |
21341cfd | 2091 | |
21341cfd | 2092 | if (!quiet_flag) |
2a9a326b | 2093 | fprintf (stderr, "%luk}", (unsigned long) G.allocated / 1024); |
685fe032 RH |
2094 | if (GGC_DEBUG_LEVEL >= 2) |
2095 | fprintf (G.debug_file, "END COLLECTING\n"); | |
21341cfd | 2096 | } |
3277221c MM |
2097 | |
2098 | /* Print allocation statistics. */ | |
fba0bfd4 ZW |
2099 | #define SCALE(x) ((unsigned long) ((x) < 1024*10 \ |
2100 | ? (x) \ | |
2101 | : ((x) < 1024*1024*10 \ | |
2102 | ? (x) / 1024 \ | |
2103 | : (x) / (1024*1024)))) | |
07724022 | 2104 | #define STAT_LABEL(x) ((x) < 1024*10 ? ' ' : ((x) < 1024*1024*10 ? 'k' : 'M')) |
3277221c MM |
2105 | |
2106 | void | |
20c1dc5e | 2107 | ggc_print_statistics (void) |
3277221c MM |
2108 | { |
2109 | struct ggc_statistics stats; | |
4934cc53 | 2110 | unsigned int i; |
fba0bfd4 | 2111 | size_t total_overhead = 0; |
3277221c MM |
2112 | |
2113 | /* Clear the statistics. */ | |
d219c7f1 | 2114 | memset (&stats, 0, sizeof (stats)); |
589005ff | 2115 | |
3277221c MM |
2116 | /* Make sure collection will really occur. */ |
2117 | G.allocated_last_gc = 0; | |
2118 | ||
2119 | /* Collect and print the statistics common across collectors. */ | |
fba0bfd4 | 2120 | ggc_print_common_statistics (stderr, &stats); |
3277221c | 2121 | |
4934cc53 MM |
2122 | /* Release free pages so that we will not count the bytes allocated |
2123 | there as part of the total allocated memory. */ | |
2124 | release_pages (); | |
2125 | ||
589005ff | 2126 | /* Collect some information about the various sizes of |
3277221c | 2127 | allocation. */ |
439a7e54 DN |
2128 | fprintf (stderr, |
2129 | "Memory still allocated at the end of the compilation process\n"); | |
adc4adcd | 2130 | fprintf (stderr, "%-5s %10s %10s %10s\n", |
9fd51e67 | 2131 | "Size", "Allocated", "Used", "Overhead"); |
2be510b8 | 2132 | for (i = 0; i < NUM_ORDERS; ++i) |
3277221c MM |
2133 | { |
2134 | page_entry *p; | |
2135 | size_t allocated; | |
2136 | size_t in_use; | |
fba0bfd4 | 2137 | size_t overhead; |
3277221c MM |
2138 | |
2139 | /* Skip empty entries. */ | |
2140 | if (!G.pages[i]) | |
2141 | continue; | |
2142 | ||
fba0bfd4 | 2143 | overhead = allocated = in_use = 0; |
3277221c MM |
2144 | |
2145 | /* Figure out the total number of bytes allocated for objects of | |
fba0bfd4 ZW |
2146 | this size, and how many of them are actually in use. Also figure |
2147 | out how much memory the page table is using. */ | |
3277221c MM |
2148 | for (p = G.pages[i]; p; p = p->next) |
2149 | { | |
2150 | allocated += p->bytes; | |
20c1dc5e | 2151 | in_use += |
17211ab5 | 2152 | (OBJECTS_IN_PAGE (p) - p->num_free_objects) * OBJECT_SIZE (i); |
fba0bfd4 ZW |
2153 | |
2154 | overhead += (sizeof (page_entry) - sizeof (long) | |
17211ab5 | 2155 | + BITMAP_SIZE (OBJECTS_IN_PAGE (p) + 1)); |
3277221c | 2156 | } |
8a951190 AJ |
2157 | fprintf (stderr, "%-5lu %10lu%c %10lu%c %10lu%c\n", |
2158 | (unsigned long) OBJECT_SIZE (i), | |
07724022 JH |
2159 | SCALE (allocated), STAT_LABEL (allocated), |
2160 | SCALE (in_use), STAT_LABEL (in_use), | |
2161 | SCALE (overhead), STAT_LABEL (overhead)); | |
fba0bfd4 | 2162 | total_overhead += overhead; |
3277221c | 2163 | } |
8a951190 | 2164 | fprintf (stderr, "%-5s %10lu%c %10lu%c %10lu%c\n", "Total", |
07724022 | 2165 | SCALE (G.bytes_mapped), STAT_LABEL (G.bytes_mapped), |
c3284718 | 2166 | SCALE (G.allocated), STAT_LABEL (G.allocated), |
07724022 | 2167 | SCALE (total_overhead), STAT_LABEL (total_overhead)); |
adc4adcd | 2168 | |
7aa6d18a SB |
2169 | if (GATHER_STATISTICS) |
2170 | { | |
2171 | fprintf (stderr, "\nTotal allocations and overheads during the compilation process\n"); | |
2172 | ||
6edc3e32 | 2173 | fprintf (stderr, "Total Overhead: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a | 2174 | G.stats.total_overhead); |
6edc3e32 | 2175 | fprintf (stderr, "Total Allocated: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a SB |
2176 | G.stats.total_allocated); |
2177 | ||
6edc3e32 | 2178 | fprintf (stderr, "Total Overhead under 32B: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a | 2179 | G.stats.total_overhead_under32); |
6edc3e32 | 2180 | fprintf (stderr, "Total Allocated under 32B: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a | 2181 | G.stats.total_allocated_under32); |
6edc3e32 | 2182 | fprintf (stderr, "Total Overhead under 64B: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a | 2183 | G.stats.total_overhead_under64); |
6edc3e32 | 2184 | fprintf (stderr, "Total Allocated under 64B: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a | 2185 | G.stats.total_allocated_under64); |
6edc3e32 | 2186 | fprintf (stderr, "Total Overhead under 128B: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a | 2187 | G.stats.total_overhead_under128); |
6edc3e32 | 2188 | fprintf (stderr, "Total Allocated under 128B: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a SB |
2189 | G.stats.total_allocated_under128); |
2190 | ||
2191 | for (i = 0; i < NUM_ORDERS; i++) | |
2192 | if (G.stats.total_allocated_per_order[i]) | |
2193 | { | |
6edc3e32 | 2194 | fprintf (stderr, "Total Overhead page size %7lu: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a SB |
2195 | (unsigned long) OBJECT_SIZE (i), |
2196 | G.stats.total_overhead_per_order[i]); | |
6edc3e32 | 2197 | fprintf (stderr, "Total Allocated page size %7lu: %10" HOST_LONG_LONG_FORMAT "d\n", |
7aa6d18a SB |
2198 | (unsigned long) OBJECT_SIZE (i), |
2199 | G.stats.total_allocated_per_order[i]); | |
2200 | } | |
adc4adcd | 2201 | } |
3277221c | 2202 | } |
17211ab5 | 2203 | \f |
24b97832 ILT |
2204 | struct ggc_pch_ondisk |
2205 | { | |
2206 | unsigned totals[NUM_ORDERS]; | |
2207 | }; | |
2208 | ||
17211ab5 GK |
2209 | struct ggc_pch_data |
2210 | { | |
24b97832 | 2211 | struct ggc_pch_ondisk d; |
2a6e6fea | 2212 | uintptr_t base[NUM_ORDERS]; |
17211ab5 GK |
2213 | size_t written[NUM_ORDERS]; |
2214 | }; | |
2215 | ||
2216 | struct ggc_pch_data * | |
20c1dc5e | 2217 | init_ggc_pch (void) |
17211ab5 | 2218 | { |
5ed6ace5 | 2219 | return XCNEW (struct ggc_pch_data); |
17211ab5 GK |
2220 | } |
2221 | ||
20c1dc5e AJ |
2222 | void |
2223 | ggc_pch_count_object (struct ggc_pch_data *d, void *x ATTRIBUTE_UNUSED, | |
cd030c07 | 2224 | size_t size, bool is_string ATTRIBUTE_UNUSED) |
17211ab5 GK |
2225 | { |
2226 | unsigned order; | |
2227 | ||
6583cf15 | 2228 | if (size < NUM_SIZE_LOOKUP) |
17211ab5 GK |
2229 | order = size_lookup[size]; |
2230 | else | |
2231 | { | |
f5938dcd | 2232 | order = 10; |
17211ab5 GK |
2233 | while (size > OBJECT_SIZE (order)) |
2234 | order++; | |
2235 | } | |
20c1dc5e | 2236 | |
17211ab5 GK |
2237 | d->d.totals[order]++; |
2238 | } | |
20c1dc5e | 2239 | |
17211ab5 | 2240 | size_t |
20c1dc5e | 2241 | ggc_pch_total_size (struct ggc_pch_data *d) |
17211ab5 GK |
2242 | { |
2243 | size_t a = 0; | |
2244 | unsigned i; | |
2245 | ||
2246 | for (i = 0; i < NUM_ORDERS; i++) | |
3bc50163 | 2247 | a += PAGE_ALIGN (d->d.totals[i] * OBJECT_SIZE (i)); |
17211ab5 GK |
2248 | return a; |
2249 | } | |
2250 | ||
2251 | void | |
20c1dc5e | 2252 | ggc_pch_this_base (struct ggc_pch_data *d, void *base) |
17211ab5 | 2253 | { |
2a6e6fea | 2254 | uintptr_t a = (uintptr_t) base; |
17211ab5 | 2255 | unsigned i; |
20c1dc5e | 2256 | |
17211ab5 GK |
2257 | for (i = 0; i < NUM_ORDERS; i++) |
2258 | { | |
2259 | d->base[i] = a; | |
3bc50163 | 2260 | a += PAGE_ALIGN (d->d.totals[i] * OBJECT_SIZE (i)); |
17211ab5 GK |
2261 | } |
2262 | } | |
2263 | ||
2264 | ||
2265 | char * | |
20c1dc5e | 2266 | ggc_pch_alloc_object (struct ggc_pch_data *d, void *x ATTRIBUTE_UNUSED, |
cd030c07 | 2267 | size_t size, bool is_string ATTRIBUTE_UNUSED) |
17211ab5 GK |
2268 | { |
2269 | unsigned order; | |
2270 | char *result; | |
20c1dc5e | 2271 | |
6583cf15 | 2272 | if (size < NUM_SIZE_LOOKUP) |
17211ab5 GK |
2273 | order = size_lookup[size]; |
2274 | else | |
2275 | { | |
f5938dcd | 2276 | order = 10; |
17211ab5 GK |
2277 | while (size > OBJECT_SIZE (order)) |
2278 | order++; | |
2279 | } | |
2280 | ||
2281 | result = (char *) d->base[order]; | |
2282 | d->base[order] += OBJECT_SIZE (order); | |
2283 | return result; | |
2284 | } | |
2285 | ||
20c1dc5e AJ |
2286 | void |
2287 | ggc_pch_prepare_write (struct ggc_pch_data *d ATTRIBUTE_UNUSED, | |
2288 | FILE *f ATTRIBUTE_UNUSED) | |
17211ab5 GK |
2289 | { |
2290 | /* Nothing to do. */ | |
2291 | } | |
2292 | ||
2293 | void | |
8ed00d76 | 2294 | ggc_pch_write_object (struct ggc_pch_data *d, |
20c1dc5e | 2295 | FILE *f, void *x, void *newx ATTRIBUTE_UNUSED, |
b6f61163 | 2296 | size_t size, bool is_string ATTRIBUTE_UNUSED) |
17211ab5 GK |
2297 | { |
2298 | unsigned order; | |
642324bb | 2299 | static const char emptyBytes[256] = { 0 }; |
17211ab5 | 2300 | |
6583cf15 | 2301 | if (size < NUM_SIZE_LOOKUP) |
17211ab5 GK |
2302 | order = size_lookup[size]; |
2303 | else | |
2304 | { | |
f5938dcd | 2305 | order = 10; |
17211ab5 GK |
2306 | while (size > OBJECT_SIZE (order)) |
2307 | order++; | |
2308 | } | |
20c1dc5e | 2309 | |
17211ab5 | 2310 | if (fwrite (x, size, 1, f) != 1) |
d8a07487 | 2311 | fatal_error ("can%'t write PCH file: %m"); |
17211ab5 | 2312 | |
674c7ef1 | 2313 | /* If SIZE is not the same as OBJECT_SIZE(order), then we need to pad the |
0ee55ad8 | 2314 | object out to OBJECT_SIZE(order). This happens for strings. */ |
674c7ef1 RB |
2315 | |
2316 | if (size != OBJECT_SIZE (order)) | |
2317 | { | |
c3284718 | 2318 | unsigned padding = OBJECT_SIZE (order) - size; |
674c7ef1 RB |
2319 | |
2320 | /* To speed small writes, we use a nulled-out array that's larger | |
2321 | than most padding requests as the source for our null bytes. This | |
2322 | permits us to do the padding with fwrite() rather than fseek(), and | |
3f117656 | 2323 | limits the chance the OS may try to flush any outstanding writes. */ |
c3284718 | 2324 | if (padding <= sizeof (emptyBytes)) |
674c7ef1 RB |
2325 | { |
2326 | if (fwrite (emptyBytes, 1, padding, f) != padding) | |
d8a07487 | 2327 | fatal_error ("can%'t write PCH file"); |
674c7ef1 RB |
2328 | } |
2329 | else | |
2330 | { | |
0ee55ad8 | 2331 | /* Larger than our buffer? Just default to fseek. */ |
674c7ef1 | 2332 | if (fseek (f, padding, SEEK_CUR) != 0) |
d8a07487 | 2333 | fatal_error ("can%'t write PCH file"); |
674c7ef1 RB |
2334 | } |
2335 | } | |
17211ab5 GK |
2336 | |
2337 | d->written[order]++; | |
2338 | if (d->written[order] == d->d.totals[order] | |
2339 | && fseek (f, ROUND_UP_VALUE (d->d.totals[order] * OBJECT_SIZE (order), | |
2340 | G.pagesize), | |
2341 | SEEK_CUR) != 0) | |
d8a07487 | 2342 | fatal_error ("can%'t write PCH file: %m"); |
17211ab5 GK |
2343 | } |
2344 | ||
2345 | void | |
20c1dc5e | 2346 | ggc_pch_finish (struct ggc_pch_data *d, FILE *f) |
17211ab5 GK |
2347 | { |
2348 | if (fwrite (&d->d, sizeof (d->d), 1, f) != 1) | |
d8a07487 | 2349 | fatal_error ("can%'t write PCH file: %m"); |
17211ab5 GK |
2350 | free (d); |
2351 | } | |
2352 | ||
c4775f82 MS |
2353 | /* Move the PCH PTE entries just added to the end of by_depth, to the |
2354 | front. */ | |
2355 | ||
2356 | static void | |
20c1dc5e | 2357 | move_ptes_to_front (int count_old_page_tables, int count_new_page_tables) |
c4775f82 MS |
2358 | { |
2359 | unsigned i; | |
2360 | ||
2361 | /* First, we swap the new entries to the front of the varrays. */ | |
2362 | page_entry **new_by_depth; | |
2363 | unsigned long **new_save_in_use; | |
2364 | ||
5ed6ace5 MD |
2365 | new_by_depth = XNEWVEC (page_entry *, G.by_depth_max); |
2366 | new_save_in_use = XNEWVEC (unsigned long *, G.by_depth_max); | |
c4775f82 MS |
2367 | |
2368 | memcpy (&new_by_depth[0], | |
2369 | &G.by_depth[count_old_page_tables], | |
2370 | count_new_page_tables * sizeof (void *)); | |
2371 | memcpy (&new_by_depth[count_new_page_tables], | |
2372 | &G.by_depth[0], | |
2373 | count_old_page_tables * sizeof (void *)); | |
2374 | memcpy (&new_save_in_use[0], | |
2375 | &G.save_in_use[count_old_page_tables], | |
2376 | count_new_page_tables * sizeof (void *)); | |
2377 | memcpy (&new_save_in_use[count_new_page_tables], | |
2378 | &G.save_in_use[0], | |
2379 | count_old_page_tables * sizeof (void *)); | |
2380 | ||
2381 | free (G.by_depth); | |
2382 | free (G.save_in_use); | |
20c1dc5e | 2383 | |
c4775f82 MS |
2384 | G.by_depth = new_by_depth; |
2385 | G.save_in_use = new_save_in_use; | |
2386 | ||
2387 | /* Now update all the index_by_depth fields. */ | |
2388 | for (i = G.by_depth_in_use; i > 0; --i) | |
2389 | { | |
2390 | page_entry *p = G.by_depth[i-1]; | |
2391 | p->index_by_depth = i-1; | |
2392 | } | |
2393 | ||
2394 | /* And last, we update the depth pointers in G.depth. The first | |
2395 | entry is already 0, and context 0 entries always start at index | |
2396 | 0, so there is nothing to update in the first slot. We need a | |
2397 | second slot, only if we have old ptes, and if we do, they start | |
2398 | at index count_new_page_tables. */ | |
2399 | if (count_old_page_tables) | |
2400 | push_depth (count_new_page_tables); | |
2401 | } | |
2402 | ||
17211ab5 | 2403 | void |
20c1dc5e | 2404 | ggc_pch_read (FILE *f, void *addr) |
17211ab5 GK |
2405 | { |
2406 | struct ggc_pch_ondisk d; | |
2407 | unsigned i; | |
d3bfe4de | 2408 | char *offs = (char *) addr; |
c4775f82 MS |
2409 | unsigned long count_old_page_tables; |
2410 | unsigned long count_new_page_tables; | |
2411 | ||
2412 | count_old_page_tables = G.by_depth_in_use; | |
2413 | ||
2414 | /* We've just read in a PCH file. So, every object that used to be | |
2415 | allocated is now free. */ | |
17211ab5 | 2416 | clear_marks (); |
c5d6d04a | 2417 | #ifdef ENABLE_GC_CHECKING |
17211ab5 GK |
2418 | poison_pages (); |
2419 | #endif | |
ead8827d LB |
2420 | /* Since we free all the allocated objects, the free list becomes |
2421 | useless. Validate it now, which will also clear it. */ | |
c3284718 | 2422 | validate_free_objects (); |
17211ab5 GK |
2423 | |
2424 | /* No object read from a PCH file should ever be freed. So, set the | |
2425 | context depth to 1, and set the depth of all the currently-allocated | |
2426 | pages to be 1 too. PCH pages will have depth 0. */ | |
282899df | 2427 | gcc_assert (!G.context_depth); |
17211ab5 GK |
2428 | G.context_depth = 1; |
2429 | for (i = 0; i < NUM_ORDERS; i++) | |
2430 | { | |
2431 | page_entry *p; | |
2432 | for (p = G.pages[i]; p != NULL; p = p->next) | |
2433 | p->context_depth = G.context_depth; | |
2434 | } | |
2435 | ||
2436 | /* Allocate the appropriate page-table entries for the pages read from | |
2437 | the PCH file. */ | |
2438 | if (fread (&d, sizeof (d), 1, f) != 1) | |
d8a07487 | 2439 | fatal_error ("can%'t read PCH file: %m"); |
20c1dc5e | 2440 | |
17211ab5 GK |
2441 | for (i = 0; i < NUM_ORDERS; i++) |
2442 | { | |
2443 | struct page_entry *entry; | |
2444 | char *pte; | |
2445 | size_t bytes; | |
2446 | size_t num_objs; | |
2447 | size_t j; | |
c4775f82 | 2448 | |
17211ab5 GK |
2449 | if (d.totals[i] == 0) |
2450 | continue; | |
c4775f82 | 2451 | |
3bc50163 | 2452 | bytes = PAGE_ALIGN (d.totals[i] * OBJECT_SIZE (i)); |
17211ab5 | 2453 | num_objs = bytes / OBJECT_SIZE (i); |
d3bfe4de KG |
2454 | entry = XCNEWVAR (struct page_entry, (sizeof (struct page_entry) |
2455 | - sizeof (long) | |
2456 | + BITMAP_SIZE (num_objs + 1))); | |
17211ab5 GK |
2457 | entry->bytes = bytes; |
2458 | entry->page = offs; | |
2459 | entry->context_depth = 0; | |
2460 | offs += bytes; | |
2461 | entry->num_free_objects = 0; | |
2462 | entry->order = i; | |
2463 | ||
20c1dc5e | 2464 | for (j = 0; |
17211ab5 GK |
2465 | j + HOST_BITS_PER_LONG <= num_objs + 1; |
2466 | j += HOST_BITS_PER_LONG) | |
2467 | entry->in_use_p[j / HOST_BITS_PER_LONG] = -1; | |
2468 | for (; j < num_objs + 1; j++) | |
20c1dc5e | 2469 | entry->in_use_p[j / HOST_BITS_PER_LONG] |
17211ab5 GK |
2470 | |= 1L << (j % HOST_BITS_PER_LONG); |
2471 | ||
20c1dc5e AJ |
2472 | for (pte = entry->page; |
2473 | pte < entry->page + entry->bytes; | |
17211ab5 GK |
2474 | pte += G.pagesize) |
2475 | set_page_table_entry (pte, entry); | |
2476 | ||
2477 | if (G.page_tails[i] != NULL) | |
2478 | G.page_tails[i]->next = entry; | |
2479 | else | |
2480 | G.pages[i] = entry; | |
2481 | G.page_tails[i] = entry; | |
c4775f82 MS |
2482 | |
2483 | /* We start off by just adding all the new information to the | |
2484 | end of the varrays, later, we will move the new information | |
2485 | to the front of the varrays, as the PCH page tables are at | |
2486 | context 0. */ | |
2487 | push_by_depth (entry, 0); | |
17211ab5 GK |
2488 | } |
2489 | ||
c4775f82 MS |
2490 | /* Now, we update the various data structures that speed page table |
2491 | handling. */ | |
2492 | count_new_page_tables = G.by_depth_in_use - count_old_page_tables; | |
2493 | ||
2494 | move_ptes_to_front (count_old_page_tables, count_new_page_tables); | |
2495 | ||
17211ab5 GK |
2496 | /* Update the statistics. */ |
2497 | G.allocated = G.allocated_last_gc = offs - (char *)addr; | |
2498 | } |