2 * Copyright © 2016 Keith Packard <keithp@keithp.com>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation, either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
15 #define AO_LISP_CONST_BITS
20 #ifdef AO_LISP_MAKE_CONST
23 * When building the constant table, it is the
24 * pool for allocations.
28 uint8_t ao_lisp_const[AO_LISP_POOL_CONST] __attribute__((aligned(4)));
29 #define ao_lisp_pool ao_lisp_const
31 #define AO_LISP_POOL AO_LISP_POOL_CONST
35 uint8_t ao_lisp_pool[AO_LISP_POOL + AO_LISP_POOL_EXTRA] __attribute__((aligned(4)));
41 int dbg_mem = DBG_MEM_START;
44 struct ao_lisp_record {
45 struct ao_lisp_record *next;
46 const struct ao_lisp_type *type;
51 static struct ao_lisp_record *record_head, **record_tail;
54 ao_lisp_record_free(struct ao_lisp_record *record)
57 struct ao_lisp_record *next = record->next;
64 ao_lisp_record_reset(void)
66 ao_lisp_record_free(record_head);
68 record_tail = &record_head;
72 ao_lisp_record(const struct ao_lisp_type *type,
76 struct ao_lisp_record *r = malloc(sizeof (struct ao_lisp_record));
83 record_tail = &r->next;
86 static struct ao_lisp_record *
87 ao_lisp_record_save(void)
89 struct ao_lisp_record *r = record_head;
92 record_tail = &record_head;
97 ao_lisp_record_compare(char *where,
98 struct ao_lisp_record *a,
99 struct ao_lisp_record *b)
102 if (a->type != b->type || a->size != b->size) {
103 printf("%s record difers %d %s %d -> %d %s %d\n",
105 MDBG_OFFSET(a->addr),
108 MDBG_OFFSET(b->addr),
117 printf("%s record differs %d %s %d -> NULL\n",
119 MDBG_OFFSET(a->addr),
125 printf("%s record differs NULL -> %d %s %d\n",
127 MDBG_OFFSET(b->addr),
135 #define ao_lisp_record_reset()
138 uint8_t ao_lisp_exception;
140 struct ao_lisp_root {
141 const struct ao_lisp_type *type;
145 static struct ao_lisp_cons *save_cons[2];
146 static char *save_string[2];
147 static ao_poly save_poly[3];
149 static const struct ao_lisp_root ao_lisp_root[] = {
151 .type = &ao_lisp_cons_type,
152 .addr = (void **) &save_cons[0],
155 .type = &ao_lisp_cons_type,
156 .addr = (void **) &save_cons[1],
159 .type = &ao_lisp_string_type,
160 .addr = (void **) &save_string[0],
163 .type = &ao_lisp_string_type,
164 .addr = (void **) &save_string[1],
168 .addr = (void **) &save_poly[0]
172 .addr = (void **) &save_poly[1]
176 .addr = (void **) &save_poly[2]
179 .type = &ao_lisp_atom_type,
180 .addr = (void **) &ao_lisp_atoms
183 .type = &ao_lisp_frame_type,
184 .addr = (void **) &ao_lisp_frame_global,
187 .type = &ao_lisp_frame_type,
188 .addr = (void **) &ao_lisp_frame_current,
191 .type = &ao_lisp_stack_type,
192 .addr = (void **) &ao_lisp_stack,
196 .addr = (void **) &ao_lisp_v,
199 .type = &ao_lisp_cons_type,
200 .addr = (void **) &ao_lisp_read_cons,
203 .type = &ao_lisp_cons_type,
204 .addr = (void **) &ao_lisp_read_cons_tail,
207 .type = &ao_lisp_cons_type,
208 .addr = (void **) &ao_lisp_read_stack,
212 #define AO_LISP_ROOT (sizeof (ao_lisp_root) / sizeof (ao_lisp_root[0]))
214 static const void ** const ao_lisp_cache[] = {
215 (const void **) &ao_lisp_cons_free_list,
216 (const void **) &ao_lisp_stack_free_list,
217 (const void **) &ao_lisp_frame_free_list[0],
218 (const void **) &ao_lisp_frame_free_list[1],
219 (const void **) &ao_lisp_frame_free_list[2],
220 (const void **) &ao_lisp_frame_free_list[3],
221 (const void **) &ao_lisp_frame_free_list[4],
222 (const void **) &ao_lisp_frame_free_list[5],
225 #if AO_LISP_FRAME_FREE != 6
226 #error Unexpected AO_LISP_FRAME_FREE value
229 #define AO_LISP_CACHE (sizeof (ao_lisp_cache) / sizeof (ao_lisp_cache[0]))
231 #define AO_LISP_BUSY_SIZE ((AO_LISP_POOL + 31) / 32)
233 static uint8_t ao_lisp_busy[AO_LISP_BUSY_SIZE];
234 static uint8_t ao_lisp_cons_note[AO_LISP_BUSY_SIZE];
235 static uint8_t ao_lisp_cons_last[AO_LISP_BUSY_SIZE];
236 static uint8_t ao_lisp_cons_noted;
238 uint16_t ao_lisp_top;
240 struct ao_lisp_chunk {
248 #define AO_LISP_NCHUNK 64
250 static struct ao_lisp_chunk ao_lisp_chunk[AO_LISP_NCHUNK];
252 /* Offset of an address within the pool. */
253 static inline uint16_t pool_offset(void *addr) {
255 if (!AO_LISP_IS_POOL(addr))
258 return ((uint8_t *) addr) - ao_lisp_pool;
261 static inline void mark(uint8_t *tag, int offset) {
262 int byte = offset >> 5;
263 int bit = (offset >> 2) & 7;
264 tag[byte] |= (1 << bit);
267 static inline void clear(uint8_t *tag, int offset) {
268 int byte = offset >> 5;
269 int bit = (offset >> 2) & 7;
270 tag[byte] &= ~(1 << bit);
273 static inline int busy(uint8_t *tag, int offset) {
274 int byte = offset >> 5;
275 int bit = (offset >> 2) & 7;
276 return (tag[byte] >> bit) & 1;
279 static inline int min(int a, int b) { return a < b ? a : b; }
280 static inline int max(int a, int b) { return a > b ? a : b; }
282 static inline int limit(int offset) {
283 return min(AO_LISP_POOL, max(offset, 0));
286 static int total_marked;
289 note_cons(uint16_t offset)
291 MDBG_MOVE("note cons %d\n", offset);
292 ao_lisp_cons_noted = 1;
293 mark(ao_lisp_cons_note, offset);
296 static uint16_t chunk_low, chunk_high;
297 static uint16_t chunk_first, chunk_last;
298 static int chunk_busy;
301 note_chunk(uint16_t offset, uint16_t size)
305 if (offset < chunk_low || chunk_high <= offset)
308 /* Binary search for the location */
312 int m = (l + r) >> 1;
313 if (ao_lisp_chunk[m].old_offset < offset)
319 * The correct location is always in 'l', with r = l-1 being
320 * the entry before the right one
324 /* Off the right side */
325 if (l >= AO_LISP_NCHUNK)
328 /* Off the left side */
329 if (l == 0 && chunk_busy && offset > ao_lisp_chunk[0].old_offset)
333 /* Shuffle existing entries right */
334 int end = min(AO_LISP_NCHUNK, chunk_busy + 1);
336 memmove(&ao_lisp_chunk[l+1],
338 (end - (l+1)) * sizeof (struct ao_lisp_chunk));
341 ao_lisp_chunk[l].old_offset = offset;
342 ao_lisp_chunk[l].size = size;
344 /* Increment the number of elements up to the size of the array */
345 if (chunk_busy < AO_LISP_NCHUNK)
348 /* Set the top address if the array is full */
349 if (chunk_busy == AO_LISP_NCHUNK)
350 chunk_high = ao_lisp_chunk[AO_LISP_NCHUNK-1].old_offset +
351 ao_lisp_chunk[AO_LISP_NCHUNK-1].size;
357 memset(ao_lisp_chunk, '\0', sizeof (ao_lisp_chunk));
358 chunk_high = ao_lisp_top;
363 * Walk all referenced objects calling functions on each one
367 walk(int (*visit_addr)(const struct ao_lisp_type *type, void **addr),
368 int (*visit_poly)(ao_poly *p, uint8_t do_note_cons))
373 ao_lisp_record_reset();
374 memset(ao_lisp_busy, '\0', sizeof (ao_lisp_busy));
375 memset(ao_lisp_cons_note, '\0', sizeof (ao_lisp_cons_note));
376 ao_lisp_cons_noted = 0;
377 for (i = 0; i < (int) AO_LISP_ROOT; i++) {
378 if (ao_lisp_root[i].type) {
379 void **a = ao_lisp_root[i].addr, *v;
381 MDBG_MOVE("root ptr %d\n", MDBG_OFFSET(v));
382 visit_addr(ao_lisp_root[i].type, a);
385 ao_poly *a = (ao_poly *) ao_lisp_root[i].addr, p;
387 MDBG_MOVE("root poly %d\n", MDBG_OFFSET(ao_lisp_ref(p)));
392 while (ao_lisp_cons_noted) {
393 memcpy(ao_lisp_cons_last, ao_lisp_cons_note, sizeof (ao_lisp_cons_note));
394 memset(ao_lisp_cons_note, '\0', sizeof (ao_lisp_cons_note));
395 ao_lisp_cons_noted = 0;
396 for (i = 0; i < AO_LISP_POOL; i += 4) {
397 if (busy(ao_lisp_cons_last, i)) {
398 void *v = ao_lisp_pool + i;
399 MDBG_MOVE("root cons %d\n", MDBG_OFFSET(v));
400 visit_addr(&ao_lisp_cons_type, &v);
412 for (i = 0; i < ao_lisp_top; i += 4) {
413 if ((i & 0xff) == 0) {
417 else if ((i & 0x1f) == 0)
419 if (busy(ao_lisp_busy, i))
426 #define DUMP_BUSY() dump_busy()
431 static const struct ao_lisp_type const *ao_lisp_types[AO_LISP_NUM_TYPE] = {
432 [AO_LISP_CONS] = &ao_lisp_cons_type,
433 [AO_LISP_INT] = NULL,
434 [AO_LISP_STRING] = &ao_lisp_string_type,
435 [AO_LISP_OTHER] = (void *) 0x1,
436 [AO_LISP_ATOM] = &ao_lisp_atom_type,
437 [AO_LISP_BUILTIN] = &ao_lisp_builtin_type,
438 [AO_LISP_FRAME] = &ao_lisp_frame_type,
439 [AO_LISP_LAMBDA] = &ao_lisp_lambda_type,
440 [AO_LISP_STACK] = &ao_lisp_stack_type,
444 ao_lisp_mark_ref(const struct ao_lisp_type *type, void **ref)
446 return ao_lisp_mark(type, *ref);
450 ao_lisp_poly_mark_ref(ao_poly *p, uint8_t do_note_cons)
452 return ao_lisp_poly_mark(*p, do_note_cons);
455 int ao_lisp_collects[2];
456 int ao_lisp_freed[2];
457 int ao_lisp_loops[2];
459 int ao_lisp_last_top;
462 ao_lisp_collect(uint8_t style)
471 struct ao_lisp_record *mark_record = NULL, *move_record = NULL;
473 MDBG_MOVE("collect %d\n", ao_lisp_collects);
477 /* The first time through, we're doing a full collect */
478 if (ao_lisp_last_top == 0)
479 style = AO_LISP_COLLECT_FULL;
481 /* Clear references to all caches */
482 for (i = 0; i < (int) AO_LISP_CACHE; i++)
483 *ao_lisp_cache[i] = NULL;
484 if (style == AO_LISP_COLLECT_FULL) {
487 chunk_low = top = ao_lisp_last_top;
491 MDBG_MOVE("move chunks from %d to %d\n", chunk_low, top);
492 /* Find the sizes of the first chunk of objects to move */
494 walk(ao_lisp_mark_ref, ao_lisp_poly_mark_ref);
496 marked = total_marked;
498 ao_lisp_record_free(mark_record);
499 mark_record = ao_lisp_record_save();
500 if (mark_record && move_record)
501 ao_lisp_record_compare("mark", move_record, mark_record);
503 if (moved && moved != marked)
509 /* Find the first moving object */
510 for (i = 0; i < chunk_busy; i++) {
511 uint16_t size = ao_lisp_chunk[i].size;
518 if (ao_lisp_chunk[i].old_offset > top)
521 MDBG_MOVE("chunk %d %d not moving\n",
522 ao_lisp_chunk[i].old_offset,
523 ao_lisp_chunk[i].size);
525 if (ao_lisp_chunk[i].old_offset != top)
532 * Limit amount of chunk array used in mapping moves
533 * to the active region
536 chunk_low = ao_lisp_chunk[i].old_offset;
538 /* Copy all of the objects */
539 for (; i < chunk_busy; i++) {
540 uint16_t size = ao_lisp_chunk[i].size;
547 MDBG_MOVE("chunk %d %d -> %d\n",
548 ao_lisp_chunk[i].old_offset,
551 ao_lisp_chunk[i].new_offset = top;
553 memmove(&ao_lisp_pool[top],
554 &ao_lisp_pool[ao_lisp_chunk[i].old_offset],
562 if (chunk_first < chunk_last) {
563 /* Relocate all references to the objects */
564 walk(ao_lisp_move, ao_lisp_poly_move);
567 ao_lisp_record_free(move_record);
568 move_record = ao_lisp_record_save();
569 if (mark_record && move_record)
570 ao_lisp_record_compare("move", mark_record, move_record);
572 moved = total_marked;
578 /* If we ran into the end of the heap, then
579 * there's no need to keep walking
581 if (chunk_last != AO_LISP_NCHUNK)
584 /* Next loop starts right above this loop */
585 chunk_low = chunk_high;
588 /* Compute amount of memory freed */
589 ret = ao_lisp_top - top;
592 ++ao_lisp_collects[style];
593 ao_lisp_freed[style] += ret;
594 ao_lisp_loops[style] += loops;
597 if (style == AO_LISP_COLLECT_FULL)
598 ao_lisp_last_top = top;
600 MDBG_DO(memset(ao_lisp_chunk, '\0', sizeof (ao_lisp_chunk));
601 walk(ao_lisp_mark_ref, ao_lisp_poly_mark_ref));
607 * Mark interfaces for objects
611 * Note a reference to memory and collect information about a few
612 * object sizes at a time
616 ao_lisp_mark_memory(const struct ao_lisp_type *type, void *addr)
619 if (!AO_LISP_IS_POOL(addr))
622 offset = pool_offset(addr);
623 MDBG_MOVE("mark memory %d\n", MDBG_OFFSET(addr));
624 if (busy(ao_lisp_busy, offset)) {
625 MDBG_MOVE("already marked\n");
628 mark(ao_lisp_busy, offset);
629 note_chunk(offset, ao_lisp_size(type, addr));
634 * Mark an object and all that it refereces
637 ao_lisp_mark(const struct ao_lisp_type *type, void *addr)
640 MDBG_MOVE("mark %d\n", MDBG_OFFSET(addr));
642 ret = ao_lisp_mark_memory(type, addr);
644 MDBG_MOVE("mark recurse\n");
652 * Mark an object, unless it is a cons cell and
653 * do_note_cons is set. In that case, just
654 * set a bit in the cons note array; those
655 * will be marked in a separate pass to avoid
656 * deep recursion in the collector
659 ao_lisp_poly_mark(ao_poly p, uint8_t do_note_cons)
664 type = ao_lisp_poly_base_type(p);
666 if (type == AO_LISP_INT)
669 addr = ao_lisp_ref(p);
670 if (!AO_LISP_IS_POOL(addr))
673 if (type == AO_LISP_CONS && do_note_cons) {
674 note_cons(pool_offset(addr));
677 if (type == AO_LISP_OTHER)
678 type = ao_lisp_other_type(addr);
680 const struct ao_lisp_type *lisp_type = ao_lisp_types[type];
686 return ao_lisp_mark(lisp_type, addr);
691 * Find the current location of an object
692 * based on the original location. For unmoved
693 * objects, this is simple. For moved objects,
698 move_map(uint16_t offset)
702 if (offset < chunk_low || chunk_high <= offset)
705 /* Binary search for the location */
709 int m = (l + r) >> 1;
710 if (ao_lisp_chunk[m].old_offset < offset)
716 if (ao_lisp_chunk[l].old_offset != offset)
719 return ao_lisp_chunk[l].new_offset;
723 ao_lisp_move_memory(const struct ao_lisp_type *type, void **ref)
726 uint16_t offset, orig_offset;
728 if (!AO_LISP_IS_POOL(addr))
733 MDBG_MOVE("move memory %d\n", MDBG_OFFSET(addr));
734 orig_offset = pool_offset(addr);
735 offset = move_map(orig_offset);
736 if (offset != orig_offset) {
737 MDBG_MOVE("update ref %d %d -> %d\n",
738 AO_LISP_IS_POOL(ref) ? MDBG_OFFSET(ref) : -1,
739 orig_offset, offset);
740 *ref = ao_lisp_pool + offset;
742 if (busy(ao_lisp_busy, offset)) {
743 MDBG_MOVE("already moved\n");
746 mark(ao_lisp_busy, offset);
747 MDBG_DO(ao_lisp_record(type, addr, ao_lisp_size(type, addr)));
752 ao_lisp_move(const struct ao_lisp_type *type, void **ref)
755 MDBG_MOVE("move object %d\n", MDBG_OFFSET(*ref));
757 ret = ao_lisp_move_memory(type, ref);
759 MDBG_MOVE("move recurse\n");
767 ao_lisp_poly_move(ao_poly *ref, uint8_t do_note_cons)
773 uint16_t offset, orig_offset;
776 base_type = type = ao_lisp_poly_base_type(p);
778 if (type == AO_LISP_INT)
781 addr = ao_lisp_ref(p);
782 if (!AO_LISP_IS_POOL(addr))
785 orig_offset = pool_offset(addr);
786 offset = move_map(orig_offset);
788 if (type == AO_LISP_CONS && do_note_cons) {
789 note_cons(orig_offset);
792 if (type == AO_LISP_OTHER)
793 type = ao_lisp_other_type(ao_lisp_pool + offset);
795 const struct ao_lisp_type *lisp_type = ao_lisp_types[type];
801 ret = ao_lisp_move(lisp_type, &addr);
804 /* Re-write the poly value */
805 if (offset != orig_offset) {
806 ao_poly np = ao_lisp_poly(ao_lisp_pool + offset, base_type);
807 MDBG_MOVE("poly %d moved %d -> %d\n",
808 type, orig_offset, offset);
816 ao_lisp_validate(void)
819 memset(ao_lisp_chunk, '\0', sizeof (ao_lisp_chunk));
820 walk(ao_lisp_mark_ref, ao_lisp_poly_mark_ref);
828 ao_lisp_alloc(int size)
832 MDBG_DO(++dbg_allocs);
833 MDBG_DO(if (dbg_validate) ao_lisp_validate());
834 size = ao_lisp_size_round(size);
835 if (ao_lisp_top + size > AO_LISP_POOL) {
836 if (ao_lisp_collect(AO_LISP_COLLECT_INCREMENTAL) < size &&
837 ao_lisp_collect(AO_LISP_COLLECT_FULL) < size)
839 ao_lisp_error(AO_LISP_OOM, "out of memory");
843 addr = ao_lisp_pool + ao_lisp_top;
849 ao_lisp_cons_stash(int id, struct ao_lisp_cons *cons)
851 save_cons[id] = cons;
854 struct ao_lisp_cons *
855 ao_lisp_cons_fetch(int id)
857 struct ao_lisp_cons *cons = save_cons[id];
858 save_cons[id] = NULL;
863 ao_lisp_poly_stash(int id, ao_poly poly)
865 save_poly[id] = poly;
869 ao_lisp_poly_fetch(int id)
871 ao_poly poly = save_poly[id];
872 save_poly[id] = AO_LISP_NIL;
877 ao_lisp_string_stash(int id, char *string)
879 save_string[id] = string;
883 ao_lisp_string_fetch(int id)
885 char *string = save_string[id];
886 save_string[id] = NULL;