altos/scheme: rearrange debugging defines
[fw/altos] / src / scheme / ao_scheme_mem.c
1 /*
2  * Copyright © 2016 Keith Packard <keithp@keithp.com>
3  *
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.
8  *
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.
13  */
14
15 #define AO_SCHEME_CONST_BITS
16
17 #include "ao_scheme.h"
18 #include <stdio.h>
19 #include <assert.h>
20
21 #ifdef AO_SCHEME_MAKE_CONST
22
23 /*
24  * When building the constant table, it is the
25  * pool for allocations.
26  */
27
28 #include <stdlib.h>
29 uint8_t ao_scheme_const[AO_SCHEME_POOL_CONST] __attribute__((aligned(4)));
30 #define ao_scheme_pool ao_scheme_const
31 #undef AO_SCHEME_POOL
32 #define AO_SCHEME_POOL AO_SCHEME_POOL_CONST
33
34 #else
35
36 uint8_t ao_scheme_pool[AO_SCHEME_POOL + AO_SCHEME_POOL_EXTRA] __attribute__((aligned(4)));
37
38 #endif
39
40 #ifndef DBG_MEM_STATS
41 #define DBG_MEM_STATS   DBG_MEM
42 #endif
43
44 #define DBG_MEM_STACK   0
45 #if DBG_MEM_STACK
46 char    *mem_collect_stack;
47 int64_t mem_collect_max_depth;
48
49 static void
50 ao_scheme_check_stack(void)
51 {
52         char    x;
53         int64_t depth;
54
55         depth = mem_collect_stack - &x;
56         if (depth > mem_collect_max_depth)
57                 mem_collect_max_depth = depth;
58 }
59
60 static void
61 _ao_scheme_reset_stack(char *x)
62 {
63         mem_collect_stack = x;
64 //      mem_collect_max_depth = 0;
65 }
66 #define ao_scheme_declare_stack char x;
67 #define ao_scheme_reset_stack() _ao_scheme_reset_stack(&x)
68 #else
69 #define ao_scheme_check_stack()
70 #define ao_scheme_declare_stack
71 #define ao_scheme_reset_stack()
72 #endif
73
74 #if DBG_MEM
75 #define DBG_MEM_RECORD  1
76 #endif
77
78 #if DBG_MEM
79 int dbg_move_depth;
80 int dbg_mem = DBG_MEM_START;
81 int dbg_validate = 0;
82 #endif
83
84 #if DBG_MEM_RECORD
85 struct ao_scheme_record {
86         struct ao_scheme_record         *next;
87         const struct ao_scheme_type     *type;
88         void                            *addr;
89         int                             size;
90 };
91
92 static struct ao_scheme_record  *record_head, **record_tail;
93
94 static void
95 ao_scheme_record_free(struct ao_scheme_record *record)
96 {
97         while (record) {
98                 struct ao_scheme_record *next = record->next;
99                 free(record);
100                 record = next;
101         }
102 }
103
104 static void
105 ao_scheme_record_reset(void)
106 {
107         ao_scheme_record_free(record_head);
108         record_head = NULL;
109         record_tail = &record_head;
110 }
111
112 static void
113 ao_scheme_record(const struct ao_scheme_type    *type,
114                void                             *addr,
115                int                              size)
116 {
117         struct ao_scheme_record *r = malloc(sizeof (struct ao_scheme_record));
118
119         r->next = NULL;
120         r->type = type;
121         r->addr = addr;
122         r->size = size;
123         *record_tail = r;
124         record_tail = &r->next;
125 }
126
127 static struct ao_scheme_record *
128 ao_scheme_record_save(void)
129 {
130         struct ao_scheme_record *r = record_head;
131
132         record_head = NULL;
133         record_tail = &record_head;
134         return r;
135 }
136
137 static void
138 ao_scheme_record_compare(const char *where,
139                          struct ao_scheme_record *a,
140                          struct ao_scheme_record *b)
141 {
142         while (a && b) {
143                 if (a->type != b->type || a->size != b->size) {
144                         printf("%s record difers %d %s %d -> %d %s %d\n",
145                                where,
146                                MDBG_OFFSET(a->addr),
147                                a->type->name,
148                                a->size,
149                                MDBG_OFFSET(b->addr),
150                                b->type->name,
151                                b->size);
152                         ao_scheme_abort();
153                 }
154                 a = a->next;
155                 b = b->next;
156         }
157         if (a) {
158                 printf("%s record differs %d %s %d -> NULL\n",
159                        where,
160                        MDBG_OFFSET(a->addr),
161                        a->type->name,
162                        a->size);
163                 ao_scheme_abort();
164         }
165         if (b) {
166                 printf("%s record differs NULL -> %d %s %d\n",
167                        where,
168                        MDBG_OFFSET(b->addr),
169                        b->type->name,
170                        b->size);
171                 ao_scheme_abort();
172         }
173 }
174
175 #else
176 #define ao_scheme_record_reset()
177 #define ao_scheme_record(t,a,s)
178 #endif
179
180 uint8_t ao_scheme_exception;
181
182 struct ao_scheme_root {
183         const struct ao_scheme_type     *type;
184         void                            **addr;
185 };
186
187 static struct ao_scheme_cons    *save_cons[2];
188 static struct ao_scheme_string  *save_string[2];
189 static struct ao_scheme_frame   *save_frame[1];
190 static ao_poly                  save_poly[3];
191
192 static const struct ao_scheme_root      ao_scheme_root[] = {
193         {
194                 .type = &ao_scheme_cons_type,
195                 .addr = (void **) &save_cons[0],
196         },
197         {
198                 .type = &ao_scheme_cons_type,
199                 .addr = (void **) &save_cons[1],
200         },
201         {
202                 .type = &ao_scheme_string_type,
203                 .addr = (void **) &save_string[0],
204         },
205         {
206                 .type = &ao_scheme_string_type,
207                 .addr = (void **) &save_string[1],
208         },
209         {
210                 .type = &ao_scheme_frame_type,
211                 .addr = (void **) &save_frame[0],
212         },
213         {
214                 .type = NULL,
215                 .addr = (void **) (void *) &save_poly[0]
216         },
217         {
218                 .type = NULL,
219                 .addr = (void **) (void *) &save_poly[1]
220         },
221         {
222                 .type = NULL,
223                 .addr = (void **) (void *) &save_poly[2]
224         },
225         {
226                 .type = &ao_scheme_atom_type,
227                 .addr = (void **) &ao_scheme_atoms
228         },
229         {
230                 .type = &ao_scheme_frame_type,
231                 .addr = (void **) &ao_scheme_frame_global,
232         },
233         {
234                 .type = &ao_scheme_frame_type,
235                 .addr = (void **) &ao_scheme_frame_current,
236         },
237         {
238                 .type = &ao_scheme_stack_type,
239                 .addr = (void **) &ao_scheme_stack,
240         },
241         {
242                 .type = NULL,
243                 .addr = (void **) (void *) &ao_scheme_v,
244         },
245         {
246                 .type = &ao_scheme_cons_type,
247                 .addr = (void **) &ao_scheme_read_cons,
248         },
249         {
250                 .type = &ao_scheme_cons_type,
251                 .addr = (void **) &ao_scheme_read_cons_tail,
252         },
253         {
254                 .type = &ao_scheme_cons_type,
255                 .addr = (void **) &ao_scheme_read_stack,
256         },
257 #ifdef AO_SCHEME_MAKE_CONST
258         {
259                 .type = &ao_scheme_bool_type,
260                 .addr = (void **) &ao_scheme_false,
261         },
262         {
263                 .type = &ao_scheme_bool_type,
264                 .addr = (void **) &ao_scheme_true,
265         },
266 #endif
267 };
268
269 #define AO_SCHEME_ROOT  (sizeof (ao_scheme_root) / sizeof (ao_scheme_root[0]))
270
271 static const void ** const ao_scheme_cache[] = {
272         (const void **) &ao_scheme_cons_free_list,
273         (const void **) &ao_scheme_stack_free_list,
274         (const void **) &ao_scheme_frame_free_list[0],
275         (const void **) &ao_scheme_frame_free_list[1],
276         (const void **) &ao_scheme_frame_free_list[2],
277         (const void **) &ao_scheme_frame_free_list[3],
278         (const void **) &ao_scheme_frame_free_list[4],
279         (const void **) &ao_scheme_frame_free_list[5],
280 };
281
282 #if AO_SCHEME_FRAME_FREE != 6
283 #error Unexpected AO_SCHEME_FRAME_FREE value
284 #endif
285
286 #define AO_SCHEME_CACHE (sizeof (ao_scheme_cache) / sizeof (ao_scheme_cache[0]))
287
288 #define AO_SCHEME_BUSY_SIZE     ((AO_SCHEME_POOL + 31) / 32)
289
290 static int      ao_scheme_printing, ao_scheme_print_cleared;
291 #if DBG_MEM
292 static int      ao_scheme_collecting;
293 #endif
294 static uint8_t  ao_scheme_busy[AO_SCHEME_BUSY_SIZE];
295 static uint8_t  ao_scheme_cons_note[AO_SCHEME_BUSY_SIZE];
296 static uint8_t  ao_scheme_cons_last[AO_SCHEME_BUSY_SIZE];
297 static uint8_t  ao_scheme_cons_noted;
298
299 uint16_t        ao_scheme_top;
300
301 struct ao_scheme_chunk {
302         uint16_t                old_offset;
303         union {
304                 uint16_t        size;
305                 uint16_t        new_offset;
306         };
307 };
308
309 #define AO_SCHEME_NCHUNK        64
310
311 static struct ao_scheme_chunk ao_scheme_chunk[AO_SCHEME_NCHUNK];
312
313 /* Offset of an address within the pool. */
314 static inline uint16_t pool_offset(void *addr) {
315 #if DBG_MEM
316         if (!AO_SCHEME_IS_POOL(addr))
317                 ao_scheme_abort();
318 #endif
319         return ((uint8_t *) addr) - ao_scheme_pool;
320 }
321
322 static inline void mark(uint8_t *tag, int offset) {
323         int     byte = offset >> 5;
324         int     bit = (offset >> 2) & 7;
325         ao_scheme_check_stack();
326         tag[byte] |= (1 << bit);
327 }
328
329 static inline void clear(uint8_t *tag, int offset) {
330         int     byte = offset >> 5;
331         int     bit = (offset >> 2) & 7;
332         tag[byte] &= ~(1 << bit);
333 }
334
335 static inline int busy(uint8_t *tag, int offset) {
336         int     byte = offset >> 5;
337         int     bit = (offset >> 2) & 7;
338         return (tag[byte] >> bit) & 1;
339 }
340
341 static inline int min(int a, int b) { return a < b ? a : b; }
342 static inline int max(int a, int b) { return a > b ? a : b; }
343
344 static inline int limit(int offset) {
345         return min(AO_SCHEME_POOL, max(offset, 0));
346 }
347
348 static inline void
349 note_cons(uint16_t offset)
350 {
351         MDBG_MOVE("note cons %d\n", offset);
352         ao_scheme_cons_noted = 1;
353         mark(ao_scheme_cons_note, offset);
354 }
355
356 static uint16_t chunk_low, chunk_high;
357 static uint16_t chunk_first, chunk_last;
358
359 static int
360 find_chunk(uint16_t offset)
361 {
362         int l, r;
363         /* Binary search for the location */
364         l = chunk_first;
365         r = chunk_last - 1;
366         while (l <= r) {
367                 int m = (l + r) >> 1;
368                 if (ao_scheme_chunk[m].old_offset < offset)
369                         l = m + 1;
370                 else
371                         r = m - 1;
372         }
373         return l;
374 }
375
376 static void
377 note_chunk(uint16_t offset, uint16_t size)
378 {
379         int l;
380         int end;
381
382         if (offset < chunk_low || chunk_high <= offset)
383                 return;
384
385         l = find_chunk(offset);
386
387         /*
388          * The correct location is always in 'l', with r = l-1 being
389          * the entry before the right one
390          */
391
392 #if DBG_MEM
393         /* Off the right side */
394         if (l >= AO_SCHEME_NCHUNK)
395                 ao_scheme_abort();
396
397         /* Off the left side */
398         if (l == 0 && chunk_last && offset > ao_scheme_chunk[0].old_offset)
399                 ao_scheme_abort();
400
401         if (l < chunk_last && ao_scheme_chunk[l].old_offset == offset)
402                 ao_scheme_abort();
403 #endif
404
405         /* Shuffle existing entries right */
406         end = min(AO_SCHEME_NCHUNK, chunk_last + 1);
407
408         memmove(&ao_scheme_chunk[l+1],
409                 &ao_scheme_chunk[l],
410                 (end - (l+1)) * sizeof (struct ao_scheme_chunk));
411
412         /* Add new entry */
413         ao_scheme_chunk[l].old_offset = offset;
414         ao_scheme_chunk[l].size = size;
415
416         /* Increment the number of elements up to the size of the array */
417         if (chunk_last < AO_SCHEME_NCHUNK)
418                 chunk_last++;
419
420         /* Set the top address if the array is full */
421         if (chunk_last == AO_SCHEME_NCHUNK)
422                 chunk_high = ao_scheme_chunk[AO_SCHEME_NCHUNK-1].old_offset +
423                         ao_scheme_chunk[AO_SCHEME_NCHUNK-1].size;
424 }
425
426 static void
427 reset_chunks(void)
428 {
429         chunk_high = ao_scheme_top;
430         chunk_last = 0;
431         chunk_first = 0;
432 }
433
434 /*
435  * Walk all referenced objects calling functions on each one
436  */
437
438 static void
439 walk(int (*visit_addr)(const struct ao_scheme_type *type, void **addr),
440      int (*visit_poly)(ao_poly *p, uint8_t do_note_cons))
441 {
442         int i;
443
444         ao_scheme_record_reset();
445         memset(ao_scheme_busy, '\0', sizeof (ao_scheme_busy));
446         memset(ao_scheme_cons_note, '\0', sizeof (ao_scheme_cons_note));
447         ao_scheme_cons_noted = 0;
448         for (i = 0; i < (int) AO_SCHEME_ROOT; i++) {
449                 if (ao_scheme_root[i].type) {
450                         void **a = ao_scheme_root[i].addr, *v;
451                         if (a && (v = *a)) {
452                                 MDBG_MOVE("root ptr %d\n", MDBG_OFFSET(v));
453                                 visit_addr(ao_scheme_root[i].type, a);
454                         }
455                 } else {
456                         ao_poly *a = (ao_poly *) ao_scheme_root[i].addr, p;
457                         if (a && (p = *a)) {
458                                 MDBG_MOVE("root poly %d\n", MDBG_OFFSET(ao_scheme_ref(p)));
459                                 visit_poly(a, 0);
460                         }
461                 }
462         }
463         while (ao_scheme_cons_noted) {
464                 memcpy(ao_scheme_cons_last, ao_scheme_cons_note, sizeof (ao_scheme_cons_note));
465                 memset(ao_scheme_cons_note, '\0', sizeof (ao_scheme_cons_note));
466                 ao_scheme_cons_noted = 0;
467                 for (i = 0; i < AO_SCHEME_POOL; i += 4) {
468                         if (busy(ao_scheme_cons_last, i)) {
469                                 void *v = ao_scheme_pool + i;
470                                 MDBG_MOVE("root cons %d\n", MDBG_OFFSET(v));
471                                 visit_addr(&ao_scheme_cons_type, &v);
472                         }
473                 }
474         }
475 }
476
477 #if MDBG_DUMP
478 static void
479 dump_busy(void)
480 {
481         int     i;
482         printf("busy:");
483         for (i = 0; i < ao_scheme_top; i += 4) {
484                 if ((i & 0xff) == 0) {
485                         printf("\n\t");
486                 }
487                 else if ((i & 0x1f) == 0)
488                         printf(" ");
489                 if (busy(ao_scheme_busy, i))
490                         printf("*");
491                 else
492                         printf("-");
493         }
494         printf ("\n");
495 }
496 #define DUMP_BUSY()     dump_busy()
497 #else
498 #define DUMP_BUSY()
499 #endif
500
501 static const struct ao_scheme_type * const ao_scheme_types[AO_SCHEME_NUM_TYPE] = {
502         [AO_SCHEME_CONS] = &ao_scheme_cons_type,
503         [AO_SCHEME_INT] = NULL,
504 #ifdef AO_SCHEME_FEATURE_BIGINT
505         [AO_SCHEME_BIGINT] = &ao_scheme_bigint_type,
506 #endif
507         [AO_SCHEME_OTHER] = (void *) 0x1,
508         [AO_SCHEME_ATOM] = &ao_scheme_atom_type,
509         [AO_SCHEME_BUILTIN] = &ao_scheme_builtin_type,
510         [AO_SCHEME_FRAME] = &ao_scheme_frame_type,
511         [AO_SCHEME_FRAME_VALS] = &ao_scheme_frame_vals_type,
512         [AO_SCHEME_LAMBDA] = &ao_scheme_lambda_type,
513         [AO_SCHEME_STACK] = &ao_scheme_stack_type,
514         [AO_SCHEME_BOOL] = &ao_scheme_bool_type,
515         [AO_SCHEME_STRING] = &ao_scheme_string_type,
516 #ifdef AO_SCHEME_FEATURE_FLOAT
517         [AO_SCHEME_FLOAT] = &ao_scheme_float_type,
518 #endif
519 #ifdef AO_SCHEME_FEATURE_VECTOR
520         [AO_SCHEME_VECTOR] = &ao_scheme_vector_type,
521 #endif
522 };
523
524 static int
525 ao_scheme_mark(const struct ao_scheme_type *type, void *addr);
526
527 static int
528 ao_scheme_move(const struct ao_scheme_type *type, void **ref);
529
530 static int
531 ao_scheme_mark_ref(const struct ao_scheme_type *type, void **ref)
532 {
533         return ao_scheme_mark(type, *ref);
534 }
535
536 static int
537 ao_scheme_poly_mark_ref(ao_poly *p, uint8_t do_note_cons)
538 {
539         return ao_scheme_poly_mark(*p, do_note_cons);
540 }
541
542 #if DBG_MEM_STATS
543 uint64_t ao_scheme_collects[2];
544 uint64_t ao_scheme_freed[2];
545 uint64_t ao_scheme_loops[2];
546 #endif
547
548 int ao_scheme_last_top;
549 int ao_scheme_collect_counts;
550
551 int
552 ao_scheme_collect(uint8_t style)
553 {
554         ao_scheme_declare_stack
555         int     i;
556         int     top;
557 #if DBG_MEM_STATS
558         int     loops = 0;
559 #endif
560 #if DBG_MEM_RECORD
561         struct ao_scheme_record *mark_record = NULL, *move_record = NULL;
562 #endif
563         MDBG_MOVE("collect %lu\n", ao_scheme_collects[style]);
564
565         MDBG_DO(ao_scheme_frame_write(ao_scheme_frame_poly(ao_scheme_frame_global)));
566         MDBG_DO(++ao_scheme_collecting);
567
568         ao_scheme_reset_stack();
569
570         /* The first time through, we're doing a full collect */
571         if (ao_scheme_last_top == 0)
572                 style = AO_SCHEME_COLLECT_FULL;
573
574         /* One in a while, just do a full collect */
575
576         if (ao_scheme_collect_counts >= 128)
577                 style = AO_SCHEME_COLLECT_FULL;
578
579         if (style == AO_SCHEME_COLLECT_FULL)
580                 ao_scheme_collect_counts = 0;
581
582         /* Clear references to all caches */
583         for (i = 0; i < (int) AO_SCHEME_CACHE; i++)
584                 *ao_scheme_cache[i] = NULL;
585         if (style == AO_SCHEME_COLLECT_FULL) {
586                 chunk_low = top = 0;
587         } else {
588                 chunk_low = top = ao_scheme_last_top;
589         }
590         for (;;) {
591                 MDBG_MOVE("move chunks from %d to %d\n", chunk_low, top);
592                 /* Find the sizes of the first chunk of objects to move */
593                 reset_chunks();
594                 walk(ao_scheme_mark_ref, ao_scheme_poly_mark_ref);
595
596 #if DBG_MEM_RECORD
597                 ao_scheme_record_free(mark_record);
598                 mark_record = ao_scheme_record_save();
599                 if (mark_record && move_record)
600                         ao_scheme_record_compare("mark", move_record, mark_record);
601 #endif
602
603                 DUMP_BUSY();
604
605                 /* Find the first moving object */
606                 for (i = 0; i < chunk_last; i++) {
607                         uint16_t        size = ao_scheme_chunk[i].size;
608 #if DBG_MEM
609                         if (!size)
610                                 ao_scheme_abort();
611 #endif
612
613                         if (ao_scheme_chunk[i].old_offset > top)
614                                 break;
615
616                         MDBG_MOVE("chunk %d %d not moving\n",
617                                   ao_scheme_chunk[i].old_offset,
618                                   ao_scheme_chunk[i].size);
619 #if DBG_MEM
620                         if (ao_scheme_chunk[i].old_offset != top)
621                                 ao_scheme_abort();
622 #endif
623                         top += size;
624                 }
625
626                 /*
627                  * Limit amount of chunk array used in mapping moves
628                  * to the active region
629                  */
630                 chunk_first = i;
631                 chunk_low = ao_scheme_chunk[i].old_offset;
632
633                 /* Copy all of the objects */
634                 for (; i < chunk_last; i++) {
635                         uint16_t        size = ao_scheme_chunk[i].size;
636
637 #if DBG_MEM
638                         if (!size)
639                                 ao_scheme_abort();
640 #endif
641
642                         MDBG_MOVE("chunk %d %d -> %d\n",
643                                   ao_scheme_chunk[i].old_offset,
644                                   size,
645                                   top);
646                         ao_scheme_chunk[i].new_offset = top;
647
648                         memmove(&ao_scheme_pool[top],
649                                 &ao_scheme_pool[ao_scheme_chunk[i].old_offset],
650                                 size);
651
652                         top += size;
653                 }
654
655                 if (chunk_first < chunk_last) {
656                         /* Relocate all references to the objects */
657                         walk(ao_scheme_move, ao_scheme_poly_move);
658
659 #if DBG_MEM_RECORD
660                         ao_scheme_record_free(move_record);
661                         move_record = ao_scheme_record_save();
662                         if (mark_record && move_record)
663                                 ao_scheme_record_compare("move", mark_record, move_record);
664 #endif
665                 }
666
667 #if DBG_MEM_STATS
668                 loops++;
669 #endif
670                 /* If we ran into the end of the heap, then
671                  * there's no need to keep walking
672                  */
673                 if (chunk_last != AO_SCHEME_NCHUNK)
674                         break;
675
676                 /* Next loop starts right above this loop */
677                 chunk_low = chunk_high;
678         }
679
680 #if DBG_MEM_STATS
681         /* Collect stats */
682         ++ao_scheme_collects[style];
683         ao_scheme_freed[style] += ao_scheme_top - top;
684         ao_scheme_loops[style] += loops;
685 #endif
686
687         ao_scheme_top = top;
688         if (style == AO_SCHEME_COLLECT_FULL)
689                 ao_scheme_last_top = top;
690
691         MDBG_DO(memset(ao_scheme_chunk, '\0', sizeof (ao_scheme_chunk));
692                 walk(ao_scheme_mark_ref, ao_scheme_poly_mark_ref));
693
694 #if DBG_MEM_STACK
695         fprintf(stderr, "max collect stack depth %lu\n", mem_collect_max_depth);
696 #endif
697         MDBG_DO(--ao_scheme_collecting);
698         return AO_SCHEME_POOL - ao_scheme_top;
699 }
700
701 #if DBG_FREE_CONS
702 void
703 ao_scheme_cons_check(struct ao_scheme_cons *cons)
704 {
705         ao_poly cdr;
706         int offset;
707
708         chunk_low = 0;
709         reset_chunks();
710         walk(ao_scheme_mark_ref, ao_scheme_poly_mark_ref);
711         while (cons) {
712                 if (!AO_SCHEME_IS_POOL(cons))
713                         break;
714                 offset = pool_offset(cons);
715                 if (busy(ao_scheme_busy, offset)) {
716                         ao_scheme_printf("cons at %p offset %d poly %d is busy\n\t%v\n", cons, offset, ao_scheme_cons_poly(cons), ao_scheme_cons_poly(cons));
717                         abort();
718                 }
719                 cdr = cons->cdr;
720                 if (!ao_scheme_is_pair(cdr))
721                         break;
722                 cons = ao_scheme_poly_cons(cdr);
723         }
724 }
725 #endif
726
727 /*
728  * Mark interfaces for objects
729  */
730
731
732 /*
733  * Note a reference to memory and collect information about a few
734  * object sizes at a time
735  */
736
737 int
738 ao_scheme_mark_memory(const struct ao_scheme_type *type, void *addr)
739 {
740         int offset;
741         if (!AO_SCHEME_IS_POOL(addr))
742                 return 1;
743
744         offset = pool_offset(addr);
745         MDBG_MOVE("mark memory %d\n", MDBG_OFFSET(addr));
746         if (busy(ao_scheme_busy, offset)) {
747                 MDBG_MOVE("already marked\n");
748                 return 1;
749         }
750         mark(ao_scheme_busy, offset);
751         note_chunk(offset, ao_scheme_size(type, addr));
752         return 0;
753 }
754
755 /*
756  * Mark an object and all that it refereces
757  */
758 static int
759 ao_scheme_mark(const struct ao_scheme_type *type, void *addr)
760 {
761         int ret;
762         MDBG_MOVE("mark %d\n", MDBG_OFFSET(addr));
763         MDBG_MOVE_IN();
764         ret = ao_scheme_mark_memory(type, addr);
765         if (!ret) {
766                 MDBG_MOVE("mark recurse\n");
767                 type->mark(addr);
768         }
769         MDBG_MOVE_OUT();
770         return ret;
771 }
772
773 /*
774  * Mark an object, unless it is a cons cell and
775  * do_note_cons is set. In that case, just
776  * set a bit in the cons note array; those
777  * will be marked in a separate pass to avoid
778  * deep recursion in the collector
779  */
780 int
781 ao_scheme_poly_mark(ao_poly p, uint8_t do_note_cons)
782 {
783         uint8_t type;
784         void    *addr;
785         int     ret;
786
787         type = ao_scheme_poly_base_type(p);
788
789         if (type == AO_SCHEME_INT)
790                 return 1;
791
792         addr = ao_scheme_ref(p);
793         if (!AO_SCHEME_IS_POOL(addr))
794                 return 1;
795
796         if (type == AO_SCHEME_CONS && do_note_cons) {
797                 note_cons(pool_offset(addr));
798                 return 1;
799         } else {
800                 const struct ao_scheme_type *lisp_type;
801
802                 if (type == AO_SCHEME_OTHER)
803                         type = ao_scheme_other_type(addr);
804
805                 lisp_type = ao_scheme_types[type];
806 #if DBG_MEM
807                 if (!lisp_type)
808                         ao_scheme_abort();
809 #endif
810
811                 MDBG_MOVE("mark %d\n", MDBG_OFFSET(addr));
812                 MDBG_MOVE_IN();
813                 ret = ao_scheme_mark_memory(lisp_type, addr);
814                 if (!ret) {
815                         MDBG_MOVE("mark recurse\n");
816                         lisp_type->mark(addr);
817                 }
818                 MDBG_MOVE_OUT();
819                 return ret;
820         }
821 }
822
823 /*
824  * Find the current location of an object
825  * based on the original location. For unmoved
826  * objects, this is simple. For moved objects,
827  * go search for it
828  */
829
830 static uint16_t
831 move_map(uint16_t offset)
832 {
833         int             l;
834
835         if (offset < chunk_low || chunk_high <= offset)
836                 return offset;
837
838         l = find_chunk(offset);
839
840 #if DBG_MEM
841         if (ao_scheme_chunk[l].old_offset != offset)
842                 ao_scheme_abort();
843 #endif
844         return ao_scheme_chunk[l].new_offset;
845 }
846
847 int
848 ao_scheme_move_memory(const struct ao_scheme_type *type, void **ref)
849 {
850         void            *addr = *ref;
851         uint16_t        offset, orig_offset;
852
853         if (!AO_SCHEME_IS_POOL(addr))
854                 return 1;
855
856         (void) type;
857
858         MDBG_MOVE("move memory %d\n", MDBG_OFFSET(addr));
859         orig_offset = pool_offset(addr);
860         offset = move_map(orig_offset);
861         if (offset != orig_offset) {
862                 MDBG_MOVE("update ref %d %d -> %d\n",
863                           AO_SCHEME_IS_POOL(ref) ? MDBG_OFFSET(ref) : -1,
864                           orig_offset, offset);
865                 *ref = ao_scheme_pool + offset;
866         }
867         if (busy(ao_scheme_busy, offset)) {
868                 MDBG_MOVE("already moved\n");
869                 return 1;
870         }
871         mark(ao_scheme_busy, offset);
872         ao_scheme_record(type, addr, ao_scheme_size(type, addr));
873         return 0;
874 }
875
876 static int
877 ao_scheme_move(const struct ao_scheme_type *type, void **ref)
878 {
879         int ret;
880         MDBG_MOVE("move object %d\n", MDBG_OFFSET(*ref));
881         MDBG_MOVE_IN();
882         ret = ao_scheme_move_memory(type, ref);
883         if (!ret) {
884                 MDBG_MOVE("move recurse\n");
885                 type->move(*ref);
886         }
887         MDBG_MOVE_OUT();
888         return ret;
889 }
890
891 int
892 ao_scheme_poly_move(ao_poly *ref, uint8_t do_note_cons)
893 {
894         ao_poly         p = *ref;
895         int             ret;
896         void            *addr;
897         uint16_t        offset, orig_offset;
898
899         if (ao_scheme_poly_base_type(p) == AO_SCHEME_INT)
900                 return 1;
901
902         addr = ao_scheme_ref(p);
903         if (!AO_SCHEME_IS_POOL(addr))
904                 return 1;
905
906         orig_offset = pool_offset(addr);
907         offset = move_map(orig_offset);
908
909         if (ao_scheme_poly_base_type(p) == AO_SCHEME_CONS && do_note_cons) {
910                 note_cons(orig_offset);
911                 ret = 1;
912         } else {
913                 uint8_t type = ao_scheme_poly_base_type(p);
914                 const struct ao_scheme_type *lisp_type;
915
916                 if (type == AO_SCHEME_OTHER)
917                         type = ao_scheme_other_type(ao_scheme_pool + offset);
918
919                 lisp_type = ao_scheme_types[type];
920 #if DBG_MEM
921                 if (!lisp_type)
922                         ao_scheme_abort();
923 #endif
924                 /* inline ao_scheme_move to save stack space */
925                 MDBG_MOVE("move object %d\n", MDBG_OFFSET(addr));
926                 MDBG_MOVE_IN();
927                 ret = ao_scheme_move_memory(lisp_type, &addr);
928                 if (!ret) {
929                         MDBG_MOVE("move recurse\n");
930                         lisp_type->move(addr);
931                 }
932                 MDBG_MOVE_OUT();
933         }
934
935         /* Re-write the poly value */
936         if (offset != orig_offset) {
937                 ao_poly np = ao_scheme_poly(ao_scheme_pool + offset, ao_scheme_poly_base_type(p));
938                 MDBG_MOVE("poly %d moved %d -> %d\n",
939                           ao_scheme_poly_type(np), orig_offset, offset);
940                 *ref = np;
941         }
942         return ret;
943 }
944
945 #if DBG_MEM
946 static void
947 ao_scheme_validate(void)
948 {
949         chunk_low = 0;
950         memset(ao_scheme_chunk, '\0', sizeof (ao_scheme_chunk));
951         walk(ao_scheme_mark_ref, ao_scheme_poly_mark_ref);
952 }
953
954 int dbg_allocs;
955
956 #endif
957
958 void *
959 ao_scheme_alloc(int size)
960 {
961         void    *addr;
962
963         MDBG_DO(++dbg_allocs);
964         MDBG_DO(if (dbg_validate) ao_scheme_validate());
965         size = ao_scheme_size_round(size);
966         if (AO_SCHEME_POOL - ao_scheme_top < size &&
967             ao_scheme_collect(AO_SCHEME_COLLECT_INCREMENTAL) < size &&
968             ao_scheme_collect(AO_SCHEME_COLLECT_FULL) < size)
969         {
970                 ao_scheme_error(AO_SCHEME_OOM, "out of memory");
971                 return NULL;
972         }
973         addr = ao_scheme_pool + ao_scheme_top;
974         ao_scheme_top += size;
975         MDBG_MOVE("alloc %d size %d\n", MDBG_OFFSET(addr), size);
976         return addr;
977 }
978
979 void
980 ao_scheme_cons_stash(int id, struct ao_scheme_cons *cons)
981 {
982         assert(save_cons[id] == 0);
983         save_cons[id] = cons;
984 }
985
986 struct ao_scheme_cons *
987 ao_scheme_cons_fetch(int id)
988 {
989         struct ao_scheme_cons *cons = save_cons[id];
990         save_cons[id] = NULL;
991         return cons;
992 }
993
994 void
995 ao_scheme_poly_stash(int id, ao_poly poly)
996 {
997         assert(save_poly[id] == AO_SCHEME_NIL);
998         save_poly[id] = poly;
999 }
1000
1001 ao_poly
1002 ao_scheme_poly_fetch(int id)
1003 {
1004         ao_poly poly = save_poly[id];
1005         save_poly[id] = AO_SCHEME_NIL;
1006         return poly;
1007 }
1008
1009 void
1010 ao_scheme_string_stash(int id, struct ao_scheme_string *string)
1011 {
1012         assert(save_string[id] == NULL);
1013         save_string[id] = string;
1014 }
1015
1016 struct ao_scheme_string *
1017 ao_scheme_string_fetch(int id)
1018 {
1019         struct ao_scheme_string *string = save_string[id];
1020         save_string[id] = NULL;
1021         return string;
1022 }
1023
1024 void
1025 ao_scheme_frame_stash(int id, struct ao_scheme_frame *frame)
1026 {
1027         assert(save_frame[id] == NULL);
1028         save_frame[id] = frame;
1029 }
1030
1031 struct ao_scheme_frame *
1032 ao_scheme_frame_fetch(int id)
1033 {
1034         struct ao_scheme_frame *frame = save_frame[id];
1035         save_frame[id] = NULL;
1036         return frame;
1037 }
1038
1039 int
1040 ao_scheme_print_mark_addr(void *addr)
1041 {
1042         int     offset;
1043
1044 #if DBG_MEM
1045         if (ao_scheme_collecting)
1046                 ao_scheme_abort();
1047 #endif
1048
1049         if (!AO_SCHEME_IS_POOL(addr))
1050                 return 1;
1051
1052         if (!ao_scheme_print_cleared) {
1053                 ao_scheme_print_cleared = 1;
1054                 memset(ao_scheme_busy, '\0', sizeof (ao_scheme_busy));
1055         }
1056         offset = pool_offset(addr);
1057         if (busy(ao_scheme_busy, offset))
1058                 return 1;
1059         mark(ao_scheme_busy, offset);
1060         return 0;
1061 }
1062
1063 int
1064 ao_scheme_print_mark_poly(ao_poly p)
1065 {
1066         uint8_t type = ao_scheme_poly_base_type(p);
1067
1068         if (type == AO_SCHEME_INT)
1069                 return 1;
1070         return ao_scheme_print_mark_addr(ao_scheme_ref(p));
1071 }
1072
1073 /* Notes that printing has started */
1074 void
1075 ao_scheme_print_start(void)
1076 {
1077         ao_scheme_printing++;
1078 }
1079
1080 /* Notes that printing has ended */
1081 void
1082 ao_scheme_print_stop(void)
1083 {
1084         ao_scheme_printing--;
1085         if (ao_scheme_printing == 0)
1086                 ao_scheme_print_cleared = 0;
1087 }