2 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3 * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved.
5 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
6 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
8 * Permission is hereby granted to use or copy this program
9 * for any purpose, provided the above notices are retained on all copies.
10 * Permission to modify the code and to distribute modified code is granted,
11 * provided the above notices are retained, and a notice that the code was
12 * modified is included with the above copyright notice.
14 /* Boehm, February 16, 1996 2:30 pm PST */
20 #if defined(mips) && defined(SYSTYPE_BSD) && defined(sony_news)
21 /* sony RISC NEWS, NEWSOS 4 */
23 /* typedef long ptrdiff_t; -- necessary on some really old systems */
26 #if defined(mips) && defined(SYSTYPE_BSD43)
32 # include <sys/types.h>
33 # include <sys/time.h>
34 # include <sys/resource.h>
42 typedef GC_signed_word signed_word;
45 # include "gcconfig.h"
56 typedef char * ptr_t; /* A generic pointer to which we can add */
57 /* byte displacements. */
58 /* Preferably identical to caddr_t, if it */
63 # if !(defined( sony_news ) )
66 # define VOLATILE volatile
76 #if 0 /* was once defined for AMIGA */
82 /*********************************/
84 /* Definitions for conservative */
87 /*********************************/
89 /*********************************/
91 /* Easily changeable parameters */
93 /*********************************/
95 #define STUBBORN_ALLOC /* Define stubborn allocation primitives */
96 #if defined(SRC_M3) || defined(SMALL_CONFIG)
97 # undef STUBBORN_ALLOC
101 /* #define ALL_INTERIOR_POINTERS */
102 /* Forces all pointers into the interior of an */
103 /* object to be considered valid. Also causes the */
104 /* sizes of all objects to be inflated by at least */
105 /* one byte. This should suffice to guarantee */
106 /* that in the presence of a compiler that does */
107 /* not perform garbage-collector-unsafe */
108 /* optimizations, all portable, strictly ANSI */
109 /* conforming C programs should be safely usable */
110 /* with malloc replaced by GC_malloc and free */
111 /* calls removed. There are several disadvantages: */
112 /* 1. There are probably no interesting, portable, */
113 /* strictly ANSI conforming C programs. */
114 /* 2. This option makes it hard for the collector */
115 /* to allocate space that is not ``pointed to'' */
116 /* by integers, etc. Under SunOS 4.X with a */
117 /* statically linked libc, we empiricaly */
118 /* observed that it would be difficult to */
119 /* allocate individual objects larger than 100K. */
120 /* Even if only smaller objects are allocated, */
121 /* more swap space is likely to be needed. */
122 /* Fortunately, much of this will never be */
124 /* If you can easily avoid using this option, do. */
125 /* If not, try to keep individual objects small. */
127 #define PRINTSTATS /* Print garbage collection statistics */
128 /* For less verbose output, undefine in reclaim.c */
130 #define PRINTTIMES /* Print the amount of time consumed by each garbage */
133 #define PRINTBLOCKS /* Print object sizes associated with heap blocks, */
134 /* whether the objects are atomic or composite, and */
135 /* whether or not the block was found to be empty */
136 /* during the reclaim phase. Typically generates */
137 /* about one screenful per garbage collection. */
152 #if defined(PRINTSTATS) && !defined(GATHERSTATS)
156 #ifdef FINALIZE_ON_DEMAND
157 # define GC_INVOKE_FINALIZERS()
159 # define GC_INVOKE_FINALIZERS() (void)GC_invoke_finalizers()
162 #define MERGE_SIZES /* Round up some object sizes, so that fewer distinct */
163 /* free lists are actually maintained. This applies */
164 /* only to the top level routines in misc.c, not to */
165 /* user generated code that calls GC_allocobj and */
166 /* GC_allocaobj directly. */
167 /* Slows down average programs slightly. May however */
168 /* substantially reduce fragmentation if allocation */
169 /* request sizes are widely scattered. */
170 /* May save significant amounts of space for obj_map */
173 #ifndef OLD_BLOCK_ALLOC
174 /* Macros controlling large block allocation strategy. */
175 # define EXACT_FIRST /* Make a complete pass through the large object */
176 /* free list before splitting a block */
177 # define PRESERVE_LAST /* Do not divide last allocated heap segment */
178 /* unless we would otherwise need to expand the */
182 /* ALIGN_DOUBLE requires MERGE_SIZES at present. */
183 # if defined(ALIGN_DOUBLE) && !defined(MERGE_SIZES)
187 #if defined(ALL_INTERIOR_POINTERS) && !defined(DONT_ADD_BYTE_AT_END)
188 # define ADD_BYTE_AT_END
192 # ifndef LARGE_CONFIG
193 # define MINHINCR 16 /* Minimum heap increment, in blocks of HBLKSIZE */
194 /* Must be multiple of largest page size. */
195 # define MAXHINCR 512 /* Maximum heap increment, in blocks */
198 # define MAXHINCR 4096
201 # define TIME_LIMIT 50 /* We try to keep pause times from exceeding */
202 /* this by much. In milliseconds. */
204 # define BL_LIMIT GC_black_list_spacing
205 /* If we need a block of N bytes, and we have */
206 /* a block of N + BL_LIMIT bytes available, */
207 /* and N > BL_LIMIT, */
208 /* but all possible positions in it are */
209 /* blacklisted, we just use it anyway (and */
210 /* print a warning, if warnings are enabled). */
211 /* This risks subsequently leaking the block */
212 /* due to a false reference. But not using */
213 /* the block risks unreasonable immediate */
216 /*********************************/
218 /* Stack saving for debugging */
220 /*********************************/
222 #ifdef SAVE_CALL_CHAIN
225 * Number of frames and arguments to save in objects allocated by
226 * debugging allocator.
228 # define NFRAMES 6 /* Number of frames to save. Even for */
229 /* alignment reasons. */
230 # define NARGS 2 /* Mumber of arguments to save for each call. */
232 # define NEED_CALLINFO
234 /* Fill in the pc and argument information for up to NFRAMES of my */
235 /* callers. Ignore my frame and my callers frame. */
236 void GC_save_callers (/* struct callinfo info[NFRAMES] */);
238 void GC_print_callers (/* struct callinfo info[NFRAMES] */);
242 # ifdef GC_ADD_CALLER
245 # define NEED_CALLINFO
254 word ci_arg[NARGS]; /* bit-wise complement to avoid retention */
256 # if defined(ALIGN_DOUBLE) && (NFRAMES * (NARGS + 1)) % 2 == 1
257 /* Likely alignment problem. */
264 /*********************************/
266 /* OS interface routines */
268 /*********************************/
274 # define CLOCK_TYPE struct timeval
275 # define GET_TIME(x) { struct rusage rusage; \
276 getrusage (RUSAGE_SELF, &rusage); \
277 x = rusage.ru_utime; }
278 # define MS_TIME_DIFF(a,b) ((double) (a.tv_sec - b.tv_sec) * 1000.0 \
279 + (double) (a.tv_usec - b.tv_usec) / 1000.0)
280 #else /* !BSD_TIME */
282 # if !defined(__STDC__) && defined(SPARC) && defined(SUNOS4)
283 clock_t clock(); /* Not in time.h, where it belongs */
285 # if defined(FREEBSD) && !defined(CLOCKS_PER_SEC)
286 # include <machine/limits.h>
287 # define CLOCKS_PER_SEC CLK_TCK
289 # if !defined(CLOCKS_PER_SEC)
290 # define CLOCKS_PER_SEC 1000000
292 * This is technically a bug in the implementation. ANSI requires that
293 * CLOCKS_PER_SEC be defined. But at least under SunOS4.1.1, it isn't.
294 * Also note that the combination of ANSI C and POSIX is incredibly gross
295 * here. The type clock_t is used by both clock() and times(). But on
296 * some machines these use different notions of a clock tick, CLOCKS_PER_SEC
297 * seems to apply only to clock. Hence we use it here. On many machines,
298 * including SunOS, clock actually uses units of microseconds (which are
299 * not really clock ticks).
302 # define CLOCK_TYPE clock_t
303 # define GET_TIME(x) x = clock()
304 # define MS_TIME_DIFF(a,b) ((unsigned long) \
305 (1000.0*(double)((a)-(b))/(double)CLOCKS_PER_SEC))
306 #endif /* !BSD_TIME */
308 /* We use bzero and bcopy internally. They may not be available. */
309 # if defined(SPARC) && defined(SUNOS4)
310 # define BCOPY_EXISTS
312 # if defined(M68K) && defined(AMIGA)
313 # define BCOPY_EXISTS
315 # if defined(M68K) && defined(NEXT)
316 # define BCOPY_EXISTS
319 # define BCOPY_EXISTS
323 # define BCOPY_EXISTS
326 # ifndef BCOPY_EXISTS
328 # define BCOPY(x,y,n) memcpy(y, x, (size_t)(n))
329 # define BZERO(x,n) memset(x, 0, (size_t)(n))
331 # define BCOPY(x,y,n) bcopy((char *)(x),(char *)(y),(int)(n))
332 # define BZERO(x,n) bzero((char *)(x),(int)(n))
335 /* HBLKSIZE aligned allocation. 0 is taken to mean failure */
336 /* space is assumed to be cleared. */
337 /* In the case os USE_MMAP, the argument must also be a */
338 /* physical page size. */
339 /* GET_MEM is currently not assumed to retrieve 0 filled space, */
340 /* though we should perhaps take advantage of the case in which */
343 char * real_malloc();
344 # define GET_MEM(bytes) HBLKPTR(real_malloc((size_t)bytes + GC_page_size) \
348 void * os2_alloc(size_t bytes);
349 # define GET_MEM(bytes) HBLKPTR((ptr_t)os2_alloc((size_t)bytes \
353 # if defined(AMIGA) || defined(NEXT) || defined(MACOSX) || defined(DOS4GW)
354 # define GET_MEM(bytes) HBLKPTR((size_t) \
355 calloc(1, (size_t)bytes + GC_page_size) \
359 extern ptr_t GC_win32_get_mem();
360 # define GET_MEM(bytes) (struct hblk *)GC_win32_get_mem(bytes)
363 # if defined(USE_TEMPORARY_MEMORY)
364 extern Ptr GC_MacTemporaryNewPtr(size_t size,
365 Boolean clearMemory);
366 # define GET_MEM(bytes) HBLKPTR( \
367 GC_MacTemporaryNewPtr(bytes + GC_page_size, true) \
370 # define GET_MEM(bytes) HBLKPTR( \
371 NewPtrClear(bytes + GC_page_size) + GC_page_size-1)
374 extern ptr_t GC_unix_get_mem();
375 # define GET_MEM(bytes) (struct hblk *)GC_unix_get_mem(bytes)
383 * Mutual exclusion between allocator/collector routines.
384 * Needed if there is more than one allocator thread.
385 * FASTLOCK() is assumed to try to acquire the lock in a cheap and
386 * dirty way that is acceptable for a few instructions, e.g. by
387 * inhibiting preemption. This is assumed to have succeeded only
388 * if a subsequent call to FASTLOCK_SUCCEEDED() returns TRUE.
389 * FASTUNLOCK() is called whether or not FASTLOCK_SUCCEEDED().
390 * If signals cannot be tolerated with the FASTLOCK held, then
391 * FASTLOCK should disable signals. The code executed under
392 * FASTLOCK is otherwise immune to interruption, provided it is
394 * DCL_LOCK_STATE declares any local variables needed by LOCK and UNLOCK
395 * and/or DISABLE_SIGNALS and ENABLE_SIGNALS and/or FASTLOCK.
396 * (There is currently no equivalent for FASTLOCK.)
399 # ifdef PCR_OBSOLETE /* Faster, but broken with multiple lwp's */
400 # include "th/PCR_Th.h"
401 # include "th/PCR_ThCrSec.h"
402 extern struct PCR_Th_MLRep GC_allocate_ml;
403 # define DCL_LOCK_STATE PCR_sigset_t GC_old_sig_mask
404 # define LOCK() PCR_Th_ML_Acquire(&GC_allocate_ml)
405 # define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml)
406 # define FASTLOCK() PCR_ThCrSec_EnterSys()
407 /* Here we cheat (a lot): */
408 # define FASTLOCK_SUCCEEDED() (*(int *)(&GC_allocate_ml) == 0)
409 /* TRUE if nobody currently holds the lock */
410 # define FASTUNLOCK() PCR_ThCrSec_ExitSys()
413 # include <base/PCR_Base.h>
414 # include <th/PCR_Th.h>
415 extern PCR_Th_ML GC_allocate_ml;
416 # define DCL_LOCK_STATE \
417 PCR_ERes GC_fastLockRes; PCR_sigset_t GC_old_sig_mask
418 # define LOCK() PCR_Th_ML_Acquire(&GC_allocate_ml)
419 # define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml)
420 # define FASTLOCK() (GC_fastLockRes = PCR_Th_ML_Try(&GC_allocate_ml))
421 # define FASTLOCK_SUCCEEDED() (GC_fastLockRes == PCR_ERes_okay)
422 # define FASTUNLOCK() {\
423 if( FASTLOCK_SUCCEEDED() ) PCR_Th_ML_Release(&GC_allocate_ml); }
426 extern word RT0u__inCritical;
427 # define LOCK() RT0u__inCritical++
428 # define UNLOCK() RT0u__inCritical--
430 # ifdef SOLARIS_THREADS
433 extern mutex_t GC_allocate_ml;
434 # define LOCK() mutex_lock(&GC_allocate_ml);
435 # define UNLOCK() mutex_unlock(&GC_allocate_ml);
437 # ifdef LINUX_THREADS
438 # include <pthread.h>
440 inline static int GC_test_and_set(volatile unsigned int *addr) {
442 /* Note: the "xchg" instruction does not need a "lock" prefix */
443 __asm__ __volatile__("xchgl %0, %1"
444 : "=r"(oldval), "=m"(*(addr))
445 : "0"(1), "m"(*(addr)));
449 -- > Need implementation of GC_test_and_set()
451 # define GC_clear(addr) (*(addr) = 0)
453 extern volatile unsigned int GC_allocate_lock;
454 /* This is not a mutex because mutexes that obey the (optional) */
455 /* POSIX scheduling rules are subject to convoys in high contention */
456 /* applications. This is basically a spin lock. */
457 extern pthread_t GC_lock_holder;
458 extern void GC_lock(void);
459 /* Allocation lock holder. Only set if acquired by client through */
460 /* GC_call_with_alloc_lock. */
461 # define SET_LOCK_HOLDER() GC_lock_holder = pthread_self()
462 # define NO_THREAD (pthread_t)(-1)
463 # define UNSET_LOCK_HOLDER() GC_lock_holder = NO_THREAD
464 # define I_HOLD_LOCK() (pthread_equal(GC_lock_holder, pthread_self()))
466 # define LOCK() pthread_mutex_lock(&GC_allocate_ml)
467 # define UNLOCK() pthread_mutex_unlock(&GC_allocate_ml)
470 { if (GC_test_and_set(&GC_allocate_lock)) GC_lock(); }
472 GC_clear(&GC_allocate_lock)
474 extern GC_bool GC_collecting;
475 # define ENTER_GC() \
479 # define EXIT_GC() GC_collecting = 0;
480 # endif /* LINUX_THREADS */
481 # if defined(IRIX_THREADS) || defined(IRIX_JDK_THREADS)
482 # include <pthread.h>
485 # if __mips < 3 || !(defined (_ABIN32) || defined(_ABI64)) \
486 || !defined(_COMPILER_VERSION) || _COMPILER_VERSION < 700
487 # define GC_test_and_set(addr, v) test_and_set(addr,v)
489 # define GC_test_and_set(addr, v) __test_and_set(addr,v)
491 extern unsigned long GC_allocate_lock;
492 /* This is not a mutex because mutexes that obey the (optional) */
493 /* POSIX scheduling rules are subject to convoys in high contention */
494 /* applications. This is basically a spin lock. */
495 extern pthread_t GC_lock_holder;
496 extern void GC_lock(void);
497 /* Allocation lock holder. Only set if acquired by client through */
498 /* GC_call_with_alloc_lock. */
499 # define SET_LOCK_HOLDER() GC_lock_holder = pthread_self()
500 # define NO_THREAD (pthread_t)(-1)
501 # define UNSET_LOCK_HOLDER() GC_lock_holder = NO_THREAD
502 # define I_HOLD_LOCK() (pthread_equal(GC_lock_holder, pthread_self()))
504 # define LOCK() pthread_mutex_lock(&GC_allocate_ml)
505 # define UNLOCK() pthread_mutex_unlock(&GC_allocate_ml)
507 # define LOCK() { if (GC_test_and_set(&GC_allocate_lock, 1)) GC_lock(); }
508 # if __mips >= 3 && (defined (_ABIN32) || defined(_ABI64)) \
509 && defined(_COMPILER_VERSION) && _COMPILER_VERSION >= 700
510 # define UNLOCK() __lock_release(&GC_allocate_lock)
512 /* The function call in the following should prevent the */
513 /* compiler from moving assignments to below the UNLOCK. */
514 /* This is probably not necessary for ucode or gcc 2.8. */
515 /* It may be necessary for Ragnarok and future gcc */
517 # define UNLOCK() { GC_noop1(&GC_allocate_lock); \
518 *(volatile unsigned long *)(&GC_allocate_lock) = 0; }
521 extern GC_bool GC_collecting;
522 # define ENTER_GC() \
526 # define EXIT_GC() GC_collecting = 0;
527 # endif /* IRIX_THREADS || IRIX_JDK_THREADS */
528 # ifdef WIN32_THREADS
529 # include <windows.h>
530 GC_API CRITICAL_SECTION GC_allocate_ml;
531 # define LOCK() EnterCriticalSection(&GC_allocate_ml);
532 # define UNLOCK() LeaveCriticalSection(&GC_allocate_ml);
534 # ifndef SET_LOCK_HOLDER
535 # define SET_LOCK_HOLDER()
536 # define UNSET_LOCK_HOLDER()
537 # define I_HOLD_LOCK() FALSE
538 /* Used on platforms were locks can be reacquired, */
539 /* so it doesn't matter if we lie. */
545 # ifndef SET_LOCK_HOLDER
546 # define SET_LOCK_HOLDER()
547 # define UNSET_LOCK_HOLDER()
548 # define I_HOLD_LOCK() FALSE
549 /* Used on platforms were locks can be reacquired, */
550 /* so it doesn't matter if we lie. */
557 # ifndef DCL_LOCK_STATE
558 # define DCL_LOCK_STATE
561 # define FASTLOCK() LOCK()
562 # define FASTLOCK_SUCCEEDED() TRUE
563 # define FASTUNLOCK() UNLOCK()
566 /* Delay any interrupts or signals that may abort this thread. Data */
567 /* structures are in a consistent state outside this pair of calls. */
568 /* ANSI C allows both to be empty (though the standard isn't very */
569 /* clear on that point). Standard malloc implementations are usually */
570 /* neither interruptable nor thread-safe, and thus correspond to */
571 /* empty definitions. */
573 # define DISABLE_SIGNALS() \
574 PCR_Th_SetSigMask(PCR_allSigsBlocked,&GC_old_sig_mask)
575 # define ENABLE_SIGNALS() \
576 PCR_Th_SetSigMask(&GC_old_sig_mask, NIL)
578 # if defined(SRC_M3) || defined(AMIGA) || defined(SOLARIS_THREADS) \
579 || defined(MSWIN32) || defined(MACOS) || defined(DJGPP) \
580 || defined(NO_SIGNALS) || defined(IRIX_THREADS) \
581 || defined(IRIX_JDK_THREADS) || defined(LINUX_THREADS)
582 /* Also useful for debugging. */
583 /* Should probably use thr_sigsetmask for SOLARIS_THREADS. */
584 # define DISABLE_SIGNALS()
585 # define ENABLE_SIGNALS()
587 # define DISABLE_SIGNALS() GC_disable_signals()
588 void GC_disable_signals();
589 # define ENABLE_SIGNALS() GC_enable_signals()
590 void GC_enable_signals();
595 * Stop and restart mutator threads.
598 # include "th/PCR_ThCtl.h"
599 # define STOP_WORLD() \
600 PCR_ThCtl_SetExclusiveMode(PCR_ThCtl_ExclusiveMode_stopNormal, \
601 PCR_allSigsBlocked, \
603 # define START_WORLD() \
604 PCR_ThCtl_SetExclusiveMode(PCR_ThCtl_ExclusiveMode_null, \
605 PCR_allSigsBlocked, \
608 # if defined(SOLARIS_THREADS) || defined(WIN32_THREADS) \
609 || defined(IRIX_THREADS) || defined(LINUX_THREADS) \
610 || defined(IRIX_JDK_THREADS)
611 void GC_stop_world();
612 void GC_start_world();
613 # define STOP_WORLD() GC_stop_world()
614 # define START_WORLD() GC_start_world()
616 # define STOP_WORLD()
617 # define START_WORLD()
623 # define ABORT(s) PCR_Base_Panic(s)
626 # define ABORT(msg) abort();
628 GC_API void GC_abort();
629 # define ABORT(msg) GC_abort(msg);
633 /* Exit abnormally, but without making a mess (e.g. out of memory) */
635 # define EXIT() PCR_Base_Exit(1,PCR_waitForever)
637 # define EXIT() (void)exit(1)
640 /* Print warning message, e.g. almost out of memory. */
641 # define WARN(msg,arg) (*GC_current_warn_proc)(msg, (GC_word)(arg))
642 extern GC_warn_proc GC_current_warn_proc;
644 /*********************************/
646 /* Word-size-dependent defines */
648 /*********************************/
651 # define WORDS_TO_BYTES(x) ((x)<<2)
652 # define BYTES_TO_WORDS(x) ((x)>>2)
653 # define LOGWL ((word)5) /* log[2] of CPP_WORDSZ */
654 # define modWORDSZ(n) ((n) & 0x1f) /* n mod size of word */
661 # define WORDS_TO_BYTES(x) ((x)<<3)
662 # define BYTES_TO_WORDS(x) ((x)>>3)
663 # define LOGWL ((word)6) /* log[2] of CPP_WORDSZ */
664 # define modWORDSZ(n) ((n) & 0x3f) /* n mod size of word */
670 #define WORDSZ ((word)CPP_WORDSZ)
671 #define SIGNB ((word)1 << (WORDSZ-1))
672 #define BYTES_PER_WORD ((word)(sizeof (word)))
673 #define ONES ((word)(-1))
674 #define divWORDSZ(n) ((n) >> LOGWL) /* divide n by size of word */
676 /*********************/
678 /* Size Parameters */
680 /*********************/
682 /* heap block size, bytes. Should be power of 2 */
686 # define CPP_LOG_HBLKSIZE 10
688 # if CPP_WORDSZ == 32
689 # define CPP_LOG_HBLKSIZE 12
691 # define CPP_LOG_HBLKSIZE 13
696 # define CPP_LOG_HBLKSIZE 9
698 # if HBLKSIZE == 1024
699 # define CPP_LOG_HBLKSIZE 10
701 # if HBLKSIZE == 2048
702 # define CPP_LOG_HBLKSIZE 11
704 # if HBLKSIZE == 4096
705 # define CPP_LOG_HBLKSIZE 12
707 # if HBLKSIZE == 8192
708 # define CPP_LOG_HBLKSIZE 13
710 # if HBLKSIZE == 16384
711 # define CPP_LOG_HBLKSIZE 14
713 # ifndef CPP_LOG_HBLKSIZE
718 # define CPP_HBLKSIZE (1 << CPP_LOG_HBLKSIZE)
719 # define LOG_HBLKSIZE ((word)CPP_LOG_HBLKSIZE)
720 # define HBLKSIZE ((word)CPP_HBLKSIZE)
723 /* max size objects supported by freelist (larger objects may be */
724 /* allocated, but less efficiently) */
726 #define CPP_MAXOBJSZ BYTES_TO_WORDS(CPP_HBLKSIZE/2)
727 #define MAXOBJSZ ((word)CPP_MAXOBJSZ)
729 # define divHBLKSZ(n) ((n) >> LOG_HBLKSIZE)
731 # define HBLK_PTR_DIFF(p,q) divHBLKSZ((ptr_t)p - (ptr_t)q)
732 /* Equivalent to subtracting 2 hblk pointers. */
733 /* We do it this way because a compiler should */
734 /* find it hard to use an integer division */
735 /* instead of a shift. The bundled SunOS 4.1 */
736 /* o.w. sometimes pessimizes the subtraction to */
737 /* involve a call to .div. */
739 # define modHBLKSZ(n) ((n) & (HBLKSIZE-1))
741 # define HBLKPTR(objptr) ((struct hblk *)(((word) (objptr)) & ~(HBLKSIZE-1)))
743 # define HBLKDISPL(objptr) (((word) (objptr)) & (HBLKSIZE-1))
745 /* Round up byte allocation requests to integral number of words, etc. */
746 # ifdef ADD_BYTE_AT_END
747 # define ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + WORDS_TO_BYTES(1))
749 # define ALIGNED_WORDS(n) (BYTES_TO_WORDS((n) + WORDS_TO_BYTES(2)) & ~1)
751 # define ALIGNED_WORDS(n) ROUNDED_UP_WORDS(n)
753 # define SMALL_OBJ(bytes) ((bytes) < WORDS_TO_BYTES(MAXOBJSZ))
754 # define ADD_SLOP(bytes) ((bytes)+1)
756 # define ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + (WORDS_TO_BYTES(1) - 1))
758 # define ALIGNED_WORDS(n) \
759 (BYTES_TO_WORDS((n) + WORDS_TO_BYTES(2) - 1) & ~1)
761 # define ALIGNED_WORDS(n) ROUNDED_UP_WORDS(n)
763 # define SMALL_OBJ(bytes) ((bytes) <= WORDS_TO_BYTES(MAXOBJSZ))
764 # define ADD_SLOP(bytes) (bytes)
769 * Hash table representation of sets of pages. This assumes it is
770 * OK to add spurious entries to sets.
771 * Used by black-listing code, and perhaps by dirty bit maintenance code.
775 # define LOG_PHT_ENTRIES 17
777 # define LOG_PHT_ENTRIES 14 /* Collisions are likely if heap grows */
778 /* to more than 16K hblks = 64MB. */
779 /* Each hash table occupies 2K bytes. */
781 # define PHT_ENTRIES ((word)1 << LOG_PHT_ENTRIES)
782 # define PHT_SIZE (PHT_ENTRIES >> LOGWL)
783 typedef word page_hash_table[PHT_SIZE];
785 # define PHT_HASH(addr) ((((word)(addr)) >> LOG_HBLKSIZE) & (PHT_ENTRIES - 1))
787 # define get_pht_entry_from_index(bl, index) \
788 (((bl)[divWORDSZ(index)] >> modWORDSZ(index)) & 1)
789 # define set_pht_entry_from_index(bl, index) \
790 (bl)[divWORDSZ(index)] |= (word)1 << modWORDSZ(index)
791 # define clear_pht_entry_from_index(bl, index) \
792 (bl)[divWORDSZ(index)] &= ~((word)1 << modWORDSZ(index))
796 /********************************************/
798 /* H e a p B l o c k s */
800 /********************************************/
802 /* heap block header */
803 #define HBLKMASK (HBLKSIZE-1)
805 #define BITS_PER_HBLK (HBLKSIZE * 8)
807 #define MARK_BITS_PER_HBLK (BITS_PER_HBLK/CPP_WORDSZ)
809 /* We allocate 1 bit/word. Only the first word */
810 /* in each object is actually marked. */
813 # define MARK_BITS_SZ (((MARK_BITS_PER_HBLK + 2*CPP_WORDSZ - 1) \
816 # define MARK_BITS_SZ ((MARK_BITS_PER_HBLK + CPP_WORDSZ - 1)/CPP_WORDSZ)
818 /* Upper bound on number of mark words per heap block */
821 word hb_sz; /* If in use, size in words, of objects in the block. */
822 /* if free, the size in bytes of the whole block */
823 struct hblk * hb_next; /* Link field for hblk free list */
824 /* and for lists of chunks waiting to be */
826 struct hblk * hb_prev; /* Backwards link for free list. */
827 word hb_descr; /* object descriptor for marking. See */
829 char* hb_map; /* A pointer to a pointer validity map of the block. */
830 /* See GC_obj_map. */
831 /* Valid for all blocks with headers. */
832 /* Free blocks point to GC_invalid_map. */
833 unsigned char hb_obj_kind;
834 /* Kind of objects in the block. Each kind */
835 /* identifies a mark procedure and a set of */
836 /* list headers. Sometimes called regions. */
837 unsigned char hb_flags;
838 # define IGNORE_OFF_PAGE 1 /* Ignore pointers that do not */
839 /* point to the first page of */
841 # define WAS_UNMAPPED 2 /* This is a free block, which has */
842 /* been unmapped from the address */
844 /* GC_remap must be invoked on it */
845 /* before it can be reallocated. */
846 /* Only set with USE_MUNMAP. */
847 unsigned short hb_last_reclaimed;
848 /* Value of GC_gc_no when block was */
849 /* last allocated or swept. May wrap. */
850 /* For a free block, this is maintained */
851 /* unly for USE_MUNMAP, and indicates */
852 /* when the header was allocated, or */
853 /* when the size of the block last */
855 word hb_marks[MARK_BITS_SZ];
856 /* Bit i in the array refers to the */
857 /* object starting at the ith word (header */
858 /* INCLUDED) in the heap block. */
859 /* The lsb of word 0 is numbered 0. */
862 /* heap block body */
864 # define DISCARD_WORDS 0
865 /* Number of words to be dropped at the beginning of each block */
866 /* Must be a multiple of WORDSZ. May reasonably be nonzero */
867 /* on machines that don't guarantee longword alignment of */
868 /* pointers, so that the number of false hits is minimized. */
869 /* 0 and WORDSZ are probably the only reasonable values. */
871 # define BODY_SZ ((HBLKSIZE-WORDS_TO_BYTES(DISCARD_WORDS))/sizeof(word))
874 # if (DISCARD_WORDS != 0)
875 word garbage[DISCARD_WORDS];
877 word hb_body[BODY_SZ];
880 # define HDR_WORDS ((word)DISCARD_WORDS)
881 # define HDR_BYTES ((word)WORDS_TO_BYTES(DISCARD_WORDS))
883 # define OBJ_SZ_TO_BLOCKS(sz) \
884 divHBLKSZ(HDR_BYTES + WORDS_TO_BYTES(sz) + HBLKSIZE-1)
885 /* Size of block (in units of HBLKSIZE) needed to hold objects of */
886 /* given sz (in words). */
888 /* Object free list link */
889 # define obj_link(p) (*(ptr_t *)(p))
891 /* The type of mark procedures. This really belongs in gc_mark.h. */
892 /* But we put it here, so that we can avoid scanning the mark proc */
894 typedef struct ms_entry * (*mark_proc)(/* word * addr, mark_stack_ptr,
895 mark_stack_limit, env */);
896 # define LOG_MAX_MARK_PROCS 6
897 # define MAX_MARK_PROCS (1 << LOG_MAX_MARK_PROCS)
899 /* Root sets. Logically private to mark_rts.c. But we don't want the */
900 /* tables scanned, so we put them here. */
901 /* MAX_ROOT_SETS is the maximum number of ranges that can be */
902 /* registered as static roots. */
904 # define MAX_ROOT_SETS 4096
907 # define MAX_ROOT_SETS 1024
910 # define MAX_ROOT_SETS 512
911 /* Under NT, we add only written pages, which can result */
912 /* in many small root sets. */
914 # define MAX_ROOT_SETS 64
919 # define MAX_EXCLUSIONS (MAX_ROOT_SETS/4)
920 /* Maximum number of segments that can be excluded from root sets. */
923 * Data structure for excluded static roots.
930 /* Data structure for list of root sets. */
931 /* We keep a hash table, so that we can filter out duplicate additions. */
932 /* Under Win32, we need to do a better job of filtering overlaps, so */
933 /* we resort to sequential search, and pay the price. */
938 struct roots * r_next;
941 /* Delete before registering new dynamic libraries */
945 /* Size of hash table index to roots. */
946 # define LOG_RT_SIZE 6
947 # define RT_SIZE (1 << LOG_RT_SIZE) /* Power of 2, may be != MAX_ROOT_SETS */
950 /* Lists of all heap blocks and free lists */
951 /* as well as other random data structures */
952 /* that should not be scanned by the */
954 /* These are grouped together in a struct */
955 /* so that they can be easily skipped by the */
956 /* GC_mark routine. */
957 /* The ordering is weird to make GC_malloc */
958 /* faster by keeping the important fields */
959 /* sufficiently close together that a */
960 /* single load of a base register will do. */
961 /* Scalars that could easily appear to */
962 /* be pointers are also put here. */
963 /* The main fields should precede any */
964 /* conditionally included fields, so that */
965 /* gc_inl.h will work even if a different set */
966 /* of macros is defined when the client is */
972 ptr_t _last_heap_addr;
973 ptr_t _prev_heap_addr;
974 word _large_free_bytes;
975 /* Total bytes contained in blocks on large object free */
977 word _words_allocd_before_gc;
978 /* Number of words allocated before this */
979 /* collection cycle. */
981 /* Number of words allocated during this collection cycle */
983 /* Number of words wasted due to internal fragmentation */
984 /* in large objects, or due to dropping blacklisted */
985 /* blocks, since last gc. Approximate. */
986 word _words_finalized;
987 /* Approximate number of words in objects (and headers) */
988 /* That became ready for finalization in the last */
990 word _non_gc_bytes_at_gc;
991 /* Number of explicitly managed bytes of storage */
992 /* at last collection. */
994 /* Number of explicitly deallocated words of memory */
995 /* since last collection. */
996 mark_proc _mark_procs[MAX_MARK_PROCS];
997 /* Table of user-defined mark procedures. There is */
998 /* a small number of these, which can be referenced */
999 /* by DS_PROC mark descriptors. See gc_mark.h. */
1000 ptr_t _objfreelist[MAXOBJSZ+1];
1001 /* free list for objects */
1002 ptr_t _aobjfreelist[MAXOBJSZ+1];
1003 /* free list for atomic objs */
1005 ptr_t _uobjfreelist[MAXOBJSZ+1];
1006 /* uncollectable but traced objs */
1007 /* objects on this and auobjfreelist */
1008 /* are always marked, except during */
1009 /* garbage collections. */
1010 # ifdef ATOMIC_UNCOLLECTABLE
1011 ptr_t _auobjfreelist[MAXOBJSZ+1];
1013 /* uncollectable but traced objs */
1016 word _composite_in_use;
1017 /* Number of words in accessible composite */
1019 word _atomic_in_use;
1020 /* Number of words in accessible atomic */
1024 word _unmapped_bytes;
1027 unsigned _size_map[WORDS_TO_BYTES(MAXOBJSZ+1)];
1028 /* Number of words to allocate for a given allocation request in */
1032 # ifdef STUBBORN_ALLOC
1033 ptr_t _sobjfreelist[MAXOBJSZ+1];
1035 /* free list for immutable objects */
1036 ptr_t _obj_map[MAXOBJSZ+1];
1037 /* If not NIL, then a pointer to a map of valid */
1038 /* object addresses. _obj_map[sz][i] is j if the */
1039 /* address block_start+i is a valid pointer */
1040 /* to an object at */
1041 /* block_start+i&~3 - WORDS_TO_BYTES(j). */
1042 /* (If ALL_INTERIOR_POINTERS is defined, then */
1043 /* instead ((short *)(hb_map[sz])[i] is j if */
1044 /* block_start+WORDS_TO_BYTES(i) is in the */
1045 /* interior of an object starting at */
1046 /* block_start+WORDS_TO_BYTES(i-j)). */
1047 /* It is OBJ_INVALID if */
1048 /* block_start+WORDS_TO_BYTES(i) is not */
1049 /* valid as a pointer to an object. */
1050 /* We assume all values of j <= OBJ_INVALID. */
1051 /* The zeroth entry corresponds to large objects.*/
1052 # ifdef ALL_INTERIOR_POINTERS
1053 # define map_entry_type short
1054 # define OBJ_INVALID 0x7fff
1055 # define MAP_ENTRY(map, bytes) \
1056 (((map_entry_type *)(map))[BYTES_TO_WORDS(bytes)])
1057 # define MAP_ENTRIES BYTES_TO_WORDS(HBLKSIZE)
1058 # define MAP_SIZE (MAP_ENTRIES * sizeof(map_entry_type))
1059 # define OFFSET_VALID(displ) TRUE
1060 # define CPP_MAX_OFFSET (HBLKSIZE - HDR_BYTES - 1)
1061 # define MAX_OFFSET ((word)CPP_MAX_OFFSET)
1063 # define map_entry_type char
1064 # define OBJ_INVALID 0x7f
1065 # define MAP_ENTRY(map, bytes) \
1067 # define MAP_ENTRIES HBLKSIZE
1068 # define MAP_SIZE MAP_ENTRIES
1069 # define CPP_MAX_OFFSET (WORDS_TO_BYTES(OBJ_INVALID) - 1)
1070 # define MAX_OFFSET ((word)CPP_MAX_OFFSET)
1071 # define VALID_OFFSET_SZ \
1072 (CPP_MAX_OFFSET > WORDS_TO_BYTES(CPP_MAXOBJSZ)? \
1074 : WORDS_TO_BYTES(CPP_MAXOBJSZ)+1)
1075 char _valid_offsets[VALID_OFFSET_SZ];
1076 /* GC_valid_offsets[i] == TRUE ==> i */
1077 /* is registered as a displacement. */
1078 # define OFFSET_VALID(displ) GC_valid_offsets[displ]
1079 char _modws_valid_offsets[sizeof(word)];
1080 /* GC_valid_offsets[i] ==> */
1081 /* GC_modws_valid_offsets[i%sizeof(word)] */
1083 # ifdef STUBBORN_ALLOC
1084 page_hash_table _changed_pages;
1085 /* Stubborn object pages that were changes since last call to */
1086 /* GC_read_changed. */
1087 page_hash_table _prev_changed_pages;
1088 /* Stubborn object pages that were changes before last call to */
1089 /* GC_read_changed. */
1091 # if defined(PROC_VDB) || defined(MPROTECT_VDB)
1092 page_hash_table _grungy_pages; /* Pages that were dirty at last */
1093 /* GC_read_dirty. */
1095 # ifdef MPROTECT_VDB
1096 VOLATILE page_hash_table _dirty_pages;
1097 /* Pages dirtied since last GC_read_dirty. */
1100 page_hash_table _written_pages; /* Pages ever dirtied */
1102 # ifdef LARGE_CONFIG
1103 # if CPP_WORDSZ > 32
1104 # define MAX_HEAP_SECTS 4096 /* overflows at roughly 64 GB */
1106 # define MAX_HEAP_SECTS 768 /* Separately added heap sections. */
1109 # define MAX_HEAP_SECTS 256
1112 ptr_t hs_start; word hs_bytes;
1113 } _heap_sects[MAX_HEAP_SECTS];
1115 ptr_t _heap_bases[MAX_HEAP_SECTS];
1116 /* Start address of memory regions obtained from kernel. */
1118 struct roots _static_roots[MAX_ROOT_SETS];
1120 struct roots * _root_index[RT_SIZE];
1122 struct exclusion _excl_table[MAX_EXCLUSIONS];
1123 /* Block header index; see gc_headers.h */
1124 bottom_index * _all_nils;
1125 bottom_index * _top_index [TOP_SZ];
1126 #ifdef SAVE_CALL_CHAIN
1127 struct callinfo _last_stack[NFRAMES]; /* Stack at last garbage collection.*/
1128 /* Useful for debugging mysterious */
1129 /* object disappearances. */
1130 /* In the multithreaded case, we */
1131 /* currently only save the calling */
1136 GC_API GC_FAR struct _GC_arrays GC_arrays;
1138 # define GC_objfreelist GC_arrays._objfreelist
1139 # define GC_aobjfreelist GC_arrays._aobjfreelist
1140 # define GC_uobjfreelist GC_arrays._uobjfreelist
1141 # ifdef ATOMIC_UNCOLLECTABLE
1142 # define GC_auobjfreelist GC_arrays._auobjfreelist
1144 # define GC_sobjfreelist GC_arrays._sobjfreelist
1145 # define GC_valid_offsets GC_arrays._valid_offsets
1146 # define GC_modws_valid_offsets GC_arrays._modws_valid_offsets
1147 # ifdef STUBBORN_ALLOC
1148 # define GC_changed_pages GC_arrays._changed_pages
1149 # define GC_prev_changed_pages GC_arrays._prev_changed_pages
1151 # define GC_obj_map GC_arrays._obj_map
1152 # define GC_last_heap_addr GC_arrays._last_heap_addr
1153 # define GC_prev_heap_addr GC_arrays._prev_heap_addr
1154 # define GC_words_allocd GC_arrays._words_allocd
1155 # define GC_words_wasted GC_arrays._words_wasted
1156 # define GC_large_free_bytes GC_arrays._large_free_bytes
1157 # define GC_words_finalized GC_arrays._words_finalized
1158 # define GC_non_gc_bytes_at_gc GC_arrays._non_gc_bytes_at_gc
1159 # define GC_mem_freed GC_arrays._mem_freed
1160 # define GC_mark_procs GC_arrays._mark_procs
1161 # define GC_heapsize GC_arrays._heapsize
1162 # define GC_max_heapsize GC_arrays._max_heapsize
1163 # define GC_words_allocd_before_gc GC_arrays._words_allocd_before_gc
1164 # define GC_heap_sects GC_arrays._heap_sects
1165 # define GC_last_stack GC_arrays._last_stack
1167 # define GC_unmapped_bytes GC_arrays._unmapped_bytes
1170 # define GC_heap_bases GC_arrays._heap_bases
1172 # define GC_static_roots GC_arrays._static_roots
1173 # define GC_root_index GC_arrays._root_index
1174 # define GC_excl_table GC_arrays._excl_table
1175 # define GC_all_nils GC_arrays._all_nils
1176 # define GC_top_index GC_arrays._top_index
1177 # if defined(PROC_VDB) || defined(MPROTECT_VDB)
1178 # define GC_grungy_pages GC_arrays._grungy_pages
1180 # ifdef MPROTECT_VDB
1181 # define GC_dirty_pages GC_arrays._dirty_pages
1184 # define GC_written_pages GC_arrays._written_pages
1187 # define GC_composite_in_use GC_arrays._composite_in_use
1188 # define GC_atomic_in_use GC_arrays._atomic_in_use
1191 # define GC_size_map GC_arrays._size_map
1194 # define beginGC_arrays ((ptr_t)(&GC_arrays))
1195 # define endGC_arrays (((ptr_t)(&GC_arrays)) + (sizeof GC_arrays))
1198 # define MAXOBJKINDS 16
1200 extern struct obj_kind {
1201 ptr_t *ok_freelist; /* Array of free listheaders for this kind of object */
1202 /* Point either to GC_arrays or to storage allocated */
1203 /* with GC_scratch_alloc. */
1204 struct hblk **ok_reclaim_list;
1205 /* List headers for lists of blocks waiting to be */
1207 word ok_descriptor; /* Descriptor template for objects in this */
1209 GC_bool ok_relocate_descr;
1210 /* Add object size in bytes to descriptor */
1211 /* template to obtain descriptor. Otherwise */
1212 /* template is used as is. */
1213 GC_bool ok_init; /* Clear objects before putting them on the free list. */
1214 } GC_obj_kinds[MAXOBJKINDS];
1216 # define endGC_obj_kinds (((ptr_t)(&GC_obj_kinds)) + (sizeof GC_obj_kinds))
1218 # define end_gc_area ((ptr_t)endGC_arrays == (ptr_t)(&GC_obj_kinds) ? \
1219 endGC_obj_kinds : endGC_arrays)
1221 /* Predefined kinds: */
1224 # define UNCOLLECTABLE 2
1225 # ifdef ATOMIC_UNCOLLECTABLE
1226 # define AUNCOLLECTABLE 3
1228 # define IS_UNCOLLECTABLE(k) (((k) & ~1) == UNCOLLECTABLE)
1231 # define IS_UNCOLLECTABLE(k) ((k) == UNCOLLECTABLE)
1234 extern int GC_n_kinds;
1236 GC_API word GC_fo_entries;
1238 extern word GC_n_heap_sects; /* Number of separately added heap */
1241 extern word GC_page_size;
1244 extern word GC_n_heap_bases; /* See GC_heap_bases. */
1247 extern word GC_total_stack_black_listed;
1248 /* Number of bytes on stack blacklist. */
1250 extern word GC_black_list_spacing;
1251 /* Average number of bytes between blacklisted */
1252 /* blocks. Approximate. */
1253 /* Counts only blocks that are */
1254 /* "stack-blacklisted", i.e. that are */
1255 /* problematic in the interior of an object. */
1257 extern char * GC_invalid_map;
1258 /* Pointer to the nowhere valid hblk map */
1259 /* Blocks pointing to this map are free. */
1261 extern struct hblk * GC_hblkfreelist[];
1262 /* List of completely empty heap blocks */
1263 /* Linked through hb_next field of */
1264 /* header structure associated with */
1267 extern GC_bool GC_is_initialized; /* GC_init() has been run. */
1269 extern GC_bool GC_objects_are_marked; /* There are marked objects in */
1272 #ifndef SMALL_CONFIG
1273 extern GC_bool GC_incremental;
1274 /* Using incremental/generational collection. */
1276 # define GC_incremental TRUE
1277 /* Hopefully allow optimizer to remove some code. */
1280 extern GC_bool GC_dirty_maintained;
1281 /* Dirty bits are being maintained, */
1282 /* either for incremental collection, */
1283 /* or to limit the root set. */
1285 extern word GC_root_size; /* Total size of registered root sections */
1287 extern GC_bool GC_debugging_started; /* GC_debug_malloc has been called. */
1289 extern ptr_t GC_least_plausible_heap_addr;
1290 extern ptr_t GC_greatest_plausible_heap_addr;
1291 /* Bounds on the heap. Guaranteed valid */
1292 /* Likely to include future heap expansion. */
1296 # define abs(x) ((x) < 0? (-(x)) : (x))
1300 /* Marks are in a reserved area in */
1301 /* each heap block. Each word has one mark bit associated */
1302 /* with it. Only those corresponding to the beginning of an */
1303 /* object are used. */
1306 /* Mark bit operations */
1309 * Retrieve, set, clear the mark bit corresponding
1310 * to the nth word in a given heap block.
1312 * (Recall that bit n corresponds to object beginning at word n
1313 * relative to the beginning of the block, including unused words)
1316 # define mark_bit_from_hdr(hhdr,n) (((hhdr)->hb_marks[divWORDSZ(n)] \
1317 >> (modWORDSZ(n))) & (word)1)
1318 # define set_mark_bit_from_hdr(hhdr,n) (hhdr)->hb_marks[divWORDSZ(n)] \
1319 |= (word)1 << modWORDSZ(n)
1321 # define clear_mark_bit_from_hdr(hhdr,n) (hhdr)->hb_marks[divWORDSZ(n)] \
1322 &= ~((word)1 << modWORDSZ(n))
1324 /* Important internal collector routines */
1326 ptr_t GC_approx_sp();
1328 GC_bool GC_should_collect();
1329 #ifdef PRESERVE_LAST
1330 GC_bool GC_in_last_heap_sect(/* ptr_t */);
1331 /* In last added heap section? If so, avoid breaking up. */
1333 void GC_apply_to_all_blocks(/*fn, client_data*/);
1334 /* Invoke fn(hbp, client_data) for each */
1335 /* allocated heap block. */
1336 struct hblk * GC_next_used_block(/* struct hblk * h */);
1337 /* Return first in-use block >= h */
1338 struct hblk * GC_prev_block(/* struct hblk * h */);
1339 /* Return last block <= h. Returned block */
1340 /* is managed by GC, but may or may not be in */
1342 void GC_mark_init();
1343 void GC_clear_marks(); /* Clear mark bits for all heap objects. */
1344 void GC_invalidate_mark_state(); /* Tell the marker that marked */
1345 /* objects may point to unmarked */
1346 /* ones, and roots may point to */
1347 /* unmarked objects. */
1348 /* Reset mark stack. */
1349 void GC_mark_from_mark_stack(); /* Mark from everything on the mark stack. */
1350 /* Return after about one pages worth of */
1352 GC_bool GC_mark_stack_empty();
1353 GC_bool GC_mark_some(/* cold_gc_frame */);
1354 /* Perform about one pages worth of marking */
1355 /* work of whatever kind is needed. Returns */
1356 /* quickly if no collection is in progress. */
1357 /* Return TRUE if mark phase finished. */
1358 void GC_initiate_gc(); /* initiate collection. */
1359 /* If the mark state is invalid, this */
1360 /* becomes full colleection. Otherwise */
1362 void GC_push_all(/*b,t*/); /* Push everything in a range */
1363 /* onto mark stack. */
1364 void GC_push_dirty(/*b,t*/); /* Push all possibly changed */
1365 /* subintervals of [b,t) onto */
1367 #ifndef SMALL_CONFIG
1368 void GC_push_conditional(/* ptr_t b, ptr_t t, GC_bool all*/);
1370 # define GC_push_conditional(b, t, all) GC_push_all(b, t)
1372 /* Do either of the above, depending */
1373 /* on the third arg. */
1374 void GC_push_all_stack(/*b,t*/); /* As above, but consider */
1375 /* interior pointers as valid */
1376 void GC_push_all_eager(/*b,t*/); /* Same as GC_push_all_stack, but */
1377 /* ensures that stack is scanned */
1378 /* immediately, not just scheduled */
1381 void GC_push_all_stack_partially_eager(/* bottom, top, cold_gc_frame */);
1382 /* Similar to GC_push_all_eager, but only the */
1383 /* part hotter than cold_gc_frame is scanned */
1384 /* immediately. Needed to endure that callee- */
1385 /* save registers are not missed. */
1387 /* In the threads case, we push part of the current thread stack */
1388 /* with GC_push_all_eager when we push the registers. This gets the */
1389 /* callee-save registers that may disappear. The remainder of the */
1390 /* stacks are scheduled for scanning in *GC_push_other_roots, which */
1391 /* is thread-package-specific. */
1393 void GC_push_current_stack(/* ptr_t cold_gc_frame */);
1394 /* Push enough of the current stack eagerly to */
1395 /* ensure that callee-save registers saved in */
1396 /* GC frames are scanned. */
1397 /* In the non-threads case, schedule entire */
1398 /* stack for scanning. */
1399 void GC_push_roots(/* GC_bool all, ptr_t cold_gc_frame */);
1400 /* Push all or dirty roots. */
1401 extern void (*GC_push_other_roots)();
1402 /* Push system or application specific roots */
1403 /* onto the mark stack. In some environments */
1404 /* (e.g. threads environments) this is */
1405 /* predfined to be non-zero. A client supplied */
1406 /* replacement should also call the original */
1408 extern void (*GC_start_call_back)(/* void */);
1409 /* Called at start of full collections. */
1410 /* Not called if 0. Called with allocation */
1413 void GC_push_regs(); /* Push register contents onto mark stack. */
1414 void GC_remark(); /* Mark from all marked objects. Used */
1415 /* only if we had to drop something. */
1416 # if defined(MSWIN32)
1417 void __cdecl GC_push_one();
1419 void GC_push_one(/*p*/); /* If p points to an object, mark it */
1420 /* and push contents on the mark stack */
1422 void GC_push_one_checked(/*p*/); /* Ditto, omits plausibility test */
1423 void GC_push_marked(/* struct hblk h, hdr * hhdr */);
1424 /* Push contents of all marked objects in h onto */
1427 # define GC_push_next_marked_dirty(h) GC_push_next_marked(h)
1429 struct hblk * GC_push_next_marked_dirty(/* h */);
1430 /* Invoke GC_push_marked on next dirty block above h. */
1431 /* Return a pointer just past the end of this block. */
1432 #endif /* !SMALL_CONFIG */
1433 struct hblk * GC_push_next_marked(/* h */);
1434 /* Ditto, but also mark from clean pages. */
1435 struct hblk * GC_push_next_marked_uncollectable(/* h */);
1436 /* Ditto, but mark only from uncollectable pages. */
1437 GC_bool GC_stopped_mark(); /* Stop world and mark from all roots */
1439 void GC_clear_hdr_marks(/* hhdr */); /* Clear the mark bits in a header */
1440 void GC_set_hdr_marks(/* hhdr */); /* Set the mark bits in a header */
1441 void GC_add_roots_inner();
1442 GC_bool GC_is_static_root(/* ptr_t p */);
1443 /* Is the address p in one of the registered static */
1444 /* root sections? */
1445 void GC_register_dynamic_libraries();
1446 /* Add dynamic library data sections to the root set. */
1448 /* Machine dependent startup routines */
1449 ptr_t GC_get_stack_base();
1450 void GC_register_data_segments();
1452 /* Black listing: */
1454 # ifndef ALL_INTERIOR_POINTERS
1455 void GC_add_to_black_list_normal(/* bits, maybe source */);
1456 /* Register bits as a possible future false */
1457 /* reference from the heap or static data */
1458 # ifdef PRINT_BLACK_LIST
1459 # define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \
1460 GC_add_to_black_list_normal(bits, source)
1462 # define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \
1463 GC_add_to_black_list_normal(bits)
1466 # ifdef PRINT_BLACK_LIST
1467 # define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \
1468 GC_add_to_black_list_stack(bits, source)
1470 # define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \
1471 GC_add_to_black_list_stack(bits)
1475 void GC_add_to_black_list_stack(/* bits, maybe source */);
1476 struct hblk * GC_is_black_listed(/* h, len */);
1477 /* If there are likely to be false references */
1478 /* to a block starting at h of the indicated */
1479 /* length, then return the next plausible */
1480 /* starting location for h that might avoid */
1481 /* these false references. */
1482 void GC_promote_black_lists();
1483 /* Declare an end to a black listing phase. */
1484 void GC_unpromote_black_lists();
1485 /* Approximately undo the effect of the above. */
1486 /* This actually loses some information, but */
1487 /* only in a reasonably safe way. */
1488 word GC_number_stack_black_listed(/*struct hblk *start, struct hblk *endp1 */);
1489 /* Return the number of (stack) blacklisted */
1490 /* blocks in the range for statistical */
1493 ptr_t GC_scratch_alloc(/*bytes*/);
1494 /* GC internal memory allocation for */
1495 /* small objects. Deallocation is not */
1498 /* Heap block layout maps: */
1499 void GC_invalidate_map(/* hdr */);
1500 /* Remove the object map associated */
1501 /* with the block. This identifies */
1502 /* the block as invalid to the mark */
1504 GC_bool GC_add_map_entry(/*sz*/);
1505 /* Add a heap block map for objects of */
1506 /* size sz to obj_map. */
1507 /* Return FALSE on failure. */
1508 void GC_register_displacement_inner(/*offset*/);
1509 /* Version of GC_register_displacement */
1510 /* that assumes lock is already held */
1511 /* and signals are already disabled. */
1513 /* hblk allocation: */
1514 void GC_new_hblk(/*size_in_words, kind*/);
1515 /* Allocate a new heap block, and build */
1516 /* a free list in it. */
1517 struct hblk * GC_allochblk(/*size_in_words, kind*/);
1518 /* Allocate a heap block, clear it if */
1519 /* for composite objects, inform */
1520 /* the marker that block is valid */
1521 /* for objects of indicated size. */
1522 /* sz < 0 ==> atomic. */
1523 void GC_freehblk(); /* Deallocate a heap block and mark it */
1527 void GC_init_inner();
1528 GC_bool GC_expand_hp_inner();
1529 void GC_start_reclaim(/*abort_if_found*/);
1530 /* Restore unmarked objects to free */
1531 /* lists, or (if abort_if_found is */
1532 /* TRUE) report them. */
1533 /* Sweeping of small object pages is */
1534 /* largely deferred. */
1535 void GC_continue_reclaim(/*size, kind*/);
1536 /* Sweep pages of the given size and */
1537 /* kind, as long as possible, and */
1538 /* as long as the corr. free list is */
1540 void GC_reclaim_or_delete_all();
1541 /* Arrange for all reclaim lists to be */
1542 /* empty. Judiciously choose between */
1543 /* sweeping and discarding each page. */
1544 GC_bool GC_reclaim_all(/* GC_stop_func f*/);
1545 /* Reclaim all blocks. Abort (in a */
1546 /* consistent state) if f returns TRUE. */
1547 GC_bool GC_block_empty(/* hhdr */); /* Block completely unmarked? */
1548 GC_bool GC_never_stop_func(); /* Returns FALSE. */
1549 GC_bool GC_try_to_collect_inner(/* GC_stop_func f */);
1550 /* Collect; caller must have acquired */
1551 /* lock and disabled signals. */
1552 /* Collection is aborted if f returns */
1553 /* TRUE. Returns TRUE if it completes */
1555 # define GC_gcollect_inner() \
1556 (void) GC_try_to_collect_inner(GC_never_stop_func)
1557 void GC_finish_collection(); /* Finish collection. Mark bits are */
1558 /* consistent and lock is still held. */
1559 GC_bool GC_collect_or_expand(/* needed_blocks */);
1560 /* Collect or expand heap in an attempt */
1561 /* make the indicated number of free */
1562 /* blocks available. Should be called */
1563 /* until the blocks are available or */
1564 /* until it fails by returning FALSE. */
1565 GC_API void GC_init(); /* Initialize collector. */
1566 void GC_collect_a_little_inner(/* int n */);
1567 /* Do n units worth of garbage */
1568 /* collection work, if appropriate. */
1569 /* A unit is an amount appropriate for */
1570 /* HBLKSIZE bytes of allocation. */
1571 ptr_t GC_generic_malloc(/* bytes, kind */);
1572 /* Allocate an object of the given */
1573 /* kind. By default, there are only */
1574 /* a few kinds: composite(pointerfree), */
1575 /* atomic, uncollectable, etc. */
1576 /* We claim it's possible for clever */
1577 /* client code that understands GC */
1578 /* internals to add more, e.g. to */
1579 /* communicate object layout info */
1580 /* to the collector. */
1581 ptr_t GC_generic_malloc_ignore_off_page(/* bytes, kind */);
1582 /* As above, but pointers past the */
1583 /* first page of the resulting object */
1585 ptr_t GC_generic_malloc_inner(/* bytes, kind */);
1586 /* Ditto, but I already hold lock, etc. */
1587 ptr_t GC_generic_malloc_words_small GC_PROTO((size_t words, int kind));
1588 /* As above, but size in units of words */
1589 /* Bypasses MERGE_SIZES. Assumes */
1590 /* words <= MAXOBJSZ. */
1591 ptr_t GC_generic_malloc_inner_ignore_off_page(/* bytes, kind */);
1592 /* Allocate an object, where */
1593 /* the client guarantees that there */
1594 /* will always be a pointer to the */
1595 /* beginning of the object while the */
1596 /* object is live. */
1597 ptr_t GC_allocobj(/* sz_inn_words, kind */);
1598 /* Make the indicated */
1599 /* free list nonempty, and return its */
1602 void GC_init_headers();
1603 GC_bool GC_install_header(/*h*/);
1604 /* Install a header for block h. */
1605 /* Return FALSE on failure. */
1606 GC_bool GC_install_counts(/*h, sz*/);
1607 /* Set up forwarding counts for block */
1609 /* Return FALSE on failure. */
1610 void GC_remove_header(/*h*/);
1611 /* Remove the header for block h. */
1612 void GC_remove_counts(/*h, sz*/);
1613 /* Remove forwarding counts for h. */
1614 hdr * GC_find_header(/*p*/); /* Debugging only. */
1616 void GC_finalize(); /* Perform all indicated finalization actions */
1617 /* on unmarked objects. */
1618 /* Unreachable finalizable objects are enqueued */
1619 /* for processing by GC_invoke_finalizers. */
1620 /* Invoked with lock. */
1622 void GC_add_to_heap(/*p, bytes*/);
1623 /* Add a HBLKSIZE aligned chunk to the heap. */
1625 void GC_print_obj(/* ptr_t p */);
1626 /* P points to somewhere inside an object with */
1627 /* debugging info. Print a human readable */
1628 /* description of the object to stderr. */
1629 extern void (*GC_check_heap)();
1630 /* Check that all objects in the heap with */
1631 /* debugging info are intact. Print */
1632 /* descriptions of any that are not. */
1633 extern void (*GC_print_heap_obj)(/* ptr_t p */);
1634 /* If possible print s followed by a more */
1635 /* detailed description of the object */
1636 /* referred to by p. */
1638 /* Memory unmapping: */
1640 void GC_unmap_old(void);
1641 void GC_merge_unmapped(void);
1642 void GC_unmap(ptr_t start, word bytes);
1643 void GC_remap(ptr_t start, word bytes);
1644 void GC_unmap_gap(ptr_t start1, word bytes1, ptr_t start2, word bytes2);
1647 /* Virtual dirty bit implementation: */
1648 /* Each implementation exports the following: */
1649 void GC_read_dirty(); /* Retrieve dirty bits. */
1650 GC_bool GC_page_was_dirty(/* struct hblk * h */);
1651 /* Read retrieved dirty bits. */
1652 GC_bool GC_page_was_ever_dirty(/* struct hblk * h */);
1653 /* Could the page contain valid heap pointers? */
1654 void GC_is_fresh(/* struct hblk * h, word number_of_blocks */);
1655 /* Assert the region currently contains no */
1656 /* valid pointers. */
1657 void GC_write_hint(/* struct hblk * h */);
1658 /* h is about to be written. */
1659 void GC_dirty_init();
1661 /* Slow/general mark bit manipulation: */
1662 GC_API GC_bool GC_is_marked();
1663 void GC_clear_mark_bit();
1664 void GC_set_mark_bit();
1666 /* Stubborn objects: */
1667 void GC_read_changed(); /* Analogous to GC_read_dirty */
1668 GC_bool GC_page_was_changed(/* h */); /* Analogous to GC_page_was_dirty */
1669 void GC_clean_changing_list(); /* Collect obsolete changing list entries */
1670 void GC_stubborn_init();
1672 /* Debugging print routines: */
1673 void GC_print_block_list();
1674 void GC_print_hblkfreelist();
1675 void GC_print_heap_sects();
1676 void GC_print_static_roots();
1679 #ifdef KEEP_BACK_PTRS
1680 void GC_store_back_pointer(ptr_t source, ptr_t dest);
1681 void GC_marked_for_finalization(ptr_t dest);
1682 # define GC_STORE_BACK_PTR(source, dest) GC_store_back_pointer(source, dest)
1683 # define GC_MARKED_FOR_FINALIZATION(dest) GC_marked_for_finalization(dest)
1685 # define GC_STORE_BACK_PTR(source, dest)
1686 # define GC_MARKED_FOR_FINALIZATION(dest)
1689 /* Make arguments appear live to compiler */
1691 void GC_noop(void*, ...);
1693 GC_API void GC_noop();
1696 void GC_noop1(/* word arg */);
1698 /* Logging and diagnostic output: */
1699 GC_API void GC_printf GC_PROTO((char * format, long, long, long, long, long, long));
1700 /* A version of printf that doesn't allocate, */
1701 /* is restricted to long arguments, and */
1702 /* (unfortunately) doesn't use varargs for */
1703 /* portability. Restricted to 6 args and */
1704 /* 1K total output length. */
1705 /* (We use sprintf. Hopefully that doesn't */
1706 /* allocate for long arguments.) */
1707 # define GC_printf0(f) GC_printf(f, 0l, 0l, 0l, 0l, 0l, 0l)
1708 # define GC_printf1(f,a) GC_printf(f, (long)a, 0l, 0l, 0l, 0l, 0l)
1709 # define GC_printf2(f,a,b) GC_printf(f, (long)a, (long)b, 0l, 0l, 0l, 0l)
1710 # define GC_printf3(f,a,b,c) GC_printf(f, (long)a, (long)b, (long)c, 0l, 0l, 0l)
1711 # define GC_printf4(f,a,b,c,d) GC_printf(f, (long)a, (long)b, (long)c, \
1713 # define GC_printf5(f,a,b,c,d,e) GC_printf(f, (long)a, (long)b, (long)c, \
1714 (long)d, (long)e, 0l)
1715 # define GC_printf6(f,a,b,c,d,e,g) GC_printf(f, (long)a, (long)b, (long)c, \
1716 (long)d, (long)e, (long)g)
1718 void GC_err_printf(/* format, a, b, c, d, e, f */);
1719 # define GC_err_printf0(f) GC_err_puts(f)
1720 # define GC_err_printf1(f,a) GC_err_printf(f, (long)a, 0l, 0l, 0l, 0l, 0l)
1721 # define GC_err_printf2(f,a,b) GC_err_printf(f, (long)a, (long)b, 0l, 0l, 0l, 0l)
1722 # define GC_err_printf3(f,a,b,c) GC_err_printf(f, (long)a, (long)b, (long)c, \
1724 # define GC_err_printf4(f,a,b,c,d) GC_err_printf(f, (long)a, (long)b, \
1725 (long)c, (long)d, 0l, 0l)
1726 # define GC_err_printf5(f,a,b,c,d,e) GC_err_printf(f, (long)a, (long)b, \
1729 # define GC_err_printf6(f,a,b,c,d,e,g) GC_err_printf(f, (long)a, (long)b, \
1732 /* Ditto, writes to stderr. */
1734 void GC_err_puts(/* char *s */);
1735 /* Write s to stderr, don't buffer, don't add */
1736 /* newlines, don't ... */
1739 # ifdef GC_ASSERTIONS
1740 # define GC_ASSERT(expr) if(!(expr)) {\
1741 GC_err_printf2("Assertion failure: %s:%ld\n", \
1742 __FILE__, (unsigned long)__LINE__); \
1743 ABORT("assertion failure"); }
1745 # define GC_ASSERT(expr)
1748 # endif /* GC_PRIVATE_H */