/* * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers * Copyright (c) 1991-1993 by Xerox Corporation. All rights reserved. * * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED * OR IMPLIED. ANY USE IS AT YOUR OWN RISK. * * Permission is hereby granted to copy this garbage collector for any purpose, * provided the above notices are retained on all copies. */ # ifndef GC_PRIVATE_H # define GC_PRIVATE_H # ifndef GC_H # include "gc.h" # endif typedef GC_word word; typedef GC_signed_word signed_word; # ifndef CONFIG_H # include "config.h" # endif # ifndef HEADERS_H # include "gc_headers.h" # endif # ifndef bool typedef int bool; # endif # define TRUE 1 # define FALSE 0 typedef char * ptr_t; /* A generic pointer to which we can add */ /* byte displacments. */ #ifdef __STDC__ # if !(defined( sony_news ) ) # include # endif typedef void * extern_ptr_t; # define VOLATILE volatile #else typedef char * extern_ptr_t; # define VOLATILE #endif # ifndef OS2 # include # endif /*********************************/ /* */ /* Definitions for conservative */ /* collector */ /* */ /*********************************/ /*********************************/ /* */ /* Easily changeable parameters */ /* */ /*********************************/ #define STUBBORN_ALLOC /* Define stubborn allocation primitives */ #define ALL_INTERIOR_POINTERS /* Forces all pointers into the interior of an */ /* object to be considered valid. Also causes the */ /* sizes of all objects to be inflated by at least */ /* one byte. This should suffice to guarantee */ /* that in the presence of a compiler that does */ /* not perform garbage-collector-unsafe */ /* optimizations, all portable, strictly ANSI */ /* conforming C programs should be safely usable */ /* with malloc replaced by GC_malloc and free */ /* calls removed. There are several disadvantages: */ /* 1. There are probably no interesting, portable, */ /* strictly ANSI conforming C programs. */ /* 2. This option makes it hard for the collector */ /* to allocate space that is not ``pointed to'' */ /* by integers, etc. Under SunOS 4.X with a */ /* statically linked libc, we empiricaly */ /* observed that it would be difficult to */ /* allocate individual objects larger than 100K. */ /* Even if only smaller objects are allocated, */ /* more swap space is likely to be needed. */ /* Fortunately, much of this will never be */ /* touched. */ /* If you can easily avoid using this option, do. */ /* If not, try to keep individual objects small. */ #undef ALL_INTERIOR_POINTERS #define PRINTSTATS /* Print garbage collection statistics */ /* For less verbose output, undefine in reclaim.c */ #define PRINTTIMES /* Print the amount of time consumed by each garbage */ /* collection. */ #define PRINTBLOCKS /* Print object sizes associated with heap blocks, */ /* whether the objects are atomic or composite, and */ /* whether or not the block was found to be empty */ /* duing the reclaim phase. Typically generates */ /* about one screenful per garbage collection. */ #undef PRINTBLOCKS #define PRINTBLACKLIST /* Print black listed blocks, i.e. values that */ /* cause the allocator to avoid allocating certain */ /* blocks in order to avoid introducing "false */ /* hits". */ #undef PRINTBLACKLIST #ifdef SILENT # ifdef PRINTSTATS # undef PRINTSTATS # endif # ifdef PRINTTIMES # undef PRINTTIMES # endif # ifdef PRINTNBLOCKS # undef PRINTNBLOCKS # endif #endif #if defined(PRINTSTATS) && !defined(GATHERSTATS) # define GATHERSTATS #endif #ifdef SPARC # define ALIGN_DOUBLE /* Align objects of size > 1 word on 2 word */ /* boundaries. Wasteful of memory, but */ /* apparently required by SPARC architecture. */ #endif #if defined(SPARC) || defined(M68K) && defined(SUNOS) # if !defined(PCR) # define DYNAMIC_LOADING /* Search dynamic libraries for roots. */ # else /* PCR handles any dynamic loading whether with dlopen or otherwise */ # endif #endif #define MERGE_SIZES /* Round up some object sizes, so that fewer distinct */ /* free lists are actually maintained. This applies */ /* only to the top level routines in misc.c, not to */ /* user generated code that calls GC_allocobj and */ /* GC_allocaobj directly. */ /* Slows down average programs slightly. May however */ /* substantially reduce fragmentation if allocation */ /* request sizes are widely scattered. */ /* May save significant amounts of space for obj_map */ /* entries. */ /* ALIGN_DOUBLE requires MERGE_SIZES at present. */ # if defined(ALIGN_DOUBLE) && !defined(MERGE_SIZES) # define MERGE_SIZES # endif # define HINCR 16 /* Initial heap increment, in blocks of 4K */ # define MAXHINCR 512 /* Maximum heap increment, in blocks */ # define HINCR_MULT 5 /* After each new allocation, GC_hincr is */ # define HINCR_DIV 4 /* multiplied by HINCR_MULT/HINCR_DIV */ # define GC_MULT 3 /* Don't collect if the fraction of */ /* non-collectable memory in the heap */ /* exceeds GC_MUL/GC_DIV */ # define GC_DIV 4 # define NON_GC_HINCR ((word)8) /* Heap increment if most of heap if collection */ /* was suppressed because most of heap is not */ /* collectable */ /*********************************/ /* */ /* OS interface routines */ /* */ /*********************************/ #include #if !defined(__STDC__) && defined(SPARC) && defined(SUNOS4) clock_t clock(); /* Not in time.h, where it belongs */ #endif #if !defined(CLOCKS_PER_SEC) # define CLOCKS_PER_SEC 1000000 /* * This is technically a bug in the implementation. ANSI requires that * CLOCKS_PER_SEC be defined. But at least under SunOS4.1.1, it isn't. * Also note that the combination of ANSI C and POSIX is incredibly gross * here. The type clock_t is used by both clock() and times(). But on * some machines thes use different notions of a clock tick, CLOCKS_PER_SEC * seems to apply only to clock. Hence we use it here. On many machines, * including SunOS, clock actually uses units of microseconds (which are * not really clock ticks). */ #endif #define CLOCK_TYPE clock_t #define GET_TIME(x) x = clock() #define MS_TIME_DIFF(a,b) ((unsigned long) \ (1000.0*(double)((a)-(b))/(double)CLOCKS_PER_SEC)) /* We use bzero and bcopy internally. They may not be available. */ # if defined(SPARC) && defined(SUNOS4) # define BCOPY_EXISTS # endif # if defined(M68K) && defined(SUNOS) # define BCOPY_EXISTS # endif # if defined(VAX) # define BCOPY_EXISTS # endif # ifndef BCOPY_EXISTS # include # define bcopy(x,y,n) memcpy(y,x,n) # define bzero(x,n) memset(x, 0, n) # endif /* HBLKSIZE aligned allocation. 0 is taken to mean failure */ /* space is assumed to be cleared. */ # ifdef PCR char * real_malloc(); # define GET_MEM(bytes) HBLKPTR(real_malloc((size_t)bytes + HBLKSIZE) \ + HBLKSIZE-1) # define THREADS # else # ifdef OS2 void * os2_alloc(size_t bytes); # define GET_MEM(bytes) HBLKPTR((ptr_t)os2_alloc((size_t)bytes + HBLKSIZE) \ + HBLKSIZE-1) # else extern ptr_t GC_unix_get_mem(); # define GET_MEM(bytes) (struct hblk *)GC_unix_get_mem(bytes) # endif # endif /* * Mutual exclusion between allocator/collector routines. * Needed if there is more than one allocator thread. * FASTLOCK() is assumed to try to acquire the lock in a cheap and * dirty way that is acceptable for a few instructions, e.g. by * inhibiting preemption. This is assumed to have succeeded only * if a subsequent call to FASTLOCK_SUCCEEDED() returns TRUE. * FASTUNLOCK() is called whether or not FASTLOCK_SUCCEEDED(). * If signals cannot be tolerated with the FASTLOCK held, then * FASTLOCK should disable signals. The code executed under * FASTLOCK is otherwise immune to interruption, provided it is * not restarted. * DCL_LOCK_STATE declares any local variables needed by LOCK and UNLOCK * and/or DISABLE_SIGNALS and ENABLE_SIGNALS and/or FASTLOCK. * (There is currently no equivalent for FASTLOCK.) */ # ifdef PCR # include "th/PCR_Th.h" # include "th/PCR_ThCrSec.h" extern struct PCR_Th_MLRep GC_allocate_ml; # define DCL_LOCK_STATE PCR_sigset_t GC_old_sig_mask # define LOCK() PCR_Th_ML_Acquire(&GC_allocate_ml) # define UNLOCK() PCR_Th_ML_Release(&GC_allocate_ml) # define FASTLOCK() PCR_ThCrSec_EnterSys() /* Here we cheat (a lot): */ # define FASTLOCK_SUCCEEDED() (*(int *)(&GC_allocate_ml) == 0) /* TRUE if nobody currently holds the lock */ # define FASTUNLOCK() PCR_ThCrSec_ExitSys() # else # define DCL_LOCK_STATE # define LOCK() # define UNLOCK() # define FASTLOCK() LOCK() # define FASTLOCK_SUCCEEDED() TRUE # define FASTUNLOCK() UNLOCK() # endif /* Delay any interrupts or signals that may abort this thread. Data */ /* structures are in a consistent state outside this pair of calls. */ /* ANSI C allows both to be empty (though the standard isn't very */ /* clear on that point). Standard malloc implementations are usually */ /* neither interruptable nor thread-safe, and thus correspond to */ /* empty definitions. */ # ifdef PCR # define DISABLE_SIGNALS() \ PCR_Th_SetSigMask(PCR_allSigsBlocked,&GC_old_sig_mask) # define ENABLE_SIGNALS() \ PCR_Th_SetSigMask(&GC_old_sig_mask, NIL) # else # if 0 /* Useful for debugging, and unusually */ /* correct client code. */ # define DISABLE_SIGNALS() # define ENABLE_SIGNALS() # else # define DISABLE_SIGNALS() GC_disable_signals() void GC_disable_signals(); # define ENABLE_SIGNALS() GC_enable_signals() void GC_enable_signals(); # endif # endif /* * Stop and restart mutator threads. */ # ifdef PCR # include "th/PCR_ThCtl.h" # define STOP_WORLD() \ PCR_ThCtl_SetExclusiveMode(PCR_ThCtl_ExclusiveMode_stopNormal, \ PCR_allSigsBlocked, \ PCR_waitForever) # define START_WORLD() \ PCR_ThCtl_SetExclusiveMode(PCR_ThCtl_ExclusiveMode_null, \ PCR_allSigsBlocked, \ PCR_waitForever); # else # define STOP_WORLD() # define START_WORLD() # endif /* Abandon ship */ # ifdef PCR void PCR_Base_Panic(const char *fmt, ...); # define ABORT(s) PCR_Base_Panic(s) # else # define ABORT(s) abort(s) # endif /* Exit abnormally, but without making a mess (e.g. out of memory) */ # ifdef PCR void PCR_Base_Exit(int status); # define EXIT() PCR_Base_Exit(1) # else # define EXIT() (void)exit(1) # endif /* Print warning message, e.g. almost out of memory. */ # define WARN(s) GC_printf0(s) /*********************************/ /* */ /* Word-size-dependent defines */ /* */ /*********************************/ #if CPP_WORDSZ == 32 # define WORDS_TO_BYTES(x) ((x)<<2) # define BYTES_TO_WORDS(x) ((x)>>2) # define LOGWL ((word)5) /* log[2] of CPP_WORDSZ */ # define modWORDSZ(n) ((n) & 0x1f) /* n mod size of word */ #endif #if CPP_WORDSZ == 64 # define WORDS_TO_BYTES(x) ((x)<<3) # define BYTES_TO_WORDS(x) ((x)>>3) # define LOGWL ((word)6) /* log[2] of CPP_WORDSZ */ # define modWORDSZ(n) ((n) & 0x3f) /* n mod size of word */ #endif #define WORDSZ ((word)CPP_WORDSZ) #define SIGNB ((word)1 << (WORDSZ-1)) #define BYTES_PER_WORD ((word)(sizeof (word))) #define ONES ((word)(-1)) #define divWORDSZ(n) ((n) >> LOGWL) /* divide n by size of word */ /*********************/ /* */ /* Size Parameters */ /* */ /*********************/ /* heap block size, bytes. Should be power of 2 */ #if CPP_WORDSZ == 32 # define CPP_LOG_HBLKSIZE 12 #else # define CPP_LOG_HBLKSIZE 13 #endif #define LOG_HBLKSIZE ((word)CPP_LOG_HBLKSIZE) #define CPP_HBLKSIZE (1 << CPP_LOG_HBLKSIZE) #define HBLKSIZE ((word)CPP_HBLKSIZE) /* max size objects supported by freelist (larger objects may be */ /* allocated, but less efficiently) */ #define CPP_MAXOBJSZ BYTES_TO_WORDS(CPP_HBLKSIZE/2) #define MAXOBJSZ ((word)CPP_MAXOBJSZ) # define divHBLKSZ(n) ((n) >> LOG_HBLKSIZE) # define HBLK_PTR_DIFF(p,q) divHBLKSZ((ptr_t)p - (ptr_t)q) /* Equivalent to subtracting 2 hblk pointers. */ /* We do it this way because a compiler should */ /* find it hard to use an integer division */ /* instead of a shift. The bundled SunOS 4.1 */ /* o.w. sometimes pessimizes the subtraction to */ /* involve a call to .div. */ # define modHBLKSZ(n) ((n) & (HBLKSIZE-1)) # define HBLKPTR(objptr) ((struct hblk *)(((word) (objptr)) & ~(HBLKSIZE-1))) # define HBLKDISPL(objptr) (((word) (objptr)) & (HBLKSIZE-1)) /* Round up byte allocation requests to integral number of words: */ # ifdef ALL_INTERIOR_POINTERS # define ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + WORDS_TO_BYTES(1)) # else # define ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + WORDS_TO_BYTES(1) - 1) # endif /* * Hash table representation of sets of pages. This assumes it is * OK to add spurious entries to sets. * Used by black-listing code, and perhaps by dirty bit maintenance code. */ # define LOG_PHT_ENTRIES 14 /* Collisions are likely if heap grows */ /* to more than 16K hblks = 64MB. */ /* Each hash table occupies 2K bytes. */ # define PHT_ENTRIES ((word)1 << LOG_PHT_ENTRIES) # define PHT_SIZE (PHT_ENTRIES >> LOGWL) typedef word page_hash_table[PHT_SIZE]; # define PHT_HASH(addr) ((((word)(addr)) >> LOG_HBLKSIZE) & (PHT_ENTRIES - 1)) # define get_pht_entry_from_index(bl, index) \ (((bl)[divWORDSZ(index)] >> modWORDSZ(index)) & 1) # define set_pht_entry_from_index(bl, index) \ (bl)[divWORDSZ(index)] |= (word)1 << modWORDSZ(index) # define clear_pht_entry_from_index(bl, index) \ (bl)[divWORDSZ(index)] &= ~((word)1 << modWORDSZ(index)) /********************************************/ /* */ /* H e a p B l o c k s */ /* */ /********************************************/ /* heap block header */ #define HBLKMASK (HBLKSIZE-1) #define BITS_PER_HBLK (HBLKSIZE * 8) #define MARK_BITS_PER_HBLK (BITS_PER_HBLK/CPP_WORDSZ) /* upper bound */ /* We allocate 1 bit/word. Only the first word */ /* in each object is actually marked. */ # ifdef ALIGN_DOUBLE # define MARK_BITS_SZ (((MARK_BITS_PER_HBLK + 2*CPP_WORDSZ - 1) \ / (2*CPP_WORDSZ))*2) # else # define MARK_BITS_SZ ((MARK_BITS_PER_HBLK + CPP_WORDSZ - 1)/CPP_WORDSZ) # endif /* Upper bound on number of mark words per heap block */ /* Mark stack entries. */ typedef struct ms_entry { word * mse_start; /* inclusive */ word * mse_end; /* exclusive */ } mse; typedef mse * (*mark_proc)(/* word * addr, hdr * hhdr, mse * msp, mse * msl */); /* Procedure to arrange for the descendents of the object at */ /* addr to be marked. Msp points at the top entry on the */ /* mark stack. Msl delimits the hot end of the mark stack. */ /* hhdr is the hdr structure corresponding to addr. */ /* Returns the new mark stack pointer. */ struct hblkhdr { word hb_sz; /* If in use, size in words, of objects in the block. */ /* if free, the size in bytes of the whole block */ struct hblk * hb_next; /* Link field for hblk free list */ /* and for lists of chunks waiting to be */ /* reclaimed. */ mark_proc hb_mark_proc; /* Procedure to mark objects. Can */ /* also be retrived through obj_kind. */ /* But one level of indirection matters */ /* here. */ char* hb_map; /* A pointer to a pointer validity map of the block. */ /* See GC_obj_map. */ /* Valid for all blocks with headers. */ /* Free blocks point to GC_invalid_map. */ unsigned short hb_obj_kind; /* Kind of objects in the block. Each kind */ /* identifies a mark procedure and a set of */ /* list headers. sometimes called regions. */ unsigned short hb_last_reclaimed; /* Value of GC_gc_no when block was */ /* last allocated or swept. May wrap. */ word hb_marks[MARK_BITS_SZ]; /* Bit i in the array refers to the */ /* object starting at the ith word (header */ /* INCLUDED) in the heap block. */ /* The lsb of word 0 is numbered 0. */ }; /* heap block body */ # define DISCARD_WORDS 0 /* Number of words to be dropped at the beginning of each block */ /* Must be a multiple of WORDSZ. May reasonably be nonzero */ /* on machines that don't guarantee longword alignment of */ /* pointers, so that the number of false hits is minimized. */ /* 0 and WORDSZ are probably the only reasonable values. */ # define BODY_SZ ((HBLKSIZE-WORDS_TO_BYTES(DISCARD_WORDS))/sizeof(word)) struct hblk { # if (DISCARD_WORDS != 0) word garbage[DISCARD_WORDS]; # endif word hb_body[BODY_SZ]; }; # define HDR_WORDS ((word)DISCARD_WORDS) # define HDR_BYTES ((word)WORDS_TO_BYTES(DISCARD_WORDS)) # define OBJ_SZ_TO_BLOCKS(sz) \ divHBLKSZ(HDR_BYTES + WORDS_TO_BYTES(sz) + HBLKSIZE-1) /* Size of block (in units of HBLKSIZE) needed to hold objects of */ /* given sz (in words). */ /* Object free list link */ # define obj_link(p) (*(ptr_t *)(p)) /* lists of all heap blocks and free lists */ /* These are grouped together in a struct */ /* so that they can be easily skipped by the */ /* GC_mark routine. */ /* The ordering is weird to make GC_malloc */ /* faster by keeping the important fields */ /* sufficiently close together that a */ /* single load of a base register will do. */ /* Scalars that could easily appear to */ /* be pointers are also put here. */ struct _GC_arrays { word _heapsize; ptr_t _last_heap_addr; ptr_t _prev_heap_addr; word _words_allocd_before_gc; /* Number of words allocated before this */ /* collection cycle. */ # ifdef GATHERSTATS word _composite_in_use; /* Number of words in accessible composite */ /* objects. */ word _atomic_in_use; /* Number of words in accessible atomic */ /* objects. */ # endif word _words_allocd; /* Number of words allocated during this collection cycle */ word _words_wasted; /* Number of words wasted due to internal fragmentation */ /* in large objects allocated since last gc. Approximate.*/ word _non_gc_bytes_at_gc; /* Number of explicitly managed bytes of storage */ /* at last collection. */ word _mem_freed; /* Number of explicitly deallocated words of memory */ /* since last collection. */ ptr_t _objfreelist[MAXOBJSZ+1]; /* free list for objects */ # ifdef MERGE_SIZES unsigned _size_map[WORDS_TO_BYTES(MAXOBJSZ+1)]; /* Number of words to allocate for a given allocation request in */ /* bytes. */ # endif ptr_t _aobjfreelist[MAXOBJSZ+1]; /* free list for atomic objs */ ptr_t _uobjfreelist[MAXOBJSZ+1]; /* uncollectable but traced objs */ # ifdef STUBBORN_ALLOC ptr_t _sobjfreelist[MAXOBJSZ+1]; # endif /* free list for immutable objects */ ptr_t _obj_map[MAXOBJSZ+1]; /* If not NIL, then a pointer to a map of valid */ /* object addresses. hbh_map[sz][i] is j if the */ /* address block_start+i is a valid pointer */ /* to an object at */ /* block_start+i&~3 - WORDS_TO_BYTES(j). */ /* (If ALL_INTERIOR_POINTERS is defined, then */ /* instead ((short *)(hbh_map[sz])[i] is j if */ /* block_start+WORDS_TO_BYTES(i) is in the */ /* interior of an object starting at */ /* block_start+WORDS_TO_BYTES(i-j)). */ /* It is OBJ_INVALID if */ /* block_start+WORDS_TO_BYTES(i) is not */ /* valid as a pointer to an object. */ /* We assume that all values of j <= OBJ_INVALID */ /* The zeroth entry corresponds to large objects.*/ # ifdef ALL_INTERIOR_POINTERS # define map_entry_type short # define OBJ_INVALID 0x7fff # define MAP_ENTRY(map, bytes) \ (((map_entry_type *)(map))[BYTES_TO_WORDS(bytes)]) # define MAP_ENTRIES BYTES_TO_WORDS(HBLKSIZE) # define MAP_SIZE (MAP_ENTRIES * sizeof(map_entry_type)) # define OFFSET_VALID(displ) TRUE # define CPP_MAX_OFFSET (HBLKSIZE - HDR_BYTES - 1) # define MAX_OFFSET ((word)CPP_MAX_OFFSET) # else # define map_entry_type char # define OBJ_INVALID 0x7f # define MAP_ENTRY(map, bytes) \ (map)[bytes] # define MAP_ENTRIES HBLKSIZE # define MAP_SIZE MAP_ENTRIES # define CPP_MAX_OFFSET (WORDS_TO_BYTES(OBJ_INVALID) - 1) # define MAX_OFFSET ((word)CPP_MAX_OFFSET) # define VALID_OFFSET_SZ \ (CPP_MAX_OFFSET > WORDS_TO_BYTES(CPP_MAXOBJSZ)? \ CPP_MAX_OFFSET+1 \ : WORDS_TO_BYTES(CPP_MAXOBJSZ)+1) char _valid_offsets[VALID_OFFSET_SZ]; /* GC_valid_offsets[i] == TRUE ==> i */ /* is registered as a displacement. */ # define OFFSET_VALID(displ) GC_valid_offsets[displ] char _modws_valid_offsets[sizeof(word)]; /* GC_valid_offsets[i] ==> */ /* GC_modws_valid_offsets[i%sizeof(word)] */ # endif struct hblk * _reclaim_list[MAXOBJSZ+1]; struct hblk * _areclaim_list[MAXOBJSZ+1]; struct hblk * _ureclaim_list[MAXOBJSZ+1]; # ifdef STUBBORN_ALLOC struct hblk * _sreclaim_list[MAXOBJSZ+1]; page_hash_table _changed_pages; /* Stubborn object pages that were changes since last call to */ /* GC_read_changed. */ page_hash_table _prev_changed_pages; /* Stubborn object pages that were changes before last call to */ /* GC_read_changed. */ # endif # if defined(PROC_VDB) || defined(MPROTECT_VDB) page_hash_table _grungy_pages; /* Pages that were dirty at last */ /* GC_read_dirty. */ # endif # define MAX_HEAP_SECTS 256 /* Separately added heap sections. */ struct HeapSect { ptr_t hs_start; word hs_bytes; } _heap_sects[MAX_HEAP_SECTS]; /* Block header index; see gc_headers.h */ bottom_index _all_nils; bottom_index * _top_index [TOP_SZ]; }; extern struct _GC_arrays GC_arrays; # define GC_objfreelist GC_arrays._objfreelist # define GC_aobjfreelist GC_arrays._aobjfreelist # define GC_uobjfreelist GC_arrays._uobjfreelist # define GC_sobjfreelist GC_arrays._sobjfreelist # define GC_valid_offsets GC_arrays._valid_offsets # define GC_modws_valid_offsets GC_arrays._modws_valid_offsets # define GC_reclaim_list GC_arrays._reclaim_list # define GC_areclaim_list GC_arrays._areclaim_list # define GC_ureclaim_list GC_arrays._ureclaim_list # ifdef STUBBORN_ALLOC # define GC_sreclaim_list GC_arrays._sreclaim_list # define GC_changed_pages GC_arrays._changed_pages # define GC_prev_changed_pages GC_arrays._prev_changed_pages # endif # define GC_obj_map GC_arrays._obj_map # define GC_last_heap_addr GC_arrays._last_heap_addr # define GC_prev_heap_addr GC_arrays._prev_heap_addr # define GC_words_allocd GC_arrays._words_allocd # define GC_words_wasted GC_arrays._words_wasted # define GC_non_gc_bytes_at_gc GC_arrays._non_gc_bytes_at_gc # define GC_mem_freed GC_arrays._mem_freed # define GC_heapsize GC_arrays._heapsize # define GC_words_allocd_before_gc GC_arrays._words_allocd_before_gc # define GC_heap_sects GC_arrays._heap_sects # define GC_all_nils GC_arrays._all_nils # define GC_top_index GC_arrays._top_index # if defined(PROC_VDB) || defined(MPROTECT_VDB) # define GC_grungy_pages GC_arrays._grungy_pages # endif # ifdef GATHERSTATS # define GC_composite_in_use GC_arrays._composite_in_use # define GC_atomic_in_use GC_arrays._atomic_in_use # endif # ifdef MERGE_SIZES # define GC_size_map GC_arrays._size_map # endif # define beginGC_arrays ((ptr_t)(&GC_arrays)) # define endGC_arrays (((ptr_t)(&GC_arrays)) + (sizeof GC_arrays)) # define MAXOBJKINDS 16 /* Object kinds: */ extern struct obj_kind { ptr_t *ok_freelist; /* Array of free listheaders for this kind of object */ /* Point either to GC_arrays or to storage allocated */ /* with GC_scratch_alloc. */ struct hblk **ok_reclaim_list; /* List headers for lists of blocks waiting to be */ /* swept. */ mark_proc ok_mark_proc; /* Procedure to either mark referenced objects, */ /* or push them on the mark stack. */ bool ok_init; /* Clear objects before putting them on the free list. */ } GC_obj_kinds[MAXOBJKINDS]; /* Predefined kinds: */ # define PTRFREE 0 # define NORMAL 1 # define UNCOLLECTABLE 2 # define STUBBORN 3 extern word GC_n_heap_sects; /* Number of separately added heap */ /* sections. */ extern int GC_n_kinds; extern char * GC_invalid_map; /* Pointer to the nowhere valid hblk map */ /* Blocks pointing to this map are free. */ extern struct hblk * GC_hblkfreelist; /* List of completely empty heap blocks */ /* Linked through hb_next field of */ /* header structure associated with */ /* block. */ extern bool GC_is_initialized; /* GC_init() has been run. */ extern bool GC_objects_are_marked; /* There are marked objects in */ /* the heap. */ # ifndef PCR extern ptr_t GC_stackbottom; /* Cool end of user stack */ # endif extern word GC_hincr; /* current heap increment, in blocks */ extern word GC_root_size; /* Total size of registered root sections */ extern bool GC_debugging_started; /* GC_debug_malloc has been called. */ extern ptr_t GC_least_plausible_heap_addr; extern ptr_t GC_greatest_plausible_heap_addr; /* Bounds on the heap. Guaranteed valid */ /* Likely to include future heap expansion. */ /* Operations */ # define update_GC_hincr GC_hincr = (GC_hincr * HINCR_MULT)/HINCR_DIV; \ if (GC_hincr > MAXHINCR) {GC_hincr = MAXHINCR;} # ifndef abs # define abs(x) ((x) < 0? (-(x)) : (x)) # endif /* Marks are in a reserved area in */ /* each heap block. Each word has one mark bit associated */ /* with it. Only those corresponding to the beginning of an */ /* object are used. */ /* Mark bit perations */ /* * Retrieve, set, clear the mark bit corresponding * to the nth word in a given heap block. * * (Recall that bit n corresponds to object beginning at word n * relative to the beginning of the block, including unused words) */ # define mark_bit_from_hdr(hhdr,n) (((hhdr)->hb_marks[divWORDSZ(n)] \ >> (modWORDSZ(n))) & (word)1) # define set_mark_bit_from_hdr(hhdr,n) (hhdr)->hb_marks[divWORDSZ(n)] \ |= (word)1 << modWORDSZ(n) # define clear_mark_bit_from_hdr(hhdr,n) (hhdr)->hb_marks[divWORDSZ(n)] \ &= ~((word)1 << modWORDSZ(n)) /* Important internal collector routines */ void GC_apply_to_all_blocks(/*fn, client_data*/); /* Invoke fn(hbp, client_data) for each */ /* allocated heap block. */ struct hblk * GC_next_block(/* struct hblk * h */); mse * GC_no_mark_proc(/*addr,hhdr,msp,msl*/); /* Mark procedure for PTRFREE objects. */ mse * GC_normal_mark_proc(/*addr,hhdr,msp,msl*/); /* Mark procedure for NORMAL objects. */ void GC_mark_init(); void GC_clear_marks(); /* Clear mark bits for all heap objects. */ void GC_mark_from_mark_stack(); /* Mark from everything on the mark stack. */ /* Return after about one pages worth of */ /* work. */ bool GC_mark_stack_empty(); bool GC_mark_some(); /* Perform about one pages worth of marking */ /* work of whatever kind is needed. Returns */ /* quickly if no collection is in progress. */ /* Return TRUE if mark phase finished. */ void GC_initiate_full(); /* initiate full collection. */ void GC_initiate_partial(); /* initiate partial collection. */ void GC_push_all(/*b,t*/); /* Push everything in a range */ /* onto mark stack. */ void GC_push_dirty(/*b,t*/); /* Push all possibly changed */ /* subintervals of [b,t) onto */ /* mark stack. */ void GC_push_conditional(/* ptr_t b, ptr_t t, bool all*/); /* Do either of the above, depending */ /* on the third arg. */ void GC_push_all_stack(/*b,t*/); /* As above, but consider */ /* interior pointers as valid */ void GC_remark(); /* Mark from all marked objects. Used */ /* only if we had to drop something. */ void GC_push_one(/*p*/); /* If p points to an object, mark it */ /* and push contents on the mark stack */ void GC_push_one_checked(/*p*/); /* Ditto, omits plausibility test */ void GC_push_marked(/* struct hblk h, hdr * hhdr */); /* Push contents of all marked objects in h onto */ /* mark stack. */ struct hblk * GC_push_next_marked_dirty(/* h */); /* Invoke GC_push_marked on next dirty block above h. */ /* Return a pointer just past the end of this block. */ struct hblk * GC_push_next_marked(/* h */); /* Ditto, but also mark from clean pages. */ struct hblk * GC_push_next_marked_uncollectable(/* h */); /* Ditto, but mark only from uncollectable pages. */ void GC_stopped_mark(); /* Mark from all roots and rescuers */ /* with the world stopped. */ void GC_clear_hdr_marks(/* hhdr */); /* Clear the mark bits in a header */ void GC_add_roots_inner(); void GC_register_dynamic_libraries(); /* Add dynamic library data sections to the root set. */ /* Machine dependent startup routines */ ptr_t GC_get_stack_base(); void GC_register_data_segments(); # ifndef ALL_INTERIOR_POINTERS void GC_add_to_black_list_normal(/* bits */); /* Register bits as a possible future false */ /* reference from the heap or static data */ # define GC_ADD_TO_BLACK_LIST_NORMAL(bits) GC_add_to_black_list_normal(bits) # else # define GC_ADD_TO_BLACK_LIST_NORMAL(bits) GC_add_to_black_list_stack(bits) # endif void GC_add_to_black_list_stack(/* bits */); struct hblk * GC_is_black_listed(/* h, len */); /* If there are likely to be false references */ /* to a block starting at h of the indicated */ /* length, then return the next plausible */ /* starting location for h that might avoid */ /* these false references. */ void GC_promote_black_lists(); /* Declare an end to a black listing phase. */ ptr_t GC_scratch_alloc(/*bytes*/); /* GC internal memory allocation for */ /* small objects. Deallocation is not */ /* possible. */ void GC_invalidate_map(/* hdr */); /* Remove the object map associated */ /* with the block. This identifies */ /* the block as invalid to the mark */ /* routines. */ bool GC_add_map_entry(/*sz*/); /* Add a heap block map for objects of */ /* size sz to obj_map. */ /* Return FALSE on failure. */ void GC_register_displacement_inner(/*offset*/); /* Version of GC_register_displacement */ /* that assumes lock is already held */ /* and signals are already disabled. */ void GC_init_inner(); void GC_new_hblk(/*size_in_words, kind*/); /* Allocate a new heap block, and build */ /* a free list in it. */ struct hblk * GC_allochblk(/*size_in_words, kind*/); /* Allocate a heap block, clear it if */ /* for composite objects, inform */ /* the marker that block is valid */ /* for objects of indicated size. */ /* sz < 0 ==> atomic. */ void GC_freehblk(); /* Deallocate a heap block and mark it */ /* as invalid. */ void GC_start_reclaim(/*abort_if_found*/); /* Restore unmarked objects to free */ /* lists, or (if abort_if_found is */ /* TRUE) report them. */ /* Sweeping of small object pages is */ /* largely deferred. */ void GC_continue_reclaim(/*size, kind*/); /* Sweep pages of the given size and */ /* kind, as long as possible, and */ /* as long as the corr. free list is */ /* empty. */ void GC_reclaim_or_delete_all(); /* Arrange for all reclaim lists to be */ /* empty. Judiciously choose between */ /* sweeping and discarding each page. */ bool GC_gcollect_inner(); /* Collect; caller must have acquired */ /* lock and disabled signals. */ /* FALSE return indicates nothing was */ /* done due to insufficient allocation. */ void GC_finish_collection(); /* Finish collection. Mark bits are */ /* consistent and lock is still held. */ bool GC_collect_or_expand(/* needed_blocks */); /* Collect or expand heap in an attempt */ /* make the indicated number of free */ /* blocks available. Should be called */ /* until it fails by returning FALSE. */ void GC_init(); /* Initialize collector. */ void GC_collect_a_little(/* n */); /* Do n units worth of garbage */ /* collection work, if appropriate. */ /* A unit is an amount appropriate for */ /* HBLKSIZE bytes of allocation. */ ptr_t GC_generic_malloc(/* bytes, kind */); /* Allocate an object of the given */ /* kind. By default, there are only */ /* two kinds: composite, and atomic. */ /* We claim it's possible for clever */ /* client code that understands GC */ /* internals to add more, e.g. to */ /* communicate object layout info */ /* to the collector. */ ptr_t GC_generic_malloc_inner(/* bytes, kind */); /* Ditto, but I already hold lock, etc. */ ptr_t GC_generic_malloc_words_small(/*words, kind*/); /* As above, but size in units of words */ /* Bypasses MERGE_SIZES. Assumes */ /* words <= MAXOBJSZ. */ ptr_t GC_allocobj(/* sz_inn_words, kind */); /* Make the indicated */ /* free list nonempty, and return its */ /* head. */ bool GC_install_header(/*h*/); /* Install a header for block h. */ /* Return FALSE on failure. */ bool GC_install_counts(/*h, sz*/); /* Set up forwarding counts for block */ /* h of size sz. */ /* Return FALSE on failure. */ void GC_remove_header(/*h*/); /* Remove the header for block h. */ void GC_remove_counts(/*h, sz*/); /* Remove forwarding counts for h. */ hdr * GC_find_header(/*p*/); /* Debugging only. */ void GC_finalize(); /* Perform all indicated finalization actions */ /* on unmarked objects. */ void GC_add_to_heap(/*p, bytes*/); /* Add a HBLKSIZE aligned chunk to the heap. */ void GC_print_obj(/* ptr_t p */); /* P points to somewhere inside an object with */ /* debugging info. Print a human readable */ /* description of the object to stderr. */ extern void (*GC_check_heap)(); /* Check that all objects in the heap with */ /* debugging info are intact. Print */ /* descriptions of any that are not. */ /* Virtual dirty bit implementation: */ /* Each implementation exports the following: */ void GC_read_dirty(); /* Retrueve dirty bits. */ bool GC_page_was_dirty(/* struct hblk * h */); /* Read retrieved dirty bits. */ void GC_write_hint(/* struct hblk * h */); /* h is about to be written. */ void GC_dirty_init(); /* Slow/general mark bit manipulation: */ bool GC_is_marked(); void GC_clear_mark_bit(); void GC_set_mark_bit(); /* Stubborn objects: */ void GC_read_changed(); /* Analogous to GC_read_dirty */ bool GC_page_was_changed(/* h */); /* Analogous to GC_page_was_dirty */ void GC_clean_changing_list(); /* Collect obsolete changing list entries */ void GC_stubborn_init(); /* Debugging print routines: */ void GC_print_block_list(); void GC_print_hblkfreelist(); /* Logging and diagnostic output: */ void GC_printf(/* format, a, b, c, d, e, f */); /* A version of printf that doesn't allocate, */ /* is restricted to long arguments, and */ /* (unfortunately) doesn't use varargs for */ /* portability. Restricted to 6 args and */ /* 1K total output length. */ /* (We use sprintf. Hopefully that doesn't */ /* allocate for long arguments.) */ # define GC_printf0(f) GC_printf(f, 0l, 0l, 0l, 0l, 0l, 0l) # define GC_printf1(f,a) GC_printf(f, (long)a, 0l, 0l, 0l, 0l, 0l) # define GC_printf2(f,a,b) GC_printf(f, (long)a, (long)b, 0l, 0l, 0l, 0l) # define GC_printf3(f,a,b,c) GC_printf(f, (long)a, (long)b, (long)c, 0l, 0l, 0l) # define GC_printf4(f,a,b,c,d) GC_printf(f, (long)a, (long)b, (long)c, \ (long)d, 0l, 0l) # define GC_printf5(f,a,b,c,d,e) GC_printf(f, (long)a, (long)b, (long)c, \ (long)d, (long)e, 0l) # define GC_printf6(f,a,b,c,d,e,g) GC_printf(f, (long)a, (long)b, (long)c, \ (long)d, (long)e, (long)g) void GC_err_printf(/* format, a, b, c, d, e, f */); # define GC_err_printf0(f) GC_err_puts(f) # define GC_err_printf1(f,a) GC_err_printf(f, (long)a, 0l, 0l, 0l, 0l, 0l) # define GC_err_printf2(f,a,b) GC_err_printf(f, (long)a, (long)b, 0l, 0l, 0l, 0l) # define GC_err_printf3(f,a,b,c) GC_err_printf(f, (long)a, (long)b, (long)c, \ 0l, 0l, 0l) # define GC_err_printf4(f,a,b,c,d) GC_err_printf(f, (long)a, (long)b, \ (long)c, (long)d, 0l, 0l) # define GC_err_printf5(f,a,b,c,d,e) GC_err_printf(f, (long)a, (long)b, \ (long)c, (long)d, \ (long)e, 0l) # define GC_err_printf6(f,a,b,c,d,e,g) GC_err_printf(f, (long)a, (long)b, \ (long)c, (long)d, \ (long)e, (long)g) /* Ditto, writes to stderr. */ void GC_err_puts(/* char *s */); /* Write s to stderr, don't buffer, don't add */ /* newlines, don't ... */ # endif /* GC_PRIVATE_H */