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Diffstat (limited to 'gc/gc_mark.h')
| -rw-r--r-- | gc/gc_mark.h | 280 |
1 files changed, 0 insertions, 280 deletions
diff --git a/gc/gc_mark.h b/gc/gc_mark.h deleted file mode 100644 index 4628323..0000000 --- a/gc/gc_mark.h +++ /dev/null @@ -1,280 +0,0 @@ -/* - * Copyright (c) 1991-1994 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 use or copy this program - * for any purpose, provided the above notices are retained on all copies. - * Permission to modify the code and to distribute modified code is granted, - * provided the above notices are retained, and a notice that the code was - * modified is included with the above copyright notice. - * - */ -/* Boehm, November 7, 1994 4:56 pm PST */ - -/* - * Declarations of mark stack. Needed by marker and client supplied mark - * routines. To be included after gc_priv.h. - */ -#ifndef GC_MARK_H -# define GC_MARK_H - -/* A client supplied mark procedure. Returns new mark stack pointer. */ -/* Primary effect should be to push new entries on the mark stack. */ -/* Mark stack pointer values are passed and returned explicitly. */ -/* Global variables decribing mark stack are not necessarily valid. */ -/* (This usually saves a few cycles by keeping things in registers.) */ -/* Assumed to scan about PROC_BYTES on average. If it needs to do */ -/* much more work than that, it should do it in smaller pieces by */ -/* pushing itself back on the mark stack. */ -/* Note that it should always do some work (defined as marking some */ -/* objects) before pushing more than one entry on the mark stack. */ -/* This is required to ensure termination in the event of mark stack */ -/* overflows. */ -/* This procedure is always called with at least one empty entry on the */ -/* mark stack. */ -/* Currently we require that mark procedures look for pointers in a */ -/* subset of the places the conservative marker would. It must be safe */ -/* to invoke the normal mark procedure instead. */ -# define PROC_BYTES 100 -/* The real declarations of the following are in gc_priv.h, so that */ -/* we can avoid scanning the following table. */ -/* -typedef struct ms_entry * (*mark_proc)( word * addr, mark_stack_ptr, - mark_stack_limit, env ); - -# define LOG_MAX_MARK_PROCS 6 -# define MAX_MARK_PROCS (1 << LOG_MAX_MARK_PROCS) -extern mark_proc GC_mark_procs[MAX_MARK_PROCS]; -*/ - -extern word GC_n_mark_procs; - -/* Object descriptors on mark stack or in objects. Low order two */ -/* bits are tags distinguishing among the following 4 possibilities */ -/* for the high order 30 bits. */ -#define DS_TAG_BITS 2 -#define DS_TAGS ((1 << DS_TAG_BITS) - 1) -#define DS_LENGTH 0 /* The entire word is a length in bytes that */ - /* must be a multiple of 4. */ -#define DS_BITMAP 1 /* 30 bits are a bitmap describing pointer */ - /* fields. The msb is 1 iff the first word */ - /* is a pointer. */ - /* (This unconventional ordering sometimes */ - /* makes the marker slightly faster.) */ - /* Zeroes indicate definite nonpointers. Ones */ - /* indicate possible pointers. */ - /* Only usable if pointers are word aligned. */ -# define BITMAP_BITS (WORDSZ - DS_TAG_BITS) -#define DS_PROC 2 - /* The objects referenced by this object can be */ - /* pushed on the mark stack by invoking */ - /* PROC(descr). ENV(descr) is passed as the */ - /* last argument. */ -# define PROC(descr) \ - (GC_mark_procs[((descr) >> DS_TAG_BITS) & (MAX_MARK_PROCS-1)]) -# define ENV(descr) \ - ((descr) >> (DS_TAG_BITS + LOG_MAX_MARK_PROCS)) -# define MAX_ENV \ - (((word)1 << (WORDSZ - DS_TAG_BITS - LOG_MAX_MARK_PROCS)) - 1) -# define MAKE_PROC(proc_index, env) \ - (((((env) << LOG_MAX_MARK_PROCS) | (proc_index)) << DS_TAG_BITS) \ - | DS_PROC) -#define DS_PER_OBJECT 3 /* The real descriptor is at the */ - /* byte displacement from the beginning of the */ - /* object given by descr & ~DS_TAGS */ - -typedef struct ms_entry { - word * mse_start; /* First word of object */ - word mse_descr; /* Descriptor; low order two bits are tags, */ - /* identifying the upper 30 bits as one of the */ - /* following: */ -} mse; - -extern word GC_mark_stack_size; - -extern mse * GC_mark_stack_top; - -extern mse * GC_mark_stack; - -word GC_find_start(); - -mse * GC_signal_mark_stack_overflow(); - -# ifdef GATHERSTATS -# define ADD_TO_ATOMIC(sz) GC_atomic_in_use += (sz) -# define ADD_TO_COMPOSITE(sz) GC_composite_in_use += (sz) -# else -# define ADD_TO_ATOMIC(sz) -# define ADD_TO_COMPOSITE(sz) -# endif - -/* Push the object obj with corresponding heap block header hhdr onto */ -/* the mark stack. */ -# define PUSH_OBJ(obj, hhdr, mark_stack_top, mark_stack_limit) \ -{ \ - register word _descr = (hhdr) -> hb_descr; \ - \ - if (_descr == 0) { \ - ADD_TO_ATOMIC((hhdr) -> hb_sz); \ - } else { \ - ADD_TO_COMPOSITE((hhdr) -> hb_sz); \ - mark_stack_top++; \ - if (mark_stack_top >= mark_stack_limit) { \ - mark_stack_top = GC_signal_mark_stack_overflow(mark_stack_top); \ - } \ - mark_stack_top -> mse_start = (obj); \ - mark_stack_top -> mse_descr = _descr; \ - } \ -} - -#ifdef PRINT_BLACK_LIST -# define GC_FIND_START(current, hhdr, source) \ - GC_find_start(current, hhdr, source) -#else -# define GC_FIND_START(current, hhdr, source) \ - GC_find_start(current, hhdr) -#endif - -/* Push the contents of current onto the mark stack if it is a valid */ -/* ptr to a currently unmarked object. Mark it. */ -/* If we assumed a standard-conforming compiler, we could probably */ -/* generate the exit_label transparently. */ -# define PUSH_CONTENTS(current, mark_stack_top, mark_stack_limit, \ - source, exit_label) \ -{ \ - register int displ; /* Displacement in block; first bytes, then words */ \ - register hdr * hhdr; \ - register map_entry_type map_entry; \ - \ - GET_HDR(current,hhdr); \ - if (IS_FORWARDING_ADDR_OR_NIL(hhdr)) { \ - current = GC_FIND_START(current, hhdr, (word)source); \ - if (current == 0) goto exit_label; \ - hhdr = HDR(current); \ - } \ - displ = HBLKDISPL(current); \ - map_entry = MAP_ENTRY((hhdr -> hb_map), displ); \ - if (map_entry == OBJ_INVALID) { \ - GC_ADD_TO_BLACK_LIST_NORMAL(current, source); goto exit_label; \ - } \ - displ = BYTES_TO_WORDS(displ); \ - displ -= map_entry; \ - \ - { \ - register word * mark_word_addr = hhdr -> hb_marks + divWORDSZ(displ); \ - register word mark_word = *mark_word_addr; \ - register word mark_bit = (word)1 << modWORDSZ(displ); \ - \ - if (mark_word & mark_bit) { \ - /* Mark bit is already set */ \ - goto exit_label; \ - } \ - GC_STORE_BACK_PTR((ptr_t)source, (ptr_t)HBLKPTR(current) \ - + WORDS_TO_BYTES(displ)); \ - *mark_word_addr = mark_word | mark_bit; \ - } \ - PUSH_OBJ(((word *)(HBLKPTR(current)) + displ), hhdr, \ - mark_stack_top, mark_stack_limit) \ - exit_label: ; \ -} - -#ifdef PRINT_BLACK_LIST -# define PUSH_ONE_CHECKED(p, ip, source) \ - GC_push_one_checked(p, ip, (ptr_t)(source)) -#else -# define PUSH_ONE_CHECKED(p, ip, source) \ - GC_push_one_checked(p, ip) -#endif - -/* - * Push a single value onto mark stack. Mark from the object pointed to by p. - * P is considered valid even if it is an interior pointer. - * Previously marked objects are not pushed. Hence we make progress even - * if the mark stack overflows. - */ -# define GC_PUSH_ONE_STACK(p, source) \ - if ((ptr_t)(p) >= GC_least_plausible_heap_addr \ - && (ptr_t)(p) < GC_greatest_plausible_heap_addr) { \ - PUSH_ONE_CHECKED(p, TRUE, source); \ - } - -/* - * As above, but interior pointer recognition as for - * normal for heap pointers. - */ -# ifdef ALL_INTERIOR_POINTERS -# define AIP TRUE -# else -# define AIP FALSE -# endif -# define GC_PUSH_ONE_HEAP(p,source) \ - if ((ptr_t)(p) >= GC_least_plausible_heap_addr \ - && (ptr_t)(p) < GC_greatest_plausible_heap_addr) { \ - PUSH_ONE_CHECKED(p,AIP,source); \ - } - -/* - * Mark from one finalizable object using the specified - * mark proc. May not mark the object pointed to by - * real_ptr. That is the job of the caller, if appropriate - */ -# define GC_MARK_FO(real_ptr, mark_proc) \ -{ \ - (*(mark_proc))(real_ptr); \ - while (!GC_mark_stack_empty()) GC_mark_from_mark_stack(); \ - if (GC_mark_state != MS_NONE) { \ - GC_set_mark_bit(real_ptr); \ - while (!GC_mark_some((ptr_t)0)); \ - } \ -} - -extern GC_bool GC_mark_stack_too_small; - /* We need a larger mark stack. May be */ - /* set by client supplied mark routines.*/ - -typedef int mark_state_t; /* Current state of marking, as follows:*/ - /* Used to remember where we are during */ - /* concurrent marking. */ - - /* We say something is dirty if it was */ - /* written since the last time we */ - /* retrieved dirty bits. We say it's */ - /* grungy if it was marked dirty in the */ - /* last set of bits we retrieved. */ - - /* Invariant I: all roots and marked */ - /* objects p are either dirty, or point */ - /* to objects q that are either marked */ - /* or a pointer to q appears in a range */ - /* on the mark stack. */ - -# define MS_NONE 0 /* No marking in progress. I holds. */ - /* Mark stack is empty. */ - -# define MS_PUSH_RESCUERS 1 /* Rescuing objects are currently */ - /* being pushed. I holds, except */ - /* that grungy roots may point to */ - /* unmarked objects, as may marked */ - /* grungy objects above scan_ptr. */ - -# define MS_PUSH_UNCOLLECTABLE 2 - /* I holds, except that marked */ - /* uncollectable objects above scan_ptr */ - /* may point to unmarked objects. */ - /* Roots may point to unmarked objects */ - -# define MS_ROOTS_PUSHED 3 /* I holds, mark stack may be nonempty */ - -# define MS_PARTIALLY_INVALID 4 /* I may not hold, e.g. because of M.S. */ - /* overflow. However marked heap */ - /* objects below scan_ptr point to */ - /* marked or stacked objects. */ - -# define MS_INVALID 5 /* I may not hold. */ - -extern mark_state_t GC_mark_state; - -#endif /* GC_MARK_H */ - |