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Diffstat (limited to '')
| -rw-r--r-- | gc/include/private/gc_pmark.h | 379 |
1 files changed, 0 insertions, 379 deletions
diff --git a/gc/include/private/gc_pmark.h b/gc/include/private/gc_pmark.h deleted file mode 100644 index cf85d4d..0000000 --- a/gc/include/private/gc_pmark.h +++ /dev/null @@ -1,379 +0,0 @@ -/* - * Copyright (c) 1991-1994 by Xerox Corporation. All rights reserved. - * Copyright (c) 2001 by Hewlett-Packard Company. 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. - * - */ - -/* Private declarations of GC marker data structures and macros */ - -/* - * Declarations of mark stack. Needed by marker and client supplied mark - * routines. Transitively include gc_priv.h. - * (Note that gc_priv.h should not be included before this, since this - * includes dbg_mlc.h, which wants to include gc_priv.h AFTER defining - * I_HIDE_POINTERS.) - */ -#ifndef GC_PMARK_H -# define GC_PMARK_H - -# if defined(KEEP_BACK_PTRS) || defined(PRINT_BLACK_LIST) -# include "dbg_mlc.h" -# endif -# ifndef GC_MARK_H -# include "../gc_mark.h" -# endif -# ifndef GC_PRIVATE_H -# include "gc_priv.h" -# endif - -/* The real declarations of the following is in gc_priv.h, so that */ -/* we can avoid scanning the following table. */ -/* -extern mark_proc GC_mark_procs[MAX_MARK_PROCS]; -*/ - -/* - * Mark descriptor stuff that should remain private for now, mostly - * because it's hard to export WORDSZ without including gcconfig.h. - */ -# define BITMAP_BITS (WORDSZ - GC_DS_TAG_BITS) -# define PROC(descr) \ - (GC_mark_procs[((descr) >> GC_DS_TAG_BITS) & (GC_MAX_MARK_PROCS-1)]) -# define ENV(descr) \ - ((descr) >> (GC_DS_TAG_BITS + GC_LOG_MAX_MARK_PROCS)) -# define MAX_ENV \ - (((word)1 << (WORDSZ - GC_DS_TAG_BITS - GC_LOG_MAX_MARK_PROCS)) - 1) - - -extern word GC_n_mark_procs; - -/* Number of mark stack entries to discard on overflow. */ -#define GC_MARK_STACK_DISCARDS (INITIAL_MARK_STACK_SIZE/8) - -typedef struct GC_ms_entry { - GC_word * mse_start; /* First word of object */ - GC_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_limit; - -#ifdef PARALLEL_MARK - extern mse * VOLATILE GC_mark_stack_top; -#else - extern mse * GC_mark_stack_top; -#endif - -extern mse * GC_mark_stack; - -#ifdef PARALLEL_MARK - /* - * Allow multiple threads to participate in the marking process. - * This works roughly as follows: - * The main mark stack never shrinks, but it can grow. - * - * The initiating threads holds the GC lock, and sets GC_help_wanted. - * - * Other threads: - * 1) update helper_count (while holding mark_lock.) - * 2) allocate a local mark stack - * repeatedly: - * 3) Steal a global mark stack entry by atomically replacing - * its descriptor with 0. - * 4) Copy it to the local stack. - * 5) Mark on the local stack until it is empty, or - * it may be profitable to copy it back. - * 6) If necessary, copy local stack to global one, - * holding mark lock. - * 7) Stop when the global mark stack is empty. - * 8) decrement helper_count (holding mark_lock). - * - * This is an experiment to see if we can do something along the lines - * of the University of Tokyo SGC in a less intrusive, though probably - * also less performant, way. - */ - void GC_do_parallel_mark(); - /* inititate parallel marking. */ - - extern GC_bool GC_help_wanted; /* Protected by mark lock */ - extern unsigned GC_helper_count; /* Number of running helpers. */ - /* Protected by mark lock */ - extern unsigned GC_active_count; /* Number of active helpers. */ - /* Protected by mark lock */ - /* May increase and decrease */ - /* within each mark cycle. But */ - /* once it returns to 0, it */ - /* stays zero for the cycle. */ - /* GC_mark_stack_top is also protected by mark lock. */ - extern mse * VOLATILE GC_first_nonempty; - /* Lowest entry on mark stack */ - /* that may be nonempty. */ - /* Updated only by initiating */ - /* thread. */ - /* - * GC_notify_all_marker() is used when GC_help_wanted is first set, - * when the last helper becomes inactive, - * when something is added to the global mark stack, and just after - * GC_mark_no is incremented. - * This could be split into multiple CVs (and probably should be to - * scale to really large numbers of processors.) - */ -#endif /* PARALLEL_MARK */ - -/* Return a pointer to within 1st page of object. */ -/* Set *new_hdr_p to corr. hdr. */ -#ifdef __STDC__ -# ifdef PRINT_BLACK_LIST - ptr_t GC_find_start(ptr_t current, hdr *hhdr, hdr **new_hdr_p, - word source); -# else - ptr_t GC_find_start(ptr_t current, hdr *hhdr, hdr **new_hdr_p); -# endif -#else - ptr_t GC_find_start(); -#endif - -mse * GC_signal_mark_stack_overflow GC_PROTO((mse *msp)); - -# 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; \ - } \ -} - -/* 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) \ -{ \ - hdr * my_hhdr; \ - ptr_t my_current = current; \ - \ - GET_HDR(my_current, my_hhdr); \ - if (IS_FORWARDING_ADDR_OR_NIL(my_hhdr)) { \ - hdr * new_hdr = GC_invalid_header; \ - my_current = GC_find_start(my_current, my_hhdr, &new_hdr); \ - my_hhdr = new_hdr; \ - } \ - PUSH_CONTENTS_HDR(my_current, mark_stack_top, mark_stack_limit, \ - source, exit_label, my_hhdr); \ -exit_label: ; \ -} - -/* As above, but use header cache for header lookup. */ -# define HC_PUSH_CONTENTS(current, mark_stack_top, mark_stack_limit, \ - source, exit_label) \ -{ \ - hdr * my_hhdr; \ - ptr_t my_current = current; \ - \ - HC_GET_HDR(my_current, my_hhdr, source); \ - PUSH_CONTENTS_HDR(my_current, mark_stack_top, mark_stack_limit, \ - source, exit_label, my_hhdr); \ -exit_label: ; \ -} - -/* Set mark bit, exit if it was already set. */ - -# ifdef USE_MARK_BYTES - /* Unlike the mark bit case, there is a race here, and we may set */ - /* the bit twice in the concurrent case. This can result in the */ - /* object being pushed twice. But that's only a performance issue. */ -# define SET_MARK_BIT_EXIT_IF_SET(hhdr,displ,exit_label) \ - { \ - register VOLATILE char * mark_byte_addr = \ - hhdr -> hb_marks + ((displ) >> 1); \ - register char mark_byte = *mark_byte_addr; \ - \ - if (mark_byte) goto exit_label; \ - *mark_byte_addr = 1; \ - } -# else -# define SET_MARK_BIT_EXIT_IF_SET(hhdr,displ,exit_label) \ - { \ - register word * mark_word_addr = hhdr -> hb_marks + divWORDSZ(displ); \ - \ - OR_WORD_EXIT_IF_SET(mark_word_addr, (word)1 << modWORDSZ(displ), \ - exit_label); \ - } -# endif /* USE_MARK_BYTES */ - -/* If the mark bit corresponding to current is not set, set it, and */ -/* push the contents of the object on the mark stack. For a small */ -/* object we assume that current is the (possibly interior) pointer */ -/* to the object. For large objects we assume that current points */ -/* to somewhere inside the first page of the object. If */ -/* GC_all_interior_pointers is set, it may have been previously */ -/* adjusted to make that true. */ -# define PUSH_CONTENTS_HDR(current, mark_stack_top, mark_stack_limit, \ - source, exit_label, hhdr) \ -{ \ - int displ; /* Displacement in block; first bytes, then words */ \ - int map_entry; \ - \ - displ = HBLKDISPL(current); \ - map_entry = MAP_ENTRY((hhdr -> hb_map), displ); \ - displ = BYTES_TO_WORDS(displ); \ - if (map_entry > CPP_MAX_OFFSET) { \ - if (map_entry == OFFSET_TOO_BIG) { \ - map_entry = displ % (hhdr -> hb_sz); \ - displ -= map_entry; \ - if (displ + (hhdr -> hb_sz) > BYTES_TO_WORDS(HBLKSIZE)) { \ - GC_ADD_TO_BLACK_LIST_NORMAL((word)current, source); \ - goto exit_label; \ - } \ - } else { \ - GC_ADD_TO_BLACK_LIST_NORMAL((word)current, source); goto exit_label; \ - } \ - } else { \ - displ -= map_entry; \ - } \ - GC_ASSERT(displ >= 0 && displ < MARK_BITS_PER_HBLK); \ - SET_MARK_BIT_EXIT_IF_SET(hhdr, displ, exit_label); \ - GC_STORE_BACK_PTR((ptr_t)source, (ptr_t)HBLKPTR(current) \ - + WORDS_TO_BYTES(displ)); \ - PUSH_OBJ(((word *)(HBLKPTR(current)) + displ), hhdr, \ - mark_stack_top, mark_stack_limit) \ -} - -#if defined(PRINT_BLACK_LIST) || defined(KEEP_BACK_PTRS) -# define PUSH_ONE_CHECKED_STACK(p, source) \ - GC_mark_and_push_stack(p, (ptr_t)(source)) -#else -# define PUSH_ONE_CHECKED_STACK(p, source) \ - GC_mark_and_push_stack(p) -#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) >= (ptr_t)GC_least_plausible_heap_addr \ - && (ptr_t)(p) < (ptr_t)GC_greatest_plausible_heap_addr) { \ - PUSH_ONE_CHECKED_STACK(p, source); \ - } - -/* - * As above, but interior pointer recognition as for - * normal for heap pointers. - */ -# define GC_PUSH_ONE_HEAP(p,source) \ - if ((ptr_t)(p) >= (ptr_t)GC_least_plausible_heap_addr \ - && (ptr_t)(p) < (ptr_t)GC_greatest_plausible_heap_addr) { \ - GC_mark_stack_top = GC_mark_and_push( \ - (GC_PTR)(p), GC_mark_stack_top, \ - GC_mark_stack_limit, (GC_PTR *)(source)); \ - } - -/* Mark starting at mark stack entry top (incl.) down to */ -/* mark stack entry bottom (incl.). Stop after performing */ -/* about one page worth of work. Return the new mark stack */ -/* top entry. */ -mse * GC_mark_from GC_PROTO((mse * top, mse * bottom, mse *limit)); - -#define MARK_FROM_MARK_STACK() \ - GC_mark_stack_top = GC_mark_from(GC_mark_stack_top, \ - GC_mark_stack, \ - GC_mark_stack + GC_mark_stack_size); - -/* - * 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()) 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_PMARK_H */ - |