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/*
* Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
* Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.
* Copyright (c) 1997 by Silicon Graphics. All rights reserved.
* Copyright (c) 1999 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.
*/
/*
* This is mostly an internal header file. Typical clients should
* not use it. Clients that define their own object kinds with
* debugging allocators will probably want to include this, however.
* No attempt is made to keep the namespace clean. This should not be
* included from header files that are frequently included by clients.
*/
#ifndef _DBG_MLC_H
#define _DBG_MLC_H
# define I_HIDE_POINTERS
# include "gc_priv.h"
# ifdef KEEP_BACK_PTRS
# include "gc_backptr.h"
# endif
#ifndef HIDE_POINTER
/* Gc.h was previously included, and hence the I_HIDE_POINTERS */
/* definition had no effect. Repeat the gc.h definitions here to */
/* get them anyway. */
typedef GC_word GC_hidden_pointer;
# define HIDE_POINTER(p) (~(GC_hidden_pointer)(p))
# define REVEAL_POINTER(p) ((GC_PTR)(HIDE_POINTER(p)))
#endif /* HIDE_POINTER */
# define START_FLAG ((word)0xfedcedcb)
# define END_FLAG ((word)0xbcdecdef)
/* Stored both one past the end of user object, and one before */
/* the end of the object as seen by the allocator. */
# if defined(KEEP_BACK_PTRS) || defined(PRINT_BLACK_LIST) \
|| defined(MAKE_BACK_GRAPH)
/* Pointer "source"s that aren't real locations. */
/* Used in oh_back_ptr fields and as "source" */
/* argument to some marking functions. */
# define NOT_MARKED (ptr_t)(0)
# define MARKED_FOR_FINALIZATION (ptr_t)(2)
/* Object was marked because it is finalizable. */
# define MARKED_FROM_REGISTER (ptr_t)(4)
/* Object was marked from a rgister. Hence the */
/* source of the reference doesn't have an address. */
# endif /* KEEP_BACK_PTRS || PRINT_BLACK_LIST */
/* Object header */
typedef struct {
# if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
/* We potentially keep two different kinds of back */
/* pointers. KEEP_BACK_PTRS stores a single back */
/* pointer in each reachable object to allow reporting */
/* of why an object was retained. MAKE_BACK_GRAPH */
/* builds a graph containing the inverse of all */
/* "points-to" edges including those involving */
/* objects that have just become unreachable. This */
/* allows detection of growing chains of unreachable */
/* objects. It may be possible to eventually combine */
/* both, but for now we keep them separate. Both */
/* kinds of back pointers are hidden using the */
/* following macros. In both cases, the plain version */
/* is constrained to have an least significant bit of 1,*/
/* to allow it to be distinguished from a free list */
/* link. This means the plain version must have an */
/* lsb of 0. */
/* Note that blocks dropped by black-listing will */
/* also have the lsb clear once debugging has */
/* started. */
/* We're careful never to overwrite a value with lsb 0. */
# if ALIGNMENT == 1
/* Fudge back pointer to be even. */
# define HIDE_BACK_PTR(p) HIDE_POINTER(~1 & (GC_word)(p))
# else
# define HIDE_BACK_PTR(p) HIDE_POINTER(p)
# endif
# ifdef KEEP_BACK_PTRS
GC_hidden_pointer oh_back_ptr;
# endif
# ifdef MAKE_BACK_GRAPH
GC_hidden_pointer oh_bg_ptr;
# endif
# if defined(ALIGN_DOUBLE) && \
(defined(KEEP_BACK_PTRS) != defined(MAKE_BACK_GRAPH))
word oh_dummy;
# endif
# endif
GC_CONST char * oh_string; /* object descriptor string */
word oh_int; /* object descriptor integers */
# ifdef NEED_CALLINFO
struct callinfo oh_ci[NFRAMES];
# endif
# ifndef SHORT_DBG_HDRS
word oh_sz; /* Original malloc arg. */
word oh_sf; /* start flag */
# endif /* SHORT_DBG_HDRS */
} oh;
/* The size of the above structure is assumed not to dealign things, */
/* and to be a multiple of the word length. */
#ifdef SHORT_DBG_HDRS
# define DEBUG_BYTES (sizeof (oh))
# define UNCOLLECTABLE_DEBUG_BYTES DEBUG_BYTES
#else
/* Add space for END_FLAG, but use any extra space that was already */
/* added to catch off-the-end pointers. */
/* For uncollectable objects, the extra byte is not added. */
# define UNCOLLECTABLE_DEBUG_BYTES (sizeof (oh) + sizeof (word))
# define DEBUG_BYTES (UNCOLLECTABLE_DEBUG_BYTES - EXTRA_BYTES)
#endif
#define USR_PTR_FROM_BASE(p) ((ptr_t)(p) + sizeof(oh))
/* Round bytes to words without adding extra byte at end. */
#define SIMPLE_ROUNDED_UP_WORDS(n) BYTES_TO_WORDS((n) + WORDS_TO_BYTES(1) - 1)
/* ADD_CALL_CHAIN stores a (partial) call chain into an object */
/* header. It may be called with or without the allocation */
/* lock. */
/* PRINT_CALL_CHAIN prints the call chain stored in an object */
/* to stderr. It requires that we do not hold the lock. */
#ifdef SAVE_CALL_CHAIN
# define ADD_CALL_CHAIN(base, ra) GC_save_callers(((oh *)(base)) -> oh_ci)
# define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci)
#else
# ifdef GC_ADD_CALLER
# define ADD_CALL_CHAIN(base, ra) ((oh *)(base)) -> oh_ci[0].ci_pc = (ra)
# define PRINT_CALL_CHAIN(base) GC_print_callers(((oh *)(base)) -> oh_ci)
# else
# define ADD_CALL_CHAIN(base, ra)
# define PRINT_CALL_CHAIN(base)
# endif
#endif
# ifdef GC_ADD_CALLER
# define OPT_RA ra,
# else
# define OPT_RA
# endif
/* Check whether object with base pointer p has debugging info */
/* p is assumed to point to a legitimate object in our part */
/* of the heap. */
#ifdef SHORT_DBG_HDRS
# define GC_has_other_debug_info(p) TRUE
#else
GC_bool GC_has_other_debug_info(/* p */);
#endif
#if defined(KEEP_BACK_PTRS) || defined(MAKE_BACK_GRAPH)
# define GC_HAS_DEBUG_INFO(p) \
((*((word *)p) & 1) && GC_has_other_debug_info(p))
#else
# define GC_HAS_DEBUG_INFO(p) GC_has_other_debug_info(p)
#endif
/* Store debugging info into p. Return displaced pointer. */
/* Assumes we don't hold allocation lock. */
ptr_t GC_store_debug_info(/* p, sz, string, integer */);
#endif /* _DBG_MLC_H */
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