path: root/gcc-4.8.1/boehm-gc/include/private/gc_priv.h

/* 
 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
 * Copyright (c) 1991-1994 by Xerox Corporation.  All rights reserved.
 * Copyright (c) 1996-1999 by Silicon Graphics.  All rights reserved.
 * Copyright (c) 1999-2001 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.
 */
 

# ifndef GC_PRIVATE_H
# define GC_PRIVATE_H

/* Autoconf definitions. */
/* FIXME: This should really be included directly from each .c file. */
#include <gc_config.h>

#if defined(mips) && defined(SYSTYPE_BSD) && defined(sony_news)
    /* sony RISC NEWS, NEWSOS 4 */
#   define BSD_TIME
/*    typedef long ptrdiff_t;   -- necessary on some really old systems	*/
#endif

#if defined(mips) && defined(SYSTYPE_BSD43)
    /* MIPS RISCOS 4 */
#   define BSD_TIME
#endif

#ifdef DGUX
#   include <sys/types.h>
#   include <sys/time.h>
#   include <sys/resource.h>
#endif /* DGUX */

#ifdef BSD_TIME
#   include <sys/types.h>
#   include <sys/time.h>
#   include <sys/resource.h>
#endif /* BSD_TIME */

# ifndef _GC_H
#   include "../gc.h"
# endif

# ifndef GC_MARK_H
#   include "../gc_mark.h"
# endif

typedef GC_word word;
typedef GC_signed_word signed_word;

typedef int GC_bool;
# define TRUE 1
# define FALSE 0

typedef char * ptr_t;	/* A generic pointer to which we can add	*/
			/* byte displacements.				*/
			/* Preferably identical to caddr_t, if it 	*/
			/* exists.					*/
			
# ifndef GCCONFIG_H
#   include "gcconfig.h"
# endif

# ifndef HEADERS_H
#   include "gc_hdrs.h"
# endif

#if defined(__STDC__)
#   include <stdlib.h>
#   if !(defined( sony_news ) )
#       include <stddef.h>
#   endif
#   define VOLATILE volatile
#else
#   ifdef MSWIN32
#   	include <stdlib.h>
#   endif
#   define VOLATILE
#endif

#if 0 /* defined(__GNUC__) doesn't work yet */
# define EXPECT(expr, outcome) __builtin_expect(expr,outcome)
  /* Equivalent to (expr), but predict that usually (expr)==outcome. */
#else
# define EXPECT(expr, outcome) (expr)
#endif /* __GNUC__ */

# ifndef GC_LOCKS_H
#   include "gc_locks.h"
# endif

# ifdef STACK_GROWS_DOWN
#   define COOLER_THAN >
#   define HOTTER_THAN <
#   define MAKE_COOLER(x,y) if ((word)(x)+(y) > (word)(x)) {(x) += (y);} \
			    else {(x) = (word)ONES;}
#   define MAKE_HOTTER(x,y) (x) -= (y)
# else
#   define COOLER_THAN <
#   define HOTTER_THAN >
#   define MAKE_COOLER(x,y) if ((word)(x)-(y) < (word)(x)) {(x) -= (y);} else {(x) = 0;}
#   define MAKE_HOTTER(x,y) (x) += (y)
# endif

#if defined(AMIGA) && defined(__SASC)
#   define GC_FAR __far
#else
#   define GC_FAR
#endif


/*********************************/
/*                               */
/* Definitions for conservative  */
/* collector                     */
/*                               */
/*********************************/

/*********************************/
/*                               */
/* Easily changeable parameters  */
/*                               */
/*********************************/

/* #define STUBBORN_ALLOC */
		    /* Enable stubborm allocation, and thus a limited	*/
		    /* form of incremental collection w/o dirty bits.	*/

/* #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.	*/
		    /* This is now really controlled at startup,	*/
		    /* through GC_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      */
		    /* during the reclaim phase.  Typically generates       */
		    /* about one screenful per garbage collection.         */
#undef PRINTBLOCKS

#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

#if defined(PRINTSTATS) || !defined(SMALL_CONFIG)
#   define CONDPRINT  /* Print some things if GC_print_stats is set */
#endif

#define GC_INVOKE_FINALIZERS() GC_notify_or_invoke_finalizers()

#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.						  */

#if defined(USE_MARK_BYTES) && !defined(ALIGN_DOUBLE)
#  define ALIGN_DOUBLE
   /* We use one byte for every 2 words, which doesn't allow for	*/
   /* odd numbered words to have mark bits.				*/
#endif

#if defined(GC_GCJ_SUPPORT) && ALIGNMENT < 8 && !defined(ALIGN_DOUBLE)
   /* GCJ's Hashtable synchronization code requires 64-bit alignment.  */
#  define ALIGN_DOUBLE
#endif

/* ALIGN_DOUBLE requires MERGE_SIZES at present. */
# if defined(ALIGN_DOUBLE) && !defined(MERGE_SIZES)
#   define MERGE_SIZES
# endif

#if !defined(DONT_ADD_BYTE_AT_END)
# define EXTRA_BYTES GC_all_interior_pointers
#else
# define EXTRA_BYTES 0
#endif


# ifndef LARGE_CONFIG
#   define MINHINCR 16	 /* Minimum heap increment, in blocks of HBLKSIZE  */
			 /* Must be multiple of largest page size.	   */
#   define MAXHINCR 2048 /* Maximum heap increment, in blocks              */
# else
#   define MINHINCR 64
#   define MAXHINCR 4096
# endif

# define TIME_LIMIT 50	   /* We try to keep pause times from exceeding	 */
			   /* this by much. In milliseconds.		 */

# define BL_LIMIT GC_black_list_spacing
			   /* If we need a block of N bytes, and we have */
			   /* a block of N + BL_LIMIT bytes available, 	 */
			   /* and N > BL_LIMIT,				 */
			   /* but all possible positions in it are 	 */
			   /* blacklisted, we just use it anyway (and	 */
			   /* print a warning, if warnings are enabled). */
			   /* This risks subsequently leaking the block	 */
			   /* due to a false reference.  But not using	 */
			   /* the block risks unreasonable immediate	 */
			   /* heap growth.				 */

/*********************************/
/*                               */
/* Stack saving for debugging	 */
/*                               */
/*********************************/

#ifdef NEED_CALLINFO
    struct callinfo {
	word ci_pc;  	/* Caller, not callee, pc	*/
#	if NARGS > 0
	    word ci_arg[NARGS];	/* bit-wise complement to avoid retention */
#	endif
#	if defined(ALIGN_DOUBLE) && (NFRAMES * (NARGS + 1)) % 2 == 1
	    /* Likely alignment problem. */
	    word ci_dummy;
#	endif
    };
#endif

#ifdef SAVE_CALL_CHAIN

/* Fill in the pc and argument information for up to NFRAMES of my	*/
/* callers.  Ignore my frame and my callers frame.			*/
void GC_save_callers GC_PROTO((struct callinfo info[NFRAMES]));
  
void GC_print_callers GC_PROTO((struct callinfo info[NFRAMES]));

#endif


/*********************************/
/*                               */
/* OS interface routines	 */
/*                               */
/*********************************/

#ifdef BSD_TIME
#   undef CLOCK_TYPE
#   undef GET_TIME
#   undef MS_TIME_DIFF
#   define CLOCK_TYPE struct timeval
#   define GET_TIME(x) { struct rusage rusage; \
			 getrusage (RUSAGE_SELF,  &rusage); \
			 x = rusage.ru_utime; }
#   define MS_TIME_DIFF(a,b) ((double) (a.tv_sec - b.tv_sec) * 1000.0 \
                               + (double) (a.tv_usec - b.tv_usec) / 1000.0)
#else /* !BSD_TIME */
# if defined(MSWIN32) || defined(MSWINCE)
#   include <windows.h>
#   include <winbase.h>
#   define CLOCK_TYPE DWORD
#   define GET_TIME(x) x = GetTickCount()
#   define MS_TIME_DIFF(a,b) ((long)((a)-(b)))
# else /* !MSWIN32, !MSWINCE, !BSD_TIME */
#   include <time.h>
#   if !defined(__STDC__) && defined(SPARC) && defined(SUNOS4)
      clock_t clock();	/* Not in time.h, where it belongs	*/
#   endif
#   if defined(FREEBSD) && !defined(CLOCKS_PER_SEC)
#     include <machine/limits.h>
#     define CLOCKS_PER_SEC CLK_TCK
#   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 these 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))
# endif /* !MSWIN32 */
#endif /* !BSD_TIME */

/* We use bzero and bcopy internally.  They may not be available.	*/
# if defined(SPARC) && defined(SUNOS4)
#   define BCOPY_EXISTS
# endif
# if defined(M68K) && defined(AMIGA)
#   define BCOPY_EXISTS
# endif
# if defined(M68K) && defined(NEXT)
#   define BCOPY_EXISTS
# endif
# if defined(VAX)
#   define BCOPY_EXISTS
# endif
# if defined(AMIGA)
#   include <string.h>
#   define BCOPY_EXISTS
# endif
# if defined(DARWIN)
#   include <string.h>
#   define BCOPY_EXISTS
# endif

# ifndef BCOPY_EXISTS
#   include <string.h>
#   define BCOPY(x,y,n) memcpy(y, x, (size_t)(n))
#   define BZERO(x,n)  memset(x, 0, (size_t)(n))
# else
#   define BCOPY(x,y,n) bcopy((char *)(x),(char *)(y),(int)(n))
#   define BZERO(x,n) bzero((char *)(x),(int)(n))
# 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.							*/
/* It probably doesn't make any sense to declare these to be nonempty	*/
/* if the code is being optimized, since signal safety relies on some	*/
/* ordering constraints that are typically not obeyed by optimizing	*/
/* compilers.								*/
# 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 defined(THREADS) || defined(AMIGA)  \
	|| defined(MSWIN32) || defined(MSWINCE) || defined(MACOS) \
	|| defined(DJGPP) || defined(NO_SIGNALS) 
			/* Also useful for debugging.		*/
	/* Should probably use thr_sigsetmask for GC_SOLARIS_THREADS. */
#     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
#   if defined(GC_SOLARIS_THREADS) || defined(GC_WIN32_THREADS) \
	|| defined(GC_PTHREADS)
      void GC_stop_world();
      void GC_start_world();
#     define STOP_WORLD() GC_stop_world()
#     define START_WORLD() GC_start_world()
#   else
#     define STOP_WORLD()
#     define START_WORLD()
#   endif
# endif

/* Abandon ship */
# ifdef PCR
#   define ABORT(s) PCR_Base_Panic(s)
# else
#   ifdef SMALL_CONFIG
#	define ABORT(msg) abort();
#   else
	GC_API void GC_abort GC_PROTO((GC_CONST char * msg));
#       define ABORT(msg) GC_abort(msg);
#   endif
# endif

/* Exit abnormally, but without making a mess (e.g. out of memory) */
# ifdef PCR
#   define EXIT() PCR_Base_Exit(1,PCR_waitForever)
# else
#   define EXIT() (void)exit(1)
# endif

/* Print warning message, e.g. almost out of memory.	*/
# define WARN(msg,arg) (*GC_current_warn_proc)("GC Warning: " msg, (GC_word)(arg))
extern GC_warn_proc GC_current_warn_proc;

/* Get environment entry */
#if !defined(NO_GETENV)
#   if defined(EMPTY_GETENV_RESULTS)
	/* Workaround for a reputed Wine bug.	*/
	static inline char * fixed_getenv(const char *name)
	{
	  char * tmp = getenv(name);
	  if (tmp == 0 || strlen(tmp) == 0)
	    return 0;
	  return tmp;
	}
#       define GETENV(name) fixed_getenv(name)
#   else
#       define GETENV(name) getenv(name)
#   endif
#else
#   define GETENV(name) 0
#endif

#if defined(DARWIN)
#      if defined(POWERPC)
#              if CPP_WORDSZ == 32
#                define GC_THREAD_STATE_T ppc_thread_state_t
#		 define GC_MACH_THREAD_STATE PPC_THREAD_STATE
#		 define GC_MACH_THREAD_STATE_COUNT PPC_THREAD_STATE_COUNT
#                define GC_MACH_HEADER mach_header
#                define GC_MACH_SECTION section
#                define GC_GETSECTBYNAME getsectbynamefromheader
#              else
#                define GC_THREAD_STATE_T ppc_thread_state64_t
#		 define GC_MACH_THREAD_STATE PPC_THREAD_STATE64
#		 define GC_MACH_THREAD_STATE_COUNT PPC_THREAD_STATE64_COUNT
#                define GC_MACH_HEADER mach_header_64
#                define GC_MACH_SECTION section_64
#                define GC_GETSECTBYNAME getsectbynamefromheader_64
#              endif
#      elif defined(I386) || defined(X86_64)
#              if CPP_WORDSZ == 32
#                define GC_THREAD_STATE_T x86_thread_state32_t
#                define GC_MACH_THREAD_STATE x86_THREAD_STATE32
#                define GC_MACH_THREAD_STATE_COUNT x86_THREAD_STATE32_COUNT
#                define GC_MACH_HEADER mach_header
#                define GC_MACH_SECTION section
#                define GC_GETSECTBYNAME getsectbynamefromheader
#              else
#                define GC_THREAD_STATE_T x86_thread_state64_t
#                define GC_MACH_THREAD_STATE x86_THREAD_STATE64
#                define GC_MACH_THREAD_STATE_COUNT x86_THREAD_STATE64_COUNT
#                define GC_MACH_HEADER mach_header_64
#                define GC_MACH_SECTION section_64
#                define GC_GETSECTBYNAME getsectbynamefromheader_64
#              endif
#      else
#              error define GC_THREAD_STATE_T
#              define GC_MACH_THREAD_STATE MACHINE_THREAD_STATE
#              define GC_MACH_THREAD_STATE_COUNT MACHINE_THREAD_STATE_COUNT
#      endif
/* Try to work out the right way to access thread state structure members.
   The structure has changed its definition in different Darwin versions.
   This now defaults to the (older) names without __, thus hopefully,
   not breaking any existing Makefile.direct builds.  */
#      if defined (HAS_PPC_THREAD_STATE___R0) \
	 || defined (HAS_PPC_THREAD_STATE64___R0) \
	 || defined (HAS_X86_THREAD_STATE32___EAX) \
	 || defined (HAS_X86_THREAD_STATE64___RAX)
#        define THREAD_FLD(x) __ ## x
#      else
#        define THREAD_FLD(x) x
#      endif
#endif
/*********************************/
/*                               */
/* 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	    */
#  if ALIGNMENT != 4
#	define UNALIGNED
#  endif
#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	    */
#  if ALIGNMENT != 8
#	define UNALIGNED
#  endif
#endif

#define WORDSZ ((word)CPP_WORDSZ)
#define SIGNB  ((word)1 << (WORDSZ-1))
#define BYTES_PER_WORD      ((word)(sizeof (word)))
#define ONES                ((word)(signed_word)(-1))
#define divWORDSZ(n) ((n) >> LOGWL)	   /* divide n by size of word      */

/*********************/
/*                   */
/*  Size Parameters  */
/*                   */
/*********************/

/*  heap block size, bytes. Should be power of 2 */

#ifndef HBLKSIZE
# ifdef SMALL_CONFIG
#   define CPP_LOG_HBLKSIZE 10
# else
#   if (CPP_WORDSZ == 32) || (defined(HPUX) && defined(HP_PA))
      /* HPUX/PA seems to use 4K pages with the 64 bit ABI */
#     define CPP_LOG_HBLKSIZE 12
#   else
#     define CPP_LOG_HBLKSIZE 13
#   endif
# endif
#else
# if HBLKSIZE == 512
#   define CPP_LOG_HBLKSIZE 9
# endif
# if HBLKSIZE == 1024
#   define CPP_LOG_HBLKSIZE 10
# endif
# if HBLKSIZE == 2048
#   define CPP_LOG_HBLKSIZE 11
# endif
# if HBLKSIZE == 4096
#   define CPP_LOG_HBLKSIZE 12
# endif
# if HBLKSIZE == 8192
#   define CPP_LOG_HBLKSIZE 13
# endif
# if HBLKSIZE == 16384
#   define CPP_LOG_HBLKSIZE 14
# endif
# ifndef CPP_LOG_HBLKSIZE
    --> fix HBLKSIZE
# endif
# undef HBLKSIZE
#endif
# define CPP_HBLKSIZE (1 << CPP_LOG_HBLKSIZE)
# define LOG_HBLKSIZE   ((word)CPP_LOG_HBLKSIZE)
# define HBLKSIZE ((word)CPP_HBLKSIZE)


/*  max size objects supported by freelist (larger objects may be   */
/*  allocated, but less efficiently)                                */

#define CPP_MAXOBJBYTES (CPP_HBLKSIZE/2)
#define MAXOBJBYTES ((word)CPP_MAXOBJBYTES)
#define CPP_MAXOBJSZ    BYTES_TO_WORDS(CPP_MAXOBJBYTES)
#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, etc. */
# define ROUNDED_UP_WORDS(n) \
	BYTES_TO_WORDS((n) + (WORDS_TO_BYTES(1) - 1 + EXTRA_BYTES))
# ifdef ALIGN_DOUBLE
#       define ALIGNED_WORDS(n) \
	    (BYTES_TO_WORDS((n) + WORDS_TO_BYTES(2) - 1 + EXTRA_BYTES) & ~1)
# else
#       define ALIGNED_WORDS(n) ROUNDED_UP_WORDS(n)
# endif
# define SMALL_OBJ(bytes) ((bytes) <= (MAXOBJBYTES - EXTRA_BYTES))
# define ADD_SLOP(bytes) ((bytes) + EXTRA_BYTES)
# ifndef MIN_WORDS
    /* MIN_WORDS is the size of the smallest allocated object.	*/
    /* 1 and 2 are the only valid values.			*/
    /* 2 must be used if:					*/
    /* - GC_gcj_malloc can be used for objects of requested 	*/
    /*   size  smaller than 2 words, or				*/
    /* - USE_MARK_BYTES is defined.				*/
#   if defined(USE_MARK_BYTES) || defined(GC_GCJ_SUPPORT)
#     define MIN_WORDS 2   	/* Smallest allocated object.	*/
#   else
#     define MIN_WORDS 1
#   endif
# 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.
 */
 
# ifdef LARGE_CONFIG
#   define LOG_PHT_ENTRIES  20  /* Collisions likely at 1M blocks,	*/
				/* which is >= 4GB.  Each table takes	*/
				/* 128KB, some of which may never be	*/
				/* touched.				*/
# else
#   ifdef SMALL_CONFIG
#     define LOG_PHT_ENTRIES  14 /* Collisions are likely if heap grows	*/
				 /* to more than 16K hblks = 64MB.	*/
				 /* Each hash table occupies 2K bytes.   */
#   else /* default "medium" configuration */
#     define LOG_PHT_ENTRIES  16 /* Collisions are likely if heap grows	*/
				 /* to more than 64K hblks >= 256MB.	*/
				 /* Each hash table occupies 8K bytes.  */
				 /* Even for somewhat smaller heaps, 	*/
				 /* say half that, collisions may be an	*/
				 /* issue because we blacklist 		*/
				 /* addresses outside the heap.		*/
#   endif
# endif
# 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))
/* And a dumb but thread-safe version of set_pht_entry_from_index.	*/
/* This sets (many) extra bits.						*/
# define set_pht_entry_from_index_safe(bl, index) \
		(bl)[divWORDSZ(index)] = ONES
	


/********************************************/
/*                                          */
/*    H e a p   B l o c k s                 */
/*                                          */
/********************************************/

/*  heap block header */
#define HBLKMASK   (HBLKSIZE-1)

#define BITS_PER_HBLK (CPP_HBLKSIZE * 8)

#define MARK_BITS_PER_HBLK (BITS_PER_HBLK/CPP_WORDSZ)
	   /* upper bound                                    */
	   /* We allocate 1 bit/word, unless USE_MARK_BYTES  */
	   /* is defined.  Only the first word   	     */
	   /* in each object is actually marked.             */

# ifdef USE_MARK_BYTES
#   define MARK_BITS_SZ (MARK_BITS_PER_HBLK/2)
	/* Unlike the other case, this is in units of bytes.		*/
	/* We actually allocate only every second mark bit, since we	*/
	/* force all objects to be doubleword aligned.			*/
	/* However, each mark bit is allocated as a byte.		*/
# else
#   define MARK_BITS_SZ (MARK_BITS_PER_HBLK/CPP_WORDSZ)
# endif

/* We maintain layout maps for heap blocks containing objects of a given */
/* size.  Each entry in this map describes a byte offset and has the	 */
/* following type.							 */
typedef unsigned char map_entry_type;

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.				 */
    struct hblk * hb_prev;	/* Backwards link for free list.	*/
    word hb_descr;   		/* object descriptor for marking.  See	*/
    				/* mark.h.				*/
    map_entry_type * 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 char 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 char hb_flags;
#	define IGNORE_OFF_PAGE	1	/* Ignore pointers that do not	*/
					/* point to the first page of 	*/
					/* this object.			*/
#	define WAS_UNMAPPED 2	/* This is a free block, which has	*/
				/* been unmapped from the address 	*/
				/* space.				*/
				/* GC_remap must be invoked on it	*/
				/* before it can be reallocated.	*/
				/* Only set with USE_MUNMAP.		*/
    unsigned short hb_last_reclaimed;
    				/* Value of GC_gc_no when block was	*/
    				/* last allocated or swept. May wrap.   */
				/* For a free block, this is maintained */
				/* only for USE_MUNMAP, and indicates	*/
				/* when the header was allocated, or	*/
				/* when the size of the block last	*/
				/* changed.				*/
#   ifdef USE_MARK_BYTES
      union {
        char _hb_marks[MARK_BITS_SZ];
			    /* The i'th byte is 1 if the object 	*/
			    /* starting at word 2i is marked, 0 o.w.	*/
	word dummy;	/* Force word alignment of mark bytes. */
      } _mark_byte_union;
#     define hb_marks _mark_byte_union._hb_marks
#   else
      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.		    */
			    /* Unused bits are invalid, and are 	    */
			    /* occasionally set, e.g for uncollectable	    */
			    /* objects.					    */
#   endif /* !USE_MARK_BYTES */
};

/*  heap block body */

# define BODY_SZ (HBLKSIZE/sizeof(word))

struct hblk {
    word hb_body[BODY_SZ];
};

# define HBLK_IS_FREE(hdr) ((hdr) -> hb_map == GC_invalid_map)

# define OBJ_SZ_TO_BLOCKS(sz) \
    divHBLKSZ(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))

# define LOG_MAX_MARK_PROCS 6
# define MAX_MARK_PROCS (1 << LOG_MAX_MARK_PROCS)

/* Root sets.  Logically private to mark_rts.c.  But we don't want the	*/
/* tables scanned, so we put them here.					*/
/* MAX_ROOT_SETS is the maximum number of ranges that can be 	*/
/* registered as static roots. 					*/
# ifdef LARGE_CONFIG
#   define MAX_ROOT_SETS 4096
# else
    /* GCJ LOCAL: MAX_ROOT_SETS increased to permit more shared */
    /* libraries to be loaded.                                  */ 
#   define MAX_ROOT_SETS 1024
# endif

# define MAX_EXCLUSIONS (MAX_ROOT_SETS/4)
/* Maximum number of segments that can be excluded from root sets.	*/

/*
 * Data structure for excluded static roots.
 */
struct exclusion {
    ptr_t e_start;
    ptr_t e_end;
};

/* Data structure for list of root sets.				*/
/* We keep a hash table, so that we can filter out duplicate additions.	*/
/* Under Win32, we need to do a better job of filtering overlaps, so	*/
/* we resort to sequential search, and pay the price.			*/
struct roots {
	ptr_t r_start;
	ptr_t r_end;
#	if !defined(MSWIN32) && !defined(MSWINCE) && !defined(CYGWIN32)
	  struct roots * r_next;
#	endif
	GC_bool r_tmp;
	  	/* Delete before registering new dynamic libraries */
};

#if !defined(MSWIN32) && !defined(MSWINCE) && !defined(CYGWIN32)
    /* Size of hash table index to roots.	*/
#   define LOG_RT_SIZE 6
#   define RT_SIZE (1 << LOG_RT_SIZE) /* Power of 2, may be != MAX_ROOT_SETS */
#endif

/* Lists of all heap blocks and free lists	*/
/* as well as other random data structures	*/
/* that should not be scanned by the		*/
/* collector.					*/
/* 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.		*/
/* The main fields should precede any 		*/
/* conditionally included fields, so that	*/
/* gc_inl.h will work even if a different set	*/
/* of macros is defined when the client is	*/
/* compiled.					*/

struct _GC_arrays {
  word _heapsize;
  word _max_heapsize;
  word _requested_heapsize;	/* Heap size due to explicit expansion */
  ptr_t _last_heap_addr;
  ptr_t _prev_heap_addr;
  word _large_free_bytes;
	/* Total bytes contained in blocks on large object free */
	/* list.						*/
  word _large_allocd_bytes;
  	/* Total number of bytes in allocated large objects blocks.	*/
  	/* For the purposes of this counter and the next one only, a 	*/
  	/* large object is one that occupies a block of at least	*/
  	/* 2*HBLKSIZE.							*/
  word _max_large_allocd_bytes;
  	/* Maximum number of bytes that were ever allocated in		*/
  	/* large object blocks.  This is used to help decide when it	*/
  	/* is safe to split up a large block.				*/
  word _words_allocd_before_gc;
		/* Number of words allocated before this	*/
		/* collection cycle.				*/
# ifndef SEPARATE_GLOBALS
    word _words_allocd;
  	/* Number of words allocated during this collection cycle */
# endif
  word _words_wasted;
  	/* Number of words wasted due to internal fragmentation	*/
  	/* in large objects, or due to dropping blacklisted     */
	/* blocks, since last gc.  Approximate.                 */
  word _words_finalized;
  	/* Approximate number of words in objects (and headers)	*/
  	/* That became ready for finalization in the last 	*/
  	/* collection.						*/
  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.				*/
  word _finalizer_mem_freed;
  	/* Words of memory explicitly deallocated while 	*/
  	/* finalizers were running.  Used to approximate mem.	*/
  	/* explicitly deallocated by finalizers.		*/
  ptr_t _scratch_end_ptr;
  ptr_t _scratch_last_end_ptr;
	/* Used by headers.c, and can easily appear to point to	*/
	/* heap.						*/
  GC_mark_proc _mark_procs[MAX_MARK_PROCS];
  	/* Table of user-defined mark procedures.  There is	*/
	/* a small number of these, which can be referenced	*/
	/* by DS_PROC mark descriptors.  See gc_mark.h.		*/

# ifndef SEPARATE_GLOBALS
    ptr_t _objfreelist[MAXOBJSZ+1];
			  /* free list for objects */
    ptr_t _aobjfreelist[MAXOBJSZ+1];
			  /* free list for atomic objs 	*/
# endif

  ptr_t _uobjfreelist[MAXOBJSZ+1];
			  /* uncollectable but traced objs 	*/
			  /* objects on this and auobjfreelist  */
			  /* are always marked, except during   */
			  /* garbage collections.		*/
# ifdef ATOMIC_UNCOLLECTABLE
    ptr_t _auobjfreelist[MAXOBJSZ+1];
# endif
			  /* uncollectable but traced objs 	*/

# 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
# ifdef USE_MUNMAP
    word _unmapped_bytes;
# endif
# ifdef MERGE_SIZES
    unsigned _size_map[WORDS_TO_BYTES(MAXOBJSZ+1)];
    	/* Number of words to allocate for a given allocation request in */
    	/* bytes.							 */
# endif 

# ifdef STUBBORN_ALLOC
    ptr_t _sobjfreelist[MAXOBJSZ+1];
# endif
  			  /* free list for immutable objects	*/
  map_entry_type * _obj_map[MAXOBJSZ+1];
                       /* If not NIL, then a pointer to a map of valid  */
    		       /* object addresses. _obj_map[sz][i] is j if the	*/
    		       /* address block_start+i is a valid pointer      */
    		       /* to an object at block_start +			*/
 		       /* WORDS_TO_BYTES(BYTES_TO_WORDS(i) - j)		*/
  		       /* I.e. j is a word displacement from the	*/
  		       /* object beginning.				*/
  		       /* The entry is OBJ_INVALID if the corresponding	*/
  		       /* address is not a valid pointer.  It is 	*/
  		       /* OFFSET_TOO_BIG if the value j would be too 	*/
  		       /* large to fit in the entry.  (Note that the	*/
  		       /* size of these entries matters, both for 	*/
  		       /* space consumption and for cache utilization.)	*/
#   define OFFSET_TOO_BIG 0xfe
#   define OBJ_INVALID 0xff
#   define MAP_ENTRY(map, bytes) (map)[bytes]
#   define MAP_ENTRIES HBLKSIZE
#   define MAP_SIZE MAP_ENTRIES
#   define CPP_MAX_OFFSET (OFFSET_TOO_BIG - 1)	
#   define MAX_OFFSET ((word)CPP_MAX_OFFSET)
    /* The following are used only if GC_all_interior_ptrs != 0 */
# 	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.	*/
  	char _modws_valid_offsets[sizeof(word)];
				/* GC_valid_offsets[i] ==>		  */
				/* GC_modws_valid_offsets[i%sizeof(word)] */
#   define OFFSET_VALID(displ) \
	  (GC_all_interior_pointers || GC_valid_offsets[displ])
# ifdef STUBBORN_ALLOC
    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
# ifdef MPROTECT_VDB
    VOLATILE page_hash_table _dirty_pages;	
			/* Pages dirtied since last GC_read_dirty. */
# endif
# ifdef PROC_VDB
    page_hash_table _written_pages;	/* Pages ever dirtied	*/
# endif
# ifdef LARGE_CONFIG
#   if CPP_WORDSZ > 32
#     define MAX_HEAP_SECTS 4096 	/* overflows at roughly 64 GB	   */
#   else
#     define MAX_HEAP_SECTS 768		/* Separately added heap sections. */
#   endif
# else
#   ifdef SMALL_CONFIG
#     define MAX_HEAP_SECTS 128		/* Roughly 256MB (128*2048*1K)	*/
#   else
#     define MAX_HEAP_SECTS 384		/* Roughly 3GB			*/
#   endif
# endif
  struct HeapSect {
      ptr_t hs_start; word hs_bytes;
  } _heap_sects[MAX_HEAP_SECTS];
# if defined(MSWIN32) || defined(MSWINCE) || defined(CYGWIN32)
    ptr_t _heap_bases[MAX_HEAP_SECTS];
    		/* Start address of memory regions obtained from kernel. */
# endif
# ifdef MSWINCE
    word _heap_lengths[MAX_HEAP_SECTS];
    		/* Commited lengths of memory regions obtained from kernel. */
# endif
  struct roots _static_roots[MAX_ROOT_SETS];
# if !defined(MSWIN32) && !defined(MSWINCE) && !defined(CYGWIN32)
    struct roots * _root_index[RT_SIZE];
# endif
  struct exclusion _excl_table[MAX_EXCLUSIONS];
  /* Block header index; see gc_headers.h */
  bottom_index * _all_nils;
  bottom_index * _top_index [TOP_SZ];
#ifdef SAVE_CALL_CHAIN
  struct callinfo _last_stack[NFRAMES];	/* Stack at last garbage collection.*/
  					/* Useful for debugging	mysterious  */
  					/* object disappearances.	    */
  					/* In the multithreaded case, we    */
  					/* currently only save the calling  */
  					/* stack.			    */
#endif
};

GC_API GC_FAR struct _GC_arrays GC_arrays; 

# ifndef SEPARATE_GLOBALS
#   define GC_objfreelist GC_arrays._objfreelist
#   define GC_aobjfreelist GC_arrays._aobjfreelist
#   define GC_words_allocd GC_arrays._words_allocd
# endif
# define GC_uobjfreelist GC_arrays._uobjfreelist
# ifdef ATOMIC_UNCOLLECTABLE
#   define GC_auobjfreelist GC_arrays._auobjfreelist
# endif
# define GC_sobjfreelist GC_arrays._sobjfreelist
# define GC_valid_offsets GC_arrays._valid_offsets
# define GC_modws_valid_offsets GC_arrays._modws_valid_offsets
# ifdef STUBBORN_ALLOC
#    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_wasted GC_arrays._words_wasted
# define GC_large_free_bytes GC_arrays._large_free_bytes
# define GC_large_allocd_bytes GC_arrays._large_allocd_bytes
# define GC_max_large_allocd_bytes GC_arrays._max_large_allocd_bytes
# define GC_words_finalized GC_arrays._words_finalized
# define GC_non_gc_bytes_at_gc GC_arrays._non_gc_bytes_at_gc
# define GC_mem_freed GC_arrays._mem_freed
# define GC_finalizer_mem_freed GC_arrays._finalizer_mem_freed
# define GC_scratch_end_ptr GC_arrays._scratch_end_ptr
# define GC_scratch_last_end_ptr GC_arrays._scratch_last_end_ptr
# define GC_mark_procs GC_arrays._mark_procs
# define GC_heapsize GC_arrays._heapsize
# define GC_max_heapsize GC_arrays._max_heapsize
# define GC_requested_heapsize GC_arrays._requested_heapsize
# define GC_words_allocd_before_gc GC_arrays._words_allocd_before_gc
# define GC_heap_sects GC_arrays._heap_sects
# define GC_last_stack GC_arrays._last_stack
# ifdef USE_MUNMAP
#   define GC_unmapped_bytes GC_arrays._unmapped_bytes
# endif
# if defined(MSWIN32) || defined(MSWINCE) || defined (CYGWIN32)
#   define GC_heap_bases GC_arrays._heap_bases
# endif
# ifdef MSWINCE
#   define GC_heap_lengths GC_arrays._heap_lengths
# endif
# define GC_static_roots GC_arrays._static_roots
# define GC_root_index GC_arrays._root_index
# define GC_excl_table GC_arrays._excl_table
# 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 MPROTECT_VDB
#   define GC_dirty_pages GC_arrays._dirty_pages
# endif
# ifdef PROC_VDB
#   define GC_written_pages GC_arrays._written_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 USED_HEAP_SIZE (GC_heapsize - GC_large_free_bytes)

/* Object kinds: */
# define MAXOBJKINDS 16

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.					  */
   word ok_descriptor;  /* Descriptor template for objects in this	*/
   			/* block.					*/
   GC_bool ok_relocate_descr;
   			/* Add object size in bytes to descriptor 	*/
   			/* template to obtain descriptor.  Otherwise	*/
   			/* template is used as is.			*/
   GC_bool ok_init;   /* Clear objects before putting them on the free list. */
} GC_obj_kinds[MAXOBJKINDS];

# define beginGC_obj_kinds ((ptr_t)(&GC_obj_kinds))
# define endGC_obj_kinds (beginGC_obj_kinds + (sizeof GC_obj_kinds))

/* Variables that used to be in GC_arrays, but need to be accessed by 	*/
/* inline allocation code.  If they were in GC_arrays, the inlined 	*/
/* allocation code would include GC_arrays offsets (as it did), which	*/
/* introduce maintenance problems.					*/

#ifdef SEPARATE_GLOBALS
  word GC_words_allocd;
  	/* Number of words allocated during this collection cycle */
  ptr_t GC_objfreelist[MAXOBJSZ+1];
			  /* free list for NORMAL objects */
# define beginGC_objfreelist ((ptr_t)(&GC_objfreelist))
# define endGC_objfreelist (beginGC_objfreelist + sizeof(GC_objfreelist))

  ptr_t GC_aobjfreelist[MAXOBJSZ+1];
			  /* free list for atomic (PTRFREE) objs 	*/
# define beginGC_aobjfreelist ((ptr_t)(&GC_aobjfreelist))
# define endGC_aobjfreelist (beginGC_aobjfreelist + sizeof(GC_aobjfreelist))
#endif

/* Predefined kinds: */
# define PTRFREE 0
# define NORMAL  1
# define UNCOLLECTABLE 2
# ifdef ATOMIC_UNCOLLECTABLE
#   define AUNCOLLECTABLE 3
#   define STUBBORN 4
#   define IS_UNCOLLECTABLE(k) (((k) & ~1) == UNCOLLECTABLE)
# else
#   define STUBBORN 3
#   define IS_UNCOLLECTABLE(k) ((k) == UNCOLLECTABLE)
# endif

extern int GC_n_kinds;

GC_API word GC_fo_entries;

extern word GC_n_heap_sects;	/* Number of separately added heap	*/
				/* sections.				*/

extern word GC_page_size;

# if defined(MSWIN32) || defined(MSWINCE) || defined(CYGWIN32)
  struct _SYSTEM_INFO;
  extern struct _SYSTEM_INFO GC_sysinfo;
  extern word GC_n_heap_bases;	/* See GC_heap_bases.	*/
# endif

extern word GC_total_stack_black_listed;
			/* Number of bytes on stack blacklist. 	*/

extern word GC_black_list_spacing;
			/* Average number of bytes between blacklisted	*/
			/* blocks. Approximate.				*/
			/* Counts only blocks that are 			*/
			/* "stack-blacklisted", i.e. that are 		*/
			/* problematic in the interior of an object.	*/

extern map_entry_type * 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 GC_bool GC_objects_are_marked;	/* There are marked objects in  */
					/* the heap.			*/

#ifndef SMALL_CONFIG
  extern GC_bool GC_incremental;
			/* Using incremental/generational collection. */
# define TRUE_INCREMENTAL \
	(GC_incremental && GC_time_limit != GC_TIME_UNLIMITED)
	/* True incremental, not just generational, mode */
#else
# define GC_incremental FALSE
			/* Hopefully allow optimizer to remove some code. */
# define TRUE_INCREMENTAL FALSE
#endif

extern GC_bool GC_dirty_maintained;
				/* Dirty bits are being maintained, 	*/
				/* either for incremental collection,	*/
				/* or to limit the root set.		*/

extern word GC_root_size;	/* Total size of registered root sections */

extern GC_bool GC_debugging_started;	/* GC_debug_malloc has been called. */ 

extern long GC_large_alloc_warn_interval;
	/* Interval between unsuppressed warnings.	*/

extern long GC_large_alloc_warn_suppressed;
	/* Number of warnings suppressed so far.	*/

#ifdef THREADS
  extern GC_bool GC_world_stopped;
#endif

/* Operations */
# 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.                                         */

/* Set mark bit correctly, even if mark bits may be concurrently 	*/
/* accessed.								*/
#ifdef PARALLEL_MARK
# define OR_WORD(addr, bits) \
	{ word old; \
	  do { \
	    old = *((volatile word *)addr); \
	  } while (!GC_compare_and_exchange((addr), old, old | (bits))); \
	}
# define OR_WORD_EXIT_IF_SET(addr, bits, exit_label) \
	{ word old; \
	  word my_bits = (bits); \
	  do { \
	    old = *((volatile word *)addr); \
	    if (old & my_bits) goto exit_label; \
	  } while (!GC_compare_and_exchange((addr), old, old | my_bits)); \
	}
#else
# define OR_WORD(addr, bits) *(addr) |= (bits)
# define OR_WORD_EXIT_IF_SET(addr, bits, exit_label) \
	{ \
	  word old = *(addr); \
	  word my_bits = (bits); \
	  if (old & my_bits) goto exit_label; \
	  *(addr) = (old | my_bits); \
	}
#endif

/* Mark bit operations */

/*
 * 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)
 */

#ifdef USE_MARK_BYTES
# define mark_bit_from_hdr(hhdr,n) ((hhdr)->hb_marks[(n) >> 1])
# define set_mark_bit_from_hdr(hhdr,n) ((hhdr)->hb_marks[(n)>>1]) = 1
# define clear_mark_bit_from_hdr(hhdr,n) ((hhdr)->hb_marks[(n)>>1]) = 0
#else /* !USE_MARK_BYTES */
# define mark_bit_from_hdr(hhdr,n) (((hhdr)->hb_marks[divWORDSZ(n)] \
			    >> (modWORDSZ(n))) & (word)1)
# define set_mark_bit_from_hdr(hhdr,n) \
			    OR_WORD((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))
#endif /* !USE_MARK_BYTES */

/* Important internal collector routines */

ptr_t GC_approx_sp GC_PROTO((void));
  
GC_bool GC_should_collect GC_PROTO((void));
  
void GC_apply_to_all_blocks GC_PROTO(( \
    void (*fn) GC_PROTO((struct hblk *h, word client_data)), \
    word client_data));
  			/* Invoke fn(hbp, client_data) for each 	*/
  			/* allocated heap block.			*/
struct hblk * GC_next_used_block GC_PROTO((struct hblk * h));
  			/* Return first in-use block >= h	*/
struct hblk * GC_prev_block GC_PROTO((struct hblk * h));
  			/* Return last block <= h.  Returned block	*/
  			/* is managed by GC, but may or may not be in	*/
			/* use.						*/
void GC_mark_init GC_PROTO((void));
void GC_clear_marks GC_PROTO((void));	/* Clear mark bits for all heap objects. */
void GC_invalidate_mark_state GC_PROTO((void));
					/* Tell the marker that	marked 	   */
  					/* objects may point to	unmarked   */
  					/* ones, and roots may point to	   */
  					/* unmarked objects.		   */
  					/* Reset mark stack.		   */
GC_bool GC_mark_stack_empty GC_PROTO((void));
GC_bool GC_mark_some GC_PROTO((ptr_t cold_gc_frame));
  			/* 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_gc GC_PROTO((void));
				/* initiate collection.			*/
  				/* If the mark state is invalid, this	*/
  				/* becomes full colleection.  Otherwise */
  				/* it's partial.			*/
void GC_push_all GC_PROTO((ptr_t bottom, ptr_t top));
				/* Push everything in a range 		*/
  				/* onto mark stack.			*/
void GC_push_selected GC_PROTO(( \
    ptr_t bottom, \
    ptr_t top, \
    int (*dirty_fn) GC_PROTO((struct hblk *h)), \
    void (*push_fn) GC_PROTO((ptr_t bottom, ptr_t top)) ));
				  /* Push all pages h in [b,t) s.t. 	*/
				  /* select_fn(h) != 0 onto mark stack. */
#ifndef SMALL_CONFIG
  void GC_push_conditional GC_PROTO((ptr_t b, ptr_t t, GC_bool all));
#else
# define GC_push_conditional(b, t, all) GC_push_all(b, t)
#endif
                                /* Do either of the above, depending	*/
				/* on the third arg.			*/
void GC_push_all_stack GC_PROTO((ptr_t b, ptr_t t));
				    /* As above, but consider		*/
				    /*  interior pointers as valid  	*/
void GC_push_all_eager GC_PROTO((ptr_t b, ptr_t t));
				    /* Same as GC_push_all_stack, but   */
				    /* ensures that stack is scanned	*/
				    /* immediately, not just scheduled  */
				    /* for scanning.			*/
#ifndef THREADS
  void GC_push_all_stack_partially_eager GC_PROTO(( \
      ptr_t bottom, ptr_t top, ptr_t cold_gc_frame ));
			/* Similar to GC_push_all_eager, but only the	*/
			/* part hotter than cold_gc_frame is scanned	*/
			/* immediately.  Needed to ensure that callee-	*/
			/* save registers are not missed.		*/
#else
  /* In the threads case, we push part of the current thread stack	*/
  /* with GC_push_all_eager when we push the registers.  This gets the  */
  /* callee-save registers that may disappear.  The remainder of the	*/
  /* stacks are scheduled for scanning in *GC_push_other_roots, which	*/
  /* is thread-package-specific.					*/
#endif
void GC_push_current_stack GC_PROTO((ptr_t cold_gc_frame));
  			/* Push enough of the current stack eagerly to	*/
  			/* ensure that callee-save registers saved in	*/
  			/* GC frames are scanned.			*/
  			/* In the non-threads case, schedule entire	*/
  			/* stack for scanning.				*/
void GC_push_roots GC_PROTO((GC_bool all, ptr_t cold_gc_frame));
  			/* Push all or dirty roots.	*/
extern void (*GC_push_other_roots) GC_PROTO((void));
  			/* Push system or application specific roots	*/
  			/* onto the mark stack.  In some environments	*/
  			/* (e.g. threads environments) this is		*/
  			/* predfined to be non-zero.  A client supplied */
  			/* replacement should also call the original	*/
  			/* function.					*/
extern void GC_push_gc_structures GC_PROTO((void));
			/* Push GC internal roots.  These are normally	*/
			/* included in the static data segment, and 	*/
			/* Thus implicitly pushed.  But we must do this	*/
			/* explicitly if normal root processing is 	*/
			/* disabled.  Calls the following:		*/
	extern void GC_push_finalizer_structures GC_PROTO((void));
	extern void GC_push_stubborn_structures GC_PROTO((void));
#	ifdef THREADS
	  extern void GC_push_thread_structures GC_PROTO((void));
#	endif
extern void (*GC_start_call_back) GC_PROTO((void));
  			/* Called at start of full collections.		*/
  			/* Not called if 0.  Called with allocation 	*/
  			/* lock held.					*/
  			/* 0 by default.				*/
# if defined(USE_GENERIC_PUSH_REGS)
  void GC_generic_push_regs GC_PROTO((ptr_t cold_gc_frame));
# else
  void GC_push_regs GC_PROTO((void));
# endif
# if defined(SPARC) || defined(IA64)
  /* Cause all stacked registers to be saved in memory.  Return a	*/
  /* pointer to the top of the corresponding memory stack.		*/
  word GC_save_regs_in_stack GC_PROTO((void));
# endif
			/* Push register contents onto mark stack.	*/
  			/* If NURSERY is defined, the default push	*/
  			/* action can be overridden with GC_push_proc	*/

# ifdef NURSERY
    extern void (*GC_push_proc)(ptr_t);
# endif
# if defined(MSWIN32) || defined(MSWINCE)
  void __cdecl GC_push_one GC_PROTO((word p));
# else
  void GC_push_one GC_PROTO((word p));
			      /* If p points to an object, mark it    */
                              /* and push contents on the mark stack  */
  			      /* Pointer recognition test always      */
  			      /* accepts interior pointers, i.e. this */
  			      /* is appropriate for pointers found on */
  			      /* stack.				      */
# endif
# if defined(PRINT_BLACK_LIST) || defined(KEEP_BACK_PTRS)
  void GC_mark_and_push_stack GC_PROTO((word p, ptr_t source));
				/* Ditto, omits plausibility test	*/
# else
  void GC_mark_and_push_stack GC_PROTO((word p));
# endif
void GC_push_marked GC_PROTO((struct hblk * h, hdr * hhdr));
		/* Push contents of all marked objects in h onto	*/
		/* mark stack.						*/
#ifdef SMALL_CONFIG
# define GC_push_next_marked_dirty(h) GC_push_next_marked(h)
#else
  struct hblk * GC_push_next_marked_dirty GC_PROTO((struct hblk * h));
		/* Invoke GC_push_marked on next dirty block above h.	*/
		/* Return a pointer just past the end of this block.	*/
#endif /* !SMALL_CONFIG */
struct hblk * GC_push_next_marked GC_PROTO((struct hblk * h));
  		/* Ditto, but also mark from clean pages.	*/
struct hblk * GC_push_next_marked_uncollectable GC_PROTO((struct hblk * h));
  		/* Ditto, but mark only from uncollectable pages.	*/
GC_bool GC_stopped_mark GC_PROTO((GC_stop_func stop_func));
 			/* Stop world and mark from all roots	*/
  			/* and rescuers.			*/
void GC_clear_hdr_marks GC_PROTO((hdr * hhdr));
				    /* Clear the mark bits in a header */
void GC_set_hdr_marks GC_PROTO((hdr * hhdr));
 				    /* Set the mark bits in a header */
void GC_set_fl_marks GC_PROTO((ptr_t p));
				    /* Set all mark bits associated with */
				    /* a free list.			 */
void GC_add_roots_inner GC_PROTO((char * b, char * e, GC_bool tmp));
void GC_remove_roots_inner GC_PROTO((char * b, char * e));
GC_bool GC_is_static_root GC_PROTO((ptr_t p));
  		/* Is the address p in one of the registered static	*/
  		/* root sections?					*/
# if defined(MSWIN32) || defined(_WIN32_WCE_EMULATION) || defined(CYGWIN32)
GC_bool GC_is_tmp_root GC_PROTO((ptr_t p));
		/* Is the address p in one of the temporary static	*/
		/* root sections?					*/
# endif
void GC_register_dynamic_libraries GC_PROTO((void));
  		/* Add dynamic library data sections to the root set. */

GC_bool GC_register_main_static_data GC_PROTO((void));
		/* We need to register the main data segment.  Returns	*/
		/* TRUE unless this is done implicitly as part of	*/
		/* dynamic library registration.			*/
  
/* Machine dependent startup routines */
ptr_t GC_get_stack_base GC_PROTO((void));	/* Cold end of stack */
#ifdef IA64
  ptr_t GC_get_register_stack_base GC_PROTO((void));
  					/* Cold end of register stack.	*/
#endif
void GC_register_data_segments GC_PROTO((void));
  
/* Black listing: */
void GC_bl_init GC_PROTO((void));
# ifdef PRINT_BLACK_LIST
      void GC_add_to_black_list_normal GC_PROTO((word p, ptr_t source));
			/* Register bits as a possible future false	*/
			/* reference from the heap or static data	*/
#     define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \
      		if (GC_all_interior_pointers) { \
		  GC_add_to_black_list_stack(bits, (ptr_t)(source)); \
		} else { \
  		  GC_add_to_black_list_normal(bits, (ptr_t)(source)); \
		}
# else
      void GC_add_to_black_list_normal GC_PROTO((word p));
#     define GC_ADD_TO_BLACK_LIST_NORMAL(bits, source) \
      		if (GC_all_interior_pointers) { \
		  GC_add_to_black_list_stack(bits); \
		} else { \
  		  GC_add_to_black_list_normal(bits); \
		}
# endif

# ifdef PRINT_BLACK_LIST
    void GC_add_to_black_list_stack GC_PROTO((word p, ptr_t source));
# else
    void GC_add_to_black_list_stack GC_PROTO((word p));
# endif
struct hblk * GC_is_black_listed GC_PROTO((struct hblk * h, word 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 GC_PROTO((void));
  			/* Declare an end to a black listing phase.	*/
void GC_unpromote_black_lists GC_PROTO((void));
  			/* Approximately undo the effect of the above.	*/
  			/* This actually loses some information, but	*/
  			/* only in a reasonably safe way.		*/
word GC_number_stack_black_listed GC_PROTO(( \
	struct hblk *start, struct hblk *endp1));
  			/* Return the number of (stack) blacklisted	*/
  			/* blocks in the range for statistical		*/
  			/* purposes.					*/
  		 	
ptr_t GC_scratch_alloc GC_PROTO((word bytes));
  				/* GC internal memory allocation for	*/
  				/* small objects.  Deallocation is not  */
  				/* possible.				*/
  	
/* Heap block layout maps: */			
void GC_invalidate_map GC_PROTO((hdr * hhdr));
  				/* Remove the object map associated	*/
  				/* with the block.  This identifies	*/
  				/* the block as invalid to the mark	*/
  				/* routines.				*/
GC_bool GC_add_map_entry GC_PROTO((word sz));
  				/* Add a heap block map for objects of	*/
  				/* size sz to obj_map.			*/
  				/* Return FALSE on failure.		*/
void GC_register_displacement_inner GC_PROTO((word offset));
  				/* Version of GC_register_displacement	*/
  				/* that assumes lock is already held	*/
  				/* and signals are already disabled.	*/
  
/*  hblk allocation: */		
void GC_new_hblk GC_PROTO((word size_in_words, int kind));
  				/* Allocate a new heap block, and build */
  				/* a free list in it.			*/				

ptr_t GC_build_fl GC_PROTO((struct hblk *h, word sz,
			   GC_bool clear,  ptr_t list));
				/* Build a free list for objects of 	*/
				/* size sz in block h.  Append list to	*/
				/* end of the free lists.  Possibly	*/
				/* clear objects on the list.  Normally	*/
				/* called by GC_new_hblk, but also	*/
				/* called explicitly without GC lock.	*/

struct hblk * GC_allochblk GC_PROTO(( \
	word size_in_words, int kind, unsigned flags));
				/* Allocate a heap block, inform	*/
				/* the marker that block is valid	*/
				/* for objects of indicated size.	*/

ptr_t GC_alloc_large GC_PROTO((word lw, int k, unsigned flags));
			/* Allocate a large block of size lw words.	*/
			/* The block is not cleared.			*/
			/* Flags is 0 or IGNORE_OFF_PAGE.		*/
			/* Calls GC_allchblk to do the actual 		*/
			/* allocation, but also triggers GC and/or	*/
			/* heap expansion as appropriate.		*/
			/* Does not update GC_words_allocd, but does	*/
			/* other accounting.				*/

ptr_t GC_alloc_large_and_clear GC_PROTO((word lw, int k, unsigned flags));
			/* As above, but clear block if appropriate	*/
			/* for kind k.					*/

void GC_freehblk GC_PROTO((struct hblk * p));
				/* Deallocate a heap block and mark it  */
  				/* as invalid.				*/
  				
/*  Misc GC: */
void GC_init_inner GC_PROTO((void));
GC_bool GC_expand_hp_inner GC_PROTO((word n));
void GC_start_reclaim GC_PROTO((int 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 GC_PROTO((word sz, int 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 GC_PROTO((void));
  				/* Arrange for all reclaim lists to be	*/
  				/* empty.  Judiciously choose between	*/
  				/* sweeping and discarding each page.	*/
GC_bool GC_reclaim_all GC_PROTO((GC_stop_func stop_func, GC_bool ignore_old));
  				/* Reclaim all blocks.  Abort (in a	*/
  				/* consistent state) if f returns TRUE. */
GC_bool GC_block_empty GC_PROTO((hdr * hhdr));
 				/* Block completely unmarked? 	*/
GC_bool GC_never_stop_func GC_PROTO((void));
				/* Returns FALSE.		*/
GC_bool GC_try_to_collect_inner GC_PROTO((GC_stop_func f));

				/* Collect; caller must have acquired	*/
				/* lock and disabled signals.		*/
				/* Collection is aborted if f returns	*/
				/* TRUE.  Returns TRUE if it completes	*/
				/* successfully.			*/
# define GC_gcollect_inner() \
	(void) GC_try_to_collect_inner(GC_never_stop_func)
void GC_finish_collection GC_PROTO((void));
 				/* Finish collection.  Mark bits are	*/
  				/* consistent and lock is still held.	*/
GC_bool GC_collect_or_expand GC_PROTO(( \
	word needed_blocks, GC_bool ignore_off_page));
  				/* Collect or expand heap in an attempt */
  				/* make the indicated number of free	*/
  				/* blocks available.  Should be called	*/
  				/* until the blocks are available or	*/
  				/* until it fails by returning FALSE.	*/

extern GC_bool GC_is_initialized;	/* GC_init() has been run.	*/

#if defined(MSWIN32) || defined(MSWINCE)
  void GC_deinit GC_PROTO((void));
                                /* Free any resources allocated by      */
                                /* GC_init                              */
#endif

void GC_collect_a_little_inner GC_PROTO((int 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 GC_PROTO((word lb, int k)); */
  				/* Allocate an object of the given	*/
  				/* kind.  By default, there are only	*/
  				/* a few kinds: composite(pointerfree), */
				/* atomic, uncollectable, etc.		*/
				/* 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.			*/
				/* The actual decl is in gc_mark.h.	*/
ptr_t GC_generic_malloc_ignore_off_page GC_PROTO((size_t b, int k));
  				/* As above, but pointers past the 	*/
  				/* first page of the resulting object	*/
  				/* are ignored.				*/
ptr_t GC_generic_malloc_inner GC_PROTO((word lb, int k));
  				/* Ditto, but I already hold lock, etc.	*/
ptr_t GC_generic_malloc_words_small_inner GC_PROTO((word lw, int k));
				/* Analogous to the above, but assumes	*/
				/* a small object size, and bypasses	*/
				/* MERGE_SIZES mechanism.		*/
ptr_t GC_generic_malloc_words_small GC_PROTO((size_t lw, int k));
  				/* As above, but size in units of words */
  				/* Bypasses MERGE_SIZES.  Assumes	*/
  				/* words <= MAXOBJSZ.			*/
ptr_t GC_generic_malloc_inner_ignore_off_page GC_PROTO((size_t lb, int k));
  				/* Allocate an object, where		*/
  				/* the client guarantees that there	*/
  				/* will always be a pointer to the 	*/
  				/* beginning of the object while the	*/
  				/* object is live.			*/
ptr_t GC_allocobj GC_PROTO((word sz, int kind));
  				/* Make the indicated 			*/
  				/* free list nonempty, and return its	*/
  				/* head.				*/

void GC_free_inner(GC_PTR p);
  
void GC_init_headers GC_PROTO((void));
struct hblkhdr * GC_install_header GC_PROTO((struct hblk *h));
  				/* Install a header for block h.	*/
  				/* Return 0 on failure, or the header	*/
  				/* otherwise.				*/
GC_bool GC_install_counts GC_PROTO((struct hblk * h, word sz));
  				/* Set up forwarding counts for block	*/
  				/* h of size sz.			*/
  				/* Return FALSE on failure.		*/
void GC_remove_header GC_PROTO((struct hblk * h));
  				/* Remove the header for block h.	*/
void GC_remove_counts GC_PROTO((struct hblk * h, word sz));
  				/* Remove forwarding counts for h.	*/
hdr * GC_find_header GC_PROTO((ptr_t h)); /* Debugging only.		*/
  
void GC_finalize GC_PROTO((void));
 			/* Perform all indicated finalization actions	*/
  			/* on unmarked objects.				*/
  			/* Unreachable finalizable objects are enqueued	*/
  			/* for processing by GC_invoke_finalizers.	*/
  			/* Invoked with lock.				*/

void GC_notify_or_invoke_finalizers GC_PROTO((void));
			/* If GC_finalize_on_demand is not set, invoke	*/
			/* eligible finalizers. Otherwise:		*/
			/* Call *GC_finalizer_notifier if there are	*/
			/* finalizers to be run, and we haven't called	*/
			/* this procedure yet this GC cycle.		*/

GC_API GC_PTR GC_make_closure GC_PROTO((GC_finalization_proc fn, GC_PTR data));
GC_API void GC_debug_invoke_finalizer GC_PROTO((GC_PTR obj, GC_PTR data));
			/* Auxiliary fns to make finalization work	*/
			/* correctly with displaced pointers introduced	*/
			/* by the debugging allocators.			*/
  			
void GC_add_to_heap GC_PROTO((struct hblk *p, word bytes));
  			/* Add a HBLKSIZE aligned chunk to the heap.	*/
  
void GC_print_obj GC_PROTO((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) GC_PROTO((void));
  			/* Check that all objects in the heap with 	*/
  			/* debugging info are intact.  			*/
  			/* Add any that are not to GC_smashed list.	*/
extern void (*GC_print_all_smashed) GC_PROTO((void));
			/* Print GC_smashed if it's not empty.		*/
			/* Clear GC_smashed list.			*/
extern void GC_print_all_errors GC_PROTO((void));
			/* Print smashed and leaked objects, if any.	*/
			/* Clear the lists of such objects.		*/
extern void (*GC_print_heap_obj) GC_PROTO((ptr_t p));
  			/* If possible print s followed by a more	*/
  			/* detailed description of the object 		*/
  			/* referred to by p.				*/
#if defined(LINUX) && defined(__ELF__) && !defined(SMALL_CONFIG)
  void GC_print_address_map GC_PROTO((void));
  			/* Print an address map of the process.		*/
#endif

extern GC_bool GC_have_errors;  /* We saw a smashed or leaked object.	*/
				/* Call error printing routine 		*/
				/* occasionally.			*/
extern GC_bool GC_print_stats;	/* Produce at least some logging output	*/
				/* Set from environment variable.	*/

#ifndef NO_DEBUGGING
  extern GC_bool GC_dump_regularly;  /* Generate regular debugging dumps. */
# define COND_DUMP if (GC_dump_regularly) GC_dump();
#else
# define COND_DUMP
#endif

#ifdef KEEP_BACK_PTRS
  extern long GC_backtraces;
  void GC_generate_random_backtrace_no_gc(void);
#endif

extern GC_bool GC_print_back_height;

#ifdef MAKE_BACK_GRAPH
  void GC_print_back_graph_stats(void);
#endif

/* Macros used for collector internal allocation.	*/
/* These assume the collector lock is held.		*/
#ifdef DBG_HDRS_ALL
    extern GC_PTR GC_debug_generic_malloc_inner(size_t lb, int k);
    extern GC_PTR GC_debug_generic_malloc_inner_ignore_off_page(size_t lb,
								int k);
#   define GC_INTERNAL_MALLOC GC_debug_generic_malloc_inner
#   define GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE \
		 GC_debug_generic_malloc_inner_ignore_off_page
#   ifdef THREADS
#       define GC_INTERNAL_FREE GC_debug_free_inner
#   else
#       define GC_INTERNAL_FREE GC_debug_free
#   endif
#else
#   define GC_INTERNAL_MALLOC GC_generic_malloc_inner
#   define GC_INTERNAL_MALLOC_IGNORE_OFF_PAGE \
		 GC_generic_malloc_inner_ignore_off_page
#   ifdef THREADS
#       define GC_INTERNAL_FREE GC_free_inner
#   else
#       define GC_INTERNAL_FREE GC_free
#   endif
#endif

/* Memory unmapping: */
#ifdef USE_MUNMAP
  void GC_unmap_old(void);
  void GC_merge_unmapped(void);
  void GC_unmap(ptr_t start, word bytes);
  void GC_remap(ptr_t start, word bytes);
  void GC_unmap_gap(ptr_t start1, word bytes1, ptr_t start2, word bytes2);
#endif

/* Virtual dirty bit implementation:		*/
/* Each implementation exports the following:	*/
void GC_read_dirty GC_PROTO((void));
			/* Retrieve dirty bits.	*/
GC_bool GC_page_was_dirty GC_PROTO((struct hblk *h));
  			/* Read retrieved dirty bits.	*/
GC_bool GC_page_was_ever_dirty GC_PROTO((struct hblk *h));
  			/* Could the page contain valid heap pointers?	*/
void GC_is_fresh GC_PROTO((struct hblk *h, word n));
  			/* Assert the region currently contains no	*/
  			/* valid pointers.				*/
void GC_remove_protection GC_PROTO((struct hblk *h, word nblocks,
			   	    GC_bool pointerfree));
  			/* h is about to be writteni or allocated.  Ensure  */
			/* that it's not write protected by the virtual	    */
			/* dirty bit implementation.			    */
			
void GC_dirty_init GC_PROTO((void));
  
/* Slow/general mark bit manipulation: */
GC_API GC_bool GC_is_marked GC_PROTO((ptr_t p));
void GC_clear_mark_bit GC_PROTO((ptr_t p));
void GC_set_mark_bit GC_PROTO((ptr_t p));
  
/* Stubborn objects: */
void GC_read_changed GC_PROTO((void));	/* Analogous to GC_read_dirty */
GC_bool GC_page_was_changed GC_PROTO((struct hblk * h));
 				/* Analogous to GC_page_was_dirty */
void GC_clean_changing_list GC_PROTO((void));
 				/* Collect obsolete changing list entries */
void GC_stubborn_init GC_PROTO((void));
  
/* Debugging print routines: */
void GC_print_block_list GC_PROTO((void));
void GC_print_hblkfreelist GC_PROTO((void));
void GC_print_heap_sects GC_PROTO((void));
void GC_print_static_roots GC_PROTO((void));
void GC_print_finalization_stats GC_PROTO((void));
void GC_dump GC_PROTO((void));

#ifdef KEEP_BACK_PTRS
   void GC_store_back_pointer(ptr_t source, ptr_t dest);
   void GC_marked_for_finalization(ptr_t dest);
#  define GC_STORE_BACK_PTR(source, dest) GC_store_back_pointer(source, dest)
#  define GC_MARKED_FOR_FINALIZATION(dest) GC_marked_for_finalization(dest)
#else
#  define GC_STORE_BACK_PTR(source, dest) 
#  define GC_MARKED_FOR_FINALIZATION(dest)
#endif

/* Make arguments appear live to compiler */
# ifdef __WATCOMC__
    void GC_noop(void*, ...);
# else
#   ifdef __DMC__
      GC_API void GC_noop(...);
#   else
      GC_API void GC_noop();
#   endif
# endif

void GC_noop1 GC_PROTO((word));

/* Logging and diagnostic output: 	*/
GC_API void GC_printf GC_PROTO((GC_CONST char * format, long, long, long, long, long, long));
			/* 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)

GC_API void GC_err_printf GC_PROTO((GC_CONST char * format, long, long, long, long, long, long));
# 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 GC_PROTO((GC_CONST char *s));
			/* Write s to stderr, don't buffer, don't add	*/
			/* newlines, don't ...				*/

#if defined(LINUX) && !defined(SMALL_CONFIG)
  void GC_err_write GC_PROTO((GC_CONST char *buf, size_t len));
 			/* Write buf to stderr, don't buffer, don't add	*/
  			/* newlines, don't ...				*/
#endif


# ifdef GC_ASSERTIONS
#	define GC_ASSERT(expr) if(!(expr)) {\
		GC_err_printf2("Assertion failure: %s:%ld\n", \
				__FILE__, (unsigned long)__LINE__); \
		ABORT("assertion failure"); }
# else 
#	define GC_ASSERT(expr)
# endif

/* Check a compile time assertion at compile time.  The error	*/
/* message for failure is a bit baroque, but ...		*/
#if defined(mips) && !defined(__GNUC__)
/* DOB: MIPSPro C gets an internal error taking the sizeof an array type. 
   This code works correctly (ugliness is to avoid "unused var" warnings) */
# define GC_STATIC_ASSERT(expr) do { if (0) { char j[(expr)? 1 : -1]; j[0]='\0'; j[0]=j[0]; } } while(0)
#else
# define GC_STATIC_ASSERT(expr) sizeof(char[(expr)? 1 : -1])
#endif

# if defined(PARALLEL_MARK) || defined(THREAD_LOCAL_ALLOC)
    /* We need additional synchronization facilities from the thread	*/
    /* support.  We believe these are less performance critical		*/
    /* than the main garbage collector lock; standard pthreads-based	*/
    /* implementations should be sufficient.				*/

    /* The mark lock and condition variable.  If the GC lock is also 	*/
    /* acquired, the GC lock must be acquired first.  The mark lock is	*/
    /* used to both protect some variables used by the parallel		*/
    /* marker, and to protect GC_fl_builder_count, below.		*/
    /* GC_notify_all_marker() is called when				*/ 
    /* the state of the parallel marker changes				*/
    /* in some significant way (see gc_mark.h for details).  The	*/
    /* latter set of events includes incrementing GC_mark_no.		*/
    /* GC_notify_all_builder() is called when GC_fl_builder_count	*/
    /* reaches 0.							*/

     extern void GC_acquire_mark_lock();
     extern void GC_release_mark_lock();
     extern void GC_notify_all_builder();
     /* extern void GC_wait_builder(); */
     extern void GC_wait_for_reclaim();

     extern word GC_fl_builder_count;	/* Protected by mark lock.	*/
# endif /* PARALLEL_MARK || THREAD_LOCAL_ALLOC */
# ifdef PARALLEL_MARK
     extern void GC_notify_all_marker();
     extern void GC_wait_marker();
     extern word GC_mark_no;		/* Protected by mark lock.	*/

     extern void GC_help_marker(word my_mark_no);
		/* Try to help out parallel marker for mark cycle 	*/
		/* my_mark_no.  Returns if the mark cycle finishes or	*/
		/* was already done, or there was nothing to do for	*/
		/* some other reason.					*/
# endif /* PARALLEL_MARK */

# if defined(GC_PTHREADS) && !defined(GC_SOLARIS_THREADS)
  /* We define the thread suspension signal here, so that we can refer	*/
  /* to it in the dirty bit implementation, if necessary.  Ideally we	*/
  /* would allocate a (real-time ?) signal using the standard mechanism.*/
  /* unfortunately, there is no standard mechanism.  (There is one 	*/
  /* in Linux glibc, but it's not exported.)  Thus we continue to use	*/
  /* the same hard-coded signals we've always used.			*/
#  if !defined(SIG_SUSPEND)
#   if defined(GC_LINUX_THREADS) || defined(GC_DGUX386_THREADS)
#    if defined(SPARC) && !defined(SIGPWR)
       /* SPARC/Linux doesn't properly define SIGPWR in <signal.h>.
        * It is aliased to SIGLOST in asm/signal.h, though.		*/
#      define SIG_SUSPEND SIGLOST
#    else
       /* Linuxthreads itself uses SIGUSR1 and SIGUSR2.			*/
#      define SIG_SUSPEND SIGPWR
#    endif
#   else  /* !GC_LINUX_THREADS */
#     if defined(_SIGRTMIN)
#       define SIG_SUSPEND _SIGRTMIN + 6
#     else
#       define SIG_SUSPEND SIGRTMIN + 6
#     endif       
#   endif
#  endif /* !SIG_SUSPEND */
  
# endif

# endif /* GC_PRIVATE_H */