gcconfig.h

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	/* Note that the backing store base seems to be at a nice 	*/
	/* address minus one page.					*/
#	define BACKING_STORE_DISPLACEMENT 0x1000000
#	define BACKING_STORE_ALIGNMENT 0x1000
#       define BACKING_STORE_BASE \
	  (ptr_t)(((word)GC_stackbottom - BACKING_STORE_DISPLACEMENT - 1) \
			& ~(BACKING_STORE_ALIGNMENT - 1))
#   endif
#   ifdef LINUX
#   	define CPP_WORDSZ 64
#   	define ALIGN_DOUBLE
	  /* Requires 16 byte alignment for malloc */
#   	define ALIGNMENT 8
#       define OS_TYPE "LINUX"
	/* The following works on NUE and older kernels:	*/
/* #       define STACKBOTTOM ((ptr_t) 0xa000000000000000l)	*/
	/* This does not work on NUE:				*/
#       define LINUX_STACKBOTTOM
	/* We also need the base address of the register stack	*/
	/* backing store.  This is computed in 			*/
	/* GC_linux_register_stack_base based on the following	*/
	/* constants:						*/
#       define BACKING_STORE_ALIGNMENT 0x100000
#       define BACKING_STORE_DISPLACEMENT 0x80000000
	extern char * GC_register_stackbottom;
#	define BACKING_STORE_BASE ((ptr_t)GC_register_stackbottom)
#	define SEARCH_FOR_DATA_START
#	define DATASTART GC_data_start
#	ifdef __GNUC__
#         define DYNAMIC_LOADING
#	else
	  /* In the Intel compiler environment, we seem to end up with  */
	  /* statically linked executables and an undefined reference	*/
	  /* to _DYNAMIC						*/
#  	endif
#	define MPROTECT_VDB
		/* Requires Linux 2.3.47 or later.	*/
	extern int _end[];
#	define DATAEND (_end)
#       ifdef __GNUC__
#	  define PREFETCH(x) \
	    __asm__ ("	lfetch	[%0]": : "r"((void *)(x)))
#	  define PREFETCH_FOR_WRITE(x) \
	    __asm__ ("	lfetch.excl	[%0]": : "r"((void *)(x)))
#	  define CLEAR_DOUBLE(x) \
	    __asm__ ("	stf.spill	[%0]=f0": : "r"((void *)(x)))
#       endif
#   endif
# endif

# ifdef M88K
#   define MACH_TYPE "M88K"
#   define ALIGNMENT 4
#   define ALIGN_DOUBLE
    extern int etext[];
#   ifdef CX_UX
#	define OS_TYPE "CX_UX"
#       define DATASTART ((((word)etext + 0x3fffff) & ~0x3fffff) + 0x10000)
#   endif
#   ifdef  DGUX
#	define OS_TYPE "DGUX"
	extern char * GC_SysVGetDataStart();
#       define DATASTART (ptr_t)GC_SysVGetDataStart(0x10000, etext)
#   endif
#   define STACKBOTTOM ((char*)0xf0000000) /* determined empirically */
# endif

# ifdef S370
#   define MACH_TYPE "S370"
#   define ALIGNMENT 4	/* Required by hardware	*/
#   define USE_GENERIC_PUSH_REGS
#   ifdef UTS4
#       define OS_TYPE "UTS4"
        extern int etext[];
	extern int _etext[];
	extern int _end[];
	extern char * GC_SysVGetDataStart();
#       define DATASTART (ptr_t)GC_SysVGetDataStart(0x10000, _etext)
#	define DATAEND (_end)
#	define HEURISTIC2
#   endif
# endif

# ifdef S390
#   define MACH_TYPE "S390"
#   define USE_GENERIC_PUSH_REGS
#   ifndef __s390x__
#	define ALIGNMENT 4
#	define CPP_WORDSZ 32
#   else
#	define ALIGNMENT 8
#	define CPP_WORDSZ 64
#	define HBLKSIZE 4096
#   endif
#   ifdef LINUX
#       define OS_TYPE "LINUX"
#       define LINUX_STACKBOTTOM
#       define DYNAMIC_LOADING
        extern int __data_start[];
#       define DATASTART ((ptr_t)(__data_start))
	extern int _end[];
#	define DATAEND (_end)
#	define CACHE_LINE_SIZE 256
#	define GETPAGESIZE() 4096
#   endif
# endif

# if defined(PJ)
#   define ALIGNMENT 4
    extern int _etext[];
#   define DATASTART ((ptr_t)(_etext))
#   define HEURISTIC1
# endif

# ifdef ARM32
#   define CPP_WORDSZ 32
#   define MACH_TYPE "ARM32"
#   define ALIGNMENT 4
#   ifdef NETBSD
#       define OS_TYPE "NETBSD"
#       define HEURISTIC2
        extern char etext[];
#       define DATASTART ((ptr_t)(etext))
#       define USE_GENERIC_PUSH_REGS
#   endif
#   ifdef LINUX
#       define OS_TYPE "LINUX"
#       define HEURISTIC1
#       undef STACK_GRAN
#       define STACK_GRAN 0x10000000
#       define USE_GENERIC_PUSH_REGS
#       ifdef __ELF__
#            define DYNAMIC_LOADING
#	     include <features.h>
#	     if defined(__GLIBC__) && __GLIBC__ >= 2
#		 define LINUX_DATA_START
#	     else
     	         extern char **__environ;
#                define DATASTART ((ptr_t)(&__environ))
			      /* hideous kludge: __environ is the first */
			      /* word in crt0.o, and delimits the start */
			      /* of the data segment, no matter which   */
			      /* ld options were passed through.        */
			      /* We could use _etext instead, but that  */
			      /* would include .rodata, which may       */
			      /* contain large read-only data tables    */
			      /* that we'd rather not scan.		*/
#	     endif
	     extern int _end[];
#	     define DATAEND (_end)
#	else
	     extern int etext[];
#            define DATASTART ((ptr_t)((((word) (etext)) + 0xfff) & ~0xfff))
#       endif
#   endif
#   ifdef MSWINCE
#     define OS_TYPE "MSWINCE"
#     define DATAEND /* not needed */
#   endif
#   ifdef NOSYS
      /* __data_start is usually defined in the target linker script.  */
      extern int __data_start[];
#     define DATASTART (ptr_t)(__data_start)
#     define USE_GENERIC_PUSH_REGS
      /* __stack_base__ is set in newlib/libc/sys/arm/crt0.S  */
      extern void *__stack_base__;
#     define STACKBOTTOM ((ptr_t) (__stack_base__))
#   endif
#endif

# ifdef SH
#   define MACH_TYPE "SH"
#   define ALIGNMENT 4
#   ifdef MSWINCE
#     define OS_TYPE "MSWINCE"
#     define DATAEND /* not needed */
#   endif
#   ifdef LINUX
#     define OS_TYPE "LINUX"
#     define STACKBOTTOM ((ptr_t) 0x7c000000)
#     define USE_GENERIC_PUSH_REGS
#     define DYNAMIC_LOADING
#     define LINUX_DATA_START
      extern int _end[];
#     define DATAEND (_end)
#   endif
# endif
 
# ifdef SH4
#   define MACH_TYPE "SH4"
#   define OS_TYPE "MSWINCE"
#   define ALIGNMENT 4
#   define DATAEND /* not needed */
# endif

# ifdef X86_64
#   define MACH_TYPE "X86_64"
#   define ALIGNMENT 8
#   define CPP_WORDSZ 64
#   define HBLKSIZE 4096
#   define CACHE_LINE_SIZE 64
#   define USE_GENERIC_PUSH_REGS
#   ifdef LINUX
#	define OS_TYPE "LINUX"
#       define LINUX_STACKBOTTOM
#       if !defined(GC_LINUX_THREADS) || !defined(REDIRECT_MALLOC)
#	    define MPROTECT_VDB
#	else
	    /* We seem to get random errors in incremental mode,	*/
	    /* possibly because Linux threads is itself a malloc client */
	    /* and can't deal with the signals.				*/
#	endif
#       ifdef __ELF__
#            define DYNAMIC_LOADING
#	     ifdef UNDEFINED	/* includes ro data */
	       extern int _etext[];
#              define DATASTART ((ptr_t)((((word) (_etext)) + 0xfff) & ~0xfff))
#	     endif
#	     include <features.h>
#	     define LINUX_DATA_START
	     extern int _end[];
#	     define DATAEND (_end)
#	else
	     extern int etext[];
#            define DATASTART ((ptr_t)((((word) (etext)) + 0xfff) & ~0xfff))
#       endif
#	define PREFETCH(x) \
	  __asm__ __volatile__ ("	prefetch	%0": : "m"(*(char *)(x)))
#	define PREFETCH_FOR_WRITE(x) \
	  __asm__ __volatile__ ("	prefetchw	%0": : "m"(*(char *)(x)))
#   endif
# endif

#ifdef LINUX_DATA_START
    /* Some Linux distributions arrange to define __data_start.  Some	*/
    /* define data_start as a weak symbol.  The latter is technically	*/
    /* broken, since the user program may define data_start, in which	*/
    /* case we lose.  Nonetheless, we try both, prefering __data_start.	*/
    /* We assume gcc.	*/
#   pragma weak __data_start
    extern int __data_start[];
#   pragma weak data_start
    extern int data_start[];
#   define DATASTART ((ptr_t)(__data_start != 0? __data_start : data_start))
#endif

#if defined(LINUX) && defined(REDIRECT_MALLOC)
    /* Rld appears to allocate some memory with its own allocator, and	*/
    /* some through malloc, which might be redirected.  To make this	*/
    /* work with collectable memory, we have to scan memory allocated	*/
    /* by rld's internal malloc.					*/
#   define USE_PROC_FOR_LIBRARIES
#endif
    
# ifndef STACK_GROWS_UP
#   define STACK_GROWS_DOWN
# endif

# ifndef CPP_WORDSZ
#   define CPP_WORDSZ 32
# endif

# ifndef OS_TYPE
#   define OS_TYPE ""
# endif

# ifndef DATAEND
    extern int end[];
#   define DATAEND (end)
# endif

# if defined(SVR4) && !defined(GETPAGESIZE)
#    include <unistd.h>
#    define GETPAGESIZE()  sysconf(_SC_PAGESIZE)
# endif

# ifndef GETPAGESIZE
#   if defined(SUNOS5) || defined(IRIX5)
#	include <unistd.h>
#   endif
#   define GETPAGESIZE() getpagesize()
# endif

# if defined(SUNOS5) || defined(DRSNX) || defined(UTS4)
    /* OS has SVR4 generic features.  Probably others also qualify.	*/
#   define SVR4
# endif

# if defined(SUNOS5) || defined(DRSNX)
    /* OS has SUNOS5 style semi-undocumented interface to dynamic 	*/
    /* loader.								*/
#   define SUNOS5DL
    /* OS has SUNOS5 style signal handlers.				*/
#   define SUNOS5SIGS
# endif

# if defined(HPUX)
#   define SUNOS5SIGS
# endif

# if defined(SVR4) || defined(LINUX) || defined(IRIX) || defined(HPUX) \
    || defined(OPENBSD) || defined(NETBSD) || defined(FREEBSD) \
    || defined(BSD) || defined(_AIX) || defined(MACOSX) || defined(OSF1)
#   define UNIX_LIKE   /* Basic Unix-like system calls work.	*/
# endif

# if CPP_WORDSZ != 32 && CPP_WORDSZ != 64
   -> bad word size
# endif

# ifdef PCR
#   undef DYNAMIC_LOADING
#   undef STACKBOTTOM
#   undef HEURISTIC1
#   undef HEURISTIC2
#   undef PROC_VDB
#   undef MPROTECT_VDB
#   define PCR_VDB
# endif

# ifdef SRC_M3
/* Postponed for now. */
#   undef PROC_VDB
#   undef MPROTECT_VDB
# endif

# ifdef SMALL_CONFIG
/* Presumably not worth the space it takes. */
#   undef PROC_VDB
#   undef MPROTECT_VDB
# endif

# ifdef USE_MUNMAP
#   undef MPROTECT_VDB  /* Can't deal with address space holes. */
# endif

# ifdef PARALLEL_MARK
#   undef MPROTECT_VDB  /* For now.	*/
# endif

# if !defined(PCR_VDB) && !defined(PROC_VDB) && !defined(MPROTECT_VDB)
#   define DEFAULT_VDB
# endif

# ifndef PREFETCH
#   define PREFETCH(x)
#   define NO_PREFETCH
# endif

# ifndef PREFETCH_FOR_WRITE
#   define PREFETCH_FOR_WRITE(x)
#   define NO_PREFETCH_FOR_WRITE
# endif

# ifndef CACHE_LINE_SIZE
#   define CACHE_LINE_SIZE 32	/* Wild guess	*/
# endif

# ifdef LINUX
#   define REGISTER_LIBRARIES_EARLY
    /* We sometimes use dl_iterate_phdr, which may acquire an internal	*/
    /* lock.  This isn't safe after the world has stopped.  So we must	*/
    /* call GC_register_dynamic_libraries before stopping the world.	*/
    /* For performance reasons, this may be beneficial on other		*/
    /* platforms as well, though it should be avoided in win32.		*/
# endif /* LINUX */

# if defined(SEARCH_FOR_DATA_START) && defined(GC_PRIVATE_H)
    extern ptr_t GC_data_start;
# endif

# ifndef CLEAR_DOUBLE
#   define CLEAR_DOUBLE(x) \
	((word*)x)[0] = 0; \
	((word*)x)[1] = 0;
# endif /* CLEAR_DOUBLE */

/* Internally we use GC_SOLARIS_THREADS to test for either old or pthreads. */
# if defined(GC_SOLARIS_PTHREADS) && !defined(GC_SOLARIS_THREADS)
#   define GC_SOLARIS_THREADS
# endif

# if defined(GC_IRIX_THREADS) && !defined(IRIX5)
--> inconsistent configuration
# endif
# if defined(GC_LINUX_THREADS) && !defined(LINUX)
--> inconsistent configuration
# endif
# if defined(GC_SOLARIS_THREADS) && !defined(SUNOS5)
--> inconsistent configuration
# endif
# if defined(GC_HPUX_THREADS) && !defined(HPUX)
--> inconsistent configuration
# endif
# if defined(GC_WIN32_THREADS) && !defined(MSWIN32)
    /* Ideally CYGWIN32 should work, in addition to MSWIN32.  I suspect	*/
    /* the necessary code is mostly there, but nobody has actually made */
    /* sure the right combination of pieces is compiled in, etc.	*/
--> inconsistent configuration
# endif

# if defined(PCR) || defined(SRC_M3) || \
	defined(GC_SOLARIS_THREADS) || defined(GC_WIN32_THREADS) || \
	defined(GC_PTHREADS)
#   define THREADS
# endif

# if defined(HP_PA) || defined(M88K) || defined(POWERPC) && !defined(MACOSX) \
     || defined(LINT) || defined(MSWINCE) \
     || (defined(I386) && defined(__LCC__))
	/* Use setjmp based hack to mark from callee-save registers.    */
	/* The define should move to the individual platform 		*/
	/* descriptions.						*/
#	define USE_GENERIC_PUSH_REGS
# endif

# if defined(SPARC)
#   define ASM_CLEAR_CODE	/* Stack clearing is crucial, and we 	*/
				/* include assembly code to do it well.	*/
# endif

/* Can we save call chain in objects for debugging?   		        */
/* SET NFRAMES (# of saved frames) and NARGS (#of args for each frame)	*/
/* to reasonable values for the platform.				*/
/* Set SAVE_CALL_CHAIN if we can.  SAVE_CALL_COUNT can be specified at	*/
/* build time, though we feel free to adjust it slightly.		*/
/* Define NEED_CALLINFO if we either save the call stack or 		*/
/* GC_ADD_CALLER is defined.						*/
#ifdef LINUX
# include <features.h>
# if __GLIBC__ == 2 && __GLIBC_MINOR__ >= 1 || __GLIBC__ > 2
#   define HAVE_BUILTIN_BACKTRACE
# endif
#endif

#if defined(SPARC)
# define CAN_SAVE_CALL_STACKS
# define CAN_SAVE_CALL_ARGS
#endif
#if (defined(I386) || defined(X86_64)) && defined(LINUX)
    /* SAVE_CALL_CHAIN is supported if the code is compiled to save	*/
    /* frame pointers by default, i.e. no -fomit-frame-pointer flag.	*/
# define CAN_SAVE_CALL_STACKS
# define CAN_SAVE_CALL_ARGS
#endif
#if defined(HAVE_BUILTIN_BACKTRACE) && !defined(CAN_SAVE_CALL_STACKS)
# define CAN_SAVE_CALL_STACKS
#endif

# if defined(SAVE_CALL_COUNT) && !defined(GC_ADD_CALLER) \
     && defined(CAN_SAVE_CALL_STACKS)
#   define SAVE_CALL_CHAIN 
# endif
# ifdef SAVE_CALL_CHAIN
#   if defined(SAVE_CALL_NARGS) && defined(CAN_SAVE_CALL_ARGS)
#     define NARGS SAVE_CALL_NARGS
#   else
#     define NARGS 0	/* Number of arguments to save for each call.	*/
#   endif
# endif
# ifdef SAVE_CALL_CHAIN
#   ifndef SAVE_CALL_COUNT
#     define NFRAMES 6	/* Number of frames to save. Even for		*/
			/* alignment reasons.				*/
#   else
#     define NFRAMES ((SAVE_CALL_COUNT + 1) & ~1)
#   endif
#   define NEED_CALLINFO
# endif /* SAVE_CALL_CHAIN */
# ifdef GC_ADD_CALLER
#   define NFRAMES 1
#   define NARGS 0
#   define NEED_CALLINFO
# endif

# if defined(MAKE_BACK_GRAPH) && !defined(DBG_HDRS_ALL)
#   define DBG_HDRS_ALL
# endif

# endif /* GCCONFIG_H */