libgcc2.c

早期freebsd实现

  asm ("	sw	$4,0($30)");
  asm ("	sw	$5,4($30)");
  asm ("	sw	$6,8($30)");
  asm ("	sw	$7,12($30)");
  asm ("	j	$31");
  asm ("	.end __builtin_saveregs");
#else /* not __mips__, etc. */
__builtin_saveregs ()
{
  abort ();
}
#endif /* not __mips__ */
#endif /* not __sparc__ */
#endif /* not __i860__ */
#endif

#ifdef L_eprintf
#ifndef inhibit_eprintf

#undef NULL /* Avoid errors if stdio.h and our stddef.h mismatch.  */
#include <stdio.h>
/* This is used by the `assert' macro.  */
void
__eprintf (string, expression, line, filename)
     const char *string;
     const char *expression;
     int line;
     const char *filename;
{
  fprintf (stderr, string, expression, line, filename);
  fflush (stderr);
  abort ();
}

#endif
#endif

#ifdef L_bb
/* Avoid warning from ranlib about empty object file.  */
void
__bb_avoid_warning ()
{}

#if defined (__sun__) && defined (__mc68000__)
struct bb
{
  int initialized;
  char *filename;
  int *counts;
  int ncounts;
  int zero_word;
  int *addresses;
};

extern int ___tcov_init;

__bb_init_func (blocks)
	struct bb *blocks;
{
  if (! ___tcov_init)
    ___tcov_init_func ();

  ___bb_link (blocks->filename, blocks->counts, blocks->ncounts);
}

#endif
#endif

/* frills for C++ */

#ifdef L_builtin_new

#include <sys/types.h>

typedef void (*vfp)(void);

extern vfp __new_handler;

void *
__builtin_new (sz)
     size_t sz;
{
  void *p;

  /* malloc (0) is unpredictable; avoid it.  */
  if (sz == 0)
    sz = 1;
  p = (void *) malloc (sz);
  if (p == 0)
    (*__new_handler) ();
  return p;
}
#endif

#ifdef L_caps_New

/* This gets us __GNU_LIBRARY__.  */
#undef NULL /* Avoid errors if stdio.h and our stddef.h mismatch.  */
#include <stdio.h>
#include <sys/types.h>

#ifdef __GNU_LIBRARY__
  /* Avoid forcing the library's meaning of `write' on the user program
     by using the "internal" name (for use within the library)  */
#define write(fd, buf, n)	__write((fd), (buf), (n))
#endif

typedef void (*vfp)(void);

extern void *__builtin_new (size_t);
static void default_new_handler (void);

vfp __new_handler = default_new_handler;


void *
__builtin_vec_new (p, maxindex, size, ctor)
     void *p;
     size_t maxindex;
     size_t size;
     void (*ctor)(void *);
{
  size_t i;
  size_t nelts = maxindex + 1;
  void *rval;

  if (p == 0)
    p = __builtin_new (nelts * size);

  rval = p;

  for (i = 0; i < nelts; i++)
    {
      (*ctor) (p);
      p += size;
    }

  return rval;
}

vfp
__set_new_handler (handler)
     vfp handler;
{
  vfp prev_handler;

  prev_handler = __new_handler;
  if (handler == 0) handler = default_new_handler;
  __new_handler = handler;
  return prev_handler;
}

vfp
set_new_handler (handler)
     vfp handler;
{
  return __set_new_handler (handler);
}

#define MESSAGE "Virtual memory exceeded in `new'\n"

static void
default_new_handler ()
{
  /* don't use fprintf (stderr, ...) because it may need to call malloc.  */
  /* This should really print the name of the program, but that is hard to
     do.  We need a standard, clean way to get at the name.  */
  write (2, MESSAGE, sizeof (MESSAGE));
  /* don't call exit () because that may call global destructors which
     may cause a loop.  */
  _exit (-1);
}
#endif

#ifdef L_builtin_del

#include <sys/types.h>

typedef void (*vfp)(void);

void
__builtin_delete (ptr)
     void *ptr;
{
  if (ptr)
    free (ptr);
}

void
__builtin_vec_delete (ptr, maxindex, size, dtor, auto_delete_vec, auto_delete)
     void *ptr;
     size_t maxindex;
     size_t size;
     void (*dtor)(void *, int);
     int auto_delete;
{
  size_t i;
  size_t nelts = maxindex + 1;
  void *p = ptr;

  ptr += nelts * size;

  for (i = 0; i < nelts; i++)
    {
      ptr -= size;
      (*dtor) (ptr, auto_delete);
    }

  if (auto_delete_vec)
    __builtin_delete (p);
}

#endif

#ifdef L_shtab
unsigned int __shtab[] = {
    0x00000001, 0x00000002, 0x00000004, 0x00000008,
    0x00000010, 0x00000020, 0x00000040, 0x00000080,
    0x00000100, 0x00000200, 0x00000400, 0x00000800,
    0x00001000, 0x00002000, 0x00004000, 0x00008000,
    0x00010000, 0x00020000, 0x00040000, 0x00080000,
    0x00100000, 0x00200000, 0x00400000, 0x00800000,
    0x01000000, 0x02000000, 0x04000000, 0x08000000,
    0x10000000, 0x20000000, 0x40000000, 0x80000000
  };
#endif

#ifdef L_clear_cache
/* Clear part of an instruction cache.  */

#define INSN_CACHE_PLANE_SIZE (INSN_CACHE_SIZE / INSN_CACHE_DEPTH)

void
__clear_cache (beg, end)
     char *beg, *end;
{
#ifdef INSN_CACHE_SIZE
  static char array[INSN_CACHE_SIZE + INSN_CACHE_PLANE_SIZE + INSN_CACHE_LINE_WIDTH];
  static int initialized = 0;
  int offset;
  void *start_addr
  void *end_addr;
  typedef (*function_ptr) ();

#if (INSN_CACHE_SIZE / INSN_CACHE_LINE_WIDTH) < 16
  /* It's cheaper to clear the whole cache.
     Put in a series of jump instructions so that calling the beginning
     of the cache will clear the whole thing.  */

  if (! initialized)
    {
      int ptr = (((int) array + INSN_CACHE_LINE_WIDTH - 1)
		 & -INSN_CACHE_LINE_WIDTH);
      int end_ptr = ptr + INSN_CACHE_SIZE;

      while (ptr < end_ptr)
	{
	  *(INSTRUCTION_TYPE *)ptr
	    = JUMP_AHEAD_INSTRUCTION + INSN_CACHE_LINE_WIDTH;
	  ptr += INSN_CACHE_LINE_WIDTH;
	}
      *(INSTRUCTION_TYPE *)(ptr - INSN_CACHE_LINE_WIDTH) = RETURN_INSTRUCTION;

      initialized = 1;
    }

  /* Call the beginning of the sequence.  */
  (((function_ptr) (((int) array + INSN_CACHE_LINE_WIDTH - 1)
		    & -INSN_CACHE_LINE_WIDTH))
   ());

#else /* Cache is large.  */

  if (! initialized)
    {
      int ptr = (((int) array + INSN_CACHE_LINE_WIDTH - 1)
		 & -INSN_CACHE_LINE_WIDTH);

      while (ptr < (int) array + sizeof array)
	{
	  *(INSTRUCTION_TYPE *)ptr = RETURN_INSTRUCTION;
	  ptr += INSN_CACHE_LINE_WIDTH;
	}

      initialized = 1;
    }

  /* Find the location in array that occupies the same cache line as BEG.  */

  offset = ((int) beg & -INSN_CACHE_LINE_WIDTH) & (INSN_CACHE_PLANE_SIZE - 1);
  start_addr = (((int) (array + INSN_CACHE_PLANE_SIZE - 1)
		 & -INSN_CACHE_PLANE_SIZE)
		+ offset);

  /* Compute the cache alignment of the place to stop clearing.  */
#if 0  /* This is not needed for gcc's purposes.  */
  /* If the block to clear is bigger than a cache plane,
     we clear the entire cache, and OFFSET is already correct.  */ 
  if (end < beg + INSN_CACHE_PLANE_SIZE)
#endif
    offset = (((int) (end + INSN_CACHE_LINE_WIDTH - 1)
	       & -INSN_CACHE_LINE_WIDTH)
	      & (INSN_CACHE_PLANE_SIZE - 1));

#if INSN_CACHE_DEPTH > 1
  end_addr = (start_addr & -INSN_CACHE_PLANE_SIZE) + offset;
  if (end_addr <= start_addr)
    end_addr += INSN_CACHE_PLANE_SIZE;

  for (plane = 0; plane < INSN_CACHE_DEPTH; plane++)
    {
      int addr = start_addr + plane * INSN_CACHE_PLANE_SIZE;
      int stop = end_addr + plane * INSN_CACHE_PLANE_SIZE;

      while (addr != stop)
	{
	  /* Call the return instruction at ADDR.  */
	  ((function_ptr) addr) ();

	  addr += INSN_CACHE_LINE_WIDTH;
	}
    }
#else /* just one plane */
  do
    {
      /* Call the return instruction at START_ADDR.  */
      ((function_ptr) start_addr) ();

      start_addr += INSN_CACHE_LINE_WIDTH;
    }
  while ((start_addr % INSN_CACHE_SIZE) != offset);
#endif /* just one plane */
#endif /* Cache is large */
#endif /* Cache exists */
}

#endif /* L_clear_cache */

#ifdef L_trampoline

/* Jump to a trampoline, loading the static chain address.  */

#ifdef TRANSFER_FROM_TRAMPOLINE 
TRANSFER_FROM_TRAMPOLINE 
#endif

#ifdef __convex__

/* Make stack executable so we can call trampolines on stack.
   This is called from INITIALIZE_TRAMPOLINE in convex.h.  */

#include <sys/mman.h>
#include <sys/vmparam.h>
#include <machine/machparam.h>

void
__enable_execute_stack ()
{
  int fp;
  static unsigned lowest = USRSTACK;
  unsigned current = (unsigned) &fp & -NBPG;

  if (lowest > current)
    {
      unsigned len = lowest - current;
      mremap (current, &len, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE);
      lowest = current;
    }

  /* Clear instruction cache in case an old trampoline is in it. */
  asm ("pich");
}
#endif /* __convex__ */

#ifdef __pyr__

#undef NULL /* Avoid errors if stdio.h and our stddef.h mismatch.  */
#include <stdio.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/param.h>
#include <sys/vmmac.h>

/* Modified from the convex -code above.
   mremap promises to clear the i-cache. */

void
__enable_execute_stack ()
{
  int fp;
  if (mprotect (((unsigned int)&fp/PAGSIZ)*PAGSIZ, PAGSIZ,
		PROT_READ|PROT_WRITE|PROT_EXEC))
    {
      perror ("mprotect in __enable_execute_stack");
      fflush (stderr);
      abort ();
    }
}
#endif /* __pyr__ */
#endif /* L_trampoline */

#ifdef L__main

#include "gbl-ctors.h"

/* Run all the global destructors on exit from the program.  */

void
__do_global_dtors ()
{
#ifdef DO_GLOBAL_DTORS_BODY
  DO_GLOBAL_DTORS_BODY;
#else
  unsigned nptrs = (unsigned HOST_WIDE_INT) __DTOR_LIST__[0];
  unsigned i;

  /* Some systems place the number of pointers
     in the first word of the table.
     On other systems, that word is -1.
     In all cases, the table is null-terminated.  */

  /* If the length is not recorded, count up to the null.  */
  if (nptrs == -1)
    for (nptrs = 0; __DTOR_LIST__[nptrs + 1] != 0; nptrs++);

  /* GNU LD format.  */
  for (i = nptrs; i >= 1; i--)
    __DTOR_LIST__[i] ();
#endif
}

#ifndef INIT_SECTION_ASM_OP
/* Run all the global constructors on entry to the program.  */

#ifndef ON_EXIT
#define ON_EXIT(a, b)
#else
/* Make sure the exit routine is pulled in to define the globals as
   bss symbols, just in case the linker does not automatically pull
   bss definitions from the library.  */

extern int _exit_dummy_decl;
int *_exit_dummy_ref = &_exit_dummy_decl;
#endif /* ON_EXIT */

void
__do_global_ctors ()
{
  DO_GLOBAL_CTORS_BODY;
  ON_EXIT (__do_global_dtors, 0);
}
#endif /* no INIT_SECTION_ASM_OP */

#if !defined (INIT_SECTION_ASM_OP) || defined (INVOKE__main)
/* Subroutine called automatically by `main'.
   Compiling a global function named `main'
   produces an automatic call to this function at the beginning.

   For many systems, this routine calls __do_global_ctors.
   For systems which support a .init section we use the .init section
   to run __do_global_ctors, so we need not do anything here.  */

void
__main ()
{
  /* Support recursive calls to `main': run initializers just once.  */
  static int initialized = 0;
  if (! initialized)
    {
      initialized = 1;
      __do_global_ctors ();
    }
}
#endif /* no INIT_SECTION_ASM_OP or INVOKE__main */

#endif /* L__main */

#ifdef L_ctors

#include "gbl-ctors.h"

/* Provide default definitions for the lists of constructors and
   destructors, so that we don't get linker errors.  These symbols are
   intentionally bss symbols, so that gld and/or collect will provide
   the right values.  */

/* We declare the lists here with two elements each,
   so that they are valid empty lists if no other definition is loaded.  */
#if !defined(INIT_SECTION_ASM_OP) && !defined(CTOR_LISTS_DEFINED_EXTERNALLY)
#ifdef __NeXT__
/* After 2.3, try this definition on all systems.  */
func_ptr __CTOR_LIST__[2] = {0, 0};
func_ptr __DTOR_LIST__[2] = {0, 0};
#else
func_ptr __CTOR_LIST__[2];
func_ptr __DTOR_LIST__[2];
#endif
#endif /* no INIT_SECTION_ASM_OP and not CTOR_LISTS_DEFINED_EXTERNALLY */
#endif /* L_ctors */

#ifdef L_exit

#include "gbl-ctors.h"

#ifndef ON_EXIT

/* If we have no known way of registering our own __do_global_dtors
   routine so that it will be invoked at program exit time, then we
   have to define our own exit routine which will get this to happen.  */

extern void __do_global_dtors ();
extern void _cleanup ();
extern volatile void _exit ();

void 
exit (status)
     int status;
{
  __do_global_dtors ();
#ifdef EXIT_BODY
  EXIT_BODY;
#else
  _cleanup ();
#endif
  _exit (status);
}

#else
int _exit_dummy_decl = 0;	/* prevent compiler & linker warnings */
#endif

#endif /* L_exit */

/* In a.out systems, we need to have these dummy constructor and destructor
   lists in the library.

   When using `collect', the first link will resolve __CTOR_LIST__
   and __DTOR_LIST__ to these symbols.  We will then run "nm" on the
   result, build the correct __CTOR_LIST__ and __DTOR_LIST__, and relink.
   Since we don't do the second link if no constructors existed, these
   dummies must be fully functional empty lists.

   When using `gnu ld', these symbols will be used if there are no
   constructors.  If there are constructors, the N_SETV symbol defined
   by the linker from the N_SETT's in input files will define __CTOR_LIST__
   and __DTOR_LIST__ rather than its being allocated as common storage
   by the definitions below.

   When using a linker that supports constructor and destructor segments,
   these definitions will not be used, since crtbegin.o and crtend.o
   (from crtstuff.c) will have already defined __CTOR_LIST__ and
    __DTOR_LIST__.  The crt*.o files are passed directly to the linker
   on its command line, by gcc.  */

/* The list needs two elements:  one is ignored (the old count); the
   second is the terminating zero.  Since both values are zero, this
   declaration is not initialized, and it becomes `common'.  */

#ifdef L_ctor_list
#include "gbl-ctors.h"
func_ptr __CTOR_LIST__[2];
#endif

#ifdef L_dtor_list
#include "gbl-ctors.h"
func_ptr __DTOR_LIST__[2];
#endif