libgcc2.c

这是一个开放源代码的与WINNT/WIN2K/WIN2003兼容的操作系统

/* More subroutines needed by GCC output code on some machines.  */
/* Compile this one with gcc.  */
/* Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   2000, 2001  Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.

In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file.  (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combine
executable.)

GCC is distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING.  If not, write to the Free
Software Foundation, 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.  */

/* It is incorrect to include config.h here, because this file is being
   compiled for the target, and hence definitions concerning only the host
   do not apply.  */

/*
 * This file was taken from the GCC v3.1 source - Brian
 */
#ifdef __i386__
#include "i386.h"
#elif defined(_M_PPC)
#include "powerpc.h"
#endif
#define L_clz
#define L_udivdi3
#define L_umoddi3
#include <freeldr.h>

//#include "tconfig.h"
//#include "tsystem.h"

//#include "machmode.h"

/* Don't use `fancy_abort' here even if config.h says to use it.  */
#ifdef abort
#undef abort
#endif

#include "libgcc2.h"

#if defined (L_negdi2) || defined (L_divdi3) || defined (L_moddi3)
#if defined (L_divdi3) || defined (L_moddi3)
static __inline
#endif
DWtype
__negdi2 (DWtype u)
{
  DWunion w;
  DWunion uu;

  uu.ll = u;

  w.s.low = -uu.s.low;
  w.s.high = -uu.s.high - ((UWtype) w.s.low > 0);

  return w.ll;
}
#endif

#ifdef L_addvsi3
Wtype
__addvsi3 (Wtype a, Wtype b)
{
  Wtype w;

  w = a + b;

  if (b >= 0 ? w < a : w > a)
    abort ();

  return w;
}
#endif

#ifdef L_addvdi3
DWtype
__addvdi3 (DWtype a, DWtype b)
{
  DWtype w;

  w = a + b;

  if (b >= 0 ? w < a : w > a)
    abort ();

  return w;
}
#endif

#ifdef L_subvsi3
Wtype
__subvsi3 (Wtype a, Wtype b)
{
#ifdef L_addvsi3
  return __addvsi3 (a, (-b));
#else
  DWtype w;

  w = a - b;

  if (b >= 0 ? w > a : w < a)
    abort ();

  return w;
#endif
}
#endif

#ifdef L_subvdi3
DWtype
__subvdi3 (DWtype a, DWtype b)
{
#ifdef L_addvdi3
  return (a, (-b));
#else
  DWtype w;

  w = a - b;

  if (b >= 0 ? w > a : w < a)
    abort ();

  return w;
#endif
}
#endif

#ifdef L_mulvsi3
Wtype
__mulvsi3 (Wtype a, Wtype b)
{
  DWtype w;

  w = a * b;

  if (((a >= 0) == (b >= 0)) ? w < 0 : w > 0)
    abort ();

  return w;
}
#endif

#ifdef L_negvsi2
Wtype
__negvsi2 (Wtype a)
{
   Wtype w;

   w  = -a;

  if (a >= 0 ? w > 0 : w < 0)
    abort ();

   return w;
}
#endif

#ifdef L_negvdi2
DWtype
__negvdi2 (DWtype a)
{
   DWtype w;

   w  = -a;

  if (a >= 0 ? w > 0 : w < 0)
    abort ();

   return w;
}
#endif

#ifdef L_absvsi2
Wtype
__absvsi2 (Wtype a)
{
   Wtype w = a;

   if (a < 0)
#ifdef L_negvsi2
     w = __negvsi2 (a);
#else
     w = -a;

   if (w < 0)
     abort ();
#endif

   return w;
}
#endif

#ifdef L_absvdi2
DWtype
__absvdi2 (DWtype a)
{
   DWtype w = a;

   if (a < 0)
#ifdef L_negvsi2
     w = __negvsi2 (a);
#else
     w = -a;

   if (w < 0)
     abort ();
#endif

   return w;
}
#endif

#ifdef L_mulvdi3
DWtype
__mulvdi3 (DWtype u, DWtype v)
{
   DWtype w;

  w = u * v;

  if (((u >= 0) == (v >= 0)) ? w < 0 : w > 0)
    abort ();

  return w;
}
#endif


/* Unless shift functions are defined whith full ANSI prototypes,
   parameter b will be promoted to int if word_type is smaller than an int.  */
#ifdef L_lshrdi3
DWtype
__lshrdi3 (DWtype u, word_type b)
{
  DWunion w;
  word_type bm;
  DWunion uu;

  if (b == 0)
    return u;

  uu.ll = u;

  bm = (sizeof (Wtype) * BITS_PER_UNIT) - b;
  if (bm <= 0)
    {
      w.s.high = 0;
      w.s.low = (UWtype) uu.s.high >> -bm;
    }
  else
    {
      UWtype carries = (UWtype) uu.s.high << bm;

      w.s.high = (UWtype) uu.s.high >> b;
      w.s.low = ((UWtype) uu.s.low >> b) | carries;
    }

  return w.ll;
}
#endif

#ifdef L_ashldi3
DWtype
__ashldi3 (DWtype u, word_type b)
{
  DWunion w;
  word_type bm;
  DWunion uu;

  if (b == 0)
    return u;

  uu.ll = u;

  bm = (sizeof (Wtype) * BITS_PER_UNIT) - b;
  if (bm <= 0)
    {
      w.s.low = 0;
      w.s.high = (UWtype) uu.s.low << -bm;
    }
  else
    {
      UWtype carries = (UWtype) uu.s.low >> bm;

      w.s.low = (UWtype) uu.s.low << b;
      w.s.high = ((UWtype) uu.s.high << b) | carries;
    }

  return w.ll;
}
#endif

#ifdef L_ashrdi3
DWtype
__ashrdi3 (DWtype u, word_type b)
{
  DWunion w;
  word_type bm;
  DWunion uu;

  if (b == 0)
    return u;

  uu.ll = u;

  bm = (sizeof (Wtype) * BITS_PER_UNIT) - b;
  if (bm <= 0)
    {
      /* w.s.high = 1..1 or 0..0 */
      w.s.high = uu.s.high >> (sizeof (Wtype) * BITS_PER_UNIT - 1);
      w.s.low = uu.s.high >> -bm;
    }
  else
    {
      UWtype carries = (UWtype) uu.s.high << bm;

      w.s.high = uu.s.high >> b;
      w.s.low = ((UWtype) uu.s.low >> b) | carries;
    }

  return w.ll;
}
#endif

#ifdef L_ffsdi2
DWtype
__ffsdi2 (DWtype u)
{
  DWunion uu;
  UWtype word, count, add;

  uu.ll = u;
  if (uu.s.low != 0)
    word = uu.s.low, add = 0;
  else if (uu.s.high != 0)
    word = uu.s.high, add = BITS_PER_UNIT * sizeof (Wtype);
  else
    return 0;

  count_trailing_zeros (count, word);
  return count + add + 1;
}
#endif

#ifdef L_muldi3
DWtype
__muldi3 (DWtype u, DWtype v)
{
  DWunion w;
  DWunion uu, vv;

  uu.ll = u,
  vv.ll = v;

  w.ll = __umulsidi3 (uu.s.low, vv.s.low);
  w.s.high += ((UWtype) uu.s.low * (UWtype) vv.s.high
	       + (UWtype) uu.s.high * (UWtype) vv.s.low);

  return w.ll;
}
#endif

#ifdef L_udiv_w_sdiv
#if defined (sdiv_qrnnd)
UWtype
__udiv_w_sdiv (UWtype *rp, UWtype a1, UWtype a0, UWtype d)
{
  UWtype q, r;
  UWtype c0, c1, b1;

  if ((Wtype) d >= 0)
    {
      if (a1 < d - a1 - (a0 >> (W_TYPE_SIZE - 1)))
	{
	  /* dividend, divisor, and quotient are nonnegative */
	  sdiv_qrnnd (q, r, a1, a0, d);
	}
      else
	{
	  /* Compute c1*2^32 + c0 = a1*2^32 + a0 - 2^31*d */
	  sub_ddmmss (c1, c0, a1, a0, d >> 1, d << (W_TYPE_SIZE - 1));
	  /* Divide (c1*2^32 + c0) by d */
	  sdiv_qrnnd (q, r, c1, c0, d);
	  /* Add 2^31 to quotient */
	  q += (UWtype) 1 << (W_TYPE_SIZE - 1);
	}
    }
  else
    {
      b1 = d >> 1;			/* d/2, between 2^30 and 2^31 - 1 */
      c1 = a1 >> 1;			/* A/2 */
      c0 = (a1 << (W_TYPE_SIZE - 1)) + (a0 >> 1);

      if (a1 < b1)			/* A < 2^32*b1, so A/2 < 2^31*b1 */
	{
	  sdiv_qrnnd (q, r, c1, c0, b1); /* (A/2) / (d/2) */

	  r = 2*r + (a0 & 1);		/* Remainder from A/(2*b1) */
	  if ((d & 1) != 0)
	    {
	      if (r >= q)
		r = r - q;
	      else if (q - r <= d)
		{
		  r = r - q + d;
		  q--;
		}
	      else
		{
		  r = r - q + 2*d;
		  q -= 2;
		}
	    }
	}
      else if (c1 < b1)			/* So 2^31 <= (A/2)/b1 < 2^32 */
	{
	  c1 = (b1 - 1) - c1;
	  c0 = ~c0;			/* logical NOT */

	  sdiv_qrnnd (q, r, c1, c0, b1); /* (A/2) / (d/2) */

	  q = ~q;			/* (A/2)/b1 */
	  r = (b1 - 1) - r;

	  r = 2*r + (a0 & 1);		/* A/(2*b1) */

	  if ((d & 1) != 0)
	    {
	      if (r >= q)
		r = r - q;
	      else if (q - r <= d)
		{
		  r = r - q + d;
		  q--;
		}
	      else
		{
		  r = r - q + 2*d;
		  q -= 2;
		}
	    }
	}
      else				/* Implies c1 = b1 */
	{				/* Hence a1 = d - 1 = 2*b1 - 1 */
	  if (a0 >= -d)
	    {
	      q = -1;
	      r = a0 + d;
	    }
	  else
	    {
	      q = -2;
	      r = a0 + 2*d;
	    }
	}
    }

  *rp = r;
  return q;
}
#else
/* If sdiv_qrnnd doesn't exist, define dummy __udiv_w_sdiv.  */
UWtype
__udiv_w_sdiv (UWtype *rp __attribute__ ((__unused__)),
	       UWtype a1 __attribute__ ((__unused__)),
	       UWtype a0 __attribute__ ((__unused__)),
	       UWtype d __attribute__ ((__unused__)))
{
  return 0;
}
#endif
#endif

#if (defined (L_udivdi3) || defined (L_divdi3) || \
     defined (L_umoddi3) || defined (L_moddi3))
#define L_udivmoddi4
#endif

#ifdef L_clz
const UQItype __clz_tab[] =
{
  0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
  6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
  7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
  7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,
  8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
  8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
  8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
  8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
};
#endif

#ifdef L_udivmoddi4

#if (defined (L_udivdi3) || defined (L_divdi3) || \
     defined (L_umoddi3) || defined (L_moddi3))
static __inline
#endif
UDWtype
__udivmoddi4 (UDWtype n, UDWtype d, UDWtype *rp)
{
  DWunion ww;
  DWunion nn, dd;
  DWunion rr;
  UWtype d0, d1, n0, n1, n2;
  UWtype q0, q1;
  UWtype b, bm;

  nn.ll = n;
  dd.ll = d;

  d0 = dd.s.low;
  d1 = dd.s.high;
  n0 = nn.s.low;
  n1 = nn.s.high;

#if !UDIV_NEEDS_NORMALIZATION
  if (d1 == 0)
    {
      if (d0 > n1)
	{
	  /* 0q = nn / 0D */

	  udiv_qrnnd (q0, n0, n1, n0, d0);
	  q1 = 0;

	  /* Remainder in n0.  */
	}
      else
	{
	  /* qq = NN / 0d */

	  if (d0 == 0)
	    d0 = 1 / d0;	/* Divide intentionally by zero.  */

	  udiv_qrnnd (q1, n1, 0, n1, d0);
	  udiv_qrnnd (q0, n0, n1, n0, d0);

	  /* Remainder in n0.  */
	}

      if (rp != 0)
	{
	  rr.s.low = n0;
	  rr.s.high = 0;
	  *rp = rr.ll;
	}
    }

#else /* UDIV_NEEDS_NORMALIZATION */

  if (d1 == 0)
    {
      if (d0 > n1)
	{
	  /* 0q = nn / 0D */

	  count_leading_zeros (bm, d0);

	  if (bm != 0)
	    {
	      /* Normalize, i.e. make the most significant bit of the
		 denominator set.  */

	      d0 = d0 << bm;
	      n1 = (n1 << bm) | (n0 >> (W_TYPE_SIZE - bm));
	      n0 = n0 << bm;
	    }

	  udiv_qrnnd (q0, n0, n1, n0, d0);
	  q1 = 0;

	  /* Remainder in n0 >> bm.  */
	}
      else
	{
	  /* qq = NN / 0d */

	  if (d0 == 0)
	    d0 = 1 / d0;	/* Divide intentionally by zero.  */

	  count_leading_zeros (bm, d0);

	  if (bm == 0)
	    {
	      /* From (n1 >= d0) /\ (the most significant bit of d0 is set),
		 conclude (the most significant bit of n1 is set) /\ (the
		 leading quotient digit q1 = 1).

		 This special case is necessary, not an optimization.
		 (Shifts counts of W_TYPE_SIZE are undefined.)  */

	      n1 -= d0;
	      q1 = 1;
	    }
	  else
	    {
	      /* Normalize.  */

	      b = W_TYPE_SIZE - bm;

	      d0 = d0 << bm;
	      n2 = n1 >> b;
	      n1 = (n1 << bm) | (n0 >> b);
	      n0 = n0 << bm;

	      udiv_qrnnd (q1, n1, n2, n1, d0);
	    }

	  /* n1 != d0...  */

	  udiv_qrnnd (q0, n0, n1, n0, d0);

	  /* Remainder in n0 >> bm.  */
	}

      if (rp != 0)
	{
	  rr.s.low = n0 >> bm;
	  rr.s.high = 0;
	  *rp = rr.ll;
	}
    }
#endif /* UDIV_NEEDS_NORMALIZATION */

  else
    {
      if (d1 > n1)
	{
	  /* 00 = nn / DD */

	  q0 = 0;
	  q1 = 0;

	  /* Remainder in n1n0.  */
	  if (rp != 0)
	    {
	      rr.s.low = n0;
	      rr.s.high = n1;
	      *rp = rr.ll;
	    }
	}
      else
	{
	  /* 0q = NN / dd */

	  count_leading_zeros (bm, d1);
	  if (bm == 0)
	    {
	      /* From (n1 >= d1) /\ (the most significant bit of d1 is set),
		 conclude (the most significant bit of n1 is set) /\ (the
		 quotient digit q0 = 0 or 1).

		 This special case is necessary, not an optimization.  */

	      /* The condition on the next line takes advantage of that
		 n1 >= d1 (true due to program flow).  */
	      if (n1 > d1 || n0 >= d0)
		{
		  q0 = 1;
		  sub_ddmmss (n1, n0, n1, n0, d1, d0);
		}
	      else
		q0 = 0;

	      q1 = 0;

	      if (rp != 0)
		{
		  rr.s.low = n0;