libgcc2.c

GCC编译器源代码

		 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;
		  rr.s.high = n1;
		  *rp = rr.ll;
		}
	    }
	  else
	    {
	      USItype m1, m0;
	      /* Normalize.  */

	      b = SI_TYPE_SIZE - bm;

	      d1 = (d1 << bm) | (d0 >> b);
	      d0 = d0 << bm;
	      n2 = n1 >> b;
	      n1 = (n1 << bm) | (n0 >> b);
	      n0 = n0 << bm;

	      udiv_qrnnd (q0, n1, n2, n1, d1);
	      umul_ppmm (m1, m0, q0, d0);

	      if (m1 > n1 || (m1 == n1 && m0 > n0))
		{
		  q0--;
		  sub_ddmmss (m1, m0, m1, m0, d1, d0);
		}

	      q1 = 0;

	      /* Remainder in (n1n0 - m1m0) >> bm.  */
	      if (rp != 0)
		{
		  sub_ddmmss (n1, n0, n1, n0, m1, m0);
		  rr.s.low = (n1 << b) | (n0 >> bm);
		  rr.s.high = n1 >> bm;
		  *rp = rr.ll;
		}
	    }
	}
    }

  ww.s.low = q0;
  ww.s.high = q1;
  return ww.ll;
}
#endif

#ifdef L_divdi3
UDItype __udivmoddi4 ();

DItype
__divdi3 (DItype u, DItype v)
{
  word_type c = 0;
  DIunion uu, vv;
  DItype w;

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

  if (uu.s.high < 0)
    c = ~c,
    uu.ll = __negdi2 (uu.ll);
  if (vv.s.high < 0)
    c = ~c,
    vv.ll = __negdi2 (vv.ll);

  w = __udivmoddi4 (uu.ll, vv.ll, (UDItype *) 0);
  if (c)
    w = __negdi2 (w);

  return w;
}
#endif

#ifdef L_moddi3
UDItype __udivmoddi4 ();
DItype
__moddi3 (DItype u, DItype v)
{
  word_type c = 0;
  DIunion uu, vv;
  DItype w;

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

  if (uu.s.high < 0)
    c = ~c,
    uu.ll = __negdi2 (uu.ll);
  if (vv.s.high < 0)
    vv.ll = __negdi2 (vv.ll);

  (void) __udivmoddi4 (uu.ll, vv.ll, &w);
  if (c)
    w = __negdi2 (w);

  return w;
}
#endif

#ifdef L_umoddi3
UDItype __udivmoddi4 ();
UDItype
__umoddi3 (UDItype u, UDItype v)
{
  UDItype w;

  (void) __udivmoddi4 (u, v, &w);

  return w;
}
#endif

#ifdef L_udivdi3
UDItype __udivmoddi4 ();
UDItype
__udivdi3 (UDItype n, UDItype d)
{
  return __udivmoddi4 (n, d, (UDItype *) 0);
}
#endif

#ifdef L_cmpdi2
word_type
__cmpdi2 (DItype a, DItype b)
{
  DIunion au, bu;

  au.ll = a, bu.ll = b;

  if (au.s.high < bu.s.high)
    return 0;
  else if (au.s.high > bu.s.high)
    return 2;
  if ((USItype) au.s.low < (USItype) bu.s.low)
    return 0;
  else if ((USItype) au.s.low > (USItype) bu.s.low)
    return 2;
  return 1;
}
#endif

#ifdef L_ucmpdi2
word_type
__ucmpdi2 (DItype a, DItype b)
{
  DIunion au, bu;

  au.ll = a, bu.ll = b;

  if ((USItype) au.s.high < (USItype) bu.s.high)
    return 0;
  else if ((USItype) au.s.high > (USItype) bu.s.high)
    return 2;
  if ((USItype) au.s.low < (USItype) bu.s.low)
    return 0;
  else if ((USItype) au.s.low > (USItype) bu.s.low)
    return 2;
  return 1;
}
#endif

#if defined(L_fixunstfdi) && (LONG_DOUBLE_TYPE_SIZE == 128)
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)

DItype
__fixunstfdi (TFtype a)
{
  TFtype b;
  UDItype v;

  if (a < 0)
    return 0;

  /* Compute high word of result, as a flonum.  */
  b = (a / HIGH_WORD_COEFF);
  /* Convert that to fixed (but not to DItype!),
     and shift it into the high word.  */
  v = (USItype) b;
  v <<= WORD_SIZE;
  /* Remove high part from the TFtype, leaving the low part as flonum.  */
  a -= (TFtype)v;
  /* Convert that to fixed (but not to DItype!) and add it in.
     Sometimes A comes out negative.  This is significant, since
     A has more bits than a long int does.  */
  if (a < 0)
    v -= (USItype) (- a);
  else
    v += (USItype) a;
  return v;
}
#endif

#if defined(L_fixtfdi) && (LONG_DOUBLE_TYPE_SIZE == 128)
DItype
__fixtfdi (TFtype a)
{
  if (a < 0)
    return - __fixunstfdi (-a);
  return __fixunstfdi (a);
}
#endif

#if defined(L_fixunsxfdi) && (LONG_DOUBLE_TYPE_SIZE == 96)
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)

DItype
__fixunsxfdi (XFtype a)
{
  XFtype b;
  UDItype v;

  if (a < 0)
    return 0;

  /* Compute high word of result, as a flonum.  */
  b = (a / HIGH_WORD_COEFF);
  /* Convert that to fixed (but not to DItype!),
     and shift it into the high word.  */
  v = (USItype) b;
  v <<= WORD_SIZE;
  /* Remove high part from the XFtype, leaving the low part as flonum.  */
  a -= (XFtype)v;
  /* Convert that to fixed (but not to DItype!) and add it in.
     Sometimes A comes out negative.  This is significant, since
     A has more bits than a long int does.  */
  if (a < 0)
    v -= (USItype) (- a);
  else
    v += (USItype) a;
  return v;
}
#endif

#if defined(L_fixxfdi) && (LONG_DOUBLE_TYPE_SIZE == 96)
DItype
__fixxfdi (XFtype a)
{
  if (a < 0)
    return - __fixunsxfdi (-a);
  return __fixunsxfdi (a);
}
#endif

#ifdef L_fixunsdfdi
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)

DItype
__fixunsdfdi (DFtype a)
{
  DFtype b;
  UDItype v;

  if (a < 0)
    return 0;

  /* Compute high word of result, as a flonum.  */
  b = (a / HIGH_WORD_COEFF);
  /* Convert that to fixed (but not to DItype!),
     and shift it into the high word.  */
  v = (USItype) b;
  v <<= WORD_SIZE;
  /* Remove high part from the DFtype, leaving the low part as flonum.  */
  a -= (DFtype)v;
  /* Convert that to fixed (but not to DItype!) and add it in.
     Sometimes A comes out negative.  This is significant, since
     A has more bits than a long int does.  */
  if (a < 0)
    v -= (USItype) (- a);
  else
    v += (USItype) a;
  return v;
}
#endif

#ifdef L_fixdfdi
DItype
__fixdfdi (DFtype a)
{
  if (a < 0)
    return - __fixunsdfdi (-a);
  return __fixunsdfdi (a);
}
#endif

#ifdef L_fixunssfdi
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)

DItype
__fixunssfdi (SFtype original_a)
{
  /* Convert the SFtype to a DFtype, because that is surely not going
     to lose any bits.  Some day someone else can write a faster version
     that avoids converting to DFtype, and verify it really works right.  */
  DFtype a = original_a;
  DFtype b;
  UDItype v;

  if (a < 0)
    return 0;

  /* Compute high word of result, as a flonum.  */
  b = (a / HIGH_WORD_COEFF);
  /* Convert that to fixed (but not to DItype!),
     and shift it into the high word.  */
  v = (USItype) b;
  v <<= WORD_SIZE;
  /* Remove high part from the DFtype, leaving the low part as flonum.  */
  a -= (DFtype)v;
  /* Convert that to fixed (but not to DItype!) and add it in.
     Sometimes A comes out negative.  This is significant, since
     A has more bits than a long int does.  */
  if (a < 0)
    v -= (USItype) (- a);
  else
    v += (USItype) a;
  return v;
}
#endif

#ifdef L_fixsfdi
DItype
__fixsfdi (SFtype a)
{
  if (a < 0)
    return - __fixunssfdi (-a);
  return __fixunssfdi (a);
}
#endif

#if defined(L_floatdixf) && (LONG_DOUBLE_TYPE_SIZE == 96)
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_HALFWORD_COEFF (((UDItype) 1) << (WORD_SIZE / 2))
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)

XFtype
__floatdixf (DItype u)
{
  XFtype d;
  SItype negate = 0;

  if (u < 0)
    u = -u, negate = 1;

  d = (USItype) (u >> WORD_SIZE);
  d *= HIGH_HALFWORD_COEFF;
  d *= HIGH_HALFWORD_COEFF;
  d += (USItype) (u & (HIGH_WORD_COEFF - 1));

  return (negate ? -d : d);
}
#endif

#if defined(L_floatditf) && (LONG_DOUBLE_TYPE_SIZE == 128)
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_HALFWORD_COEFF (((UDItype) 1) << (WORD_SIZE / 2))
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)

TFtype
__floatditf (DItype u)
{
  TFtype d;
  SItype negate = 0;

  if (u < 0)
    u = -u, negate = 1;

  d = (USItype) (u >> WORD_SIZE);
  d *= HIGH_HALFWORD_COEFF;
  d *= HIGH_HALFWORD_COEFF;
  d += (USItype) (u & (HIGH_WORD_COEFF - 1));

  return (negate ? -d : d);
}
#endif

#ifdef L_floatdidf
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_HALFWORD_COEFF (((UDItype) 1) << (WORD_SIZE / 2))
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)

DFtype
__floatdidf (DItype u)
{
  DFtype d;
  SItype negate = 0;

  if (u < 0)
    u = -u, negate = 1;

  d = (USItype) (u >> WORD_SIZE);
  d *= HIGH_HALFWORD_COEFF;
  d *= HIGH_HALFWORD_COEFF;
  d += (USItype) (u & (HIGH_WORD_COEFF - 1));

  return (negate ? -d : d);
}
#endif

#ifdef L_floatdisf
#define WORD_SIZE (sizeof (SItype) * BITS_PER_UNIT)
#define HIGH_HALFWORD_COEFF (((UDItype) 1) << (WORD_SIZE / 2))
#define HIGH_WORD_COEFF (((UDItype) 1) << WORD_SIZE)
#define DI_SIZE (sizeof (DItype) * BITS_PER_UNIT)

/* Define codes for all the float formats that we know of.  Note
   that this is copied from real.h.  */
   
#define UNKNOWN_FLOAT_FORMAT 0
#define IEEE_FLOAT_FORMAT 1
#define VAX_FLOAT_FORMAT 2
#define IBM_FLOAT_FORMAT 3

/* Default to IEEE float if not specified.  Nearly all machines use it.  */
#ifndef HOST_FLOAT_FORMAT
#define	HOST_FLOAT_FORMAT	IEEE_FLOAT_FORMAT
#endif

#if HOST_FLOAT_FORMAT == IEEE_FLOAT_FORMAT
#define DF_SIZE 53
#define SF_SIZE 24
#endif

#if HOST_FLOAT_FORMAT == IBM_FLOAT_FORMAT
#define DF_SIZE 56
#define SF_SIZE 24
#endif

#if HOST_FLOAT_FORMAT == VAX_FLOAT_FORMAT
#define DF_SIZE 56
#define SF_SIZE 24
#endif

SFtype
__floatdisf (DItype u)
{
  /* Do the calculation in DFmode
     so that we don't lose any of the precision of the high word
     while multiplying it.  */
  DFtype f;
  SItype negate = 0;

  if (u < 0)
    u = -u, negate = 1;

  /* Protect against double-rounding error.
     Represent any low-order bits, that might be truncated in DFmode,
     by a bit that won't be lost.  The bit can go in anywhere below the
     rounding position of the SFmode.  A fixed mask and bit position
     handles all usual configurations.  It doesn't handle the case
     of 128-bit DImode, however.  */
  if (DF_SIZE < DI_SIZE
      && DF_SIZE > (DI_SIZE - DF_SIZE + SF_SIZE))
    {
#define REP_BIT ((USItype) 1 << (DI_SIZE - DF_SIZE))
      if (u >= ((UDItype) 1 << DF_SIZE))
	{
	  if ((USItype) u & (REP_BIT - 1))
	    u |= REP_BIT;
	}
    }
  f = (USItype) (u >> WORD_SIZE);
  f *= HIGH_HALFWORD_COEFF;
  f *= HIGH_HALFWORD_COEFF;
  f += (USItype) (u & (HIGH_WORD_COEFF - 1));

  return (SFtype) (negate ? -f : f);
}
#endif

#if defined(L_fixunsxfsi) && LONG_DOUBLE_TYPE_SIZE == 96
/* Reenable the normal types, in case limits.h needs them.  */
#undef char
#undef short
#undef int
#undef long
#undef unsigned
#undef float
#undef double
#undef MIN
#undef MAX
#include <limits.h>

USItype
__fixunsxfsi (XFtype a)
{
  if (a >= - (DFtype) LONG_MIN)
    return (SItype) (a + LONG_MIN) - LONG_MIN;
  return (SItype) a;
}
#endif

#ifdef L_fixunsdfsi
/* Reenable the normal types, in case limits.h needs them.  */
#undef char
#undef short
#undef int
#undef long
#undef unsigned
#undef float
#undef double
#undef MIN
#undef MAX
#include <limits.h>

USItype
__fixunsdfsi (DFtype a)
{
  if (a >= - (DFtype) LONG_MIN)
    return (SItype) (a + LONG_MIN) - LONG_MIN;
  return (SItype) a;
}
#endif

#ifdef L_fixunssfsi
/* Reenable the normal types, in case limits.h needs them.  */
#undef char
#undef short
#undef int
#undef long
#undef unsigned
#undef float
#undef double
#undef MIN
#undef MAX
#include <limits.h>

USItype
__fixunssfsi (SFtype a)
{
  if (a >= - (SFtype) LONG_MIN)
    return (SItype) (a + LONG_MIN) - LONG_MIN;
  return (SItype) a;
}
#endif

/* From here on down, the routines use normal data types.  */

#define SItype bogus_type
#define USItype bogus_type
#define DItype bogus_type
#define UDItype bogus_type
#define SFtype bogus_type
#define DFtype bogus_type

#undef char
#undef short
#undef int
#undef long
#undef unsigned
#undef float
#undef double

#ifdef L__gcc_bcmp