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/* longlong.h -- definitions for mixed size 32/64 bit arithmetic.
   Copyright (C) 1991, 92, 94, 95, 96, 1997, 1998 Free Software Foundation, Inc.

   This definition file 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.

   This definition file 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 this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#define __BITS4 (SI_TYPE_SIZE / 4)
#define __ll_B (1L << (SI_TYPE_SIZE / 2))
#define __ll_lowpart(t) ((USItype) (t) % __ll_B)
#define __ll_highpart(t) ((USItype) (t) / __ll_B)

/* Define auxiliary macros.

   1) umul_ppmm(high_prod, low_prod, multipler, multiplicand)
   multiplies two USItype integers MULTIPLER and MULTIPLICAND,
   and generates a two-part USItype product in HIGH_PROD and
   LOW_PROD.

   2) __umulsidi3(a,b) multiplies two USItype integers A and B,
   and returns a UDItype product.  This is just a variant of umul_ppmm.

   3) udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
   denominator) divides a two-word unsigned integer, composed by the
   integers HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and
   places the quotient in QUOTIENT and the remainder in REMAINDER.
   HIGH_NUMERATOR must be less than DENOMINATOR for correct operation.
   The most significant bit of DENOMINATOR must be 1, which requires
   normalization.

   4) count_leading_zeros(count, x) counts the number of zero-bits from
   the msb to the first non-zero bit.  This is the number of steps X
   needs to be shifted left to set the msb.  Undefined for X == 0.

   5) sub_ddmmss(high_difference, low_difference, high_minuend,
   low_minuend, high_subtrahend, low_subtrahend) subtracts two
   two-word unsigned integers, composed by HIGH_MINUEND_1 and
   LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and LOW_SUBTRAHEND_2
   respectively.  The result is placed in HIGH_DIFFERENCE and
   LOW_DIFFERENCE.  Overflow (i.e. carry out) is not stored anywhere,
   and is lost.

   If any of these macros are left undefined for a particular CPU,
   C macros are used.  */

#define sub_ddmmss(sh, sl, ah, al, bh, bl) \
  do {									\
    USItype __x;							\
    __x = (al) - (bl);							\
    (sh) = (ah) - (bh) - (__x > (al));					\
    (sl) = __x;								\
  } while (0)

#define umul_ppmm(w1, w0, u, v)						\
  do {									\
    USItype __x0, __x1, __x2, __x3;					\
    USItype __ul, __vl, __uh, __vh;					\
									\
    __ul = __ll_lowpart (u);						\
    __uh = __ll_highpart (u);						\
    __vl = __ll_lowpart (v);						\
    __vh = __ll_highpart (v);						\
									\
    __x0 = (USItype) __ul * __vl;					\
    __x1 = (USItype) __ul * __vh;					\
    __x2 = (USItype) __uh * __vl;					\
    __x3 = (USItype) __uh * __vh;					\
									\
    __x1 += __ll_highpart (__x0);/* this can't give carry */		\
    __x1 += __x2;		/* but this indeed can */		\
    if (__x1 < __x2)		/* did we get it? */			\
      __x3 += __ll_B;		/* yes, add it in the proper pos. */	\
									\
    (w1) = __x3 + __ll_highpart (__x1);					\
    (w0) = __ll_lowpart (__x1) * __ll_B + __ll_lowpart (__x0);		\
  } while (0)

#define __umulsidi3(u, v) \
  ({DIunion __w;							\
    umul_ppmm (__w.s.high, __w.s.low, u, v);				\
    __w.ll; })

#define udiv_qrnnd(q, r, n1, n0, d) \
  do {									\
    USItype __d1, __d0, __q1, __q0;					\
    USItype __r1, __r0, __m;						\
    __d1 = __ll_highpart (d);						\
    __d0 = __ll_lowpart (d);						\
									\
    __r1 = (n1) % __d1;							\
    __q1 = (n1) / __d1;							\
    __m = (USItype) __q1 * __d0;					\
    __r1 = __r1 * __ll_B | __ll_highpart (n0);				\
    if (__r1 < __m)							\
      {									\
	__q1--, __r1 += (d);						\
	if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
	  if (__r1 < __m)						\
	    __q1--, __r1 += (d);					\
      }									\
    __r1 -= __m;							\
									\
    __r0 = __r1 % __d1;							\
    __q0 = __r1 / __d1;							\
    __m = (USItype) __q0 * __d0;					\
    __r0 = __r0 * __ll_B | __ll_lowpart (n0);				\
    if (__r0 < __m)							\
      {									\
	__q0--, __r0 += (d);						\
	if (__r0 >= (d))						\
	  if (__r0 < __m)						\
	    __q0--, __r0 += (d);					\
      }									\
    __r0 -= __m;							\
									\
    (q) = (USItype) __q1 * __ll_B | __q0;				\
    (r) = __r0;								\
  } while (0)

extern const UQItype __clz_tab[];
#define count_leading_zeros(count, x) \
  do {									\
    USItype __xr = (x);							\
    USItype __a;							\
									\
    if (SI_TYPE_SIZE <= 32)						\
      {									\
	__a = __xr < ((USItype)1<<2*__BITS4)				\
	  ? (__xr < ((USItype)1<<__BITS4) ? 0 : __BITS4)		\
	  : (__xr < ((USItype)1<<3*__BITS4) ?  2*__BITS4 : 3*__BITS4);	\
      }									\
    else								\
      {									\
	for (__a = SI_TYPE_SIZE - 8; __a > 0; __a -= 8)			\
	  if (((__xr >> __a) & 0xff) != 0)				\
	    break;							\
      }									\
									\
    (count) = SI_TYPE_SIZE - (__clz_tab[__xr >> __a] + __a);		\
  } while (0)