Subversion Repositories openrisc_me

/* Copyright (C) 2008, 2009 Free Software Foundation, Inc.

   This 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 3 of the License, or (at your option)

   any later version.

   This 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.

   Under Section 7 of GPL version 3, you are granted additional

   permissions described in the GCC Runtime Library Exception, version

   3.1, as published by the Free Software Foundation.

   You should have received a copy of the GNU General Public License and

   a copy of the GCC Runtime Library Exception along with this program;

   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see

   <http://www.gnu.org/licenses/>.  */

#include <spu_intrinsics.h>

typedef unsigned int UTItype __attribute__ ((mode (TI)));

typedef int TItype __attribute__ ((mode (TI)));

TItype __divti3 (TItype u, TItype v);

TItype __modti3 (TItype u, TItype v);

UTItype __udivti3 (UTItype u, UTItype v);

UTItype __umodti3 (UTItype u, UTItype v);

UTItype __udivmodti4 (UTItype u, UTItype v, UTItype *w);

inline static unsigned int

count_leading_zeros (UTItype x)

{

  qword c = si_clz (*(qword *) & x);

  qword cmp0 = si_cgti (c, 31);

  qword cmp1 = si_and (cmp0, si_shlqbyi (cmp0, 4));

  qword cmp2 = si_and (cmp1, si_shlqbyi (cmp0, 8));

  qword s = si_a (c, si_and (cmp0, si_shlqbyi (c, 4)));

  s = si_a (s, si_and (cmp1, si_shlqbyi (c, 8)));

  s = si_a (s, si_and (cmp2, si_shlqbyi (c, 12)));

  return si_to_uint (s);

}

/* Based on implementation of udivmodsi4, which is essentially

 * an optimized version of gcc/config/udivmodsi4.c

        clz      %7,%2

        clz      %4,%1

        il       %5,1

        fsmbi    %0,0

        sf       %7,%4,%7

        ori      %3,%1,0

        shl      %5,%5,%7

        shl      %4,%2,%7

1:      or       %8,%0,%5

        rotmi    %5,%5,-1

        clgt     %6,%4,%3

        sf       %7,%4,%3

        rotmi    %4,%4,-1

        selb     %0,%8,%0,%6

        selb     %3,%7,%3,%6

3:      brnz     %5,1b

 */

UTItype

__udivmodti4 (UTItype num, UTItype den, UTItype * rp)

{

  qword shift =

    si_from_uint (count_leading_zeros (den) - count_leading_zeros (num));

  qword n0 = *(qword *) & num;

  qword d0 = *(qword *) & den;

  qword bit = si_andi (si_fsmbi (1), 1);

  qword r0 = si_il (0);

  qword m1 = si_fsmbi (0x000f);

  qword mask, r1, n1;

  d0 = si_shlqbybi (si_shlqbi (d0, shift), shift);

  bit = si_shlqbybi (si_shlqbi (bit, shift), shift);

  do

    {

      r1 = si_or (r0, bit);

      // n1 = n0 - d0 in TImode

      n1 = si_bg (d0, n0);

      n1 = si_shlqbyi (n1, 4);

      n1 = si_sf (m1, n1);

      n1 = si_bgx (d0, n0, n1);

      n1 = si_shlqbyi (n1, 4);

      n1 = si_sf (m1, n1);

      n1 = si_bgx (d0, n0, n1);

      n1 = si_shlqbyi (n1, 4);

      n1 = si_sf (m1, n1);

      n1 = si_sfx (d0, n0, n1);

      mask = si_fsm (si_cgti (n1, -1));

      r0 = si_selb (r0, r1, mask);

      n0 = si_selb (n0, n1, mask);

      bit = si_rotqmbii (bit, -1);

      d0 = si_rotqmbii (d0, -1);

    }

  while (si_to_uint (si_orx (bit)));

  if (rp)

    *rp = *(UTItype *) & n0;

  return *(UTItype *) & r0;

}

UTItype

__udivti3 (UTItype n, UTItype d)

{

  return __udivmodti4 (n, d, (UTItype *)0);

}

UTItype

__umodti3 (UTItype n, UTItype d)

{

  UTItype w;

  __udivmodti4 (n, d, &w);

  return w;

}

TItype

__divti3 (TItype n, TItype d)

{

  int c = 0;

  TItype w;

  if (n < 0)

    {

        c = ~c;

        n = -n;

    }

  if (d < 0)

    {

        c = ~c;

        d = -d;

    }

  w = __udivmodti4 (n, d, (UTItype *)0);

  if (c)

    w = -w;

  return w;

}

TItype

__modti3 (TItype n, TItype d)

{

  int c = 0;

  TItype w;

  if (n < 0)

    {

        c = ~c;

        n = -n;

    }

  if (d < 0)

    {

        c = ~c;

        d = -d;

    }

  __udivmodti4 (n, d, (UTItype *) &w);

  if (c)

    w = -w;

  return w;

}