kernel/linux/arch/arm/lib/longlong.h

   1 /* longlong.h -- based on code from gcc-2.95.3
   2
   3    definitions for mixed size 32/64 bit arithmetic.
   4    Copyright (C) 1991, 92, 94, 95, 96, 1997, 1998 Free Software Foundation, Inc.
   5
   6    This definition file is free software; you can redistribute it
   7    and/or modify it under the terms of the GNU General Public
   8    License as published by the Free Software Foundation; either
   9    version 2, or (at your option) any later version.
  10
  11    This definition file is distributed in the hope that it will be
  12    useful, but WITHOUT ANY WARRANTY; without even the implied
  13    warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  14    See the GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 /* Borrowed from GCC 2.95.3, I Molton 29/07/01 */
  22
  23 #ifndef SI_TYPE_SIZE
  24 #define SI_TYPE_SIZE 32
  25 #endif
  26
  27 #define __BITS4 (SI_TYPE_SIZE / 4)
  28 #define __ll_B (1L << (SI_TYPE_SIZE / 2))
  29 #define __ll_lowpart(t) ((USItype) (t) % __ll_B)
  30 #define __ll_highpart(t) ((USItype) (t) / __ll_B)
  31
  32 /* Define auxiliary asm macros.
  33
  34    1) umul_ppmm(high_prod, low_prod, multipler, multiplicand)
  35    multiplies two USItype integers MULTIPLER and MULTIPLICAND,
  36    and generates a two-part USItype product in HIGH_PROD and
  37    LOW_PROD.
  38
  39    2) __umulsidi3(a,b) multiplies two USItype integers A and B,
  40    and returns a UDItype product.  This is just a variant of umul_ppmm.
  41
  42    3) udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
  43    denominator) divides a two-word unsigned integer, composed by the
  44    integers HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and
  45    places the quotient in QUOTIENT and the remainder in REMAINDER.
  46    HIGH_NUMERATOR must be less than DENOMINATOR for correct operation.
  47    If, in addition, the most significant bit of DENOMINATOR must be 1,
  48    then the pre-processor symbol UDIV_NEEDS_NORMALIZATION is defined to 1.
  49
  50    4) sdiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
  51    denominator).  Like udiv_qrnnd but the numbers are signed.  The
  52    quotient is rounded towards 0.
  53
  54    5) count_leading_zeros(count, x) counts the number of zero-bits from
  55    the msb to the first non-zero bit.  This is the number of steps X
  56    needs to be shifted left to set the msb.  Undefined for X == 0.
  57
  58    6) add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,
  59    high_addend_2, low_addend_2) adds two two-word unsigned integers,
  60    composed by HIGH_ADDEND_1 and LOW_ADDEND_1, and HIGH_ADDEND_2 and
  61    LOW_ADDEND_2 respectively.  The result is placed in HIGH_SUM and
  62    LOW_SUM.  Overflow (i.e. carry out) is not stored anywhere, and is
  63    lost.
  64
  65    7) sub_ddmmss(high_difference, low_difference, high_minuend,
  66    low_minuend, high_subtrahend, low_subtrahend) subtracts two
  67    two-word unsigned integers, composed by HIGH_MINUEND_1 and
  68    LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and LOW_SUBTRAHEND_2
  69    respectively.  The result is placed in HIGH_DIFFERENCE and
  70    LOW_DIFFERENCE.  Overflow (i.e. carry out) is not stored anywhere,
  71    and is lost.
  72
  73    If any of these macros are left undefined for a particular CPU,
  74    C macros are used.  */
  75
  76 #if defined (__arm__)
  77 #define add_ssaaaa(sh, sl, ah, al, bh, bl) \
  78   __asm__ ("adds        %1, %4, %5                                      \n\
  79         adc     %0, %2, %3"                                             \
  80            : "=r" ((USItype) (sh)),                                     \
  81              "=&r" ((USItype) (sl))                                     \
  82            : "%r" ((USItype) (ah)),                                     \
  83              "rI" ((USItype) (bh)),                                     \
  84              "%r" ((USItype) (al)),                                     \
  85              "rI" ((USItype) (bl)))
  86 #define sub_ddmmss(sh, sl, ah, al, bh, bl) \
  87   __asm__ ("subs        %1, %4, %5                                      \n\
  88         sbc     %0, %2, %3"                                             \
  89            : "=r" ((USItype) (sh)),                                     \
  90              "=&r" ((USItype) (sl))                                     \
  91            : "r" ((USItype) (ah)),                                      \
  92              "rI" ((USItype) (bh)),                                     \
  93              "r" ((USItype) (al)),                                      \
  94              "rI" ((USItype) (bl)))
  95 #define umul_ppmm(xh, xl, a, b) \
  96 {register USItype __t0, __t1, __t2;                                     \
  97   __asm__ ("%@ Inlined umul_ppmm                                        \n\
  98         mov     %2, %5, lsr #16                                         \n\
  99         mov     %0, %6, lsr #16                                         \n\
 100         bic     %3, %5, %2, lsl #16                                     \n\
 101         bic     %4, %6, %0, lsl #16                                     \n\
 102         mul     %1, %3, %4                                              \n\
 103         mul     %4, %2, %4                                              \n\
 104         mul     %3, %0, %3                                              \n\
 105         mul     %0, %2, %0                                              \n\
 106         adds    %3, %4, %3                                              \n\
 107         addcs   %0, %0, #65536                                          \n\
 108         adds    %1, %1, %3, lsl #16                                     \n\
 109         adc     %0, %0, %3, lsr #16"                                    \
 110            : "=&r" ((USItype) (xh)),                                    \
 111              "=r" ((USItype) (xl)),                                     \
 112              "=&r" (__t0), "=&r" (__t1), "=r" (__t2)                    \
 113            : "r" ((USItype) (a)),                                       \
 114              "r" ((USItype) (b)));}
 115 #define UMUL_TIME 20
 116 #define UDIV_TIME 100
 117 #endif /* __arm__ */
 118
 119 #define __umulsidi3(u, v) \
 120   ({DIunion __w;                                                        \
 121     umul_ppmm (__w.s.high, __w.s.low, u, v);                            \
 122     __w.ll; })
 123
 124 #define __udiv_qrnnd_c(q, r, n1, n0, d) \
 125   do {                                                                  \
 126     USItype __d1, __d0, __q1, __q0;                                     \
 127     USItype __r1, __r0, __m;                                            \
 128     __d1 = __ll_highpart (d);                                           \
 129     __d0 = __ll_lowpart (d);                                            \
 130                                                                         \
 131     __r1 = (n1) % __d1;                                                 \
 132     __q1 = (n1) / __d1;                                                 \
 133     __m = (USItype) __q1 * __d0;                                        \
 134     __r1 = __r1 * __ll_B | __ll_highpart (n0);                          \
 135     if (__r1 < __m)                                                     \
 136       {                                                                 \
 137         __q1--, __r1 += (d);                                            \
 138         if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
 139           if (__r1 < __m)                                               \
 140             __q1--, __r1 += (d);                                        \
 141       }                                                                 \
 142     __r1 -= __m;                                                        \
 143                                                                         \
 144     __r0 = __r1 % __d1;                                                 \
 145     __q0 = __r1 / __d1;                                                 \
 146     __m = (USItype) __q0 * __d0;                                        \
 147     __r0 = __r0 * __ll_B | __ll_lowpart (n0);                           \
 148     if (__r0 < __m)                                                     \
 149       {                                                                 \
 150         __q0--, __r0 += (d);                                            \
 151         if (__r0 >= (d))                                                \
 152           if (__r0 < __m)                                               \
 153             __q0--, __r0 += (d);                                        \
 154       }                                                                 \
 155     __r0 -= __m;                                                        \
 156                                                                         \
 157     (q) = (USItype) __q1 * __ll_B | __q0;                               \
 158     (r) = __r0;                                                         \
 159   } while (0)
 160
 161 #define UDIV_NEEDS_NORMALIZATION 1
 162 #define udiv_qrnnd __udiv_qrnnd_c
 163
 164 extern const UQItype __clz_tab[];
 165 #define count_leading_zeros(count, x) \
 166   do {                                                                  \
 167     USItype __xr = (x);                                                 \
 168     USItype __a;                                                        \
 169                                                                         \
 170     if (SI_TYPE_SIZE <= 32)                                             \
 171       {                                                                 \
 172         __a = __xr < ((USItype)1<<2*__BITS4)                            \
 173           ? (__xr < ((USItype)1<<__BITS4) ? 0 : __BITS4)                \
 174           : (__xr < ((USItype)1<<3*__BITS4) ?  2*__BITS4 : 3*__BITS4);  \
 175       }                                                                 \
 176     else                                                                \
 177       {                                                                 \
 178         for (__a = SI_TYPE_SIZE - 8; __a > 0; __a -= 8)                 \
 179           if (((__xr >> __a) & 0xff) != 0)                              \
 180             break;                                                      \
 181       }                                                                 \
 182                                                                         \
 183     (count) = SI_TYPE_SIZE - (__clz_tab[__xr >> __a] + __a);            \
 184   } while (0)