arch/nios2/lib/longlong.h

   1 /* longlong.h -- definitions for mixed size 32/64 bit arithmetic.
   2    Copyright (C) 1991, 1992, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2004,
   3    2005  Free Software Foundation, Inc.
   4
   5    This definition file is free software; you can redistribute it
   6    and/or modify it under the terms of the GNU General Public
   7    License as published by the Free Software Foundation; either
   8    version 2, or (at your option) any later version.
   9
  10    This definition file is distributed in the hope that it will be
  11    useful, but WITHOUT ANY WARRANTY; without even the implied
  12    warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  13    See the GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program; if not, write to the Free Software
  17    Foundation, Inc., 51 Franklin Street, Fifth Floor,
  18    Boston, MA 02110-1301, USA.  */
  19
  20 /* You have to define the following before including this file:
  21
  22    UWtype -- An unsigned type, default type for operations (typically a "word")
  23    UHWtype -- An unsigned type, at least half the size of UWtype.
  24    UDWtype -- An unsigned type, at least twice as large a UWtype
  25    W_TYPE_SIZE -- size in bits of UWtype
  26
  27    UQItype -- Unsigned 8 bit type.
  28    SItype, USItype -- Signed and unsigned 32 bit types.
  29    DItype, UDItype -- Signed and unsigned 64 bit types.
  30
  31    On a 32 bit machine UWtype should typically be USItype;
  32    on a 64 bit machine, UWtype should typically be UDItype.  */
  33
  34 #define __BITS4 (W_TYPE_SIZE / 4)
  35 #define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
  36 #define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
  37 #define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
  38
  39 #ifndef W_TYPE_SIZE
  40 #define W_TYPE_SIZE     32
  41 #define UWtype          USItype
  42 #define UHWtype         USItype
  43 #define UDWtype         UDItype
  44 #endif
  45
  46 extern const UQItype __clz_tab[256];
  47
  48 /* Define auxiliary asm macros.
  49
  50    1) umul_ppmm(high_prod, low_prod, multiplier, multiplicand) multiplies two
  51    UWtype integers MULTIPLIER and MULTIPLICAND, and generates a two UWtype
  52    word product in HIGH_PROD and LOW_PROD.
  53
  54    2) __umulsidi3(a,b) multiplies two UWtype integers A and B, and returns a
  55    UDWtype product.  This is just a variant of umul_ppmm.
  56
  57    3) udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
  58    denominator) divides a UDWtype, composed by the UWtype integers
  59    HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and places the quotient
  60    in QUOTIENT and the remainder in REMAINDER.  HIGH_NUMERATOR must be less
  61    than DENOMINATOR for correct operation.  If, in addition, the most
  62    significant bit of DENOMINATOR must be 1, then the pre-processor symbol
  63    UDIV_NEEDS_NORMALIZATION is defined to 1.
  64
  65    4) sdiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
  66    denominator).  Like udiv_qrnnd but the numbers are signed.  The quotient
  67    is rounded towards 0.
  68
  69    5) count_leading_zeros(count, x) counts the number of zero-bits from the
  70    msb to the first nonzero bit in the UWtype X.  This is the number of
  71    steps X needs to be shifted left to set the msb.  Undefined for X == 0,
  72    unless the symbol COUNT_LEADING_ZEROS_0 is defined to some value.
  73
  74    6) count_trailing_zeros(count, x) like count_leading_zeros, but counts
  75    from the least significant end.
  76
  77    7) add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,
  78    high_addend_2, low_addend_2) adds two UWtype integers, composed by
  79    HIGH_ADDEND_1 and LOW_ADDEND_1, and HIGH_ADDEND_2 and LOW_ADDEND_2
  80    respectively.  The result is placed in HIGH_SUM and LOW_SUM.  Overflow
  81    (i.e. carry out) is not stored anywhere, and is lost.
  82
  83    8) sub_ddmmss(high_difference, low_difference, high_minuend, low_minuend,
  84    high_subtrahend, low_subtrahend) subtracts two two-word UWtype integers,
  85    composed by HIGH_MINUEND_1 and LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and
  86    LOW_SUBTRAHEND_2 respectively.  The result is placed in HIGH_DIFFERENCE
  87    and LOW_DIFFERENCE.  Overflow (i.e. carry out) is not stored anywhere,
  88    and is lost.
  89
  90    If any of these macros are left undefined for a particular CPU,
  91    C macros are used.  */
  92
  93 /* The CPUs come in alphabetical order below.
  94
  95    Please add support for more CPUs here, or improve the current support
  96    for the CPUs below!
  97    (E.g. WE32100, IBM360.)  */
  98
  99 /* Snipped per CPU support */
 100
 101 /* If this machine has no inline assembler, use C macros.  */
 102
 103 #if !defined (add_ssaaaa)
 104 #define add_ssaaaa(sh, sl, ah, al, bh, bl) \
 105   do {                                                                  \
 106     UWtype __x;                                                         \
 107     __x = (al) + (bl);                                                  \
 108     (sh) = (ah) + (bh) + (__x < (al));                                  \
 109     (sl) = __x;                                                         \
 110   } while (0)
 111 #endif
 112
 113 #if !defined (sub_ddmmss)
 114 #define sub_ddmmss(sh, sl, ah, al, bh, bl) \
 115   do {                                                                  \
 116     UWtype __x;                                                         \
 117     __x = (al) - (bl);                                                  \
 118     (sh) = (ah) - (bh) - (__x > (al));                                  \
 119     (sl) = __x;                                                         \
 120   } while (0)
 121 #endif
 122
 123 /* If we lack umul_ppmm but have smul_ppmm, define umul_ppmm in terms of
 124    smul_ppmm.  */
 125 #if !defined (umul_ppmm) && defined (smul_ppmm)
 126 #define umul_ppmm(w1, w0, u, v)                                         \
 127   do {                                                                  \
 128     UWtype __w1;                                                        \
 129     UWtype __xm0 = (u), __xm1 = (v);                                    \
 130     smul_ppmm (__w1, w0, __xm0, __xm1);                                 \
 131     (w1) = __w1 + (-(__xm0 >> (W_TYPE_SIZE - 1)) & __xm1)               \
 132                 + (-(__xm1 >> (W_TYPE_SIZE - 1)) & __xm0);              \
 133   } while (0)
 134 #endif
 135
 136 /* If we still don't have umul_ppmm, define it using plain C.  */
 137 #if !defined (umul_ppmm)
 138 #define umul_ppmm(w1, w0, u, v)                                         \
 139   do {                                                                  \
 140     UWtype __x0, __x1, __x2, __x3;                                      \
 141     UHWtype __ul, __vl, __uh, __vh;                                     \
 142                                                                         \
 143     __ul = __ll_lowpart (u);                                            \
 144     __uh = __ll_highpart (u);                                           \
 145     __vl = __ll_lowpart (v);                                            \
 146     __vh = __ll_highpart (v);                                           \
 147                                                                         \
 148     __x0 = (UWtype) __ul * __vl;                                        \
 149     __x1 = (UWtype) __ul * __vh;                                        \
 150     __x2 = (UWtype) __uh * __vl;                                        \
 151     __x3 = (UWtype) __uh * __vh;                                        \
 152                                                                         \
 153     __x1 += __ll_highpart (__x0);/* this can't give carry */            \
 154     __x1 += __x2;               /* but this indeed can */               \
 155     if (__x1 < __x2)            /* did we get it? */                    \
 156       __x3 += __ll_B;           /* yes, add it in the proper pos.  */   \
 157                                                                         \
 158     (w1) = __x3 + __ll_highpart (__x1);                                 \
 159     (w0) = __ll_lowpart (__x1) * __ll_B + __ll_lowpart (__x0);          \
 160   } while (0)
 161 #endif
 162
 163 #if !defined (__umulsidi3)
 164 #define __umulsidi3(u, v) \
 165   ({DWunion __w;                                                        \
 166     umul_ppmm (__w.s.high, __w.s.low, u, v);                            \
 167     __w.ll; })
 168 #endif
 169
 170 /* Define this unconditionally, so it can be used for debugging.  */
 171 #define __udiv_qrnnd_c(q, r, n1, n0, d) \
 172   do {                                                                  \
 173     UWtype __d1, __d0, __q1, __q0;                                      \
 174     UWtype __r1, __r0, __m;                                             \
 175     __d1 = __ll_highpart (d);                                           \
 176     __d0 = __ll_lowpart (d);                                            \
 177                                                                         \
 178     __r1 = (n1) % __d1;                                                 \
 179     __q1 = (n1) / __d1;                                                 \
 180     __m = (UWtype) __q1 * __d0;                                         \
 181     __r1 = __r1 * __ll_B | __ll_highpart (n0);                          \
 182     if (__r1 < __m)                                                     \
 183       {                                                                 \
 184         __q1--, __r1 += (d);                                            \
 185         if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
 186           if (__r1 < __m)                                               \
 187             __q1--, __r1 += (d);                                        \
 188       }                                                                 \
 189     __r1 -= __m;                                                        \
 190                                                                         \
 191     __r0 = __r1 % __d1;                                                 \
 192     __q0 = __r1 / __d1;                                                 \
 193     __m = (UWtype) __q0 * __d0;                                         \
 194     __r0 = __r0 * __ll_B | __ll_lowpart (n0);                           \
 195     if (__r0 < __m)                                                     \
 196       {                                                                 \
 197         __q0--, __r0 += (d);                                            \
 198         if (__r0 >= (d))                                                \
 199           if (__r0 < __m)                                               \
 200             __q0--, __r0 += (d);                                        \
 201       }                                                                 \
 202     __r0 -= __m;                                                        \
 203                                                                         \
 204     (q) = (UWtype) __q1 * __ll_B | __q0;                                \
 205     (r) = __r0;                                                         \
 206   } while (0)
 207
 208 /* If the processor has no udiv_qrnnd but sdiv_qrnnd, go through
 209    __udiv_w_sdiv (defined in libgcc or elsewhere).  */
 210 #if !defined (udiv_qrnnd) && defined (sdiv_qrnnd)
 211 #define udiv_qrnnd(q, r, nh, nl, d) \
 212   do {                                                                  \
 213     USItype __r;                                                        \
 214     (q) = __udiv_w_sdiv (&__r, nh, nl, d);                              \
 215     (r) = __r;                                                          \
 216   } while (0)
 217 #endif
 218
 219 /* If udiv_qrnnd was not defined for this processor, use __udiv_qrnnd_c.  */
 220 #if !defined (udiv_qrnnd)
 221 #define UDIV_NEEDS_NORMALIZATION 1
 222 #define udiv_qrnnd __udiv_qrnnd_c
 223 #endif
 224
 225 #if !defined (count_leading_zeros)
 226 #define count_leading_zeros(count, x) \
 227   do {                                                                  \
 228     UWtype __xr = (x);                                                  \
 229     UWtype __a;                                                         \
 230                                                                         \
 231     if (W_TYPE_SIZE <= 32)                                              \
 232       {                                                                 \
 233         __a = __xr < ((UWtype)1<<2*__BITS4)                             \
 234           ? (__xr < ((UWtype)1<<__BITS4) ? 0 : __BITS4)                 \
 235           : (__xr < ((UWtype)1<<3*__BITS4) ?  2*__BITS4 : 3*__BITS4);   \
 236       }                                                                 \
 237     else                                                                \
 238       {                                                                 \
 239         for (__a = W_TYPE_SIZE - 8; __a > 0; __a -= 8)                  \
 240           if (((__xr >> __a) & 0xff) != 0)                              \
 241             break;                                                      \
 242       }                                                                 \
 243                                                                         \
 244     (count) = W_TYPE_SIZE - (__clz_tab[__xr >> __a] + __a);             \
 245   } while (0)
 246 #define COUNT_LEADING_ZEROS_0 W_TYPE_SIZE
 247 #endif
 248
 249 #if !defined (count_trailing_zeros)
 250 /* Define count_trailing_zeros using count_leading_zeros.  The latter might be
 251    defined in asm, but if it is not, the C version above is good enough.  */
 252 #define count_trailing_zeros(count, x) \
 253   do {                                                                  \
 254     UWtype __ctz_x = (x);                                               \
 255     UWtype __ctz_c;                                                     \
 256     count_leading_zeros (__ctz_c, __ctz_x & -__ctz_x);                  \
 257     (count) = W_TYPE_SIZE - 1 - __ctz_c;                                \
 258   } while (0)
 259 #endif
 260
 261 #ifndef UDIV_NEEDS_NORMALIZATION
 262 #define UDIV_NEEDS_NORMALIZATION 0
 263 #endif