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  * SPDX-License-Identifier:     GPL-2.0+
   6
   7 /* You have to define the following before including this file:
   8
   9    UWtype -- An unsigned type, default type for operations (typically a "word")
  10    UHWtype -- An unsigned type, at least half the size of UWtype.
  11    UDWtype -- An unsigned type, at least twice as large a UWtype
  12    W_TYPE_SIZE -- size in bits of UWtype
  13
  14    UQItype -- Unsigned 8 bit type.
  15    SItype, USItype -- Signed and unsigned 32 bit types.
  16    DItype, UDItype -- Signed and unsigned 64 bit types.
  17
  18    On a 32 bit machine UWtype should typically be USItype;
  19    on a 64 bit machine, UWtype should typically be UDItype.  */
  20
  21 #define __BITS4 (W_TYPE_SIZE / 4)
  22 #define __ll_B ((UWtype) 1 << (W_TYPE_SIZE / 2))
  23 #define __ll_lowpart(t) ((UWtype) (t) & (__ll_B - 1))
  24 #define __ll_highpart(t) ((UWtype) (t) >> (W_TYPE_SIZE / 2))
  25
  26 #ifndef W_TYPE_SIZE
  27 #define W_TYPE_SIZE     32
  28 #define UWtype          USItype
  29 #define UHWtype         USItype
  30 #define UDWtype         UDItype
  31 #endif
  32
  33 extern const UQItype __clz_tab[256];
  34
  35 /* Define auxiliary asm macros.
  36
  37    1) umul_ppmm(high_prod, low_prod, multiplier, multiplicand) multiplies two
  38    UWtype integers MULTIPLIER and MULTIPLICAND, and generates a two UWtype
  39    word product in HIGH_PROD and LOW_PROD.
  40
  41    2) __umulsidi3(a,b) multiplies two UWtype integers A and B, and returns a
  42    UDWtype product.  This is just a variant of umul_ppmm.
  43
  44    3) udiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
  45    denominator) divides a UDWtype, composed by the UWtype integers
  46    HIGH_NUMERATOR and LOW_NUMERATOR, by DENOMINATOR and places the quotient
  47    in QUOTIENT and the remainder in REMAINDER.  HIGH_NUMERATOR must be less
  48    than DENOMINATOR for correct operation.  If, in addition, the most
  49    significant bit of DENOMINATOR must be 1, then the pre-processor symbol
  50    UDIV_NEEDS_NORMALIZATION is defined to 1.
  51
  52    4) sdiv_qrnnd(quotient, remainder, high_numerator, low_numerator,
  53    denominator).  Like udiv_qrnnd but the numbers are signed.  The quotient
  54    is rounded towards 0.
  55
  56    5) count_leading_zeros(count, x) counts the number of zero-bits from the
  57    msb to the first nonzero bit in the UWtype X.  This is the number of
  58    steps X needs to be shifted left to set the msb.  Undefined for X == 0,
  59    unless the symbol COUNT_LEADING_ZEROS_0 is defined to some value.
  60
  61    6) count_trailing_zeros(count, x) like count_leading_zeros, but counts
  62    from the least significant end.
  63
  64    7) add_ssaaaa(high_sum, low_sum, high_addend_1, low_addend_1,
  65    high_addend_2, low_addend_2) adds two UWtype integers, composed by
  66    HIGH_ADDEND_1 and LOW_ADDEND_1, and HIGH_ADDEND_2 and LOW_ADDEND_2
  67    respectively.  The result is placed in HIGH_SUM and LOW_SUM.  Overflow
  68    (i.e. carry out) is not stored anywhere, and is lost.
  69
  70    8) sub_ddmmss(high_difference, low_difference, high_minuend, low_minuend,
  71    high_subtrahend, low_subtrahend) subtracts two two-word UWtype integers,
  72    composed by HIGH_MINUEND_1 and LOW_MINUEND_1, and HIGH_SUBTRAHEND_2 and
  73    LOW_SUBTRAHEND_2 respectively.  The result is placed in HIGH_DIFFERENCE
  74    and LOW_DIFFERENCE.  Overflow (i.e. carry out) is not stored anywhere,
  75    and is lost.
  76
  77    If any of these macros are left undefined for a particular CPU,
  78    C macros are used.  */
  79
  80 /* The CPUs come in alphabetical order below.
  81
  82    Please add support for more CPUs here, or improve the current support
  83    for the CPUs below!
  84    (E.g. WE32100, IBM360.)  */
  85
  86 /* Snipped per CPU support */
  87
  88 /* If this machine has no inline assembler, use C macros.  */
  89
  90 #if !defined (add_ssaaaa)
  91 #define add_ssaaaa(sh, sl, ah, al, bh, bl) \
  92   do {                                                                  \
  93     UWtype __x;                                                         \
  94     __x = (al) + (bl);                                                  \
  95     (sh) = (ah) + (bh) + (__x < (al));                                  \
  96     (sl) = __x;                                                         \
  97   } while (0)
  98 #endif
  99
 100 #if !defined (sub_ddmmss)
 101 #define sub_ddmmss(sh, sl, ah, al, bh, bl) \
 102   do {                                                                  \
 103     UWtype __x;                                                         \
 104     __x = (al) - (bl);                                                  \
 105     (sh) = (ah) - (bh) - (__x > (al));                                  \
 106     (sl) = __x;                                                         \
 107   } while (0)
 108 #endif
 109
 110 /* If we lack umul_ppmm but have smul_ppmm, define umul_ppmm in terms of
 111    smul_ppmm.  */
 112 #if !defined (umul_ppmm) && defined (smul_ppmm)
 113 #define umul_ppmm(w1, w0, u, v)                                         \
 114   do {                                                                  \
 115     UWtype __w1;                                                        \
 116     UWtype __xm0 = (u), __xm1 = (v);                                    \
 117     smul_ppmm (__w1, w0, __xm0, __xm1);                                 \
 118     (w1) = __w1 + (-(__xm0 >> (W_TYPE_SIZE - 1)) & __xm1)               \
 119                 + (-(__xm1 >> (W_TYPE_SIZE - 1)) & __xm0);              \
 120   } while (0)
 121 #endif
 122
 123 /* If we still don't have umul_ppmm, define it using plain C.  */
 124 #if !defined (umul_ppmm)
 125 #define umul_ppmm(w1, w0, u, v)                                         \
 126   do {                                                                  \
 127     UWtype __x0, __x1, __x2, __x3;                                      \
 128     UHWtype __ul, __vl, __uh, __vh;                                     \
 129                                                                         \
 130     __ul = __ll_lowpart (u);                                            \
 131     __uh = __ll_highpart (u);                                           \
 132     __vl = __ll_lowpart (v);                                            \
 133     __vh = __ll_highpart (v);                                           \
 134                                                                         \
 135     __x0 = (UWtype) __ul * __vl;                                        \
 136     __x1 = (UWtype) __ul * __vh;                                        \
 137     __x2 = (UWtype) __uh * __vl;                                        \
 138     __x3 = (UWtype) __uh * __vh;                                        \
 139                                                                         \
 140     __x1 += __ll_highpart (__x0);/* this can't give carry */            \
 141     __x1 += __x2;               /* but this indeed can */               \
 142     if (__x1 < __x2)            /* did we get it? */                    \
 143       __x3 += __ll_B;           /* yes, add it in the proper pos.  */   \
 144                                                                         \
 145     (w1) = __x3 + __ll_highpart (__x1);                                 \
 146     (w0) = __ll_lowpart (__x1) * __ll_B + __ll_lowpart (__x0);          \
 147   } while (0)
 148 #endif
 149
 150 #if !defined (__umulsidi3)
 151 #define __umulsidi3(u, v) \
 152   ({DWunion __w;                                                        \
 153     umul_ppmm (__w.s.high, __w.s.low, u, v);                            \
 154     __w.ll; })
 155 #endif
 156
 157 /* Define this unconditionally, so it can be used for debugging.  */
 158 #define __udiv_qrnnd_c(q, r, n1, n0, d) \
 159   do {                                                                  \
 160     UWtype __d1, __d0, __q1, __q0;                                      \
 161     UWtype __r1, __r0, __m;                                             \
 162     __d1 = __ll_highpart (d);                                           \
 163     __d0 = __ll_lowpart (d);                                            \
 164                                                                         \
 165     __r1 = (n1) % __d1;                                                 \
 166     __q1 = (n1) / __d1;                                                 \
 167     __m = (UWtype) __q1 * __d0;                                         \
 168     __r1 = __r1 * __ll_B | __ll_highpart (n0);                          \
 169     if (__r1 < __m)                                                     \
 170       {                                                                 \
 171         __q1--, __r1 += (d);                                            \
 172         if (__r1 >= (d)) /* i.e. we didn't get carry when adding to __r1 */\
 173           if (__r1 < __m)                                               \
 174             __q1--, __r1 += (d);                                        \
 175       }                                                                 \
 176     __r1 -= __m;                                                        \
 177                                                                         \
 178     __r0 = __r1 % __d1;                                                 \
 179     __q0 = __r1 / __d1;                                                 \
 180     __m = (UWtype) __q0 * __d0;                                         \
 181     __r0 = __r0 * __ll_B | __ll_lowpart (n0);                           \
 182     if (__r0 < __m)                                                     \
 183       {                                                                 \
 184         __q0--, __r0 += (d);                                            \
 185         if (__r0 >= (d))                                                \
 186           if (__r0 < __m)                                               \
 187             __q0--, __r0 += (d);                                        \
 188       }                                                                 \
 189     __r0 -= __m;                                                        \
 190                                                                         \
 191     (q) = (UWtype) __q1 * __ll_B | __q0;                                \
 192     (r) = __r0;                                                         \
 193   } while (0)
 194
 195 /* If the processor has no udiv_qrnnd but sdiv_qrnnd, go through
 196    __udiv_w_sdiv (defined in libgcc or elsewhere).  */
 197 #if !defined (udiv_qrnnd) && defined (sdiv_qrnnd)
 198 #define udiv_qrnnd(q, r, nh, nl, d) \
 199   do {                                                                  \
 200     USItype __r;                                                        \
 201     (q) = __udiv_w_sdiv (&__r, nh, nl, d);                              \
 202     (r) = __r;                                                          \
 203   } while (0)
 204 #endif
 205
 206 /* If udiv_qrnnd was not defined for this processor, use __udiv_qrnnd_c.  */
 207 #if !defined (udiv_qrnnd)
 208 #define UDIV_NEEDS_NORMALIZATION 1
 209 #define udiv_qrnnd __udiv_qrnnd_c
 210 #endif
 211
 212 #if !defined (count_leading_zeros)
 213 #define count_leading_zeros(count, x) \
 214   do {                                                                  \
 215     UWtype __xr = (x);                                                  \
 216     UWtype __a;                                                         \
 217                                                                         \
 218     if (W_TYPE_SIZE <= 32)                                              \
 219       {                                                                 \
 220         __a = __xr < ((UWtype)1<<2*__BITS4)                             \
 221           ? (__xr < ((UWtype)1<<__BITS4) ? 0 : __BITS4)                 \
 222           : (__xr < ((UWtype)1<<3*__BITS4) ?  2*__BITS4 : 3*__BITS4);   \
 223       }                                                                 \
 224     else                                                                \
 225       {                                                                 \
 226         for (__a = W_TYPE_SIZE - 8; __a > 0; __a -= 8)                  \
 227           if (((__xr >> __a) & 0xff) != 0)                              \
 228             break;                                                      \
 229       }                                                                 \
 230                                                                         \
 231     (count) = W_TYPE_SIZE - (__clz_tab[__xr >> __a] + __a);             \
 232   } while (0)
 233 #define COUNT_LEADING_ZEROS_0 W_TYPE_SIZE
 234 #endif
 235
 236 #if !defined (count_trailing_zeros)
 237 /* Define count_trailing_zeros using count_leading_zeros.  The latter might be
 238    defined in asm, but if it is not, the C version above is good enough.  */
 239 #define count_trailing_zeros(count, x) \
 240   do {                                                                  \
 241     UWtype __ctz_x = (x);                                               \
 242     UWtype __ctz_c;                                                     \
 243     count_leading_zeros (__ctz_c, __ctz_x & -__ctz_x);                  \
 244     (count) = W_TYPE_SIZE - 1 - __ctz_c;                                \
 245   } while (0)
 246 #endif
 247
 248 #ifndef UDIV_NEEDS_NORMALIZATION
 249 #define UDIV_NEEDS_NORMALIZATION 0
 250 #endif