linux/arch/parisc/math-emu/cnv_float.h
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   1/*
   2 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
   3 *
   4 * Floating-point emulation code
   5 *  Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
   6 *
   7 *    This program is free software; you can redistribute it and/or modify
   8 *    it under the terms of the GNU General Public License as published by
   9 *    the Free Software Foundation; either version 2, or (at your option)
  10 *    any later version.
  11 *
  12 *    This program is distributed in the hope that it will be useful,
  13 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *    GNU General Public License for more details.
  16 *
  17 *    You should have received a copy of the GNU General Public License
  18 *    along with this program; if not, write to the Free Software
  19 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20 */
  21
  22#ifdef __NO_PA_HDRS
  23    PA header file -- do not include this header file for non-PA builds.
  24#endif
  25
  26/*
  27 * Some more constants
  28 */
  29#define SGL_FX_MAX_EXP 30
  30#define DBL_FX_MAX_EXP 62
  31#define QUAD_FX_MAX_EXP 126
  32
  33#define Dintp1(object) (object)
  34#define Dintp2(object) (object)
  35
  36#define Duintp1(object) (object)
  37#define Duintp2(object) (object)
  38
  39#define Qintp0(object) (object)
  40#define Qintp1(object) (object)
  41#define Qintp2(object) (object)
  42#define Qintp3(object) (object)
  43
  44
  45/*
  46 * These macros will be used specifically by the convert instructions.
  47 *
  48 *
  49 * Single format macros
  50 */
  51
  52#define Sgl_to_dbl_exponent(src_exponent,dest)                  \
  53    Deposit_dexponent(dest,src_exponent+(DBL_BIAS-SGL_BIAS))
  54
  55#define Sgl_to_dbl_mantissa(src_mantissa,destA,destB)   \
  56    Deposit_dmantissap1(destA,src_mantissa>>3);         \
  57    Dmantissap2(destB) = src_mantissa << 29
  58
  59#define Sgl_isinexact_to_fix(sgl_value,exponent)        \
  60    ((exponent < (SGL_P - 1)) ?                         \
  61     (Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) : FALSE)
  62
  63#define Int_isinexact_to_sgl(int_value) (int_value << 33 - SGL_EXP_LENGTH)
  64
  65#define Sgl_roundnearest_from_int(int_value,sgl_value)                  \
  66    if (int_value & 1<<(SGL_EXP_LENGTH - 2))   /* round bit */          \
  67        if ((int_value << 34 - SGL_EXP_LENGTH) || Slow(sgl_value))      \
  68                Sall(sgl_value)++
  69
  70#define Dint_isinexact_to_sgl(dint_valueA,dint_valueB)          \
  71    ((Dintp1(dint_valueA) << 33 - SGL_EXP_LENGTH) || Dintp2(dint_valueB))
  72
  73#define Sgl_roundnearest_from_dint(dint_valueA,dint_valueB,sgl_value)   \
  74    if (Dintp1(dint_valueA) & 1<<(SGL_EXP_LENGTH - 2))                  \
  75        if ((Dintp1(dint_valueA) << 34 - SGL_EXP_LENGTH) ||             \
  76        Dintp2(dint_valueB) || Slow(sgl_value)) Sall(sgl_value)++
  77
  78#define Dint_isinexact_to_dbl(dint_value)       \
  79    (Dintp2(dint_value) << 33 - DBL_EXP_LENGTH)
  80
  81#define Dbl_roundnearest_from_dint(dint_opndB,dbl_opndA,dbl_opndB)      \
  82    if (Dintp2(dint_opndB) & 1<<(DBL_EXP_LENGTH - 2))                   \
  83       if ((Dintp2(dint_opndB) << 34 - DBL_EXP_LENGTH) || Dlowp2(dbl_opndB))  \
  84          if ((++Dallp2(dbl_opndB))==0) Dallp1(dbl_opndA)++
  85
  86#define Sgl_isone_roundbit(sgl_value,exponent)                  \
  87    ((Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) >> 31)
  88
  89#define Sgl_isone_stickybit(sgl_value,exponent)         \
  90    (exponent < (SGL_P - 2) ?                           \
  91     Sall(sgl_value) << (SGL_EXP_LENGTH + 2 + exponent) : FALSE)
  92
  93
  94/* 
  95 * Double format macros
  96 */
  97
  98#define Dbl_to_sgl_exponent(src_exponent,dest)                  \
  99    dest = src_exponent + (SGL_BIAS - DBL_BIAS)
 100
 101#define Dbl_to_sgl_mantissa(srcA,srcB,dest,inexact,guard,sticky,odd)    \
 102    Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest);   \
 103    guard = Dbit3p2(srcB);                                      \
 104    sticky = Dallp2(srcB)<<4;                                   \
 105    inexact = guard | sticky;                                   \
 106    odd = Dbit2p2(srcB)
 107
 108#define Dbl_to_sgl_denormalized(srcA,srcB,exp,dest,inexact,guard,sticky,odd,tiny) \
 109    Deposit_dexponent(srcA,1);                                          \
 110    tiny = TRUE;                                                        \
 111    if (exp >= -2) {                                                    \
 112        if (exp == 0) {                                                 \
 113            inexact = Dallp2(srcB) << 3;                                \
 114            guard = inexact >> 31;                                      \
 115            sticky = inexact << 1;                                      \
 116            Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest);   \
 117            odd = dest << 31;                                           \
 118            if (inexact) {                                              \
 119                switch(Rounding_mode()) {                               \
 120                    case ROUNDPLUS:                                     \
 121                        if (Dbl_iszero_sign(srcA)) {                    \
 122                            dest++;                                     \
 123                            if (Sgl_isone_hidden(dest)) \
 124                                tiny = FALSE;                           \
 125                            dest--;                                     \
 126                        }                                               \
 127                        break;                                          \
 128                    case ROUNDMINUS:                                    \
 129                        if (Dbl_isone_sign(srcA)) {                     \
 130                            dest++;                                     \
 131                            if (Sgl_isone_hidden(dest)) \
 132                                tiny = FALSE;                           \
 133                            dest--;                                     \
 134                        }                                               \
 135                        break;                                          \
 136                    case ROUNDNEAREST:                                  \
 137                        if (guard && (sticky || odd)) {                 \
 138                            dest++;                                     \
 139                            if (Sgl_isone_hidden(dest)) \
 140                                tiny = FALSE;                           \
 141                            dest--;                                     \
 142                        }                                               \
 143                        break;                                          \
 144                }                                                       \
 145            }                                                           \
 146                /* shift right by one to get correct result */          \
 147                guard = odd;                                            \
 148                sticky = inexact;                                       \
 149                inexact |= guard;                                       \
 150                dest >>= 1;                                             \
 151                Deposit_dsign(srcA,0);                                  \
 152                Shiftdouble(Dallp1(srcA),Dallp2(srcB),30,dest);         \
 153                odd = dest << 31;                                       \
 154        }                                                               \
 155        else {                                                          \
 156            inexact = Dallp2(srcB) << (2 + exp);                        \
 157            guard = inexact >> 31;                                      \
 158            sticky = inexact << 1;                                      \
 159            Deposit_dsign(srcA,0);                                      \
 160            if (exp == -2) dest = Dallp1(srcA);                         \
 161            else Variable_shift_double(Dallp1(srcA),Dallp2(srcB),30-exp,dest); \
 162            odd = dest << 31;                                           \
 163        }                                                               \
 164    }                                                                   \
 165    else {                                                              \
 166        Deposit_dsign(srcA,0);                                          \
 167        if (exp > (1 - SGL_P)) {                                        \
 168            dest = Dallp1(srcA) >> (- 2 - exp);                         \
 169            inexact = Dallp1(srcA) << (34 + exp);                       \
 170            guard = inexact >> 31;                                      \
 171            sticky = (inexact << 1) | Dallp2(srcB);                     \
 172            inexact |= Dallp2(srcB);                                    \
 173            odd = dest << 31;                                           \
 174        }                                                               \
 175        else {                                                          \
 176            dest = 0;                                                   \
 177            inexact = Dallp1(srcA) | Dallp2(srcB);                      \
 178            if (exp == (1 - SGL_P)) {                                   \
 179                guard = Dhidden(srcA);                                  \
 180                sticky = Dmantissap1(srcA) | Dallp2(srcB);              \
 181            }                                                           \
 182            else {                                                      \
 183                guard = 0;                                              \
 184                sticky = inexact;                                       \
 185            }                                                           \
 186            odd = 0;                                                    \
 187        }                                                               \
 188    }                                                                   \
 189    exp = 0
 190
 191#define Dbl_isinexact_to_fix(dbl_valueA,dbl_valueB,exponent)            \
 192    (exponent < (DBL_P-33) ?                                            \
 193     Dallp2(dbl_valueB) || Dallp1(dbl_valueA) << (DBL_EXP_LENGTH+1+exponent) : \
 194     (exponent < (DBL_P-1) ? Dallp2(dbl_valueB) << (exponent + (33-DBL_P)) :   \
 195      FALSE))
 196
 197#define Dbl_isoverflow_to_int(exponent,dbl_valueA,dbl_valueB)           \
 198    ((exponent > SGL_FX_MAX_EXP + 1) || Dsign(dbl_valueA)==0 ||         \
 199     Dmantissap1(dbl_valueA)!=0 || (Dallp2(dbl_valueB)>>21)!=0 ) 
 200
 201#define Dbl_isone_roundbit(dbl_valueA,dbl_valueB,exponent)              \
 202    ((exponent < (DBL_P - 33) ?                                         \
 203      Dallp1(dbl_valueA) >> ((30 - DBL_EXP_LENGTH) - exponent) :        \
 204      Dallp2(dbl_valueB) >> ((DBL_P - 2) - exponent)) & 1)
 205
 206#define Dbl_isone_stickybit(dbl_valueA,dbl_valueB,exponent)             \
 207    (exponent < (DBL_P-34) ?                                            \
 208     (Dallp2(dbl_valueB) || Dallp1(dbl_valueA)<<(DBL_EXP_LENGTH+2+exponent)) : \
 209     (exponent<(DBL_P-2) ? (Dallp2(dbl_valueB) << (exponent + (34-DBL_P))) : \
 210      FALSE))
 211
 212
 213/* Int macros */
 214
 215#define Int_from_sgl_mantissa(sgl_value,exponent)       \
 216    Sall(sgl_value) =                           \
 217        (unsigned)(Sall(sgl_value) << SGL_EXP_LENGTH)>>(31 - exponent)
 218
 219#define Int_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent)   \
 220    Shiftdouble(Dallp1(dbl_valueA),Dallp2(dbl_valueB),22,Dallp1(dbl_valueA)); \
 221    if (exponent < 31) Dallp1(dbl_valueA) >>= 30 - exponent;    \
 222    else Dallp1(dbl_valueA) <<= 1
 223
 224#define Int_negate(int_value) int_value = -int_value
 225
 226
 227/* Dint macros */
 228
 229#define Dint_from_sgl_mantissa(sgl_value,exponent,dresultA,dresultB)    \
 230    {Sall(sgl_value) <<= SGL_EXP_LENGTH;  /*  left-justify  */          \
 231    if (exponent <= 31) {                                               \
 232        Dintp1(dresultA) = 0;                                           \
 233        Dintp2(dresultB) = (unsigned)Sall(sgl_value) >> (31 - exponent); \
 234    }                                                                   \
 235    else {                                                              \
 236        Dintp1(dresultA) = Sall(sgl_value) >> (63 - exponent);          \
 237        Dintp2(dresultB) = Sall(sgl_value) << (exponent - 31);          \
 238    }}
 239
 240
 241#define Dint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB) \
 242    {if (exponent < 32) {                                               \
 243        Dintp1(destA) = 0;                                              \
 244        if (exponent <= 20)                                             \
 245            Dintp2(destB) = Dallp1(dbl_valueA) >> 20-exponent;          \
 246        else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \
 247             52-exponent,Dintp2(destB));                                        \
 248    }                                                                   \
 249    else {                                                              \
 250        if (exponent <= 52) {                                           \
 251            Dintp1(destA) = Dallp1(dbl_valueA) >> 52-exponent;          \
 252            if (exponent == 52) Dintp2(destB) = Dallp2(dbl_valueB);     \
 253            else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \
 254            52-exponent,Dintp2(destB));                                 \
 255        }                                                               \
 256        else {                                                          \
 257            Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \
 258            84-exponent,Dintp1(destA));                                 \
 259            Dintp2(destB) = Dallp2(dbl_valueB) << exponent-52;          \
 260        }                                                               \
 261    }}
 262
 263#define Dint_setzero(dresultA,dresultB)         \
 264    Dintp1(dresultA) = 0;       \
 265    Dintp2(dresultB) = 0
 266
 267#define Dint_setone_sign(dresultA,dresultB)             \
 268    Dintp1(dresultA) = ~Dintp1(dresultA);               \
 269    if ((Dintp2(dresultB) = -Dintp2(dresultB)) == 0) Dintp1(dresultA)++
 270
 271#define Dint_set_minint(dresultA,dresultB)              \
 272    Dintp1(dresultA) = (unsigned int)1<<31;             \
 273    Dintp2(dresultB) = 0
 274
 275#define Dint_isone_lowp2(dresultB)  (Dintp2(dresultB) & 01)
 276
 277#define Dint_increment(dresultA,dresultB)               \
 278    if ((++Dintp2(dresultB))==0) Dintp1(dresultA)++
 279
 280#define Dint_decrement(dresultA,dresultB)               \
 281    if ((Dintp2(dresultB)--)==0) Dintp1(dresultA)--
 282
 283#define Dint_negate(dresultA,dresultB)                  \
 284    Dintp1(dresultA) = ~Dintp1(dresultA);               \
 285    if ((Dintp2(dresultB) = -Dintp2(dresultB))==0) Dintp1(dresultA)++
 286
 287#define Dint_copyfromptr(src,destA,destB) \
 288     Dintp1(destA) = src->wd0;          \
 289     Dintp2(destB) = src->wd1
 290#define Dint_copytoptr(srcA,srcB,dest)  \
 291    dest->wd0 = Dintp1(srcA);           \
 292    dest->wd1 = Dintp2(srcB)
 293
 294
 295/* other macros  */
 296
 297#define Find_ms_one_bit(value, position)        \
 298    {                                           \
 299        int var;                                \
 300        for (var=8; var >=1; var >>= 1) {       \
 301            if (value >> 32 - position)         \
 302                position -= var;                \
 303                else position += var;           \
 304        }                                       \
 305        if ((value >> 32 - position) == 0)      \
 306            position--;                         \
 307        else position -= 2;                     \
 308    }
 309
 310
 311/*
 312 * Unsigned int macros
 313 */
 314#define Duint_copyfromptr(src,destA,destB) \
 315    Dint_copyfromptr(src,destA,destB)
 316#define Duint_copytoptr(srcA,srcB,dest) \
 317    Dint_copytoptr(srcA,srcB,dest)
 318
 319#define Suint_isinexact_to_sgl(int_value) \
 320    (int_value << 32 - SGL_EXP_LENGTH)
 321
 322#define Sgl_roundnearest_from_suint(suint_value,sgl_value)              \
 323    if (suint_value & 1<<(SGL_EXP_LENGTH - 1))   /* round bit */        \
 324        if ((suint_value << 33 - SGL_EXP_LENGTH) || Slow(sgl_value))    \
 325                Sall(sgl_value)++
 326
 327#define Duint_isinexact_to_sgl(duint_valueA,duint_valueB)       \
 328    ((Duintp1(duint_valueA) << 32 - SGL_EXP_LENGTH) || Duintp2(duint_valueB))
 329
 330#define Sgl_roundnearest_from_duint(duint_valueA,duint_valueB,sgl_value) \
 331    if (Duintp1(duint_valueA) & 1<<(SGL_EXP_LENGTH - 1))                \
 332        if ((Duintp1(duint_valueA) << 33 - SGL_EXP_LENGTH) ||           \
 333        Duintp2(duint_valueB) || Slow(sgl_value)) Sall(sgl_value)++
 334
 335#define Duint_isinexact_to_dbl(duint_value)     \
 336    (Duintp2(duint_value) << 32 - DBL_EXP_LENGTH)
 337
 338#define Dbl_roundnearest_from_duint(duint_opndB,dbl_opndA,dbl_opndB)    \
 339    if (Duintp2(duint_opndB) & 1<<(DBL_EXP_LENGTH - 1))                 \
 340       if ((Duintp2(duint_opndB) << 33 - DBL_EXP_LENGTH) || Dlowp2(dbl_opndB)) \
 341          if ((++Dallp2(dbl_opndB))==0) Dallp1(dbl_opndA)++
 342
 343#define Suint_from_sgl_mantissa(src,exponent,result)    \
 344    Sall(result) = (unsigned)(Sall(src) << SGL_EXP_LENGTH)>>(31 - exponent)
 345
 346#define Sgl_isinexact_to_unsigned(sgl_value,exponent)   \
 347    Sgl_isinexact_to_fix(sgl_value,exponent)
 348
 349#define Duint_from_sgl_mantissa(sgl_value,exponent,dresultA,dresultB)   \
 350  {unsigned int val = Sall(sgl_value) << SGL_EXP_LENGTH;                \
 351    if (exponent <= 31) {                                               \
 352        Dintp1(dresultA) = 0;                                           \
 353        Dintp2(dresultB) = val >> (31 - exponent);                      \
 354    }                                                                   \
 355    else {                                                              \
 356        Dintp1(dresultA) = val >> (63 - exponent);                      \
 357        Dintp2(dresultB) = exponent <= 62 ? val << (exponent - 31) : 0; \
 358    }                                                                   \
 359  }
 360
 361#define Duint_setzero(dresultA,dresultB)        \
 362    Dint_setzero(dresultA,dresultB)
 363
 364#define Duint_increment(dresultA,dresultB) Dint_increment(dresultA,dresultB) 
 365
 366#define Duint_isone_lowp2(dresultB)  Dint_isone_lowp2(dresultB)
 367
 368#define Suint_from_dbl_mantissa(srcA,srcB,exponent,dest) \
 369    Shiftdouble(Dallp1(srcA),Dallp2(srcB),21,dest); \
 370    dest = (unsigned)dest >> 31 - exponent
 371
 372#define Dbl_isinexact_to_unsigned(dbl_valueA,dbl_valueB,exponent) \
 373    Dbl_isinexact_to_fix(dbl_valueA,dbl_valueB,exponent)
 374
 375#define Duint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB) \
 376    Dint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB) 
 377