1 /* $NetBSD: cnv_float.h,v 1.1 2002/06/05 01:04:24 fredette Exp $ */ 2 3 /* $OpenBSD: cnv_float.h,v 1.5 2001/03/29 03:58:17 mickey Exp $ */ 4 5 /* 6 * Copyright 1996 1995 by Open Software Foundation, Inc. 7 * All Rights Reserved 8 * 9 * Permission to use, copy, modify, and distribute this software and 10 * its documentation for any purpose and without fee is hereby granted, 11 * provided that the above copyright notice appears in all copies and 12 * that both the copyright notice and this permission notice appear in 13 * supporting documentation. 14 * 15 * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE 16 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 17 * FOR A PARTICULAR PURPOSE. 18 * 19 * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR 20 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM 21 * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT, 22 * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION 23 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 24 */ 25 /* 26 * pmk1.1 27 */ 28 /* 29 * (c) Copyright 1986 HEWLETT-PACKARD COMPANY 30 * 31 * To anyone who acknowledges that this file is provided "AS IS" 32 * without any express or implied warranty: 33 * permission to use, copy, modify, and distribute this file 34 * for any purpose is hereby granted without fee, provided that 35 * the above copyright notice and this notice appears in all 36 * copies, and that the name of Hewlett-Packard Company not be 37 * used in advertising or publicity pertaining to distribution 38 * of the software without specific, written prior permission. 39 * Hewlett-Packard Company makes no representations about the 40 * suitability of this software for any purpose. 41 */ 42 43 /* 44 * Some more constants 45 */ 46 #define SGL_FX_MAX_EXP 30 47 #define DBL_FX_MAX_EXP 62 48 #define QUAD_FX_MAX_EXP 126 49 50 51 #define Dintp1(object) (object) 52 #define Dintp2(object) (object) 53 54 #define Qintp0(object) (object) 55 #define Qintp1(object) (object) 56 #define Qintp2(object) (object) 57 #define Qintp3(object) (object) 58 59 60 /* 61 * These macros will be used specifically by the convert instructions. 62 * 63 * 64 * Single format macros 65 */ 66 67 #define Sgl_to_dbl_exponent(src_exponent,dest) \ 68 Deposit_dexponent(dest,src_exponent+(DBL_BIAS-SGL_BIAS)) 69 70 #define Sgl_to_dbl_mantissa(src_mantissa,destA,destB) \ 71 Deposit_dmantissap1(destA,src_mantissa>>3); \ 72 Dmantissap2(destB) = src_mantissa << 29 73 74 #define Sgl_isinexact_to_fix(sgl_value,exponent) \ 75 ((exponent < (SGL_P - 1)) ? \ 76 (Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) : FALSE) 77 78 #define Int_isinexact_to_sgl(int_value) (int_value << (33 - SGL_EXP_LENGTH)) 79 80 #define Sgl_roundnearest_from_int(int_value,sgl_value) \ 81 if (int_value & 1<<(SGL_EXP_LENGTH - 2)) /* round bit */ \ 82 if ((int_value << (34 - SGL_EXP_LENGTH)) || Slow(sgl_value)) \ 83 Sall(sgl_value)++ 84 85 #define Dint_isinexact_to_sgl(dint_valueA,dint_valueB) \ 86 ((Dintp1(dint_valueA) << (33 - SGL_EXP_LENGTH)) || Dintp2(dint_valueB)) 87 88 #define Sgl_roundnearest_from_dint(dint_valueA,dint_valueB,sgl_value) \ 89 if (Dintp1(dint_valueA) & 1<<(SGL_EXP_LENGTH - 2)) \ 90 if ((Dintp1(dint_valueA) << (34 - SGL_EXP_LENGTH)) || \ 91 Dintp2(dint_valueB) || Slow(sgl_value)) Sall(sgl_value)++ 92 93 #define Dint_isinexact_to_dbl(dint_value) \ 94 (Dintp2(dint_value) << (33 - DBL_EXP_LENGTH)) 95 96 #define Dbl_roundnearest_from_dint(dint_opndB,dbl_opndA,dbl_opndB) \ 97 if (Dintp2(dint_opndB) & 1<<(DBL_EXP_LENGTH - 2)) \ 98 if ((Dintp2(dint_opndB) << (34 -DBL_EXP_LENGTH)) || Dlowp2(dbl_opndB)) \ 99 if ((++Dallp2(dbl_opndB))==0) Dallp1(dbl_opndA)++ 100 101 #define Sgl_isone_roundbit(sgl_value,exponent) \ 102 ((Sall(sgl_value) << (SGL_EXP_LENGTH + 1 + exponent)) >> 31) 103 104 #define Sgl_isone_stickybit(sgl_value,exponent) \ 105 (exponent < (SGL_P - 2) ? \ 106 Sall(sgl_value) << (SGL_EXP_LENGTH + 2 + exponent) : FALSE) 107 108 109 /* 110 * Double format macros 111 */ 112 113 #define Dbl_to_sgl_exponent(src_exponent,dest) \ 114 dest = src_exponent + (SGL_BIAS - DBL_BIAS) 115 116 #define Dbl_to_sgl_mantissa(srcA,srcB,dest,inexact,guard,sticky,odd) \ 117 Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest); \ 118 guard = Dbit3p2(srcB); \ 119 sticky = Dallp2(srcB)<<4; \ 120 inexact = guard | sticky; \ 121 odd = Dbit2p2(srcB) 122 123 #define Dbl_to_sgl_denormalized(srcA,srcB,exp,dest,inexact,guard,sticky,odd,tiny) \ 124 Deposit_dexponent(srcA,1); \ 125 tiny = TRUE; \ 126 if (exp >= -2) { \ 127 if (exp == 0) { \ 128 inexact = Dallp2(srcB) << 3; \ 129 guard = inexact >> 31; \ 130 sticky = inexact << 1; \ 131 Shiftdouble(Dmantissap1(srcA),Dmantissap2(srcB),29,dest); \ 132 odd = dest << 31; \ 133 if (inexact) { \ 134 switch(Rounding_mode()) { \ 135 case ROUNDPLUS: \ 136 if (Dbl_iszero_sign(srcA)) { \ 137 dest++; \ 138 if (Sgl_isone_hidden(dest)) \ 139 tiny = FALSE; \ 140 dest--; \ 141 } \ 142 break; \ 143 case ROUNDMINUS: \ 144 if (Dbl_isone_sign(srcA)) { \ 145 dest++; \ 146 if (Sgl_isone_hidden(dest)) \ 147 tiny = FALSE; \ 148 dest--; \ 149 } \ 150 break; \ 151 case ROUNDNEAREST: \ 152 if (guard && (sticky || odd)) { \ 153 dest++; \ 154 if (Sgl_isone_hidden(dest)) \ 155 tiny = FALSE; \ 156 dest--; \ 157 } \ 158 break; \ 159 } \ 160 } \ 161 /* shift right by one to get correct result */ \ 162 guard = odd; \ 163 sticky = inexact; \ 164 inexact |= guard; \ 165 dest >>= 1; \ 166 Deposit_dsign(srcA,0); \ 167 Shiftdouble(Dallp1(srcA),Dallp2(srcB),30,dest); \ 168 odd = dest << 31; \ 169 } \ 170 else { \ 171 inexact = Dallp2(srcB) << (2 + exp); \ 172 guard = inexact >> 31; \ 173 sticky = inexact << 1; \ 174 Deposit_dsign(srcA,0); \ 175 if (exp == -2) dest = Dallp1(srcA); \ 176 else Variable_shift_double(Dallp1(srcA),Dallp2(srcB),30-exp,dest); \ 177 odd = dest << 31; \ 178 } \ 179 } \ 180 else { \ 181 Deposit_dsign(srcA,0); \ 182 if (exp > (1 - SGL_P)) { \ 183 dest = Dallp1(srcA) >> (- 2 - exp); \ 184 inexact = Dallp1(srcA) << (34 + exp); \ 185 guard = inexact >> 31; \ 186 sticky = (inexact << 1) | Dallp2(srcB); \ 187 inexact |= Dallp2(srcB); \ 188 odd = dest << 31; \ 189 } \ 190 else { \ 191 dest = 0; \ 192 inexact = Dallp1(srcA) | Dallp2(srcB); \ 193 if (exp == (1 - SGL_P)) { \ 194 guard = Dhidden(srcA); \ 195 sticky = Dmantissap1(srcA) | Dallp2(srcB); \ 196 } \ 197 else { \ 198 guard = 0; \ 199 sticky = inexact; \ 200 } \ 201 odd = 0; \ 202 } \ 203 } \ 204 exp = 0 205 206 #define Dbl_isinexact_to_fix(dbl_valueA,dbl_valueB,exponent) \ 207 (exponent < (DBL_P-33) ? \ 208 Dallp2(dbl_valueB) || Dallp1(dbl_valueA) << (DBL_EXP_LENGTH+1+exponent) : \ 209 (exponent < (DBL_P-1) ? Dallp2(dbl_valueB) << (exponent + (33-DBL_P)) : \ 210 FALSE)) 211 212 #define Dbl_isoverflow_to_int(exponent,dbl_valueA,dbl_valueB) \ 213 ((exponent > SGL_FX_MAX_EXP + 1) || Dsign(dbl_valueA)==0 || \ 214 Dmantissap1(dbl_valueA)!=0 || (Dallp2(dbl_valueB)>>21)!=0 ) 215 216 #define Dbl_isone_roundbit(dbl_valueA,dbl_valueB,exponent) \ 217 ((exponent < (DBL_P - 33) ? \ 218 Dallp1(dbl_valueA) >> ((30 - DBL_EXP_LENGTH) - exponent) : \ 219 Dallp2(dbl_valueB) >> ((DBL_P - 2) - exponent)) & 1) 220 221 #define Dbl_isone_stickybit(dbl_valueA,dbl_valueB,exponent) \ 222 (exponent < (DBL_P-34) ? \ 223 (Dallp2(dbl_valueB) || Dallp1(dbl_valueA)<<(DBL_EXP_LENGTH+2+exponent)) : \ 224 (exponent<(DBL_P-2) ? (Dallp2(dbl_valueB) << (exponent + (34-DBL_P))) : \ 225 FALSE)) 226 227 228 /* Int macros */ 229 230 #define Int_from_sgl_mantissa(sgl_value,exponent) \ 231 Sall(sgl_value) = \ 232 (unsigned)(Sall(sgl_value) << SGL_EXP_LENGTH)>>(31 - exponent) 233 234 #define Int_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent) \ 235 Shiftdouble(Dallp1(dbl_valueA),Dallp2(dbl_valueB),22,Dallp1(dbl_valueA)); \ 236 if (exponent < 31) Dallp1(dbl_valueA) >>= 30 - exponent; \ 237 else Dallp1(dbl_valueA) <<= 1 238 239 #define Int_negate(int_value) int_value = -int_value 240 241 242 /* Dint macros */ 243 244 #define Dint_from_sgl_mantissa(sgl_value,exponent,dresultA,dresultB) \ 245 {Sall(sgl_value) <<= SGL_EXP_LENGTH; /* left-justify */ \ 246 if (exponent <= 31) { \ 247 Dintp1(dresultA) = 0; \ 248 Dintp2(dresultB) = (unsigned)Sall(sgl_value) >> (31 - exponent); \ 249 } \ 250 else { \ 251 Dintp1(dresultA) = Sall(sgl_value) >> (63 - exponent); \ 252 Dintp2(dresultB) = Sall(sgl_value) << (exponent - 31); \ 253 }} 254 255 256 #define Dint_from_dbl_mantissa(dbl_valueA,dbl_valueB,exponent,destA,destB) \ 257 {if (exponent < 32) { \ 258 Dintp1(destA) = 0; \ 259 if (exponent <= 20) \ 260 Dintp2(destB) = Dallp1(dbl_valueA) >> (20-(exponent)); \ 261 else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \ 262 (52-(exponent)),Dintp2(destB)); \ 263 } \ 264 else { \ 265 if (exponent <= 52) { \ 266 Dintp1(destA) = Dallp1(dbl_valueA) >> (52-(exponent)); \ 267 if (exponent == 52) Dintp2(destB) = Dallp2(dbl_valueB); \ 268 else Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \ 269 52-exponent,Dintp2(destB)); \ 270 } \ 271 else { \ 272 Variable_shift_double(Dallp1(dbl_valueA),Dallp2(dbl_valueB), \ 273 84-exponent,Dintp1(destA)); \ 274 Dintp2(destB) = Dallp2(dbl_valueB) << ((exponent)-52); \ 275 } \ 276 }} 277 278 #define Dint_setzero(dresultA,dresultB) \ 279 Dintp1(dresultA) = 0; \ 280 Dintp2(dresultB) = 0 281 282 #define Dint_setone_sign(dresultA,dresultB) \ 283 Dintp1(dresultA) = ~Dintp1(dresultA); \ 284 if ((Dintp2(dresultB) = -Dintp2(dresultB)) == 0) Dintp1(dresultA)++ 285 286 #define Dint_set_minint(dresultA,dresultB) \ 287 Dintp1(dresultA) = 1<<31; \ 288 Dintp2(dresultB) = 0 289 290 #define Dint_isone_lowp2(dresultB) (Dintp2(dresultB) & 01) 291 292 #define Dint_increment(dresultA,dresultB) \ 293 if ((++Dintp2(dresultB))==0) Dintp1(dresultA)++ 294 295 #define Dint_decrement(dresultA,dresultB) \ 296 if ((Dintp2(dresultB)--)==0) Dintp1(dresultA)-- 297 298 #define Dint_negate(dresultA,dresultB) \ 299 Dintp1(dresultA) = ~Dintp1(dresultA); \ 300 if ((Dintp2(dresultB) = -Dintp2(dresultB))==0) Dintp1(dresultA)++ 301 302 #define Dint_copyfromptr(src,destA,destB) \ 303 Dintp1(destA) = src->wd0; \ 304 Dintp2(destB) = src->wd1 305 #define Dint_copytoptr(srcA,srcB,dest) \ 306 dest->wd0 = Dintp1(srcA); \ 307 dest->wd1 = Dintp2(srcB) 308 309 310 /* other macros */ 311 312 #define Find_ms_one_bit(value, position) \ 313 { \ 314 int var; \ 315 for (var=8; var >=1; var >>= 1) { \ 316 if (value >> (32 - position)) \ 317 position -= var; \ 318 else position += var; \ 319 } \ 320 if ((value >> (32 - position)) == 0) \ 321 position--; \ 322 else position -= 2; \ 323 } 324 325 /* 326 * The following 4 functions handle the assignment of a floating point 327 * number to a 32-bit integer in cases where the floating point number 328 * is too large (or small) to fit in the integer field. 329 * 330 * In all these cases, HP-UX would return an UNIMPLEMENTEDEXCEPTION 331 * resulting in a SIGFPE being sent to the process. For BSD's math 332 * library (and various other applications), this was unacceptable. 333 * As a result, we now return maxint/minint (like most other OS's) 334 * and either return an INEXACTEXCEPTION (SIGFPE) or set the inexact 335 * flag (so that the program may continue execution). 336 * 337 * After discussing this with Jerry Huck @ HP, the one case where we 338 * differ from BSD is for programs that try to convert a NaN to an 339 * integer; in this case, we will return an UNIMPLEMENTEDEXCEPTION 340 * since doing anything else would be completely unreasonable. 341 * 342 * jef 343 */ 344 345 #define Dbl_return_overflow(srcp1, srcp2, resultp) \ 346 { \ 347 if (Dbl_isnan(srcp1, srcp2)) \ 348 return(UNIMPLEMENTEDEXCEPTION); \ 349 if (Dbl_iszero_sign(srcp1)) \ 350 *resultp = 0x7fffffff; \ 351 else \ 352 *resultp = 0x80000000; \ 353 if (Is_overflowtrap_enabled()) { \ 354 if (Is_inexacttrap_enabled()) \ 355 return(OVERFLOWEXCEPTION|INEXACTEXCEPTION); \ 356 else \ 357 Set_inexactflag(); \ 358 return(OVERFLOWEXCEPTION); \ 359 } \ 360 return(NOEXCEPTION); \ 361 } 362 363 #define Dbl_return_overflow_dbl(srcp1, srcp2, resultp) \ 364 { \ 365 if (Dbl_isnan(srcp1, srcp2)) \ 366 return(UNIMPLEMENTEDEXCEPTION); \ 367 if (Dbl_iszero_sign(srcp1)) { \ 368 Dint_copytoptr(0x7fffffff,0xffffffff,resultp); \ 369 } else { \ 370 Dint_copytoptr(0x80000000,0x00000000,resultp); \ 371 } \ 372 if (Is_overflowtrap_enabled()) { \ 373 if (Is_inexacttrap_enabled()) \ 374 return(OVERFLOWEXCEPTION|INEXACTEXCEPTION); \ 375 else \ 376 Set_inexactflag(); \ 377 return(OVERFLOWEXCEPTION); \ 378 } \ 379 return(NOEXCEPTION); \ 380 } 381 382 #define Sgl_return_overflow(src, resultp) \ 383 { \ 384 if (Sgl_isnan(src)) \ 385 return(UNIMPLEMENTEDEXCEPTION); \ 386 if (Sgl_iszero_sign(src)) \ 387 *resultp = 0x7fffffff; \ 388 else \ 389 *resultp = 0x80000000; \ 390 if (Is_overflowtrap_enabled()) { \ 391 if (Is_inexacttrap_enabled()) \ 392 return(OVERFLOWEXCEPTION|INEXACTEXCEPTION); \ 393 else \ 394 Set_inexactflag(); \ 395 return(OVERFLOWEXCEPTION); \ 396 } \ 397 return(NOEXCEPTION); \ 398 } 399 400 #define Sgl_return_overflow_dbl(src, resultp) \ 401 { \ 402 if (Sgl_isnan(src)) \ 403 return(UNIMPLEMENTEDEXCEPTION); \ 404 if (Sgl_iszero_sign(src)) { \ 405 Dint_copytoptr(0x7fffffff,0xffffffff,resultp); \ 406 } else { \ 407 Dint_copytoptr(0x80000000,0x00000000,resultp); \ 408 } \ 409 if (Is_overflowtrap_enabled()) { \ 410 if (Is_inexacttrap_enabled()) \ 411 return(OVERFLOWEXCEPTION|INEXACTEXCEPTION); \ 412 else \ 413 Set_inexactflag(); \ 414 return(OVERFLOWEXCEPTION); \ 415 } \ 416 return(NOEXCEPTION); \ 417 } 418 419 int sgl_to_sgl_fcnvfx __P((sgl_floating_point *, sgl_floating_point *, unsigned int *)); 420 int sgl_to_dbl_fcnvfx __P((sgl_floating_point *, dbl_integer *, unsigned int *)); 421 int dbl_to_sgl_fcnvfx __P((dbl_floating_point *, int *, unsigned int *)); 422 int dbl_to_dbl_fcnvfx __P((dbl_floating_point *, dbl_integer *, unsigned int *)); 423 424 int sgl_to_sgl_fcnvfxt __P((sgl_floating_point *, int *, unsigned int *)); 425 int sgl_to_dbl_fcnvfxt __P((sgl_floating_point *, dbl_integer *, unsigned int *)); 426 int dbl_to_sgl_fcnvfxt __P((dbl_floating_point *, int *, unsigned int *)); 427 int dbl_to_dbl_fcnvfxt __P((dbl_floating_point *, dbl_integer *, unsigned int *)); 428 429 int sgl_to_sgl_fcnvxf __P((int *, sgl_floating_point *, unsigned int *)); 430 int sgl_to_dbl_fcnvxf __P((int *, dbl_floating_point *, unsigned int *)); 431 int dbl_to_sgl_fcnvxf __P((dbl_integer *, sgl_floating_point *, unsigned int *)); 432 int dbl_to_dbl_fcnvxf __P((dbl_integer *, dbl_floating_point *, unsigned int *)); 433 434 435 436