fcnvfxt.c (7969B)
1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * Linux/PA-RISC Project (http://www.parisc-linux.org/) 4 * 5 * Floating-point emulation code 6 * Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org> 7 */ 8/* 9 * BEGIN_DESC 10 * 11 * File: 12 * @(#) pa/spmath/fcnvfxt.c $Revision: 1.1 $ 13 * 14 * Purpose: 15 * Single Floating-point to Single Fixed-point /w truncated result 16 * Single Floating-point to Double Fixed-point /w truncated result 17 * Double Floating-point to Single Fixed-point /w truncated result 18 * Double Floating-point to Double Fixed-point /w truncated result 19 * 20 * External Interfaces: 21 * dbl_to_dbl_fcnvfxt(srcptr,nullptr,dstptr,status) 22 * dbl_to_sgl_fcnvfxt(srcptr,nullptr,dstptr,status) 23 * sgl_to_dbl_fcnvfxt(srcptr,nullptr,dstptr,status) 24 * sgl_to_sgl_fcnvfxt(srcptr,nullptr,dstptr,status) 25 * 26 * Internal Interfaces: 27 * 28 * Theory: 29 * <<please update with a overview of the operation of this file>> 30 * 31 * END_DESC 32*/ 33 34 35#include "float.h" 36#include "sgl_float.h" 37#include "dbl_float.h" 38#include "cnv_float.h" 39 40/* 41 * Convert single floating-point to single fixed-point format 42 * with truncated result 43 */ 44/*ARGSUSED*/ 45int 46sgl_to_sgl_fcnvfxt( 47 sgl_floating_point *srcptr, 48 unsigned int *nullptr, 49 int *dstptr, 50 unsigned int *status) 51{ 52 register unsigned int src, temp; 53 register int src_exponent, result; 54 55 src = *srcptr; 56 src_exponent = Sgl_exponent(src) - SGL_BIAS; 57 58 /* 59 * Test for overflow 60 */ 61 if (src_exponent > SGL_FX_MAX_EXP) { 62 /* check for MININT */ 63 if ((src_exponent > SGL_FX_MAX_EXP + 1) || 64 Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) { 65 if (Sgl_iszero_sign(src)) result = 0x7fffffff; 66 else result = 0x80000000; 67 68 if (Is_invalidtrap_enabled()) { 69 return(INVALIDEXCEPTION); 70 } 71 Set_invalidflag(); 72 *dstptr = result; 73 return(NOEXCEPTION); 74 } 75 } 76 /* 77 * Generate result 78 */ 79 if (src_exponent >= 0) { 80 temp = src; 81 Sgl_clear_signexponent_set_hidden(temp); 82 Int_from_sgl_mantissa(temp,src_exponent); 83 if (Sgl_isone_sign(src)) result = -Sgl_all(temp); 84 else result = Sgl_all(temp); 85 *dstptr = result; 86 87 /* check for inexact */ 88 if (Sgl_isinexact_to_fix(src,src_exponent)) { 89 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 90 else Set_inexactflag(); 91 } 92 } 93 else { 94 *dstptr = 0; 95 96 /* check for inexact */ 97 if (Sgl_isnotzero_exponentmantissa(src)) { 98 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 99 else Set_inexactflag(); 100 } 101 } 102 return(NOEXCEPTION); 103} 104 105/* 106 * Single Floating-point to Double Fixed-point 107 */ 108/*ARGSUSED*/ 109int 110sgl_to_dbl_fcnvfxt( 111 sgl_floating_point *srcptr, 112 unsigned int *nullptr, 113 dbl_integer *dstptr, 114 unsigned int *status) 115{ 116 register int src_exponent, resultp1; 117 register unsigned int src, temp, resultp2; 118 119 src = *srcptr; 120 src_exponent = Sgl_exponent(src) - SGL_BIAS; 121 122 /* 123 * Test for overflow 124 */ 125 if (src_exponent > DBL_FX_MAX_EXP) { 126 /* check for MININT */ 127 if ((src_exponent > DBL_FX_MAX_EXP + 1) || 128 Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) { 129 if (Sgl_iszero_sign(src)) { 130 resultp1 = 0x7fffffff; 131 resultp2 = 0xffffffff; 132 } 133 else { 134 resultp1 = 0x80000000; 135 resultp2 = 0; 136 } 137 if (Is_invalidtrap_enabled()) { 138 return(INVALIDEXCEPTION); 139 } 140 Set_invalidflag(); 141 Dint_copytoptr(resultp1,resultp2,dstptr); 142 return(NOEXCEPTION); 143 } 144 Dint_set_minint(resultp1,resultp2); 145 Dint_copytoptr(resultp1,resultp2,dstptr); 146 return(NOEXCEPTION); 147 } 148 /* 149 * Generate result 150 */ 151 if (src_exponent >= 0) { 152 temp = src; 153 Sgl_clear_signexponent_set_hidden(temp); 154 Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2); 155 if (Sgl_isone_sign(src)) { 156 Dint_setone_sign(resultp1,resultp2); 157 } 158 Dint_copytoptr(resultp1,resultp2,dstptr); 159 160 /* check for inexact */ 161 if (Sgl_isinexact_to_fix(src,src_exponent)) { 162 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 163 else Set_inexactflag(); 164 } 165 } 166 else { 167 Dint_setzero(resultp1,resultp2); 168 Dint_copytoptr(resultp1,resultp2,dstptr); 169 170 /* check for inexact */ 171 if (Sgl_isnotzero_exponentmantissa(src)) { 172 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 173 else Set_inexactflag(); 174 } 175 } 176 return(NOEXCEPTION); 177} 178 179/* 180 * Double Floating-point to Single Fixed-point 181 */ 182/*ARGSUSED*/ 183int 184dbl_to_sgl_fcnvfxt( 185 dbl_floating_point *srcptr, 186 unsigned int *nullptr, 187 int *dstptr, 188 unsigned int *status) 189{ 190 register unsigned int srcp1, srcp2, tempp1, tempp2; 191 register int src_exponent, result; 192 193 Dbl_copyfromptr(srcptr,srcp1,srcp2); 194 src_exponent = Dbl_exponent(srcp1) - DBL_BIAS; 195 196 /* 197 * Test for overflow 198 */ 199 if (src_exponent > SGL_FX_MAX_EXP) { 200 /* check for MININT */ 201 if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) { 202 if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff; 203 else result = 0x80000000; 204 205 if (Is_invalidtrap_enabled()) { 206 return(INVALIDEXCEPTION); 207 } 208 Set_invalidflag(); 209 *dstptr = result; 210 return(NOEXCEPTION); 211 } 212 } 213 /* 214 * Generate result 215 */ 216 if (src_exponent >= 0) { 217 tempp1 = srcp1; 218 tempp2 = srcp2; 219 Dbl_clear_signexponent_set_hidden(tempp1); 220 Int_from_dbl_mantissa(tempp1,tempp2,src_exponent); 221 if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP)) 222 result = -Dbl_allp1(tempp1); 223 else result = Dbl_allp1(tempp1); 224 *dstptr = result; 225 226 /* check for inexact */ 227 if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) { 228 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 229 else Set_inexactflag(); 230 } 231 } 232 else { 233 *dstptr = 0; 234 235 /* check for inexact */ 236 if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) { 237 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 238 else Set_inexactflag(); 239 } 240 } 241 return(NOEXCEPTION); 242} 243 244/* 245 * Double Floating-point to Double Fixed-point 246 */ 247/*ARGSUSED*/ 248int 249dbl_to_dbl_fcnvfxt( 250 dbl_floating_point *srcptr, 251 unsigned int *nullptr, 252 dbl_integer *dstptr, 253 unsigned int *status) 254{ 255 register int src_exponent, resultp1; 256 register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2; 257 258 Dbl_copyfromptr(srcptr,srcp1,srcp2); 259 src_exponent = Dbl_exponent(srcp1) - DBL_BIAS; 260 261 /* 262 * Test for overflow 263 */ 264 if (src_exponent > DBL_FX_MAX_EXP) { 265 /* check for MININT */ 266 if ((src_exponent > DBL_FX_MAX_EXP + 1) || 267 Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) { 268 if (Dbl_iszero_sign(srcp1)) { 269 resultp1 = 0x7fffffff; 270 resultp2 = 0xffffffff; 271 } 272 else { 273 resultp1 = 0x80000000; 274 resultp2 = 0; 275 } 276 if (Is_invalidtrap_enabled()) { 277 return(INVALIDEXCEPTION); 278 } 279 Set_invalidflag(); 280 Dint_copytoptr(resultp1,resultp2,dstptr); 281 return(NOEXCEPTION); 282 } 283 } 284 /* 285 * Generate result 286 */ 287 if (src_exponent >= 0) { 288 tempp1 = srcp1; 289 tempp2 = srcp2; 290 Dbl_clear_signexponent_set_hidden(tempp1); 291 Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent, 292 resultp1,resultp2); 293 if (Dbl_isone_sign(srcp1)) { 294 Dint_setone_sign(resultp1,resultp2); 295 } 296 Dint_copytoptr(resultp1,resultp2,dstptr); 297 298 /* check for inexact */ 299 if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) { 300 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 301 else Set_inexactflag(); 302 } 303 } 304 else { 305 Dint_setzero(resultp1,resultp2); 306 Dint_copytoptr(resultp1,resultp2,dstptr); 307 308 /* check for inexact */ 309 if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) { 310 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION); 311 else Set_inexactflag(); 312 } 313 } 314 return(NOEXCEPTION); 315}