1/* Copyright (C) 2007, 2009 Free Software Foundation, Inc. 2 3This file is part of GCC. 4 5GCC is free software; you can redistribute it and/or modify it under 6the terms of the GNU General Public License as published by the Free 7Software Foundation; either version 3, or (at your option) any later 8version. 9 10GCC is distributed in the hope that it will be useful, but WITHOUT ANY 11WARRANTY; without even the implied warranty of MERCHANTABILITY or 12FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13for more details. 14 15Under Section 7 of GPL version 3, you are granted additional 16permissions described in the GCC Runtime Library Exception, version 173.1, as published by the Free Software Foundation. 18 19You should have received a copy of the GNU General Public License and 20a copy of the GCC Runtime Library Exception along with this program; 21see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 22<http://www.gnu.org/licenses/>. */ 23 24#define BID_128RES 25#include "bid_internal.h" 26 27/* 28 * Takes a BID32 as input and converts it to a BID128 and returns it. 29 */ 30TYPE0_FUNCTION_ARGTYPE1_NORND (UINT128, bid32_to_bid128, UINT32, x) 31 32 UINT128 new_coeff, res; 33 UINT32 sign_x; 34 int exponent_x; 35 UINT32 coefficient_x; 36 37if (!unpack_BID32 (&sign_x, &exponent_x, &coefficient_x, x)) { 38if (((x) & 0x78000000) == 0x78000000) { 39#ifdef SET_STATUS_FLAGS 40 if (((x) & 0x7e000000) == 0x7e000000) // sNaN 41 __set_status_flags (pfpsf, INVALID_EXCEPTION); 42#endif 43 res.w[0] = (coefficient_x & 0x000fffff); 44 __mul_64x128_low (res, res.w[0], power10_table_128[27]); 45 res.w[1] |= 46 ((((UINT64) coefficient_x) << 32) & 0xfc00000000000000ull); 47 48 BID_RETURN (res); 49} 50} 51 52new_coeff.w[0] = coefficient_x; 53new_coeff.w[1] = 0; 54get_BID128_very_fast (&res, ((UINT64) sign_x) << 32, 55 exponent_x + DECIMAL_EXPONENT_BIAS_128 - 56 DECIMAL_EXPONENT_BIAS_32, new_coeff); 57BID_RETURN (res); 58} // convert_bid32_to_bid128 59 60 61/* 62 * Takes a BID128 as input and converts it to a BID32 and returns it. 63 */ 64#if DECIMAL_CALL_BY_REFERENCE 65 66void 67bid128_to_bid32 (UINT32 * pres, 68 UINT128 * 69 px _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM 70 _EXC_INFO_PARAM) { 71 UINT128 x = *px; 72#else 73 74UINT32 75bid128_to_bid32 (UINT128 x _RND_MODE_PARAM _EXC_FLAGS_PARAM 76 _EXC_MASKS_PARAM _EXC_INFO_PARAM) { 77#endif 78 UINT128 CX, T128, TP128, Qh, Ql, Qh1, Stemp, Tmp, Tmp1, CX1; 79 UINT64 sign_x, carry, cy; 80 SINT64 D; 81 UINT32 res; 82 int_float f64, fx; 83 int exponent_x, extra_digits, amount, bin_expon_cx, uf_check = 0; 84 unsigned rmode, status; 85 86#if DECIMAL_CALL_BY_REFERENCE 87#if !DECIMAL_GLOBAL_ROUNDING 88 _IDEC_round rnd_mode = *prnd_mode; 89#endif 90#endif 91 92 BID_SWAP128 (x); 93 // unpack arguments, check for NaN or Infinity or 0 94 if (!unpack_BID128_value (&sign_x, &exponent_x, &CX, x)) { 95 if (((x.w[1]) & 0x7800000000000000ull) == 0x7800000000000000ull) { 96 Tmp.w[1] = (CX.w[1] & 0x00003fffffffffffull); 97 Tmp.w[0] = CX.w[0]; 98 TP128 = reciprocals10_128[27]; 99 __mul_128x128_full (Qh, Ql, Tmp, TP128); 100 amount = recip_scale[27] - 64; 101 res = ((CX.w[1] >> 32) & 0xfc000000) | (Qh.w[1] >> amount); 102#ifdef SET_STATUS_FLAGS 103 if ((x.w[1] & SNAN_MASK64) == SNAN_MASK64) // sNaN 104 __set_status_flags (pfpsf, INVALID_EXCEPTION); 105#endif 106 BID_RETURN_VAL (res); 107 } 108 // x is 0 109 exponent_x = 110 exponent_x - DECIMAL_EXPONENT_BIAS_128 + DECIMAL_EXPONENT_BIAS_32; 111 if (exponent_x < 0) 112 exponent_x = 0; 113 if (exponent_x > DECIMAL_MAX_EXPON_32) 114 exponent_x = DECIMAL_MAX_EXPON_32; 115 res = (sign_x >> 32) | (exponent_x << 23); 116 BID_RETURN_VAL (res); 117 118 } 119 120 if (CX.w[1] || (CX.w[0] >= 10000000)) { 121 // find number of digits in coefficient 122 // 2^64 123 f64.i = 0x5f800000; 124 // fx ~ CX 125 fx.d = (float) CX.w[1] * f64.d + (float) CX.w[0]; 126 bin_expon_cx = ((fx.i >> 23) & 0xff) - 0x7f; 127 extra_digits = estimate_decimal_digits[bin_expon_cx] - 7; 128 // scale = 38-estimate_decimal_digits[bin_expon_cx]; 129 D = CX.w[1] - power10_index_binexp_128[bin_expon_cx].w[1]; 130 if (D > 0 131 || (!D 132 && CX.w[0] >= power10_index_binexp_128[bin_expon_cx].w[0])) 133 extra_digits++; 134 135 exponent_x += extra_digits; 136 137#ifndef IEEE_ROUND_NEAREST_TIES_AWAY 138#ifndef IEEE_ROUND_NEAREST 139 rmode = rnd_mode; 140 if (sign_x && (unsigned) (rmode - 1) < 2) 141 rmode = 3 - rmode; 142#else 143 rmode = 0; 144#endif 145#else 146 rmode = 0; 147#endif 148 if (exponent_x < 149 DECIMAL_EXPONENT_BIAS_128 - DECIMAL_EXPONENT_BIAS_32) { 150 uf_check = 1; 151 if (-extra_digits + exponent_x - DECIMAL_EXPONENT_BIAS_128 + 152 DECIMAL_EXPONENT_BIAS_32 + 35 >= 0) { 153 if (exponent_x == 154 DECIMAL_EXPONENT_BIAS_128 - DECIMAL_EXPONENT_BIAS_32 - 1) { 155 T128 = round_const_table_128[rmode][extra_digits]; 156 __add_carry_out (CX1.w[0], carry, T128.w[0], CX.w[0]); 157 CX1.w[1] = CX.w[1] + T128.w[1] + carry; 158 if (__unsigned_compare_ge_128 159 (CX1, power10_table_128[extra_digits + 7])) 160 uf_check = 0; 161 } 162 extra_digits = 163 extra_digits + DECIMAL_EXPONENT_BIAS_128 - 164 DECIMAL_EXPONENT_BIAS_32 - exponent_x; 165 exponent_x = 166 DECIMAL_EXPONENT_BIAS_128 - DECIMAL_EXPONENT_BIAS_32; 167 } else 168 rmode = ROUNDING_TO_ZERO; 169 } 170 171 T128 = round_const_table_128[rmode][extra_digits]; 172 __add_carry_out (CX.w[0], carry, T128.w[0], CX.w[0]); 173 CX.w[1] = CX.w[1] + T128.w[1] + carry; 174 175 TP128 = reciprocals10_128[extra_digits]; 176 __mul_128x128_full (Qh, Ql, CX, TP128); 177 amount = recip_scale[extra_digits]; 178 179 if (amount >= 64) { 180 CX.w[0] = Qh.w[1] >> (amount - 64); 181 CX.w[1] = 0; 182 } else { 183 __shr_128 (CX, Qh, amount); 184 } 185 186#ifndef IEEE_ROUND_NEAREST_TIES_AWAY 187#ifndef IEEE_ROUND_NEAREST 188 if (!(rnd_mode)) 189#endif 190 if (CX.w[0] & 1) { 191 // check whether fractional part of initial_P/10^ed1 is exactly .5 192 193 // get remainder 194 __shl_128_long (Qh1, Qh, (128 - amount)); 195 196 if (!Qh1.w[1] && !Qh1.w[0] 197 && (Ql.w[1] < reciprocals10_128[extra_digits].w[1] 198 || (Ql.w[1] == reciprocals10_128[extra_digits].w[1] 199 && Ql.w[0] < reciprocals10_128[extra_digits].w[0]))) { 200 CX.w[0]--; 201 } 202 } 203#endif 204 205 206 { 207 status = INEXACT_EXCEPTION; 208 // get remainder 209 __shl_128_long (Qh1, Qh, (128 - amount)); 210 211 switch (rmode) { 212 case ROUNDING_TO_NEAREST: 213 case ROUNDING_TIES_AWAY: 214 // test whether fractional part is 0 215 if (Qh1.w[1] == 0x8000000000000000ull && (!Qh1.w[0]) 216 && (Ql.w[1] < reciprocals10_128[extra_digits].w[1] 217 || (Ql.w[1] == reciprocals10_128[extra_digits].w[1] 218 && Ql.w[0] < reciprocals10_128[extra_digits].w[0]))) 219 status = EXACT_STATUS; 220 break; 221 case ROUNDING_DOWN: 222 case ROUNDING_TO_ZERO: 223 if ((!Qh1.w[1]) && (!Qh1.w[0]) 224 && (Ql.w[1] < reciprocals10_128[extra_digits].w[1] 225 || (Ql.w[1] == reciprocals10_128[extra_digits].w[1] 226 && Ql.w[0] < reciprocals10_128[extra_digits].w[0]))) 227 status = EXACT_STATUS; 228 break; 229 default: 230 // round up 231 __add_carry_out (Stemp.w[0], cy, Ql.w[0], 232 reciprocals10_128[extra_digits].w[0]); 233 __add_carry_in_out (Stemp.w[1], carry, Ql.w[1], 234 reciprocals10_128[extra_digits].w[1], cy); 235 __shr_128_long (Qh, Qh1, (128 - amount)); 236 Tmp.w[0] = 1; 237 Tmp.w[1] = 0; 238 __shl_128_long (Tmp1, Tmp, amount); 239 Qh.w[0] += carry; 240 if (Qh.w[0] < carry) 241 Qh.w[1]++; 242 if (__unsigned_compare_ge_128 (Qh, Tmp1)) 243 status = EXACT_STATUS; 244 } 245 246 if (status != EXACT_STATUS) { 247 if (uf_check) { 248 status |= UNDERFLOW_EXCEPTION; 249 } 250#ifdef SET_STATUS_FLAGS 251 __set_status_flags (pfpsf, status); 252#endif 253 } 254 } 255 256 } 257 258 res = 259 get_BID32 ((UINT32) (sign_x >> 32), 260 exponent_x - DECIMAL_EXPONENT_BIAS_128 + 261 DECIMAL_EXPONENT_BIAS_32, CX.w[0], rnd_mode, pfpsf); 262 BID_RETURN_VAL (res); 263 264} 265