/* Copyright (C) 2007 Free Software Foundation, Inc. This file is part of GCC. GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. In addition to the permissions in the GNU General Public License, the Free Software Foundation gives you unlimited permission to link the compiled version of this file into combinations with other programs, and to distribute those combinations without any restriction coming from the use of this file. (The General Public License restrictions do apply in other respects; for example, they cover modification of the file, and distribution when not linked into a combine executable.) GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GCC; see the file COPYING. If not, write to the Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include "bid_internal.h" #include "bid128_2_str.h" #include "bid128_2_str_macros.h" #define MAX_FORMAT_DIGITS 16 #define DECIMAL_EXPONENT_BIAS 398 #define MAX_DECIMAL_EXPONENT 767 #if DECIMAL_CALL_BY_REFERENCE void __bid64_to_string (char *ps, UINT64 * px _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM _EXC_INFO_PARAM) { UINT64 x; #else void __bid64_to_string (char *ps, UINT64 x _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM _EXC_INFO_PARAM) { #endif // the destination string (pointed to by ps) must be pre-allocated UINT64 sign_x, coefficient_x, D, ER10; int istart, exponent_x, j, digits_x, bin_expon_cx; int_float tempx; UINT32 MiDi[12], *ptr; UINT64 HI_18Dig, LO_18Dig, Tmp; char *c_ptr_start, *c_ptr; int midi_ind, k_lcv, len; #if DECIMAL_CALL_BY_REFERENCE #if !DECIMAL_GLOBAL_ROUNDING _IDEC_round rnd_mode = *prnd_mode; #endif x = *px; #endif // unpack arguments, check for NaN or Infinity if (!unpack_BID64 (&sign_x, &exponent_x, &coefficient_x, x)) { // x is Inf. or NaN or 0 // Inf or NaN? if ((x & 0x7800000000000000ull) == 0x7800000000000000ull) { if ((x & 0x7c00000000000000ull) == 0x7c00000000000000ull) { ps[0] = 'N'; ps[1] = 'a'; ps[2] = 'N'; ps[3] = 0; return; } // x is Inf ps[0] = (sign_x) ? '-' : '+'; ps[1] = 'I'; ps[2] = 'n'; ps[3] = 'f'; ps[4] = 0; return; } // 0 istart = 0; if (sign_x) { ps[istart++] = '-'; } ps[istart++] = '0'; ps[istart++] = 'E'; exponent_x -= 398; if (exponent_x < 0) { ps[istart++] = '-'; exponent_x = -exponent_x; } else ps[istart++] = '+'; if (exponent_x) { // get decimal digits in coefficient_x tempx.d = (float) exponent_x; bin_expon_cx = ((tempx.i >> 23) & 0xff) - 0x7f; digits_x = __bid_estimate_decimal_digits[bin_expon_cx]; if ((UINT64)exponent_x >= __bid_power10_table_128[digits_x].w[0]) digits_x++; j = istart + digits_x - 1; istart = j + 1; // 2^32/10 ER10 = 0x1999999a; while (exponent_x > 9) { D = (UINT64) exponent_x *ER10; D >>= 32; exponent_x = exponent_x - (D << 1) - (D << 3); ps[j--] = '0' + (char) exponent_x; exponent_x = D; } ps[j] = '0' + (char) exponent_x; } else { ps[istart++] = '0'; } ps[istart] = 0; return; } // convert expon, coeff to ASCII exponent_x -= DECIMAL_EXPONENT_BIAS; ER10 = 0x1999999a; istart = 0; if (sign_x) { ps[0] = '-'; istart = 1; } // if zero or non-canonical, set coefficient to '0' if ((coefficient_x > 9999999999999999ull) || // non-canonical ((coefficient_x == 0)) // significand is zero ) { ps[istart++] = '0'; } else { /* **************************************************** This takes a bid coefficient in C1.w[1],C1.w[0] and put the converted character sequence at location starting at &(str[k]). The function returns the number of MiDi returned. Note that the character sequence does not have leading zeros EXCEPT when the input is of zero value. It will then output 1 character '0' The algorithm essentailly tries first to get a sequence of Millenial Digits "MiDi" and then uses table lookup to get the character strings of these MiDis. **************************************************** */ /* Algorithm first decompose possibly 34 digits in hi and lo 18 digits. (The high can have at most 16 digits). It then uses macro that handle 18 digit portions. The first step is to get hi and lo such that 2^(64) C1.w[1] + C1.w[0] = hi * 10^18 + lo, 0 <= lo < 10^18. We use a table lookup method to obtain the hi and lo 18 digits. [C1.w[1],C1.w[0]] = c_8 2^(107) + c_7 2^(101) + ... + c_0 2^(59) + d where 0 <= d < 2^59 and each c_j has 6 bits. Because d fits in 18 digits, we set hi = 0, and lo = d to begin with. We then retrieve from a table, for j = 0, 1, ..., 8 that gives us A and B where c_j 2^(59+6j) = A * 10^18 + B. hi += A ; lo += B; After each accumulation into lo, we normalize immediately. So at the end, we have the decomposition as we need. */ Tmp = coefficient_x >> 59; LO_18Dig = (coefficient_x << 5) >> 5; HI_18Dig = 0; k_lcv = 0; while (Tmp) { midi_ind = (int) (Tmp & 0x000000000000003FLL); midi_ind <<= 1; Tmp >>= 6; HI_18Dig += __bid_mod10_18_tbl[k_lcv][midi_ind++]; LO_18Dig += __bid_mod10_18_tbl[k_lcv++][midi_ind]; __L0_Normalize_10to18 (HI_18Dig, LO_18Dig); } ptr = MiDi; __L1_Split_MiDi_6_Lead (LO_18Dig, ptr); len = ptr - MiDi; c_ptr_start = &(ps[istart]); c_ptr = c_ptr_start; /* now convert the MiDi into character strings */ __L0_MiDi2Str_Lead (MiDi[0], c_ptr); for (k_lcv = 1; k_lcv < len; k_lcv++) { __L0_MiDi2Str (MiDi[k_lcv], c_ptr); } istart = istart + (c_ptr - c_ptr_start); } ps[istart++] = 'E'; if (exponent_x < 0) { ps[istart++] = '-'; exponent_x = -exponent_x; } else ps[istart++] = '+'; if (exponent_x) { // get decimal digits in coefficient_x tempx.d = (float) exponent_x; bin_expon_cx = ((tempx.i >> 23) & 0xff) - 0x7f; digits_x = __bid_estimate_decimal_digits[bin_expon_cx]; if ((UINT64)exponent_x >= __bid_power10_table_128[digits_x].w[0]) digits_x++; j = istart + digits_x - 1; istart = j + 1; // 2^32/10 ER10 = 0x1999999a; while (exponent_x > 9) { D = (UINT64) exponent_x *ER10; D >>= 32; exponent_x = exponent_x - (D << 1) - (D << 3); ps[j--] = '0' + (char) exponent_x; exponent_x = D; } ps[j] = '0' + (char) exponent_x; } else { ps[istart++] = '0'; } ps[istart] = 0; return; } #if DECIMAL_CALL_BY_REFERENCE void __bid64_from_string (UINT64 * pres, char *ps _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM _EXC_INFO_PARAM) { #else UINT64 __bid64_from_string (char *ps _RND_MODE_PARAM _EXC_FLAGS_PARAM _EXC_MASKS_PARAM _EXC_INFO_PARAM) { #endif UINT64 sign_x, coefficient_x = 0, rounded = 0, res; int expon_x = 0, sgn_expon, ndigits, add_expon = 0, midpoint = 0, rounded_up = 0; int dec_expon_scale = 0, right_radix_leading_zeros = 0, rdx_pt_enc = 0; unsigned fpsc; char c; #if DECIMAL_CALL_BY_REFERENCE #if !DECIMAL_GLOBAL_ROUNDING _IDEC_round rnd_mode = *prnd_mode; #endif #endif // eliminate leading whitespace while (((*ps == ' ') || (*ps == '\t')) && (*ps)) ps++; // get first non-whitespace character c = *ps; // detect special cases (INF or NaN) if (!c || (c != '.' && c != '-' && c != '+' && (c < '0' || c > '9'))) { // Infinity? if ((tolower_macro (ps[0]) == 'i' && tolower_macro (ps[1]) == 'n' && tolower_macro (ps[2]) == 'f') && (!ps[3] || (tolower_macro (ps[3]) == 'i' && tolower_macro (ps[4]) == 'n' && tolower_macro (ps[5]) == 'i' && tolower_macro (ps[6]) == 't' && tolower_macro (ps[7]) == 'y' && !ps[8]))) { res = 0x7800000000000000ull; BID_RETURN (res); } // return sNaN if (tolower_macro (ps[0]) == 's' && tolower_macro (ps[1]) == 'n' && tolower_macro (ps[2]) == 'a' && tolower_macro (ps[3]) == 'n') { // case insensitive check for snan res = 0x7e00000000000000ull; BID_RETURN (res); } else { // return qNaN res = 0x7c00000000000000ull; BID_RETURN (res); } } // detect +INF or -INF if ((tolower_macro (ps[1]) == 'i' && tolower_macro (ps[2]) == 'n' && tolower_macro (ps[3]) == 'f') && (!ps[4] || (tolower_macro (ps[4]) == 'i' && tolower_macro (ps[5]) == 'n' && tolower_macro (ps[6]) == 'i' && tolower_macro (ps[7]) == 't' && tolower_macro (ps[8]) == 'y' && !ps[9]))) { if (c == '+') res = 0x7800000000000000ull; else if (c == '-') res = 0xf800000000000000ull; else res = 0x7c00000000000000ull; BID_RETURN (res); } // if +sNaN, +SNaN, -sNaN, or -SNaN if (tolower_macro (ps[1]) == 's' && tolower_macro (ps[2]) == 'n' && tolower_macro (ps[3]) == 'a' && tolower_macro (ps[4]) == 'n') { if (c == '-') res = 0xfe00000000000000ull; else res = 0x7e00000000000000ull; BID_RETURN (res); } // determine sign if (c == '-') sign_x = 0x8000000000000000ull; else sign_x = 0; // get next character if leading +/- sign if (c == '-' || c == '+') { ps++; c = *ps; } // if c isn't a decimal point or a decimal digit, return NaN if (c != '.' && (c < '0' || c > '9')) { // return NaN res = 0x7c00000000000000ull | sign_x; BID_RETURN (res); } rdx_pt_enc = 0; // detect zero (and eliminate/ignore leading zeros) if (*(ps) == '0' || *(ps) == '.') { if (*(ps) == '.') { rdx_pt_enc = 1; ps++; } // if all numbers are zeros (with possibly 1 radix point, the number is zero // should catch cases such as: 000.0 while (*ps == '0') { ps++; // for numbers such as 0.0000000000000000000000000000000000001001, // we want to count the leading zeros if (rdx_pt_enc) { right_radix_leading_zeros++; } // if this character is a radix point, make sure we haven't already // encountered one if (*(ps) == '.') { if (rdx_pt_enc == 0) { rdx_pt_enc = 1; // if this is the first radix point, and the next character is NULL, // we have a zero if (!*(ps + 1)) { res = ((UINT64) (398 - right_radix_leading_zeros) << 53) | sign_x; BID_RETURN (res); } ps = ps + 1; } else { // if 2 radix points, return NaN res = 0x7c00000000000000ull | sign_x; BID_RETURN (res); } } else if (!*(ps)) { //pres->w[1] = 0x3040000000000000ull | sign_x; res = ((UINT64) (398 - right_radix_leading_zeros) << 53) | sign_x; BID_RETURN (res); } } } c = *ps; ndigits = 0; while ((c >= '0' && c <= '9') || c == '.') { if (c == '.') { if (rdx_pt_enc) { // return NaN res = 0x7c00000000000000ull | sign_x; BID_RETURN (res); } rdx_pt_enc = 1; ps++; c = *ps; continue; } dec_expon_scale += rdx_pt_enc; ndigits++; if (ndigits <= 16) { coefficient_x = (coefficient_x << 1) + (coefficient_x << 3); coefficient_x += (UINT64) (c - '0'); } else if (ndigits == 17) { // coefficient rounding midpoint = (c == '5' && !(coefficient_x & 1)) ? 1 : 0; // if coefficient is even and c is 5, prepare to round up if // subsequent digit is nonzero // if str[MAXDIG+1] > 5, we MUST round up // if str[MAXDIG+1] == 5 and coefficient is ODD, ROUND UP! if (c > '5' || (c == '5' && (coefficient_x & 1))) { coefficient_x++; rounded_up = 1; if (coefficient_x == 10000000000000000ull) { coefficient_x = 1000000000000000ull; add_expon = 1; } } if (c > '0') rounded = 1; add_expon += 1; } else { // ndigits > 17 add_expon++; if (midpoint && c > '0') { coefficient_x++; midpoint = 0; rounded_up = 1; } if (c > '0') rounded = 1; } ps++; c = *ps; } add_expon -= (dec_expon_scale + right_radix_leading_zeros); if (!c) { res = fast_get_BID64_check_OF (sign_x, add_expon + DECIMAL_EXPONENT_BIAS, coefficient_x, 0, &fpsc); BID_RETURN (res); } if (c != 'E' && c != 'e') { // return NaN res = 0x7c00000000000000ull | sign_x; BID_RETURN (res); } ps++; c = *ps; sgn_expon = (c == '-') ? 1 : 0; if (c == '-' || c == '+') { ps++; c = *ps; } if (!c || c < '0' || c > '9') { // return NaN res = 0x7c00000000000000ull | sign_x; BID_RETURN (res); } while (c >= '0' && c <= '9') { expon_x = (expon_x << 1) + (expon_x << 3); expon_x += (int) (c - '0'); ps++; c = *ps; } if (c) { // return NaN res = 0x7c00000000000000ull | sign_x; BID_RETURN (res); } if (sgn_expon) expon_x = -expon_x; expon_x += add_expon + DECIMAL_EXPONENT_BIAS; if (expon_x < 0) { if (rounded_up) coefficient_x--; rnd_mode = 0; res = get_BID64_UF (sign_x, expon_x, coefficient_x, rounded, rnd_mode, &fpsc); BID_RETURN (res); } res = get_BID64 (sign_x, expon_x, coefficient_x, rnd_mode, &fpsc); BID_RETURN (res); }