1 /* Macros for the implementation of *cvt functions, long double version. 2 Copyright (C) 1996-2022 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 5 The GNU C Library is free software; you can redistribute it and/or 6 modify it under the terms of the GNU Lesser General Public 7 License as published by the Free Software Foundation; either 8 version 2.1 of the License, or (at your option) any later version. 9 10 The GNU C Library is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 13 Lesser General Public License for more details. 14 15 You should have received a copy of the GNU Lesser General Public 16 License along with the GNU C Library; if not, see 17 <https://www.gnu.org/licenses/>. */ 18 19 #include <float.h> 20 21 #define FLOAT_TYPE long double 22 #define FUNC_PREFIX q 23 #define FLOAT_FMT_FLAG "L" 24 #define FLOAT_NAME_EXT l 25 #define FLOAT_MIN_10_EXP LDBL_MIN_10_EXP 26 /* Actually we have to write (LDBL_DIG + log10 (LDBL_MAX_10_EXP)) but 27 we don't have log10 available in the preprocessor. Since we cannot 28 assume anything on the used `long double' format be generous. */ 29 #define MAXDIG (NDIGIT_MAX + 12) 30 #define FCVT_MAXDIG (LDBL_MAX_10_EXP + MAXDIG) 31 #if LDBL_MANT_DIG == 64 32 # define NDIGIT_MAX 21 33 #elif LDBL_MANT_DIG == 53 34 # define NDIGIT_MAX 17 35 #elif LDBL_MANT_DIG == 113 36 # define NDIGIT_MAX 36 37 #elif LDBL_MANT_DIG == 106 38 # define NDIGIT_MAX 34 39 #elif LDBL_MANT_DIG == 56 40 # define NDIGIT_MAX 18 41 #else 42 /* See IEEE 854 5.6, table 2 for this formula. Unfortunately we need a 43 compile time constant here, so we cannot use it. */ 44 # error "NDIGIT_MAX must be precomputed" 45 # define NDIGIT_MAX (lrint (ceil (M_LN2 / M_LN10 * LDBL_MANT_DIG + 1.0))) 46 #endif 47 #if LDBL_MIN_10_EXP == -37 48 # define FLOAT_MIN_10_NORM 1.0e-37L 49 #elif LDBL_MIN_10_EXP == -291 50 # define FLOAT_MIN_10_NORM 1.0e-291L 51 #elif LDBL_MIN_10_EXP == -307 52 # define FLOAT_MIN_10_NORM 1.0e-307L 53 #elif LDBL_MIN_10_EXP == -4931 54 # define FLOAT_MIN_10_NORM 1.0e-4931L 55 #else 56 /* libc can't depend on libm. */ 57 # error "FLOAT_MIN_10_NORM must be precomputed" 58 # define FLOAT_MIN_10_NORM exp10l (LDBL_MIN_10_EXP) 59 #endif 60