#include "tommath_private.h" #ifdef MP_SET_DOUBLE_C /* LibTomMath, multiple-precision integer library -- Tom St Denis */ /* SPDX-License-Identifier: Unlicense */ #if defined(__STDC_IEC_559__) || defined(__GCC_IEC_559) || defined(__x86_64__) || defined(_M_X64) || defined(_M_AMD64) || defined(__i386__) || defined(_M_X86) || defined(__aarch64__) || defined(__arm__) mp_err mp_set_double(mp_int *a, double b) { uint64_t frac; int exp; mp_err err; union { double dbl; uint64_t bits; } cast; cast.dbl = b; exp = (int)((unsigned)(cast.bits >> 52) & 0x7FFu); frac = (cast.bits & (((uint64_t)1 << 52) - (uint64_t)1)) | ((uint64_t)1 << 52); if (exp == 0x7FF) { /* +-inf, NaN */ return MP_VAL; } exp -= 1023 + 52; mp_set_u64(a, frac); err = (exp < 0) ? mp_div_2d(a, -exp, a, NULL) : mp_mul_2d(a, exp, a); if (err != MP_OKAY) { return err; } if (((cast.bits >> 63) != 0u) && !mp_iszero(a)) { a->sign = MP_NEG; } return MP_OKAY; } #else /* pragma message() not supported by several compilers (in mostly older but still used versions) */ # ifdef _MSC_VER # pragma message("mp_set_double implementation is only available on platforms with IEEE754 floating point format") # else # warning "mp_set_double implementation is only available on platforms with IEEE754 floating point format" # endif #endif #endif