/* * Copyright © 2005-2014 Rich Felker, et al. * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ #include "math_config.h" // This is only necessary because the implementation of isnan only works // properly when long double == double. // See: https://sourceware.org/ml/newlib/2014/msg00684.html #if !defined(_NEED_FLOAT_HUGE) float nexttowardf (float x, long double y) { uint32_t ux; uint32_t e; /* * We can't do this if y isn't nan as that might raise INEXACT doing * long double -> float conversion, and we don't want to do this * in long double for machines without long double HW as we won't * get any exceptions in that case. */ if (isnan(y)) return x + (issignaling(y) ? __builtin_nansf("") : (float) y); if (isnan(x)) return x + x; if ((long double) x == y) return (float) y; ux = asuint(x); if (x == 0) { ux = 1; if (signbit(y)) ux |= 0x80000000; x = asfloat(ux); force_eval_float(opt_barrier_float(x) * x); return x; } else if ((long double) x < y) { if (signbit(x)) ux--; else ux++; } else { if (signbit(x)) ux++; else ux--; } e = ux & 0x7f800000; /* raise overflow if ux.value is infinite and x is finite */ if (e == 0x7f800000) return check_oflowf(opt_barrier_float(x+x)); /* raise underflow if ux.value is subnormal or zero */ x = asfloat(ux); if (e == 0) return __math_denormf(x); return x; } _MATH_ALIAS_f_fl(nexttoward) #endif /* _NEED_FLOAT_HUGE */