/* $NetBSD: n_floor.c,v 1.9 2024/05/08 02:08:11 riastradh Exp $ */ /* * Copyright (c) 1985, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #ifndef lint #if 0 static char sccsid[] = "@(#)floor.c 8.1 (Berkeley) 6/4/93"; #endif #endif /* not lint */ #define _LIBM_STATIC #include "mathimpl.h" vc(L, 4503599627370496.0E0 ,0000,5c00,0000,0000, 55, 1.0) /* 2**55 */ ic(L, 4503599627370496.0E0, 52, 1.0) /* 2**52 */ #ifdef vccast #define L vccast(L) #endif __weak_alias(ceill, ceil) __weak_alias(floorl, floor) __weak_alias(truncl, trunc) __weak_alias(rintl, rint) /* * floor(x) := the largest integer no larger than x; * ceil(x) := -floor(-x), for all real x. * * Note: Inexact will be signaled if x is not an integer, as is * customary for IEEE 754. No other signal can be emitted. */ double floor(double x) { volatile double y; if ( #if !defined(__vax__)&&!defined(tahoe) x != x || /* NaN */ #endif /* !defined(__vax__)&&!defined(tahoe) */ x >= L) /* already an even integer */ return x; else if (x < (double)0) return -ceil(-x); else { /* now 0 <= x < L */ y = L+x; /* destructive store must be forced */ y -= L; /* an integer, and |x-y| < 1 */ return x < y ? y-(double)1 : y; } } float floorf(float x) { return floor((double)x); } double ceil(double x) { volatile double y; if ( #if !defined(__vax__)&&!defined(tahoe) x != x || /* NaN */ #endif /* !defined(__vax__)&&!defined(tahoe) */ x >= L) /* already an even integer */ return x; else if (x < (double)0) return -floor(-x); else { /* now 0 <= x < L */ y = L+x; /* destructive store must be forced */ y -= L; /* an integer, and |x-y| < 1 */ return x > y ? y+(double)1 : y; } } float ceilf(float x) { return ceil((double)x); } /* * algorithm for rint(x) in pseudo-pascal form ... * * real rint(x): real x; * ... delivers integer nearest x in direction of prevailing rounding * ... mode * const L = (last consecutive integer)/2 * = 2**55; for VAX D * = 2**52; for IEEE 754 Double * real s,t; * begin * if x != x then return x; ... NaN * if |x| >= L then return x; ... already an integer * s := copysign(L,x); * t := x + s; ... = (x+s) rounded to integer * return t - s * end; * * Note: Inexact will be signaled if x is not an integer, as is * customary for IEEE 754. No other signal can be emitted. */ double rint(double x) { double s; volatile double t; const double one = 1.0; #if !defined(__vax__)&&!defined(tahoe) if (x != x) /* NaN */ return (x); #endif /* !defined(__vax__)&&!defined(tahoe) */ if (copysign(x,one) >= L) /* already an integer */ return (x); s = copysign(L,x); t = x + s; /* x+s rounded to integer */ return (t - s); } float rintf(float x) { return rint((double)x); } long lrint(double x) { double s; volatile double t; const double one = 1.0; #if !defined(__vax__)&&!defined(tahoe) if (x != x) /* NaN */ return (x); #endif /* !defined(__vax__)&&!defined(tahoe) */ if (copysign(x,one) >= L) /* already an integer */ return (x); s = copysign(L,x); t = x + s; /* x+s rounded to integer */ return (t - s); } long long llrint(double x) { double s; volatile double t; const double one = 1.0; #if !defined(__vax__)&&!defined(tahoe) if (x != x) /* NaN */ return (x); #endif /* !defined(__vax__)&&!defined(tahoe) */ if (copysign(x,one) >= L) /* already an integer */ return (x); s = copysign(L,x); t = x + s; /* x+s rounded to integer */ return (t - s); } long lrintf(float x) { float s; volatile float t; const float one = 1.0; #if !defined(__vax__)&&!defined(tahoe) if (x != x) /* NaN */ return (x); #endif /* !defined(__vax__)&&!defined(tahoe) */ if (copysign(x,one) >= L) /* already an integer */ return (x); s = copysign(L,x); t = x + s; /* x+s rounded to integer */ return (t - s); } long long llrintf(float x) { float s; volatile float t; const float one = 1.0; #if !defined(__vax__)&&!defined(tahoe) if (x != x) /* NaN */ return (x); #endif /* !defined(__vax__)&&!defined(tahoe) */ if (copysign(x,one) >= L) /* already an integer */ return (x); s = copysign(L,x); t = x + s; /* x+s rounded to integer */ return (t - s); } double trunc(double x) { return x < 0 ? ceil(x) : floor(x); } float truncf(float x) { return x < 0 ? ceilf(x) : floorf(x); }
