12116Sjkh/* s_floorf.c -- float version of s_floor.c. 22116Sjkh * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 32116Sjkh */ 42116Sjkh 52116Sjkh/* 62116Sjkh * ==================================================== 72116Sjkh * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 82116Sjkh * 92116Sjkh * Developed at SunPro, a Sun Microsystems, Inc. business. 102116Sjkh * Permission to use, copy, modify, and distribute this 118870Srgrimes * software is freely granted, provided that this notice 122116Sjkh * is preserved. 132116Sjkh * ==================================================== 142116Sjkh */ 152116Sjkh 16176451Sdas#include <sys/cdefs.h> 17176451Sdas__FBSDID("$FreeBSD$"); 182116Sjkh 192116Sjkh/* 202116Sjkh * floorf(x) 212116Sjkh * Return x rounded toward -inf to integral value 222116Sjkh * Method: 232116Sjkh * Bit twiddling. 242116Sjkh * Exception: 252116Sjkh * Inexact flag raised if x not equal to floorf(x). 262116Sjkh */ 272116Sjkh 282116Sjkh#include "math.h" 292116Sjkh#include "math_private.h" 302116Sjkh 312116Sjkhstatic const float huge = 1.0e30; 322116Sjkh 3397413Salfredfloat 3497413Salfredfloorf(float x) 352116Sjkh{ 362116Sjkh int32_t i0,j0; 372116Sjkh u_int32_t i; 382116Sjkh GET_FLOAT_WORD(i0,x); 392116Sjkh j0 = ((i0>>23)&0xff)-0x7f; 402116Sjkh if(j0<23) { 412116Sjkh if(j0<0) { /* raise inexact if x != 0 */ 422116Sjkh if(huge+x>(float)0.0) {/* return 0*sign(x) if |x|<1 */ 438870Srgrimes if(i0>=0) {i0=0;} 442116Sjkh else if((i0&0x7fffffff)!=0) 452116Sjkh { i0=0xbf800000;} 462116Sjkh } 472116Sjkh } else { 482116Sjkh i = (0x007fffff)>>j0; 492116Sjkh if((i0&i)==0) return x; /* x is integral */ 502116Sjkh if(huge+x>(float)0.0) { /* raise inexact flag */ 512116Sjkh if(i0<0) i0 += (0x00800000)>>j0; 522116Sjkh i0 &= (~i); 532116Sjkh } 542116Sjkh } 552116Sjkh } else { 562116Sjkh if(j0==0x80) return x+x; /* inf or NaN */ 572116Sjkh else return x; /* x is integral */ 582116Sjkh } 592116Sjkh SET_FLOAT_WORD(x,i0); 602116Sjkh return x; 612116Sjkh} 62