s_rintf.c revision 175480
12116Sjkh/* s_rintf.c -- float version of s_rint.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 162116Sjkh#ifndef lint 1750476Speterstatic char rcsid[] = "$FreeBSD: head/lib/msun/src/s_rintf.c 175480 2008-01-19 16:37:57Z bde $"; 182116Sjkh#endif 192116Sjkh 20175480Sbde#include <float.h> 21175480Sbde#include <stdint.h> 22175480Sbde 232116Sjkh#include "math.h" 242116Sjkh#include "math_private.h" 252116Sjkh 26130285Sdasstatic const float 272116SjkhTWO23[2]={ 282116Sjkh 8.3886080000e+06, /* 0x4b000000 */ 292116Sjkh -8.3886080000e+06, /* 0xcb000000 */ 302116Sjkh}; 312116Sjkh 3297413Salfredfloat 3397413Salfredrintf(float x) 342116Sjkh{ 352116Sjkh int32_t i0,j0,sx; 36175480Sbde float w,t; 372116Sjkh GET_FLOAT_WORD(i0,x); 382116Sjkh sx = (i0>>31)&1; 392116Sjkh j0 = ((i0>>23)&0xff)-0x7f; 402116Sjkh if(j0<23) { 418870Srgrimes if(j0<0) { 422116Sjkh if((i0&0x7fffffff)==0) return x; 43175480Sbde STRICT_ASSIGN(float,w,TWO23[sx]+x); 442116Sjkh t = w-TWO23[sx]; 45153046Sbde GET_FLOAT_WORD(i0,t); 46153046Sbde SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31)); 472116Sjkh return t; 482116Sjkh } 49175480Sbde STRICT_ASSIGN(float,w,TWO23[sx]+x); 50130285Sdas return w-TWO23[sx]; 512116Sjkh } 52130285Sdas if(j0==0x80) return x+x; /* inf or NaN */ 53130285Sdas else return x; /* x is integral */ 542116Sjkh} 55