1 /* s_rintf.c -- float version of s_rint.c. 2 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com. 3 */ 4 5 /* 6 * ==================================================== 7 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 8 * 9 * Developed at SunPro, a Sun Microsystems, Inc. business. 10 * Permission to use, copy, modify, and distribute this 11 * software is freely granted, provided that this notice 12 * is preserved. 13 * ==================================================== 14 */ 15 16 #include <sys/cdefs.h> 17 #include <float.h> 18 #include <stdint.h> 19 20 #include "math.h" 21 #include "math_private.h" 22 23 static const float 24 TWO23[2]={ 25 8.3886080000e+06, /* 0x4b000000 */ 26 -8.3886080000e+06, /* 0xcb000000 */ 27 }; 28 29 float 30 rintf(float x) 31 { 32 int32_t i0,j0,sx; 33 float w,t; 34 GET_FLOAT_WORD(i0,x); 35 sx = (i0>>31)&1; 36 j0 = ((i0>>23)&0xff)-0x7f; 37 if(j0<23) { 38 if(j0<0) { 39 if((i0&0x7fffffff)==0) return x; 40 STRICT_ASSIGN(float,w,TWO23[sx]+x); 41 t = w-TWO23[sx]; 42 GET_FLOAT_WORD(i0,t); 43 SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31)); 44 return t; 45 } 46 STRICT_ASSIGN(float,w,TWO23[sx]+x); 47 return w-TWO23[sx]; 48 } 49 if(j0==0x80) return x+x; /* inf or NaN */ 50 else return x; /* x is integral */ 51 } 52