forked from KolibriOS/kolibrios
85 lines
1.7 KiB
C
85 lines
1.7 KiB
C
|
/* sf_rint.c -- float version of s_rint.c.
|
||
|
|
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
|
||
|
|
*/
|
||
|
|
|
||
|
|
/*
|
||
|
|
* ====================================================
|
||
|
|
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
|
||
|
|
*
|
||
|
|
* Developed at SunPro, a Sun Microsystems, Inc. business.
|
||
|
|
* Permission to use, copy, modify, and distribute this
|
||
|
|
* software is freely granted, provided that this notice
|
||
|
|
* is preserved.
|
||
|
|
* ====================================================
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include "fdlibm.h"
|
||
|
|
|
||
|
|
#ifdef __STDC__
|
||
|
|
static const float
|
||
|
|
#else
|
||
|
|
static float
|
||
|
|
#endif
|
||
|
|
TWO23[2]={
|
||
|
|
8.3886080000e+06, /* 0x4b000000 */
|
||
|
|
-8.3886080000e+06, /* 0xcb000000 */
|
||
|
|
};
|
||
|
|
|
||
|
|
#ifdef __STDC__
|
||
|
|
float rintf(float x)
|
||
|
|
#else
|
||
|
|
float rintf(x)
|
||
|
|
float x;
|
||
|
|
#endif
|
||
|
|
{
|
||
|
|
__int32_t i0,j0,sx;
|
||
|
|
__uint32_t i,i1,ix;
|
||
|
|
float t;
|
||
|
|
volatile float w;
|
||
|
|
GET_FLOAT_WORD(i0,x);
|
||
|
|
sx = (i0>>31)&1;
|
||
|
|
ix = (i0&0x7fffffff);
|
||
|
|
j0 = (ix>>23)-0x7f;
|
||
|
|
if(j0<23) {
|
||
|
|
if(FLT_UWORD_IS_ZERO(ix))
|
||
|
|
return x;
|
||
|
|
if(j0<0) {
|
||
|
|
i1 = (i0&0x07fffff);
|
||
|
|
i0 &= 0xfff00000;
|
||
|
|
i0 |= ((i1|-i1)>>9)&0x400000;
|
||
|
|
SET_FLOAT_WORD(x,i0);
|
||
|
|
w = TWO23[sx]+x;
|
||
|
|
t = w-TWO23[sx];
|
||
|
|
GET_FLOAT_WORD(i0,t);
|
||
|
|
SET_FLOAT_WORD(t,(i0&0x7fffffff)|(sx<<31));
|
||
|
|
return t;
|
||
|
|
} else {
|
||
|
|
i = (0x007fffff)>>j0;
|
||
|
|
if((i0&i)==0) return x; /* x is integral */
|
||
|
|
i>>=1;
|
||
|
|
if((i0&i)!=0) i0 = (i0&(~i))|((0x200000)>>j0);
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
if(!FLT_UWORD_IS_FINITE(ix)) return x+x; /* inf or NaN */
|
||
|
|
else
|
||
|
|
return x; /* x is integral */
|
||
|
|
}
|
||
|
|
SET_FLOAT_WORD(x,i0);
|
||
|
|
w = TWO23[sx]+x;
|
||
|
|
return w-TWO23[sx];
|
||
|
|
}
|
||
|
|
|
||
|
|
#ifdef _DOUBLE_IS_32BITS
|
||
|
|
|
||
|
|
#ifdef __STDC__
|
||
|
|
double rint(double x)
|
||
|
|
#else
|
||
|
|
double rint(x)
|
||
|
|
double x;
|
||
|
|
#endif
|
||
|
|
{
|
||
|
|
return (double) rintf((float) x);
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* defined(_DOUBLE_IS_32BITS) */
|