mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-22 19:00:07 +00:00
91 lines
2.1 KiB
C
91 lines
2.1 KiB
C
/* s_floorl.c -- long double version of s_floor.c.
|
|
* Conversion to long double by Ulrich Drepper,
|
|
* Cygnus Support, drepper@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.
|
|
* ====================================================
|
|
*/
|
|
|
|
#if defined(LIBM_SCCS) && !defined(lint)
|
|
static char rcsid[] = "$NetBSD: $";
|
|
#endif
|
|
|
|
/*
|
|
* floorl(x)
|
|
* Return x rounded toward -inf to integral value
|
|
* Method:
|
|
* Bit twiddling.
|
|
* Exception:
|
|
* Inexact flag raised if x not equal to floor(x).
|
|
*/
|
|
|
|
#include "math.h"
|
|
#include "math_private.h"
|
|
|
|
#ifdef __STDC__
|
|
static const long double huge = 1.0e4930;
|
|
#else
|
|
static long double huge = 1.0e4930;
|
|
#endif
|
|
|
|
#ifdef __STDC__
|
|
long double __floorl(long double x)
|
|
#else
|
|
long double __floorl(x)
|
|
long double x;
|
|
#endif
|
|
{
|
|
int32_t i1,j0;
|
|
u_int32_t i,j,se,i0,sx;
|
|
GET_LDOUBLE_WORDS(se,i0,i1,x);
|
|
sx = (se>>15)&1;
|
|
j0 = (se&0x7fff)-0x3fff;
|
|
if(j0<31) {
|
|
if(j0<0) { /* raise inexact if x != 0 */
|
|
if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
|
|
if(sx==0) {se=0;i0=i1=0;}
|
|
else if(((se&0x7fff)|i0|i1)!=0)
|
|
{ se=0xbfff;i0=i1=0;}
|
|
}
|
|
} else {
|
|
i = (0x7fffffff)>>j0;
|
|
if(((i0&i)|i1)==0) return x; /* x is integral */
|
|
if(huge+x>0.0) { /* raise inexact flag */
|
|
if(sx) {
|
|
if (j0>0) i0 += (0x80000000)>>j0;
|
|
else ++se;
|
|
}
|
|
i0 &= (~i); i1=0;
|
|
}
|
|
}
|
|
} else if (j0>62) {
|
|
if(j0==0x4000) return x+x; /* inf or NaN */
|
|
else return x; /* x is integral */
|
|
} else {
|
|
i = ((u_int32_t)(0xffffffff))>>(j0-31);
|
|
if((i1&i)==0) return x; /* x is integral */
|
|
if(huge+x>0.0) { /* raise inexact flag */
|
|
if(sx) {
|
|
if(j0==31) i0+=1;
|
|
else {
|
|
j = i1+(1<<(63-j0));
|
|
if(j<i1) i0 +=1 ; /* got a carry */
|
|
i1=j;
|
|
}
|
|
}
|
|
i1 &= (~i);
|
|
}
|
|
}
|
|
SET_LDOUBLE_WORDS(x,se,i0,i1);
|
|
return x;
|
|
}
|
|
weak_alias (__floorl, floorl)
|