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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#if defined(ELFOBJ)
#pragma weak nearbyintl = __nearbyintl
#endif
#include "libm.h"
#include "fma.h"
#include "fenv_inlines.h"
#if defined(__sparc)
static union {
unsigned i;
float f;
} snan = { 0x7f800001 };
long double
__nearbyintl(long double x) {
union {
unsigned i[4];
long double q;
} xx;
unsigned hx, sx, i, frac;
unsigned int fsr;
int rm, j;
volatile float dummy;
xx.q = x;
sx = xx.i[0] & 0x80000000;
hx = xx.i[0] & ~0x80000000;
/* handle trivial cases */
if (hx >= 0x406f0000) { /* x is nan, inf, or already integral */
/* check for signaling nan */
if ((hx > 0x7fff0000 || (hx == 0x7fff0000 &&
(xx.i[1] | xx.i[2] | xx.i[3]))) && !(hx & 0x8000)) {
dummy = snan.f;
dummy += snan.f;
xx.i[0] = sx | hx | 0x8000;
}
return (xx.q);
} else if ((hx | xx.i[1] | xx.i[2] | xx.i[3]) == 0) /* x is zero */
return (x);
/* get the rounding mode */
__fenv_getfsr32(&fsr);
rm = fsr >> 30;
/* flip the sense of directed roundings if x is negative */
if (sx)
rm ^= rm >> 1;
/* handle |x| < 1 */
if (hx < 0x3fff0000) {
if (rm == FSR_RP || (rm == FSR_RN && (hx >= 0x3ffe0000 &&
((hx & 0xffff) | xx.i[1] | xx.i[2] | xx.i[3]))))
xx.i[0] = sx | 0x3fff0000;
else
xx.i[0] = sx;
xx.i[1] = xx.i[2] = xx.i[3] = 0;
return (xx.q);
}
/* round x at the integer bit */
j = 0x406f - (hx >> 16);
if (j >= 96) {
i = 1 << (j - 96);
frac = ((xx.i[0] << 1) << (127 - j)) | (xx.i[1] >> (j - 96));
if ((xx.i[1] & (i - 1)) | xx.i[2] | xx.i[3])
frac |= 1;
if (!frac)
return (x);
xx.i[1] = xx.i[2] = xx.i[3] = 0;
xx.i[0] &= ~(i - 1);
if (rm == FSR_RP || (rm == FSR_RN && (frac > 0x80000000u ||
(frac == 0x80000000 && (xx.i[0] & i)))))
xx.i[0] += i;
} else if (j >= 64) {
i = 1 << (j - 64);
frac = ((xx.i[1] << 1) << (95 - j)) | (xx.i[2] >> (j - 64));
if ((xx.i[2] & (i - 1)) | xx.i[3])
frac |= 1;
if (!frac)
return (x);
xx.i[2] = xx.i[3] = 0;
xx.i[1] &= ~(i - 1);
if (rm == FSR_RP || (rm == FSR_RN && (frac > 0x80000000u ||
(frac == 0x80000000 && (xx.i[1] & i))))) {
xx.i[1] += i;
if (xx.i[1] == 0)
xx.i[0]++;
}
} else if (j >= 32) {
i = 1 << (j - 32);
frac = ((xx.i[2] << 1) << (63 - j)) | (xx.i[3] >> (j - 32));
if (xx.i[3] & (i - 1))
frac |= 1;
if (!frac)
return (x);
xx.i[3] = 0;
xx.i[2] &= ~(i - 1);
if (rm == FSR_RP || (rm == FSR_RN && (frac > 0x80000000u ||
(frac == 0x80000000 && (xx.i[2] & i))))) {
xx.i[2] += i;
if (xx.i[2] == 0)
if (++xx.i[1] == 0)
xx.i[0]++;
}
} else {
i = 1 << j;
frac = (xx.i[3] << 1) << (31 - j);
if (!frac)
return (x);
xx.i[3] &= ~(i - 1);
if (rm == FSR_RP || (rm == FSR_RN && (frac > 0x80000000u ||
(frac == 0x80000000 && (xx.i[3] & i))))) {
xx.i[3] += i;
if (xx.i[3] == 0)
if (++xx.i[2] == 0)
if (++xx.i[1] == 0)
xx.i[0]++;
}
}
return (xx.q);
}
#elif defined(__x86)
/* inline template */
extern long double frndint(long double);
long double
__nearbyintl(long double x) {
long double z;
unsigned oldcwsw, cwsw;
/* save the control and status words, mask the inexact exception */
__fenv_getcwsw(&oldcwsw);
cwsw = oldcwsw | 0x00200000;
__fenv_setcwsw(&cwsw);
z = frndint(x);
/*
* restore the control and status words, preserving all but the
* inexact flag
*/
__fenv_getcwsw(&cwsw);
oldcwsw |= (cwsw & 0x1f);
__fenv_setcwsw(&oldcwsw);
return (z);
}
#else
#error Unknown architecture
#endif
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