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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.
*/
#pragma weak __lrintl = lrintl
#include <sys/isa_defs.h> /* _ILP32 */
#include "libm.h"
#if defined(_ILP32)
#if defined(__sparc)
#include "fma.h"
#include "fenv_inlines.h"
long
lrintl(long double x) {
union {
unsigned int i[4];
long double q;
} xx;
union {
unsigned int i;
float f;
} tt;
unsigned int hx, sx, frac, l, 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 > 0x401e0000) { /* |x| > 2^31 + ... or x is nan */
/* convert an out-of-range float */
tt.i = sx | 0x7f000000;
return ((long) tt.f);
} else if ((hx | xx.i[1] | xx.i[2] | xx.i[3]) == 0) /* x is zero */
return (0L);
/* 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) {
dummy = 1.0e30F; /* x is nonzero, so raise inexact */
dummy += 1.0e-30F;
if (rm == FSR_RP || (rm == FSR_RN && (hx >= 0x3ffe0000 &&
((hx & 0xffff) | xx.i[1] | xx.i[2] | xx.i[3]))))
return (sx ? -1L : 1L);
return (0L);
}
/* extract the integer and fractional parts of x */
j = 0x406f - (hx >> 16); /* 91 <= j <= 112 */
xx.i[0] = 0x10000 | (xx.i[0] & 0xffff);
if (j >= 96) { /* 96 <= j <= 112 */
l = xx.i[0] >> (j - 96);
frac = ((xx.i[0] << 1) << (127 - j)) | (xx.i[1] >> (j - 96));
if (((xx.i[1] << 1) << (127 - j)) | xx.i[2] | xx.i[3])
frac |= 1;
} else { /* 91 <= j <= 95 */
l = (xx.i[0] << (96 - j)) | (xx.i[1] >> (j - 64));
frac = (xx.i[1] << (96 - j)) | (xx.i[2] >> (j - 64));
if ((xx.i[2] << (96 - j)) | xx.i[3])
frac |= 1;
}
/* round */
if (frac && (rm == FSR_RP || (rm == FSR_RN && (frac > 0x80000000U ||
(frac == 0x80000000 && (l & 1))))))
l++;
/* check for result out of range (note that z is |x| at this point) */
if (l > 0x80000000U || (l == 0x80000000U && !sx)) {
tt.i = sx | 0x7f000000;
return ((long) tt.f);
}
/* raise inexact if need be */
if (frac) {
dummy = 1.0e30F;
dummy += 1.0e-30F;
}
/* negate result if need be */
if (sx)
l = -l;
return ((long) l);
}
#elif defined(__x86)
long
lrintl(long double x) {
/*
* Note: The following code works on x86 (in the default rounding
* precision mode), but one ought to just use the fistpl instruction
* instead.
*/
union {
unsigned i[3];
long double e;
} xx, yy;
int ex;
xx.e = x;
ex = xx.i[2] & 0x7fff;
if (ex < 0x403e) { /* |x| < 2^63 */
/* add and subtract a power of two to round x to an integer */
yy.i[2] = (xx.i[2] & 0x8000) | 0x403e;
yy.i[1] = 0x80000000;
yy.i[0] = 0;
x = (x + yy.e) - yy.e;
}
/* now x is nan, inf, or integral */
return ((long) x);
}
#else
#error Unknown architecture
#endif /* defined(__sparc) || defined(__x86) */
#else
#error Unsupported architecture
#endif /* defined(_ILP32) */
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