diff options
Diffstat (limited to 'usr/src/lib/libm/common/m9x/roundl.c')
| -rw-r--r-- | usr/src/lib/libm/common/m9x/roundl.c | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/m9x/roundl.c b/usr/src/lib/libm/common/m9x/roundl.c new file mode 100644 index 0000000000..957b93251b --- /dev/null +++ b/usr/src/lib/libm/common/m9x/roundl.c @@ -0,0 +1,166 @@ +/* + * 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 roundl = __roundl +#endif + +#include "libm.h" + +#if defined(__sparc) +long double +roundl(long double x) { + union { + unsigned i[4]; + long double q; + } xx; + unsigned hx, sx, v; + int j; + + xx.q = x; + sx = xx.i[0] & 0x80000000; + hx = xx.i[0] & ~0x80000000; + + /* handle trivial cases */ + if (hx >= 0x406f0000) /* |x| >= 2^112 + ... or x is nan */ + return (hx >= 0x7fff0000 ? x + x : x); + + /* handle |x| < 1 */ + if (hx < 0x3fff0000) { + if (hx >= 0x3ffe0000) + return (sx ? -1.0L : 1.0L); + return (sx ? -0.0L : 0.0L); + } + + xx.i[0] = hx; + j = 0x406f - (hx >> 16); /* 1 <= j <= 112 */ + if (j >= 96) { /* 96 <= j <= 112 */ + v = (1U << (j - 96)) >> 1; + if (v) { + if (xx.i[0] & v) + xx.i[0] += v; + xx.i[0] &= ~(v - 1); + } else if (xx.i[1] & 0x80000000) + ++xx.i[0]; + xx.i[1] = xx.i[2] = xx.i[3] = 0; + } else if (j >= 64) { /* 64 <= j <= 95 */ + v = (1U << (j - 64)) >> 1; + if (v) { + if (xx.i[1] & v) { + xx.i[1] += v; + if (xx.i[1] < v) + ++xx.i[0]; + } + xx.i[1] &= ~(v - 1); + } else if (xx.i[2] & 0x80000000) { + if (++xx.i[1] == 0) + ++xx.i[0]; + } + xx.i[2] = xx.i[3] = 0; + } else if (j >= 32) { /* 32 <= j <= 63 */ + v = (1U << (j - 32)) >> 1; + if (v) { + if (xx.i[2] & v) { + xx.i[2] += v; + if (xx.i[2] < v) { + if (++xx.i[1] == 0) + ++xx.i[0]; + } + } + xx.i[2] &= ~(v - 1); + } else if (xx.i[3] & 0x80000000) { + if (++xx.i[2] == 0) { + if (++xx.i[1] == 0) + ++xx.i[0]; + } + } + xx.i[3] = 0; + } else { /* 1 <= j <= 31 */ + v = 1U << (j - 1); + if (xx.i[3] & v) { + xx.i[3] += v; + if (xx.i[3] < v) { + if (++xx.i[2] == 0) { + if (++xx.i[1] == 0) + ++xx.i[0]; + } + } + } + xx.i[3] &= ~(v - 1); + } + + /* negate result if need be */ + if (sx) + xx.i[0] |= 0x80000000; + return (xx.q); +} +#elif defined(__x86) +long double +roundl(long double x) { + union { + unsigned i[3]; + long double e; + } xx; + int ex, sx, i; + + xx.e = x; + ex = xx.i[2] & 0x7fff; + sx = xx.i[2] & 0x8000; + if (ex < 0x403e) { /* |x| < 2^63 */ + if (ex < 0x3fff) { /* |x| < 1 */ + if (ex >= 0x3ffe) + return (sx ? -1.0L : 1.0L); + return (sx ? -0.0L : 0.0L); + } + + /* round x at the integer bit */ + if (ex < 0x401e) { + i = 1 << (0x401d - ex); + xx.i[1] = (xx.i[1] + i) & ~(i | (i - 1)); + xx.i[0] = 0; + } else { + i = 1 << (0x403d - ex); + xx.i[0] += i; + if (xx.i[0] < i) + xx.i[1]++; + xx.i[0] &= ~(i | (i - 1)); + } + if (xx.i[1] == 0) { + xx.i[2] = sx | ++ex; + xx.i[1] = 0x80000000U; + } + return (xx.e); + } else if (ex < 0x7fff) /* x is integral */ + return (x); + else /* inf or nan */ + return (x + x); +} +#else +#error Unknown architecture +#endif /* defined(__sparc) || defined(__x86) */ |