diff options
Diffstat (limited to 'usr/src/lib/libm/common/m9x/nearbyintl.c')
| -rw-r--r-- | usr/src/lib/libm/common/m9x/nearbyintl.c | 186 |
1 files changed, 186 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/m9x/nearbyintl.c b/usr/src/lib/libm/common/m9x/nearbyintl.c new file mode 100644 index 0000000000..0c1148728b --- /dev/null +++ b/usr/src/lib/libm/common/m9x/nearbyintl.c @@ -0,0 +1,186 @@ +/* + * 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 |