common/m9x/modfl.c

25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis/*
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * CDDL HEADER START
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis *
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * The contents of this file are subject to the terms of the
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Common Development and Distribution License (the "License").
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * You may not use this file except in compliance with the License.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis *
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * or http://www.opensolaris.org/os/licensing.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * See the License for the specific language governing permissions
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * and limitations under the License.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis *
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * When distributing Covered Code, include this CDDL HEADER in each
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * If applicable, add the following below this CDDL HEADER, with the
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * fields enclosed by brackets "[]" replaced with your own identifying
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * information: Portions Copyright [yyyy] [name of copyright owner]
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis *
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * CDDL HEADER END
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis/*
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis/*
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis * Use is subject to license terms.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis#pragma weak modfl = __modfl
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis#include "libm.h"
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis#if defined(__sparc)
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtislong double
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis__modfl(long double x, long double *iptr) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    union {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        unsigned i[4];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        long double q;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    } xx, yy;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    unsigned hx, s;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    xx.q = x;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    hx = xx.i[0] & ~0x80000000;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    if (hx >= 0x406f0000) { /* x is NaN, infinite, or integral */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        *iptr = x;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        if (hx < 0x7fff0000 || (hx == 0x7fff0000 &&
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis            (xx.i[1] | xx.i[2] | xx.i[3]) == 0)) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis            xx.i[0] &= 0x80000000;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis            xx.i[1] = xx.i[2] = xx.i[3] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        return (xx.q);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    if (hx < 0x3fff0000) {  /* |x| < 1 */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        xx.i[0] &= 0x80000000;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        xx.i[1] = xx.i[2] = xx.i[3] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        *iptr = xx.q;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        return (x);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    /* split x at the binary point */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    s = xx.i[0] & 0x80000000;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    if (hx < 0x40100000) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[0] = xx.i[0] & ~((1 << (0x400f - (hx >> 16))) - 1);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[1] = yy.i[2] = yy.i[3] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    } else if (hx < 0x40300000) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[0] = xx.i[0];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[1] = xx.i[1] & ~((1 << (0x402f - (hx >> 16))) - 1);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[2] = yy.i[3] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    } else if (hx < 0x40500000) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[0] = xx.i[0];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[1] = xx.i[1];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[2] = xx.i[2] & ~((1 << (0x404f - (hx >> 16))) - 1);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[3] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    } else {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[0] = xx.i[0];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[1] = xx.i[1];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[2] = xx.i[2];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[3] = xx.i[3] & ~((1 << (0x406f - (hx >> 16))) - 1);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    *iptr = yy.q;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    /*
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis     * we could implement the following more efficiently than by using
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis     * software emulation of fsubq, but we'll do it this way for now
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis     * (and hope hardware support becomes commonplace)
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis     */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    xx.q -= yy.q;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    xx.i[0] = (xx.i[0] & ~0x80000000) | s;  /* keep sign of x */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    return (xx.q);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis}
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis#elif defined(__x86)
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtislong double
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis__modfl(long double x, long double *iptr) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    union {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        unsigned i[3];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        long double e;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    } xx, yy;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    unsigned hx, s;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    /*
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis     * It might be faster to use one of the x86 fpops instead of
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis     * the following.
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis     */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    xx.e = x;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    hx = xx.i[2] & 0x7fff;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    if (hx >= 0x403e) { /* x is NaN, infinite, or integral */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        *iptr = x;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        if (hx < 0x7fff || (hx == 0x7fff &&
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis            ((xx.i[1] << 1) | xx.i[0]) == 0)) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis            xx.i[2] &= 0x8000;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis            xx.i[1] = xx.i[0] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        return (xx.e);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    if (hx < 0x3fff) {  /* |x| < 1 */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        xx.i[2] &= 0x8000;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        xx.i[1] = xx.i[0] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        *iptr = xx.e;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        return (x);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    /* split x at the binary point */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    s = xx.i[2] & 0x8000;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    yy.i[2] = xx.i[2];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    if (hx < 0x401f) {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[1] = xx.i[1] & ~((1 << (0x401e - hx)) - 1);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[0] = 0;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    } else {
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[1] = xx.i[1];
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis        yy.i[0] = xx.i[0] & ~((1 << (0x403e - hx)) - 1);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    }
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    *iptr = yy.e;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    xx.e -= yy.e;
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    xx.i[2] = (xx.i[2] & ~0x8000) | s;  /* keep sign of x */
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis    return (xx.e);
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis}
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis#else
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis#error Unknown architecture
25c28e83beb90e7c80452a7c818c5e6f73a07dc8Piotr Jasiukajtis#endif