usr/src/lib/libc/quad/ashldi3.c

/*-
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This software was developed by the Computer Systems Engineering group
 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
 * contributed to Berkeley.
 *
 * %sccs.include.redist.c%
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)ashldi3.c   8.1 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */

#include "quad.h"

/*
 * Shift a (signed) quad value left (arithmetic shift left).
 * This is the same as logical shift left!
 */
quad_t
__ashldi3(a, shift)
        quad_t a;
        qshift_t shift;
{
        union uu aa;

        aa.q = a;
        if (shift >= LONG_BITS) {
                aa.ul[H] = shift >= QUAD_BITS ? 0 :
                    aa.ul[L] << (shift - LONG_BITS);
                aa.ul[L] = 0;
        } else if (shift > 0) {
                aa.ul[H] = (aa.ul[H] << shift) |
                    (aa.ul[L] >> (LONG_BITS - shift));
                aa.ul[L] <<= shift;
        }
        return (aa.q);
}