| /*- |
| * Copyright (c) 2005 David Schultz <das@FreeBSD.ORG> |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND |
| * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS |
| * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY |
| * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| /* |
| * Based on public-domain remainder routine by J.T. Conklin <jtc@NetBSD.org>. |
| */ |
| |
| #include <machine/asm.h> |
| __FBSDID("$FreeBSD: src/lib/msun/i387/s_remquo.S,v 1.1 2005/03/25 04:40:44 das Exp $"); |
| |
| ENTRY(remquo) |
| fldl 12(%esp) |
| fldl 4(%esp) |
| 1: fprem1 |
| fstsw %ax |
| sahf |
| jp 1b |
| fstp %st(1) |
| /* Extract the three low-order bits of the quotient from C0,C3,C1. */ |
| shrl $6,%eax |
| movl %eax,%ecx |
| andl $0x108,%eax |
| rorl $7,%eax |
| orl %eax,%ecx |
| roll $4,%eax |
| orl %ecx,%eax |
| andl $7,%eax |
| /* Negate the quotient bits if x*y<0. Avoid using an unpredictable branch. */ |
| movl 16(%esp),%ecx |
| xorl 8(%esp),%ecx |
| sarl $16,%ecx |
| sarl $16,%ecx |
| xorl %ecx,%eax |
| andl $1,%ecx |
| addl %ecx,%eax |
| /* Store the quotient and return. */ |
| movl 20(%esp),%ecx |
| movl %eax,(%ecx) |
| ret |
