freebsd-skq/lib/msun/i387/s_remquo.S
2005-03-25 04:40:44 +00:00

63 lines
2.0 KiB
ArmAsm

/*-
* 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("$FreeBSD$");
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