minix/lib/nbsd_libc/arch/mips/gen/modf.S
Gianluca Guida b6cbf7203b Import unmodified NetBSD libc in trunk
This patch imports the unmodified current version of NetBSD libc.
The NetBSD includes are in /nbsd_include, while the libc code itself is 
split between lib/nbsd_libc and common/lib/libc.
2011-02-14 19:36:03 +00:00

75 lines
2.8 KiB
ArmAsm

/* $NetBSD: modf.S,v 1.11 2009/12/14 01:07:42 matt Exp $ */
/*-
* Copyright (c) 1991, 1993, 1995
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Ralph Campbell.
*
* 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.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
#include <mips/asm.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
RCSID("from: @(#)modf.s 8.1 (Berkeley) 6/4/93")
#else
RCSID("$NetBSD: modf.S,v 1.11 2009/12/14 01:07:42 matt Exp $")
#endif
#endif /* LIBC_SCCS and not lint */
/*
* double modf(val, iptr)
* double val, *iptr;
* returns: xxx and n (in *iptr) where val == n.xxx
*/
LEAF(modf)
cfc1 t0, $31 # get the control register
li.d $f2, 4503599627370496e0 # f2 <- 2^52
or t1, t0, 0x3 # set rounding mode to round to zero
xor t1, t1, 0x2 # (i.e., 01)
ctc1 t1, $31
mov.d $f0, $f12 # f0 <- f12
abs.d $f4, $f12 # f4 <- |f12|
c.olt.d $f4, $f2 # f4 ? < f2
bc1f 1f # leave f0 alone if Nan, infinity
# or >=2^52
c.eq.d $f12,$f4 # was f12 positive ?
add.d $f4,$f2,$f4 # round off to integer
bc1f 2f # No -> will have to negate result
sub.d $f0,$f4,$f2 # Remove fudge factor
j 1f # integer fraction got
2:
sub.d $f0,$f2,$f4 # Remove fudge factor and negate
1:
ctc1 t0, $31 # restore old rounding mode
s.d $f0, 0(a2) # save the integer part
sub.d $f0, $f12, $f0 # subtract val - integer part
j ra
END(modf)