freebsd-nq/lib/libc/powerpcspe/gen/fabs.S
Justin Hibbits 28c20ad06c Fix fabs(3) for powerpcspe, this time for real
SPE ABI uses the soft-float ABI, which splits doubles into two words.  As such,
fabs(3) cannot work on a double directly.  It's too costly to convert the
argument pair into a single double to use efdabs, so clear the top bit of the
high word, which is the sign bit.
2018-07-26 14:42:20 +00:00

40 lines
1.5 KiB
ArmAsm

/*
* Copyright (c) 2016 Justin Hibbits
* 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.
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
/*
* double fabs(double)
*/
ENTRY(fabs)
/* arg is split in two words, clear sign bit only, in r3. */
clrlwi %r3,%r3,1
blr
END(fabs)
.section .note.GNU-stack,"",%progbits