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/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
*/
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
.file "nextafter.s"
#include "libm.h"
LIBM_ANSI_PRAGMA_WEAK(nextafter,function)
.weak _nextafter
.type _nextafter,@function
_nextafter = __nextafter
#include "libm_protos.h"
.data
.align 8
Fmin: .long 0x1,0x0
ftmp: .long 0,0 /// WILL WRITE INTO
ENTRY(nextafter)
pushl %ebp
movl %esp,%ebp
fldl 16(%ebp) / y
subl $8,%esp
fldl 8(%ebp) / load x
fucom / x : y
fstsw %ax
sahf
jp .NaN
je .equal
fstp %st(1) / x
ja .bigger
/ x < y
ftst
movl $1,%ecx /// Fmin
movl %ecx,-8(%ebp)
movl $0,%ecx /// Fmin+4
movl %ecx,-4(%ebp)
fnstsw %ax
sahf
je .final
ja .addulp
jb .subulp
.bigger:
/ x > y
ftst
movl $1,%ecx /// Fmin
movl %ecx,-8(%ebp)
movl $0,%ecx /// Fmin+4
xorl $0x80000000,%ecx
movl %ecx,-4(%ebp)
fnstsw %ax
sahf
je .final
jb .addulp
.subulp:
movl 8(%ebp),%eax / low x
movl 12(%ebp),%ecx / high x
subl $1,%eax / low x - ulp
movl %eax,-8(%ebp)
sbbl $0x0,%ecx
movl %ecx,-4(%ebp)
jmp .final
.addulp:
movl 8(%ebp),%eax / low x
movl 12(%ebp),%ecx / high x
addl $1,%eax / low x + ulp
movl %eax,-8(%ebp)
adcl $0x0,%ecx
movl %ecx,-4(%ebp)
.final:
fstp %st(0)
fldl -8(%ebp)
andl $0x7ff00000,%ecx
jz .underflow
cmpl $0x7ff00000,%ecx
je .overflow
jmp .return
.overflow:
PIC_SETUP(1)
pushl $46
fstp %st(0) / stack empty
pushl -4(%ebp)
pushl -8(%ebp)
pushl -4(%ebp)
pushl -8(%ebp)
call PIC_F(_SVID_libm_err)
addl $20,%esp
PIC_WRAPUP
jmp .return
.underflow:
PIC_SETUP(2)
fldl PIC_L(Fmin)
fmul %st(0),%st
fstpl PIC_L(ftmp) / create underflow signal
PIC_WRAPUP
jmp .return
.equal:
fstp %st(0) / C99 says to return y when x == y
jmp .return
.NaN:
faddp %st,%st(1) / x+y,x
.return:
fwait
leave
ret
.align 4
SET_SIZE(nextafter)
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