sbrk.S revision 240152 
1139749Simp/*-
285810Sobrien * Copyright (c) 1990 The Regents of the University of California.
385810Sobrien * All rights reserved.
485810Sobrien *
585810Sobrien * This code is derived from software contributed to Berkeley by
685810Sobrien * William Jolitz.
785810Sobrien *
885810Sobrien * Redistribution and use in source and binary forms, with or without
985810Sobrien * modification, are permitted provided that the following conditions
1085810Sobrien * are met:
1185810Sobrien * 1. Redistributions of source code must retain the above copyright
1285810Sobrien *    notice, this list of conditions and the following disclaimer.
1385810Sobrien * 2. Redistributions in binary form must reproduce the above copyright
1485810Sobrien *    notice, this list of conditions and the following disclaimer in the
1585810Sobrien *    documentation and/or other materials provided with the distribution.
1685810Sobrien * 4. Neither the name of the University nor the names of its contributors
1785810Sobrien *    may be used to endorse or promote products derived from this software
1885810Sobrien *    without specific prior written permission.
1985810Sobrien *
2085810Sobrien * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2185810Sobrien * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2285810Sobrien * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2385810Sobrien * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2485810Sobrien * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2585810Sobrien * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2685810Sobrien * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2785810Sobrien * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2885810Sobrien * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2985810Sobrien * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
3085810Sobrien * SUCH DAMAGE.
3185810Sobrien */
3285810Sobrien
3385810Sobrien#if defined(SYSLIBC_SCCS) && !defined(lint)
3485810Sobrien	.asciz "@(#)sbrk.s	5.1 (Berkeley) 4/23/90"
3585810Sobrien#endif /* SYSLIBC_SCCS and not lint */
3685810Sobrien#include <machine/asm.h>
3785810Sobrien__FBSDID("$FreeBSD: head/lib/libc/i386/sys/sbrk.S 240152 2012-09-05 21:41:05Z jilles $");
38170837Smarius
3985810Sobrien#include "SYS.h"
4085810Sobrien
4185810Sobrien	.globl	CNAME(_end)
42	.globl	HIDENAME(minbrk)
43	.globl	HIDENAME(curbrk)
44
45	.data
46HIDENAME(minbrk):	.long	CNAME(_end)
47HIDENAME(curbrk):	.long	CNAME(_end)
48	.text
49
50ENTRY(sbrk)
51#ifdef PIC
52	movl	4(%esp),%ecx
53	PIC_PROLOGUE
54	movl	PIC_GOT(HIDENAME(curbrk)),%edx
55	movl	(%edx),%eax
56	PIC_EPILOGUE
57	testl	%ecx,%ecx
58	jz	back
59	addl	%eax,4(%esp)
60	mov	$SYS_break,%eax
61	KERNCALL
62	jb	HIDENAME(cerror)
63	PIC_PROLOGUE
64	movl	PIC_GOT(HIDENAME(curbrk)),%edx
65	movl	(%edx),%eax
66	addl	%ecx,(%edx)
67	PIC_EPILOGUE
68back:
69	ret
70
71#else /* !PIC */
72
73	movl	4(%esp),%ecx
74	movl	HIDENAME(curbrk),%eax
75	testl	%ecx,%ecx
76	jz	back
77	addl	%eax,4(%esp)
78	mov	$SYS_break,%eax
79	KERNCALL
80	jb	HIDENAME(cerror)
81	movl	HIDENAME(curbrk),%eax
82	addl	%ecx,HIDENAME(curbrk)
83back:
84	ret
85#endif /* PIC */
86END(sbrk)
87
88	.section .note.GNU-stack,"",%progbits
89