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      1 /*	$NetBSD: brk.S,v 1.19 2013/09/12 15:36:15 joerg Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1990 The Regents of the University of California.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to Berkeley by
      8  * the Systems Programming Group of the University of Utah Computer
      9  * Science Department.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  */
     35 
     36 #include "SYS.h"
     37 
     38 #if defined(LIBC_SCCS) && !defined(lint)
     39 #if 0
     40 	RCSID("from: @(#)brk.s	5.1 (Berkeley) 5/12/90")
     41 #else
     42 	RCSID("$NetBSD: brk.S,v 1.19 2013/09/12 15:36:15 joerg Exp $")
     43 #endif
     44 #endif /* LIBC_SCCS and not lint */
     45 
     46 	.globl	_end
     47 	.globl	_C_LABEL(__minbrk)
     48 	.hidden	_C_LABEL(__minbrk)
     49 	.globl	_C_LABEL(__curbrk)
     50 	.hidden	_C_LABEL(__curbrk)
     51 
     52 #ifdef WEAK_ALIAS
     53 WEAK_ALIAS(brk, _brk)
     54 #endif
     55 
     56 	.data
     57 _C_LABEL(__minbrk):
     58 	.long	_end
     59 
     60 	.text
     61 
     62 ENTRY(_brk)
     63 #ifdef __PIC__
     64 	LEA_LCL(_C_LABEL(__minbrk),%a1)
     65 	movl	(%a1),%a1
     66 #else
     67 	movl	_C_LABEL(__minbrk),%a1
     68 #endif
     69 	cmpl	4(%sp),%a1
     70 	jls	ok
     71 	movl	%a1,4(%sp)
     72 ok:
     73 	SYSTRAP(break)
     74 	jcs	CERROR
     75 #ifdef __PIC__
     76 	LEA_LCL(_C_LABEL(__curbrk),%a0)
     77 	movl	%a1,(%a0)
     78 #else
     79 	movl	%a1,_C_LABEL(__curbrk)
     80 #endif
     81 	clrl	%d0
     82 	rts
     83 END(_brk)
     84