/*
* 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 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
.file "_stack_grow.s"
#include "SYS.h"
#include <../assym.h>
/*
* void *
* _stack_grow(void *addr)
* {
* uintptr_t base = (uintptr_t)curthread->ul_ustack.ss_sp;
* size_t size = curthread->ul_ustack.ss_size;
*
* if (size > (uintptr_t)addr - (base - STACK_BIAS))
* return (addr);
*
* if (size == 0)
* return (addr);
*
* if (size > %sp - (base - STACK_BIAS))
* %sp = base - STACK_BIAS - STACK_ALIGN;
*
* *((char *)(base - 1));
*
* _lwp_kill(_lwp_self(), SIGSEGV);
* }
*/
#if defined(__sparcv9)
#define PN ,pn %xcc,
#else
#define PN
#endif
/*
* o0: address to which the stack will be grown (biased)
*/
ENTRY(_stack_grow)
ldn [%g7 + UL_USTACK + SS_SP], %o1
ldn [%g7 + UL_USTACK + SS_SIZE], %o2
sub %o1, STACK_BIAS, %o3
sub %o0, %o3, %o4
cmp %o2, %o4
bleu PN 1f
tst %o2
retl
nop
1:
/*
* If the stack size is 0, stack checking is disabled.
*/
bnz PN 2f
nop
retl
nop
2:
/*
* Move the stack pointer outside the stack bounds if it isn't already.
*/
sub %sp, %o3, %o4
cmp %o2, %o4
bleu PN 3f
nop
sub %o3, STACK_ALIGN, %sp
3:
/*
* Dereference an address in the guard page.
*/
ldub [%o1 - 1], %g0
/*
* If the above load doesn't raise a SIGSEGV then do it ourselves.
*/
SYSTRAP_RVAL1(lwp_self)
mov SIGSEGV, %o1
SYSTRAP_RVAL1(lwp_kill)
/*
* We should never get here; explode if we do.
*/
illtrap
SET_SIZE(_stack_grow)