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#------------------------------------------------------------------------------
#
# Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
# This program and the accompanying materials
# are licensed and made available under the terms and conditions of the BSD License
# which accompanies this distribution. The full text of the license may be found at
# http://opensource.org/licenses/bsd-license.php.
#
# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
#
# Module Name:
#
# Alloca.S
#
# Abstract:
#
# Implementation for allocation of automatically reclaimed memory, which is
# used to allocate space off the runtime stack.
# (NOTE: There is a assumption in this code that the page size equal to 4K)
#
#------------------------------------------------------------------------------
.686:
.code:
ASM_GLOBAL ASM_PFX(_alloca)
#------------------------------------------------------------------------------
#
# void __cdecl _alloca (unsigned size)
#
#------------------------------------------------------------------------------
ASM_PFX(_alloca):
pushl %ecx
cmpl $0x1000, %eax
leal 8(%esp), %ecx
jb LastPage
ProbePages:
subl $0x1000, %ecx
subl $0x1000, %eax
testl %eax, 0(%ecx)
cmpl $0x1000, %eax
jae ProbePages
LastPage:
subl %eax, %ecx
movl %esp, %eax
testl %eax, 0(%ecx)
movl %ecx, %esp
movl 0(%eax), %ecx
movl 4(%eax), %eax
pushl %eax
ret
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