1#------------------------------------------------------------------------------ 2# 3# Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR> 4# Portions copyright (c) 2011, Apple Inc. All rights reserved.<BR> 5# This program and the accompanying materials 6# are licensed and made available under the terms and conditions of the BSD License 7# which accompanies this distribution. The full text of the license may be found at 8# http://opensource.org/licenses/bsd-license.php. 9# 10# THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, 11# WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. 12# 13# Module Name: 14# 15# InternalSwitchStack.S 16# 17# Abstract: 18# 19# Implementation of a stack switch on IA-32. 20# 21#------------------------------------------------------------------------------ 22 23ASM_GLOBAL ASM_PFX(InternalSwitchStack) 24 25#------------------------------------------------------------------------------ 26# VOID 27# EFIAPI 28# InternalSwitchStack ( 29# IN SWITCH_STACK_ENTRY_POINT EntryPoint, 30# IN VOID *Context1, OPTIONAL 31# IN VOID *Context2, OPTIONAL 32# IN VOID *NewStack 33# ); 34#------------------------------------------------------------------------------ 35ASM_PFX(InternalSwitchStack): 36 pushl %ebp 37 movl %esp, %ebp 38 39 movl 20(%ebp), %esp # switch stack 40 subl $8, %esp 41 42 movl 16(%ebp), %eax 43 movl %eax, 4(%esp) 44 movl 12(%ebp), %eax 45 movl %eax, (%esp) 46 pushl $0 # keeps gdb from unwinding stack 47 jmp *8(%ebp) # call and never return 48 49