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#
# Copyright (c) 2005 Jakub Jermar
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
#   documentation and/or other materials provided with the distribution.
# - The name of the author may not be used to endorse or promote products
#   derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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#include <arch/context_offset.h>

/**
 * Both context_save_arch() and context_restore_arch() are
 * leaf-optimized procedures. This kind of optimization
 * is very important and prevents any implicit window
 * spill/fill/clean traps in these very core kernel
 * functions.
 */
    
#include <arch/context_offset.h>

.text   

.global context_save_arch
.global context_restore_arch

context_save_arch:
    CONTEXT_SAVE_ARCH_CORE %o0
    retl
    mov 1, %o0      ! context_save_arch returns 1

context_restore_arch:
    #
    # Flush all active windows.
    # This is essential, because CONTEXT_LOAD overwrites
    # %sp of CWP - 1 with the value written to %fp of CWP.
    # Flushing all active windows mitigates this problem
    # as CWP - 1 becomes the overlap window.
    #
    flushw
    
    CONTEXT_RESTORE_ARCH_CORE %o0
    retl
    xor %o0, %o0, %o0   ! context_restore_arch returns 0