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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

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# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR

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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