#
# 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
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#include <libarch/context_offset.h>

.text

.global context_save
.global context_restore

context_save:
	#
	# We rely on the kernel to flush our active register windows to memory
	# should a thread switch occur.
	#
	CONTEXT_SAVE_ARCH_CORE %o0
	retl
	mov 1, %o0		! context_save_arch returns 1

context_restore:
	#
	# Flush all active windows.
	# This is essential, because CONTEXT_RESTORE_ARCH_CORE 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