;--------------------------------------------------------------------------
;  atomic_flag_test_and_set.s
;
;  Copyright (C) 2020, Philipp Klaus Krause
;
;  This library is free software; you can redistribute it and/or modify it
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;  Free Software Foundation; either version 2, or (at your option) any
;  later version.
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;  This library is distributed in the hope that it will be useful,
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;  As a special exception, if you link this library with other files,
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;  this library does not by itself cause the resulting executable to
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;--------------------------------------------------------------------------

	.area   _CODE

	.globl _atomic_flag_test_and_set

_atomic_flag_test_and_set:
	ld	hl, 2 (sp)
	xor a, a
	srl	(hl)
	ccf
	rla
	ld	l, a
	ret

