;  ###----------------------------------------------------------------###
;  # file	: exc012.u						#
;  # date	: Mar 26 1996						#
;  # descr.	: functional test for mips				#
;  ###----------------------------------------------------------------###

	;  ###--------------------------------------------------------###
	;  #   exceptions :						#
	;  #     - data address miss alignment (storing a half-word)	#
	;  ###--------------------------------------------------------###

adr		.equ	0x40000050
data		.equ	0x616b			; data

		.org	0x00400000
		.start	init

init:
		loadi	r31, back_from_exception
		loadi	r1 , adr		; half word's address in r1
		loadi	r2 , data		; data in r2
		loadi	r3 , data		; same data in r3
		loadi	r4 , data ^ 0xffffffff	; complemented data in r4

	;  ###--------------------------------------------------------###
	;  #   store the word to initialize the memory location		#
	;  ###--------------------------------------------------------###

		sw	 r2, 0 (r1 )

	;  ###--------------------------------------------------------###
	;  #   store half-word at a miss aligned address		#
	;  ###--------------------------------------------------------###

		sh	 r4, 1 (r1 )		; EXCEPTION (alignment)

	;  ###--------------------------------------------------------###
	;  #   after returning from exception, read the memory 		#
	;  # location and check that the faulty store word has not 	#
	;  # modified the memory					#
	;  ###--------------------------------------------------------###

back_from_exception:
		lw	r5 , 0 (r1 )

	;  ###--------------------------------------------------------###
	;  #   if the read word is correct branch to good		#
	;  ###--------------------------------------------------------###

		bne	r5, r3,bad
		nop
		j	good
		nop

		.org	0x004000d0
good:		j	good
		nop
bad:		j	bad
		nop
		.end