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|
; ###----------------------------------------------------------------###
; # file : mftc0_00.s #
; # date : Mar 26 1996 #
; # descr. : functional test for mips #
; ###----------------------------------------------------------------###
; ###--------------------------------------------------------###
; # exceptions : #
; # - break #
; ###--------------------------------------------------------###
value .equ 0x12344444
ill_codop .equ 0x28
mask .equ 0x3C
.org 0x80000080
.start it_handler
; ###--------------------------------------------------------###
; # interrupt and exception handler #
; ###--------------------------------------------------------###
it_handler:
sw r29, 0 (r30)
sw r28, 4 (r30)
;addiu r28, r0, mask
;mfc0 r29, cause
;nop
;and r29, r29, r28
;addiu r28, r0, ill_codop
;bne r28, r29, not_good
loadi r28, value
loadi r29, value
mtc0 r28, cause
nop
mtc0 r29, status
nop
mfc0 r29, cause
nop
mfc0 r28, status
nop
bne r28, r29, not_good
lw r29, 0 (r30)
lw r28, 4 (r30)
; ###--------------------------------------------------------###
; # restore return address before returning (from EXCEPTION) #
; # to the user program (address must be saved by the user #
; # prior to the EXCEPTION in epc) #
; ###--------------------------------------------------------###
restore_return_adr:
mfc0 r31, epc
nop
addiu r31, r31, 8
jr r31
rfe
not_good:
mfc0 r31, epc
nop
addiu r31, r31, 4
jr r31
rfe
.end
|
