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; ###----------------------------------------------------------------###
; # file : exc024.s #
; # date : Mar 26 1996 #
; # descr. : functional test for mips #
; ###----------------------------------------------------------------###
; ###--------------------------------------------------------###
; # exceptions : #
; # - instruction bus error #
; ###--------------------------------------------------------###
xcode_mask .equ 0x3C ; exc mask
xcode_ibe .equ 0x18 ; instruction bus error
.org 0x80000080
.start it_handler
; ###--------------------------------------------------------###
; # interrupt and exception handler #
; ###--------------------------------------------------------###
it_handler:
sw r29, 0 (r30)
sw r28, 4 (r30)
mfc0 r29,cause
nop
addiu r28,r0,xcode_mask
and r29, r29, r28 ; instruction bus error ?
addiu r27,r0,xcode_ibe
bne r29,r27, other_causes
nop
lw r29, 0 (r30)
lw r28, 4 (r30)
restore_return_adr:
j return
nop
other_causes: j other_causes
nop
; ###--------------------------------------------------------###
; # return to the interrupted program #
; ###--------------------------------------------------------###
.org 0x800000d0
return:
rfe
jr r31
.end
|
