33 lines
721 B
ArmAsm
33 lines
721 B
ArmAsm
|
.define .aar
|
||
|
.sect .text
|
||
|
.sect .rom
|
||
|
.sect .data
|
||
|
.sect .bss
|
||
|
.sect .text
|
||
|
|
||
|
.aar: ! (on entry d0 contains the integer size in the descriptor)
|
||
|
|
||
|
cmp.l #4, d0
|
||
|
beq 9f
|
||
|
move.l #EILLINS, -(sp)
|
||
|
jmp (.fatal)
|
||
|
9:
|
||
|
! register usage:
|
||
|
! a0: descriptor address
|
||
|
! a1: return address
|
||
|
! d0: index
|
||
|
|
||
|
! The address is calculated by taking the relative index
|
||
|
! (index - lower bound), multiplying that with the element
|
||
|
! size and adding the result to the array base address.
|
||
|
|
||
|
move.l (sp)+, a1 ! return address
|
||
|
move.l (sp)+, a0 ! descriptor address
|
||
|
move.l (sp)+, d0 ! index
|
||
|
sub.l (a0), d0 ! relative index
|
||
|
muls.l (8,a0), d0
|
||
|
move.l (sp)+, a0 ! array base address
|
||
|
add.l d0, a0 ! address of array element
|
||
|
jmp (a1) ! return
|
||
|
.align 2
|