ack/mach/m68020/libem/lar.s

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.define .lar
.sect .text
.sect .rom
.sect .data
.sect .bss
.sect .text
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EILLINS=18
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! (on entry d0 contains the integer size in the descriptor)
.lar:
cmp.l #4, d0
beq 9f
move.l #EILLINS, -(sp)
jmp (.fatal)
9:
! register usage:
! a0: descriptor address
! a1: base address
! d0: index
! d1: # bytes / element
! For address calculation; see comment in 'aar.s'.
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move.l (sp)+, d1 ! return address
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move.l (sp)+, a0 ! descriptor address
move.l (sp)+, d0 ! index
move.l (sp)+, a1 ! array base address
sub.l (a0), d0 ! relative index
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move.l d1,-(sp)
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move.l (8,a0), d1 ! # bytes / element
cmp.l #1, d1
bne 2f
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move.l (sp),a0
clr.l (sp)
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move.b (a1,d0.l), (3,sp) ! one byte element
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jmp (a0)
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2:
cmp.l #2, d1
bne 4f
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move.l (sp),a0
clr.l (sp)
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move.w (a1,d0.l*2), (2,sp) ! two byte element
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jmp (a0)
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4:
muls.l d1, d0
add.l d0, a1 ! address of 4n byte element
add.l d1, a1 ! because of predecrement
asr.l #2, d1
sub.l #1, d1
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move.l (sp)+,a0
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1:
move.l -(a1), -(sp)
dbf d1, 1b
jmp (a0)
.align 2