mirror of
https://github.com/cc65/cc65.git
synced 2024-10-30 12:28:25 +00:00
77 lines
1.3 KiB
ArmAsm
77 lines
1.3 KiB
ArmAsm
|
;
|
||
|
|
; Ullrich von Bassewitz, 13.08.1998
|
||
|
|
;
|
||
|
|
; CC65 runtime: helper stuff for mod/div/mul with long signed ints
|
||
|
|
;
|
||
|
|
|
||
|
|
; When negating values, we will ignore the possibility here, that one of the
|
||
|
|
; values if $80000000, in which case the negate will fail.
|
||
|
|
|
||
|
|
.export poplsargs, adjlsres
|
||
|
|
.import getlop, negeax
|
||
|
|
.importzp sreg, tmp1, ptr1, ptr3, ptr4
|
||
|
|
|
||
|
|
poplsargs:
|
||
|
|
jsr getlop ; Get the operands
|
||
|
|
|
||
|
|
; Calculate the sign of the result, that is sign(op1) * sign(op2) and
|
||
|
|
; remember it.
|
||
|
|
|
||
|
|
lda sreg+1
|
||
|
|
eor ptr4+1
|
||
|
|
sta tmp1 ; Save it across call
|
||
|
|
|
||
|
|
; Make both operands positive
|
||
|
|
|
||
|
|
lda sreg+1 ; Is the operand negative?
|
||
|
|
bpl L1 ; Jump if not
|
||
|
|
|
||
|
|
clc ; Make it positive
|
||
|
|
lda ptr1
|
||
|
|
eor #$FF
|
||
|
|
adc #$01
|
||
|
|
sta ptr1
|
||
|
|
lda ptr1+1
|
||
|
|
eor #$FF
|
||
|
|
adc #$00
|
||
|
|
sta ptr1+1
|
||
|
|
lda sreg
|
||
|
|
eor #$FF
|
||
|
|
adc #$00
|
||
|
|
sta sreg
|
||
|
|
lda sreg+1
|
||
|
|
eor #$FF
|
||
|
|
adc #$00
|
||
|
|
sta sreg+1
|
||
|
|
|
||
|
|
L1: lda ptr4+1 ; Is the operand nagative?
|
||
|
|
bpl L2 ; Jump if not
|
||
|
|
|
||
|
|
clc ; Make it positive
|
||
|
|
lda ptr3
|
||
|
|
eor #$FF
|
||
|
|
adc #$01
|
||
|
|
sta ptr3
|
||
|
|
lda ptr3+1
|
||
|
|
eor #$FF
|
||
|
|
adc #$00
|
||
|
|
sta ptr3+1
|
||
|
|
lda ptr4
|
||
|
|
eor #$FF
|
||
|
|
adc #$00
|
||
|
|
sta ptr4
|
||
|
|
lda ptr4+1
|
||
|
|
eor #$FF
|
||
|
|
adc #$00
|
||
|
|
sta ptr4+1
|
||
|
|
|
||
|
|
L2: rts
|
||
|
|
|
||
|
|
; Adjust the result of a mod/div/mul operation
|
||
|
|
|
||
|
|
adjlsres:
|
||
|
|
ldy tmp1 ; Check if we must adjust the sign
|
||
|
|
bpl L2
|
||
|
|
jmp negeax ; Netage value
|
||
|
|
|