mirror of
https://github.com/cc65/cc65.git
synced 2024-12-24 11:31:31 +00:00
37 lines
464 B
ArmAsm
37 lines
464 B
ArmAsm
;
|
|
; Ullrich von Bassewitz, 08.10.1998
|
|
;
|
|
; CC65 runtime: -= operator for longs on the stack
|
|
;
|
|
|
|
.export lsubeq0sp, lsubeqysp
|
|
.importzp sp, sreg
|
|
|
|
lsubeq0sp:
|
|
ldy #0
|
|
lsubeqysp:
|
|
sec
|
|
eor #$FF
|
|
adc (sp),y
|
|
sta (sp),y
|
|
pha ; Save low byte
|
|
iny
|
|
txa
|
|
eor #$FF
|
|
adc (sp),y
|
|
sta (sp),y
|
|
tax
|
|
iny
|
|
lda (sp),y
|
|
sbc sreg
|
|
sta (sp),y
|
|
sta sreg
|
|
iny
|
|
lda (sp),y
|
|
sbc sreg+1
|
|
sta (sp),y
|
|
sta sreg+1
|
|
pla
|
|
rts
|
|
|