cc65/libsrc/runtime/regswap.s

29 lines
625 B
ArmAsm

;
; Ullrich von Bassewitz, 25.11.2002
;
; CC65 runtime: Swap x bytes of register variable space
;
.export regswap
.importzp sp, regbank, tmp1
.proc regswap
sta tmp1 ; Store count
@L1: lda regbank,x ; Get old value
pha ; Save it
lda (sp),y ; Get stack loc
sta regbank,x ; Store new value
pla
sta (sp),y ; Store old value
inx
iny
dec tmp1
bne @L1
rts
.endproc