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EtchedPixels / Fuzix-Compiler-Kit

Fuzix C Compiler Project
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support6800/__switchl.s doesn't return correct results #99

Closed zu2 closed 2 weeks ago

zu2 commented 2 weeks ago

Use AccB as loop counter.

    .export __switchl

__switchl:
    ; X holds the switch table, hireg:D the value
    ; Juggle as we are short of regs here - TODO find a nicer approach
    staa @tmp
    stab @tmp+1
    ldab 1,x
    inx
    inx
    tstb
    beq gotit
next:
    ldaa ,x
    cmpa @hireg
    bne nomat
    ldaa 1,x
    cmpa @hireg+1
    bne nomat
    ldaa 2,x
    cmpa @tmp
    bne nomat
    ldaa 3,x
    cmpa @tmp+1
    bne nomat
    ldx 4,x
    jmp ,x
nomat:
    inx
    inx
    inx
    inx
    inx
    inx
moveon:
    decb            ; We know < 256 entries per switch
    bne next
gotit:
    ldx ,x
    jmp ,x