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https://github.com/fadden/6502bench.git
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Added a compiled C implementation of strlen(). The most interesting part about this is that it references a 16-bit value via direct-page address $ff, which means you'd want a local variable with address=$ff and width=2. The current UI prevents this.
247 lines
5.8 KiB
ArmAsm
247 lines
5.8 KiB
ArmAsm
; Copyright 2019 faddenSoft. All Rights Reserved.
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; See the LICENSE.txt file for distribution terms (Apache 2.0).
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;
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; Assembler: Merlin 32
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; 65816 version
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org $1000
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; Define these as project symbols.
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PROJ_ZERO equ $00
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PROJ_ONE equ $01
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CONST_ZERO equ $f0
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CONST_ONE equ $f1
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PTR_2 equ $f8 ;used to test uniqifier later on
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ldy PROJ_ZERO
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lda (PROJ_ONE),y
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sta $03 ;undefined yet
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ldx $04 ;undefined yet
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lda CONST_ZERO,S ;explicitly set symbol
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sta CONST_ONE,S ;leave as default (hex)
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; TABLE - test redefinition of project symbol values
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]VAR_ZERO equ $00 ;2b
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]VAR_TWO equ $02 ;1b
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]VAR_THREE equ $03 ;1b
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]CONST_ZERO equ $f0 ;1b const
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ldy PROJ_ZERO ;should become ]VAR_ZERO
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lda (PROJ_ONE),y ;should become ]VAR_ZERO+1
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sta $03 ;should become ]VAR_THREE
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ldx $04 ;undefined yet
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lda CONST_ZERO,S ;should become ]CONST_ZERO
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sta CONST_ONE,S ;leave as default (hex)
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eor $00 ;explicitly format as decimal
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ora $f0,S ;explicitly format as decimal
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; TABLE - test redefinition of symbol labels
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]PROJ_ZERO equ $10 ;EDIT: rename to PROJ_ZERO
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]DPCODE equ $80 ;EDIT: rename to DPCODE
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lda $00
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lda $01
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lda $02
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lda $03
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lda $04
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lda $10
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lda $11
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lda $80
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; TABLE/CLEAR - empty table
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ldx $00
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ldx $01
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ldx $02
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; confirm that hidden tables are skipped over
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dfb $2c
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; TABLE (hidden)
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]HIDDEN0 equ $00
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]HIDDEN1 equ $01
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lda #$ff
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ldy $00
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ldy $01
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ldy $02
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dfb $2c
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; TABLE (not hidden)
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]NH0 equ $00
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]NH1 equ $01
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:label lda #$fe
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beq :label
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ldy $00
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ldy $01
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ldy $02
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nop
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; TABLE
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]PTR0 equ $10 ;2b
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]CONST0 equ $10 ;4b
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lda ]PTR0
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ldx ]PTR0+1
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ldy ]PTR0+2 ;should be hex
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lda (]CONST0,S),y
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sta (]CONST0+3,S),y
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; test redefinition of name
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; TABLE
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]PTR equ $20 ;2b
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ldx ]PTR
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; TABLE
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]PTR equ $22 ;2b
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ldx ]PTR
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; TABLE
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]PTR equ $24 ;2b
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ldx ]PTR
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; define user label to try to trip up the uniqifier
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PTR_1 nop
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; test redefinition of value
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; TABLE/CLEAR
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]PTR_A equ $20 ;2b
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ldy ]PTR_A ;PTR_A
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]PTR_B equ $1f ;2b
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ldy ]PTR_A ;PTR_B+1
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]PTR_C equ $1d ;4b
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ldy ]PTR_A ;PTR_C+3
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]PTR_D equ $21 ;1b
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ldy ]PTR_A ;should come up as hex
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; TABLE
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]VAL0 equ $30 ;1b
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]VAL1 equ $31 ;1b
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]VAL2 equ $32 ;1b
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]VAL3 equ $33 ;1b
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]VAL4 equ $34 ;1b
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]VAL5 equ $35 ;1b
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and ]VAL0
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and ]VAL1
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and ]VAL2
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and ]VAL3
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and ]VAL4
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and ]VAL5
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; TABLE
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]VAL14 equ $31 ;4b
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and ]VAL0
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and ]VAL1 ;these four become ]VAL14
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and ]VAL2
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and ]VAL3
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and ]VAL4
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and ]VAL5
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; TABLE - test direct page label vs. variable
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]DPNOP equ $80
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lda ]DPNOP
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jsr DPCODE
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rts
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org $0080
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DPCODE nop
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lda DPCODE ;should be DPNOP
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lda |DPCODE ;should be DPCODE
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lda >DPCODE ;should be DPCODE
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; Local label test. ca65 v2.18 erases cheap local label scope when it
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; encounters a constant or .set.
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LOCAL1 lda #$2c ;EDIT: format as ASCII
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ldx $1234 ;put variable table here with one arbitrary entry
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beq LOCAL1
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LOCAL2 lda $2c ;EDIT: format as ASCII
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ldx $5678 ;put empty variable table here
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beq LOCAL2
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; Test C-style call frame (issue #96).
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nop
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clc
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xce
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rep #$30
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pea ^STRING
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pea STRING
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jsl STRLEN
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sec
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xce
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jmp AFTER_STRLEN
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STRING asc 'testing',00
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; C sample, for something like:
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; int strlen(const char* arg) {
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; len = 0;
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; while (*arg++ != '\0')
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; len++;
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; return len;
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; }
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;
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; Assume SP at $2000 before call. On entry:
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; $2000 string-$00
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; $1fff string-bank
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; $1ffe string-hi
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; $1ffd string-lo
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; $1ffc ret-bank
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; $1ffb ret-hi
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; $1ffa ret-lo
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; S=$1ff9
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;
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; After call frame set up:
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; $1ff9 saved-D-hi
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; $1ff8 saved-D-lo
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; S=$1ff7 before SBC/ADC
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; $1ff7 (ptr-$00)
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; $1ff6 (ptr-bank)
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; $1ff5 (ptr-hi)
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; $1ff4 (ptr-lo)
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; $1ff3 (len-hi)
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; $1ff2 (len-lo)
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;
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; D=$1f00
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; S=$1ff1
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;
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]LEN equ $f2 ;2 bytes
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]PTR equ $f4 ;4 bytes
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]ARG equ $fd ;4 bytes; spans [$fd,$100]
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mx %00
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STRLEN phd
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tsc
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sec
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sbc #$00f7
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tcd
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adc #$00f0 ;note carry set
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tcs
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stz ]LEN
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:Loop ldx ]ARG+2
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lda ]ARG
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inc ]ARG
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bne :NoInc
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inc ]ARG+2
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:NoInc sta ]PTR
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stx ]PTR+2
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lda []PTR]
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and #$00ff
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beq :Ret
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inc ]LEN
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bra :Loop
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:Ret lda ]LEN
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tay
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tdc
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clc
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adc #$00f7
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tcs
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tya
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pld
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rtl
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AFTER_STRLEN
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bit $ff
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bit: $00ff
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bit $0100
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rts
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