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61 lines
1.4 KiB
ArmAsm
61 lines
1.4 KiB
ArmAsm
;
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; Ullrich von Bassewitz, 11.06.1998
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;
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; char* strpbrk (const char* s1, const char* s2);
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;
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.export _strpbrk
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.import popax, return0
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.importzp ptr1, ptr2, tmp1, tmp2, tmp3
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_strpbrk:
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jsr popax ; get s2
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sta ptr2
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stx ptr2+1
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jsr popax ; get s1
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sta ptr1
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stx ptr1+1
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ldy #$00
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L1: lda (ptr1),y ; get next char from s1
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beq L9 ; jump if done
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sta tmp2 ; save char
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iny
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bne L2
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inc ptr1+1
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L2: sty tmp3 ; save index into s1
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ldy #0 ; get index into s2
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L3: lda (ptr2),y ;
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beq L4 ; jump if done
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cmp tmp2
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beq L6
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iny
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bne L3
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; The character was not found in s2. Increment the counter and start over
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L4: ldy tmp3 ; reload index
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inx
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bne L1
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inc tmp1
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bne L1
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; A character was found. Calculate a pointer to this char in s1 and return it.
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L6: ldx ptr1+1
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lda tmp3 ; get y offset
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clc
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adc ptr1
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bcc L7
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inx
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L7: rts
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; None of the characters in s2 was found - return NULL
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L9: jmp return0
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