42 lines
579 B
Plaintext
42 lines
579 B
Plaintext
;Compares strings from SI and DI until a null and either sets the carry flag if they are equal or clears it if not.
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cmpstr:
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;Store the initial registers in the stack
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push ax
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push bx
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;Compare the strings
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.loop:
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;Load the current characters
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mov al, [si]
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mov bl, [di]
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;Compare the characters
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cmp al, bl
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;Check for difference
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jne .neq
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;Check for the string end
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cmp al, 0x0
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je .eq
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;Repeat for the next characters
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inc si
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inc di
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jmp .loop
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;Set the carry flag
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.eq:
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stc
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jmp .done
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;Clear the carry flag
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.neq:
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clc
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.done:
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;Load the initial registers from the stack
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pop bx
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pop ax
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ret
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