X86 INSTRUCTIONS::: DATA TRANSFER INSTRUCTIONS:::5-MOVE STRING

Move byte Syntax : movsb The movsb instruction copies one byte from the memory location specified in esi to the location specified in edi. If the direction flag is cleared, then esi and edi are incremented after the operation. Otherwise, if the direction flag is set, then the pointers are decremented. In that case the copy would happen in the reverse direction, starting at the highest address and moving toward lower addresses until ecx is zero. Operands None. Modified flags No FLAGS are modified by this instruction Example : section .text ; copy mystr into mystr2 mov esi, mystr ; loads address of mystr into esi mov edi, mystr2 ; loads address of mystr2 into edi cld ; clear direction flag (forward) mov ecx,6 rep movsb ; copy six times section .bss mystr2: resb 6 section .data mystr db "Hello", 0x0 Move Word Syntax : movsw The movsw instruction copies one word (two bytes) from the location specified in esi to the location specified in edi. It basically does the same thing as movsb, except with words instead of bytes. Operands None. Modified flags No FLAGS are modified by this instruction Example : section .code ; copy mystr into mystr2 mov esi, mystr mov edi, mystr2 cld mov ecx,4 rep movsw ; mystr2 is now AaBbCca\0 section .bss mystr2: resb 8 section .data mystr db "AaBbCca", 0x0