WebThe CMPSB (W) instruction can be used to compare a byte (word) in one string (DS:offset in SI) with a byte (word) in another string (ES:offset in DI). The comparison is executed by … WebLODS/LODSB/LODSW. This instruction copies a byte (word) of string from the location pointed to by SI. The SI value is automatically incremented (depending on the DF value) after each movement by 1 byte (2 bytes) for a byte string (word string). This instruction is preferred over MOV for string manipulation due to its treatment of the SI pointer ...

X86-assembly/Instructions/rep - aldeid

WebIn STOSB instruction SI is decremented or incremented by 4 1 2 3 Question No: 3 ( M - 1 ) . CMPS instruction subtracts the source location to the destination location. Destination … WebThe LODS, LODSB, LODSW, and LODSD instructions can be preceded by the REP prefix for block loads of ECX bytes, words, or doublewords. More often, however, these instructions … raymond marshall el paso tx

CS 271 final Flashcards Quizlet

WebThe STOS, STOSB, STOSW, and STOSD instructions can be preceded by the REP prefix for block loads of ECX bytes, words, or doublewords. More often, however, these instructions are used within a LOOP construct because data needs to be moved into the AL, AX, or EAX register before it can be stored. Web13 Jul 2024 · [EBP + 0Ch] appears to be a CHAR(size = 1 byte) since it is loaded into AL register which is then implicitly used by stosb instruction with rep prefix as the byte value … Web# After the LODS instruction is used to place a string value in the # EAX register, the STOS instruction can be used to place it # in another memory location. # - STOSB: Stores a byte of data from the AL register # - STOSW: Stores a word (2 bytes) of data from the AX register # - STOSL: Stores a doubleword (4 bytes) of data from the EAX register simplified new call ui