CODEWITHSUNDEEP
assemblymips
lazybumnumba1
lazybumnumba1

Reputation: 1

trying to copy a .asciiz string to allocated .space in MIPS

im trying to make a simple program that copies a string soplas to a .space directive called buffer. im getting errors but im not sure where im going wrong, the beq statement would be comparing the byte to the 0 ascii character since thats how strings are null terminated, right? copy is called using jal, hence the jr $ra in the done subroutine

copy:   
     lb   $t1, soplas($t0) 
     nop
     sb   $t1, buffer($t0)
     nop
     addi $t0, $t0,1
     beq  $t1, 0x00, done
     j copy
     nop
     nop
    
    
done: 
    jr $ra
    nop
    nop

Upvotes: 0

Views: 89

Answers (1)

Erik Eidt
Erik Eidt

Reputation: 26666

Let's say your C code would look like this:

void copy() {
    int i = 0; // start i at 0 to work with soplas[0]/buffer[0]
    while (true) {
        char ch = soplas[i];
        buffer[i] = ch;
        i++;
        if (ch == '\0') break;
    }
}

Can you see which line of the C code you're missing in the assembly version?

Also, if you're using MIPS with branch delay slots, even beq and bne need nops, not just j and jr.

Upvotes: 0

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