Question

This is a mips assembly code for a C code.I am simulating it using Qtspim, but I am getting an error as titled above.

    .text

# j=$s0 , i=$t0 

main:
        li $s0,5 # setting j to 5 
        li $t0,0 # setting i to zero


loop:
        slti $t1,$t0,8
        bne $t1,1,Exit
        add $s0,$s0,$t0
        addi $t0,$t0,1
        beq $s0,10,Exit
        j loop


Exit:       

The C code which I am trying to convert into assembly is as below

  j=5;

for(t=0,i<8;i++){

    j=j+1;
    if(j==10)
        return;
}

Answer 1

The assembly code seems ok. I guess your problem is that you have delayed branching enabled in QtSpim.
This means that the instruction that follows a branch is always executed, regardless of the action taken by the branch.

The easy fix is either to disable delayed branching, or to add a NOP after any branch instruction.

In your code:

.text
main:
        li $s0,5 # setting j to 5 
        li $t0,0 # setting i to zero


loop:
        slti $t1,$t0,8
        bne $t1,1,Exit
        nop             # added a nop to prevent the addition when branch is taken
        add $s0,$s0,$t0
        addi $t0,$t0,1
        beq $s0,10,Exit
        j loop
        nop             # added a nop to prevent executing unknown data after the unconditional jump
Exit:   
        j Exit          # code added so we don't drop off executing after this point
        nop