how can i convert my swap function from C to mips32 code?

Question

Ihave this function:

void swap(int i, int j){
int temp=v[i];
v[i]=v[j];
v[j]=temp;
}

where i and j are elements from a global array v[]

I have written this code in mips thus far but the array stays the same and nothing changes:

swap:                           # swap entry point
sll $t3,$a0,2                   
sll $t4,$a1,2                  
add $t3,$gp,$t3                
add $t4,$gp,$t4
lw $t0,0($t3)                    #t0=v[i]
lw $t1,0($t4)                    #t1=v[j]  
sw $t0,0($t4)
sw $t1,0($t3)
        jr      $ra             # return to caller

where $a0=i and $a0=j

Thanks in advance