I am trying an array to save i * j values and print the values from array.
I have two loops loop1, loop2, where loop1 takes i and loop2 takes on j. I am trying to save the i * j in a myarray which is space datatype.
I am getting exception Memory address out of bounds and unable to find whats the error.
.data
myarray: .space 10000
n: .word 1
space_line: .asciiz " "
new_line: .asciiz "\n"
.text
.globl main
main:
lw $a0, n
la $a1, myarray
li $a2, -1 #row
li $t0, 0
li $t2, 0
loop1:
addi $a2, $a2,1
bge $a2, $a0, print_loop
li $a3, 0 #column
j loop2
loop2:
bge $a3, $a0, loop1
#multiply a2 and a3
mul $t1, $a2, $a3
sw $t1, 0($a1)
addu $a1, $a1,4
addi $a3, $a3,1
j loop2
print_loop:
mul $t3, $a0, $a0
bge $t0, $t3, exit
li $v0, 4
lw $a0, myarray($t2)
syscall
li $v0, 4
lw $a0, space_line
syscall
rem $t4, $t3, $a0
beqz $t4, newline
addu $t2, $t2, 4
addi $t0, $t0, 1
j print_loop
newline:
li $v0, 4
lw $a0, myarray($t2)
syscall
exit:
# Done, terminate program.
li $v0, 10
syscall # all done!
.end main
For n =4,i am expecting the output in console as
0 0 0 0
0 1 2 3
0 2 4 6
0 4 8 12
You can find this problem by single stepping in the debugger. Start with the smallest possible input, like n=1 as you're showing. After each instruction, verify that it did what you want, and that it didn't do anything else except what you wanted.
Here's a hint: Pay attention to the difference between la and lw. Also, If you want to put syscalls in the middle of your code or loops, then avoid the $a0 and $v0 registers for your own variables — just makes things easier/better.