MIPS mult, multu and mul instructions

This is sample MIPS assembler code demonstrating the correct operation of the mult, multu and mul instructions by EzMIPS, the MIPS assembler editor & simulator. The code is fully commented.

Launch EzMIPS, copy the following MIPS code and paste it into EzMIPS. Assemble, Run.

# -------------- mult, multu, mul multiplication ----------------- #

.data

szMenu:         .ascii  "Choose multiplication type\n"
                .ascii  "--------------------------\n"
                .ascii  "1. Use mult instruction\n"
                .ascii  "2. Use multu instruction\n"
                .ascii  "3. Use mul instruction\n"
                .asciiz "4. Exit\n"

.text

main:

# ................................................................ #
# Comment any 2 lines for $t5 and any 2 lines for $t6 and check result of
# mult, multu and mul. Any combination should give appropriate results!

    li $t5, 0xffffffff
    li $t5, 0x7fffffff
    li $t5, 0x80000000

    li $t6, 0xffffffff
    li $t6, 0x7fffffff
    li $t6, 0x80000000

# ................................................................ #
    
    li $t1, 1
    li $t2, 2
    li $t3, 3
    li $t4, 4

# ................................................................ #

print_menu:

    # print menu
    li $v0, 4
    la $a0, szMenu
    syscall

# ................................................................ #
    
    # get user input
    li $v0, 5
    syscall
    # $v0 holds user input

    beq $v0, $t4, exit
    beq $v0, $t3, use_mul
    beq $v0, $t2, use_multu
    bne $v0, $t1, print_menu

# ................................................................ #

use_mult:
    mult $t5, $t6
    j print_menu         # Display menu again

# ................................................................ #

use_multu:
    multu $t5, $t6
    j print_menu         # Display menu again

# ................................................................ #

use_mul:
    mul $t0, $t5, $t6
    j print_menu         # Display menu again

# ................................................................ #

exit:

    li $v0, 10
    syscall

# ---------------------------------------------------------------- #

Please let me know of any suggestions or bugs regarding the code above.

Regards,

Antonis