MIPS Assembly Code Snippets Analysis

The following sections present corrected and formatted MIPS assembly code snippets, illustrating common programming tasks such as finding the minimum of two array elements and finding the maximum value in an array.

Snippet 1: Calculating Minimum of Two Array Elements (v[i] = min(A[i], B[i]))

This section translates the high-level concept v[i] = min(A[i], B[i]) within a loop where i goes from 0 to n-1.

MIPS Implementation for Minimum Calculation

# Initialization (assuming s3=i, s4=n, s0=base_A, s1=base_B, s2=base_V)
    move $s3, $zero      # i = 0
loop:
    sll $t0, $s3, 2      # t0 = i * 4 (byte offset)
    add $t1, $s0, $t0    # t1 = address of A[i]
    add $t2, $s1, $t0    # t2 = address of B[i]
    add $t3, $s2, $t0    # t3 = address of V[i]

    lw $a0, 0($t1)       # a0 = A[i]
    lw $a1, 0($t2)       # a1 = B[i]
    jal min              # Call min function

    sw $v0, 0($t3)       # V[i] = result (returned in v0)

    addi $s3, $s3, 1     # i++
    slt $t4, $s3, $s4    # t4 = (i < n)
    bne $t4, $zero, loop # Branch back if i < n

# Function: min(a0, a1) -> returns minimum in $v0
min:
    slt $t5, $a0, $a1    # t5 = 1 if a0 < a1, else 0
    beq $t5, $zero, else # If a0 >= a1, go to else
    move $v0, $a0        # v0 = a0 (a0 is smaller)
    jr $ra
else:
    move $v0, $a1        # v0 = a1 (a1 is smaller or equal)
    jr $ra

Snippet 2: Finding Maximum Value in an Array (max = A[i] if A[i] > max)

This section implements finding the maximum value in an array, iterating from index 0 up to 29 (or n-1 if s2 holds n).

MIPS Implementation for Maximum Finding

# Initialization (assuming s1=base_A, s2=n, s0=max, s3=i)
    move $s0, $zero      # Initialize max to 0 (or load A[0] if max=A[0] is desired)
    move $s3, $zero      # i = 0

    # If max = A[0] initialization is required:
    # lw $s0, 0($s1)     # max = A[0]
    # addi $s3, $zero, 1 # Start loop from i=1

loop:
    sll $t0, $s3, 2      # t0 = i * 4
    add $t1, $s1, $t0    # t1 = address of A[i]
    lw $t2, 0($t1)       # t2 = A[i]

    # Check if A[i] > max
    sgt $t3, $s0, $t2    # t3 = 1 if s0 > t2 (max > A[i]), else 0
    bne $t3, $zero, next # If max > A[i], skip update

    move $s0, $t2        # max = A[i]

next:
    addi $s3, $s3, 1     # i++
    slti $t4, $s3, 30    # t4 = (i < 30)
    bne $t4, $zero, loop # Branch back if i < 30

    # Result is in $s0 (max)

Snippet 3: Array Copy Operation (v[i] = v[j]; j--)

This snippet appears to be part of a reverse copy or manipulation, where v[i] is assigned the value from v[j], and j is decremented in each step of a loop controlled by i.

MIPS Implementation for Array Copy (Conceptual)

# Initialization (assuming s0=base_V, s1=base_V, t1=i_counter, t0=j_index)
    move $t1, $zero      # i = 0
    addi $t1, $zero, 29  # If i counts down from 29
    move $t0, $zero      # j = 0 (or some starting index)

loop:
    sll $t2, $t1, 2      # t2 = i * 4 (offset for v[i])
    sll $t3, $t0, 2      # t3 = j * 4 (offset for v[j])

    add $t4, $s1, $t3    # t4 = address of v[j]
    lw $t6, 0($t4)       # t6 = v[j]

    add $t5, $s0, $t2    # t5 = address of v[i]
    sw $t6, 0($t5)       # v[i] = v[j]

    sub $t0, $t0, 1      # j--
    addi $t1, $t1, 1     # i++ (If i is the loop counter controlling the iteration count)

    # Loop termination condition is missing/unclear based on original structure
    # Example termination if i goes from 0 to 29:
    # slti $t3, $t1, 30
    # bne $t3, $zero, loop