# bedir t karaabalı
        # 2025
        # collatz problem

.text
# void collatz_len_and_peek(uint64_t x, uint64_t *steps, uint64_t *peek)
.global collatz_len_and_peek
collatz_len_and_peek:
    # Collatz problem implementation
    # x -> rdi, steps -> rsi, peak -> rdx

    movq $0, (%rsi) # *steps=0
    movq %rdi, (%rdx) # *peak = x
    movq %rdi, %r8 # r8(n) (caller-saved) = x
    
.loop:
    cmpq $1, %r8 # while (n != 1)
    je .done
    testq $1, %r8 # 1 and n
    jz .even
    # odd case
    leaq (%r8, %r8, 2), %r8 # n *= 3 -> lea base + index * scale
    addq $1,%r8 # n += 1
    jmp .next_step
.even:
    shrq $1, %r8 # n /= 2
.next_step:
    cmpq (%rdx), %r8 # if (n > *peek) n - *peek
    jle .next
    movq %r8, (%rdx) # *peek = n
.next:
    addq $1, (%rsi) # (*steps)++
    jmp .loop
.done:
    ret