.global _add
.type _add, @function

.text

_add:
    push %rbp
    mov %rsp, %rbp
    push %rax
    push %rbx
    push %rcx
    mov 0x10(%rbp), %rax    # lhs
    mov 0x18(%rbp), %rbx  # rhs
    xor %rcx, %rcx              # i = 0
    clc
    pushf
loop:
    popf
    movl (%rax, %rcx, 4), %esi  # rhs[i]
    movl (%rbx, %rcx, 4), %edi  # lhs[i]
    adc %esi, %edi
    movl %edi, (%rbx, %rcx, 4)
    inc %rcx
    pushf
    cmp %rcx, %rdx          # i != block_count
    jnz loop
    popf
    pop %rcx
    pop %rbx
    pop %rax
    pop %rbp
    ret