.section .boot_text, "ax", @progbits
.code64

.global _entry64
_entry64:
    mov $global_descriptor_table_data, %rax
    mov %rax, %ss
    mov %rax, %ds
    mov %rax, %es
    mov %rax, %fs
    mov %rax, %gs

    call invoke_global_constructors
    
    xor %rax, %rax
    mov %rax, %rbp
    mov %rax, %rdx
    mov %rax, %rsi

    mov $stack_size, %rcx
    shr $3, %rcx
    lea (stack_bottom), %rdi
    rep stosq

    mov %rax, %rdi

    call main

1:
    hlt
    jmp 1b