Assembly Language Reference (Native x64)

PBXB64 includes a native x64 assembler that accepts Intel-syntax assembly and produces COFF objects or PE executables directly. No external assemblers required.

Supported Extensions

.asm and .s files are automatically routed through the native x64 assembler pipeline.

Basic Structure

section .text
global main

main:
    push rbp
    mov rbp, rsp
    mov eax, 42
    pop rbp
    ret

Assembler Pipeline

.asm / .s  ->  ASM Lexer  ->  ASM Parser  ->  Encoder  ->  COFF Object  ->  PE Linker

Data Sections & Variables

section .data
msg: db "Hello, World!", 0
len: equ $ - msg

section .bss
buffer: resb 1024

section .text
global main
main:
    lea rcx, [rel msg]
    call printf
    ret

Integration with Other Frontends

Assembly files can be linked seamlessly with B64, BASIC, and C object files using the PE linker:

PBXB64 main.b64 helper.asm -o program.exe
PBXB64 prog.c utils.s -o mixed.exe

Syntax Notes

• Intel syntax: instruction destination, source
• Registers: rax, rbx, rcx, rdx, rsi, rdi, rsp, rbp, r8-r15
• Modes: 64-bit (default), 32-bit (rax -> eax, etc.)
• Immediate values: decimal (42), hex (0x2A), octal (0o52)