bfin/src/asm_gen.rs

91 lines
2.2 KiB
Rust

use std::collections::VecDeque;
use crate::tokenizer::{Token, TokenType};
pub fn generate(tokens: Vec<Token>) -> String {
let mut output = String::new();
// reserving mem
output.push_str(
"section .bss\n\
data: resb 65536\n",
);
// global start label
output.push_str(
"global _start\n\
section .text\n\
_start:\n",
);
// create the pointer for our data
output.push_str("mov rdx, data\n");
let mut loops = 0;
let mut stack: VecDeque<usize> = VecDeque::new();
for token in tokens {
match token.r#type {
TokenType::Plus(x) => {
output.push_str(&format!("add byte[rdx], {x}\n"));
}
TokenType::Minus(x) => {
output.push_str(&format!("sub byte[rdx], {x}\n"));
}
TokenType::MoveRight(x) => {
output.push_str(&format!("add rdx, {x}\n"));
}
TokenType::MoveLeft(x) => {
output.push_str(&format!("sub rdx, {x}\n"));
}
TokenType::Output => {
output.push_str(
"push rdx\n\
mov rax, 1\n\
mov rdi, 1\n\
mov rsi, rdx\n\
mov rdx, 1\n\
syscall\n\
pop rdx\n",
);
}
TokenType::Input => {
output.push_str(
"push rdx\n\
mov rax, 0\n\
mov rdi, 0\n\
mov rsi, rdx\n\
mov rdx, 1\n\
syscall\n\
pop rdx\n",
);
}
TokenType::BracketOpen => {
output.push_str(&format!(
".loop_{loops}_start:\n\
cmp byte[rdx], 0\n\
je .loop_{loops}_end\n"
));
stack.push_back(loops);
loops += 1;
}
TokenType::BracketClose => {
let current_loop = stack.pop_back().unwrap();
output.push_str(&format!(
"cmp byte[rdx], 0\n\
jne .loop_{current_loop}_start\n\
.loop_{current_loop}_end:\n",
));
}
}
}
// exit syscall
output.push_str(
"mov rax, 60\n\
mov rdi, 0\n\
syscall\n",
);
output
}