luallaby 0.1.0

**Work in progress** A pure-Rust Lua interpreter/compiler
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46

use std::rc::Rc;

use crate::ast::Chunk;
use crate::compiler::{Compiler, ScopeType};
use crate::error::Result;
use crate::vm::{FuncObject, Literal, OpCode};

impl Compiler {
    pub(super) fn compile_chunk(&mut self, chunk: Chunk) -> Result<FuncObject> {
        self.scope_enter(ScopeType::Func);
        self.code_push();

        if !self.compile_block(chunk.block)? {
            let ret_reg = self.scopes.reg_reserve();
            self.code.emit(
                OpCode::Lit {
                    val: Literal::Empty,
                    dst_reg: ret_reg,
                },
                self.code.get_pos_last(),
            );
            // Ensure that function has at least one return
            self.code
                .emit(OpCode::Return { ret_reg }, self.code.get_pos_last());
            self.scopes.reg_free(ret_reg);
        }

        let scope = self
            .scope_leave(ScopeType::Func, self.code.get_pos_last())?
            .unwrap();
        let code = self.code_pop();
        assert!(scope.locals.is_empty());
        assert!(scope.ups.len() == 1);
        assert!(self.code_stack.is_empty());
        Ok(FuncObject {
            regs: scope.regs.count(),
            locals_cap: scope.locals_cap,
            params: Vec::new(),
            ups: scope.ups.into_iter().map(|up| up.upper).collect(),
            varargs: true,
            code: Rc::new(code),
            linedefined: 0,
            lastlinedefined: 0,
        })
    }
}