Added if statements, and made Expr::Return work.

This commit is contained in:
Goren Barak 2023-11-24 09:56:49 -05:00
parent 325ae07f1c
commit 2f942d3371
2 changed files with 48 additions and 15 deletions

View file

@ -7,12 +7,19 @@ macro_rules! fasm_codegen {
fasm_codegen(&$exprs, true)
};
(function: $exprs:expr) => {
(fun: $exprs:expr) => {
fasm_codegen($exprs, false)
}
}
pub fn temp(counter: u64) -> String {
format!("tmp{:?}", counter)
}
pub fn fasm_codegen(exprs: &Vec<Expr>, not_a_function: bool) -> String {
// A counter for how many temporary variables have been created. This is used to create new ones. The new ones will be called tmp1, tmp2, etc.
let mut tmp_counter: u64 = 0;
// Define asm_func, used for functions.
let mut asm_func = String::new();
// Define asm_data, used for variables.
@ -140,13 +147,16 @@ pub fn fasm_codegen(exprs: &Vec<Expr>, not_a_function: bool) -> String {
Expr::Breakpoint => {
// Write the interrupt for a debugger breakpoint.
asm_start.push_str("\tint3\n");
asm_start.push_str("\txor rax, rax\n");
},
// Return something from a function.
Expr::Return(e) => {
// Do the operation that should later be returned.
asm_start.push_str(fasm_codegen!(fun: &e));
// Move the return value to rbp + 8.
asm_start.push_str(format!("mov [rbp + 8], {}", e.unwrap()).as_str());
// [rbp + 8] ← return_value
asm_start.push_str("mov [rbp + 8], rax");
// 8(%rbp) ← return_value
},
// A function defenition.
@ -154,18 +164,44 @@ pub fn fasm_codegen(exprs: &Vec<Expr>, not_a_function: bool) -> String {
// In x86-64 assembly, a function is defined as <function_name>:. Push this to the `asm_func`.
asm_func.push_str(format!("{}:\n", e.name).as_str());
// Call the function itself specifying that you are defining a function, and push the returned value to `asm_func`.
asm_func.push_str(fasm_codegen!(function: &e.contents).as_str());
asm_func.push_str(fasm_codegen!(fun: &e.contents).as_str());
// Use the ret instruction to return from the procedure.
asm_func.push_str("\tret\n");
},
Expr::If(e) => {
// Increment the temporary variable/function counter.
tmp_counter += 1;
// Compare the left and right value.
asm_start.push_str(format!("\tcmp {}, {}\n", e.left.unwrap(), e.right.unwrap()).as_str());
// Check what the condition is.
match e.cond {
COND_OP::EQ => {
// If the compared values are equal to each other jump to the temporary function.
asm_start.push_str(format!("je .{}", temp(tmp_counter)).as_str());
},
COND_OP::NE => {
// If the compared values are not equal to eachother jump to the temporary function.
asm_start.push_str(format!("jne .{}", temp(tmp_counter)).as_str());
}
}
// Create the temporary function.
asm_func.push_str(format!(".{}:\n", temp(tmp_counter)).as_str());
asm_func.push_str(fasm_codegen!(fun: &e.action).as_str());
asm_func.push_str("\tret\n");
}
_ => unsafe {
// Write some data I randomly typed to your memory because don't going around playing with something that I haven't implemented yet.
let mut ptr = 0x00 as *mut f64;
::std::ptr::write(ptr, 124010240120401240.12410240124120401240);
},
}
}

View file

@ -1,11 +1,13 @@
use std::rc::Rc;
#[derive(Debug)]
pub enum Expr<'a> {
MathExpr(Math<'a>),
FunCall(FunCall<'a>),
FunDefinition(FunDefinition<'a>),
VarDefinition(VarDefinition<'a>),
Return(Value<'a>),
If(IfStatement<'a>),
Return(Vec<Expr<'a>>),
If(IfCondition<'a>),
Breakpoint
}
@ -79,16 +81,11 @@ pub enum Value<'a> {
}
#[derive(Debug)]
pub struct IfStatement<'a> {
pub condition: Condition<'a>,
pub if_true: Vec<Expr<'a>>,
}
#[derive(Debug)]
pub struct Condition<'a> {
pub struct IfCondition<'a> {
pub left: Value<'a>,
pub right: Value<'a>,
pub between: COND_OP,
pub cond: COND_OP,
pub action: Vec<Expr<'a>>
}
#[derive(Debug)]