From b79cd46b4b8acc2dfee0cb73eef96b1353de1544 Mon Sep 17 00:00:00 2001
From: Toni <antpiasecki@gmail.com>
Date: Wed, 11 Mar 2026 14:46:44 +0100
Subject: [PATCH] malloc structs and allow using them as types

---
 src/analyzer.rs       | 14 +++++++++++++-
 src/codegen_x86_64.rs | 26 +++++++++++++++++++++++++-
 src/parser.rs         | 15 ---------------
 3 files changed, 38 insertions(+), 17 deletions(-)

diff --git a/src/analyzer.rs b/src/analyzer.rs
index 44f5020..c4d3d93 100644
--- a/src/analyzer.rs
+++ b/src/analyzer.rs
@@ -8,6 +8,7 @@ use crate::{
 pub struct Analyzer {
     pub functions: HashMap<String, i32>,
     pub constants: HashMap<String, u64>,
+    pub structs: HashMap<String, HashMap<String, usize>>,
 }
 
 impl Analyzer {
@@ -15,6 +16,7 @@ impl Analyzer {
         Analyzer {
             functions: HashMap::new(),
             constants: HashMap::new(),
+            structs: HashMap::new(),
         }
     }
 
@@ -117,7 +119,17 @@ impl Analyzer {
                 }
                 self.functions.insert(name.lexeme.clone(), -1);
             }
-            Stmt::Struct { name: _, fields: _ } => todo!(),
+            Stmt::Struct { name, fields } => {
+                let mut fields_map: HashMap<String, usize> = HashMap::new();
+
+                let mut offset: usize = 0;
+                for field in fields {
+                    fields_map.insert(field.var_name.lexeme.clone(), offset);
+                    offset += 8;
+                }
+
+                self.structs.insert(name.lexeme.clone(), fields_map);
+            }
         }
         Ok(())
     }
diff --git a/src/codegen_x86_64.rs b/src/codegen_x86_64.rs
index dcd54ab..beab783 100644
--- a/src/codegen_x86_64.rs
+++ b/src/codegen_x86_64.rs
@@ -69,6 +69,9 @@ macro_rules! emit {
 
 static REGISTERS: [&str; 6] = ["rdi", "rsi", "rdx", "rcx", "r8", "r9"];
 
+// TODO: currently they are all just 64 bit values
+static BUILTIN_TYPES: [&str; 7] = ["void", "u8", "i64", "str", "bool", "ptr", "array"];
+
 pub struct CodegenX86_64<'a> {
     output: String,
     data_section: String,
@@ -170,6 +173,10 @@ _builtin_environ:
                     },
                 };
 
+                if !self.is_valid_type_name(&var_type) {
+                    return error!(&name.loc, "unrecognized type: ".to_owned() + &var_type);
+                }
+
                 self.compile_expr(env, initializer)?;
                 let offset = env.define_var(name.lexeme.clone(), var_type);
                 emit!(&mut self.output, "    mov QWORD [rbp-{}], rax", offset);
@@ -627,8 +634,25 @@ _builtin_environ:
                     return error!(&op.loc, "can only take address of variables and functions");
                 }
             },
-            Expr::New(_) => todo!(),
+            Expr::New(struct_name) => {
+                let struct_fields = &self.analyzer.structs[&struct_name.lexeme];
+
+                let memory_size = struct_fields.len() * 8;
+
+                emit!(&mut self.output, "    mov rdi, {}", memory_size);
+                emit!(&mut self.output, "    call malloc");
+            }
         }
         Ok(())
     }
+
+    fn is_valid_type_name(&self, name: &str) -> bool {
+        if BUILTIN_TYPES.contains(&name) {
+            return true;
+        }
+        if self.analyzer.structs.contains_key(name) {
+            return true;
+        }
+        false
+    }
 }
diff --git a/src/parser.rs b/src/parser.rs
index b25849b..9452e04 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -91,9 +91,6 @@ pub enum Expr {
     New(Token),
 }
 
-// TODO: currently they are all just 64 bit values
-static TYPES: [&str; 7] = ["void", "u8", "i64", "str", "bool", "ptr", "array"];
-
 pub struct Parser {
     tokens: Vec<Token>,
     current: usize,
@@ -159,9 +156,6 @@ impl Parser {
                 self.consume(TokenType::Colon, "expected ':' after parameter name")?;
 
                 let var_type = self.consume(TokenType::Identifier, "expected parameter type")?;
-                if !TYPES.contains(&var_type.lexeme.as_str()) {
-                    return error!(&name.loc, format!("unknown type: {}", var_type.lexeme));
-                }
 
                 params.push(Param { var_type, var_name });
                 if !self.match_token(&[TokenType::Comma]) {
@@ -173,9 +167,6 @@ impl Parser {
         self.consume(TokenType::RightBracket, "expected ']' after arguments")?;
         self.consume(TokenType::Colon, "expected ':' after '['")?;
         let return_type = self.consume(TokenType::Identifier, "expected return type")?;
-        if !TYPES.contains(&return_type.lexeme.as_str()) {
-            return error!(&name.loc, format!("unknown type: {}", return_type.lexeme));
-        }
 
         self.is_inside_function = true;
         let body = Box::new(self.block()?);
@@ -201,9 +192,6 @@ impl Parser {
             self.consume(TokenType::Colon, "expected ':' after field name")?;
 
             let var_type = self.consume(TokenType::Identifier, "expected field type")?;
-            if !TYPES.contains(&var_type.lexeme.as_str()) {
-                return error!(&name.loc, format!("unknown type: {}", var_type.lexeme));
-            }
 
             fields.push(Param { var_type, var_name });
         }
@@ -218,9 +206,6 @@ impl Parser {
 
         let var_type = if self.match_token(&[TokenType::Colon]) {
             let token = self.consume(TokenType::Identifier, "expected variable type")?;
-            if !TYPES.contains(&token.lexeme.as_str()) {
-                return error!(&name.loc, format!("unknown type: {}", token.lexeme));
-            }
             Some(token)
         } else {
             None