With symbols assembler

src/main.rs

@@ -1,39 +1,141 @@
+use std::cell::RefCell;
+use std::collections::HashMap;
 use std::env;
 use std::ffi;
 use std::fs;
 use std::io::Write;
 use std::path;
-use std::process;
+use std::path::PathBuf;
 
 use regex::Regex;
+use types::Address;
 use types::Instruction;
 
 mod code;
 mod parser;
 mod types;
 
-fn process(instruction: String) -> String {
-    match parser::parse(&instruction) {
-        Instruction::AInstruction(parsed_instruction) => {
-            match parsed_instruction.decimal.parse::<i32>() {
-                Ok(decimal) => {
-                    let translated = code::decimal_to_fifteen_bits_binary(&decimal);
+fn remove_whitespace_and_comments(content: String) -> String {
+    let re = Regex::new(r"\s*\/\/.*").unwrap();
+    
+    content
+        .lines()
+        .map(|line| line.trim())
+        .filter(|line| !line.starts_with("//") && !line.is_empty())
+        .map(|line| re.replace_all(line, ""))
+        .map(|line| format!("{}\n", line))
+        .collect::<String>()
+}
 
-                    String::from(format!("0{}", translated))
-                }
-                Err(_) => panic!("Failed to parse A instruction {}", instruction),
+fn first_pass(content: String, table: &RefCell<HashMap<String, (i32, Address)>>) -> String {
+    let mut mutable_table = table.borrow_mut();
+
+    content
+        .lines()
+        .enumerate()
+        .filter(|(_, line)| line.starts_with('(') && line.ends_with(')'))
+        .collect::<Vec<(usize, &str)>>()
+        .iter()
+        .enumerate()
+        .for_each(|(index, (line_number, instruction))| {
+            let symbol = instruction[1..instruction.len() - 1].to_string();
+
+            if index > 0 {
+                mutable_table.insert(symbol, ((*line_number - index) as i32, Address::ROM));
+            } else {
+                mutable_table.insert(symbol, (*line_number as i32, Address::ROM));
             }
-        }
-        Instruction::CInstruction(parsed_instruction) => {
-            String::from("111")
-                + code::translate_comp(&parsed_instruction.comp.unwrap_or_else(|| "".to_string()))
-                    .as_str()
-                + code::translate_dest(&parsed_instruction.dest.unwrap_or_else(|| "".to_string()))
-                    .as_str()
-                + code::translate_jump(&parsed_instruction.jump.unwrap_or_else(|| "".to_string()))
-                    .as_str()
-        }
-    }
+        });
+
+    content
+        .lines()
+        .filter(|line| !line.starts_with('(') && !line.ends_with(')'))
+        .map(|line| format!("{}\n", line))
+        .collect()
+}
+
+fn second_pass(content: String, table: &RefCell<HashMap<String, (i32, Address)>>) -> String {
+    content
+        .lines()
+        .map(|instruction| {
+            let mut mutable_table = table.borrow_mut();
+
+            if instruction.is_empty() {
+                return instruction.to_string();
+            }
+
+            match parser::parse(&instruction.to_string(), &mut mutable_table) {
+                Instruction::AInstruction(parsed_instruction) => {
+                    match parsed_instruction.decimal.parse::<i32>() {
+                        Ok(decimal) => {
+                            let translated = code::decimal_to_fifteen_bits_binary(&decimal);
+
+                            String::from(format!("0{}", translated))
+                        }
+                        Err(_) => panic!("Failed to parse A instruction {}", instruction),
+                    }
+                }
+                Instruction::CInstruction(parsed_instruction) => {
+                    String::from("111")
+                        + code::translate_comp(
+                            &parsed_instruction.comp.unwrap_or_else(|| "".to_string()),
+                        )
+                        .as_str()
+                        + code::translate_dest(
+                            &parsed_instruction.dest.unwrap_or_else(|| "".to_string()),
+                        )
+                        .as_str()
+                        + code::translate_jump(
+                            &parsed_instruction.jump.unwrap_or_else(|| "".to_string()),
+                        )
+                        .as_str()
+                }
+            }
+        })
+        .filter(|line| !line.is_empty())
+        .map(|line| format!("{}\n", line))
+        .collect::<String>()
+}
+
+fn process(path: &PathBuf) {
+    let filepath = path
+        .canonicalize()
+        .unwrap()
+        .to_str()
+        .unwrap()
+        .replace("asm", "hack");
+    let mut file = fs::File::create(filepath).unwrap();
+    let content = fs::read_to_string(&path).expect("You must provide a correct filepath!");
+    let symbol_table = RefCell::new(HashMap::from([
+        (String::from("SP"), (0, Address::ROM)),
+        (String::from("LCL"), (1, Address::ROM)),
+        (String::from("ARG"), (2, Address::ROM)),
+        (String::from("THIS"), (3, Address::ROM)),
+        (String::from("THAT"), (4, Address::ROM)),
+        (String::from("R0"), (0, Address::RAM)),
+        (String::from("R1"), (1, Address::RAM)),
+        (String::from("R2"), (2, Address::RAM)),
+        (String::from("R3"), (3, Address::RAM)),
+        (String::from("R4"), (4, Address::RAM)),
+        (String::from("R5"), (5, Address::RAM)),
+        (String::from("R6"), (6, Address::RAM)),
+        (String::from("R7"), (7, Address::RAM)),
+        (String::from("R8"), (8, Address::RAM)),
+        (String::from("R9"), (9, Address::RAM)),
+        (String::from("R10"), (10, Address::RAM)),
+        (String::from("R11"), (11, Address::RAM)),
+        (String::from("R12"), (12, Address::RAM)),
+        (String::from("R13"), (13, Address::RAM)),
+        (String::from("R14"), (14, Address::RAM)),
+        (String::from("R15"), (15, Address::RAM)),
+        (String::from("SCREEN"), (16384, Address::RAM)),
+        (String::from("KBD"), (24576, Address::RAM)),
+    ]));
+    let without_whitespace_and_comments = remove_whitespace_and_comments(content);
+    let ran_through_first_pass = first_pass(without_whitespace_and_comments, &symbol_table);
+    let ran_through_second_pass = second_pass(ran_through_first_pass, &symbol_table);
+
+    file.write_all(ran_through_second_pass.as_bytes()).unwrap();
 }
 
 fn main() {
@@ -48,24 +150,7 @@ fn main() {
         .to_str()
         .unwrap_or("")
     {
-        "asm" => {
-            let filepath = path.canonicalize().unwrap().to_str().unwrap().replace("asm", "hack");
-            let mut file = fs::File::create(filepath).unwrap();
-            let content = fs::read_to_string(&path).expect("You must provide a correct filepath!");
-            let re = Regex::new(r"\s*\/\/.*").unwrap();
-            let processed: String = content
-                .lines()
-                .filter(|line| !line.starts_with("//") && !line.is_empty())
-                .map(|line| re.replace_all(line, ""))
-                .map(|line| process(line.to_string()))
-                .map(|line| format!("{}\n", line))
-                .collect();
-
-            file.write_all(processed.as_bytes()).unwrap();
-        }
-        _ => {
-            println!("The file extension must be asm!");
-            process::exit(1)
-        }
+        "asm" => process(&path),
+        _ => panic!("The file extension must be asm!"),
     }
 }

src/parser.rs

@@ -1,15 +1,42 @@
-use crate::types::{AInstruction, CInstruction, Instruction};
+use std::collections::HashMap;
+
+use crate::types::{AInstruction, Address, CInstruction, Instruction};
 use regex::Regex;
 
-pub fn parse(instruction: &String) -> Instruction {
+pub fn parse(instruction: &String, table: &mut HashMap<String, (i32, Address)>) -> Instruction {
     let mut cloned = instruction.clone();
 
     if cloned.starts_with('@') {
         cloned.remove(0);
 
-        return Instruction::AInstruction(AInstruction {
-            decimal: cloned.trim().to_string(),
-        });
+        if cloned.parse::<i32>().is_ok() {
+            return Instruction::AInstruction(AInstruction { decimal: cloned });
+        } else {
+            if table.contains_key(&cloned) {
+                return Instruction::AInstruction(AInstruction {
+                    decimal: table.get(&cloned).copied().unwrap().0.to_string(),
+                });
+            } else {
+                let mut temp_table = table.clone();
+
+                temp_table.remove_entry(&String::from("SCREEN"));
+                temp_table.remove_entry(&String::from("KBD"));
+
+                let address = temp_table
+                    .iter()
+                    .filter(|(_, (_, address))| matches!(address, Address::RAM))
+                    .fold(
+                        0,
+                        |acc, (_, (addr, _))| if *addr > acc { *addr } else { acc },
+                    )
+                    + 1;
+
+                table.insert(cloned, (address, Address::RAM));
+                return Instruction::AInstruction(AInstruction {
+                    decimal: address.to_string(),
+                });
+            }
+        }
     } else {
         let re_dest = Regex::new(r"=").unwrap();
         let re_jump = Regex::new(r";").unwrap();

src/types.rs

@@ -8,6 +8,12 @@ pub struct CInstruction {
     pub jump: Option<String>,
 }
 
+ #[derive(Clone, Copy)]
+pub enum Address {
+    RAM,
+    ROM
+}
+
 pub enum Instruction {
     AInstruction(AInstruction),
     CInstruction(CInstruction),