has string_table now :^)

src/ast.rs

@@ -1,5 +1,9 @@
 use std::num::NonZero;
 
+use itertools::Itertools;
+
+use crate::string_table::{self, ImmOrIndex};
+
 pub type Node = NonZero<u32>;
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -40,16 +44,20 @@ pub enum Tag {
         body: Node,
     },
     Ident {
-        name: String,
+        name: string_table::Index,
     },
     IntegralConstant {
-        bits: u64,
-        ty: IntegralType,
+        bits: string_table::Index,
+        ty: Option<IntegralType>,
     },
     FloatingConstant {
         bits: u64,
         ty: FloatingType,
     },
+    Constant {
+        bytes: ImmOrIndex,
+        ty: Type,
+    },
     Block {
         /// ReturnStmt | ExprStmt | VarDecl
         statements: Vec<Node>,
@@ -231,11 +239,12 @@ impl IntegralType {
     }
 }
 
-#[derive(Debug, Clone, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Eq, Hash)]
 pub enum Type {
     Any,
     Void,
     Bool,
+    ComptimeNumber,
     Integer(IntegralType),
     Floating(FloatingType),
     Pointer {
@@ -248,7 +257,86 @@ pub enum Type {
     },
 }
 
+impl core::fmt::Display for Type {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Type::Any => f.write_str("?"),
+            Type::Void => f.write_str("void"),
+            Type::Bool => f.write_str("bool"),
+            Type::ComptimeNumber => f.write_str("comptime_number"),
+            Type::Integer(t) => t.fmt(f),
+            Type::Floating(t) => t.fmt(f),
+            Type::Pointer { constness, pointee } => {
+                write!(f, "*{}{}", if *constness { "const " } else { "" }, pointee)
+            }
+            Type::Fn {
+                parameter_types,
+                return_type,
+            } => {
+                write!(f, "fn (")?;
+                for param in parameter_types.iter().map(|p| Some(p)).intersperse(None) {
+                    match param {
+                        Some(param) => param.fmt(f)?,
+                        None => write!(f, ", ")?,
+                    }
+                }
+
+                write!(f, ") -> {}", return_type)
+            }
+        }
+    }
+}
+
+impl PartialEq for Type {
+    fn eq(&self, other: &Self) -> bool {
+        match (self, other) {
+            (Self::ComptimeNumber, Self::Integer(_)) => true,
+            (Self::Integer(_), Self::ComptimeNumber) => true,
+            (Self::ComptimeNumber, Self::Floating(_)) => true,
+            (Self::Floating(_), Self::ComptimeNumber) => true,
+            (Self::Integer(l0), Self::Integer(r0)) => l0 == r0,
+            (Self::Floating(l0), Self::Floating(r0)) => l0 == r0,
+            (
+                Self::Pointer {
+                    constness: l_constness,
+                    pointee: l_pointee,
+                },
+                Self::Pointer {
+                    constness: r_constness,
+                    pointee: r_pointee,
+                },
+            ) => l_constness == r_constness && l_pointee == r_pointee,
+            (
+                Self::Fn {
+                    parameter_types: l_parameter_types,
+                    return_type: l_return_type,
+                },
+                Self::Fn {
+                    parameter_types: r_parameter_types,
+                    return_type: r_return_type,
+                },
+            ) => l_parameter_types == r_parameter_types && l_return_type == r_return_type,
+            _ => core::mem::discriminant(self) == core::mem::discriminant(other),
+        }
+    }
+}
+
 impl Type {
+    pub fn equal_type(&self, rhs: &Self) -> Option<Type> {
+        match (self, rhs) {
+            (Self::ComptimeNumber, Self::Floating(_))
+            | (Self::ComptimeNumber, Self::Integer(_)) => Some(rhs.clone()),
+            (Self::Integer(_), Self::ComptimeNumber)
+            | (Self::Floating(_), Self::ComptimeNumber) => Some(self.clone()),
+            _ => {
+                if self.eq(rhs) {
+                    Some(self.clone())
+                } else {
+                    None
+                }
+            }
+        }
+    }
     pub fn void() -> Type {
         Self::Void
     }
@@ -256,7 +344,7 @@ impl Type {
         Self::Void
     }
     pub fn any() -> Type {
-        Self::Void
+        Self::Any
     }
     pub fn into_ptr(self) -> Type {
         Self::Pointer {
@@ -274,52 +362,67 @@ impl Type {
 
     pub fn can_negate(&self) -> bool {
         match self {
-            Type::Bool | Type::Integer(_) => true,
+            Type::ComptimeNumber | Type::Bool | Type::Integer(_) => true,
             _ => false,
         }
     }
 
     pub fn can_bitxor_and_or(&self) -> bool {
         match self {
-            Type::Bool | Type::Integer(_) => true,
+            Type::ComptimeNumber | Type::Bool | Type::Integer(_) => true,
             _ => false,
         }
     }
 
     pub fn can_add_sub(&self) -> bool {
         match self {
-            Type::Pointer { .. } | Type::Floating(_) | Type::Integer(_) => true,
+            Type::ComptimeNumber | Type::Pointer { .. } | Type::Floating(_) | Type::Integer(_) => {
+                true
+            }
             _ => false,
         }
     }
     pub fn can_shift(&self) -> bool {
         match self {
-            Type::Integer(_) => true,
+            Type::ComptimeNumber | Type::Integer(_) => true,
             _ => false,
         }
     }
     pub fn can_eq(&self) -> bool {
         match self {
-            Type::Pointer { .. } | Type::Bool | Type::Floating(_) | Type::Integer(_) => true,
+            Type::ComptimeNumber
+            | Type::Pointer { .. }
+            | Type::Bool
+            | Type::Floating(_)
+            | Type::Integer(_) => true,
             _ => false,
         }
     }
     pub fn can_cmp(&self) -> bool {
         match self {
-            Type::Pointer { .. } | Type::Floating(_) | Type::Integer(_) => true,
+            Type::ComptimeNumber | Type::Pointer { .. } | Type::Floating(_) | Type::Integer(_) => {
+                true
+            }
             _ => false,
         }
     }
     pub fn can_mul_div_rem(&self) -> bool {
         match self {
-            Type::Floating(_) | Type::Integer(_) => true,
+            Type::ComptimeNumber | Type::Floating(_) | Type::Integer(_) => true,
             _ => false,
         }
     }
 
     pub fn is_integer(&self) -> bool {
         match self {
-            Type::Integer(_) => true,
+            Type::ComptimeNumber | Type::Integer(_) => true,
+            _ => false,
+        }
+    }
+
+    pub fn is_float(&self) -> bool {
+        match self {
+            Type::ComptimeNumber | Type::Floating(_) => true,
             _ => false,
         }
     }
@@ -336,6 +439,7 @@ impl Type {
         match self {
             Type::Any => 0,
             Type::Void => 0,
+            Type::ComptimeNumber => 0,
             Type::Bool => 1,
             Type::Integer(t) => t.bits.div_ceil(8) as u32,
             Type::Floating(t) => match t {
@@ -351,7 +455,7 @@ impl Type {
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum PrimitiveType {
     FloatingType(FloatingType),
-    IntegralType(Node),
+    IntegralType(IntegralType),
     Bool,
     Void,
 }

src/lexer.rs

@@ -582,6 +582,250 @@ fn try_parse_integral_type(source: &mut Chars) -> Result<Option<()>> {
     Ok(Some(()))
 }
 
+pub mod bigint {
+
+    use super::Radix;
+    pub struct BigInt(Vec<u32>);
+
+    impl BigInt {
+        pub fn parse_digits<C: IntoIterator<Item = char>>(text: C, radix: Radix) -> BigInt {
+            parse_bigint(text.into_iter(), radix)
+        }
+
+        pub fn bit_width(&self) -> u32 {
+            let mut bits = self.0.len() as u32;
+
+            for d in self.0.iter().rev() {
+                if *d == 0 {
+                    bits -= u32::BITS;
+                } else {
+                    bits -= d.leading_zeros();
+                    break;
+                }
+            }
+
+            bits
+        }
+
+        pub fn from_bytes_le(bytes: &[u8]) -> BigInt {
+            let data = bytes
+                .chunks(4)
+                .map(|chunk| {
+                    let mut int = [0u8; 4];
+                    int[..chunk.len()].copy_from_slice(chunk);
+                    u32::from_le_bytes(int)
+                })
+                .collect::<Vec<_>>();
+
+            BigInt(data)
+        }
+
+        pub fn into_bytes_le(&self) -> Vec<u8> {
+            let mut bytes = Vec::<u8>::new();
+
+            for d in &self.0[..] {
+                bytes.extend(&d.to_le_bytes());
+            }
+
+            let count = bytes.iter().rev().take_while(|&&b| b == 0).count();
+            bytes.truncate(bytes.len() - count);
+
+            bytes
+        }
+    }
+
+    impl core::ops::Add for BigInt {
+        type Output = Self;
+
+        fn add(mut self, mut rhs: Self) -> Self::Output {
+            let (mut digits, carry) = if self.0.len() > rhs.0.len() {
+                let c = add_bigint(&mut self.0, &rhs.0);
+                (self.0, c)
+            } else {
+                let c = add_bigint(&mut rhs.0, &self.0);
+                (rhs.0, c)
+            };
+
+            if carry {
+                digits.push(u32::from(carry));
+            }
+
+            BigInt(digits)
+        }
+    }
+
+    impl core::ops::Sub for BigInt {
+        type Output = Self;
+
+        fn sub(mut self, rhs: Self) -> Self::Output {
+            if self.0.len() < rhs.0.len() {
+                println!("extending self by {} zeroes", rhs.0.len() - self.0.len());
+                self.0
+                    .extend(core::iter::repeat(0).take(rhs.0.len() - self.0.len()));
+                println!("self: {self:?}");
+            }
+            sub_bigint(&mut self.0, &rhs.0);
+
+            self
+        }
+    }
+
+    impl core::fmt::Debug for BigInt {
+        fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+            let mut list = f.debug_list();
+            list.entries(self.0.iter()).finish()
+        }
+    }
+
+    #[allow(unused)]
+    /// lhs must be bigger than rhs
+    fn sub_bigint(lhs: &mut [u32], rhs: &[u32]) {
+        let len = lhs.len().min(rhs.len());
+        let (l_lo, l_hi) = lhs.split_at_mut(len);
+        let (r_lo, r_hi) = rhs.split_at(len);
+
+        println!("lhs: {{ lo: {l_lo:?}, hi: {l_hi:?} }}");
+        println!("rhs: {{ lo: {r_lo:?}, hi: {r_hi:?} }}");
+
+        let mut borrow = false;
+        for (lhs, rhs) in l_lo.iter_mut().zip(r_lo) {
+            (*lhs, borrow) = lhs.borrowing_sub(*rhs, borrow);
+        }
+
+        if borrow {
+            for lhs in l_hi {
+                (*lhs, borrow) = lhs.borrowing_sub(0, borrow);
+            }
+        }
+
+        if borrow || !r_hi.iter().all(|&v| v == 0) {
+            panic!("sub failed: borrow: {borrow}");
+        }
+    }
+
+    /// lhs must be bigger than rhs
+    fn add_bigint(lhs: &mut [u32], rhs: &[u32]) -> bool {
+        let (l_lo, l_hi) = lhs.split_at_mut(rhs.len());
+
+        let mut carry = false;
+        for (lhs, rhs) in l_lo.iter_mut().zip(rhs) {
+            (*lhs, carry) = lhs.carrying_add(*rhs, carry);
+        }
+
+        if carry {
+            for d in l_hi.iter_mut() {
+                (*d, carry) = d.carrying_add(0, carry);
+                if !carry {
+                    break;
+                }
+            }
+        }
+
+        carry
+    }
+
+    fn parse_bigint(text: impl Iterator<Item = char>, radix: Radix) -> BigInt {
+        let digits = text
+            .filter_map(|c| match c {
+                '_' => None,
+                c => Some(radix.map_digit(c)),
+            })
+            .collect::<Vec<_>>();
+
+        let (max, power) = {
+            let radix = radix.radix() as u64;
+            let mut power = 1;
+            let mut base = radix;
+            while let Some(b) = base.checked_mul(radix) {
+                if b > u32::MAX as u64 {
+                    break;
+                }
+                base = b;
+                power += 1;
+            }
+            (base, power)
+        };
+        let radix = radix.radix() as u32;
+
+        let r = digits.len() % power;
+        let i = if r == 0 { power } else { r };
+        let (head, tail) = digits.split_at(i);
+
+        let first = head
+            .iter()
+            .fold(0, |acc, &digit| acc * radix + digit as u32);
+        let mut data = vec![first];
+
+        for chunk in tail.chunks(power) {
+            if data.last() != Some(&0) {
+                data.push(0);
+            }
+            let mut carry = 0u64;
+            for digit in data.iter_mut() {
+                carry += *digit as u64 * max as u64;
+                *digit = carry as u32;
+                carry >>= u32::BITS;
+            }
+            assert!(carry == 0);
+            let next = chunk
+                .iter()
+                .fold(0, |acc, &digit| acc * radix + digit as u32);
+
+            let (res, mut carry) = data[0].carrying_add(next, false);
+            data[0] = res;
+            if carry {
+                for digit in data[1..].iter_mut() {
+                    (*digit, carry) = digit.carrying_add(0, carry);
+                    if !carry {
+                        break;
+                    }
+                }
+            }
+        }
+        BigInt(data)
+    }
+
+    #[cfg(test)]
+    mod tests {
+        use super::*;
+
+        #[test]
+        fn parse() {
+            let bigint = super::parse_bigint("2_cafe_babe_dead_beef".chars(), Radix::Hex);
+            println!("{:#x?}", bigint);
+            let bigint = super::parse_bigint("f".chars(), Radix::Hex);
+            println!("{:#x?}", bigint);
+        }
+        #[test]
+        fn add() {
+            let a = super::parse_bigint("2_0000_0000_0000_0000".chars(), Radix::Hex);
+            println!("{:#x?}", a);
+            let b = super::parse_bigint("cafebabe".chars(), Radix::Hex);
+            println!("{:#x?}", b);
+            let sum = a + b;
+            println!("{:#x?}", sum);
+        }
+        #[test]
+        fn sub() {
+            let a = super::parse_bigint("2_0000_0000_0000_0000".chars(), Radix::Hex);
+            println!("{:#x?}", a);
+            let b = super::parse_bigint("ffff_ffff".chars(), Radix::Hex);
+            println!("{:#x?}", b);
+            let sum = a - b;
+            println!("{:#x?}", sum);
+        }
+        #[test]
+        fn overflowing_sub() {
+            let a = super::parse_bigint("2_0000_0000_0000_0000".chars(), Radix::Hex);
+            println!("{:#x?}", a);
+            let b = super::parse_bigint("ffff_ffff".chars(), Radix::Hex);
+            println!("{:#x?}", b);
+            let sum = b - a;
+            println!("{:#x?}", sum);
+        }
+    }
+}
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub enum Radix {
     Hex,
@@ -638,6 +882,28 @@ impl Radix {
             _ => None,
         }
     }
+    pub fn map_digit(self, c: char) -> u8 {
+        match self {
+            Radix::Hex => match c {
+                '0'..='9' => c as u8 - b'0',
+                'a'..='f' => 10 + c as u8 - b'a',
+                'A'..='F' => 10 + c as u8 - b'A',
+                _ => unreachable!(),
+            },
+            Radix::Bin => match c {
+                '0'..='1' => c as u8 - b'0',
+                _ => unreachable!(),
+            },
+            Radix::Dec => match c {
+                '0'..='9' => c as u8 - b'0',
+                _ => unreachable!(),
+            },
+            Radix::Oct => match c {
+                '0'..='7' => c as u8 - b'0',
+                _ => unreachable!(),
+            },
+        }
+    }
     pub fn folding_method(self) -> fn(u64, char) -> u64 {
         match self {
             Radix::Hex => {

src/lib.rs

@@ -1,4 +1,10 @@
-#![feature(extract_if, iter_advance_by, box_into_inner, hash_extract_if)]
+#![feature(
+    extract_if,
+    iter_advance_by,
+    box_into_inner,
+    hash_extract_if,
+    bigint_helper_methods
+)]
 #![allow(unused_macros)]
 
 pub mod ast;

src/parser.rs

@@ -5,7 +5,8 @@ use itertools::Itertools;
 use crate::{
     ast::{FloatingType, IntegralType, LetOrVar, Node, PrimitiveType, Tag, Type},
     common::NextIf,
-    lexer::{Radix, TokenIterator},
+    lexer::{bigint::BigInt, Radix, TokenIterator},
+    string_table::{Index, StringTable},
     symbol_table::{SymbolKind, SymbolTable},
     tokens::Token,
 };
@@ -47,12 +48,6 @@ impl Nodes {
             inner: vec![Tag::Root],
         }
     }
-    pub fn get_ident_str(&self, node: Node) -> Option<&str> {
-        match &self.inner[node.get() as usize] {
-            Tag::Ident { name } => Some(name.as_str()),
-            _ => None,
-        }
-    }
     fn len(&self) -> u32 {
         self.inner.len() as u32
     }
@@ -87,6 +82,7 @@ impl Nodes {
 pub struct Tree {
     pub nodes: Nodes,
     pub st: SymbolTable,
+    pub strings: StringTable,
     pub global_decls: Vec<Node>,
 }
 
@@ -125,6 +121,7 @@ impl Tree {
         Self {
             nodes: Nodes::new(),
             st: SymbolTable::new(),
+            strings: StringTable::new(),
             global_decls: Vec::new(),
         }
     }
@@ -205,22 +202,25 @@ impl Tree {
         IntegralType { signed, bits }
     }
 
-    fn parse_integral_constant(token: Token, lexeme: &str) -> (u64, IntegralType) {
+    fn parse_integral_constant(token: Token, lexeme: &str) -> (BigInt, Option<IntegralType>) {
         let radix = Radix::from_token(token).unwrap();
 
         // TODO: figure out how to do this safely for bigger types, whether to
         // wrap, saturate, or else.
         let iter = &mut lexeme.char_indices();
-        let value = iter
+        let digits = iter
             .take_while_ref(|&(_, c)| radix.is_digit()(c) || c == '_')
             .filter(|&(_, c)| c != '_')
-            .fold(0u64, |acc, (_, c)| radix.folding_method()(acc, c));
+            .map(|(_, c)| c)
+            .collect::<Vec<_>>();
+
+        let value = crate::lexer::bigint::BigInt::parse_digits(digits, radix);
 
         let ty = match iter.clone().next() {
             Some((_, 'u')) | Some((_, 'i')) => {
-                Self::parse_integral_type(&lexeme[iter.next().unwrap().0..])
+                Some(Self::parse_integral_type(&lexeme[iter.next().unwrap().0..]))
             }
-            _ => IntegralType::u32(),
+            _ => None,
         };
 
         (value, ty)
@@ -254,10 +254,18 @@ impl Tree {
     }
 
     fn parse_ident(&mut self, tokens: &mut TokenIterator) -> Result<Node> {
-        let name = tokens.expect_token(Token::Ident)?.lexeme().to_owned();
+        let ident = tokens.expect_token(Token::Ident)?;
+        let name = self.strings.insert(ident.lexeme().as_bytes());
         Ok(self.nodes.push_tag(Tag::Ident { name }))
     }
 
+    fn ident_index(&self, node: Node) -> Index {
+        match &self.nodes[node] {
+            Tag::Ident { name } => *name,
+            _ => Index::new(0, 0),
+        }
+    }
+
     pub fn parse_primitive_type(&mut self, tokens: &mut TokenIterator) -> Result<Node> {
         let token = tokens.next().ok_or(Error::UnexpectedEndOfTokens)?;
         let prim = match token.token() {
@@ -288,9 +296,10 @@ impl Tree {
                 let token = tokens.next().unwrap();
                 match Self::try_parse_integral_type(token.lexeme())? {
                     Some(int) => Ok(self.nodes.push_tag(Tag::IntegralType(int))),
-                    None => Ok(self.nodes.push_tag(Tag::Ident {
-                        name: token.lexeme().to_owned(),
-                    })),
+                    None => {
+                        let name = self.strings.insert(token.lexeme().as_bytes());
+                        Ok(self.nodes.push_tag(Tag::Ident { name }))
+                    }
                 }
             }
             _ => self.parse_primitive_type(tokens),
@@ -317,7 +326,7 @@ impl Tree {
             None
         };
 
-        let name_str = self.nodes.get_ident_str(name).unwrap().to_owned();
+        let name_str = self.strings.get_str(self.ident_index(name)).to_owned();
         let node = {
             let node = self.nodes.reserve_node();
             self.st.insert_symbol(&name_str, node, SymbolKind::Var);
@@ -361,7 +370,7 @@ impl Tree {
             None
         };
 
-        let name_str = self.nodes.get_ident_str(name).unwrap().to_owned();
+        let name_str = self.get_ident_str(name).unwrap().to_owned();
         let node = {
             let node = match self.st.find_root_symbol(&name_str) {
                 Some(r) => r.node(),
@@ -406,7 +415,7 @@ impl Tree {
 
         let param = self.nodes.reserve_node();
         self.st.insert_symbol(
-            self.nodes.get_ident_str(name).unwrap(),
+            &self.get_ident_str(name).unwrap().to_owned(),
             param,
             SymbolKind::Var,
         );
@@ -479,13 +488,13 @@ impl Tree {
 
         let decl = match self
             .st
-            .find_orderless_symbol(self.nodes.get_ident_str(name).unwrap())
+            .find_orderless_symbol(self.get_ident_str(name).unwrap())
         {
             Some(record) => record.node(),
             None => {
                 let decl = self.nodes.reserve_node();
                 self.st
-                    .insert_orderless_symbol(self.nodes.get_ident_str(name).unwrap(), decl);
+                    .insert_orderless_symbol(&self.get_ident_str(name).unwrap().to_owned(), decl);
                 decl
             }
         };
@@ -813,7 +822,16 @@ impl Tree {
             | Token::IntegerConstant => {
                 _ = tokens.next();
                 let (bits, ty) = Self::parse_integral_constant(token.token(), token.lexeme());
-                Ok(self.nodes.push_tag(Tag::IntegralConstant { bits, ty }))
+                let index = self.strings.insert(bits.into_bytes_le());
+                let ty = match ty {
+                    Some(int) => Type::Integer(int),
+                    None => Type::ComptimeNumber,
+                };
+
+                Ok(self.nodes.push_tag(Tag::Constant {
+                    bytes: crate::string_table::ImmOrIndex::Index(index),
+                    ty,
+                }))
             }
             Token::FloatingConstant
             | Token::FloatingExpConstant
@@ -822,7 +840,10 @@ impl Tree {
                 _ = tokens.next();
                 let (bits, ty) = Self::parse_floating_constant(token.token(), token.lexeme());
 
-                Ok(self.nodes.push_tag(Tag::FloatingConstant { bits, ty }))
+                Ok(self.nodes.push_tag(Tag::Constant {
+                    bytes: crate::string_table::ImmOrIndex::U64(bits),
+                    ty: Type::Floating(ty),
+                }))
             }
             Token::OpenParens => {
                 _ = tokens.next();
@@ -869,10 +890,17 @@ impl Tree {
         self.parse_program(&mut tokens)
     }
 
+    pub fn get_ident_str(&self, node: Node) -> Option<&str> {
+        match &self.nodes[node] {
+            Tag::Ident { name } => Some(self.strings.get_str(*name)),
+            _ => None,
+        }
+    }
+
     fn get_typename_str(&self, node: Node) -> Option<String> {
         match self.nodes.get_node(node) {
             Tag::IntegralType(i) => Some(i.to_string()),
-            Tag::Ident { name } => Some(name.clone()),
+            Tag::Ident { name } => Some(self.strings.get_str(*name).to_owned()),
             Tag::Pointer { pointee } => self.get_typename_str(*pointee),
             Tag::PrimitiveType(prim) => Some(prim.to_string()),
             _ => None,
@@ -897,11 +925,7 @@ impl Tree {
                     self.render_node(writer, parameters, indent)?;
                 }
                 write_indented!(indent, writer, "%{} = function_proto: {{", node.get())?;
-                write!(
-                    writer,
-                    "name: \"{}\"",
-                    self.nodes.get_ident_str(name).unwrap()
-                )?;
+                write!(writer, "name: \"{}\"", self.get_ident_str(name).unwrap())?;
                 if let Some(parameters) = parameters {
                     write!(writer, ", parameters: %{}", parameters.get())?;
                 }
@@ -921,7 +945,7 @@ impl Tree {
                     writer,
                     "%{} = {}: {},",
                     node.get(),
-                    self.nodes.get_ident_str(name).unwrap(),
+                    self.get_ident_str(name).unwrap(),
                     self.get_typename_str(ty).unwrap()
                 )
             }
@@ -949,26 +973,12 @@ impl Tree {
                 writeln_indented!(indent, writer, "}}")
             }
             Tag::Ident { name } => {
-                writeln_indented!(indent, writer, "%{} = identifier(\"{name}\")", node.get())
-            }
-            Tag::IntegralConstant { bits, ty } => {
                 writeln_indented!(
                     indent,
                     writer,
-                    "%{} = {}({})",
+                    "%{} = identifier(\"{}\")",
                     node.get(),
-                    ty.to_string(),
-                    bits
-                )
-            }
-            Tag::FloatingConstant { bits, ty } => {
-                writeln_indented!(
-                    indent,
-                    writer,
-                    "%{} = {}({})",
-                    node.get(),
-                    ty.to_string(),
-                    bits
+                    self.strings.get_str(name)
                 )
             }
             Tag::Block {
@@ -1023,7 +1033,7 @@ impl Tree {
                             "mut"
                         }
                     },
-                    self.nodes.get_ident_str(name).unwrap()
+                    self.get_ident_str(name).unwrap()
                 )?;
                 if let Some(ty) = explicit_type {
                     write!(writer, ", ty: {}", self.get_typename_str(ty).unwrap())?;
@@ -1043,7 +1053,7 @@ impl Tree {
                     writer,
                     "%{} = global_decl(name: \"{}\"",
                     node.get(),
-                    self.nodes.get_ident_str(name).unwrap()
+                    self.get_ident_str(name).unwrap()
                 )?;
                 if let Some(ty) = explicit_type {
                     write!(writer, ", ty: {}", self.get_typename_str(ty).unwrap())?;
@@ -1349,6 +1359,20 @@ impl Tree {
                         ))
                 )
             }
+            Tag::Constant { bytes, ty } => {
+                let bytes = match bytes {
+                    crate::string_table::ImmOrIndex::U64(i) => &i.to_le_bytes()[..],
+                    crate::string_table::ImmOrIndex::U32(i) => &i.to_le_bytes()[..],
+                    crate::string_table::ImmOrIndex::Index(idx) => self.strings.get_bytes(idx),
+                };
+                writeln_indented!(
+                    indent,
+                    writer,
+                    "%{} = constant{{ ty: {}, bytes: {bytes:?}}}",
+                    node.get(),
+                    ty
+                )
+            }
             _ => unreachable!(),
         }
     }
@@ -1390,15 +1414,14 @@ impl Tree {
                 constness: false,
                 pointee: Box::new(self.type_of_node(*pointee)),
             },
+            Tag::Constant { ty, .. } => ty.clone(),
             Tag::IntegralType(t) => Type::Integer(*t),
             Tag::PrimitiveType(t) => match t {
                 PrimitiveType::FloatingType(t) => Type::Floating(*t),
-                PrimitiveType::IntegralType(t) => self.type_of_node(*t),
+                PrimitiveType::IntegralType(t) => Type::Integer(*t),
                 PrimitiveType::Bool => Type::bool(),
                 PrimitiveType::Void => Type::void(),
             },
-            Tag::IntegralConstant { ty, .. } => Type::Integer(*ty),
-            Tag::FloatingConstant { ty, .. } => Type::Floating(*ty),
             Tag::Block { trailing_expr, .. } => trailing_expr
                 .map(|n| self.type_of_node(n))
                 .unwrap_or(Type::void()),
@@ -1458,6 +1481,7 @@ impl Tree {
             Tag::Le { .. } => Type::bool(),
             Tag::Ge { .. } => Type::bool(),
             Tag::DeclRef(decl) => self.type_of_node(*decl),
+            Tag::GlobalRef(decl) => self.type_of_node(*decl),
             _ => Type::void(),
         }
     }

src/string_table.rs

@@ -1,11 +1,18 @@
 use std::{collections::BTreeMap, hash::Hasher};
 
-#[derive(Debug, Clone, Copy)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub struct Index {
     pub start: u32,
     pub end: u32,
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ImmOrIndex {
+    U64(u64),
+    U32(u32),
+    Index(Index),
+}
+
 impl Index {
     pub fn new(start: u32, end: u32) -> Self {
         Self { start, end }

src/symbol_table.rs

@@ -35,13 +35,13 @@ impl SymbolPath {
         for node in self.0.iter().skip(1).rev() {
             match tree.nodes.get_node(node.unwrap()) {
                 Tag::VarDecl { name, .. } => {
-                    _ = write!(&mut buf, "V{}::", tree.nodes.get_ident_str(*name).unwrap());
+                    _ = write!(&mut buf, "V{}::", tree.get_ident_str(*name).unwrap());
                 }
                 Tag::GlobalDecl { name, .. } => {
-                    _ = write!(&mut buf, "G{}::", tree.nodes.get_ident_str(*name).unwrap());
+                    _ = write!(&mut buf, "G{}::", tree.get_ident_str(*name).unwrap());
                 }
                 Tag::FunctionProto { name, .. } => {
-                    _ = write!(&mut buf, "F{}::", tree.nodes.get_ident_str(*name).unwrap());
+                    _ = write!(&mut buf, "F{}::", tree.get_ident_str(*name).unwrap());
                 }
                 _ => {}
             }

src/triples.rs

@@ -5,6 +5,7 @@ use std::collections::{hash_map::Entry, HashMap};
 use crate::{
     ast::{FloatingType, IntegralType, Node as AstNode, Tag, Type},
     parser::Tree,
+    string_table::{ImmOrIndex, Index as StringsIndex},
     writeln_indented,
 };
 
@@ -33,27 +34,26 @@ enum Inst {
     Negate { lhs: Node },
     ReturnValue { lhs: Node },
     Return,
+    ExplicitCast { node: Node, ty: Type },
     Alloc { size: u32, align: u32 },
     AddressOf(Node),
     Load { source: Node },
     Store { dest: Node, source: Node },
 }
 
-enum Value {
-    Int { kind: IntegralType, bits: u64 },
-    Float { kind: FloatingType, bits: u64 },
+struct Value {
+    explicit_type: Option<Type>,
+    bytes: ImmOrIndex,
 }
 
 impl core::fmt::Display for Value {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        match self {
-            Value::Int { kind, bits } => {
-                write!(f, "{kind} {}", bits)
-            }
-            Value::Float { kind, bits } => {
-                write!(f, "{kind} {{{}}}", bits)
-            }
-        }
+        write!(
+            f,
+            "{} {:?}",
+            self.explicit_type.as_ref().unwrap_or(&Type::any()),
+            self.bytes
+        )
     }
 }
 
@@ -64,6 +64,14 @@ struct IRBuilder<'tree, 'ir> {
     lookup: HashMap<AstNode, NodeOrList>,
 }
 
+impl core::ops::Index<Node> for IR {
+    type Output = Inst;
+
+    fn index(&self, index: Node) -> &Self::Output {
+        &self.nodes[index as usize]
+    }
+}
+
 impl<'tree, 'ir> IRBuilder<'tree, 'ir> {
     fn new(ir: &'ir mut IR, tree: &'tree mut Tree) -> Self {
         Self {
@@ -122,7 +130,7 @@ impl<'tree, 'ir> IRBuilder<'tree, 'ir> {
                 parameters, name, ..
             } => {
                 let label = self.ir.push(Inst::Label(
-                    self.tree.nodes.get_ident_str(*name).unwrap().to_string(),
+                    self.tree.get_ident_str(*name).unwrap().to_string(),
                 ));
                 parameters.map(|p| self.visit(p));
 
@@ -172,7 +180,7 @@ impl<'tree, 'ir> IRBuilder<'tree, 'ir> {
             Tag::GlobalDecl { name, .. } => {
                 let ty = self.tree.type_of_node(node);
                 let _label = self.ir.push(Inst::Label(
-                    self.tree.nodes.get_ident_str(*name).unwrap().to_string(),
+                    self.tree.get_ident_str(*name).unwrap().to_string(),
                 ));
                 let alloca = self.ir.push(Inst::Alloc {
                     size: ty.size_of(),
@@ -194,111 +202,131 @@ impl<'tree, 'ir> IRBuilder<'tree, 'ir> {
                 let lhs = self.visit(*lhs);
                 self.ir.push(Inst::Load { source: lhs })
             }
-            Tag::IntegralConstant { bits, ty } => self.ir.push(Inst::Constant(Value::Int {
-                kind: *ty,
-                bits: *bits,
-            })),
-            Tag::FloatingConstant { bits, ty } => self.ir.push(Inst::Constant(Value::Float {
-                kind: *ty,
-                bits: *bits,
-            })),
             Tag::Assign { lhs, rhs } => {
+                let dest = self.visit(*lhs);
+                let source = self.visit(*rhs);
+
                 self.type_check(*lhs, *rhs);
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
-                self.ir.push(Inst::Store {
-                    dest: lhs,
-                    source: rhs,
-                })
+                self.ir.push(Inst::Store { dest, source })
             }
-            Tag::Add { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            Tag::Add {
+                lhs: lhs0,
+                rhs: rhs0,
+            } => {
+                let lhs = self.visit(*lhs0);
+                let rhs = self.visit(*rhs0);
+                let ty = self.type_check(*lhs0, *rhs0);
                 if !ty.can_add_sub() {
                     eprintln!("add is not available for type {ty:?}");
                 }
-
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::Add { lhs, rhs })
             }
-            Tag::Sub { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            Tag::Sub {
+                lhs: left,
+                rhs: right,
+            } => {
+                let lhs = self.visit(*left);
+                let rhs = self.visit(*right);
+
+                let ty = self.type_check(*left, *right);
                 if !ty.can_add_sub() {
                     eprintln!("sub is not available for type {ty:?}");
                 }
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::Sub { lhs, rhs })
             }
-            Tag::Mul { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            Tag::Mul {
+                lhs: left,
+                rhs: right,
+            } => {
+                let lhs = self.visit(*left);
+                let rhs = self.visit(*right);
+
+                let ty = self.type_check(*left, *right);
                 if !ty.can_mul_div_rem() {
                     eprintln!("mul is not available for type {ty:?}");
                 }
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::Mul { lhs, rhs })
             }
-            Tag::Div { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            Tag::Div {
+                lhs: left,
+                rhs: right,
+            } => {
+                let lhs = self.visit(*left);
+                let rhs = self.visit(*right);
+
+                let ty = self.type_check(*left, *right);
                 if !ty.can_mul_div_rem() {
                     eprintln!("div is not available for type {ty:?}");
                 }
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::Div { lhs, rhs })
             }
-            Tag::Rem { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            Tag::Rem {
+                lhs: left,
+                rhs: right,
+            } => {
+                let lhs = self.visit(*left);
+                let rhs = self.visit(*right);
+
+                let ty = self.type_check(*left, *right);
                 if !ty.can_mul_div_rem() {
                     eprintln!("rem is not available for type {ty:?}");
                 }
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::Rem { lhs, rhs })
             }
-            Tag::BitAnd { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            // bitwise
+            Tag::BitAnd {
+                lhs: left,
+                rhs: right,
+            } => {
+                let lhs = self.visit(*left);
+                let rhs = self.visit(*right);
+
+                let ty = self.type_check(*left, *right);
                 if !ty.can_bitxor_and_or() {
                     eprintln!("bitand is not available for type {ty:?}");
                 }
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::BitAnd { lhs, rhs })
             }
-            Tag::BitOr { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            Tag::BitOr {
+                lhs: left,
+                rhs: right,
+            } => {
+                let lhs = self.visit(*left);
+                let rhs = self.visit(*right);
+
+                let ty = self.type_check(*left, *right);
                 if !ty.can_bitxor_and_or() {
                     eprintln!("bitor is not available for type {ty:?}");
                 }
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::BitOr { lhs, rhs })
             }
-            Tag::BitXOr { lhs, rhs } => {
-                let ty = self.type_check(*lhs, *rhs);
+            Tag::BitXOr {
+                lhs: left,
+                rhs: right,
+            } => {
+                let lhs = self.visit(*left);
+                let rhs = self.visit(*right);
+
+                let ty = self.type_check(*left, *right);
                 if !ty.can_bitxor_and_or() {
                     eprintln!("bitxor is not available for type {ty:?}");
                 }
 
-                let lhs = self.visit(*lhs);
-                let rhs = self.visit(*rhs);
                 self.ir.push(Inst::BitXOr { lhs, rhs })
             }
-            Tag::Negate { lhs } => {
-                let ty = self.tree.type_of_node(*lhs);
+            Tag::Negate { lhs: left } => {
+                let lhs = self.visit(*left);
+                let ty = self.tree.type_of_node(*left);
                 if !ty.can_negate() {
                     eprintln!("negation is not available for type {ty:?}");
                 }
-
-                let lhs = self.visit(*lhs);
                 self.ir.push(Inst::Negate { lhs })
             }
             Tag::DeclRef(decl) => match self.lookup.get_mut(decl) {
@@ -320,6 +348,18 @@ impl<'tree, 'ir> IRBuilder<'tree, 'ir> {
                 let lhs = self.visit(*lhs);
                 self.ir.push(Inst::AddressOf(lhs))
             }
+            Tag::Constant { bytes, ty } => {
+                let bytes = match ty {
+                    Type::ComptimeNumber | Type::Floating(_) | Type::Integer(_) => Value {
+                        explicit_type: Some(ty.clone()),
+                        bytes: *bytes,
+                    },
+                    _ => {
+                        unimplemented!()
+                    }
+                };
+                self.ir.push(Inst::Constant(bytes))
+            }
             _ => {
                 dbg!(&self.tree.nodes[node]);
                 todo!()
@@ -327,13 +367,35 @@ impl<'tree, 'ir> IRBuilder<'tree, 'ir> {
         }
     }
 
-    fn type_check(&self, lhs: AstNode, rhs: AstNode) -> Type {
-        let t_lhs = self.tree.type_of_node(lhs);
-        let t_rhs = self.tree.type_of_node(rhs);
-        if t_lhs != t_rhs {
-            eprintln!("incompatible types {t_lhs:?} and {t_rhs:?}!");
+    fn type_check(&mut self, lhs: AstNode, rhs: AstNode) -> Type {
+        let left_t = match self.type_map.entry(lhs.clone()) {
+            Entry::Occupied(o) => o.get().clone(),
+            Entry::Vacant(v) => v.insert(self.tree.type_of_node(lhs)).clone(),
+        };
+        let right_t = match self.type_map.entry(rhs.clone()) {
+            Entry::Occupied(o) => o.get().clone(),
+            Entry::Vacant(v) => v.insert(self.tree.type_of_node(rhs)).clone(),
+        };
+        match left_t.equal_type(&right_t) {
+            Some(t) => {
+                if left_t == Type::ComptimeNumber {
+                    self.type_map.insert(lhs, t.clone());
+                }
+                if right_t == Type::ComptimeNumber {
+                    self.type_map.insert(rhs, t.clone());
+                }
+
+                t
+            }
+            None => {
+                eprintln!(
+                    "incompatible types %{}: {left_t:?} and %{}: {right_t:?}!",
+                    lhs.get(),
+                    rhs.get()
+                );
+                Type::void()
+            }
         }
-        t_lhs
     }
 }
 
@@ -446,6 +508,9 @@ impl IR {
                     ast_node.get()
                 )?;
             }
+            Inst::ExplicitCast { node: lhs, ty } => {
+                writeln_indented!(indent, w, "%{} = explicit_cast %{} to {}", node, lhs, ty)?;
+            }
         }
         Ok(())
     }
@@ -468,7 +533,7 @@ mod tests {
     fn ir() {
         let src = "
 fn main() -> u32 {
-    let a: u32 = 0 + 3;
+    let a: u32 = 0 + 3u32;
     let ptr_a = &a;
     return *ptr_a * global;
 }