Starting work on IR.

dmc-lib/src/ast/call.rs

@@ -1,5 +1,8 @@
 use crate::ast::expression::Expression;
+use crate::ast::function::FunctionLoweringContext;
 use crate::diagnostic::Diagnostic;
+use crate::ir::ir_call::IrCall;
+use crate::ir::ir_expression::IrExpression;
 use crate::source_range::SourceRange;
 use crate::symbol_table::SymbolTable;
 use crate::type_info::TypeInfo;
@@ -74,6 +77,19 @@ impl Call {
         }
     }
 
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) -> IrExpression {
+        let function_name = match self.callee() {
+            Expression::Identifier(identifier) => identifier.name(),
+            _ => panic!("Calling things other than identifiers not yet supported."),
+        };
+        let arguments = self
+            .arguments()
+            .iter()
+            .map(|arg| arg.lower_to_ir(context))
+            .collect();
+        IrExpression::Call(IrCall::new(function_name, arguments))
+    }
+
     pub fn source_range(&self) -> &SourceRange {
         &self.source_range
     }

dmc-lib/src/ast/compilation_unit.rs

@@ -1,5 +1,6 @@
 use crate::ast::function::Function;
 use crate::diagnostic::Diagnostic;
+use crate::ir::Ir;
 use crate::symbol_table::SymbolTable;
 
 pub struct CompilationUnit {
@@ -40,4 +41,12 @@ impl CompilationUnit {
         }
         diagnostics
     }
+
+    pub fn lower_to_ir(&self) -> Vec<Ir> {
+        let mut irs = vec![];
+        for function in &self.functions {
+            irs.append(&mut function.lower_to_ir());
+        }
+        irs
+    }
 }

dmc-lib/src/ast/expression.rs

@@ -1,8 +1,10 @@
 use crate::ast::call::Call;
+use crate::ast::function::FunctionLoweringContext;
 use crate::ast::identifier::Identifier;
 use crate::ast::integer_literal::IntegerLiteral;
 use crate::ast::string_literal::StringLiteral;
 use crate::diagnostic::Diagnostic;
+use crate::ir::ir_expression::IrExpression;
 use crate::source_range::SourceRange;
 use crate::symbol_table::SymbolTable;
 use crate::type_info::TypeInfo;
@@ -55,4 +57,13 @@ impl Expression {
             Expression::Identifier(identifier) => identifier.source_range(),
         }
     }
+
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) -> IrExpression {
+        match self {
+            Expression::Call(call) => call.lower_to_ir(context),
+            Expression::IntegerLiteral(integer_literal) => integer_literal.lower_to_ir(context),
+            Expression::String(string_literal) => string_literal.lower_to_ir(context),
+            Expression::Identifier(identifier) => identifier.lower_to_ir(context),
+        }
+    }
 }

dmc-lib/src/ast/expression_statement.rs

@@ -0,0 +1,38 @@
+use crate::ast::expression::Expression;
+use crate::ast::function::FunctionLoweringContext;
+use crate::diagnostic::Diagnostic;
+use crate::ir::ir_statement::IrStatement;
+use crate::symbol_table::SymbolTable;
+
+pub struct ExpressionStatement {
+    expression: Box<Expression>,
+}
+
+impl ExpressionStatement {
+    pub fn new(expression: Expression) -> Self {
+        Self {
+            expression: expression.into(),
+        }
+    }
+
+    pub fn expression(&self) -> &Expression {
+        &self.expression
+    }
+
+    pub fn gather_declared_names(&mut self, symbol_table: &mut SymbolTable) -> Vec<Diagnostic> {
+        self.expression.gather_declared_names(symbol_table)
+    }
+
+    pub fn check_name_usages(&mut self, symbol_table: &SymbolTable) -> Vec<Diagnostic> {
+        self.expression.check_name_usages(symbol_table)
+    }
+
+    pub fn type_check(&mut self, symbol_table: &SymbolTable) -> Vec<Diagnostic> {
+        self.expression.type_check(symbol_table)
+    }
+
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) {
+        let ir_expression = self.expression.lower_to_ir(context);
+        context.add_statement(IrStatement::Expression(ir_expression));
+    }
+}

dmc-lib/src/ast/fqn.rs

@@ -0,0 +1,15 @@
+pub struct Fqn {
+    parts: Vec<String>,
+}
+
+impl Fqn {
+    pub fn new(parts: &[&str]) -> Self {
+        Self {
+            parts: parts.iter().map(|s| s.to_string()).collect(),
+        }
+    }
+
+    pub fn parts(&self) -> &[String] {
+        self.parts.as_slice()
+    }
+}

dmc-lib/src/ast/function.rs

@@ -1,5 +1,9 @@
 use crate::ast::statement::Statement;
 use crate::diagnostic::Diagnostic;
+use crate::ir::Ir;
+use crate::ir::ir_constant::IrConstant;
+use crate::ir::ir_function::IrFunction;
+use crate::ir::ir_statement::IrStatement;
 use crate::source_range::SourceRange;
 use crate::symbol::FunctionSymbol;
 use crate::symbol_table::{SymbolInsertError, SymbolTable};
@@ -75,4 +79,64 @@ impl Function {
         }
         diagnostics
     }
+
+    pub fn lower_to_ir(&self) -> Vec<Ir> {
+        let mut context = FunctionLoweringContext::new();
+        for statement in &self.statements {
+            statement.lower_to_ir(&mut context);
+        }
+        let mut irs = vec![];
+        for constant in context.take_constants() {
+            irs.push(Ir::Constant(constant));
+        }
+        let ir_function = IrFunction::new(context.take_statements());
+        irs.push(Ir::Function(ir_function));
+        irs
+    }
+}
+
+pub struct FunctionLoweringContext {
+    temp_variable_counter: usize,
+    constant_counter: usize,
+    constants: Vec<IrConstant>,
+    statements: Vec<IrStatement>,
+}
+
+impl FunctionLoweringContext {
+    pub fn new() -> Self {
+        Self {
+            temp_variable_counter: 0,
+            constant_counter: 0,
+            constants: vec![],
+            statements: vec![],
+        }
+    }
+
+    pub fn next_temp_variable(&mut self) -> String {
+        let temp_variable = format!("t_{}", self.temp_variable_counter);
+        self.temp_variable_counter += 1;
+        temp_variable
+    }
+
+    pub fn next_constant_name(&mut self) -> String {
+        let constant_name = format!("%const_{}", self.constant_counter);
+        self.constant_counter += 1;
+        constant_name
+    }
+
+    pub fn add_constant(&mut self, constant: IrConstant) {
+        self.constants.push(constant);
+    }
+
+    pub fn take_constants(&mut self) -> Vec<IrConstant> {
+        std::mem::take(&mut self.constants)
+    }
+
+    pub fn add_statement(&mut self, statement: IrStatement) {
+        self.statements.push(statement);
+    }
+
+    pub fn take_statements(&mut self) -> Vec<IrStatement> {
+        std::mem::take(&mut self.statements)
+    }
 }

dmc-lib/src/ast/identifier.rs

@@ -1,4 +1,7 @@
+use crate::ast::function::FunctionLoweringContext;
 use crate::diagnostic::Diagnostic;
+use crate::ir::ir_expression::IrExpression;
+use crate::ir::ir_variable::IrVariable;
 use crate::source_range::SourceRange;
 use crate::symbol::ExpressibleSymbol;
 use crate::symbol_table::SymbolTable;
@@ -58,6 +61,10 @@ impl Identifier {
         }
     }
 
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) -> IrExpression {
+        IrExpression::Variable(IrVariable::new(self.name()))
+    }
+
     pub fn source_range(&self) -> &SourceRange {
         &self.source_range
     }

dmc-lib/src/ast/integer_literal.rs

@@ -1,3 +1,5 @@
+use crate::ast::function::FunctionLoweringContext;
+use crate::ir::ir_expression::IrExpression;
 use crate::source_range::SourceRange;
 
 pub struct IntegerLiteral {
@@ -17,6 +19,10 @@ impl IntegerLiteral {
         self.value
     }
 
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) -> IrExpression {
+        IrExpression::IntegerLiteral(self.value)
+    }
+
     pub fn source_range(&self) -> &SourceRange {
         &self.source_range
     }

dmc-lib/src/ast/let_statement.rs

@@ -1,5 +1,9 @@
 use crate::ast::expression::Expression;
+use crate::ast::function::FunctionLoweringContext;
 use crate::diagnostic::Diagnostic;
+use crate::ir::ir_assign::IrAssign;
+use crate::ir::ir_statement::IrStatement;
+use crate::ir::ir_variable::IrVariable;
 use crate::source_range::SourceRange;
 use crate::symbol::VariableSymbol;
 use crate::symbol_table::{SymbolInsertError, SymbolTable};
@@ -68,4 +72,11 @@ impl LetStatement {
         diagnostics.append(&mut self.initializer.type_check(symbol_table));
         diagnostics
     }
+
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) {
+        let data = self.initializer.lower_to_ir(context);
+        let destination = IrVariable::new(self.declared_name());
+        let assign_statement = IrAssign::new(destination, data);
+        context.add_statement(IrStatement::Assign(assign_statement));
+    }
 }

dmc-lib/src/ast/mod.rs

@@ -1,6 +1,8 @@
 pub mod call;
 pub mod compilation_unit;
 pub mod expression;
+pub mod expression_statement;
+pub mod fqn;
 pub mod function;
 pub mod identifier;
 pub mod integer_literal;
@@ -25,6 +27,24 @@ mod name_tests {
             0
         );
         assert_eq!(compilation_unit.check_name_usages(&symbol_table).len(), 0);
+        let irs = compilation_unit.lower_to_ir();
+        for ir in &irs {
+            println!("{:#?}", ir);
+        }
+    }
+
+    #[test]
+    fn hello_world() {
+        let mut symbol_table = SymbolTable::new();
+        let mut compilation_unit =
+            parse_compilation_unit("fn println() end fn main() println(\"Hello, World!\") end");
+        compilation_unit.gather_declared_names(&mut symbol_table);
+        compilation_unit.check_name_usages(&symbol_table);
+        compilation_unit.type_check(&symbol_table);
+        let irs = compilation_unit.lower_to_ir();
+        for ir in &irs {
+            println!("{:#?}", ir);
+        }
     }
 
     #[test]

dmc-lib/src/ast/statement.rs

@@ -1,32 +1,50 @@
-use crate::ast::expression::Expression;
+use crate::ast::expression_statement::ExpressionStatement;
+use crate::ast::function::FunctionLoweringContext;
 use crate::ast::let_statement::LetStatement;
 use crate::diagnostic::Diagnostic;
 use crate::symbol_table::SymbolTable;
 
 pub enum Statement {
     Let(LetStatement),
-    Expression(Expression),
+    Expression(ExpressionStatement),
 }
 
 impl Statement {
     pub fn gather_declared_names(&mut self, symbol_table: &mut SymbolTable) -> Vec<Diagnostic> {
         match self {
             Statement::Let(let_statement) => let_statement.gather_declared_names(symbol_table),
-            Statement::Expression(expression) => expression.gather_declared_names(symbol_table),
+            Statement::Expression(expression_statement) => {
+                expression_statement.gather_declared_names(symbol_table)
+            }
         }
     }
 
     pub fn check_name_usages(&mut self, symbol_table: &SymbolTable) -> Vec<Diagnostic> {
         match self {
             Statement::Let(let_statement) => let_statement.check_name_usages(symbol_table),
-            Statement::Expression(expression) => expression.check_name_usages(symbol_table),
+            Statement::Expression(expression_statement) => {
+                expression_statement.check_name_usages(symbol_table)
+            }
         }
     }
 
     pub fn type_check(&mut self, symbol_table: &SymbolTable) -> Vec<Diagnostic> {
         match self {
             Statement::Let(let_statement) => let_statement.type_check(symbol_table),
-            Statement::Expression(expression) => expression.type_check(symbol_table),
+            Statement::Expression(expression_statement) => {
+                expression_statement.type_check(symbol_table)
+            }
+        }
+    }
+
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) {
+        match self {
+            Statement::Let(let_statement) => {
+                let_statement.lower_to_ir(context);
+            }
+            Statement::Expression(expression) => {
+                expression.lower_to_ir(context);
+            }
         }
     }
 }

dmc-lib/src/ast/string_literal.rs

@@ -1,4 +1,8 @@
+use crate::ast::function::FunctionLoweringContext;
+use crate::ir::ir_constant::{IrConstant, IrStringConstant};
+use crate::ir::ir_expression::IrExpression;
 use crate::source_range::SourceRange;
+use std::rc::Rc;
 
 pub struct StringLiteral {
     content: String,
@@ -17,6 +21,15 @@ impl StringLiteral {
         &self.content
     }
 
+    pub fn lower_to_ir(&self, context: &mut FunctionLoweringContext) -> IrExpression {
+        let ir_string_constant = Rc::new(IrStringConstant::new(
+            self.content(),
+            &context.next_constant_name(),
+        ));
+        context.add_constant(IrConstant::String(ir_string_constant.clone()));
+        IrExpression::Constant(IrConstant::String(ir_string_constant))
+    }
+
     pub fn source_range(&self) -> &SourceRange {
         &self.source_range
     }

dmc-lib/src/ir/ir_assign.rs

@@ -0,0 +1,17 @@
+use crate::ir::ir_expression::IrExpression;
+use crate::ir::ir_variable::IrVariable;
+
+#[derive(Debug)]
+pub struct IrAssign {
+    destination: Box<IrVariable>,
+    value: Box<IrExpression>,
+}
+
+impl IrAssign {
+    pub fn new(destination: IrVariable, value: IrExpression) -> Self {
+        Self {
+            destination: destination.into(),
+            value: value.into(),
+        }
+    }
+}

dmc-lib/src/ir/ir_call.rs

@@ -0,0 +1,16 @@
+use crate::ir::ir_expression::IrExpression;
+
+#[derive(Debug)]
+pub struct IrCall {
+    name: String,
+    arguments: Vec<IrExpression>,
+}
+
+impl IrCall {
+    pub fn new(name: &str, arguments: Vec<IrExpression>) -> Self {
+        Self {
+            name: name.into(),
+            arguments,
+        }
+    }
+}

dmc-lib/src/ir/ir_constant.rs

@@ -0,0 +1,21 @@
+use std::rc::Rc;
+
+#[derive(Debug)]
+pub enum IrConstant {
+    String(Rc<IrStringConstant>),
+}
+
+#[derive(Debug)]
+pub struct IrStringConstant {
+    value: String,
+    name: String,
+}
+
+impl IrStringConstant {
+    pub fn new(value: &str, name: &str) -> Self {
+        Self {
+            value: value.into(),
+            name: name.into(),
+        }
+    }
+}

dmc-lib/src/ir/ir_expression.rs

@@ -0,0 +1,11 @@
+use crate::ir::ir_call::IrCall;
+use crate::ir::ir_constant::IrConstant;
+use crate::ir::ir_variable::IrVariable;
+
+#[derive(Debug)]
+pub enum IrExpression {
+    Call(IrCall),
+    Constant(IrConstant),
+    IntegerLiteral(i64),
+    Variable(IrVariable),
+}

dmc-lib/src/ir/ir_function.rs

@@ -0,0 +1,12 @@
+use crate::ir::ir_statement::IrStatement;
+
+#[derive(Debug)]
+pub struct IrFunction {
+    statements: Vec<IrStatement>,
+}
+
+impl IrFunction {
+    pub fn new(statements: Vec<IrStatement>) -> Self {
+        Self { statements }
+    }
+}

dmc-lib/src/ir/ir_l_value.rs

@@ -0,0 +1,6 @@
+use crate::ir::ir_variable::IrVariable;
+
+pub enum IrLhs {
+    Variable(IrVariable),
+    FunctionName(String),
+}

dmc-lib/src/ir/ir_r_value.rs

@@ -0,0 +1,8 @@
+use crate::ir::ir_constant::IrConstant;
+use crate::ir::ir_variable::IrVariable;
+
+pub enum IrRhs {
+    Constant(IrConstant),
+    IntegerLiteral(i64),
+    Variable(IrVariable),
+}

dmc-lib/src/ir/ir_statement.rs

@@ -0,0 +1,8 @@
+use crate::ir::ir_assign::IrAssign;
+use crate::ir::ir_expression::IrExpression;
+
+#[derive(Debug)]
+pub enum IrStatement {
+    Assign(IrAssign),
+    Expression(IrExpression),
+}

dmc-lib/src/ir/ir_variable.rs

@@ -0,0 +1,10 @@
+#[derive(Debug)]
+pub struct IrVariable {
+    name: String,
+}
+
+impl IrVariable {
+    pub fn new(name: &str) -> Self {
+        Self { name: name.into() }
+    }
+}

dmc-lib/src/ir/mod.rs

@@ -0,0 +1,18 @@
+use crate::ir::ir_constant::IrConstant;
+use crate::ir::ir_function::IrFunction;
+
+pub mod ir_assign;
+pub mod ir_call;
+pub mod ir_constant;
+pub mod ir_expression;
+pub mod ir_function;
+pub mod ir_l_value;
+pub mod ir_r_value;
+pub mod ir_statement;
+pub mod ir_variable;
+
+#[derive(Debug)]
+pub enum Ir {
+    Function(IrFunction),
+    Constant(IrConstant),
+}

dmc-lib/src/lib.rs

@@ -1,5 +1,6 @@
 mod ast;
 mod diagnostic;
+mod ir;
 mod lexer;
 mod parser;
 mod scope;

dmc-lib/src/parser.rs

@@ -1,6 +1,7 @@
 use crate::ast::call::Call;
 use crate::ast::compilation_unit::CompilationUnit;
 use crate::ast::expression::Expression;
+use crate::ast::expression_statement::ExpressionStatement;
 use crate::ast::function::Function;
 use crate::ast::identifier::Identifier;
 use crate::ast::integer_literal::IntegerLiteral;
@@ -169,7 +170,7 @@ impl<'a> Parser<'a> {
     }
 
     fn expression_statement(&mut self) -> Statement {
-        Statement::Expression(self.expression())
+        Statement::Expression(ExpressionStatement::new(self.expression()))
     }
 
     fn expression(&mut self) -> Expression {
@@ -246,8 +247,8 @@ mod smoke_tests {
         assert_eq!(function.declared_name(), "main");
         let statements = function.statements();
         assert_eq!(statements.len(), 1);
-        if let Statement::Expression(expression) = statements[0] {
-            if let Expression::Call(call) = expression {
+        if let Statement::Expression(expression_statement) = statements[0] {
+            if let Expression::Call(call) = expression_statement.expression() {
                 let callee = call.callee();
                 match callee {
                     Expression::Identifier(identifier) => {