diff options
Diffstat (limited to 'src/compiler.rs')
| -rw-r--r-- | src/compiler.rs | 159 |
1 files changed, 133 insertions, 26 deletions
diff --git a/src/compiler.rs b/src/compiler.rs index 1a6cfc6..ad97783 100644 --- a/src/compiler.rs +++ b/src/compiler.rs @@ -79,7 +79,7 @@ impl From<&Value> for Type { Value::Float(_) => Type::Float, Value::Bool(_) => Type::Bool, Value::String(_) => Type::String, - Value::Function(block) => block.ty.clone(), + Value::Function(_, block) => block.ty.clone(), _ => Type::Void, } } @@ -94,24 +94,69 @@ impl Type { Type::Float => Value::Float(1.0), Type::Bool => Value::Bool(true), Type::String => Value::String(Rc::new("".to_string())), - Type::Function(_, _) => Value::Function(Rc::new(Block::from_type(self))), + Type::Function(_, _) => Value::Function( + Vec::new(), + Rc::new(Block::from_type(self))), } } } +#[derive(Clone)] struct Variable { name: String, typ: Type, scope: usize, + slot: usize, + + outer_slot: usize, + outer_upvalue: bool, + active: bool, + upvalue: bool, + captured: bool, } struct Frame { stack: Vec<Variable>, + upvalues: Vec<Variable>, scope: usize, variables_below: usize, } +impl Frame { + fn find_local(&self, name: &str) -> Option<Variable> { + for var in self.stack.iter().rev() { + if var.name == name && var.active { + return Some(var.clone()); + } + } + None + } + + fn find_upvalue(&self, name: &str) -> Option<Variable> { + for var in self.upvalues.iter().rev() { + if var.name == name && var.active { + return Some(var.clone()); + } + } + None + } + + fn add_upvalue(&mut self, variable: Variable) -> Variable { + println!("{} - UPDOG", variable.name); + let new_variable = Variable { + outer_upvalue: variable.upvalue, + outer_slot: variable.slot, + slot: self.upvalues.len(), + active: true, + upvalue: true, + ..variable + }; + self.upvalues.push(new_variable.clone()); + new_variable + } +} + struct Compiler { curr: usize, tokens: TokenStream, @@ -130,6 +175,7 @@ macro_rules! push_frame { { $compiler.frames.push(Frame { stack: Vec::new(), + upvalues: Vec::new(), scope: 0, variables_below: $compiler.frame().variables_below + $compiler.stack().len(), }); @@ -154,8 +200,13 @@ macro_rules! push_scope { $code; $compiler.frame_mut().scope -= 1; - for _ in ss..$compiler.stack().len() { - $block.add(Op::Pop, $compiler.line()); + + for var in $compiler.frame().stack[ss..$compiler.stack().len()].iter().rev() { + if var.captured { + $block.add(Op::PopUpvalue, $compiler.line()); + } else { + $block.add(Op::Pop, $compiler.line()); + } } $compiler.stack_mut().truncate(ss); }; @@ -170,6 +221,7 @@ impl Compiler { frames: vec![Frame { stack: Vec::new(), + upvalues: Vec::new(), scope: 0, variables_below: 0, }], @@ -388,16 +440,36 @@ impl Compiler { } } - fn find_local(&self, name: &str, _block: &Block) -> Option<(usize, Type, usize)> { - let frame = self.frame(); - for (slot, var) in frame.stack.iter().enumerate().rev() { - if var.name == name && var.active { - return Some((slot, var.typ.clone(), var.scope)); + fn find_and_capture_variable<'a, I>(name: &str, mut iterator: I) -> Option<Variable> + where I: Iterator<Item = &'a mut Frame> { + if let Some(frame) = iterator.next() { + if let Some(res) = frame.find_local(name) { + frame.stack[res.slot].captured = true; + return Some(res); + } + if let Some(res) = frame.find_upvalue(name) { + return Some(res); + } + + if let Some(res) = Self::find_and_capture_variable(name, iterator) { + return Some(frame.add_upvalue(res)); } } None } + fn find_variable(&mut self, name: &str) -> Option<Variable> { + if let Some(res) = self.frame().find_local(name) { + return Some(res); + } + + if let Some(res) = self.frame().find_upvalue(name) { + return Some(res); + } + + return Self::find_and_capture_variable(name, self.frames.iter_mut().rev()); + } + fn call(&mut self, block: &mut Block) { expect!(self, Token::LeftParen, "Expected '(' at start of function call."); @@ -423,17 +495,15 @@ impl Compiler { } block.add(Op::Call(arity), self.line()); - - for _ in 0..arity { - block.add(Op::Pop, self.line()); - } } fn function(&mut self, block: &mut Block) { expect!(self, Token::Fn, "Expected 'fn' at start of function."); - let name = if !self.stack()[self.stack().len() - 1].active { - &self.stack()[self.stack().len() - 1].name + let top = self.stack().len() - 1; + let name = if !self.stack()[top].active { + self.stack_mut()[top].active = true; + &self.stack()[top].name } else { "anonumus function" }; @@ -441,6 +511,7 @@ impl Compiler { let mut args = Vec::new(); let mut return_type = Type::Void; let mut function_block = Block::new(name, &self.current_file, self.line()); + let _ret = push_frame!(self, function_block, { loop { match self.peek() { @@ -479,17 +550,35 @@ impl Compiler { } self.scope(&mut function_block); + + for var in self.frame().upvalues.iter() { + function_block.ups.push((var.outer_slot, var.outer_upvalue, var.typ.clone())); + } + println!("{:?}", function_block.ups); + // TODO(ed): Send the original place to find the upvalues, + // so we know from where to copy them. }); - if !matches!(function_block.last_op(), Some(&Op::Return)) { - function_block.add(Op::Constant(Value::Nil), self.line()); - function_block.add(Op::Return, self.line()); + let mut prev = function_block.ops.len() - 1; + loop { + match function_block.ops[prev] { + Op::Pop | Op::PopUpvalue => {} + Op::Return => { break; } , + _ => { + function_block.add(Op::Constant(Value::Nil), self.line()); + function_block.add(Op::Return, self.line()); + break; + } + } + prev -= 1; } function_block.ty = Type::Function(args, Box::new(return_type)); let function_block = Rc::new(function_block); - block.add(Op::Constant(Value::Function(Rc::clone(&function_block))), self.line()); + + let func = Op::Constant(Value::Function(Vec::new(), Rc::clone(&function_block))); + block.add(func, self.line()); self.blocks.push(function_block); } @@ -498,16 +587,20 @@ impl Compiler { Token::Identifier(name) => name, __ => unreachable!(), }; - if let Some((slot, _, _)) = self.find_local(&name, block) { - block.add(Op::ReadLocal(slot), self.line()); + if let Some(var) = self.find_variable(&name) { + if var.upvalue { + block.add(Op::ReadUpvalue(var.slot), self.line()); + } else { + block.add(Op::ReadLocal(var.slot), self.line()); + } } else { error!(self, format!("Using undefined variable {}.", name)); } } fn define_variable(&mut self, name: &str, typ: Type, block: &mut Block) -> Result<usize, ()> { - if let Some((_, _, level)) = self.find_local(&name, block) { - if level == self.frame().scope { + if let Some(var) = self.find_variable(&name) { + if var.scope == self.frame().scope { error!(self, format!("Multiple definitions of {} in this block.", name)); return Err(()); } @@ -517,9 +610,14 @@ impl Compiler { let scope = self.frame().scope; self.stack_mut().push(Variable { name: String::from(name), + captured: false, + outer_upvalue: false, + outer_slot: 0, + slot, typ, scope, - active: false + active: false, + upvalue: false, }); Ok(slot) } @@ -535,9 +633,13 @@ impl Compiler { } fn assign(&mut self, name: &str, block: &mut Block) { - if let Some((slot, _, _)) = self.find_local(&name, block) { + if let Some(var) = self.find_variable(&name) { self.expression(block); - block.add(Op::Assign(slot), self.line()); + if var.upvalue { + block.add(Op::AssignUpvalue(var.slot), self.line()); + } else { + block.add(Op::AssignLocal(var.slot), self.line()); + } } else { error!(self, format!("Using undefined variable {}.", name)); } @@ -747,8 +849,13 @@ impl Compiler { self.stack_mut().push(Variable { name: String::from("/main/"), typ: Type::Void, + outer_upvalue: false, + outer_slot: 0, + slot: 0, scope: 0, active: false, + captured: false, + upvalue: false, }); let mut block = Block::new(name, file, 0); |