X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fprogramcompiler.cpp;h=a730f74348f072fab4edd1398835b380b4295af4;hb=f9b23e69b63cbbeed8eeb605c0dc491002a4c23b;hp=b08f1737e4d542610d1a9401f37ac3df90e580cd;hpb=6e6ee01b68056b23c6709d7f60396710dd7623b9;p=libs%2Fgl.git

diff --git a/source/programcompiler.cpp b/source/programcompiler.cpp
index b08f1737..a730f743 100644
--- a/source/programcompiler.cpp
+++ b/source/programcompiler.cpp
@@ -1,3 +1,4 @@
+#include <msp/core/raii.h>
 #include <msp/strings/format.h>
 #include <msp/strings/utils.h>
 #include "error.h"
@@ -7,6 +8,26 @@
 
 using namespace std;
 
+namespace {
+
+const char builtins_src[] =
+	"////// vertex\n"
+	"out gl_PerVertex {\n"
+	"  vec4 gl_Position;\n"
+	"  float gl_ClipDistance[];\n"
+	"};"
+	"////// geometry\n"
+	"in gl_PerVertex {\n"
+	"  vec4 gl_Position;\n"
+	"  float gl_ClipDistance[];\n"
+	"} gl_in[];\n"
+	"out gl_PerVertex {\n"
+	"  vec4 gl_Position;\n"
+	"  float gl_ClipDistance[];\n"
+	"};\n";
+
+}
+
 namespace Msp {
 namespace GL {
 
@@ -19,11 +40,13 @@ ProgramCompiler::ProgramCompiler():
 void ProgramCompiler::compile(const string &source)
 {
 	module = &parser.parse(source);
+	process();
 }
 
 void ProgramCompiler::compile(IO::Base &io)
 {
 	module = &parser.parse(io);
+	process();
 }
 
 void ProgramCompiler::add_shaders(Program &program)
@@ -31,13 +54,16 @@ void ProgramCompiler::add_shaders(Program &program)
 	if(!module)
 		throw invalid_operation("ProgramCompiler::add_shaders");
 
-	string global_source = "#version 150\n"+format_context(module->global_context);
-	if(module->vertex_context.present)
-		program.attach_shader_owned(new VertexShader(global_source+"\n"+format_context(module->vertex_context)));
-	if(module->geometry_context.present)
-		program.attach_shader_owned(new GeometryShader(global_source+"\n"+format_context(module->geometry_context)));
-	if(module->fragment_context.present)
-		program.attach_shader_owned(new FragmentShader(global_source+"\n"+format_context(module->fragment_context)));
+	string head = "#version 150\n";
+	for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
+	{
+		if(i->type==VERTEX)
+			program.attach_shader_owned(new VertexShader(head+create_source(*i)));
+		else if(i->type==GEOMETRY)
+			program.attach_shader_owned(new GeometryShader(head+create_source(*i)));
+		else if(i->type==FRAGMENT)
+			program.attach_shader_owned(new FragmentShader(head+create_source(*i)));
+	}
 
 	program.bind_attribute(VERTEX4, "vertex");
 	program.bind_attribute(NORMAL3, "normal");
@@ -45,57 +71,197 @@ void ProgramCompiler::add_shaders(Program &program)
 	program.bind_attribute(TEXCOORD4, "texcoord");
 }
 
-string ProgramCompiler::format_context(Context &context)
+Module *ProgramCompiler::create_builtins_module()
+{
+	ProgramParser parser;
+	Module *module = new Module(parser.parse(builtins_src));
+	for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
+	{
+		VariableResolver resolver;
+		i->content.visit(resolver);
+		for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
+			j->second->linked_declaration = j->second;
+	}
+	return module;
+}
+
+Module &ProgramCompiler::get_builtins_module()
+{
+	static RefPtr<Module> builtins_module = create_builtins_module();
+	return *builtins_module;
+}
+
+Stage *ProgramCompiler::get_builtins(StageType type)
+{
+	Module &module = get_builtins_module();
+	for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
+		if(i->type==type)
+			return &*i;
+	return 0;
+}
+
+void ProgramCompiler::process()
+{
+	for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
+		generate(*i);
+	for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
+	{
+		if(optimize(*i))
+			i = module->stages.begin();
+		else
+			++i;
+	}
+}
+
+void ProgramCompiler::generate(Stage &stage)
+{
+	inject_block(stage.content, module->shared.content);
+
+	apply<VariableResolver>(stage);
+	apply<InterfaceGenerator>(stage);
+	apply<VariableResolver>(stage);
+	apply<VariableRenamer>(stage);
+}
+
+bool ProgramCompiler::optimize(Stage &stage)
+{
+	UnusedVariableLocator unused_locator;
+	unused_locator.apply(stage);
+
+	NodeRemover remover;
+	remover.to_remove = unused_locator.unused_nodes;
+	remover.apply(stage);
+
+	return !unused_locator.unused_nodes.empty();
+}
+
+void ProgramCompiler::inject_block(Block &target, const Block &source)
+{
+	list<NodePtr<Node> >::iterator insert_point = target.body.begin();
+	for(list<NodePtr<Node> >::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
+		target.body.insert(insert_point, (*i)->clone());
+}
+
+template<typename T>
+void ProgramCompiler::apply(Stage &stage)
+{
+	T visitor;
+	visitor.apply(stage);
+}
+
+string ProgramCompiler::create_source(Stage &stage)
 {
 	Formatter formatter;
-	context.content.visit(formatter);
+	formatter.apply(stage);
 	return formatter.formatted;
 }
 
 
+ProgramCompiler::Visitor::Visitor():
+	stage(0)
+{ }
+
+void ProgramCompiler::Visitor::apply(Stage &s)
+{
+	SetForScope<Stage *> set(stage, &s);
+	stage->content.visit(*this);
+}
+
+
 ProgramCompiler::Formatter::Formatter():
 	indent(0),
 	parameter_list(false),
-	else_if(false)
+	else_if(0)
 { }
 
-string ProgramCompiler::Formatter::format_expression(Expression &expr)
+void ProgramCompiler::Formatter::visit(Literal &literal)
 {
-	return join(expr.tokens.begin(), expr.tokens.end(), string());
+	formatted += literal.token;
 }
 
-void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
+void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
+{
+	formatted += '(';
+	parexpr.expression->visit(*this);
+	formatted += ')';
+}
+
+void ProgramCompiler::Formatter::visit(VariableReference &var)
 {
-	formatted += format("%s;", format_expression(expr.expression));
+	formatted += var.name;
 }
 
-void ProgramCompiler::Formatter::visit(Block &block)
+void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
+{
+	memacc.left->visit(*this);
+	formatted += format(".%s", memacc.member);
+}
+
+void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
+{
+	if(unary.prefix)
+		formatted += unary.oper;
+	unary.expression->visit(*this);
+	if(!unary.prefix)
+		formatted += unary.oper;
+}
+
+void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
+{
+	binary.left->visit(*this);
+	formatted += binary.oper;
+	binary.right->visit(*this);
+	formatted += binary.after;
+}
+
+void ProgramCompiler::Formatter::visit(Assignment &assign)
+{
+	assign.left->visit(*this);
+	formatted += format(" %s ", assign.oper);
+	assign.right->visit(*this);
+}
+
+void ProgramCompiler::Formatter::visit(FunctionCall &call)
 {
-	if(block.use_braces)
+	formatted += format("%s(", call.name);
+	for(vector<NodePtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 	{
-		if(else_if)
-		{
-			formatted += '\n';
-			else_if = false;
-		}
-		formatted += format("%s{\n", string(indent*2, ' '));
+		if(i!=call.arguments.begin())
+			formatted += ", ";
+		(*i)->visit(*this);
 	}
+	formatted += ')';
+}
+
+void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
+{
+	expr.expression->visit(*this);
+	formatted += ';';
+}
+
+void ProgramCompiler::Formatter::visit(Block &block)
+{
+	if(else_if)
+		--else_if;
+
+	unsigned brace_indent = indent;
+	bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
+	if(use_braces)
+		formatted += format("%s{\n", string(brace_indent*2, ' '));
 
-	bool change_indent = (!formatted.empty() && !else_if);
-	indent += change_indent;
+	SetForScope<unsigned> set(indent, indent+!formatted.empty());
 	string spaces(indent*2, ' ');
-	for(vector<Node *>::const_iterator i=block.body.begin(); i!=block.body.end(); ++i)
+	for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 	{
 		if(i!=block.body.begin())
 			formatted += '\n';
-		if(!else_if)
-			formatted += spaces;
+		formatted += spaces;
 		(*i)->visit(*this);
+		else_if = 0;
 	}
-	indent -= change_indent;
 
-	if(block.use_braces)
-		formatted += format("\n%s}", string(indent*2, ' '));
+	if(use_braces)
+		formatted += format("\n%s}", string(brace_indent*2, ' '));
 }
 
 void ProgramCompiler::Formatter::visit(Layout &layout)
@@ -125,19 +291,28 @@ void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 		formatted += "const ";
 	if(!var.sampling.empty())
 		formatted += format("%s ", var.sampling);
-	if(!var.interface.empty())
+	if(!var.interface.empty() && var.interface!=block_interface)
 		formatted += format("%s ", var.interface);
 	formatted += format("%s %s", var.type, var.name);
 	if(var.array)
-		formatted += format("[%s]", format_expression(var.array_size));
-	if(!var.init_expression.empty())
-		formatted += format(" = %s", format_expression(var.init_expression));
+	{
+		formatted += '[';
+		if(var.array_size)
+			var.array_size->visit(*this);
+		formatted += ']';
+	}
+	if(var.init_expression)
+	{
+		formatted += " = ";
+		var.init_expression->visit(*this);
+	}
 	if(!parameter_list)
 		formatted += ';';
 }
 
 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 {
+	SetForScope<string> set(block_interface, iface.interface);
 	formatted += format("%s %s\n", iface.interface, iface.name);
 	iface.members.visit(*this);
 	formatted += ';';
@@ -146,14 +321,13 @@ void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 {
 	formatted += format("%s %s(", func.return_type, func.name);
-	parameter_list = true;
-	for(vector<VariableDeclaration *>::const_iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
+	for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 	{
 		if(i!=func.parameters.begin())
 			formatted += ", ";
+		SetFlag set(parameter_list);
 		(*i)->visit(*this);
 	}
-	parameter_list = false;
 	formatted += ')';
 	if(func.definition)
 	{
@@ -167,18 +341,20 @@ void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 void ProgramCompiler::Formatter::visit(Conditional &cond)
 {
 	if(else_if)
-	{
-		formatted += ' ';
-		else_if = false;
-	}
-	formatted += format("if(%s)\n", format_expression(cond.condition));
+		formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
+
+	indent -= else_if;
+
+	formatted += "if(";
+	cond.condition->visit(*this);
+	formatted += ")\n";
+
 	cond.body.visit(*this);
 	if(!cond.else_body.body.empty())
 	{
-		formatted += format("\n%selse", string(indent*2, ' '));
-		else_if = true;
+		formatted += format("\n%selse\n", string(indent*2, ' '));
+		SetForScope<unsigned> set(else_if, 2);
 		cond.else_body.visit(*this);
-		else_if = false;
 	}
 }
 
@@ -186,13 +362,611 @@ void ProgramCompiler::Formatter::visit(Iteration &iter)
 {
 	formatted += "for(";
 	iter.init_statement->visit(*this);
-	formatted += format(" %s; %s)\n", format_expression(iter.condition), format_expression(iter.loop_expression));
+	formatted += ' ';
+	iter.condition->visit(*this);
+	formatted += "; ";
+	iter.loop_expression->visit(*this);
+	formatted += ")\n";
 	iter.body.visit(*this);
 }
 
 void ProgramCompiler::Formatter::visit(Return &ret)
 {
-	formatted += format("return %s;", format_expression(ret.expression));
+	formatted += "return ";
+	ret.expression->visit(*this);
+	formatted += ';';
+}
+
+
+ProgramCompiler::VariableResolver::VariableResolver():
+	anonymous(false),
+	record_target(false),
+	assignment_target(0),
+	self_referencing(false)
+{ }
+
+void ProgramCompiler::VariableResolver::apply(Stage &s)
+{
+	SetForScope<Stage *> set(stage, &s);
+	Stage *builtins = get_builtins(stage->type);
+	if(builtins)
+		blocks.push_back(&builtins->content);
+	stage->content.visit(*this);
+	if(builtins)
+		blocks.pop_back();
+}
+
+void ProgramCompiler::VariableResolver::visit(Block &block)
+{
+	blocks.push_back(&block);
+	block.variables.clear();
+	TraversingVisitor::visit(block);
+	blocks.pop_back();
+}
+
+void ProgramCompiler::VariableResolver::visit(VariableReference &var)
+{
+	var.declaration = 0;
+	type = 0;
+	for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
+	{
+		--i;
+		map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
+		if(j!=(*i)->variables.end())
+		{
+			var.declaration = j->second;
+			type = j->second->type_declaration;
+			break;
+		}
+	}
+
+	if(record_target)
+	{
+		if(assignment_target)
+		{
+			record_target = false;
+			assignment_target = 0;
+		}
+		else
+			assignment_target = var.declaration;
+	}
+	else if(var.declaration && var.declaration==assignment_target)
+		self_referencing = true;
+}
+
+void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
+{
+	type = 0;
+	TraversingVisitor::visit(memacc);
+	memacc.declaration = 0;
+	if(type)
+	{
+		map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
+		if(i!=type->members.variables.end())
+		{
+			memacc.declaration = i->second;
+			type = i->second->type_declaration;
+		}
+		else
+			type = 0;
+	}
+}
+
+void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
+{
+	if(binary.oper=="[")
+	{
+		{
+			SetForScope<bool> set(record_target, false);
+			binary.right->visit(*this);
+		}
+		type = 0;
+		binary.left->visit(*this);
+	}
+	else
+	{
+		TraversingVisitor::visit(binary);
+		type = 0;
+	}
+}
+
+void ProgramCompiler::VariableResolver::visit(Assignment &assign)
+{
+	{
+		SetFlag set(record_target);
+		assignment_target = 0;
+		assign.left->visit(*this);
+	}
+
+	self_referencing = false;
+	assign.right->visit(*this);
+
+	assign.self_referencing = (self_referencing || assign.oper!="=");
+	assign.target_declaration = assignment_target;
+}
+
+void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
+{
+	TraversingVisitor::visit(strct);
+	blocks.back()->types[strct.name] = &strct;
+}
+
+void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
+{
+	for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
+	{
+		--i;
+		map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
+		if(j!=(*i)->types.end())
+			var.type_declaration = j->second;
+	}
+
+	if(!block_interface.empty() && var.interface.empty())
+		var.interface = block_interface;
+
+	TraversingVisitor::visit(var);
+	blocks.back()->variables[var.name] = &var;
+	if(anonymous && blocks.size()>1)
+		blocks[blocks.size()-2]->variables[var.name] = &var;
+}
+
+void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
+{
+	SetFlag set(anonymous);
+	SetForScope<string> set2(block_interface, iface.interface);
+	TraversingVisitor::visit(iface);
+}
+
+
+ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
+	scope_level(0),
+	remove_node(false)
+{ }
+
+string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
+{
+	if(type==VERTEX)
+		return "_vs_out_";
+	else if(type==GEOMETRY)
+		return "_gs_out_";
+	else
+		return string();
+}
+
+void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
+{
+	SetForScope<Stage *> set(stage, &s);
+	if(stage->previous)
+		in_prefix = get_out_prefix(stage->previous->type);
+	out_prefix = get_out_prefix(stage->type);
+	stage->content.visit(*this);
+}
+
+void ProgramCompiler::InterfaceGenerator::visit(Block &block)
+{
+	SetForScope<unsigned> set(scope_level, scope_level+1);
+	for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+	{
+		(*i)->visit(*this);
+
+		if(scope_level==1)
+		{
+			for(map<string, VariableDeclaration *>::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
+			{
+				list<NodePtr<Node> >::iterator k = block.body.insert(i, j->second);
+				(*k)->visit(*this);
+			}
+			iface_declarations.clear();
+		}
+
+		for(list<Node *>::iterator j=insert_nodes.begin(); j!=insert_nodes.end(); ++j)
+			block.body.insert(i, *j);
+		insert_nodes.clear();
+
+		if(remove_node)
+			block.body.erase(i++);
+		else
+			++i;
+		remove_node = false;
+	}
+}
+
+string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
+{
+	unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
+	return prefix+name.substr(offset);
+}
+
+bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
+{
+	const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
+	if(stage_vars.count(name) || iface_declarations.count(name))
+		return false;
+
+	VariableDeclaration* iface_var = new VariableDeclaration;
+	iface_var->sampling = var.sampling;
+	iface_var->interface = iface;
+	iface_var->type = var.type;
+	iface_var->type_declaration = var.type_declaration;
+	iface_var->name = name;
+	if(stage->type==GEOMETRY)
+		iface_var->array = ((var.array && var.interface!="in") || iface=="in");
+	else
+		iface_var->array = var.array;
+	if(iface_var->array)
+		iface_var->array_size = var.array_size;
+	if(iface=="in")
+		iface_var->linked_declaration = &var;
+	iface_declarations[name] = iface_var;
+
+	return true;
+}
+
+void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
+{
+	Assignment *assign = new Assignment;
+	VariableReference *ref = new VariableReference;
+	ref->name = left;
+	assign->left = ref;
+	assign->oper = "=";
+	assign->right = right;
+
+	ExpressionStatement *stmt = new ExpressionStatement;
+	stmt->expression = assign;
+	insert_nodes.push_back(stmt);
+}
+
+void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
+{
+	if(var.declaration || !stage->previous)
+		return;
+	if(iface_declarations.count(var.name))
+		return;
+
+	const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
+	map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
+	if(i==prev_out.end())
+		i = prev_out.find(in_prefix+var.name);
+	if(i!=prev_out.end())
+		generate_interface(*i->second, "in", var.name);
+}
+
+void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
+{
+	if(var.interface=="out")
+	{
+		if(scope_level==1)
+			stage->out_variables[var.name] = &var;
+		else if(generate_interface(var, "out", change_prefix(var.name, string())))
+		{
+			remove_node = true;
+			if(var.init_expression)
+				insert_assignment(var.name, var.init_expression->clone());
+		}
+	}
+	else if(var.interface=="in")
+	{
+		stage->in_variables[var.name] = &var;
+		if(var.linked_declaration)
+			var.linked_declaration->linked_declaration = &var;
+		else if(stage->previous)
+		{
+			const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
+			map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
+			if(i!=prev_out.end())
+			{
+				var.linked_declaration = i->second;
+				i->second->linked_declaration = &var;
+			}
+		}
+	}
+
+	TraversingVisitor::visit(var);
+}
+
+void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
+{
+	vector<VariableDeclaration *> pass_vars;
+
+	for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
+		pass_vars.push_back(i->second);
+	for(map<string, VariableDeclaration *>::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
+		if(i->second->interface=="in")
+			pass_vars.push_back(i->second);
+
+	if(stage->previous)
+	{
+		const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
+		for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
+		{
+			bool linked = false;
+			for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
+				linked = ((*j)->linked_declaration==i->second);
+
+			if(!linked && generate_interface(*i->second, "in", i->second->name))
+				pass_vars.push_back(i->second);
+		}
+	}
+
+	if(stage->type==GEOMETRY)
+	{
+		VariableReference *ref = new VariableReference;
+		ref->name = "gl_in";
+
+		BinaryExpression *subscript = new BinaryExpression;
+		subscript->left = ref;
+		subscript->oper = "[";
+		subscript->right = pass.subscript;
+		subscript->after = "]";
+
+		MemberAccess *memacc = new MemberAccess;
+		memacc->left = subscript;
+		memacc->member = "gl_Position";
+
+		insert_assignment("gl_Position", memacc);
+	}
+
+	for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
+	{
+		string out_name = change_prefix((*i)->name, out_prefix);
+		generate_interface(**i, "out", out_name);
+
+		VariableReference *ref = new VariableReference;
+		ref->name = (*i)->name;
+		if(pass.subscript)
+		{
+			BinaryExpression *subscript = new BinaryExpression;
+			subscript->left = ref;
+			subscript->oper = "[";
+			subscript->right = pass.subscript;
+			subscript->after = "]";
+			insert_assignment(out_name, subscript);
+		}
+		else
+			insert_assignment(out_name, ref);
+	}
+
+	remove_node = true;
+}
+
+
+void ProgramCompiler::VariableRenamer::visit(VariableReference &var)
+{
+	if(var.declaration)
+		var.name = var.declaration->name;
+}
+
+void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
+{
+	if(var.linked_declaration)
+		var.name = var.linked_declaration->name;
+	TraversingVisitor::visit(var);
+}
+
+
+ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
+	aggregate(0),
+	assignment(0),
+	assignment_target(false)
+{ }
+
+void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
+{
+	assignments.push_back(BlockAssignmentMap());
+	Visitor::apply(s);
+	assignments.pop_back();
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
+{
+	unused_nodes.erase(var.declaration);
+
+	map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
+	if(i!=aggregates.end())
+		unused_nodes.erase(i->second);
+
+	if(assignment_target)
+		return;
+
+	for(vector<BlockAssignmentMap>::iterator j=assignments.end(); j!=assignments.begin(); )
+	{
+		--j;
+		BlockAssignmentMap::iterator k = j->find(var.declaration);
+		if(k!=j->end())
+		{
+			for(vector<Node *>::iterator l=k->second.nodes.begin(); l!=k->second.nodes.end(); ++l)
+				unused_nodes.erase(*l);
+			j->erase(k);
+			break;
+		}
+	}
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
+{
+	TraversingVisitor::visit(memacc);
+	unused_nodes.erase(memacc.declaration);
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
+{
+	if(binary.oper=="[")
+	{
+		binary.left->visit(*this);
+		SetForScope<bool> set(assignment_target, false);
+		binary.right->visit(*this);
+	}
+	else
+		TraversingVisitor::visit(binary);
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
+{
+	{
+		SetForScope<bool> set(assignment_target, !assign.self_referencing);
+		assign.left->visit(*this);
+	}
+	assign.right->visit(*this);
+	assignment = &assign;
+}
+
+void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
+{
+	unused_nodes.insert(&node);
+	BlockAssignmentMap &block_assignments = assignments.back();
+	AssignmentList &var_assignments = block_assignments[&var];
+	if(!self_ref)
+		var_assignments.nodes.clear();
+	var_assignments.nodes.push_back(&node);
+	var_assignments.conditional = false;
+	var_assignments.self_referencing = self_ref;
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
+{
+	assignment = 0;
+	TraversingVisitor::visit(expr);
+	if(assignment && assignment->target_declaration)
+		record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
+{
+	SetForScope<Node *> set(aggregate, &strct);
+	unused_nodes.insert(&strct);
+	TraversingVisitor::visit(strct);
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
+{
+	if(aggregate)
+		aggregates[&var] = aggregate;
+	else
+	{
+		unused_nodes.insert(&var);
+		if(var.init_expression)
+			record_assignment(var, *var.init_expression, false);
+	}
+	unused_nodes.erase(var.type_declaration);
+	TraversingVisitor::visit(var);
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
+{
+	SetForScope<Node *> set(aggregate, &iface);
+	unused_nodes.insert(&iface);
+	TraversingVisitor::visit(iface);
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
+{
+	assignments.push_back(BlockAssignmentMap());
+
+	for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
+		(*i)->visit(*this);
+	func.body.visit(*this);
+
+	BlockAssignmentMap &block_assignments = assignments.back();
+	for(map<string, VariableDeclaration *>::iterator i=func.body.variables.begin(); i!=func.body.variables.end(); ++i)
+		block_assignments.erase(i->second);
+	for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
+	{
+		if(i->first->interface=="out" && stage->type!=FRAGMENT && !i->first->linked_declaration)
+			continue;
+
+		for(vector<Node *>::iterator j=i->second.nodes.begin(); j!=i->second.nodes.end(); ++j)
+			unused_nodes.erase(*j);
+	}
+
+	assignments.pop_back();
+}
+
+void ProgramCompiler::UnusedVariableLocator::merge_down_assignments()
+{
+	BlockAssignmentMap &parent_assignments = assignments[assignments.size()-2];
+	BlockAssignmentMap &block_assignments = assignments.back();
+	for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
+	{
+		BlockAssignmentMap::iterator j = parent_assignments.find(i->first);
+		if(j==parent_assignments.end())
+			parent_assignments.insert(*i);
+		else if(i->second.self_referencing || i->second.conditional)
+		{
+			j->second.nodes.insert(j->second.nodes.end(), i->second.nodes.begin(), i->second.nodes.end());
+			j->second.conditional |= i->second.conditional;
+			j->second.self_referencing |= i->second.self_referencing;
+		}
+		else
+			j->second = i->second;
+	}
+	assignments.pop_back();
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
+{
+	cond.condition->visit(*this);
+	assignments.push_back(BlockAssignmentMap());
+	cond.body.visit(*this);
+
+	BlockAssignmentMap if_assignments;
+	swap(assignments.back(), if_assignments);
+	cond.else_body.visit(*this);
+
+	BlockAssignmentMap &else_assignments = assignments.back();
+	for(BlockAssignmentMap::iterator i=else_assignments.begin(); i!=else_assignments.end(); ++i)
+	{
+		BlockAssignmentMap::iterator j = if_assignments.find(i->first);
+		if(j!=if_assignments.end())
+		{
+			i->second.nodes.insert(i->second.nodes.end(), j->second.nodes.begin(), j->second.nodes.end());
+			i->second.conditional |= j->second.conditional;
+			i->second.self_referencing |= j->second.self_referencing;
+			if_assignments.erase(j);
+		}
+		else
+			i->second.conditional = true;
+	}
+
+	for(BlockAssignmentMap::iterator i=if_assignments.begin(); i!=if_assignments.end(); ++i)
+	{
+		i->second.conditional = true;
+		else_assignments.insert(*i);
+	}
+
+	merge_down_assignments();
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
+{
+	assignments.push_back(BlockAssignmentMap());
+	TraversingVisitor::visit(iter);
+	merge_down_assignments();
+}
+
+
+void ProgramCompiler::NodeRemover::visit(Block &block)
+{
+	for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+	{
+		(*i)->visit(*this);
+		if(to_remove.count(&**i))
+			block.body.erase(i++);
+		else
+			++i;
+	}
+}
+
+void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
+{
+	if(to_remove.count(&var))
+	{
+		stage->in_variables.erase(var.name);
+		stage->out_variables.erase(var.name);
+		if(var.linked_declaration)
+			var.linked_declaration->linked_declaration = 0;
+	}
+	else if(var.init_expression && to_remove.count(&*var.init_expression))
+		var.init_expression = 0;
 }
 
 } // namespace GL