X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=blobdiff_plain;f=source%2Fprogramcompiler.cpp;h=5bb84269f30abe4fcd38198cef0b6a2ae416b2f8;hp=d518ef3aa5fb6d8fd93c8cace2cc71502f771eba;hb=3c46227c280bc4cd8a4487c648f2f080d5b4f7ea;hpb=77e3e702d39a2547a99dd12eea7906d124ba5477

diff --git a/source/programcompiler.cpp b/source/programcompiler.cpp
index d518ef3a..5bb84269 100644
--- a/source/programcompiler.cpp
+++ b/source/programcompiler.cpp
@@ -1,109 +1,261 @@
 #include <msp/core/raii.h>
+#include <msp/gl/extensions/ext_gpu_shader4.h>
 #include <msp/strings/format.h>
 #include <msp/strings/utils.h>
 #include "error.h"
 #include "program.h"
 #include "programcompiler.h"
+#include "resources.h"
 #include "shader.h"
 
 using namespace std;
 
+namespace {
+
+const char builtins_src[] =
+	"#pragma MSP stage(vertex)\n"
+	"out gl_PerVertex {\n"
+	"  vec4 gl_Position;\n"
+	"  float gl_ClipDistance[];\n"
+	"};\n"
+	"#pragma MSP stage(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 {
 
 using namespace ProgramSyntax;
 
+// XXX For some reason global declarations are emitted for otherwise undeclared local variables
+
 ProgramCompiler::ProgramCompiler():
+	resources(0),
 	module(0)
 { }
 
-void ProgramCompiler::compile(const string &source)
+ProgramCompiler::~ProgramCompiler()
 {
-	module = &parser.parse(source);
+	delete module;
+}
+
+void ProgramCompiler::compile(const string &source, const string &src_name)
+{
+	resources = 0;
+	delete module;
+	module = new Module();
+	ProgramParser parser;
+	imported_names.insert(src_name);
+	append_module(parser.parse(source, src_name));
 	process();
 }
 
-void ProgramCompiler::compile(IO::Base &io)
+void ProgramCompiler::compile(IO::Base &io, Resources *res, const string &src_name)
 {
-	module = &parser.parse(io);
+	resources = res;
+	delete module;
+	module = new Module();
+	ProgramParser parser;
+	imported_names.insert(src_name);
+	append_module(parser.parse(io, src_name));
 	process();
 }
 
+void ProgramCompiler::compile(IO::Base &io, const string &src_name)
+{
+	compile(io, 0, src_name);
+}
+
 void ProgramCompiler::add_shaders(Program &program)
 {
 	if(!module)
 		throw invalid_operation("ProgramCompiler::add_shaders");
 
-	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)));
+		{
+			program.attach_shader_owned(new VertexShader(apply<Formatter>(*i)));
+			for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
+				program.bind_attribute(j->second, j->first);
+		}
 		else if(i->type==GEOMETRY)
-			program.attach_shader_owned(new GeometryShader(head+create_source(*i)));
+			program.attach_shader_owned(new GeometryShader(apply<Formatter>(*i)));
 		else if(i->type==FRAGMENT)
-			program.attach_shader_owned(new FragmentShader(head+create_source(*i)));
+		{
+			program.attach_shader_owned(new FragmentShader(apply<Formatter>(*i)));
+			if(EXT_gpu_shader4)
+			{
+				for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
+					program.bind_fragment_data(j->second, j->first);
+			}
+		}
+	}
+}
+
+Module *ProgramCompiler::create_builtins_module()
+{
+	ProgramParser parser;
+	Module *module = new Module(parser.parse(builtins_src, "<builtin>"));
+	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::append_module(ProgramSyntax::Module &mod)
+{
+	vector<Import *> imports = apply<NodeGatherer<Import> >(mod.shared);
+	for(vector<Import *>::iterator i=imports.begin(); i!=imports.end(); ++i)
+		import((*i)->module);
+	apply<NodeRemover>(mod.shared, set<Node *>(imports.begin(), imports.end()));
+
+	append_stage(mod.shared);
+	for(list<Stage>::iterator i=mod.stages.begin(); i!=mod.stages.end(); ++i)
+		append_stage(*i);
+}
+
+void ProgramCompiler::append_stage(Stage &stage)
+{
+	Stage *target = 0;
+	if(stage.type==SHARED)
+		target = &module->shared;
+	else
+	{
+		list<Stage>::iterator i;
+		for(i=module->stages.begin(); (i!=module->stages.end() && i->type<stage.type); ++i) ;
+		if(i==module->stages.end() || i->type>stage.type)
+		{
+			list<Stage>::iterator j = module->stages.insert(i, stage.type);
+			if(i!=module->stages.end())
+				i->previous = &*j;
+			i = j;
+			if(i!=module->stages.begin())
+				i->previous = &*--j;
+		}
+
+		target = &*i;
 	}
 
-	program.bind_attribute(VERTEX4, "vertex");
-	program.bind_attribute(NORMAL3, "normal");
-	program.bind_attribute(COLOR4_FLOAT, "color");
-	program.bind_attribute(TEXCOORD4, "texcoord");
+	for(NodeList<Node>::iterator i=stage.content.body.begin(); i!=stage.content.body.end(); ++i)
+		target->content.body.push_back(*i);
+	apply<DeclarationCombiner>(*target);
 }
 
 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;
+	}
 	for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
-		optimize(*i);
+		finalize(*i);
+}
+
+void ProgramCompiler::import(const string &name)
+{
+	string fn = name+".glsl";
+	if(imported_names.count(fn))
+		return;
+	imported_names.insert(fn);
+
+	RefPtr<IO::Seekable> io = (resources ? resources->open_raw(fn) : Resources::get_builtins().open(fn));
+	if(!io)
+		throw runtime_error(format("module %s not found", name));
+	ProgramParser import_parser;
+	append_module(import_parser.parse(*io, fn));
 }
 
 void ProgramCompiler::generate(Stage &stage)
 {
 	inject_block(stage.content, module->shared.content);
 
+	apply<DeclarationReorderer>(stage);
+	apply<FunctionResolver>(stage);
 	apply<VariableResolver>(stage);
 	apply<InterfaceGenerator>(stage);
 	apply<VariableResolver>(stage);
-	apply<VariableRenamer>(stage);
+	apply<DeclarationReorderer>(stage);
+	apply<FunctionResolver>(stage);
+	apply<LegacyConverter>(stage);
 }
 
-void ProgramCompiler::optimize(Stage &stage)
+bool ProgramCompiler::optimize(Stage &stage)
 {
-	while(1)
-	{
-		UnusedVariableLocator unused_locator;
-		unused_locator.apply(stage);
+	apply<ConstantConditionEliminator>(stage);
 
-		NodeRemover remover;
-		remover.to_remove = unused_locator.unused_nodes;
-		remover.apply(stage);
+	set<FunctionDeclaration *> inlineable = apply<InlineableFunctionLocator>(stage);
+	apply<FunctionInliner>(stage, inlineable);
 
-		if(!remover.n_removed)
-			break;
-	}
+	set<Node *> unused = apply<UnusedVariableLocator>(stage);
+	set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
+	unused.insert(unused2.begin(), unused2.end());
+	apply<NodeRemover>(stage, unused);
+
+	return !unused.empty();
+}
+
+void ProgramCompiler::finalize(Stage &stage)
+{
+	if(get_gl_api()==OPENGL_ES2)
+		apply<DefaultPrecisionGenerator>(stage);
+	else
+		apply<PrecisionRemover>(stage);
 }
 
 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)
+	list<RefPtr<Node> >::iterator insert_point = target.body.begin();
+	for(list<RefPtr<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)
+typename T::ResultType ProgramCompiler::apply(Stage &stage)
 {
 	T visitor;
 	visitor.apply(stage);
+	return visitor.get_result();
 }
 
-string ProgramCompiler::create_source(Stage &stage)
+template<typename T, typename A>
+typename T::ResultType ProgramCompiler::apply(Stage &stage, const A &arg)
 {
-	Formatter formatter;
-	formatter.apply(stage);
-	return formatter.formatted;
+	T visitor(arg);
+	visitor.apply(stage);
+	return visitor.get_result();
 }
 
 
@@ -118,12 +270,60 @@ void ProgramCompiler::Visitor::apply(Stage &s)
 }
 
 
+ProgramCompiler::BlockModifier::BlockModifier():
+	remove_node(false)
+{ }
+
+void ProgramCompiler::BlockModifier::flatten_block(Block &block)
+{
+	insert_nodes.insert(insert_nodes.end(), block.body.begin(), block.body.end());
+	remove_node = true;
+}
+
+void ProgramCompiler::BlockModifier::apply_and_increment(Block &block, list<RefPtr<Node> >::iterator &i)
+{
+	block.body.insert(i, insert_nodes.begin(), insert_nodes.end());
+	insert_nodes.clear();
+
+	if(remove_node)
+		block.body.erase(i++);
+	else
+		++i;
+	remove_node = false;
+}
+
+void ProgramCompiler::BlockModifier::visit(Block &block)
+{
+	for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+	{
+		(*i)->visit(*this);
+		apply_and_increment(block, i);
+	}
+}
+
+
 ProgramCompiler::Formatter::Formatter():
 	indent(0),
 	parameter_list(false),
-	else_if(false)
+	else_if(0)
 { }
 
+void ProgramCompiler::Formatter::apply(ProgramSyntax::Stage &s)
+{
+	GLApi api = get_gl_api();
+	const Version &ver = s.required_version;
+
+	if(ver)
+	{
+		formatted += format("#version %d%02d", ver.major, ver.minor);
+		if(api==OPENGL_ES2 && ver>=Version(3, 0))
+			formatted += " es";
+		formatted += '\n';
+	}
+
+	Visitor::apply(s);
+}
+
 void ProgramCompiler::Formatter::visit(Literal &literal)
 {
 	formatted += literal.token;
@@ -159,18 +359,22 @@ void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
 {
 	binary.left->visit(*this);
-	if(binary.assignment)
-		formatted += format(" %s ", binary.oper);
-	else
-		formatted += binary.oper;
+	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)
 {
 	formatted += format("%s(", call.name);
-	for(vector<NodePtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
+	for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 	{
 		if(i!=call.arguments.begin())
 			formatted += ", ";
@@ -187,31 +391,37 @@ void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
 
 void ProgramCompiler::Formatter::visit(Block &block)
 {
-	if(block.use_braces)
-	{
-		if(else_if)
-		{
-			formatted += '\n';
-			else_if = false;
-		}
-		formatted += format("%s{\n", string(indent*2, ' '));
-	}
+	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+(indent>0 || use_braces));
 	string spaces(indent*2, ' ');
-	for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
+	for(list<RefPtr<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(Import &import)
+{
+	formatted += format("import %s;", import.module);
+}
+
+void ProgramCompiler::Formatter::visit(Precision &prec)
+{
+	formatted += format("precision %s %s;", prec.precision, prec.type);
 }
 
 void ProgramCompiler::Formatter::visit(Layout &layout)
@@ -225,7 +435,13 @@ void ProgramCompiler::Formatter::visit(Layout &layout)
 		if(!i->value.empty())
 			formatted += format("=%s", i->value);
 	}
-	formatted += format(") %s;", layout.interface);
+	formatted += ')';
+}
+
+void ProgramCompiler::Formatter::visit(InterfaceLayout &layout)
+{
+	layout.layout.visit(*this);
+	formatted += format(" %s;", layout.interface);
 }
 
 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
@@ -237,12 +453,29 @@ void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
 
 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 {
+	if(var.layout)
+	{
+		var.layout->visit(*this);
+		formatted += ' ';
+	}
 	if(var.constant)
 		formatted += "const ";
 	if(!var.sampling.empty())
 		formatted += format("%s ", var.sampling);
-	if(!var.interface.empty())
-		formatted += format("%s ", var.interface);
+	if(!var.interface.empty() && var.interface!=block_interface)
+	{
+		string interface = var.interface;
+		if(stage->required_version<Version(1, 30))
+		{
+			if(stage->type==VERTEX && var.interface=="in")
+				interface = "attribute";
+			else if((stage->type==VERTEX && var.interface=="out") || (stage->type==FRAGMENT && var.interface=="in"))
+				interface = "varying";
+		}
+		formatted += format("%s ", interface);
+	}
+	if(!var.precision.empty())
+		formatted += format("%s ", var.precision);
 	formatted += format("%s %s", var.type, var.name);
 	if(var.array)
 	{
@@ -262,6 +495,7 @@ void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 
 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 += ';';
@@ -270,7 +504,7 @@ void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 {
 	formatted += format("%s %s(", func.return_type, func.name);
-	for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
+	for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 	{
 		if(i!=func.parameters.begin())
 			formatted += ", ";
@@ -278,7 +512,7 @@ void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 		(*i)->visit(*this);
 	}
 	formatted += ')';
-	if(func.definition)
+	if(func.definition==&func)
 	{
 		formatted += '\n';
 		func.body.visit(*this);
@@ -290,10 +524,9 @@ void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 void ProgramCompiler::Formatter::visit(Conditional &cond)
 {
 	if(else_if)
-	{
-		formatted += ' ';
-		else_if = false;
-	}
+		formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
+
+	indent -= else_if;
 
 	formatted += "if(";
 	cond.condition->visit(*this);
@@ -302,8 +535,8 @@ void ProgramCompiler::Formatter::visit(Conditional &cond)
 	cond.body.visit(*this);
 	if(!cond.else_body.body.empty())
 	{
-		formatted += format("\n%selse", string(indent*2, ' '));
-		SetFlag set(else_if);
+		formatted += format("\n%selse\n", string(indent*2, ' '));
+		SetForScope<unsigned> set(else_if, 2);
 		cond.else_body.visit(*this);
 	}
 }
@@ -327,11 +560,73 @@ void ProgramCompiler::Formatter::visit(Return &ret)
 	formatted += ';';
 }
 
+void ProgramCompiler::Formatter::visit(Jump &jump)
+{
+	formatted += jump.keyword;
+	formatted += ';';
+}
+
+
+ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
+	toplevel(true)
+{ }
+
+void ProgramCompiler::DeclarationCombiner::visit(Block &block)
+{
+	if(!toplevel)
+		return;
+
+	SetForScope<bool> set(toplevel, false);
+	BlockModifier::visit(block);
+}
+
+void ProgramCompiler::DeclarationCombiner::visit(FunctionDeclaration &func)
+{
+	vector<FunctionDeclaration *> &decls = functions[func.name];
+	if(func.definition)
+	{
+		for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
+		{
+			(*i)->definition = func.definition;
+			(*i)->body.body.clear();
+		}
+	}
+	decls.push_back(&func);
+}
+
+void ProgramCompiler::DeclarationCombiner::visit(VariableDeclaration &var)
+{
+	VariableDeclaration *&ptr = variables[var.name];
+	if(ptr)
+	{
+		ptr->type = var.type;
+		if(var.init_expression)
+			ptr->init_expression = var.init_expression;
+		remove_node = true;
+	}
+	else
+		ptr = &var;
+}
+
 
 ProgramCompiler::VariableResolver::VariableResolver():
-	anonymous(false)
+	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);
@@ -355,6 +650,19 @@ void ProgramCompiler::VariableResolver::visit(VariableReference &var)
 			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)
@@ -379,7 +687,10 @@ void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 {
 	if(binary.oper=="[")
 	{
-		binary.right->visit(*this);
+		{
+			SetForScope<bool> set(record_target, false);
+			binary.right->visit(*this);
+		}
 		type = 0;
 		binary.left->visit(*this);
 	}
@@ -390,6 +701,21 @@ void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 	}
 }
 
+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);
@@ -406,6 +732,9 @@ void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 			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)
@@ -415,13 +744,41 @@ void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
 {
 	SetFlag set(anonymous);
+	SetForScope<string> set2(block_interface, iface.interface);
 	TraversingVisitor::visit(iface);
 }
 
 
+void ProgramCompiler::FunctionResolver::visit(FunctionCall &call)
+{
+	map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
+	if(i!=functions.end())
+		call.declaration = i->second.back();
+
+	TraversingVisitor::visit(call);
+}
+
+void ProgramCompiler::FunctionResolver::visit(FunctionDeclaration &func)
+{
+	vector<FunctionDeclaration *> &decls = functions[func.name];
+	if(func.definition)
+	{
+		for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
+			(*i)->definition = func.definition;
+		decls.clear();
+		decls.push_back(&func);
+	}
+	else if(!decls.empty() && decls.back()->definition)
+		func.definition = decls.back()->definition;
+	else
+		decls.push_back(&func);
+
+	TraversingVisitor::visit(func);
+}
+
+
 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
-	scope_level(0),
-	remove_node(false)
+	scope_level(0)
 { }
 
 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
@@ -446,29 +803,21 @@ void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
 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(); )
+	for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 	{
 		(*i)->visit(*this);
 
 		if(scope_level==1)
 		{
-			for(map<string, Node *>::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
+			for(map<string, RefPtr<VariableDeclaration> >::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
 			{
-				list<NodePtr<Node> >::iterator k = block.body.insert(i, j->second);
+				list<RefPtr<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;
+		apply_and_increment(block, i);
 	}
 }
 
@@ -478,22 +827,26 @@ string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, co
 	return prefix+name.substr(offset);
 }
 
-bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &out, const string &iface, const string &name)
+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 = out.sampling;
+	iface_var->sampling = var.sampling;
 	iface_var->interface = iface;
-	iface_var->type = out.type;
-	iface_var->type_declaration = out.type_declaration;
+	iface_var->type = var.type;
+	iface_var->type_declaration = var.type_declaration;
 	iface_var->name = name;
-	iface_var->array = (out.array || (stage->type==GEOMETRY && iface=="in"));
-	iface_var->array_size = out.array_size;
+	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 = &out;
+		iface_var->linked_declaration = &var;
 	iface_declarations[name] = iface_var;
 
 	return true;
@@ -501,16 +854,16 @@ bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration
 
 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
 {
-	BinaryExpression *assign = new BinaryExpression;
+	Assignment *assign = new Assignment;
 	VariableReference *ref = new VariableReference;
 	ref->name = left;
 	assign->left = ref;
 	assign->oper = "=";
 	assign->right = right;
-	assign->assignment = true;
 
 	ExpressionStatement *stmt = new ExpressionStatement;
 	stmt->expression = assign;
+	stmt->visit(*this);
 	insert_nodes.push_back(stmt);
 }
 
@@ -526,7 +879,10 @@ void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
 	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);
+	{
+		generate_interface(*i->second, "in", i->second->name);
+		var.name = i->second->name;
+	}
 }
 
 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
@@ -539,7 +895,10 @@ void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
 		{
 			remove_node = true;
 			if(var.init_expression)
+			{
 				insert_assignment(var.name, var.init_expression->clone());
+				return;
+			}
 		}
 	}
 	else if(var.interface=="in")
@@ -564,161 +923,902 @@ void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &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, RefPtr<VariableDeclaration> >::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
+		if(i->second->interface=="in")
+			pass_vars.push_back(i->second.get());
+
 	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)
 		{
-			string out_name = change_prefix(i->second->name, out_prefix);
-			generate_interface(*i->second, "in", i->second->name);
-			generate_interface(*i->second, "out", out_name);
+			bool linked = false;
+			for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
+				linked = ((*j)->linked_declaration==i->second);
 
-			VariableReference *ref = new VariableReference;
-			ref->name = i->first;
-			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);
+			if(!linked && generate_interface(*i->second, "in", i->second->name))
+				pass_vars.push_back(i->second);
 		}
 	}
 
-	remove_node = true;
-}
-
-
-void ProgramCompiler::VariableRenamer::visit(VariableReference &var)
-{
-	if(var.declaration)
-		var.name = var.declaration->name;
-}
+	if(stage->type==GEOMETRY)
+	{
+		VariableReference *ref = new VariableReference;
+		ref->name = "gl_in";
 
-void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
-{
-	if(var.linked_declaration)
-		var.name = var.linked_declaration->name;
-	TraversingVisitor::visit(var);
-}
+		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";
 
-ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
-	assignment(false),
-	assignment_target(0)
-{ }
+		insert_assignment("gl_Position", memacc);
+	}
 
-void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
-{
-	if(assignment)
-		assignment_target = var.declaration;
-	else
+	for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 	{
-		unused_nodes.erase(var.declaration);
-		map<VariableDeclaration *, Node *>::iterator i = assignments.find(var.declaration);
-		if(i!=assignments.end())
+		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)
 		{
-			unused_nodes.erase(i->second);
-			assignments.erase(i);
+			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);
 	}
-}
 
-void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
-{
-	TraversingVisitor::visit(memacc);
-	unused_nodes.erase(memacc.declaration);
+	remove_node = true;
 }
 
-void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
-{
-	if(binary.assignment)
-	{
-		binary.right->visit(*this);
-		assignment = true;
-		binary.left->visit(*this);
-	}
-	else
-		TraversingVisitor::visit(binary);
-}
 
-void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
-{
-	assignment = false;
-	assignment_target = 0;
-	TraversingVisitor::visit(expr);
-	if(assignment && assignment_target)
-	{
-		Node *&assign = assignments[assignment_target];
-		if(assign)
-			unused_nodes.insert(assign);
-		assign = &expr;
-		if(assignment_target->interface!="out" || (stage->type!=FRAGMENT && !assignment_target->linked_declaration))
-			unused_nodes.insert(&expr);
-		else
-			unused_nodes.erase(assignment_target);
-	}
-	assignment = false;
-}
+ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
+	scope_level(0),
+	kind(NO_DECLARATION)
+{ }
 
-void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
+void ProgramCompiler::DeclarationReorderer::visit(FunctionCall &call)
 {
-	unused_nodes.insert(&var);
-	TraversingVisitor::visit(var);
+	FunctionDeclaration *def = call.declaration;
+	if(def)
+		def = def->definition;
+	if(def && !ordered_funcs.count(def))
+		needed_funcs.insert(def);
 }
 
+void ProgramCompiler::DeclarationReorderer::visit(Block &block)
+{
+	SetForScope<unsigned> set(scope_level, scope_level+1);
+	if(scope_level>1)
+		return Visitor::visit(block);
 
-ProgramCompiler::NodeRemover::NodeRemover():
-	n_removed(0),
-	immutable_block(false),
-	remove_block(false)
-{ }
+	list<RefPtr<Node> >::iterator struct_insert_point = block.body.end();
+	list<RefPtr<Node> >::iterator variable_insert_point = block.body.end();
+	list<RefPtr<Node> >::iterator function_insert_point = block.body.end();
+	unsigned unordered_func_count = 0;
+	bool ordered_any_funcs = false;
 
-void ProgramCompiler::NodeRemover::visit(Block &block)
-{
-	remove_block = immutable_block;
-	for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+	for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 	{
-		bool remove = to_remove.count(&**i);
-		if(!remove)
-			remove_block = false;
+		kind = NO_DECLARATION;
 		(*i)->visit(*this);
 
-		if(remove ? !immutable_block : remove_block)
+		bool moved = false;
+		if(kind==STRUCT && struct_insert_point!=block.body.end())
+		{
+			block.body.insert(struct_insert_point, *i);
+			moved = true;
+		}
+		else if(kind>STRUCT && struct_insert_point==block.body.end())
+			struct_insert_point = i;
+
+		if(kind==VARIABLE && variable_insert_point!=block.body.end())
+		{
+			block.body.insert(variable_insert_point, *i);
+			moved = true;
+		}
+		else if(kind>VARIABLE && variable_insert_point==block.body.end())
+			variable_insert_point = i;
+
+		if(kind==FUNCTION)
+		{
+			if(function_insert_point==block.body.end())
+				function_insert_point = i;
+
+			if(needed_funcs.empty())
+			{
+				ordered_funcs.insert(i->get());
+				if(i!=function_insert_point)
+				{
+					block.body.insert(function_insert_point, *i);
+					moved = true;
+				}
+				else
+					++function_insert_point;
+				ordered_any_funcs = true;
+			}
+			else
+				++unordered_func_count;
+		}
+
+		if(moved)
 		{
+			if(function_insert_point==i)
+				++function_insert_point;
 			block.body.erase(i++);
-			++n_removed;
 		}
 		else
 			++i;
+
+		if(i==block.body.end() && unordered_func_count)
+		{
+			if(!ordered_any_funcs)
+				// A subset of the remaining functions forms a recursive loop
+				/* TODO pick a function and move it up, adding any necessary
+				declarations */
+				break;
+
+			i = function_insert_point;
+			unordered_func_count = 0;
+		}
+	}
+}
+
+void ProgramCompiler::DeclarationReorderer::visit(ProgramSyntax::VariableDeclaration &var)
+{
+	Visitor::visit(var);
+	kind = VARIABLE;
+}
+
+void ProgramCompiler::DeclarationReorderer::visit(FunctionDeclaration &func)
+{
+	needed_funcs.clear();
+	func.body.visit(*this);
+	needed_funcs.erase(&func);
+	kind = FUNCTION;
+}
+
+
+ProgramCompiler::InlineableFunctionLocator::InlineableFunctionLocator():
+	in_function(0)
+{ }
+
+void ProgramCompiler::InlineableFunctionLocator::visit(FunctionCall &call)
+{
+	FunctionDeclaration *def = call.declaration;
+	if(def && def->definition!=def)
+		def = def->definition;
+
+	if(def)
+	{
+		unsigned &count = refcounts[def];
+		++count;
+		if(count>1 || def==in_function)
+			inlineable.erase(def);
+	}
+
+	TraversingVisitor::visit(call);
+}
+
+void ProgramCompiler::InlineableFunctionLocator::visit(FunctionDeclaration &func)
+{
+	unsigned &count = refcounts[func.definition];
+	if(!count && func.parameters.empty())
+		inlineable.insert(func.definition);
+
+	SetForScope<FunctionDeclaration *> set(in_function, &func);
+	TraversingVisitor::visit(func);
+}
+
+
+ProgramCompiler::FunctionInliner::FunctionInliner():
+	extract_result(0)
+{ }
+
+ProgramCompiler::FunctionInliner::FunctionInliner(const set<FunctionDeclaration *> &in):
+	inlineable(in),
+	extract_result(0)
+{ }
+
+void ProgramCompiler::FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
+{
+	inline_result = 0;
+	ptr->visit(*this);
+	if(inline_result)
+		ptr = inline_result;
+}
+
+void ProgramCompiler::FunctionInliner::visit(Block &block)
+{
+	if(extract_result)
+		--extract_result;
+
+	for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
+	{
+		(*i)->visit(*this);
+		if(extract_result)
+			--extract_result;
+	}
+}
+
+void ProgramCompiler::FunctionInliner::visit(UnaryExpression &unary)
+{
+	visit_and_inline(unary.expression);
+	inline_result = 0;
+}
+
+void ProgramCompiler::FunctionInliner::visit(BinaryExpression &binary)
+{
+	visit_and_inline(binary.left);
+	visit_and_inline(binary.right);
+	inline_result = 0;
+}
+
+void ProgramCompiler::FunctionInliner::visit(FunctionCall &call)
+{
+	for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
+		visit_and_inline(*i);
+
+	FunctionDeclaration *def = call.declaration;
+	if(def && def->definition!=def)
+		def = def->definition;
+
+	if(def && inlineable.count(def))
+	{
+		extract_result = 2;
+		def->visit(*this);
+	}
+	else
+		inline_result = 0;
+}
+
+void ProgramCompiler::FunctionInliner::visit(Return &ret)
+{
+	TraversingVisitor::visit(ret);
+
+	if(extract_result)
+		inline_result = ret.expression->clone();
+}
+
+
+ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
+	variable_values(0),
+	result(0.0f),
+	result_valid(false)
+{ }
+
+ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator(const ValueMap &v):
+	variable_values(&v),
+	result(0.0f),
+	result_valid(false)
+{ }
+
+void ProgramCompiler::ExpressionEvaluator::visit(Literal &literal)
+{
+	if(literal.token=="true")
+		result = 1.0f;
+	else if(literal.token=="false")
+		result = 0.0f;
+	else
+		result = lexical_cast<float>(literal.token);
+	result_valid = true;
+}
+
+void ProgramCompiler::ExpressionEvaluator::visit(ParenthesizedExpression &parexp)
+{
+	parexp.expression->visit(*this);
+}
+
+void ProgramCompiler::ExpressionEvaluator::visit(VariableReference &var)
+{
+	if(!var.declaration)
+		return;
+
+	if(variable_values)
+	{
+		ValueMap::const_iterator i = variable_values->find(var.declaration);
+		if(i!=variable_values->end())
+			i->second->visit(*this);
+	}
+	else if(var.declaration->init_expression)
+		var.declaration->init_expression->visit(*this);
+}
+
+void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
+{
+	result_valid = false;
+	unary.expression->visit(*this);
+	if(!result_valid)
+		return;
+
+	if(unary.oper=="!")
+		result = !result;
+	else
+		result_valid = false;
+}
+
+void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
+{
+	result_valid = false;
+	binary.left->visit(*this);
+	if(!result_valid)
+		return;
+
+	float left_result = result;
+	result_valid = false;
+	binary.right->visit(*this);
+	if(!result_valid)
+		return;
+
+	if(binary.oper=="<")
+		result = (left_result<result);
+	else if(binary.oper=="<=")
+		result = (left_result<=result);
+	else if(binary.oper==">")
+		result = (left_result>result);
+	else if(binary.oper==">=")
+		result = (left_result>=result);
+	else if(binary.oper=="==")
+		result = (left_result==result);
+	else if(binary.oper=="!=")
+		result = (left_result!=result);
+	else if(binary.oper=="&&")
+		result = (left_result && result);
+	else if(binary.oper=="||")
+		result = (left_result || result);
+	else
+		result_valid = false;
+}
+
+
+ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
+	scope_level(0)
+{ }
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
+{
+	SetForScope<unsigned> set(scope_level, scope_level+1);
+	BlockModifier::visit(block);
+
+	for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
+		variable_values.erase(i->second);
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
+{
+	variable_values.erase(assign.target_declaration);
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
+{
+	if(var.constant || scope_level>1)
+		variable_values[&var] = var.init_expression.get();
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
+{
+	ExpressionEvaluator eval(variable_values);
+	cond.condition->visit(eval);
+	if(eval.result_valid)
+		flatten_block(eval.result ? cond.body : cond.else_body);
+	else
+		TraversingVisitor::visit(cond);
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
+{
+	if(iter.condition)
+	{
+		ExpressionEvaluator eval;
+		iter.condition->visit(eval);
+		if(eval.result_valid && !eval.result)
+		{
+			remove_node = true;
+			return;
+		}
+	}
+
+	TraversingVisitor::visit(iter);
+}
+
+
+ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
+	aggregate(0),
+	assignment(0),
+	assignment_target(false),
+	global_scope(true)
+{ }
+
+void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
+{
+	variables.push_back(BlockVariableMap());
+	Visitor::apply(s);
+	BlockVariableMap &global_variables = variables.back();
+	for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
+	{
+		if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
+			continue;
+		if(!i->second.referenced)
+		{
+			unused_nodes.insert(i->first);
+			clear_assignments(i->second, true);
+		}
 	}
+	variables.pop_back();
 }
 
-void ProgramCompiler::NodeRemover::visit(StructDeclaration &strct)
+void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
 {
-	SetFlag set(immutable_block);
+	map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
+	if(i!=aggregates.end())
+		unused_nodes.erase(i->second);
+
+	if(var.declaration && !assignment_target)
+	{
+		VariableInfo &var_info = variables.back()[var.declaration];
+		var_info.assignments.clear();
+		var_info.referenced = true;
+	}
+}
+
+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)
+{
+	VariableInfo &var_info = variables.back()[&var];
+	if(!self_ref)
+		clear_assignments(var_info, true);
+	var_info.assignments.push_back(&node);
+	var_info.conditionally_assigned = false;
+}
+
+void ProgramCompiler::UnusedVariableLocator::clear_assignments(VariableInfo &var_info, bool mark_unused)
+{
+	if(mark_unused)
+	{
+		for(vector<Node *>::iterator i=var_info.assignments.begin(); i!=var_info.assignments.end(); ++i)
+			unused_nodes.insert(*i);
+	}
+	var_info.assignments.clear();
+}
+
+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
+	{
+		variables.back()[&var].local = true;
+		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)
+{
+	variables.push_back(BlockVariableMap());
+
+	{
+		SetForScope<bool> set(global_scope, false);
+		for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
+			(*i)->visit(*this);
+		func.body.visit(*this);
+	}
+
+	BlockVariableMap &block_variables = variables.back();
+	for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
+		i->second.conditionally_assigned = true;
+	for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
+		block_variables[i->get()].referenced = true;
+	merge_down_variables();
+}
+
+void ProgramCompiler::UnusedVariableLocator::merge_down_variables()
+{
+	BlockVariableMap &parent_variables = variables[variables.size()-2];
+	BlockVariableMap &block_variables = variables.back();
+	for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
+	{
+		if(i->second.local)
+		{
+			if(!i->second.referenced)
+				unused_nodes.insert(i->first);
+			clear_assignments(i->second, true);
+			continue;
+		}
+
+		BlockVariableMap::iterator j = parent_variables.find(i->first);
+		if(j==parent_variables.end())
+			parent_variables.insert(*i);
+		else
+		{
+			if(i->second.referenced || !i->second.conditionally_assigned)
+				clear_assignments(j->second, !i->second.referenced);
+			j->second.conditionally_assigned = i->second.conditionally_assigned;
+			j->second.referenced |= i->second.referenced;
+			j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin(), i->second.assignments.end());
+		}
+	}
+	variables.pop_back();
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
+{
+	cond.condition->visit(*this);
+	variables.push_back(BlockVariableMap());
+	cond.body.visit(*this);
+
+	BlockVariableMap if_variables;
+	swap(variables.back(), if_variables);
+	cond.else_body.visit(*this);
+
+	BlockVariableMap &else_variables = variables.back();
+	for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
+	{
+		BlockVariableMap::iterator j = if_variables.find(i->first);
+		if(j!=if_variables.end())
+		{
+			i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
+			i->second.conditionally_assigned |= j->second.conditionally_assigned;
+			if_variables.erase(j);
+		}
+		else
+			i->second.conditionally_assigned = true;
+	}
+
+	for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
+	{
+		i->second.conditionally_assigned = true;
+		else_variables.insert(*i);
+	}
+
+	merge_down_variables();
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
+{
+	variables.push_back(BlockVariableMap());
+	TraversingVisitor::visit(iter);
+
+	BlockVariableMap &block_variables = variables.back();
+	for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
+		if(!i->second.local && i->second.referenced)
+			i->second.assignments.clear();
+
+	merge_down_variables();
+}
+
+
+ProgramCompiler::UnusedVariableLocator::VariableInfo::VariableInfo():
+	local(false),
+	conditionally_assigned(false),
+	referenced(false)
+{ }
+
+
+void ProgramCompiler::UnusedFunctionLocator::visit(FunctionCall &call)
+{
+	TraversingVisitor::visit(call);
+
+	unused_nodes.erase(call.declaration);
+	if(call.declaration && call.declaration->definition!=call.declaration)
+		used_definitions.insert(call.declaration->definition);
+}
+
+void ProgramCompiler::UnusedFunctionLocator::visit(FunctionDeclaration &func)
+{
+	TraversingVisitor::visit(func);
+
+	if((func.name!="main" || func.body.body.empty()) && !used_definitions.count(&func))
+		unused_nodes.insert(&func);
+}
+
+
+ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
+	to_remove(r)
+{ }
+
+void ProgramCompiler::NodeRemover::visit(Block &block)
+{
+	for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+	{
+		(*i)->visit(*this);
+		if(to_remove.count(i->get()))
+			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);
+		stage->locations.erase(var.name);
 		if(var.linked_declaration)
 			var.linked_declaration->linked_declaration = 0;
 	}
+	else if(var.init_expression && to_remove.count(var.init_expression.get()))
+		var.init_expression = 0;
 }
 
-void ProgramCompiler::NodeRemover::visit(InterfaceBlock &iface)
+
+void ProgramCompiler::PrecisionRemover::visit(Precision &)
 {
-	SetFlag set(immutable_block);
-	TraversingVisitor::visit(iface);
+	remove_node = true;
+}
+
+void ProgramCompiler::PrecisionRemover::visit(VariableDeclaration &var)
+{
+	var.precision.clear();
+}
+
+
+ProgramCompiler::DefaultPrecisionGenerator::DefaultPrecisionGenerator():
+	toplevel(true)
+{ }
+
+void ProgramCompiler::DefaultPrecisionGenerator::visit(Block &block)
+{
+	if(toplevel)
+	{
+		SetForScope<bool> set(toplevel, false);
+		BlockModifier::visit(block);
+	}
+	else
+		Visitor::visit(block);
+}
+
+void ProgramCompiler::DefaultPrecisionGenerator::visit(Precision &prec)
+{
+	have_default.insert(prec.type);
+}
+
+void ProgramCompiler::DefaultPrecisionGenerator::visit(VariableDeclaration &var)
+{
+	if(var.type_declaration)
+		return;
+
+	string type = var.type;
+	if(!type.compare(0, 3, "vec") || !type.compare(0, 3, "mat"))
+		type = "float";
+	else if(!type.compare(0, 3, "ivec") || type=="uint")
+		type = "int";
+
+	if(!have_default.count(type))
+	{
+		Precision *prec = new Precision;
+		if(!type.compare(0, 7, "sampler"))
+			prec->precision = "lowp";
+		else if(stage->type==FRAGMENT)
+			prec->precision = "mediump";
+		else
+			prec->precision = "highp";
+		prec->type = type;
+		insert_nodes.push_back(prec);
+
+		have_default.insert(type);
+	}
+}
+
+
+ProgramCompiler::LegacyConverter::LegacyConverter():
+	target_api(get_gl_api()),
+	target_version(get_glsl_version()),
+	frag_out(0)
+{ }
+
+ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
+	target_api(get_gl_api()),
+	target_version(v),
+	frag_out(0)
+{ }
+
+bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version) const
+{
+	if(target_version<feature_version)
+		return false;
+	else if(stage->required_version<feature_version)
+		stage->required_version = feature_version;
+
+	return true;
+}
+
+bool ProgramCompiler::LegacyConverter::supports_unified_interface_syntax() const
+{
+	if(target_api==OPENGL_ES2)
+		return check_version(Version(3, 0));
+	else
+		return check_version(Version(1, 30));
+}
+
+void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
+{
+	if(var.declaration==frag_out && !supports_unified_interface_syntax())
+	{
+		var.name = "gl_FragColor";
+		var.declaration = 0;
+		type = "vec4";
+	}
+	else if(var.declaration)
+		type = var.declaration->type;
+	else
+		type = string();
+}
+
+void ProgramCompiler::LegacyConverter::visit(Assignment &assign)
+{
+	TraversingVisitor::visit(assign);
+	if(assign.target_declaration==frag_out && !supports_unified_interface_syntax())
+		assign.target_declaration = 0;
+}
+
+bool ProgramCompiler::LegacyConverter::supports_unified_sampling_functions() const
+{
+	if(target_api==OPENGL_ES2)
+		return check_version(Version(3, 0));
+	else
+		return check_version(Version(1, 30));
+}
+
+void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
+{
+	if(call.name=="texture" && !call.declaration && !supports_unified_sampling_functions())
+	{
+		vector<RefPtr<Expression> >::iterator i = call.arguments.begin();
+		if(i!=call.arguments.end())
+		{
+			(*i)->visit(*this);
+			if(type=="sampler1D")
+				call.name = "texture1D";
+			else if(type=="sampler2D")
+				call.name = "texture2D";
+			else if(type=="sampler3D")
+				call.name = "texture3D";
+			else if(type=="sampler1DShadow")
+				call.name = "shadow1D";
+			else if(type=="sampler2DShadow")
+				call.name = "shadow2D";
+
+			for(; i!=call.arguments.end(); ++i)
+				(*i)->visit(*this);
+		}
+	}
+	else
+		TraversingVisitor::visit(call);
+}
+
+bool ProgramCompiler::LegacyConverter::supports_interface_layouts() const
+{
+	if(target_api==OPENGL_ES2)
+		return check_version(Version(3, 0));
+	else
+		return check_version(Version(3, 30));
+}
+
+void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
+{
+	if(var.layout && !supports_interface_layouts())
+	{
+		vector<Layout::Qualifier>::iterator i;
+		for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->identifier!="location"); ++i) ;
+		if(i!=var.layout->qualifiers.end())
+		{
+			unsigned location = lexical_cast<unsigned>(i->value);
+			if(stage->type==VERTEX && var.interface=="in")
+			{
+				stage->locations[var.name] = location;
+				var.layout->qualifiers.erase(i);
+			}
+			else if(stage->type==FRAGMENT && var.interface=="out")
+			{
+				if(location!=0)
+					static Require _req(EXT_gpu_shader4);
+				stage->locations[var.name] = location;
+				var.layout->qualifiers.erase(i);
+			}
+
+			if(var.layout->qualifiers.empty())
+				var.layout = 0;
+		}
+	}
+
+	if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
+	{
+		if(stage->type==FRAGMENT && var.interface=="out")
+		{
+			frag_out = &var;
+			remove_node = true;
+		}
+	}
+
+	TraversingVisitor::visit(var);
+}
+
+bool ProgramCompiler::LegacyConverter::supports_interface_blocks(const string &iface) const
+{
+	if(target_api==OPENGL_ES2)
+	{
+		if(iface=="uniform")
+			return check_version(Version(3, 0));
+		else
+			return check_version(Version(3, 20));
+	}
+	else
+		return check_version(Version(1, 50));
+}
+
+void ProgramCompiler::LegacyConverter::visit(InterfaceBlock &iface)
+{
+	if(!supports_interface_blocks(iface.interface))
+		flatten_block(iface.members);
 }
 
 } // namespace GL