X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=blobdiff_plain;f=source%2Fprogramcompiler.cpp;h=9b3266755b0b4f36c7bdc1ebe3471ebba48e8d40;hp=934416c28684f250fa8c37b9d842f5f05c39b7a9;hb=ba97b71564cadd322fe1bf3d8afe556b38ef0647;hpb=96881e56ececfa3f4b0707dc168c687b35d249a0

diff --git a/source/programcompiler.cpp b/source/programcompiler.cpp
index 934416c2..9b326675 100644
--- a/source/programcompiler.cpp
+++ b/source/programcompiler.cpp
@@ -4,27 +4,51 @@
 #include "error.h"
 #include "program.h"
 #include "programcompiler.h"
+#include "resources.h"
 #include "shader.h"
 
 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 {
 
 using namespace ProgramSyntax;
 
 ProgramCompiler::ProgramCompiler():
+	resources(0),
 	module(0)
 { }
 
 void ProgramCompiler::compile(const string &source)
 {
+	resources = 0;
 	module = &parser.parse(source);
 	process();
 }
 
-void ProgramCompiler::compile(IO::Base &io)
+void ProgramCompiler::compile(IO::Base &io, Resources *res)
 {
+	resources = res;
 	module = &parser.parse(io);
 	process();
 }
@@ -38,11 +62,11 @@ void ProgramCompiler::add_shaders(Program &program)
 	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(head+apply<Formatter>(*i)));
 		else if(i->type==GEOMETRY)
-			program.attach_shader_owned(new GeometryShader(head+create_source(*i)));
+			program.attach_shader_owned(new GeometryShader(head+apply<Formatter>(*i)));
 		else if(i->type==FRAGMENT)
-			program.attach_shader_owned(new FragmentShader(head+create_source(*i)));
+			program.attach_shader_owned(new FragmentShader(head+apply<Formatter>(*i)));
 	}
 
 	program.bind_attribute(VERTEX4, "vertex");
@@ -51,8 +75,42 @@ void ProgramCompiler::add_shaders(Program &program)
 	program.bind_attribute(TEXCOORD4, "texcoord");
 }
 
+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()
 {
+	list<Import *> imports = apply<NodeGatherer<Import> >(module->shared);
+	for(list<Import *>::iterator i=imports.end(); i!=imports.begin(); )
+		import((*--i)->module);
+	apply<NodeRemover>(module->shared, set<Node *>(imports.begin(), imports.end()));
+
 	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(); )
@@ -64,6 +122,39 @@ void ProgramCompiler::process()
 	}
 }
 
+void ProgramCompiler::import(const string &name)
+{
+	if(!resources)
+		throw runtime_error("no resources");
+	RefPtr<IO::Seekable> io = resources->open_raw(name+".glsl");
+	if(!io)
+		throw runtime_error(format("module %s not found", name));
+	ProgramParser import_parser;
+	Module &imported_module = import_parser.parse(*io);
+
+	inject_block(module->shared.content, imported_module.shared.content);
+	apply<DeclarationCombiner>(module->shared);
+	for(list<Stage>::iterator i=imported_module.stages.begin(); i!=imported_module.stages.end(); ++i)
+	{
+		list<Stage>::iterator j;
+		for(j=module->stages.begin(); (j!=module->stages.end() && j->type<i->type); ++j) ;
+		if(j==module->stages.end() || j->type>i->type)
+		{
+			j = module->stages.insert(j, *i);
+			list<Stage>::iterator k = j;
+			if(++k!=module->stages.end())
+				k->previous = &*j;
+			if(j!=module->stages.begin())
+				j->previous = &*--(k=j);
+		}
+		else
+		{
+			inject_block(j->content, i->content);
+			apply<DeclarationCombiner>(*j);
+		}
+	}
+}
+
 void ProgramCompiler::generate(Stage &stage)
 {
 	inject_block(stage.content, module->shared.content);
@@ -76,14 +167,13 @@ void ProgramCompiler::generate(Stage &stage)
 
 bool ProgramCompiler::optimize(Stage &stage)
 {
-	UnusedVariableLocator unused_locator;
-	unused_locator.apply(stage);
+	apply<ConstantConditionEliminator>(stage);
+	apply<VariableResolver>(stage);
 
-	NodeRemover remover;
-	remover.to_remove = unused_locator.unused_nodes;
-	remover.apply(stage);
+	set<Node *> unused = apply<UnusedVariableLocator>(stage);
+	apply<NodeRemover>(stage, unused);
 
-	return remover.n_removed;
+	return !unused.empty();
 }
 
 void ProgramCompiler::inject_block(Block &target, const Block &source)
@@ -94,17 +184,19 @@ void ProgramCompiler::inject_block(Block &target, const Block &source)
 }
 
 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();
 }
 
 
@@ -122,7 +214,7 @@ void ProgramCompiler::Visitor::apply(Stage &s)
 ProgramCompiler::Formatter::Formatter():
 	indent(0),
 	parameter_list(false),
-	else_if(false)
+	else_if(0)
 { }
 
 void ProgramCompiler::Formatter::visit(Literal &literal)
@@ -160,14 +252,18 @@ 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);
@@ -188,31 +284,32 @@ 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+!formatted.empty());
 	string spaces(indent*2, ' ');
 	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(Import &import)
+{
+	formatted += format("import %s;", import.module);
 }
 
 void ProgramCompiler::Formatter::visit(Layout &layout)
@@ -242,7 +339,7 @@ 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)
@@ -263,6 +360,7 @@ 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 += ';';
@@ -279,7 +377,7 @@ void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 		(*i)->visit(*this);
 	}
 	formatted += ')';
-	if(func.definition)
+	if(func.definition==&func)
 	{
 		formatted += '\n';
 		func.body.visit(*this);
@@ -291,10 +389,9 @@ 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);
@@ -303,8 +400,8 @@ 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);
 	}
 }
@@ -329,10 +426,74 @@ void ProgramCompiler::Formatter::visit(Return &ret)
 }
 
 
+ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
+	toplevel(true),
+	remove_node(false)
+{ }
+
+void ProgramCompiler::DeclarationCombiner::visit(Block &block)
+{
+	if(!toplevel)
+		return;
+
+	SetForScope<bool> set(toplevel, false);
+	for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+	{
+		remove_node = false;
+		(*i)->visit(*this);
+		if(remove_node)
+			block.body.erase(i++);
+		else
+			++i;
+	}
+}
+
+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)
+	{
+		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);
@@ -356,6 +517,19 @@ 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)
@@ -380,7 +554,10 @@ 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);
 	}
@@ -391,6 +568,21 @@ 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);
@@ -407,6 +599,9 @@ 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)
@@ -416,6 +611,7 @@ 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);
 }
 
@@ -491,8 +687,12 @@ bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration
 	iface_var->type = var.type;
 	iface_var->type_declaration = var.type_declaration;
 	iface_var->name = name;
-	iface_var->array = (var.array || (stage->type==GEOMETRY && iface=="in"));
-	iface_var->array_size = var.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 = &var;
 	iface_declarations[name] = iface_var;
@@ -502,13 +702,12 @@ 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;
@@ -587,6 +786,24 @@ void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
 		}
 	}
 
+	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);
@@ -625,23 +842,196 @@ void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
 }
 
 
+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(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),
+	remove_node(false),
+	replacement_block(0)
+{ }
+
+void ProgramCompiler::ConstantConditionEliminator::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(replacement_block)
+		{
+			for(list<NodePtr<Node> >::iterator j=replacement_block->body.begin(); j!=replacement_block->body.end(); ++j)
+				block.body.insert(i, *j);
+			replacement_block = 0;
+		}
+
+		if(remove_node)
+			block.body.erase(i++);
+		else
+			++i;
+		remove_node = false;
+	}
+
+	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;
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
+{
+	ExpressionEvaluator eval(variable_values);
+	cond.condition->visit(eval);
+	if(eval.result_valid)
+	{
+		remove_node = true;
+		replacement_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():
-	assignment(false),
-	assignment_target(0)
+	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)
 {
-	if(assignment)
-		assignment_target = var.declaration;
-	else
+	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(); )
 	{
-		unused_nodes.erase(var.declaration);
-		map<VariableDeclaration *, Node *>::iterator i = assignments.find(var.declaration);
-		if(i!=assignments.end())
+		--j;
+		BlockAssignmentMap::iterator k = j->find(var.declaration);
+		if(k!=j->end())
 		{
-			unused_nodes.erase(i->second);
-			assignments.erase(i);
+			for(vector<Node *>::iterator l=k->second.nodes.begin(); l!=k->second.nodes.end(); ++l)
+				unused_nodes.erase(*l);
+			j->erase(k);
+			break;
 		}
 	}
 }
@@ -654,72 +1044,174 @@ void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
 
 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
 {
-	if(binary.assignment)
+	if(binary.oper=="[")
 	{
-		binary.right->visit(*this);
-		assignment = true;
 		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 = false;
-	assignment_target = 0;
+	assignment = 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;
+	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)
 {
-	unused_nodes.insert(&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);
+}
 
-ProgramCompiler::NodeRemover::NodeRemover():
-	n_removed(0),
-	immutable_block(false),
-	remove_block(false)
-{ }
+void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
+{
+	assignments.push_back(BlockAssignmentMap());
 
-void ProgramCompiler::NodeRemover::visit(Block &block)
+	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()
 {
-	remove_block = immutable_block;
-	for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
+	BlockAssignmentMap &parent_assignments = assignments[assignments.size()-2];
+	BlockAssignmentMap &block_assignments = assignments.back();
+	for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
 	{
-		bool remove = to_remove.count(&**i);
-		if(!remove)
-			remove_block = false;
-		(*i)->visit(*this);
+		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();
+}
 
-		if(remove ? !immutable_block : remove_block)
+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())
 		{
-			block.body.erase(i++);
-			++n_removed;
+			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;
+			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::NodeRemover::visit(StructDeclaration &strct)
+void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
 {
-	SetFlag set(immutable_block);
-	TraversingVisitor::visit(strct);
+	assignments.push_back(BlockAssignmentMap());
+	TraversingVisitor::visit(iter);
+	merge_down_assignments();
+}
+
+
+ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
+	to_remove(r)
+{ }
+
+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)
@@ -731,12 +1223,8 @@ void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
 		if(var.linked_declaration)
 			var.linked_declaration->linked_declaration = 0;
 	}
-}
-
-void ProgramCompiler::NodeRemover::visit(InterfaceBlock &iface)
-{
-	SetFlag set(immutable_block);
-	TraversingVisitor::visit(iface);
+	else if(var.init_expression && to_remove.count(&*var.init_expression))
+		var.init_expression = 0;
 }
 
 } // namespace GL