Remove conditionals and loops that can be determined to never run

[libs/gl.git] / source / programcompiler.h

diff --git a/source/programcompiler.h b/source/programcompiler.h
index 34b64b557ca29a9185dc2f5e2aacaa1420bbf325..f585ba92347ae52e580eec7c5d42ce993fc8c483 100644 (file)
--- a/source/programcompiler.h
+++ b/source/programcompiler.h
@@ -9,28 +9,36 @@ namespace Msp {
 namespace GL {
 
 class Program;
+class Resources;
 
 class ProgramCompiler
 {
 private:
        struct Visitor: ProgramSyntax::TraversingVisitor
        {
+               typedef void ResultType;
+
                ProgramSyntax::Stage *stage;
 
                Visitor();
 
                virtual void apply(ProgramSyntax::Stage &);
+               void get_result() const { }
        };
 
        struct Formatter: Visitor
        {
+               typedef std::string ResultType;
+
                std::string formatted;
                unsigned indent;
                bool parameter_list;
-               bool else_if;
+               unsigned else_if;
+               std::string block_interface;
 
                Formatter();
 
+               const std::string &get_result() const { return formatted; }
                virtual void visit(ProgramSyntax::Block &);
                virtual void visit(ProgramSyntax::Literal &);
                virtual void visit(ProgramSyntax::ParenthesizedExpression &);
@@ -38,8 +46,10 @@ private:
                virtual void visit(ProgramSyntax::MemberAccess &);
                virtual void visit(ProgramSyntax::UnaryExpression &);
                virtual void visit(ProgramSyntax::BinaryExpression &);
+               virtual void visit(ProgramSyntax::Assignment &);
                virtual void visit(ProgramSyntax::FunctionCall &);
                virtual void visit(ProgramSyntax::ExpressionStatement &);
+               virtual void visit(ProgramSyntax::Import &);
                virtual void visit(ProgramSyntax::Layout &);
                virtual void visit(ProgramSyntax::StructDeclaration &);
                virtual void visit(ProgramSyntax::VariableDeclaration &);
@@ -50,18 +60,49 @@ private:
                virtual void visit(ProgramSyntax::Return &);
        };
 
+       template<typename T>
+       struct NodeGatherer: Visitor
+       {
+               typedef std::list<T *> ResultType;
+
+               std::list<T *> nodes;
+
+               const ResultType &get_result() const { return nodes; }
+               virtual void visit(T &n) { nodes.push_back(&n); }
+       };
+
+       struct DeclarationCombiner: Visitor
+       {
+               bool toplevel;
+               std::map<std::string, std::vector<ProgramSyntax::FunctionDeclaration *> > functions;
+               std::map<std::string, ProgramSyntax::VariableDeclaration *> variables;
+               bool remove_node;
+
+               DeclarationCombiner();
+
+               virtual void visit(ProgramSyntax::Block &);
+               virtual void visit(ProgramSyntax::FunctionDeclaration &);
+               virtual void visit(ProgramSyntax::VariableDeclaration &);
+       };
+
        struct VariableResolver: Visitor
        {
                std::vector<ProgramSyntax::Block *> blocks;
                ProgramSyntax::StructDeclaration *type;
                bool anonymous;
+               std::string block_interface;
+               bool record_target;
+               ProgramSyntax::VariableDeclaration *assignment_target;
+               bool self_referencing;
 
                VariableResolver();
 
+               virtual void apply(ProgramSyntax::Stage &);
                virtual void visit(ProgramSyntax::Block &);
                virtual void visit(ProgramSyntax::VariableReference &);
                virtual void visit(ProgramSyntax::MemberAccess &);
                virtual void visit(ProgramSyntax::BinaryExpression &);
+               virtual void visit(ProgramSyntax::Assignment &);
                virtual void visit(ProgramSyntax::StructDeclaration &);
                virtual void visit(ProgramSyntax::VariableDeclaration &);
                virtual void visit(ProgramSyntax::InterfaceBlock &);
@@ -95,37 +136,89 @@ private:
                virtual void visit(ProgramSyntax::VariableDeclaration &);
        };
 
+       struct ExpressionEvaluator: ProgramSyntax::NodeVisitor
+       {
+               typedef std::map<ProgramSyntax::VariableDeclaration *, ProgramSyntax::Expression *> ValueMap;
+
+               const ValueMap *variable_values;
+               float result;
+               bool result_valid;
+
+               ExpressionEvaluator();
+               ExpressionEvaluator(const ValueMap &);
+
+               virtual void visit(ProgramSyntax::Literal &);
+               virtual void visit(ProgramSyntax::VariableReference &);
+               virtual void visit(ProgramSyntax::UnaryExpression &);
+               virtual void visit(ProgramSyntax::BinaryExpression &);
+       };
+
+       struct ConstantConditionEliminator: Visitor
+       {
+               unsigned scope_level;
+               ExpressionEvaluator::ValueMap variable_values;
+               bool remove_node;
+               ProgramSyntax::Block *replacement_block;
+
+               ConstantConditionEliminator();
+
+               virtual void visit(ProgramSyntax::Block &);
+               virtual void visit(ProgramSyntax::Assignment &);
+               virtual void visit(ProgramSyntax::VariableDeclaration &);
+               virtual void visit(ProgramSyntax::Conditional &);
+               virtual void visit(ProgramSyntax::Iteration &);
+       };
+
        struct UnusedVariableLocator: Visitor
        {
+               struct AssignmentList
+               {
+                       std::vector<ProgramSyntax::Node *> nodes;
+                       bool conditional;
+                       bool self_referencing;
+               };
+
+               typedef std::set<ProgramSyntax::Node *> ResultType;
+               typedef std::map<ProgramSyntax::VariableDeclaration *, AssignmentList> BlockAssignmentMap;
+
                std::set<ProgramSyntax::Node *> unused_nodes;
-               std::map<ProgramSyntax::VariableDeclaration *, ProgramSyntax::Node *> assignments;
-               bool assignment;
-               ProgramSyntax::VariableDeclaration *assignment_target;
+               std::map<ProgramSyntax::VariableDeclaration *, ProgramSyntax::Node *> aggregates;
+               ProgramSyntax::Node *aggregate;
+               std::vector<BlockAssignmentMap> assignments;
+               ProgramSyntax::Assignment *assignment;
+               bool assignment_target;
 
                UnusedVariableLocator();
 
+               virtual void apply(ProgramSyntax::Stage &);
+               const ResultType &get_result() const { return unused_nodes; }
                virtual void visit(ProgramSyntax::VariableReference &);
                virtual void visit(ProgramSyntax::MemberAccess &);
                virtual void visit(ProgramSyntax::BinaryExpression &);
+               virtual void visit(ProgramSyntax::Assignment &);
+               void record_assignment(ProgramSyntax::VariableDeclaration &, ProgramSyntax::Node &, bool);
                virtual void visit(ProgramSyntax::ExpressionStatement &);
+               virtual void visit(ProgramSyntax::StructDeclaration &);
                virtual void visit(ProgramSyntax::VariableDeclaration &);
+               virtual void visit(ProgramSyntax::InterfaceBlock &);
+               virtual void visit(ProgramSyntax::FunctionDeclaration &);
+               void merge_down_assignments();
+               virtual void visit(ProgramSyntax::Conditional &);
+               virtual void visit(ProgramSyntax::Iteration &);
        };
 
        struct NodeRemover: Visitor
        {
                std::set<ProgramSyntax::Node *> to_remove;
-               unsigned n_removed;
-               bool immutable_block;
-               bool remove_block;
 
-               NodeRemover();
+               NodeRemover() { }
+               NodeRemover(const std::set<ProgramSyntax::Node *> &);
 
                virtual void visit(ProgramSyntax::Block &);
-               virtual void visit(ProgramSyntax::StructDeclaration &);
                virtual void visit(ProgramSyntax::VariableDeclaration &);
-               virtual void visit(ProgramSyntax::InterfaceBlock &);
        };
 
+       Resources *resources;
        ProgramParser parser;
        ProgramSyntax::Module *module;
 
@@ -133,17 +226,22 @@ public:
        ProgramCompiler();
 
        void compile(const std::string &);
-       void compile(IO::Base &);
+       void compile(IO::Base &, Resources * = 0);
        void add_shaders(Program &);
 
 private:
+       static ProgramSyntax::Module *create_builtins_module();
+       static ProgramSyntax::Module &get_builtins_module();
+       static ProgramSyntax::Stage *get_builtins(ProgramSyntax::StageType);
        void process();
+       void import(const std::string &);
        void generate(ProgramSyntax::Stage &);
        bool optimize(ProgramSyntax::Stage &);
        static void inject_block(ProgramSyntax::Block &, const ProgramSyntax::Block &);
        template<typename T>
-       static void apply(ProgramSyntax::Stage &);
-       std::string create_source(ProgramSyntax::Stage &);
+       static typename T::ResultType apply(ProgramSyntax::Stage &);
+       template<typename T, typename A>
+       static typename T::ResultType apply(ProgramSyntax::Stage &, const A &);
 };
 
 } // namespace GL