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 0c87acf0b953a40198b60299f4288b57a0c59cbe..f585ba92347ae52e580eec7c5d42ce993fc8c483 100644 (file)
--- a/source/programcompiler.h
+++ b/source/programcompiler.h
@@ -136,6 +136,39 @@ 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