Refactor FunctionInliner to do any necessary declaration reordering

[libs/gl.git] / source / glsl / optimize.h

diff --git a/source/glsl/optimize.h b/source/glsl/optimize.h
index 2caa498da0512624a31734232dfca88e870f6b31..eae90399542d3130ba38e08c24d87f6f13a7ff50 100644 (file)
--- a/source/glsl/optimize.h
+++ b/source/glsl/optimize.h
@@ -10,6 +10,8 @@ namespace Msp {
 namespace GL {
 namespace SL {
 
+/** Finds functions which are candidates for inlining.  Currently this means
+functions which have no parameters and are only called once. */
 class InlineableFunctionLocator: private TraversingVisitor
 {
 private:
@@ -20,25 +22,46 @@ private:
 public:
        InlineableFunctionLocator();
 
-       const std::set<FunctionDeclaration *> &apply(Stage &s) { visit(s.content); return inlineable; }
+       const std::set<FunctionDeclaration *> &apply(Stage &s) { s.content.visit(*this); return inlineable; }
 
 private:
        virtual void visit(FunctionCall &);
        virtual void visit(FunctionDeclaration &);
-       using TraversingVisitor::visit;
 };
 
+/** Collects declarations referenced by a function. */
+class InlineDependencyCollector: private TraversingVisitor
+{
+private:
+       std::set<Node *> dependencies;
+
+public:
+       const std::set<Node *> &apply(FunctionDeclaration &f) { f.visit(*this); return dependencies; }
+
+private:
+       virtual void visit(VariableReference &);
+       virtual void visit(InterfaceBlockReference &);
+       virtual void visit(FunctionCall &);
+       virtual void visit(VariableDeclaration &);
+};
+
+/** Inlines functions.  Internally uses InlineableFunctionLocator to find
+candidate functions.  Only functions which consist of a single return statement
+are inlined. */
 class FunctionInliner: private TraversingVisitor
 {
 private:
+       Stage *stage;
        std::set<FunctionDeclaration *> inlineable;
+       FunctionDeclaration *current_function;
        unsigned extract_result;
        RefPtr<Expression> inline_result;
+       bool any_inlined;
 
 public:
        FunctionInliner();
 
-       void apply(Stage &);
+       bool apply(Stage &);
 
 private:
        void visit_and_inline(RefPtr<Expression> &);
@@ -49,10 +72,12 @@ private:
        virtual void visit(MemberAccess &);
        virtual void visit(FunctionCall &);
        virtual void visit(VariableDeclaration &);
+       virtual void visit(FunctionDeclaration &);
        virtual void visit(Return &);
-       using TraversingVisitor::visit;
 };
 
+/** Removes conditional statements and loops where the condition can be
+determined as constant at compile time. */
 class ConstantConditionEliminator: private TraversingVisitor
 {
 private:
@@ -73,9 +98,10 @@ private:
        virtual void visit(VariableDeclaration &);
        virtual void visit(Conditional &);
        virtual void visit(Iteration &);
-       using TraversingVisitor::visit;
 };
 
+/** Removes variable declarations with no references to them.  Assignment
+statements where the result is not used are also removed. */
 class UnusedVariableRemover: private TraversingVisitor
 {
 private:
@@ -106,6 +132,7 @@ public:
 
 private:
        virtual void visit(VariableReference &);
+       virtual void visit(InterfaceBlockReference &);
        virtual void visit(MemberAccess &);
        virtual void visit(BinaryExpression &);
        virtual void visit(Assignment &);
@@ -119,9 +146,9 @@ private:
        void merge_down_variables();
        virtual void visit(Conditional &);
        virtual void visit(Iteration &);
-       using TraversingVisitor::visit;
 };
 
+/** Removes function declarations with no references to them. */
 class UnusedFunctionRemover: private TraversingVisitor
 {
 private:
@@ -134,7 +161,6 @@ public:
 private:
        virtual void visit(FunctionCall &);
        virtual void visit(FunctionDeclaration &);
-       using TraversingVisitor::visit;
 };
 
 } // namespace SL