SkSL performance improvements

src/sksl/SkSLIRGenerator.h

Index: src/sksl/SkSLIRGenerator.h
diff --git a/src/sksl/SkSLIRGenerator.h b/src/sksl/SkSLIRGenerator.h
index d23e5a1bdb3a31eb1e901febbce4d70f0290413e..73847f1cb651afc14291858886489a3422880db6 100644
--- a/src/sksl/SkSLIRGenerator.h
+++ b/src/sksl/SkSLIRGenerator.h
@@ -62,24 +62,23 @@ public:
     std::unique_ptr<Expression> convertExpression(const ASTExpression& expression);
 
 private:
-    void pushSymbolTable();
+    void pushSymbolTable(bool owner = false);
     void popSymbolTable();
 
-    std::shared_ptr<Type> convertType(const ASTType& type);
+    const Type* convertType(const ASTType& type);
     std::unique_ptr<Expression> call(Position position, 
-                                     std::shared_ptr<FunctionDeclaration> function, 
+                                     const FunctionDeclaration& function, 
                                      std::vector<std::unique_ptr<Expression>> arguments);
-    bool determineCallCost(std::shared_ptr<FunctionDeclaration> function, 
+    bool determineCallCost(const FunctionDeclaration& function, 
                            const std::vector<std::unique_ptr<Expression>>& arguments,
                            int* outCost);
     std::unique_ptr<Expression> call(Position position, std::unique_ptr<Expression> function, 
                                      std::vector<std::unique_ptr<Expression>> arguments);
-    std::unique_ptr<Expression> coerce(std::unique_ptr<Expression> expr, 
-                                       std::shared_ptr<Type> type);
+    std::unique_ptr<Expression> coerce(std::unique_ptr<Expression> expr, const Type& type);
     std::unique_ptr<Block> convertBlock(const ASTBlock& block);
     std::unique_ptr<Statement> convertBreak(const ASTBreakStatement& b);
     std::unique_ptr<Expression> convertConstructor(Position position, 
-                                                   std::shared_ptr<Type> type, 
+                                                   const Type& type, 
                                                    std::vector<std::unique_ptr<Expression>> params);
     std::unique_ptr<Statement> convertContinue(const ASTContinueStatement& c);
     std::unique_ptr<Statement> convertDiscard(const ASTDiscardStatement& d);
@@ -106,10 +105,10 @@ private:
     std::unique_ptr<Statement> convertWhile(const ASTWhileStatement& w);
 
     void checkValid(const Expression& expr);
-    void markReadFrom(std::shared_ptr<Variable> var);
+    void markReadFrom(const Variable& var);
     void markWrittenTo(const Expression& expr);
 
-    std::shared_ptr<FunctionDeclaration> fCurrentFunction;
+    const FunctionDeclaration* fCurrentFunction;
     std::shared_ptr<SymbolTable> fSymbolTable;
     ErrorReporter& fErrors;