1 /* 2 * Copyright 2016 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SKSL_PROGRAMELEMENT 9 #define SKSL_PROGRAMELEMENT 10 11 #include "include/private/SkSLIRNode.h" 12 13 #include <memory> 14 15 namespace SkSL { 16 17 /** 18 * Represents a top-level element (e.g. function or global variable) in a program. 19 */ 20 class ProgramElement : public IRNode { 21 public: 22 enum class Kind { 23 kExtension = 0, 24 kFunction, 25 kFunctionPrototype, 26 kGlobalVar, 27 kInterfaceBlock, 28 kModifiers, 29 kStructDefinition, 30 31 kFirst = kExtension, 32 kLast = kStructDefinition 33 }; 34 ProgramElement(int offset,Kind kind)35 ProgramElement(int offset, Kind kind) 36 : INHERITED(offset, (int) kind) { 37 SkASSERT(kind >= Kind::kFirst && kind <= Kind::kLast); 38 } 39 kind()40 Kind kind() const { 41 return (Kind) fKind; 42 } 43 44 /** 45 * Use is<T> to check the type of a program element. 46 * e.g. replace `el.kind() == ProgramElement::Kind::kExtension` with `el.is<Extension>()`. 47 */ 48 template <typename T> is()49 bool is() const { 50 return this->kind() == T::kProgramElementKind; 51 } 52 53 /** 54 * Use as<T> to downcast program elements. e.g. replace `(Extension&) el` with 55 * `el.as<Extension>()`. 56 */ 57 template <typename T> as()58 const T& as() const { 59 SkASSERT(this->is<T>()); 60 return static_cast<const T&>(*this); 61 } 62 63 template <typename T> as()64 T& as() { 65 SkASSERT(this->is<T>()); 66 return static_cast<T&>(*this); 67 } 68 69 virtual std::unique_ptr<ProgramElement> clone() const = 0; 70 71 private: 72 using INHERITED = IRNode; 73 }; 74 75 } // namespace SkSL 76 77 #endif 78