[68f9c43] | 1 | // |
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo |
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| 3 | // |
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| 4 | // The contents of this file are covered under the licence agreement in the |
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| 5 | // file "LICENCE" distributed with Cforall. |
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| 6 | // |
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| 7 | // GC.h -- |
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| 8 | // |
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| 9 | // Author : Aaron B. Moss |
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| 10 | // Created On : Thu Mar 15 14:47:00 2018 |
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| 11 | // Last Modified By : Aaron B. Moss |
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| 12 | // Last Modified On : Thu Mar 15 14:47:00 2018 |
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| 13 | // Update Count : 1 |
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| 14 | // |
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| 15 | |
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| 16 | #pragma once |
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| 17 | |
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| 18 | #include <vector> |
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| 19 | |
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| 20 | class GC_Object; |
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[bd06384] | 21 | class BaseSyntaxNode; |
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[68f9c43] | 22 | |
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| 23 | /// Manually traced and called garbage collector |
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| 24 | class GC { |
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| 25 | friend class GcTracer; |
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| 26 | public: |
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| 27 | /// Gets singleton GC instance |
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| 28 | static GC& get(); |
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| 29 | |
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| 30 | /// Traces a traceable object |
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[24de7b1] | 31 | const GC& operator<< (const GC_Object*) const; |
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[68f9c43] | 32 | |
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| 33 | /// Adds a new object to garbage collection |
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| 34 | void register_object(GC_Object*); |
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| 35 | |
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[bd06384] | 36 | /// Adds an object to the set of static roots |
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| 37 | void register_static_root(BaseSyntaxNode*); |
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| 38 | |
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[04570c7] | 39 | /// Start new generation for subsequent new objects |
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[68f9c43] | 40 | void new_generation(); |
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| 41 | |
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[bd06384] | 42 | /// Traces all static roots |
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| 43 | void trace_static_roots(); |
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| 44 | |
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[04570c7] | 45 | /// Collects the youngest generation, placing survivors in previous generation. |
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| 46 | /// Young generation objects cannot be kept alive by pointers from older generation. |
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| 47 | /// Older generation is used for subsequent new objects. |
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[68f9c43] | 48 | void collect_young(); |
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| 49 | |
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[04570c7] | 50 | /// Collects oldest generation; use oldest generation afterward. |
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| 51 | /// Error if currently using younger generation |
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[68f9c43] | 52 | void collect(); |
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| 53 | |
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| 54 | /// Collects all contained objects |
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| 55 | ~GC(); |
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| 56 | |
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| 57 | private: |
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| 58 | GC(); |
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| 59 | |
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[bd06384] | 60 | using Generation = std::vector<GC_Object*>; |
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[04570c7] | 61 | std::vector<Generation> gens; ///< Set of generations; always at least one |
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[68f9c43] | 62 | |
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[bd06384] | 63 | using StaticRoots = std::vector<BaseSyntaxNode*>; |
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[04570c7] | 64 | StaticRoots static_roots; ///< Set of static-lifetime roots |
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| 65 | |
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| 66 | bool mark; ///< The current collection's mark bit |
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| 67 | unsigned g; ///< The current number generation in use |
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[68f9c43] | 68 | }; |
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| 69 | |
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| 70 | /// Use young generation until next collection |
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| 71 | inline void new_generation() { GC::get().new_generation(); } |
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| 72 | |
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[bfc7811] | 73 | // /// no-op default trace |
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| 74 | // template<typename T> |
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| 75 | // inline const GC& operator<< (const GC& gc, const T& x) { return gc; } |
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[68f9c43] | 76 | |
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[8d7bef2] | 77 | inline void traceAll(const GC&) {} |
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[68f9c43] | 78 | |
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| 79 | /// Marks all arguments as live in current generation |
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| 80 | template<typename T, typename... Args> |
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| 81 | inline void traceAll(const GC& gc, T& x, Args&... xs) { |
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| 82 | gc << x; |
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| 83 | traceAll(gc, xs...); |
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| 84 | } |
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| 85 | |
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| 86 | /// Traces young-generation roots and does a young collection |
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| 87 | template<typename... Args> |
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| 88 | inline void collect_young(Args&... roots) { |
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| 89 | GC& gc = GC::get(); |
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| 90 | traceAll(gc, roots...); |
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[bd06384] | 91 | gc.trace_static_roots(); |
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[68f9c43] | 92 | gc.collect_young(); |
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| 93 | } |
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| 94 | |
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| 95 | /// Traces roots and collects other elements |
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| 96 | template<typename... Args> |
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| 97 | inline void collect(Args&... roots) { |
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| 98 | GC& gc = GC::get(); |
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| 99 | traceAll(gc, roots...); |
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[bd06384] | 100 | gc.trace_static_roots(); |
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[68f9c43] | 101 | gc.collect(); |
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| 102 | } |
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| 103 | |
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[bd06384] | 104 | /// Makes a new expression as a static root |
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| 105 | template<typename T, typename... Args> |
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| 106 | inline T* new_static_root( Args&&... args ) { |
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| 107 | T* root = new T( std::forward<Args>(args)... ); |
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| 108 | GC::get().register_static_root( root ); |
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| 109 | return root; |
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| 110 | } |
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| 111 | |
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[24de7b1] | 112 | /// Class that is managed by the GC |
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| 113 | class GC_Object { |
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[68f9c43] | 114 | friend class GC; |
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| 115 | protected: |
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[8d7bef2] | 116 | mutable bool mark; |
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| 117 | |
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[24de7b1] | 118 | // Override default constructors to ensure clones are registered and properly marked |
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| 119 | GC_Object(); |
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[68f9c43] | 120 | |
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[24de7b1] | 121 | GC_Object(const GC_Object&); |
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| 122 | |
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| 123 | GC_Object(GC_Object&&); |
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| 124 | |
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| 125 | GC_Object& operator= (const GC_Object&) { /* do not assign mark */ return *this; } |
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| 126 | |
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| 127 | GC_Object& operator= (GC_Object&&) { /* do not assign mark */ return *this; } |
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| 128 | |
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| 129 | // Ensure subclasses can be deleted by garbage collector |
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[68f9c43] | 130 | virtual ~GC_Object() {} |
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[24de7b1] | 131 | |
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| 132 | /// override to trace any child objects |
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| 133 | virtual void trace(const GC&) const {} |
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[68f9c43] | 134 | }; |
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| 135 | |
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| 136 | // Local Variables: // |
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| 137 | // tab-width: 4 // |
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| 138 | // mode: c++ // |
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| 139 | // compile-command: "make install" // |
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| 140 | // End: // |
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