[2bb4a01] | 1 | // |
---|
| 2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo |
---|
| 3 | // |
---|
| 4 | // The contents of this file are covered under the licence agreement in the |
---|
| 5 | // file "LICENCE" distributed with Cforall. |
---|
| 6 | // |
---|
| 7 | // Node.hpp -- |
---|
| 8 | // |
---|
| 9 | // Author : Thierry Delisle |
---|
| 10 | // Created On : Wed May 8 10:27:04 2019 |
---|
[1e97287] | 11 | // Last Modified By : Andrew Beach |
---|
[dafe9e1] | 12 | // Last Modified On : Mon Jun 3 13:26:00 2019 |
---|
| 13 | // Update Count : 5 |
---|
[2bb4a01] | 14 | // |
---|
| 15 | |
---|
[cedb545] | 16 | #pragma once |
---|
| 17 | |
---|
[2bb4a01] | 18 | #include <cassert> |
---|
| 19 | #include <iosfwd> |
---|
[cedb545] | 20 | |
---|
[1346914] | 21 | #include "Common/ErrorObjects.h" // for SemanticErrorException |
---|
| 22 | |
---|
[cedb545] | 23 | namespace ast { |
---|
[2bb4a01] | 24 | |
---|
| 25 | class Visitor; |
---|
| 26 | |
---|
| 27 | /// Base class for all AST nodes. |
---|
| 28 | /// Keeps both strong and weak reference counts. |
---|
[f47f887] | 29 | class Node { |
---|
| 30 | public: |
---|
[14cebb7a] | 31 | // override defaults to ensure assignment doesn't |
---|
[2bb4a01] | 32 | // change/share reference counts |
---|
| 33 | Node() = default; |
---|
[6d51bd7] | 34 | Node(const Node&) : strong_count(0), weak_count(0) {} |
---|
| 35 | Node(Node&&) : strong_count(0), weak_count(0) {} |
---|
[2bb4a01] | 36 | Node& operator= (const Node&) = delete; |
---|
| 37 | Node& operator= (Node&&) = delete; |
---|
[f47f887] | 38 | virtual ~Node() = default; |
---|
[cedb545] | 39 | |
---|
[6d51bd7] | 40 | virtual const Node * accept( Visitor & v ) const = 0; |
---|
[2bb4a01] | 41 | |
---|
| 42 | /// Types of node references |
---|
[f47f887] | 43 | enum class ref_type { |
---|
| 44 | strong, |
---|
| 45 | weak |
---|
| 46 | }; |
---|
[cedb545] | 47 | |
---|
[4864a73] | 48 | bool unique() const { return strong_count == 1; } |
---|
| 49 | |
---|
[87701b6] | 50 | private: |
---|
| 51 | /// Make a copy of this node; should be overridden in subclass with more precise return type |
---|
| 52 | virtual Node * clone() const = 0; |
---|
| 53 | |
---|
| 54 | /// Must be copied in ALL derived classes |
---|
| 55 | template<typename node_t> |
---|
| 56 | friend node_t * mutate(const node_t * node); |
---|
| 57 | |
---|
| 58 | mutable size_t strong_count = 0; |
---|
| 59 | mutable size_t weak_count = 0; |
---|
[4864a73] | 60 | mutable bool was_ever_strong = false; |
---|
[87701b6] | 61 | |
---|
| 62 | void increment(ref_type ref) const { |
---|
[f47f887] | 63 | switch (ref) { |
---|
[4864a73] | 64 | case ref_type::strong: strong_count++; was_ever_strong = true; break; |
---|
[6d51bd7] | 65 | case ref_type::weak : weak_count ++; break; |
---|
[cedb545] | 66 | } |
---|
[f47f887] | 67 | } |
---|
[cedb545] | 68 | |
---|
[87701b6] | 69 | void decrement(ast::Node::ref_type ref) const { |
---|
[f47f887] | 70 | switch (ref) { |
---|
[6d51bd7] | 71 | case ref_type::strong: strong_count--; break; |
---|
| 72 | case ref_type::weak : weak_count --; break; |
---|
[cedb545] | 73 | } |
---|
| 74 | |
---|
[6d51bd7] | 75 | if(!strong_count && !weak_count) { |
---|
[f47f887] | 76 | delete this; |
---|
[6a625de] | 77 | } |
---|
[f47f887] | 78 | } |
---|
[6a625de] | 79 | |
---|
[87701b6] | 80 | template< typename node_t, enum Node::ref_type ref_t > |
---|
| 81 | friend class ptr_base; |
---|
[f47f887] | 82 | }; |
---|
| 83 | |
---|
| 84 | // Mutate a node, non-member function to avoid static type |
---|
| 85 | // problems and be able to use auto return |
---|
| 86 | template<typename node_t> |
---|
[87701b6] | 87 | node_t * mutate( const node_t * node ) { |
---|
| 88 | if (node->strong_count <= 1) { |
---|
[f47f887] | 89 | return const_cast<node_t *>(node); |
---|
[6a625de] | 90 | } |
---|
| 91 | |
---|
[f47f887] | 92 | assertf( |
---|
| 93 | node->weak_count == 0, |
---|
| 94 | "Error: mutating node with weak references to it will invalided some references" |
---|
| 95 | ); |
---|
| 96 | return node->clone(); |
---|
| 97 | } |
---|
| 98 | |
---|
[54e41b3] | 99 | std::ostream& operator<< ( std::ostream& out, const Node * node ); |
---|
[2bb4a01] | 100 | |
---|
[d8938622] | 101 | /// Call a visitor on a possibly-null node |
---|
| 102 | template<typename node_t> |
---|
| 103 | auto maybe_accept( const node_t * n, Visitor & v ) -> decltype( n->accept(v) ) { |
---|
| 104 | return n ? n->accept( v ) : nullptr; |
---|
| 105 | } |
---|
| 106 | |
---|
[1346914] | 107 | /// Call a visitor on a collection of nodes, throwing any exceptions when completed |
---|
| 108 | template< typename Container > |
---|
| 109 | void accept_each( const Container & c, Visitor & v ) { |
---|
| 110 | SemanticErrorException errors; |
---|
| 111 | for ( const auto & i : c ) { |
---|
| 112 | try { |
---|
| 113 | if ( i ) { |
---|
| 114 | i->accept( v ); |
---|
| 115 | } |
---|
| 116 | } catch ( SemanticErrorException & e ) { |
---|
| 117 | errors.append( e ); |
---|
| 118 | } |
---|
| 119 | } |
---|
| 120 | if ( ! errors.isEmpty() ) { |
---|
| 121 | throw errors; |
---|
| 122 | } |
---|
| 123 | } |
---|
| 124 | |
---|
[9e1d485] | 125 | /// Base class for the smart pointer types |
---|
| 126 | /// should never really be used. |
---|
| 127 | template< typename node_t, enum Node::ref_type ref_t > |
---|
[f47f887] | 128 | class ptr_base { |
---|
| 129 | public: |
---|
| 130 | ptr_base() : node(nullptr) {} |
---|
[87701b6] | 131 | ptr_base( const node_t * n ) : node(n) { if( node ) _inc(node); } |
---|
[dafe9e1] | 132 | ~ptr_base() { if( node ) { auto tmp = node; node = nullptr; _dec(tmp); } } |
---|
[f47f887] | 133 | |
---|
[f685679] | 134 | ptr_base( const ptr_base & o ) : node(o.node) { |
---|
| 135 | if( node ) _inc(node); |
---|
| 136 | } |
---|
| 137 | |
---|
[d76c588] | 138 | ptr_base( ptr_base && o ) : node(o.node) { o.node = nullptr; } |
---|
[f685679] | 139 | |
---|
[9e1d485] | 140 | template< enum Node::ref_type o_ref_t > |
---|
[f47f887] | 141 | ptr_base( const ptr_base<node_t, o_ref_t> & o ) : node(o.node) { |
---|
[87701b6] | 142 | if( node ) _inc(node); |
---|
[6a625de] | 143 | } |
---|
| 144 | |
---|
[9e1d485] | 145 | template< enum Node::ref_type o_ref_t > |
---|
[f47f887] | 146 | ptr_base( ptr_base<node_t, o_ref_t> && o ) : node(o.node) { |
---|
[87701b6] | 147 | if( node ) _inc(node); |
---|
[6d51bd7] | 148 | } |
---|
| 149 | |
---|
| 150 | template<typename o_node_t> |
---|
| 151 | ptr_base & operator=( const o_node_t * node ) { |
---|
[dafe9e1] | 152 | assign( strict_dynamic_cast<const node_t *, nullptr>(node) ); |
---|
[6d51bd7] | 153 | return *this; |
---|
[f47f887] | 154 | } |
---|
[cedb545] | 155 | |
---|
[f685679] | 156 | ptr_base & operator=( const ptr_base & o ) { |
---|
| 157 | assign(o.node); |
---|
| 158 | return *this; |
---|
| 159 | } |
---|
| 160 | |
---|
| 161 | ptr_base & operator=( ptr_base && o ) { |
---|
[d76c588] | 162 | if ( node == o.node ) return *this; |
---|
| 163 | if ( node ) _dec(node); |
---|
| 164 | node = o.node; |
---|
| 165 | o.node = nullptr; |
---|
[f685679] | 166 | return *this; |
---|
| 167 | } |
---|
| 168 | |
---|
[9e1d485] | 169 | template< enum Node::ref_type o_ref_t > |
---|
[f47f887] | 170 | ptr_base & operator=( const ptr_base<node_t, o_ref_t> & o ) { |
---|
| 171 | assign(o.node); |
---|
| 172 | return *this; |
---|
| 173 | } |
---|
[cedb545] | 174 | |
---|
[9e1d485] | 175 | template< enum Node::ref_type o_ref_t > |
---|
[f47f887] | 176 | ptr_base & operator=( ptr_base<node_t, o_ref_t> && o ) { |
---|
| 177 | assign(o.node); |
---|
| 178 | return *this; |
---|
| 179 | } |
---|
[cedb545] | 180 | |
---|
[4864a73] | 181 | const node_t * get() const { _check(); return node; } |
---|
| 182 | const node_t * operator->() const { _check(); return node; } |
---|
| 183 | const node_t & operator* () const { _check(); return *node; } |
---|
| 184 | explicit operator bool() const { _check(); return node; } |
---|
| 185 | operator const node_t * () const { _check(); return node; } |
---|
[cedb545] | 186 | |
---|
[54e41b3] | 187 | /// wrapper for convenient access to dynamic_cast |
---|
[fdbd4fd] | 188 | template<typename o_node_t> |
---|
[4864a73] | 189 | const o_node_t * as() const { _check(); return dynamic_cast<const o_node_t *>(node); } |
---|
[fdbd4fd] | 190 | |
---|
[ee574a2] | 191 | /// wrapper for convenient access to strict_dynamic_cast |
---|
| 192 | template<typename o_node_t> |
---|
| 193 | const o_node_t * strict_as() const { return strict_dynamic_cast<const o_node_t *>(node); } |
---|
| 194 | |
---|
[76ed81f] | 195 | /// Returns a mutable version of the pointer in this node. |
---|
| 196 | node_t * get_and_mutate(); |
---|
| 197 | |
---|
[54e41b3] | 198 | /// Sets this pointer to a mutated version of a pointer (possibly) owned elsehere. |
---|
| 199 | /// Returns a mutable version of the pointer in this node. |
---|
[10a1225] | 200 | node_t * set_and_mutate( const node_t * n ); |
---|
[54e41b3] | 201 | |
---|
[f47f887] | 202 | using ptr = const node_t *; |
---|
[cedb545] | 203 | |
---|
[f47f887] | 204 | private: |
---|
[9e1d485] | 205 | void assign( const node_t * other ) { |
---|
[87701b6] | 206 | if( other ) _inc(other); |
---|
| 207 | if( node ) _dec(node ); |
---|
[f47f887] | 208 | node = other; |
---|
| 209 | } |
---|
[cedb545] | 210 | |
---|
[87701b6] | 211 | void _inc( const node_t * other ); |
---|
| 212 | void _dec( const node_t * other ); |
---|
[4864a73] | 213 | void _check() const; |
---|
[87701b6] | 214 | |
---|
[f47f887] | 215 | protected: |
---|
[9e1d485] | 216 | const node_t * node; |
---|
[f47f887] | 217 | }; |
---|
[cedb545] | 218 | |
---|
[2bb4a01] | 219 | /// Owning pointer to node |
---|
[f47f887] | 220 | template< typename node_t > |
---|
| 221 | using ptr = ptr_base< node_t, Node::ref_type::strong >; |
---|
[cedb545] | 222 | |
---|
[2bb4a01] | 223 | /// Observing pointer to node |
---|
[f47f887] | 224 | template< typename node_t > |
---|
| 225 | using readonly = ptr_base< node_t, Node::ref_type::weak >; |
---|
[2bb4a01] | 226 | } |
---|
| 227 | |
---|
| 228 | // Local Variables: // |
---|
| 229 | // tab-width: 4 // |
---|
| 230 | // mode: c++ // |
---|
| 231 | // compile-command: "make install" // |
---|
[1e97287] | 232 | // End: // |
---|