1 | // |
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2 | // Cforall Version 1.0.0 Copyright (C) 2019 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 | // Pass.impl.hpp -- |
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8 | // |
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9 | // Author : Thierry Delisle |
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10 | // Created On : Thu May 09 15::37::05 2019 |
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11 | // Last Modified By : |
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12 | // Last Modified On : |
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13 | // Update Count : |
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14 | // |
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15 | |
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16 | #pragma once |
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17 | // IWYU pragma: private, include "AST/Pass.hpp" |
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18 | |
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19 | #include <type_traits> |
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20 | #include <unordered_map> |
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21 | |
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22 | #define VISIT_START( node ) \ |
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23 | using namespace ast; \ |
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24 | /* back-up the visit children */ \ |
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25 | __attribute__((unused)) ast::__pass::visit_children_guard guard1( ast::__pass::visit_children(pass, 0) ); \ |
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26 | /* setup the scope for passes that want to run code at exit */ \ |
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27 | __attribute__((unused)) ast::__pass::guard_value guard2( ast::__pass::at_cleanup (pass, 0) ); \ |
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28 | /* call the implementation of the previsit of this pass */ \ |
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29 | __pass::previsit( pass, node, 0 ); |
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30 | |
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31 | #define VISIT( code... ) \ |
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32 | /* if this node should visit its children */ \ |
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33 | if ( __visit_children() ) { \ |
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34 | /* visit the children */ \ |
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35 | code \ |
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36 | } |
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37 | |
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38 | #define VISIT_END( type, node ) \ |
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39 | /* call the implementation of the postvisit of this pass */ \ |
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40 | auto __return = __pass::postvisit( pass, node, 0 ); \ |
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41 | assertf(__return, "post visit should never return null"); \ |
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42 | return __return; |
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43 | |
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44 | #ifdef PEDANTIC_PASS_ASSERT |
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45 | #define __pedantic_pass_assert(...) assert (__VA_ARGS__) |
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46 | #define __pedantic_pass_assertf(...) assertf(__VA_ARGS__) |
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47 | #else |
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48 | #define __pedantic_pass_assert(...) |
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49 | #define __pedantic_pass_assertf(...) |
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50 | #endif |
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51 | |
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52 | namespace ast { |
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53 | namespace __pass { |
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54 | // Check if this is either a null pointer or a pointer to an empty container |
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55 | template<typename T> |
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56 | static inline bool empty( T * ptr ) { |
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57 | return !ptr || ptr->empty(); |
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58 | } |
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59 | |
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60 | //------------------------------ |
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61 | template<typename it_t, template <class...> class container_t> |
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62 | static inline void take_all( it_t it, container_t<ast::ptr<ast::Decl>> * decls, bool * mutated = nullptr ) { |
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63 | if(empty(decls)) return; |
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64 | |
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65 | std::transform(decls->begin(), decls->end(), it, [](const ast::Decl * decl) -> auto { |
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66 | return new DeclStmt( decl ); |
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67 | }); |
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68 | decls->clear(); |
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69 | if(mutated) *mutated = true; |
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70 | } |
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71 | |
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72 | template<typename it_t, template <class...> class container_t> |
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73 | static inline void take_all( it_t it, container_t<ast::ptr<ast::Stmt>> * decls, bool * mutated = nullptr ) { |
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74 | if(empty(decls)) return; |
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75 | |
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76 | std::move(decls->begin(), decls->end(), it); |
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77 | decls->clear(); |
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78 | if(mutated) *mutated = true; |
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79 | } |
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80 | |
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81 | //------------------------------ |
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82 | /// Check if should be skipped, different for pointers and containers |
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83 | template<typename node_t> |
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84 | bool skip( const ast::ptr<node_t> & val) { |
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85 | return !val; |
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86 | } |
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87 | |
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88 | template< template <class...> class container_t, typename node_t > |
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89 | bool skip( const container_t<ast::ptr< node_t >> & val ) { |
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90 | return val.empty(); |
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91 | } |
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92 | |
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93 | //------------------------------ |
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94 | /// Get the value to visit, different for pointers and containers |
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95 | template<typename node_t> |
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96 | auto get( const ast::ptr<node_t> & val, int ) -> decltype(val.get()) { |
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97 | return val.get(); |
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98 | } |
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99 | |
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100 | template<typename node_t> |
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101 | const node_t & get( const node_t & val, long) { |
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102 | return val; |
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103 | } |
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104 | |
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105 | |
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106 | //------------------------------ |
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107 | /// Check if value was mutated, different for pointers and containers |
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108 | template<typename lhs_t, typename rhs_t> |
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109 | bool differs( const lhs_t * old_val, const rhs_t * new_val ) { |
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110 | return old_val != new_val; |
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111 | } |
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112 | |
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113 | template< template <class...> class container_t, typename node_t > |
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114 | bool differs( const container_t<ast::ptr< node_t >> &, const container_t<ast::ptr< node_t >> & new_val ) { |
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115 | return !new_val.empty(); |
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116 | } |
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117 | } |
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118 | |
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119 | template< typename pass_t > |
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120 | template< typename node_t > |
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121 | auto Pass< pass_t >::call_accept( const node_t * node ) -> decltype( node->accept(*this) ) { |
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122 | __pedantic_pass_assert( __visit_children() ); |
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123 | __pedantic_pass_assert( expr ); |
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124 | |
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125 | static_assert( !std::is_base_of<ast::Expr, node_t>::value, "ERROR"); |
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126 | static_assert( !std::is_base_of<ast::Stmt, node_t>::value, "ERROR"); |
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127 | |
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128 | return node->accept( *this ); |
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129 | } |
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130 | |
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131 | template< typename pass_t > |
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132 | const ast::Expr * Pass< pass_t >::call_accept( const ast::Expr * expr ) { |
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133 | __pedantic_pass_assert( __visit_children() ); |
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134 | __pedantic_pass_assert( expr ); |
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135 | |
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136 | const ast::TypeSubstitution ** env_ptr = __pass::env( pass, 0); |
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137 | if ( env_ptr && expr->env ) { |
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138 | *env_ptr = expr->env; |
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139 | } |
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140 | |
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141 | return expr->accept( *this ); |
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142 | } |
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143 | |
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144 | template< typename pass_t > |
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145 | const ast::Stmt * Pass< pass_t >::call_accept( const ast::Stmt * stmt ) { |
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146 | __pedantic_pass_assert( __visit_children() ); |
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147 | __pedantic_pass_assert( stmt ); |
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148 | |
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149 | // add a few useful symbols to the scope |
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150 | using __pass::empty; |
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151 | |
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152 | // get the stmts/decls that will need to be spliced in |
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153 | auto stmts_before = __pass::stmtsToAddBefore( pass, 0); |
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154 | auto stmts_after = __pass::stmtsToAddAfter ( pass, 0); |
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155 | auto decls_before = __pass::declsToAddBefore( pass, 0); |
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156 | auto decls_after = __pass::declsToAddAfter ( pass, 0); |
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157 | |
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158 | // These may be modified by subnode but most be restored once we exit this statemnet. |
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159 | ValueGuardPtr< const ast::TypeSubstitution * > __old_env ( __pass::env( pass, 0) ); |
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160 | ValueGuardPtr< typename std::remove_pointer< decltype(stmts_before) > > __old_decls_before( stmts_before ); |
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161 | ValueGuardPtr< typename std::remove_pointer< decltype(stmts_after ) > > __old_decls_after ( stmts_after ); |
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162 | ValueGuardPtr< typename std::remove_pointer< decltype(decls_before) > > __old_stmts_before( decls_before ); |
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163 | ValueGuardPtr< typename std::remove_pointer< decltype(decls_after ) > > __old_stmts_after ( decls_after ); |
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164 | |
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165 | // Now is the time to actually visit the node |
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166 | const ast::Stmt * nstmt = stmt->accept( *this ); |
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167 | |
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168 | // If the pass doesn't want to add anything then we are done |
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169 | if( empty(stmts_before) && empty(stmts_after) && empty(decls_before) && empty(decls_after) ) { |
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170 | return nstmt; |
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171 | } |
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172 | |
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173 | // Make sure that it is either adding statements or declartions but not both |
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174 | // this is because otherwise the order would be awkward to predict |
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175 | assert(( empty( stmts_before ) && empty( stmts_after )) |
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176 | || ( empty( decls_before ) && empty( decls_after )) ); |
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177 | |
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178 | // Create a new Compound Statement to hold the new decls/stmts |
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179 | ast::CompoundStmt * compound = new ast::CompoundStmt( stmt->location ); |
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180 | |
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181 | // Take all the declarations that go before |
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182 | __pass::take_all( std::back_inserter( compound->kids ), decls_before ); |
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183 | __pass::take_all( std::back_inserter( compound->kids ), stmts_before ); |
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184 | |
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185 | // Insert the original declaration |
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186 | compound->kids.emplace_back( nstmt ); |
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187 | |
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188 | // Insert all the declarations that go before |
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189 | __pass::take_all( std::back_inserter( compound->kids ), decls_after ); |
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190 | __pass::take_all( std::back_inserter( compound->kids ), stmts_after ); |
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191 | |
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192 | return compound; |
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193 | } |
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194 | |
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195 | template< typename pass_t > |
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196 | template< template <class...> class container_t > |
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197 | container_t< ptr<Stmt> > Pass< pass_t >::call_accept( const container_t< ptr<Stmt> > & statements ) { |
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198 | __pedantic_pass_assert( __visit_children() ); |
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199 | if( statements.empty() ) return {}; |
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200 | |
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201 | // We are going to aggregate errors for all these statements |
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202 | SemanticErrorException errors; |
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203 | |
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204 | // add a few useful symbols to the scope |
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205 | using __pass::empty; |
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206 | |
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207 | // get the stmts/decls that will need to be spliced in |
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208 | auto stmts_before = __pass::stmtsToAddBefore( pass, 0); |
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209 | auto stmts_after = __pass::stmtsToAddAfter ( pass, 0); |
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210 | auto decls_before = __pass::declsToAddBefore( pass, 0); |
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211 | auto decls_after = __pass::declsToAddAfter ( pass, 0); |
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212 | |
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213 | // These may be modified by subnode but most be restored once we exit this statemnet. |
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214 | ValueGuardPtr< typename std::remove_pointer< decltype(stmts_before) > > __old_decls_before( stmts_before ); |
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215 | ValueGuardPtr< typename std::remove_pointer< decltype(stmts_after ) > > __old_decls_after ( stmts_after ); |
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216 | ValueGuardPtr< typename std::remove_pointer< decltype(decls_before) > > __old_stmts_before( decls_before ); |
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217 | ValueGuardPtr< typename std::remove_pointer< decltype(decls_after ) > > __old_stmts_after ( decls_after ); |
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218 | |
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219 | // update pass statitistics |
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220 | pass_visitor_stats.depth++; |
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221 | pass_visitor_stats.max->push(pass_visitor_stats.depth); |
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222 | pass_visitor_stats.avg->push(pass_visitor_stats.depth); |
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223 | |
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224 | bool mutated = false; |
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225 | container_t< ptr<Stmt> > new_kids; |
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226 | for( const Stmt * stmt : statements ) { |
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227 | try { |
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228 | __pedantic_pass_assert( stmt ); |
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229 | const ast::Stmt * new_stmt = stmt->accept( *this ); |
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230 | assert( new_stmt ); |
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231 | if(new_stmt != stmt ) mutated = true; |
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232 | |
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233 | // Make sure that it is either adding statements or declartions but not both |
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234 | // this is because otherwise the order would be awkward to predict |
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235 | assert(( empty( stmts_before ) && empty( stmts_after )) |
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236 | || ( empty( decls_before ) && empty( decls_after )) ); |
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237 | |
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238 | |
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239 | |
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240 | // Take all the statements which should have gone after, N/A for first iteration |
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241 | __pass::take_all( std::back_inserter( new_kids ), decls_before, &mutated ); |
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242 | __pass::take_all( std::back_inserter( new_kids ), stmts_before, &mutated ); |
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243 | |
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244 | // Now add the statement if there is one |
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245 | new_kids.emplace_back( new_stmt ); |
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246 | |
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247 | // Take all the declarations that go before |
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248 | __pass::take_all( std::back_inserter( new_kids ), decls_after, &mutated ); |
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249 | __pass::take_all( std::back_inserter( new_kids ), stmts_after, &mutated ); |
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250 | } |
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251 | catch ( SemanticErrorException &e ) { |
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252 | errors.append( e ); |
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253 | } |
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254 | } |
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255 | pass_visitor_stats.depth--; |
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256 | if ( !errors.isEmpty() ) { throw errors; } |
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257 | |
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258 | return mutated ? new_kids : container_t< ptr<Stmt> >(); |
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259 | } |
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260 | |
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261 | template< typename pass_t > |
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262 | template< template <class...> class container_t, typename node_t > |
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263 | container_t< ast::ptr<node_t> > Pass< pass_t >::call_accept( const container_t< ast::ptr<node_t> > & container ) { |
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264 | __pedantic_pass_assert( __visit_children() ); |
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265 | if( container.empty() ) return {}; |
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266 | SemanticErrorException errors; |
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267 | |
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268 | pass_visitor_stats.depth++; |
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269 | pass_visitor_stats.max->push(pass_visitor_stats.depth); |
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270 | pass_visitor_stats.avg->push(pass_visitor_stats.depth); |
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271 | |
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272 | bool mutated = false; |
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273 | container_t< ast::ptr<node_t> > new_kids; |
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274 | for ( const node_t * node : container ) { |
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275 | try { |
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276 | __pedantic_pass_assert( node ); |
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277 | const node_t * new_stmt = strict_dynamic_cast< const node_t * >( node->accept( *this ) ); |
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278 | if(new_stmt != node ) mutated = true; |
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279 | |
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280 | new_kids.emplace_back( new_stmt ); |
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281 | } |
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282 | catch( SemanticErrorException &e ) { |
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283 | errors.append( e ); |
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284 | } |
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285 | } |
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286 | pass_visitor_stats.depth--; |
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287 | if ( ! errors.isEmpty() ) { throw errors; } |
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288 | |
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289 | return mutated ? new_kids : container_t< ast::ptr<node_t> >(); |
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290 | } |
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291 | |
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292 | template< typename pass_t > |
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293 | template<typename node_t, typename parent_t, typename child_t> |
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294 | void Pass< pass_t >::maybe_accept( |
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295 | const node_t * & parent, |
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296 | child_t parent_t::*child |
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297 | ) { |
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298 | static_assert( std::is_base_of<parent_t, node_t>::value, "Error deductiing member object" ); |
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299 | |
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300 | if(__pass::skip(parent->*child)) return; |
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301 | const auto & old_val = __pass::get(parent->*child, 0); |
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302 | |
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303 | static_assert( !std::is_same<const ast::Node * &, decltype(old_val)>::value, "ERROR"); |
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304 | |
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305 | auto new_val = call_accept( old_val ); |
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306 | |
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307 | static_assert( !std::is_same<const ast::Node *, decltype(new_val)>::value || std::is_same<int, decltype(old_val)>::value, "ERROR"); |
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308 | |
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309 | if( __pass::differs(old_val, new_val) ) { |
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310 | auto new_parent = mutate(parent); |
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311 | new_parent->*child = new_val; |
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312 | parent = new_parent; |
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313 | } |
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314 | } |
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315 | |
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316 | } |
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317 | |
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318 | //------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
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319 | //======================================================================================================================================================================== |
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320 | //======================================================================================================================================================================== |
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321 | //======================================================================================================================================================================== |
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322 | //======================================================================================================================================================================== |
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323 | //======================================================================================================================================================================== |
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324 | //------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
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325 | |
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326 | template< typename pass_t > |
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327 | inline void ast::accept_all( std::list< ast::ptr<ast::Decl> > & decls, ast::Pass< pass_t > & visitor ) { |
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328 | // We are going to aggregate errors for all these statements |
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329 | SemanticErrorException errors; |
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330 | |
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331 | // add a few useful symbols to the scope |
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332 | using __pass::empty; |
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333 | |
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334 | // get the stmts/decls that will need to be spliced in |
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335 | auto decls_before = __pass::declsToAddBefore( visitor.pass, 0); |
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336 | auto decls_after = __pass::declsToAddAfter ( visitor.pass, 0); |
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337 | |
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338 | // update pass statitistics |
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339 | pass_visitor_stats.depth++; |
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340 | pass_visitor_stats.max->push(pass_visitor_stats.depth); |
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341 | pass_visitor_stats.avg->push(pass_visitor_stats.depth); |
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342 | |
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343 | for ( std::list< ast::ptr<ast::Decl> >::iterator i = decls.begin(); ; ++i ) { |
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344 | // splice in new declarations after previous decl |
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345 | if ( !empty( decls_after ) ) { decls.splice( i, *decls_after ); } |
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346 | |
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347 | if ( i == decls.end() ) break; |
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348 | |
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349 | try { |
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350 | // run visitor on declaration |
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351 | ast::ptr<ast::Decl> & node = *i; |
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352 | assert( node ); |
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353 | node = node->accept( visitor ); |
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354 | } |
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355 | catch( SemanticErrorException &e ) { |
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356 | errors.append( e ); |
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357 | } |
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358 | |
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359 | // splice in new declarations before current decl |
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360 | if ( !empty( decls_before ) ) { decls.splice( i, *decls_before ); } |
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361 | } |
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362 | pass_visitor_stats.depth--; |
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363 | if ( !errors.isEmpty() ) { throw errors; } |
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364 | } |
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365 | |
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366 | // A NOTE ON THE ORDER OF TRAVERSAL |
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367 | // |
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368 | // Types and typedefs have their base types visited before they are added to the type table. This is ok, since there is |
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369 | // no such thing as a recursive type or typedef. |
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370 | // |
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371 | // typedef struct { T *x; } T; // never allowed |
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372 | // |
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373 | // for structs/unions, it is possible to have recursion, so the decl should be added as if it's incomplete to begin, the |
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374 | // members are traversed, and then the complete type should be added (assuming the type is completed by this particular |
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375 | // declaration). |
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376 | // |
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377 | // struct T { struct T *x; }; // allowed |
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378 | // |
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379 | // It is important to add the complete type to the symbol table *after* the members/base has been traversed, since that |
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380 | // traversal may modify the definition of the type and these modifications should be visible when the symbol table is |
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381 | // queried later in this pass. |
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382 | |
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383 | //-------------------------------------------------------------------------- |
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384 | // ObjectDecl |
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385 | template< typename pass_t > |
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386 | const ast::DeclWithType * ast::Pass< pass_t >::visit( const ast::ObjectDecl * node ) { |
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387 | VISIT_START( node ); |
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388 | |
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389 | VISIT( |
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390 | { |
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391 | guard_indexer guard { *this }; |
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392 | maybe_accept( node, &ast::ObjectDecl::type ); |
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393 | } |
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394 | maybe_accept( node, &ast::ObjectDecl::init ); |
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395 | maybe_accept( node, &ast::ObjectDecl::bitfieldWidth ); |
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396 | maybe_accept( node, &ast::ObjectDecl::attributes ); |
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397 | ) |
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398 | |
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399 | __pass::indexer::addId( pass, 0, node ); |
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400 | |
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401 | VISIT_END( DeclWithType, node ); |
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402 | } |
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403 | |
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404 | //-------------------------------------------------------------------------- |
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405 | // SingleInit |
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406 | template< typename pass_t > |
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407 | const ast::Init * ast::Pass< pass_t >::visit( const ast::SingleInit * node ) { |
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408 | VISIT_START( node ); |
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409 | |
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410 | VISIT( |
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411 | maybe_accept( node, &SingleInit::value ); |
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412 | ) |
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413 | |
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414 | VISIT_END( Init, node ); |
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415 | } |
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416 | |
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417 | //-------------------------------------------------------------------------- |
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418 | // ListInit |
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419 | template< typename pass_t > |
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420 | const ast::Init * ast::Pass< pass_t >::visit( const ast::ListInit * node ) { |
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421 | VISIT_START( node ); |
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422 | |
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423 | VISIT( |
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424 | maybe_accept( node, &ListInit::designations ); |
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425 | maybe_accept( node, &ListInit::initializers ); |
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426 | ) |
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427 | |
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428 | VISIT_END( Init, node ); |
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429 | } |
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430 | |
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431 | //-------------------------------------------------------------------------- |
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432 | // ConstructorInit |
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433 | template< typename pass_t > |
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434 | const ast::Init * ast::Pass< pass_t >::visit( const ast::ConstructorInit * node ) { |
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435 | VISIT_START( node ); |
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436 | |
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437 | VISIT( |
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438 | maybe_accept( node, &ConstructorInit::ctor ); |
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439 | maybe_accept( node, &ConstructorInit::dtor ); |
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440 | maybe_accept( node, &ConstructorInit::init ); |
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441 | ) |
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442 | |
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443 | VISIT_END( Init, node ); |
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444 | } |
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445 | |
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446 | //-------------------------------------------------------------------------- |
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447 | // Attribute |
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448 | template< typename pass_t > |
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449 | const ast::Attribute * ast::Pass< pass_t >::visit( const ast::Attribute * node ) { |
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450 | VISIT_START( node ); |
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451 | |
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452 | VISIT( |
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453 | maybe_accept( node, &Attribute::parameters ); |
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454 | ) |
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455 | |
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456 | VISIT_END( Attribute *, node ); |
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457 | } |
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458 | |
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459 | //-------------------------------------------------------------------------- |
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460 | // TypeSubstitution |
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461 | template< typename pass_t > |
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462 | const ast::TypeSubstitution * ast::Pass< pass_t >::visit( const ast::TypeSubstitution * node ) { |
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463 | VISIT_START( node ); |
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464 | |
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465 | VISIT( |
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466 | { |
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467 | bool mutated = false; |
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468 | std::unordered_map< std::string, ast::ptr< ast::Type > > new_map; |
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469 | for ( const auto & p : node->typeEnv ) { |
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470 | guard_indexer guard { *this }; |
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471 | auto new_node = p.second->accept( *this ); |
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472 | if (new_node != p.second) mutated = false; |
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473 | new_map.insert({ p.first, new_node }); |
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474 | } |
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475 | if (mutated) { |
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476 | auto new_node = mutate( node ); |
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477 | new_node->typeEnv.swap( new_map ); |
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478 | node = new_node; |
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479 | } |
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480 | } |
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481 | |
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482 | { |
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483 | bool mutated = false; |
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484 | std::unordered_map< std::string, ast::ptr< ast::Expr > > new_map; |
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485 | for ( const auto & p : node->varEnv ) { |
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486 | guard_indexer guard { *this }; |
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487 | auto new_node = p.second->accept( *this ); |
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488 | if (new_node != p.second) mutated = false; |
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489 | new_map.insert({ p.first, new_node }); |
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490 | } |
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491 | if (mutated) { |
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492 | auto new_node = mutate( node ); |
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493 | new_node->varEnv.swap( new_map ); |
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494 | node = new_node; |
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495 | } |
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496 | } |
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497 | ) |
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498 | |
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499 | VISIT_END( TypeSubstitution, node ); |
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500 | } |
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501 | |
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502 | #undef VISIT_START |
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503 | #undef VISIT |
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504 | #undef VISIT_END |
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