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 | // ExceptVisitor.cc -- |
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8 | // |
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9 | // Author : Andrew Beach |
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10 | // Created On : Wed Jun 14 16:49:00 2017 |
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11 | // Last Modified By : Andrew Beach |
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12 | // Last Modified On : Wed Jun 24 11:18:00 2020 |
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13 | // Update Count : 17 |
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14 | // |
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15 | |
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16 | #include "ExceptTranslate.h" |
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17 | |
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18 | #include <stddef.h> // for NULL |
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19 | #include <cassert> // for assert, assertf |
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20 | #include <iterator> // for back_inserter, inserter |
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21 | #include <string> // for string, operator== |
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22 | |
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23 | #include "Common/PassVisitor.h" // for PassVisitor, WithGuards |
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24 | #include "Common/SemanticError.h" // for SemanticError |
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25 | #include "Common/utility.h" // for CodeLocation |
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26 | #include "SynTree/LinkageSpec.h" // for Cforall |
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27 | #include "SynTree/Attribute.h" // for Attribute |
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28 | #include "SynTree/Constant.h" // for Constant |
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29 | #include "SynTree/Declaration.h" // for ObjectDecl, FunctionDecl, Struc... |
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30 | #include "SynTree/Expression.h" // for UntypedExpr, ConstantExpr, Name... |
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31 | #include "SynTree/Initializer.h" // for SingleInit, ListInit |
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32 | #include "SynTree/Label.h" // for Label |
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33 | #include "SynTree/Mutator.h" // for mutateAll |
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34 | #include "SynTree/Statement.h" // for CompoundStmt, CatchStmt, ThrowStmt |
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35 | #include "SynTree/Type.h" // for FunctionType, Type, noQualifiers |
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36 | #include "SynTree/DeclReplacer.h" // for DeclReplacer |
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37 | #include "SynTree/Visitor.h" // for acceptAll |
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38 | |
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39 | namespace ControlStruct { |
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40 | |
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41 | // Buricratic Helpers (Not having to do with the paritular operation.) |
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42 | |
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43 | typedef std::list<CatchStmt*> CatchList; |
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44 | |
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45 | void split( CatchList& allHandlers, CatchList& terHandlers, |
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46 | CatchList& resHandlers ) { |
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47 | while ( !allHandlers.empty() ) { |
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48 | CatchStmt * stmt = allHandlers.front(); |
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49 | allHandlers.pop_front(); |
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50 | if (CatchStmt::Terminate == stmt->get_kind()) { |
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51 | terHandlers.push_back(stmt); |
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52 | } else { |
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53 | resHandlers.push_back(stmt); |
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54 | } |
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55 | } |
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56 | } |
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57 | |
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58 | void appendDeclStmt( CompoundStmt * block, Declaration * item ) { |
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59 | block->push_back(new DeclStmt(item)); |
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60 | } |
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61 | |
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62 | Expression * nameOf( DeclarationWithType * decl ) { |
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63 | return new VariableExpr( decl ); |
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64 | } |
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65 | |
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66 | class ThrowMutatorCore : public WithGuards { |
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67 | ObjectDecl * terminate_handler_except; |
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68 | enum Context { NoHandler, TerHandler, ResHandler } cur_context; |
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69 | |
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70 | // The helper functions for code/syntree generation. |
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71 | Statement * create_either_throw( |
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72 | ThrowStmt * throwStmt, const char * throwFunc ); |
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73 | Statement * create_terminate_rethrow( ThrowStmt * throwStmt ); |
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74 | |
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75 | public: |
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76 | ThrowMutatorCore() : |
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77 | terminate_handler_except( nullptr ), |
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78 | cur_context( NoHandler ) |
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79 | {} |
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80 | |
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81 | void premutate( CatchStmt *catchStmt ); |
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82 | Statement * postmutate( ThrowStmt *throwStmt ); |
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83 | }; |
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84 | |
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85 | // ThrowStmt Mutation Helpers |
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86 | |
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87 | Statement * ThrowMutatorCore::create_either_throw( |
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88 | ThrowStmt * throwStmt, const char * throwFunc ) { |
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89 | // `throwFunc`( `throwStmt->get_name()` ); |
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90 | UntypedExpr * call = new UntypedExpr( new NameExpr( throwFunc ) ); |
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91 | call->get_args().push_back( throwStmt->get_expr() ); |
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92 | throwStmt->set_expr( nullptr ); |
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93 | delete throwStmt; |
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94 | return new ExprStmt( call ); |
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95 | } |
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96 | |
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97 | Statement * ThrowMutatorCore::create_terminate_rethrow( |
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98 | ThrowStmt *throwStmt ) { |
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99 | // { `terminate_handler_except` = 0p; __rethrow_terminate(); } |
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100 | assert( nullptr == throwStmt->get_expr() ); |
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101 | assert( terminate_handler_except ); |
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102 | |
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103 | CompoundStmt * result = new CompoundStmt(); |
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104 | result->labels = throwStmt->labels; |
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105 | result->push_back( new ExprStmt( UntypedExpr::createAssign( |
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106 | nameOf( terminate_handler_except ), |
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107 | new ConstantExpr( Constant::null( |
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108 | terminate_handler_except->get_type()->clone() |
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109 | ) ) |
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110 | ) ) ); |
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111 | result->push_back( new ExprStmt( |
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112 | new UntypedExpr( new NameExpr( "__cfaehm_rethrow_terminate" ) ) |
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113 | ) ); |
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114 | delete throwStmt; |
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115 | return result; |
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116 | } |
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117 | |
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118 | // Visiting/Mutating Functions |
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119 | |
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120 | void ThrowMutatorCore::premutate( CatchStmt *catchStmt ) { |
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121 | // Validate the statement's form. |
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122 | ObjectDecl * decl = dynamic_cast<ObjectDecl *>( catchStmt->get_decl() ); |
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123 | // Also checking the type would be nice. |
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124 | if ( !decl || !dynamic_cast<PointerType *>( decl->type ) ) { |
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125 | std::string kind = (CatchStmt::Terminate == catchStmt->kind) ? "catch" : "catchResume"; |
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126 | SemanticError( catchStmt->location, kind + " must have pointer to an exception type" ); |
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127 | } |
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128 | |
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129 | // Track the handler context. |
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130 | GuardValue( cur_context ); |
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131 | if ( CatchStmt::Terminate == catchStmt->get_kind() ) { |
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132 | cur_context = TerHandler; |
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133 | |
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134 | GuardValue( terminate_handler_except ); |
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135 | terminate_handler_except = decl; |
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136 | } else { |
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137 | cur_context = ResHandler; |
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138 | } |
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139 | } |
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140 | |
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141 | Statement * ThrowMutatorCore::postmutate( ThrowStmt *throwStmt ) { |
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142 | // Ignoring throwStmt->get_target() for now. |
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143 | if ( ThrowStmt::Terminate == throwStmt->get_kind() ) { |
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144 | if ( throwStmt->get_expr() ) { |
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145 | return create_either_throw( throwStmt, "$throw" ); |
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146 | } else if ( TerHandler == cur_context ) { |
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147 | return create_terminate_rethrow( throwStmt ); |
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148 | } else { |
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149 | abort("Invalid throw in %s at %i\n", |
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150 | throwStmt->location.filename.c_str(), |
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151 | throwStmt->location.first_line); |
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152 | } |
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153 | } else { |
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154 | if ( throwStmt->get_expr() ) { |
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155 | return create_either_throw( throwStmt, "$throwResume" ); |
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156 | } else if ( ResHandler == cur_context ) { |
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157 | // This has to be handled later. |
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158 | return throwStmt; |
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159 | } else { |
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160 | abort("Invalid throwResume in %s at %i\n", |
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161 | throwStmt->location.filename.c_str(), |
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162 | throwStmt->location.first_line); |
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163 | } |
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164 | } |
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165 | } |
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166 | |
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167 | class TryMutatorCore { |
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168 | // The built in types used in translation. |
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169 | StructDecl * except_decl; |
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170 | StructDecl * node_decl; |
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171 | StructDecl * hook_decl; |
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172 | |
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173 | // The many helper functions for code/syntree generation. |
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174 | CompoundStmt * take_try_block( TryStmt * tryStmt ); |
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175 | FunctionDecl * create_try_wrapper( CompoundStmt * body ); |
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176 | FunctionDecl * create_terminate_catch( CatchList &handlers ); |
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177 | CompoundStmt * create_single_matcher( |
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178 | DeclarationWithType * except_obj, CatchStmt * modded_handler ); |
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179 | FunctionDecl * create_terminate_match( CatchList &handlers ); |
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180 | CompoundStmt * create_terminate_caller( FunctionDecl * try_wrapper, |
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181 | FunctionDecl * terminate_catch, FunctionDecl * terminate_match ); |
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182 | FunctionDecl * create_resume_handler( CatchList &handlers ); |
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183 | CompoundStmt * create_resume_wrapper( |
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184 | Statement * wraps, FunctionDecl * resume_handler ); |
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185 | FunctionDecl * create_finally_wrapper( TryStmt * tryStmt ); |
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186 | ObjectDecl * create_finally_hook( FunctionDecl * finally_wrapper ); |
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187 | Statement * create_resume_rethrow( ThrowStmt * throwStmt ); |
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188 | |
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189 | // Types used in translation, make sure to use clone. |
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190 | // void (*function)(); |
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191 | FunctionType try_func_t; |
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192 | // void (*function)(int, exception); |
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193 | FunctionType catch_func_t; |
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194 | // int (*function)(exception); |
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195 | FunctionType match_func_t; |
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196 | // bool (*function)(exception); |
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197 | FunctionType handle_func_t; |
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198 | // void (*function)(__attribute__((unused)) void *); |
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199 | FunctionType finally_func_t; |
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200 | |
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201 | StructInstType * create_except_type() { |
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202 | assert( except_decl ); |
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203 | return new StructInstType( noQualifiers, except_decl ); |
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204 | } |
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205 | void init_func_types(); |
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206 | |
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207 | public: |
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208 | TryMutatorCore() : |
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209 | except_decl( nullptr ), node_decl( nullptr ), hook_decl( nullptr ), |
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210 | try_func_t( noQualifiers, false ), |
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211 | catch_func_t( noQualifiers, false ), |
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212 | match_func_t( noQualifiers, false ), |
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213 | handle_func_t( noQualifiers, false ), |
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214 | finally_func_t( noQualifiers, false ) |
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215 | {} |
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216 | |
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217 | void premutate( StructDecl *structDecl ); |
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218 | Statement * postmutate( TryStmt *tryStmt ); |
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219 | Statement * postmutate( ThrowStmt *throwStmt ); |
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220 | }; |
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221 | |
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222 | void TryMutatorCore::init_func_types() { |
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223 | assert( except_decl ); |
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224 | |
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225 | ObjectDecl index_obj( |
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226 | "__handler_index", |
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227 | Type::StorageClasses(), |
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228 | LinkageSpec::Cforall, |
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229 | /*bitfieldWidth*/ NULL, |
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230 | new BasicType( noQualifiers, BasicType::SignedInt ), |
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231 | /*init*/ NULL |
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232 | ); |
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233 | ObjectDecl exception_obj( |
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234 | "__exception_inst", |
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235 | Type::StorageClasses(), |
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236 | LinkageSpec::Cforall, |
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237 | /*bitfieldWidth*/ NULL, |
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238 | new PointerType( |
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239 | noQualifiers, |
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240 | new StructInstType( noQualifiers, except_decl ) |
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241 | ), |
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242 | /*init*/ NULL |
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243 | ); |
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244 | ObjectDecl bool_obj( |
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245 | "__ret_bool", |
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246 | Type::StorageClasses(), |
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247 | LinkageSpec::Cforall, |
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248 | /*bitfieldWidth*/ NULL, |
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249 | new BasicType( noQualifiers, BasicType::Bool ), |
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250 | /*init*/ NULL, |
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251 | std::list<Attribute *>{ new Attribute( "unused" ) } |
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252 | ); |
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253 | ObjectDecl voidptr_obj( |
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254 | "__hook", |
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255 | Type::StorageClasses(), |
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256 | LinkageSpec::Cforall, |
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257 | NULL, |
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258 | new PointerType( |
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259 | noQualifiers, |
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260 | new VoidType( |
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261 | noQualifiers |
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262 | ), |
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263 | std::list<Attribute *>{ new Attribute( "unused" ) } |
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264 | ), |
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265 | NULL |
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266 | ); |
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267 | |
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268 | ObjectDecl * unused_index_obj = index_obj.clone(); |
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269 | unused_index_obj->attributes.push_back( new Attribute( "unused" ) ); |
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270 | |
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271 | catch_func_t.get_parameters().push_back( index_obj.clone() ); |
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272 | catch_func_t.get_parameters().push_back( exception_obj.clone() ); |
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273 | match_func_t.get_returnVals().push_back( unused_index_obj ); |
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274 | match_func_t.get_parameters().push_back( exception_obj.clone() ); |
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275 | handle_func_t.get_returnVals().push_back( bool_obj.clone() ); |
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276 | handle_func_t.get_parameters().push_back( exception_obj.clone() ); |
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277 | finally_func_t.get_parameters().push_back( voidptr_obj.clone() ); |
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278 | } |
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279 | |
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280 | // TryStmt Mutation Helpers |
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281 | |
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282 | CompoundStmt * TryMutatorCore::take_try_block( TryStmt *tryStmt ) { |
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283 | CompoundStmt * block = tryStmt->get_block(); |
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284 | tryStmt->set_block( nullptr ); |
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285 | return block; |
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286 | } |
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287 | |
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288 | FunctionDecl * TryMutatorCore::create_try_wrapper( |
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289 | CompoundStmt *body ) { |
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290 | |
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291 | return new FunctionDecl( "try", Type::StorageClasses(), |
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292 | LinkageSpec::Cforall, try_func_t.clone(), body ); |
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293 | } |
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294 | |
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295 | FunctionDecl * TryMutatorCore::create_terminate_catch( |
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296 | CatchList &handlers ) { |
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297 | std::list<CaseStmt *> handler_wrappers; |
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298 | |
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299 | FunctionType *func_type = catch_func_t.clone(); |
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300 | DeclarationWithType * index_obj = func_type->get_parameters().front(); |
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301 | DeclarationWithType * except_obj = func_type->get_parameters().back(); |
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302 | |
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303 | // Index 1..{number of handlers} |
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304 | int index = 0; |
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305 | CatchList::iterator it = handlers.begin(); |
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306 | for ( ; it != handlers.end() ; ++it ) { |
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307 | ++index; |
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308 | CatchStmt * handler = *it; |
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309 | |
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310 | // case `index`: |
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311 | // { |
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312 | // `handler.decl` = { (virtual `decl.type`)`except` }; |
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313 | // `handler.body`; |
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314 | // } |
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315 | // return; |
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316 | CompoundStmt * block = new CompoundStmt(); |
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317 | |
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318 | // Just copy the exception value. (Post Validation) |
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319 | ObjectDecl * handler_decl = |
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320 | static_cast<ObjectDecl *>( handler->get_decl() ); |
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321 | ObjectDecl * local_except = handler_decl->clone(); |
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322 | local_except->set_init( |
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323 | new ListInit({ new SingleInit( |
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324 | new VirtualCastExpr( nameOf( except_obj ), |
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325 | local_except->get_type() |
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326 | ) |
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327 | ) }) |
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328 | ); |
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329 | block->push_back( new DeclStmt( local_except ) ); |
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330 | |
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331 | // Add the cleanup attribute. |
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332 | local_except->get_attributes().push_back( new Attribute( |
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333 | "cleanup", |
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334 | { new NameExpr( "__cfaehm_cleanup_terminate" ) } |
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335 | ) ); |
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336 | |
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337 | // Update variables in the body to point to this local copy. |
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338 | { |
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339 | DeclReplacer::DeclMap mapping; |
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340 | mapping[ handler_decl ] = local_except; |
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341 | DeclReplacer::replace( handler->body, mapping ); |
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342 | } |
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343 | |
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344 | block->push_back( handler->body ); |
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345 | handler->body = nullptr; |
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346 | |
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347 | std::list<Statement *> caseBody |
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348 | { block, new ReturnStmt( nullptr ) }; |
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349 | handler_wrappers.push_back( new CaseStmt( |
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350 | new ConstantExpr( Constant::from_int( index ) ), |
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351 | caseBody |
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352 | ) ); |
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353 | } |
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354 | // TODO: Some sort of meaningful error on default perhaps? |
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355 | |
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356 | std::list<Statement*> stmt_handlers; |
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357 | while ( !handler_wrappers.empty() ) { |
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358 | stmt_handlers.push_back( handler_wrappers.front() ); |
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359 | handler_wrappers.pop_front(); |
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360 | } |
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361 | |
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362 | SwitchStmt * handler_lookup = new SwitchStmt( |
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363 | nameOf( index_obj ), |
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364 | stmt_handlers |
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365 | ); |
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366 | CompoundStmt * body = new CompoundStmt(); |
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367 | body->push_back( handler_lookup ); |
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368 | |
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369 | return new FunctionDecl("catch", Type::StorageClasses(), |
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370 | LinkageSpec::Cforall, func_type, body); |
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371 | } |
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372 | |
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373 | // Create a single check from a moddified handler. |
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374 | // except_obj is referenced, modded_handler will be freed. |
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375 | CompoundStmt * TryMutatorCore::create_single_matcher( |
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376 | DeclarationWithType * except_obj, CatchStmt * modded_handler ) { |
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377 | // { |
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378 | // `modded_handler.decl` |
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379 | // if ( `decl.name = (virtual `decl.type`)`except` |
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380 | // [&& `modded_handler.cond`] ) { |
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381 | // `modded_handler.body` |
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382 | // } |
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383 | // } |
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384 | |
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385 | CompoundStmt * block = new CompoundStmt(); |
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386 | |
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387 | // Local Declaration |
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388 | ObjectDecl * local_except = |
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389 | dynamic_cast<ObjectDecl *>( modded_handler->get_decl() ); |
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390 | assert( local_except ); |
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391 | block->push_back( new DeclStmt( local_except ) ); |
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392 | |
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393 | // Check for type match. |
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394 | Expression * cond = UntypedExpr::createAssign( nameOf( local_except ), |
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395 | new VirtualCastExpr( nameOf( except_obj ), |
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396 | local_except->get_type()->clone() ) ); |
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397 | |
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398 | // Add the check on the conditional if it is provided. |
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399 | if ( modded_handler->get_cond() ) { |
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400 | cond = new LogicalExpr( cond, modded_handler->get_cond() ); |
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401 | } |
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402 | // Construct the match condition. |
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403 | block->push_back( new IfStmt( |
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404 | cond, modded_handler->get_body(), nullptr ) ); |
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405 | |
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406 | modded_handler->set_decl( nullptr ); |
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407 | modded_handler->set_cond( nullptr ); |
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408 | modded_handler->set_body( nullptr ); |
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409 | delete modded_handler; |
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410 | return block; |
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411 | } |
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412 | |
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413 | FunctionDecl * TryMutatorCore::create_terminate_match( |
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414 | CatchList &handlers ) { |
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415 | // int match(exception * except) { |
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416 | // HANDLER WRAPPERS { return `index`; } |
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417 | // } |
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418 | |
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419 | CompoundStmt * body = new CompoundStmt(); |
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420 | |
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421 | FunctionType * func_type = match_func_t.clone(); |
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422 | DeclarationWithType * except_obj = func_type->get_parameters().back(); |
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423 | |
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424 | // Index 1..{number of handlers} |
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425 | int index = 0; |
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426 | CatchList::iterator it; |
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427 | for ( it = handlers.begin() ; it != handlers.end() ; ++it ) { |
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428 | ++index; |
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429 | CatchStmt * handler = *it; |
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430 | |
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431 | // Body should have been taken by create_terminate_catch. |
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432 | assert( nullptr == handler->get_body() ); |
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433 | |
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434 | // Create new body. |
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435 | handler->set_body( new ReturnStmt( |
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436 | new ConstantExpr( Constant::from_int( index ) ) ) ); |
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437 | |
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438 | // Create the handler. |
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439 | body->push_back( create_single_matcher( except_obj, handler ) ); |
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440 | *it = nullptr; |
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441 | } |
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442 | |
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443 | body->push_back( new ReturnStmt( |
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444 | new ConstantExpr( Constant::from_int( 0 ) ) ) ); |
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445 | |
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446 | return new FunctionDecl("match", Type::StorageClasses(), |
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447 | LinkageSpec::Cforall, func_type, body); |
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448 | } |
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449 | |
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450 | CompoundStmt * TryMutatorCore::create_terminate_caller( |
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451 | FunctionDecl * try_wrapper, |
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452 | FunctionDecl * terminate_catch, |
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453 | FunctionDecl * terminate_match ) { |
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454 | // { __cfaehm_try_terminate(`try`, `catch`, `match`); } |
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455 | |
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456 | UntypedExpr * caller = new UntypedExpr( new NameExpr( |
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457 | "__cfaehm_try_terminate" ) ); |
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458 | std::list<Expression *>& args = caller->get_args(); |
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459 | args.push_back( nameOf( try_wrapper ) ); |
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460 | args.push_back( nameOf( terminate_catch ) ); |
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461 | args.push_back( nameOf( terminate_match ) ); |
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462 | |
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463 | CompoundStmt * callStmt = new CompoundStmt(); |
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464 | callStmt->push_back( new ExprStmt( caller ) ); |
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465 | return callStmt; |
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466 | } |
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467 | |
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468 | FunctionDecl * TryMutatorCore::create_resume_handler( |
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469 | CatchList &handlers ) { |
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470 | // bool handle(exception * except) { |
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471 | // HANDLER WRAPPERS { `hander->body`; return true; } |
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472 | // } |
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473 | CompoundStmt * body = new CompoundStmt(); |
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474 | |
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475 | FunctionType * func_type = handle_func_t.clone(); |
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476 | DeclarationWithType * except_obj = func_type->get_parameters().back(); |
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477 | |
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478 | CatchList::iterator it; |
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479 | for ( it = handlers.begin() ; it != handlers.end() ; ++it ) { |
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480 | CatchStmt * handler = *it; |
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481 | |
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482 | // Modifiy body. |
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483 | CompoundStmt * handling_code = |
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484 | dynamic_cast<CompoundStmt*>( handler->get_body() ); |
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485 | if ( ! handling_code ) { |
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486 | handling_code = new CompoundStmt(); |
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487 | handling_code->push_back( handler->get_body() ); |
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488 | } |
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489 | handling_code->push_back( new ReturnStmt( |
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490 | new ConstantExpr( Constant::from_bool( true ) ) ) ); |
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491 | handler->set_body( handling_code ); |
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492 | |
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493 | // Create the handler. |
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494 | body->push_back( create_single_matcher( except_obj, handler ) ); |
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495 | *it = nullptr; |
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496 | } |
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497 | |
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498 | body->push_back( new ReturnStmt( |
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499 | new ConstantExpr( Constant::from_bool( false ) ) ) ); |
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500 | |
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501 | return new FunctionDecl("handle", Type::StorageClasses(), |
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502 | LinkageSpec::Cforall, func_type, body); |
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503 | } |
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504 | |
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505 | CompoundStmt * TryMutatorCore::create_resume_wrapper( |
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506 | Statement * wraps, |
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507 | FunctionDecl * resume_handler ) { |
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508 | CompoundStmt * body = new CompoundStmt(); |
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509 | |
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510 | // struct __try_resume_node __resume_node |
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511 | // __attribute__((cleanup( __cfaehm_try_resume_cleanup ))); |
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512 | // ** unwinding of the stack here could cause problems ** |
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513 | // ** however I don't think that can happen currently ** |
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514 | // __cfaehm_try_resume_setup( &__resume_node, resume_handler ); |
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515 | |
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516 | std::list< Attribute * > attributes; |
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517 | { |
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518 | std::list< Expression * > attr_params; |
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519 | attr_params.push_back( new NameExpr( |
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520 | "__cfaehm_try_resume_cleanup" ) ); |
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521 | attributes.push_back( new Attribute( "cleanup", attr_params ) ); |
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522 | } |
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523 | |
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524 | ObjectDecl * obj = new ObjectDecl( |
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525 | "__resume_node", |
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526 | Type::StorageClasses(), |
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527 | LinkageSpec::Cforall, |
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528 | nullptr, |
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529 | new StructInstType( |
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530 | Type::Qualifiers(), |
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531 | node_decl |
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532 | ), |
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533 | nullptr, |
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534 | attributes |
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535 | ); |
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536 | appendDeclStmt( body, obj ); |
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537 | |
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538 | UntypedExpr *setup = new UntypedExpr( new NameExpr( |
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539 | "__cfaehm_try_resume_setup" ) ); |
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540 | setup->get_args().push_back( new AddressExpr( nameOf( obj ) ) ); |
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541 | setup->get_args().push_back( nameOf( resume_handler ) ); |
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542 | |
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543 | body->push_back( new ExprStmt( setup ) ); |
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544 | |
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545 | body->push_back( wraps ); |
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546 | return body; |
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547 | } |
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548 | |
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549 | FunctionDecl * TryMutatorCore::create_finally_wrapper( |
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550 | TryStmt * tryStmt ) { |
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551 | // void finally() { `finally->block` } |
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552 | FinallyStmt * finally = tryStmt->get_finally(); |
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553 | CompoundStmt * body = finally->get_block(); |
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554 | finally->set_block( nullptr ); |
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555 | delete finally; |
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556 | tryStmt->set_finally( nullptr ); |
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557 | |
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558 | return new FunctionDecl("finally", Type::StorageClasses(), |
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559 | LinkageSpec::Cforall, finally_func_t.clone(), body); |
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560 | } |
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561 | |
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562 | ObjectDecl * TryMutatorCore::create_finally_hook( |
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563 | FunctionDecl * finally_wrapper ) { |
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564 | // struct __cfaehm_cleanup_hook __finally_hook |
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565 | // __attribute__((cleanup( `finally_wrapper` ))); |
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566 | |
---|
567 | // Make Cleanup Attribute. |
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568 | std::list< Attribute * > attributes; |
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569 | { |
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570 | std::list< Expression * > attr_params; |
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571 | attr_params.push_back( nameOf( finally_wrapper ) ); |
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572 | attributes.push_back( new Attribute( "cleanup", attr_params ) ); |
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573 | } |
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574 | |
---|
575 | return new ObjectDecl( |
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576 | "__finally_hook", |
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577 | Type::StorageClasses(), |
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578 | LinkageSpec::Cforall, |
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579 | nullptr, |
---|
580 | new StructInstType( |
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581 | noQualifiers, |
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582 | hook_decl |
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583 | ), |
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584 | nullptr, |
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585 | attributes |
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586 | ); |
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587 | } |
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588 | |
---|
589 | Statement * TryMutatorCore::create_resume_rethrow( ThrowStmt *throwStmt ) { |
---|
590 | // return false; |
---|
591 | Statement * result = new ReturnStmt( |
---|
592 | new ConstantExpr( Constant::from_bool( false ) ) |
---|
593 | ); |
---|
594 | result->labels = throwStmt->labels; |
---|
595 | delete throwStmt; |
---|
596 | return result; |
---|
597 | } |
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598 | |
---|
599 | // Visiting/Mutating Functions |
---|
600 | void TryMutatorCore::premutate( StructDecl *structDecl ) { |
---|
601 | if ( !structDecl->has_body() ) { |
---|
602 | // Skip children? |
---|
603 | return; |
---|
604 | } else if ( structDecl->get_name() == "__cfaehm_base_exception_t" ) { |
---|
605 | assert( nullptr == except_decl ); |
---|
606 | except_decl = structDecl; |
---|
607 | init_func_types(); |
---|
608 | } else if ( structDecl->get_name() == "__cfaehm_try_resume_node" ) { |
---|
609 | assert( nullptr == node_decl ); |
---|
610 | node_decl = structDecl; |
---|
611 | } else if ( structDecl->get_name() == "__cfaehm_cleanup_hook" ) { |
---|
612 | assert( nullptr == hook_decl ); |
---|
613 | hook_decl = structDecl; |
---|
614 | } |
---|
615 | } |
---|
616 | |
---|
617 | Statement * TryMutatorCore::postmutate( TryStmt *tryStmt ) { |
---|
618 | assert( except_decl ); |
---|
619 | assert( node_decl ); |
---|
620 | assert( hook_decl ); |
---|
621 | |
---|
622 | // Generate a prefix for the function names? |
---|
623 | |
---|
624 | CompoundStmt * block = new CompoundStmt(); |
---|
625 | CompoundStmt * inner = take_try_block( tryStmt ); |
---|
626 | |
---|
627 | if ( tryStmt->get_finally() ) { |
---|
628 | // Define the helper function. |
---|
629 | FunctionDecl * finally_block = |
---|
630 | create_finally_wrapper( tryStmt ); |
---|
631 | appendDeclStmt( block, finally_block ); |
---|
632 | // Create and add the finally cleanup hook. |
---|
633 | appendDeclStmt( block, create_finally_hook( finally_block ) ); |
---|
634 | } |
---|
635 | |
---|
636 | CatchList termination_handlers; |
---|
637 | CatchList resumption_handlers; |
---|
638 | split( tryStmt->get_catchers(), |
---|
639 | termination_handlers, resumption_handlers ); |
---|
640 | |
---|
641 | if ( resumption_handlers.size() ) { |
---|
642 | // Define the helper function. |
---|
643 | FunctionDecl * resume_handler = |
---|
644 | create_resume_handler( resumption_handlers ); |
---|
645 | appendDeclStmt( block, resume_handler ); |
---|
646 | // Prepare hooks |
---|
647 | inner = create_resume_wrapper( inner, resume_handler ); |
---|
648 | } |
---|
649 | |
---|
650 | if ( termination_handlers.size() ) { |
---|
651 | // Define the three helper functions. |
---|
652 | FunctionDecl * try_wrapper = create_try_wrapper( inner ); |
---|
653 | appendDeclStmt( block, try_wrapper ); |
---|
654 | FunctionDecl * terminate_catch = |
---|
655 | create_terminate_catch( termination_handlers ); |
---|
656 | appendDeclStmt( block, terminate_catch ); |
---|
657 | FunctionDecl * terminate_match = |
---|
658 | create_terminate_match( termination_handlers ); |
---|
659 | appendDeclStmt( block, terminate_match ); |
---|
660 | // Build the call to the try wrapper. |
---|
661 | inner = create_terminate_caller( |
---|
662 | try_wrapper, terminate_catch, terminate_match ); |
---|
663 | } |
---|
664 | |
---|
665 | // Embed the try block. |
---|
666 | block->push_back( inner ); |
---|
667 | |
---|
668 | return block; |
---|
669 | } |
---|
670 | |
---|
671 | Statement * TryMutatorCore::postmutate( ThrowStmt *throwStmt ) { |
---|
672 | // Only valid `throwResume;` statements should remain. (2/3 checks) |
---|
673 | assert( ThrowStmt::Resume == throwStmt->kind && ! throwStmt->expr ); |
---|
674 | return create_resume_rethrow( throwStmt ); |
---|
675 | } |
---|
676 | |
---|
677 | void translateThrows( std::list< Declaration *> & translationUnit ) { |
---|
678 | PassVisitor<ThrowMutatorCore> translator; |
---|
679 | mutateAll( translationUnit, translator ); |
---|
680 | } |
---|
681 | |
---|
682 | void translateTries( std::list< Declaration *> & translationUnit ) { |
---|
683 | PassVisitor<TryMutatorCore> translator; |
---|
684 | mutateAll( translationUnit, translator ); |
---|
685 | } |
---|
686 | } |
---|