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src/ControlStruct/MultiLevelExit.cpp (modified) (25 diffs)
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src/ControlStruct/MultiLevelExit.cpp
r66daee4 rcb921d4 9 9 // Author : Andrew Beach 10 10 // Created On : Mon Nov 1 13:48:00 2021 11 // Last Modified By : Peter A. Buhr12 // Last Modified On : Mon Jan 31 22:35:08 202213 // Update Count : 2 811 // Last Modified By : Andrew Beach 12 // Last Modified On : Mon Nov 8 10:56:00 2021 13 // Update Count : 2 14 14 // 15 15 … … 18 18 #include "AST/Pass.hpp" 19 19 #include "AST/Stmt.hpp" 20 #include " LabelGeneratorNew.hpp"20 #include "ControlStruct/LabelGenerator.h" 21 21 22 22 #include <set> 23 using namespace std;24 using namespace ast;25 23 26 24 namespace ControlStruct { 25 26 namespace { 27 27 28 class Entry { 28 public:29 const Stmt * stmt;30 private:29 public: 30 const ast::Stmt * stmt; 31 private: 31 32 // Organized like a manual ADT. Avoids creating a bunch of dead data. 32 33 struct Target { 33 Label label;34 ast::Label label; 34 35 bool used = false; 35 Target( const Label & label ) : label( label ) {}36 Target( const ast::Label & label ) : label( label ) {} 36 37 Target() : label( CodeLocation() ) {} 37 38 }; … … 40 41 41 42 enum Kind { 42 ForStmt K, WhileStmtK, CompoundStmtK, IfStmtK, CaseStmtK, SwitchStmtK, TryStmtK43 ForStmt, WhileStmt, CompoundStmt, IfStmt, CaseStmt, SwitchStmt, TryStmt 43 44 } kind; 44 45 45 46 bool fallDefaultValid = true; 46 47 47 static Label & useTarget( Target & target ) {48 static ast::Label & useTarget( Target & target ) { 48 49 target.used = true; 49 50 return target.label; 50 51 } 51 52 52 public:53 Entry( const ForStmt * stmt, Label breakExit,Label contExit ) :54 stmt( stmt ), firstTarget( breakExit ), secondTarget( contExit ), kind( ForStmt K) {}55 Entry( const WhileStmt * stmt, Label breakExit,Label contExit ) :56 stmt( stmt ), firstTarget( breakExit ), secondTarget( contExit ), kind( WhileStmt K) {}57 Entry( const CompoundStmt *stmt,Label breakExit ) :58 stmt( stmt ), firstTarget( breakExit ), secondTarget(), kind( CompoundStmt K) {}59 Entry( const IfStmt *stmt,Label breakExit ) :60 stmt( stmt ), firstTarget( breakExit ), secondTarget(), kind( IfStmt K) {}61 Entry( const CaseStmt *stmt,Label fallExit ) :62 stmt( stmt ), firstTarget( fallExit ), secondTarget(), kind( CaseStmt K) {}63 Entry( const SwitchStmt *stmt, Label breakExit,Label fallDefaultExit ) :64 stmt( stmt ), firstTarget( breakExit ), secondTarget( fallDefaultExit ), kind( SwitchStmt K) {}65 Entry( const TryStmt *stmt,Label breakExit ) :66 stmt( stmt ), firstTarget( breakExit ), secondTarget(), kind( TryStmt K) {}67 68 bool isContTarget() const { return kind <= WhileStmt K; }69 bool isBreakTarget() const { return kind != CaseStmtK; }70 bool isFallTarget() const { return kind == CaseStmtK; }71 bool isFallDefaultTarget() const { return kind == SwitchStmtK; }72 73 Label useContExit() { assert( kind <= WhileStmtK); return useTarget(secondTarget); }74 Label useBreakExit() { assert( kind != CaseStmtK); return useTarget(firstTarget); }75 Label useFallExit() { assert( kind == CaseStmtK); return useTarget(firstTarget); }76 Label useFallDefaultExit() { assert( kind == SwitchStmtK); return useTarget(secondTarget); }77 78 bool isContUsed() const { assert( kind <= WhileStmt K); return secondTarget.used; }79 bool isBreakUsed() const { assert( kind != CaseStmtK); return firstTarget.used; }80 bool isFallUsed() const { assert( kind == CaseStmtK); return firstTarget.used; }81 bool isFallDefaultUsed() const { assert( kind == SwitchStmtK); return secondTarget.used; }53 public: 54 Entry( const ast::ForStmt * stmt, ast::Label breakExit, ast::Label contExit ) : 55 stmt( stmt ), firstTarget( breakExit ), secondTarget( contExit ), kind( ForStmt ) {} 56 Entry( const ast::WhileStmt * stmt, ast::Label breakExit, ast::Label contExit ) : 57 stmt( stmt ), firstTarget( breakExit ), secondTarget( contExit ), kind( WhileStmt ) {} 58 Entry( const ast::CompoundStmt *stmt, ast::Label breakExit ) : 59 stmt( stmt ), firstTarget( breakExit ), secondTarget(), kind( CompoundStmt ) {} 60 Entry( const ast::IfStmt *stmt, ast::Label breakExit ) : 61 stmt( stmt ), firstTarget( breakExit ), secondTarget(), kind( IfStmt ) {} 62 Entry( const ast::CaseStmt *stmt, ast::Label fallExit ) : 63 stmt( stmt ), firstTarget( fallExit ), secondTarget(), kind( CaseStmt ) {} 64 Entry( const ast::SwitchStmt *stmt, ast::Label breakExit, ast::Label fallDefaultExit ) : 65 stmt( stmt ), firstTarget( breakExit ), secondTarget( fallDefaultExit ), kind( SwitchStmt ) {} 66 Entry( const ast::TryStmt *stmt, ast::Label breakExit ) : 67 stmt( stmt ), firstTarget( breakExit ), secondTarget(), kind( TryStmt ) {} 68 69 bool isContTarget() const { return kind <= WhileStmt; } 70 bool isBreakTarget() const { return CaseStmt != kind; } 71 bool isFallTarget() const { return CaseStmt == kind; } 72 bool isFallDefaultTarget() const { return SwitchStmt == kind; } 73 74 ast::Label useContExit() { assert( kind <= WhileStmt ); return useTarget(secondTarget); } 75 ast::Label useBreakExit() { assert( CaseStmt != kind ); return useTarget(firstTarget); } 76 ast::Label useFallExit() { assert( CaseStmt == kind ); return useTarget(firstTarget); } 77 ast::Label useFallDefaultExit() { assert( SwitchStmt == kind ); return useTarget(secondTarget); } 78 79 bool isContUsed() const { assert( kind <= WhileStmt ); return secondTarget.used; } 80 bool isBreakUsed() const { assert( CaseStmt != kind ); return firstTarget.used; } 81 bool isFallUsed() const { assert( CaseStmt == kind ); return firstTarget.used; } 82 bool isFallDefaultUsed() const { assert( SwitchStmt == kind ); return secondTarget.used; } 82 83 void seenDefault() { fallDefaultValid = false; } 83 84 bool isFallDefaultValid() const { return fallDefaultValid; } 84 85 }; 85 86 86 // Helper predicates used in find_if calls (it doesn't take methods):87 // Helper predicates used in std::find_if calls (it doesn't take methods): 87 88 bool isBreakTarget( const Entry & entry ) { 88 89 return entry.isBreakTarget(); … … 102 103 103 104 struct MultiLevelExitCore final : 104 publicWithVisitorRef<MultiLevelExitCore>,105 public WithShortCircuiting, publicWithGuards {105 public ast::WithVisitorRef<MultiLevelExitCore>, 106 public ast::WithShortCircuiting, public ast::WithGuards { 106 107 MultiLevelExitCore( const LabelToStmt & lt ); 107 108 108 void previsit( const FunctionDecl * );109 110 const CompoundStmt * previsit( constCompoundStmt * );111 const BranchStmt * postvisit( constBranchStmt * );112 void previsit( const WhileStmt * );113 const WhileStmt * postvisit( constWhileStmt * );114 void previsit( const ForStmt * );115 const ForStmt * postvisit( constForStmt * );116 const CaseStmt * previsit( constCaseStmt * );117 void previsit( const IfStmt * );118 const IfStmt * postvisit( constIfStmt * );119 void previsit( const SwitchStmt * );120 const SwitchStmt * postvisit( constSwitchStmt * );121 void previsit( const ReturnStmt * );122 void previsit( const TryStmt * );123 void postvisit( const TryStmt * );124 void previsit( const FinallyStmt * );125 126 const Stmt * mutateLoop( constStmt * body, Entry& );109 void previsit( const ast::FunctionDecl * ); 110 111 const ast::CompoundStmt * previsit( const ast::CompoundStmt * ); 112 const ast::BranchStmt * postvisit( const ast::BranchStmt * ); 113 void previsit( const ast::WhileStmt * ); 114 const ast::WhileStmt * postvisit( const ast::WhileStmt * ); 115 void previsit( const ast::ForStmt * ); 116 const ast::ForStmt * postvisit( const ast::ForStmt * ); 117 const ast::CaseStmt * previsit( const ast::CaseStmt * ); 118 void previsit( const ast::IfStmt * ); 119 const ast::IfStmt * postvisit( const ast::IfStmt * ); 120 void previsit( const ast::SwitchStmt * ); 121 const ast::SwitchStmt * postvisit( const ast::SwitchStmt * ); 122 void previsit( const ast::ReturnStmt * ); 123 void previsit( const ast::TryStmt * ); 124 void postvisit( const ast::TryStmt * ); 125 void previsit( const ast::FinallyStmt * ); 126 127 const ast::Stmt * mutateLoop( const ast::Stmt * body, Entry& ); 127 128 128 129 const LabelToStmt & target_table; 129 s et<Label> fallthrough_labels;130 vector<Entry> enclosing_control_structures;131 Label break_label;130 std::set<ast::Label> fallthrough_labels; 131 std::vector<Entry> enclosing_control_structures; 132 ast::Label break_label; 132 133 bool inFinally; 133 134 … … 137 138 const LoopNode * posthandleLoopStmt( const LoopNode * loopStmt ); 138 139 139 list<ptr<Stmt>> fixBlock(140 const list<ptr<Stmt>> & kids, bool caseClause );140 std::list<ast::ptr<ast::Stmt>> fixBlock( 141 const std::list<ast::ptr<ast::Stmt>> & kids, bool caseClause ); 141 142 142 143 template<typename UnaryPredicate> 143 144 auto findEnclosingControlStructure( UnaryPredicate pred ) { 144 return find_if( enclosing_control_structures.rbegin(),145 enclosing_control_structures.rend(), pred );145 return std::find_if( enclosing_control_structures.rbegin(), 146 enclosing_control_structures.rend(), pred ); 146 147 } 147 148 }; 148 149 149 NullStmt * labelledNullStmt(150 const CodeLocation & cl, constLabel & label ) {151 return new NullStmt( cl, vector<Label>{ label } );150 ast::NullStmt * labelledNullStmt( 151 const CodeLocation & cl, const ast::Label & label ) { 152 return new ast::NullStmt( cl, std::vector<ast::Label>{ label } ); 152 153 } 153 154 … … 157 158 {} 158 159 159 void MultiLevelExitCore::previsit( const FunctionDecl * ) {160 void MultiLevelExitCore::previsit( const ast::FunctionDecl * ) { 160 161 visit_children = false; 161 162 } 162 163 163 const CompoundStmt * MultiLevelExitCore::previsit(164 constCompoundStmt * stmt ) {164 const ast::CompoundStmt * MultiLevelExitCore::previsit( 165 const ast::CompoundStmt * stmt ) { 165 166 visit_children = false; 166 167 bool isLabeled = !stmt->labels.empty(); 167 168 if ( isLabeled ) { 168 Label breakLabel =newLabel( "blockBreak", stmt );169 ast::Label breakLabel = LabelGenerator::newLabel( "blockBreak", stmt ); 169 170 enclosing_control_structures.emplace_back( stmt, breakLabel ); 170 171 GuardAction( [this]() { enclosing_control_structures.pop_back(); } ); 171 172 } 172 173 173 auto mutStmt = mutate( stmt );174 auto mutStmt = ast::mutate( stmt ); 174 175 // A child statement may set the break label. 175 mutStmt->kids = move( fixBlock( stmt->kids, false ) );176 mutStmt->kids = std::move( fixBlock( stmt->kids, false ) ); 176 177 177 178 if ( isLabeled ) { … … 186 187 187 188 size_t getUnusedIndex( 188 const Stmt * stmt, constLabel & originalTarget ) {189 const ast::Stmt * stmt, const ast::Label & originalTarget ) { 189 190 const size_t size = stmt->labels.size(); 190 191 191 // If the label is empty, do not add unused attribute.192 if ( originalTarget.empty() ) return size;192 // If the label is empty, we can skip adding the unused attribute: 193 if ( originalTarget.empty() ) return size; 193 194 194 195 // Search for a label that matches the originalTarget. 195 196 for ( size_t i = 0 ; i < size ; ++i ) { 196 const Label & label = stmt->labels[i];197 const ast::Label & label = stmt->labels[i]; 197 198 if ( label == originalTarget ) { 198 for ( const Attribute * attr : label.attributes ) {199 for ( const ast::Attribute * attr : label.attributes ) { 199 200 if ( attr->name == "unused" ) return size; 200 201 } … … 203 204 } 204 205 assertf( false, "Could not find label '%s' on statement %s", 205 originalTarget.name.c_str(), toString( stmt ).c_str() );206 } 207 208 const Stmt * addUnused(209 const Stmt * stmt, constLabel & originalTarget ) {206 originalTarget.name.c_str(), toString( stmt ).c_str() ); 207 } 208 209 const ast::Stmt * addUnused( 210 const ast::Stmt * stmt, const ast::Label & originalTarget ) { 210 211 size_t i = getUnusedIndex( stmt, originalTarget ); 211 212 if ( i == stmt->labels.size() ) { 212 213 return stmt; 213 214 } 214 Stmt * mutStmt =mutate( stmt );215 mutStmt->labels[i].attributes.push_back( new Attribute( "unused" ) );215 ast::Stmt * mutStmt = ast::mutate( stmt ); 216 mutStmt->labels[i].attributes.push_back( new ast::Attribute( "unused" ) ); 216 217 return mutStmt; 217 218 } 218 219 219 const BranchStmt * MultiLevelExitCore::postvisit( constBranchStmt * stmt ) {220 vector<Entry>::reverse_iterator targetEntry =220 const ast::BranchStmt * MultiLevelExitCore::postvisit( const ast::BranchStmt * stmt ) { 221 std::vector<Entry>::reverse_iterator targetEntry = 221 222 enclosing_control_structures.rend(); 222 223 switch ( stmt->kind ) { 223 caseBranchStmt::Goto:224 case ast::BranchStmt::Goto: 224 225 return stmt; 225 case BranchStmt::Continue: 226 case BranchStmt::Break: { 227 bool isContinue = stmt->kind == BranchStmt::Continue; 228 // Handle unlabeled break and continue. 229 if ( stmt->target.empty() ) { 230 if ( isContinue ) { 231 targetEntry = findEnclosingControlStructure( isContinueTarget ); 232 } else { 233 if ( enclosing_control_structures.empty() ) { 234 SemanticError( stmt->location, 235 "'break' outside a loop, 'switch', or labelled block" ); 236 } 237 targetEntry = findEnclosingControlStructure( isBreakTarget ); 238 } 239 // Handle labeled break and continue. 240 } else { 241 // Lookup label in table to find attached control structure. 242 targetEntry = findEnclosingControlStructure( 243 [ targetStmt = target_table.at(stmt->target) ](auto entry){ 244 return entry.stmt == targetStmt; 245 } ); 246 } 247 // Ensure that selected target is valid. 248 if ( targetEntry == enclosing_control_structures.rend() || ( isContinue && !isContinueTarget( *targetEntry ) ) ) { 249 SemanticError( stmt->location, toString( (isContinue ? "'continue'" : "'break'"), 250 " target must be an enclosing ", (isContinue ? "loop: " : "control structure: "), 251 stmt->originalTarget ) ); 252 } 253 break; 254 } 255 case BranchStmt::FallThrough: { 256 targetEntry = findEnclosingControlStructure( isFallthroughTarget ); 257 // Check that target is valid. 258 if ( targetEntry == enclosing_control_structures.rend() ) { 259 SemanticError( stmt->location, "'fallthrough' must be enclosed in a 'switch' or 'choose'" ); 260 } 261 if ( !stmt->target.empty() ) { 262 // Labelled fallthrough: target must be a valid fallthough label. 263 if ( !fallthrough_labels.count( stmt->target ) ) { 264 SemanticError( stmt->location, toString( "'fallthrough' target must be a later case statement: ", 265 stmt->originalTarget ) ); 266 } 267 return new BranchStmt( 268 stmt->location, BranchStmt::Goto, stmt->originalTarget ); 269 } 270 break; 271 } 272 case BranchStmt::FallThroughDefault: { 273 targetEntry = findEnclosingControlStructure( isFallthroughDefaultTarget ); 274 275 // Check if in switch or choose statement. 276 if ( targetEntry == enclosing_control_structures.rend() ) { 277 SemanticError( stmt->location, "'fallthrough' must be enclosed in a 'switch' or 'choose'" ); 278 } 279 280 // Check if switch or choose has default clause. 281 auto switchStmt = strict_dynamic_cast< const SwitchStmt * >( targetEntry->stmt ); 282 bool foundDefault = false; 283 for ( auto subStmt : switchStmt->stmts ) { 284 const CaseStmt * caseStmt = subStmt.strict_as<CaseStmt>(); 285 if ( caseStmt->isDefault() ) { 286 foundDefault = true; 287 break; 288 } 289 } 290 if ( ! foundDefault ) { 291 SemanticError( stmt->location, "'fallthrough default' must be enclosed in a 'switch' or 'choose'" 292 "control structure with a 'default' clause" ); 293 } 294 break; 295 } 296 default: 226 case ast::BranchStmt::Continue: 227 case ast::BranchStmt::Break: { 228 bool isContinue = stmt->kind == ast::BranchStmt::Continue; 229 // Handle unlabeled break and continue. 230 if ( stmt->target.empty() ) { 231 if ( isContinue ) { 232 targetEntry = findEnclosingControlStructure( isContinueTarget ); 233 } else { 234 if ( enclosing_control_structures.empty() ) { 235 SemanticError( stmt->location, 236 "'break' outside a loop, 'switch', or labelled block" ); 237 } 238 targetEntry = findEnclosingControlStructure( isBreakTarget ); 239 } 240 // Handle labeled break and continue. 241 } else { 242 // Lookup label in table to find attached control structure. 243 targetEntry = findEnclosingControlStructure( 244 [ targetStmt = target_table.at(stmt->target) ](auto entry){ 245 return entry.stmt == targetStmt; 246 } ); 247 } 248 // Ensure that selected target is valid. 249 if ( targetEntry == enclosing_control_structures.rend() || ( isContinue && !isContinueTarget( *targetEntry ) ) ) { 250 SemanticError( 251 stmt->location, 252 toString( (isContinue ? "'continue'" : "'break'"), 253 " target must be an enclosing ", 254 (isContinue ? "loop: " : "control structure: "), 255 stmt->originalTarget ) ); 256 } 257 break; 258 } 259 case ast::BranchStmt::FallThrough: { 260 targetEntry = findEnclosingControlStructure( isFallthroughTarget ); 261 // Check that target is valid. 262 if ( targetEntry == enclosing_control_structures.rend() ) { 263 SemanticError( stmt->location, "'fallthrough' must be enclosed in a 'switch' or 'choose'" ); 264 } 265 if ( !stmt->target.empty() ) { 266 // Labelled fallthrough: target must be a valid fallthough label. 267 if ( !fallthrough_labels.count( stmt->target ) ) { 268 SemanticError( stmt->location, toString( "'fallthrough' target must be a later case statement: ", stmt->originalTarget ) ); 269 } 270 return new ast::BranchStmt( 271 stmt->location, ast::BranchStmt::Goto, stmt->originalTarget ); 272 } 273 break; 274 } 275 case ast::BranchStmt::FallThroughDefault: { 276 targetEntry = findEnclosingControlStructure( isFallthroughDefaultTarget ); 277 278 // Check that this is in a switch or choose statement. 279 if ( targetEntry == enclosing_control_structures.rend() ) { 280 SemanticError( stmt->location, "'fallthrough' must be enclosed in a 'switch' or 'choose'" ); 281 } 282 283 // Check that the switch or choose has a default clause. 284 auto switchStmt = strict_dynamic_cast< const ast::SwitchStmt * >( 285 targetEntry->stmt ); 286 bool foundDefault = false; 287 for ( auto subStmt : switchStmt->stmts ) { 288 const ast::CaseStmt * caseStmt = subStmt.strict_as<ast::CaseStmt>(); 289 if ( caseStmt->isDefault() ) { 290 foundDefault = true; 291 break; 292 } 293 } 294 if ( !foundDefault ) { 295 SemanticError( stmt->location, "'fallthrough default' must be enclosed in a 'switch' or 'choose' control structure with a 'default' clause" ); 296 } 297 break; 298 } 299 default: 297 300 assert( false ); 298 301 } 299 302 300 303 // Branch error checks: get the appropriate label name: 301 // (This label is alwaysreplaced.)302 Label exitLabel( CodeLocation(), "" );304 // (This label will always be replaced.) 305 ast::Label exitLabel( CodeLocation(), "" ); 303 306 switch ( stmt->kind ) { 304 caseBranchStmt::Break:307 case ast::BranchStmt::Break: 305 308 assert( !targetEntry->useBreakExit().empty() ); 306 309 exitLabel = targetEntry->useBreakExit(); 307 310 break; 308 caseBranchStmt::Continue:311 case ast::BranchStmt::Continue: 309 312 assert( !targetEntry->useContExit().empty() ); 310 313 exitLabel = targetEntry->useContExit(); 311 314 break; 312 caseBranchStmt::FallThrough:315 case ast::BranchStmt::FallThrough: 313 316 assert( !targetEntry->useFallExit().empty() ); 314 317 exitLabel = targetEntry->useFallExit(); 315 318 break; 316 caseBranchStmt::FallThroughDefault:319 case ast::BranchStmt::FallThroughDefault: 317 320 assert( !targetEntry->useFallDefaultExit().empty() ); 318 321 exitLabel = targetEntry->useFallDefaultExit(); 319 322 // Check that fallthrough default comes before the default clause. 320 323 if ( !targetEntry->isFallDefaultValid() ) { 321 SemanticError( stmt->location, "'fallthrough default' must precede the 'default' clause" ); 324 SemanticError( stmt->location, 325 "'fallthrough default' must precede the 'default' clause" ); 322 326 } 323 327 break; 324 default:328 default: 325 329 assert(0); 326 330 } … … 329 333 targetEntry->stmt = addUnused( targetEntry->stmt, stmt->originalTarget ); 330 334 331 // Replace withgoto to make later passes more uniform.332 return new BranchStmt( stmt->location,BranchStmt::Goto, exitLabel );333 } 334 335 void MultiLevelExitCore::previsit( const WhileStmt * stmt ) {335 // Replace this with a goto to make later passes more uniform. 336 return new ast::BranchStmt( stmt->location, ast::BranchStmt::Goto, exitLabel ); 337 } 338 339 void MultiLevelExitCore::previsit( const ast::WhileStmt * stmt ) { 336 340 return prehandleLoopStmt( stmt ); 337 341 } 338 342 339 const WhileStmt * MultiLevelExitCore::postvisit( constWhileStmt * stmt ) {343 const ast::WhileStmt * MultiLevelExitCore::postvisit( const ast::WhileStmt * stmt ) { 340 344 return posthandleLoopStmt( stmt ); 341 345 } 342 346 343 void MultiLevelExitCore::previsit( const ForStmt * stmt ) {347 void MultiLevelExitCore::previsit( const ast::ForStmt * stmt ) { 344 348 return prehandleLoopStmt( stmt ); 345 349 } 346 350 347 const ForStmt * MultiLevelExitCore::postvisit( constForStmt * stmt ) {351 const ast::ForStmt * MultiLevelExitCore::postvisit( const ast::ForStmt * stmt ) { 348 352 return posthandleLoopStmt( stmt ); 349 353 } … … 351 355 // Mimic what the built-in push_front would do anyways. It is O(n). 352 356 void push_front( 353 vector<ptr<Stmt>> & vec, constStmt * element ) {357 std::vector<ast::ptr<ast::Stmt>> & vec, const ast::Stmt * element ) { 354 358 vec.emplace_back( nullptr ); 355 359 for ( size_t i = vec.size() - 1 ; 0 < i ; --i ) { 356 vec[ i ] = move( vec[ i - 1 ] );360 vec[ i ] = std::move( vec[ i - 1 ] ); 357 361 } 358 362 vec[ 0 ] = element; 359 363 } 360 364 361 const CaseStmt * MultiLevelExitCore::previsit( constCaseStmt * stmt ) {365 const ast::CaseStmt * MultiLevelExitCore::previsit( const ast::CaseStmt * stmt ) { 362 366 visit_children = false; 363 367 364 // If default, markseen.368 // If it is the default, mark the default as seen. 365 369 if ( stmt->isDefault() ) { 366 370 assert( !enclosing_control_structures.empty() ); … … 369 373 370 374 // The cond may not exist, but if it does update it now. 371 visitor->maybe_accept( stmt, & CaseStmt::cond );375 visitor->maybe_accept( stmt, &ast::CaseStmt::cond ); 372 376 373 377 // Just save the mutated node for simplicity. 374 CaseStmt * mutStmt =mutate( stmt );375 376 Label fallLabel =newLabel( "fallThrough", stmt );377 if ( ! mutStmt->stmts.empty() ) {378 ast::CaseStmt * mutStmt = ast::mutate( stmt ); 379 380 ast::Label fallLabel = LabelGenerator::newLabel( "fallThrough", stmt ); 381 if ( !mutStmt->stmts.empty() ) { 378 382 // Ensure that the stack isn't corrupted by exceptions in fixBlock. 379 383 auto guard = makeFuncGuard( 380 384 [&](){ enclosing_control_structures.emplace_back( mutStmt, fallLabel ); }, 381 385 [this](){ enclosing_control_structures.pop_back(); } 382 );386 ); 383 387 384 388 // These should already be in a block. 385 auto block = mutate( mutStmt->stmts.front().strict_as<CompoundStmt>() );389 auto block = ast::mutate( mutStmt->stmts.front().strict_as<ast::CompoundStmt>() ); 386 390 block->kids = fixBlock( block->kids, true ); 387 391 388 392 // Add fallthrough label if necessary. 389 assert( ! enclosing_control_structures.empty() );393 assert( !enclosing_control_structures.empty() ); 390 394 Entry & entry = enclosing_control_structures.back(); 391 395 if ( entry.isFallUsed() ) { … … 394 398 } 395 399 } 396 assert( ! enclosing_control_structures.empty() );400 assert( !enclosing_control_structures.empty() ); 397 401 Entry & entry = enclosing_control_structures.back(); 398 assertf( dynamic_cast< const SwitchStmt * >( entry.stmt ),399 "Control structure enclosing a case clause must be a switch, but is: %s",400 toString( entry.stmt ).c_str() );402 assertf( dynamic_cast< const ast::SwitchStmt * >( entry.stmt ), 403 "Control structure enclosing a case clause must be a switch, but is: %s", 404 toString( entry.stmt ).c_str() ); 401 405 if ( mutStmt->isDefault() ) { 402 406 if ( entry.isFallDefaultUsed() ) { 403 407 // Add fallthrough default label if necessary. 404 408 push_front( mutStmt->stmts, labelledNullStmt( 405 stmt->location, entry.useFallDefaultExit()406 ) );409 stmt->location, entry.useFallDefaultExit() 410 ) ); 407 411 } 408 412 } … … 410 414 } 411 415 412 void MultiLevelExitCore::previsit( const IfStmt * stmt ) {416 void MultiLevelExitCore::previsit( const ast::IfStmt * stmt ) { 413 417 bool labeledBlock = !stmt->labels.empty(); 414 418 if ( labeledBlock ) { 415 Label breakLabel =newLabel( "blockBreak", stmt );419 ast::Label breakLabel = LabelGenerator::newLabel( "blockBreak", stmt ); 416 420 enclosing_control_structures.emplace_back( stmt, breakLabel ); 417 421 GuardAction( [this](){ enclosing_control_structures.pop_back(); } ); … … 419 423 } 420 424 421 const IfStmt * MultiLevelExitCore::postvisit( constIfStmt * stmt ) {425 const ast::IfStmt * MultiLevelExitCore::postvisit( const ast::IfStmt * stmt ) { 422 426 bool labeledBlock = !stmt->labels.empty(); 423 427 if ( labeledBlock ) { … … 430 434 } 431 435 432 bool isDefaultCase( const ptr<Stmt> & stmt ) {433 const CaseStmt * caseStmt = stmt.strict_as<CaseStmt>();436 bool isDefaultCase( const ast::ptr<ast::Stmt> & stmt ) { 437 const ast::CaseStmt * caseStmt = stmt.strict_as<ast::CaseStmt>(); 434 438 return caseStmt->isDefault(); 435 439 } 436 440 437 void MultiLevelExitCore::previsit( const SwitchStmt * stmt ) {438 Label label =newLabel( "switchBreak", stmt );439 auto it = find_if( stmt->stmts.rbegin(), stmt->stmts.rend(), isDefaultCase );440 441 const CaseStmt * defaultCase = it != stmt->stmts.rend()442 ? (it)->strict_as< CaseStmt>() : nullptr;443 Label defaultLabel = defaultCase444 ? newLabel( "fallThroughDefault", defaultCase )445 : Label( stmt->location, "" );441 void MultiLevelExitCore::previsit( const ast::SwitchStmt * stmt ) { 442 ast::Label label = LabelGenerator::newLabel( "switchBreak", stmt ); 443 auto it = std::find_if( stmt->stmts.rbegin(), stmt->stmts.rend(), isDefaultCase ); 444 445 const ast::CaseStmt * defaultCase = it != stmt->stmts.rend() 446 ? (it)->strict_as<ast::CaseStmt>() : nullptr; 447 ast::Label defaultLabel = defaultCase 448 ? LabelGenerator::newLabel( "fallThroughDefault", defaultCase ) 449 : ast::Label( stmt->location, "" ); 446 450 enclosing_control_structures.emplace_back( stmt, label, defaultLabel ); 447 451 GuardAction( [this]() { enclosing_control_structures.pop_back(); } ); 448 452 449 453 // Collect valid labels for fallthrough. It starts with all labels at 450 // this level, then remove as each is seen duringtraversal.451 for ( const Stmt * stmt : stmt->stmts ) {452 auto * caseStmt = strict_dynamic_cast< const CaseStmt * >( stmt );454 // this level, then removed as we see them in traversal. 455 for ( const ast::Stmt * stmt : stmt->stmts ) { 456 auto * caseStmt = strict_dynamic_cast< const ast::CaseStmt * >( stmt ); 453 457 if ( caseStmt->stmts.empty() ) continue; 454 auto block = caseStmt->stmts.front().strict_as< CompoundStmt>();455 for ( const Stmt * stmt : block->kids ) {456 for ( const Label & l : stmt->labels ) {458 auto block = caseStmt->stmts.front().strict_as<ast::CompoundStmt>(); 459 for ( const ast::Stmt * stmt : block->kids ) { 460 for ( const ast::Label & l : stmt->labels ) { 457 461 fallthrough_labels.insert( l ); 458 462 } … … 461 465 } 462 466 463 const SwitchStmt * MultiLevelExitCore::postvisit( constSwitchStmt * stmt ) {467 const ast::SwitchStmt * MultiLevelExitCore::postvisit( const ast::SwitchStmt * stmt ) { 464 468 assert( !enclosing_control_structures.empty() ); 465 469 Entry & entry = enclosing_control_structures.back(); 466 470 assert( entry.stmt == stmt ); 467 471 468 // Only run to generate the break label.472 // Only run if we need to generate the break label. 469 473 if ( entry.isBreakUsed() ) { 470 474 // To keep the switch statements uniform (all direct children of a 471 475 // SwitchStmt should be CastStmts), append the exit label and break 472 476 // to the last case, create a default case is there are no cases. 473 SwitchStmt * mutStmt =mutate( stmt );477 ast::SwitchStmt * mutStmt = ast::mutate( stmt ); 474 478 if ( mutStmt->stmts.empty() ) { 475 mutStmt->stmts.push_back( new CaseStmt(476 mutStmt->location, nullptr, {} ));477 } 478 479 auto caseStmt = mutStmt->stmts.back().strict_as< CaseStmt>();480 auto mutCase = mutate( caseStmt );479 mutStmt->stmts.push_back( new ast::CaseStmt( 480 mutStmt->location, nullptr, {} )); 481 } 482 483 auto caseStmt = mutStmt->stmts.back().strict_as<ast::CaseStmt>(); 484 auto mutCase = ast::mutate( caseStmt ); 481 485 mutStmt->stmts.back() = mutCase; 482 486 483 Label label( mutCase->location, "breakLabel" );484 auto branch = new BranchStmt( mutCase->location,BranchStmt::Break, label );487 ast::Label label( mutCase->location, "breakLabel" ); 488 auto branch = new ast::BranchStmt( mutCase->location, ast::BranchStmt::Break, label ); 485 489 branch->labels.push_back( entry.useBreakExit() ); 486 490 mutCase->stmts.push_back( branch ); … … 491 495 } 492 496 493 void MultiLevelExitCore::previsit( const ReturnStmt * stmt ) {497 void MultiLevelExitCore::previsit( const ast::ReturnStmt * stmt ) { 494 498 if ( inFinally ) { 495 499 SemanticError( stmt->location, "'return' may not appear in a finally clause" ); … … 497 501 } 498 502 499 void MultiLevelExitCore::previsit( const TryStmt * stmt ) {503 void MultiLevelExitCore::previsit( const ast::TryStmt * stmt ) { 500 504 bool isLabeled = !stmt->labels.empty(); 501 505 if ( isLabeled ) { 502 Label breakLabel =newLabel( "blockBreak", stmt );506 ast::Label breakLabel = LabelGenerator::newLabel( "blockBreak", stmt ); 503 507 enclosing_control_structures.emplace_back( stmt, breakLabel ); 504 508 GuardAction([this](){ enclosing_control_structures.pop_back(); } ); … … 506 510 } 507 511 508 void MultiLevelExitCore::postvisit( const TryStmt * stmt ) {512 void MultiLevelExitCore::postvisit( const ast::TryStmt * stmt ) { 509 513 bool isLabeled = !stmt->labels.empty(); 510 514 if ( isLabeled ) { … … 516 520 } 517 521 518 void MultiLevelExitCore::previsit( const FinallyStmt * ) {519 GuardAction([this, old = move(enclosing_control_structures)](){520 enclosing_control_structures =move(old);521 });522 enclosing_control_structures = vector<Entry>();522 void MultiLevelExitCore::previsit( const ast::FinallyStmt * ) { 523 GuardAction([this, old = std::move(enclosing_control_structures)](){ 524 enclosing_control_structures = std::move(old); 525 }); 526 enclosing_control_structures = std::vector<Entry>(); 523 527 GuardValue( inFinally ) = true; 524 528 } 525 529 526 const Stmt * MultiLevelExitCore::mutateLoop(527 constStmt * body, Entry & entry ) {530 const ast::Stmt * MultiLevelExitCore::mutateLoop( 531 const ast::Stmt * body, Entry & entry ) { 528 532 if ( entry.isBreakUsed() ) { 529 533 break_label = entry.useBreakExit(); … … 531 535 532 536 if ( entry.isContUsed() ) { 533 CompoundStmt * new_body = newCompoundStmt( body->location );537 ast::CompoundStmt * new_body = new ast::CompoundStmt( body->location ); 534 538 new_body->kids.push_back( body ); 535 539 new_body->kids.push_back( … … 545 549 // Remember is loop before going onto mutate the body. 546 550 // The labels will be folded in if they are used. 547 Label breakLabel =newLabel( "loopBreak", loopStmt );548 Label contLabel =newLabel( "loopContinue", loopStmt );551 ast::Label breakLabel = LabelGenerator::newLabel( "loopBreak", loopStmt ); 552 ast::Label contLabel = LabelGenerator::newLabel( "loopContinue", loopStmt ); 549 553 enclosing_control_structures.emplace_back( loopStmt, breakLabel, contLabel ); 550 554 GuardAction( [this](){ enclosing_control_structures.pop_back(); } ); … … 557 561 assert( entry.stmt == loopStmt ); 558 562 559 // Now check if the labels are used and add them if so.560 return mutate_field(563 // Now we check if the labels are used and add them if so. 564 return ast::mutate_field( 561 565 loopStmt, &LoopNode::body, mutateLoop( loopStmt->body, entry ) ); 562 566 } 563 567 564 list<ptr<Stmt>> MultiLevelExitCore::fixBlock(565 const list<ptr<Stmt>> & kids, bool is_case_clause ) {566 // Unfortunately cannot use automatic error collection.568 std::list<ast::ptr<ast::Stmt>> MultiLevelExitCore::fixBlock( 569 const std::list<ast::ptr<ast::Stmt>> & kids, bool is_case_clause ) { 570 // Unfortunately we can't use the automatic error collection. 567 571 SemanticErrorException errors; 568 572 569 list<ptr<Stmt>> ret;573 std::list<ast::ptr<ast::Stmt>> ret; 570 574 571 575 // Manually visit each child. 572 for ( const ptr<Stmt> & kid : kids ) {576 for ( const ast::ptr<ast::Stmt> & kid : kids ) { 573 577 if ( is_case_clause ) { 574 578 // Once a label is seen, it's no longer a valid for fallthrough. 575 for ( const Label & l : kid->labels ) {579 for ( const ast::Label & l : kid->labels ) { 576 580 fallthrough_labels.erase( l ); 577 581 } … … 587 591 ret.push_back( 588 592 labelledNullStmt( ret.back()->location, break_label ) ); 589 break_label = Label( CodeLocation(), "" );593 break_label = ast::Label( CodeLocation(), "" ); 590 594 } 591 595 } … … 597 601 } 598 602 599 const CompoundStmt * multiLevelExitUpdate( 600 const CompoundStmt * stmt, 601 const LabelToStmt & labelTable ) { 603 } // namespace 604 605 const ast::CompoundStmt * multiLevelExitUpdate( 606 const ast::CompoundStmt * stmt, 607 const LabelToStmt & labelTable ) { 602 608 // Must start in the body, so FunctionDecls can be a stopping point. 603 Pass<MultiLevelExitCore> visitor( labelTable );604 const CompoundStmt * ret = stmt->accept( visitor );609 ast::Pass<MultiLevelExitCore> visitor( labelTable ); 610 const ast::CompoundStmt * ret = stmt->accept( visitor ); 605 611 return ret; 606 612 } 613 607 614 } // namespace ControlStruct 608 615
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