source: src/InitTweak/InitTweak.cc@ aac99da

ADT aaron-thesis arm-eh ast-experimental cleanup-dtors enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr persistent-indexer pthread-emulation qualifiedEnum
Last change on this file since aac99da was f072892, checked in by Rob Schluntz <rschlunt@…>, 7 years ago

Minor cleanup
  • Property mode set to 100644
File size: 24.3 KB
Line 
1#include <algorithm> // for find, all_of
2#include <cassert> // for assertf, assert, strict_dynamic_cast
3#include <iostream> // for ostream, cerr, endl
4#include <iterator> // for back_insert_iterator, back_inserter
5#include <memory> // for __shared_ptr
6
7#include "Common/PassVisitor.h"
8#include "Common/SemanticError.h" // for SemanticError
9#include "Common/UniqueName.h" // for UniqueName
10#include "Common/utility.h" // for toString, deleteAll, maybeClone
11#include "GenPoly/GenPoly.h" // for getFunctionType
12#include "InitTweak.h"
13#include "Parser/LinkageSpec.h" // for Spec, isBuiltin, Intrinsic
14#include "ResolvExpr/typeops.h" // for typesCompatibleIgnoreQualifiers
15#include "SymTab/Autogen.h"
16#include "SymTab/Indexer.h" // for Indexer
17#include "SynTree/Attribute.h" // for Attribute
18#include "SynTree/Constant.h" // for Constant
19#include "SynTree/Declaration.h" // for ObjectDecl, DeclarationWithType
20#include "SynTree/Expression.h" // for Expression, UntypedExpr, Applicati...
21#include "SynTree/Initializer.h" // for Initializer, ListInit, Designation
22#include "SynTree/Label.h" // for Label
23#include "SynTree/Statement.h" // for CompoundStmt, ExprStmt, BranchStmt
24#include "SynTree/Type.h" // for FunctionType, ArrayType, PointerType
25#include "SynTree/Visitor.h" // for Visitor, maybeAccept
26#include "Tuples/Tuples.h" // for Tuples::isTtype
27
28class UntypedValofExpr;
29
30namespace InitTweak {
31 namespace {
32 struct HasDesignations : public WithShortCircuiting {
33 bool hasDesignations = false;
34
35 void previsit( BaseSyntaxNode * ) {
36 // short circuit if we already know there are designations
37 if ( hasDesignations ) visit_children = false;
38 }
39
40 void previsit( Designation * des ) {
41 // short circuit if we already know there are designations
42 if ( hasDesignations ) visit_children = false;
43 else if ( ! des->get_designators().empty() ) {
44 hasDesignations = true;
45 visit_children = false;
46 }
47 }
48 };
49
50 struct InitDepthChecker : public WithGuards {
51 bool depthOkay = true;
52 Type * type;
53 int curDepth = 0, maxDepth = 0;
54 InitDepthChecker( Type * type ) : type( type ) {
55 Type * t = type;
56 while ( ArrayType * at = dynamic_cast< ArrayType * >( t ) ) {
57 maxDepth++;
58 t = at->get_base();
59 }
60 maxDepth++;
61 }
62 void previsit( ListInit * ) {
63 curDepth++;
64 GuardAction( [this]() { curDepth--; } );
65 if ( curDepth > maxDepth ) depthOkay = false;
66 }
67 };
68
69 struct InitFlattener : public WithShortCircuiting {
70 void previsit( SingleInit * singleInit ) {
71 visit_children = false;
72 argList.push_back( singleInit->value->clone() );
73 }
74 std::list< Expression * > argList;
75 };
76
77 }
78
79 std::list< Expression * > makeInitList( Initializer * init ) {
80 PassVisitor<InitFlattener> flattener;
81 maybeAccept( init, flattener );
82 return flattener.pass.argList;
83 }
84
85 bool isDesignated( Initializer * init ) {
86 PassVisitor<HasDesignations> finder;
87 maybeAccept( init, finder );
88 return finder.pass.hasDesignations;
89 }
90
91 bool checkInitDepth( ObjectDecl * objDecl ) {
92 PassVisitor<InitDepthChecker> checker( objDecl->type );
93 maybeAccept( objDecl->init, checker );
94 return checker.pass.depthOkay;
95 }
96
97 class InitExpander::ExpanderImpl {
98 public:
99 virtual ~ExpanderImpl() = default;
100 virtual std::list< Expression * > next( std::list< Expression * > & indices ) = 0;
101 virtual Statement * buildListInit( UntypedExpr * callExpr, std::list< Expression * > & indices ) = 0;
102 };
103
104 class InitImpl : public InitExpander::ExpanderImpl {
105 public:
106 InitImpl( Initializer * init ) : init( init ) {}
107 virtual ~InitImpl() = default;
108
109 virtual std::list< Expression * > next( __attribute((unused)) std::list< Expression * > & indices ) {
110 // this is wrong, but just a placeholder for now
111 // if ( ! flattened ) flatten( indices );
112 // return ! inits.empty() ? makeInitList( inits.front() ) : std::list< Expression * >();
113 return makeInitList( init );
114 }
115
116 virtual Statement * buildListInit( UntypedExpr * callExpr, std::list< Expression * > & indices );
117 private:
118 Initializer * init;
119 };
120
121 class ExprImpl : public InitExpander::ExpanderImpl {
122 public:
123 ExprImpl( Expression * expr ) : arg( expr ) {}
124 virtual ~ExprImpl() { delete arg; }
125
126 virtual std::list< Expression * > next( std::list< Expression * > & indices ) {
127 std::list< Expression * > ret;
128 Expression * expr = maybeClone( arg );
129 if ( expr ) {
130 for ( std::list< Expression * >::reverse_iterator it = indices.rbegin(); it != indices.rend(); ++it ) {
131 // go through indices and layer on subscript exprs ?[?]
132 ++it;
133 UntypedExpr * subscriptExpr = new UntypedExpr( new NameExpr( "?[?]") );
134 subscriptExpr->get_args().push_back( expr );
135 subscriptExpr->get_args().push_back( (*it)->clone() );
136 expr = subscriptExpr;
137 }
138 ret.push_back( expr );
139 }
140 return ret;
141 }
142
143 virtual Statement * buildListInit( UntypedExpr * callExpr, std::list< Expression * > & indices );
144 private:
145 Expression * arg;
146 };
147
148 InitExpander::InitExpander( Initializer * init ) : expander( new InitImpl( init ) ) {}
149
150 InitExpander::InitExpander( Expression * expr ) : expander( new ExprImpl( expr ) ) {}
151
152 std::list< Expression * > InitExpander::operator*() {
153 return cur;
154 }
155
156 InitExpander & InitExpander::operator++() {
157 cur = expander->next( indices );
158 return *this;
159 }
160
161 // use array indices list to build switch statement
162 void InitExpander::addArrayIndex( Expression * index, Expression * dimension ) {
163 indices.push_back( index );
164 indices.push_back( dimension );
165 }
166
167 void InitExpander::clearArrayIndices() {
168 deleteAll( indices );
169 indices.clear();
170 }
171
172 bool InitExpander::addReference() {
173 bool added = false;
174 for ( Expression *& expr : cur ) {
175 expr = new AddressExpr( expr );
176 added = true;
177 }
178 return added;
179 }
180
181 namespace {
182 /// given index i, dimension d, initializer init, and callExpr f, generates
183 /// if (i < d) f(..., init)
184 /// ++i;
185 /// so that only elements within the range of the array are constructed
186 template< typename OutIterator >
187 void buildCallExpr( UntypedExpr * callExpr, Expression * index, Expression * dimension, Initializer * init, OutIterator out ) {
188 UntypedExpr * cond = new UntypedExpr( new NameExpr( "?<?") );
189 cond->get_args().push_back( index->clone() );
190 cond->get_args().push_back( dimension->clone() );
191
192 std::list< Expression * > args = makeInitList( init );
193 callExpr->get_args().splice( callExpr->get_args().end(), args );
194
195 *out++ = new IfStmt( cond, new ExprStmt( callExpr ), nullptr );
196
197 UntypedExpr * increment = new UntypedExpr( new NameExpr( "++?" ) );
198 increment->get_args().push_back( index->clone() );
199 *out++ = new ExprStmt( increment );
200 }
201
202 template< typename OutIterator >
203 void build( UntypedExpr * callExpr, InitExpander::IndexList::iterator idx, InitExpander::IndexList::iterator idxEnd, Initializer * init, OutIterator out ) {
204 if ( idx == idxEnd ) return;
205 Expression * index = *idx++;
206 assert( idx != idxEnd );
207 Expression * dimension = *idx++;
208
209 // xxx - may want to eventually issue a warning here if we can detect
210 // that the number of elements exceeds to dimension of the array
211 if ( idx == idxEnd ) {
212 if ( ListInit * listInit = dynamic_cast< ListInit * >( init ) ) {
213 for ( Initializer * init : *listInit ) {
214 buildCallExpr( callExpr->clone(), index, dimension, init, out );
215 }
216 } else {
217 buildCallExpr( callExpr->clone(), index, dimension, init, out );
218 }
219 } else {
220 std::list< Statement * > branches;
221
222 unsigned long cond = 0;
223 ListInit * listInit = dynamic_cast< ListInit * >( init );
224 if ( ! listInit ) {
225 // xxx - this shouldn't be an error, but need a way to
226 // terminate without creating output, so should catch this error
227 SemanticError( init->location, "unbalanced list initializers" );
228 }
229
230 static UniqueName targetLabel( "L__autogen__" );
231 Label switchLabel( targetLabel.newName(), 0, std::list< Attribute * >{ new Attribute("unused") } );
232 for ( Initializer * init : *listInit ) {
233 Expression * condition;
234 // check for designations
235 // if ( init-> ) {
236 condition = new ConstantExpr( Constant::from_ulong( cond ) );
237 ++cond;
238 // } else {
239 // condition = // ... take designation
240 // cond = // ... take designation+1
241 // }
242 std::list< Statement * > stmts;
243 build( callExpr, idx, idxEnd, init, back_inserter( stmts ) );
244 stmts.push_back( new BranchStmt( switchLabel, BranchStmt::Break ) );
245 CaseStmt * caseStmt = new CaseStmt( condition, stmts );
246 branches.push_back( caseStmt );
247 }
248 *out++ = new SwitchStmt( index->clone(), branches );
249 *out++ = new NullStmt( { switchLabel } );
250 }
251 }
252 }
253
254 // if array came with an initializer list: initialize each element
255 // may have more initializers than elements in the array - need to check at each index that
256 // we haven't exceeded size.
257 // may have fewer initializers than elements in the array - need to default construct
258 // remaining elements.
259 // To accomplish this, generate switch statement, consuming all of expander's elements
260 Statement * InitImpl::buildListInit( UntypedExpr * dst, std::list< Expression * > & indices ) {
261 if ( ! init ) return nullptr;
262 CompoundStmt * block = new CompoundStmt();
263 build( dst, indices.begin(), indices.end(), init, back_inserter( block->get_kids() ) );
264 if ( block->get_kids().empty() ) {
265 delete block;
266 return nullptr;
267 } else {
268 init = nullptr; // init was consumed in creating the list init
269 return block;
270 }
271 }
272
273 Statement * ExprImpl::buildListInit( UntypedExpr *, std::list< Expression * > & ) {
274 return nullptr;
275 }
276
277 Statement * InitExpander::buildListInit( UntypedExpr * dst ) {
278 return expander->buildListInit( dst, indices );
279 }
280
281 Type * getTypeofThis( FunctionType * ftype ) {
282 assertf( ftype, "getTypeofThis: nullptr ftype" );
283 ObjectDecl * thisParam = getParamThis( ftype );
284 ReferenceType * refType = strict_dynamic_cast< ReferenceType * >( thisParam->type );
285 return refType->base;
286 }
287
288 ObjectDecl * getParamThis( FunctionType * ftype ) {
289 assertf( ftype, "getParamThis: nullptr ftype" );
290 auto & params = ftype->parameters;
291 assertf( ! params.empty(), "getParamThis: ftype with 0 parameters: %s", toString( ftype ).c_str() );
292 return strict_dynamic_cast< ObjectDecl * >( params.front() );
293 }
294
295 bool tryConstruct( DeclarationWithType * dwt ) {
296 ObjectDecl * objDecl = dynamic_cast< ObjectDecl * >( dwt );
297 if ( ! objDecl ) return false;
298 return (objDecl->get_init() == nullptr ||
299 ( objDecl->get_init() != nullptr && objDecl->get_init()->get_maybeConstructed() ))
300 && ! objDecl->get_storageClasses().is_extern
301 && isConstructable( objDecl->type );
302 }
303
304 bool isConstructable( Type * type ) {
305 return ! dynamic_cast< VarArgsType * >( type ) && ! dynamic_cast< ReferenceType * >( type ) && ! dynamic_cast< FunctionType * >( type ) && ! Tuples::isTtype( type );
306 }
307
308 struct CallFinder {
309 CallFinder( const std::list< std::string > & names ) : names( names ) {}
310
311 void postvisit( ApplicationExpr * appExpr ) {
312 handleCallExpr( appExpr );
313 }
314
315 void postvisit( UntypedExpr * untypedExpr ) {
316 handleCallExpr( untypedExpr );
317 }
318
319 std::list< Expression * > * matches;
320 private:
321 const std::list< std::string > names;
322
323 template< typename CallExpr >
324 void handleCallExpr( CallExpr * expr ) {
325 std::string fname = getFunctionName( expr );
326 if ( std::find( names.begin(), names.end(), fname ) != names.end() ) {
327 matches->push_back( expr );
328 }
329 }
330 };
331
332 void collectCtorDtorCalls( Statement * stmt, std::list< Expression * > & matches ) {
333 static PassVisitor<CallFinder> finder( std::list< std::string >{ "?{}", "^?{}" } );
334 finder.pass.matches = &matches;
335 maybeAccept( stmt, finder );
336 }
337
338 Expression * getCtorDtorCall( Statement * stmt ) {
339 std::list< Expression * > matches;
340 collectCtorDtorCalls( stmt, matches );
341 assert( matches.size() <= 1 );
342 return matches.size() == 1 ? matches.front() : nullptr;
343 }
344
345 namespace {
346 DeclarationWithType * getCalledFunction( Expression * expr );
347
348 template<typename CallExpr>
349 DeclarationWithType * handleDerefCalledFunction( CallExpr * expr ) {
350 // (*f)(x) => should get "f"
351 std::string name = getFunctionName( expr );
352 assertf( name == "*?", "Unexpected untyped expression: %s", name.c_str() );
353 assertf( ! expr->get_args().empty(), "Cannot get called function from dereference with no arguments" );
354 return getCalledFunction( expr->get_args().front() );
355 }
356
357 DeclarationWithType * getCalledFunction( Expression * expr ) {
358 assert( expr );
359 if ( VariableExpr * varExpr = dynamic_cast< VariableExpr * >( expr ) ) {
360 return varExpr->var;
361 } else if ( MemberExpr * memberExpr = dynamic_cast< MemberExpr * >( expr ) ) {
362 return memberExpr->member;
363 } else if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( expr ) ) {
364 return getCalledFunction( castExpr->arg );
365 } else if ( UntypedExpr * untypedExpr = dynamic_cast< UntypedExpr * >( expr ) ) {
366 return handleDerefCalledFunction( untypedExpr );
367 } else if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * > ( expr ) ) {
368 return handleDerefCalledFunction( appExpr );
369 } else if ( AddressExpr * addrExpr = dynamic_cast< AddressExpr * >( expr ) ) {
370 return getCalledFunction( addrExpr->arg );
371 } else if ( CommaExpr * commaExpr = dynamic_cast< CommaExpr * >( expr ) ) {
372 return getCalledFunction( commaExpr->arg2 );
373 }
374 return nullptr;
375 }
376 }
377
378 DeclarationWithType * getFunction( Expression * expr ) {
379 if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( expr ) ) {
380 return getCalledFunction( appExpr->get_function() );
381 } else if ( UntypedExpr * untyped = dynamic_cast< UntypedExpr * > ( expr ) ) {
382 return getCalledFunction( untyped->get_function() );
383 }
384 assertf( false, "getFunction received unknown expression: %s", toString( expr ).c_str() );
385 }
386
387 ApplicationExpr * isIntrinsicCallExpr( Expression * expr ) {
388 ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( expr );
389 if ( ! appExpr ) return nullptr;
390 DeclarationWithType * function = getCalledFunction( appExpr->get_function() );
391 assertf( function, "getCalledFunction returned nullptr: %s", toString( appExpr->get_function() ).c_str() );
392 // check for Intrinsic only - don't want to remove all overridable ctor/dtors because autogenerated ctor/dtor
393 // will call all member dtors, and some members may have a user defined dtor.
394 return function->get_linkage() == LinkageSpec::Intrinsic ? appExpr : nullptr;
395 }
396
397 namespace {
398 template <typename Predicate>
399 bool allofCtorDtor( Statement * stmt, const Predicate & pred ) {
400 std::list< Expression * > callExprs;
401 collectCtorDtorCalls( stmt, callExprs );
402 // if ( callExprs.empty() ) return false; // xxx - do I still need this check?
403 return std::all_of( callExprs.begin(), callExprs.end(), pred);
404 }
405 }
406
407 bool isIntrinsicSingleArgCallStmt( Statement * stmt ) {
408 return allofCtorDtor( stmt, []( Expression * callExpr ){
409 if ( ApplicationExpr * appExpr = isIntrinsicCallExpr( callExpr ) ) {
410 FunctionType *funcType = GenPoly::getFunctionType( appExpr->function->result );
411 assert( funcType );
412 return funcType->get_parameters().size() == 1;
413 }
414 return false;
415 });
416 }
417
418 bool isIntrinsicCallStmt( Statement * stmt ) {
419 return allofCtorDtor( stmt, []( Expression * callExpr ) {
420 return isIntrinsicCallExpr( callExpr );
421 });
422 }
423
424 namespace {
425 template<typename CallExpr>
426 Expression *& callArg( CallExpr * callExpr, unsigned int pos ) {
427 if ( pos >= callExpr->get_args().size() ) assertf( false, "getCallArg for argument that doesn't exist: (%u); %s.", pos, toString( callExpr ).c_str() );
428 for ( Expression *& arg : callExpr->get_args() ) {
429 if ( pos == 0 ) return arg;
430 pos--;
431 }
432 assert( false );
433 }
434 }
435
436 Expression *& getCallArg( Expression * callExpr, unsigned int pos ) {
437 if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( callExpr ) ) {
438 return callArg( appExpr, pos );
439 } else if ( UntypedExpr * untypedExpr = dynamic_cast< UntypedExpr * >( callExpr ) ) {
440 return callArg( untypedExpr, pos );
441 } else if ( TupleAssignExpr * tupleExpr = dynamic_cast< TupleAssignExpr * > ( callExpr ) ) {
442 std::list< Statement * > & stmts = tupleExpr->get_stmtExpr()->get_statements()->get_kids();
443 assertf( ! stmts.empty(), "TupleAssignExpr somehow has no statements." );
444 ExprStmt * stmt = strict_dynamic_cast< ExprStmt * >( stmts.back() );
445 TupleExpr * tuple = strict_dynamic_cast< TupleExpr * >( stmt->get_expr() );
446 assertf( ! tuple->get_exprs().empty(), "TupleAssignExpr somehow has empty tuple expr." );
447 return getCallArg( tuple->get_exprs().front(), pos );
448 } else if ( ImplicitCopyCtorExpr * copyCtor = dynamic_cast< ImplicitCopyCtorExpr * >( callExpr ) ) {
449 return getCallArg( copyCtor->callExpr, pos );
450 } else {
451 assertf( false, "Unexpected expression type passed to getCallArg: %s", toString( callExpr ).c_str() );
452 }
453 }
454
455 namespace {
456 std::string funcName( Expression * func );
457
458 template<typename CallExpr>
459 std::string handleDerefName( CallExpr * expr ) {
460 // (*f)(x) => should get name "f"
461 std::string name = getFunctionName( expr );
462 assertf( name == "*?", "Unexpected untyped expression: %s", name.c_str() );
463 assertf( ! expr->get_args().empty(), "Cannot get function name from dereference with no arguments" );
464 return funcName( expr->get_args().front() );
465 }
466
467 std::string funcName( Expression * func ) {
468 if ( NameExpr * nameExpr = dynamic_cast< NameExpr * >( func ) ) {
469 return nameExpr->get_name();
470 } else if ( VariableExpr * varExpr = dynamic_cast< VariableExpr * >( func ) ) {
471 return varExpr->get_var()->get_name();
472 } else if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( func ) ) {
473 return funcName( castExpr->get_arg() );
474 } else if ( MemberExpr * memberExpr = dynamic_cast< MemberExpr * >( func ) ) {
475 return memberExpr->get_member()->get_name();
476 } else if ( UntypedMemberExpr * memberExpr = dynamic_cast< UntypedMemberExpr * > ( func ) ) {
477 return funcName( memberExpr->get_member() );
478 } else if ( UntypedExpr * untypedExpr = dynamic_cast< UntypedExpr * >( func ) ) {
479 return handleDerefName( untypedExpr );
480 } else if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( func ) ) {
481 return handleDerefName( appExpr );
482 } else if ( ConstructorExpr * ctorExpr = dynamic_cast< ConstructorExpr * >( func ) ) {
483 return funcName( getCallArg( ctorExpr->get_callExpr(), 0 ) );
484 } else {
485 assertf( false, "Unexpected expression type being called as a function in call expression: %s", toString( func ).c_str() );
486 }
487 }
488 }
489
490 std::string getFunctionName( Expression * expr ) {
491 // there's some unforunate overlap here with getCalledFunction. Ideally this would be able to use getCalledFunction and
492 // return the name of the DeclarationWithType, but this needs to work for NameExpr and UntypedMemberExpr, where getCalledFunction
493 // can't possibly do anything reasonable.
494 if ( ApplicationExpr * appExpr = dynamic_cast< ApplicationExpr * >( expr ) ) {
495 return funcName( appExpr->get_function() );
496 } else if ( UntypedExpr * untypedExpr = dynamic_cast< UntypedExpr * > ( expr ) ) {
497 return funcName( untypedExpr->get_function() );
498 } else {
499 std::cerr << expr << std::endl;
500 assertf( false, "Unexpected expression type passed to getFunctionName" );
501 }
502 }
503
504 Type * getPointerBase( Type * type ) {
505 if ( PointerType * ptrType = dynamic_cast< PointerType * >( type ) ) {
506 return ptrType->get_base();
507 } else if ( ArrayType * arrayType = dynamic_cast< ArrayType * >( type ) ) {
508 return arrayType->get_base();
509 } else if ( ReferenceType * refType = dynamic_cast< ReferenceType * >( type ) ) {
510 return refType->get_base();
511 } else {
512 return nullptr;
513 }
514 }
515
516 Type * isPointerType( Type * type ) {
517 if ( getPointerBase( type ) ) return type;
518 else return nullptr;
519 }
520
521 ApplicationExpr * createBitwiseAssignment( Expression * dst, Expression * src ) {
522 static FunctionDecl * assign = nullptr;
523 if ( ! assign ) {
524 // temporary? Generate a fake assignment operator to represent bitwise assignments.
525 // This operator could easily exist as a real function, but it's tricky because nothing should resolve to this function.
526 TypeDecl * td = new TypeDecl( "T", noStorageClasses, nullptr, TypeDecl::Dtype, true );
527 assign = new FunctionDecl( "?=?", noStorageClasses, LinkageSpec::Intrinsic, SymTab::genAssignType( new TypeInstType( noQualifiers, td->name, td ) ), nullptr );
528 }
529 if ( dynamic_cast< ReferenceType * >( dst->result ) ) {
530 for (int depth = dst->result->referenceDepth(); depth > 0; depth--) {
531 dst = new AddressExpr( dst );
532 }
533 } else {
534 dst = new CastExpr( dst, new ReferenceType( noQualifiers, dst->result->clone() ) );
535 }
536 if ( dynamic_cast< ReferenceType * >( src->result ) ) {
537 for (int depth = src->result->referenceDepth(); depth > 0; depth--) {
538 src = new AddressExpr( src );
539 }
540 // src = new CastExpr( src, new ReferenceType( noQualifiers, src->result->stripReferences()->clone() ) );
541 }
542 return new ApplicationExpr( VariableExpr::functionPointer( assign ), { dst, src } );
543 }
544
545 struct ConstExprChecker : public WithShortCircuiting {
546 // most expressions are not const expr
547 void previsit( Expression * ) { isConstExpr = false; visit_children = false; }
548
549 void previsit( AddressExpr *addressExpr ) {
550 visit_children = false;
551
552 // address of a variable or member expression is constexpr
553 Expression * arg = addressExpr->get_arg();
554 if ( ! dynamic_cast< NameExpr * >( arg) && ! dynamic_cast< VariableExpr * >( arg ) && ! dynamic_cast< MemberExpr * >( arg ) && ! dynamic_cast< UntypedMemberExpr * >( arg ) ) isConstExpr = false;
555 }
556
557 // these expressions may be const expr, depending on their children
558 void previsit( SizeofExpr * ) {}
559 void previsit( AlignofExpr * ) {}
560 void previsit( UntypedOffsetofExpr * ) {}
561 void previsit( OffsetofExpr * ) {}
562 void previsit( OffsetPackExpr * ) {}
563 void previsit( AttrExpr * ) {}
564 void previsit( CommaExpr * ) {}
565 void previsit( LogicalExpr * ) {}
566 void previsit( ConditionalExpr * ) {}
567 void previsit( CastExpr * ) {}
568 void previsit( ConstantExpr * ) {}
569
570 void previsit( VariableExpr * varExpr ) {
571 visit_children = false;
572
573 if ( EnumInstType * inst = dynamic_cast< EnumInstType * >( varExpr->result ) ) {
574 long long int value;
575 if ( inst->baseEnum->valueOf( varExpr->var, value ) ) {
576 // enumerators are const expr
577 return;
578 }
579 }
580 isConstExpr = false;
581 }
582
583 bool isConstExpr = true;
584 };
585
586 bool isConstExpr( Expression * expr ) {
587 if ( expr ) {
588 PassVisitor<ConstExprChecker> checker;
589 expr->accept( checker );
590 return checker.pass.isConstExpr;
591 }
592 return true;
593 }
594
595 bool isConstExpr( Initializer * init ) {
596 if ( init ) {
597 PassVisitor<ConstExprChecker> checker;
598 init->accept( checker );
599 return checker.pass.isConstExpr;
600 } // if
601 // for all intents and purposes, no initializer means const expr
602 return true;
603 }
604
605 bool isConstructor( const std::string & str ) { return str == "?{}"; }
606 bool isDestructor( const std::string & str ) { return str == "^?{}"; }
607 bool isAssignment( const std::string & str ) { return str == "?=?"; }
608 bool isCtorDtor( const std::string & str ) { return isConstructor( str ) || isDestructor( str ); }
609 bool isCtorDtorAssign( const std::string & str ) { return isCtorDtor( str ) || isAssignment( str ); }
610
611 FunctionDecl * isCopyFunction( Declaration * decl, const std::string & fname ) {
612 FunctionDecl * function = dynamic_cast< FunctionDecl * >( decl );
613 if ( ! function ) return nullptr;
614 if ( function->name != fname ) return nullptr;
615 FunctionType * ftype = function->type;
616 if ( ftype->parameters.size() != 2 ) return nullptr;
617
618 Type * t1 = getPointerBase( ftype->get_parameters().front()->get_type() );
619 Type * t2 = ftype->parameters.back()->get_type();
620 assert( t1 );
621
622 if ( ResolvExpr::typesCompatibleIgnoreQualifiers( t1, t2, SymTab::Indexer() ) ) {
623 return function;
624 } else {
625 return nullptr;
626 }
627 }
628
629 FunctionDecl * isAssignment( Declaration * decl ) {
630 return isCopyFunction( decl, "?=?" );
631 }
632 FunctionDecl * isDestructor( Declaration * decl ) {
633 if ( isDestructor( decl->get_name() ) ) {
634 return dynamic_cast< FunctionDecl * >( decl );
635 }
636 return nullptr;
637 }
638 FunctionDecl * isDefaultConstructor( Declaration * decl ) {
639 if ( isConstructor( decl->name ) ) {
640 if ( FunctionDecl * func = dynamic_cast< FunctionDecl * >( decl ) ) {
641 if ( func->type->parameters.size() == 1 ) {
642 return func;
643 }
644 }
645 }
646 return nullptr;
647 }
648 FunctionDecl * isCopyConstructor( Declaration * decl ) {
649 return isCopyFunction( decl, "?{}" );
650 }
651}
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