source: src/ResolvExpr/Resolver.cc@ 57e0289

ADT arm-eh ast-experimental enum forall-pointer-decay jacob/cs343-translation new-ast-unique-expr pthread-emulation qualifiedEnum
Last change on this file since 57e0289 was 57e0289, checked in by Thierry Delisle <tdelisle@…>, 5 years ago

Added stats option to print stats per expression in new-ast resolution

  • Property mode set to 100644
File size: 68.1 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// Resolver.cc --
8//
9// Author : Aaron B. Moss
10// Created On : Sun May 17 12:17:01 2015
11// Last Modified By : Andrew Beach
12// Last Modified On : Fri Mar 27 11:58:00 2020
13// Update Count : 242
14//
15
16#include <cassert> // for strict_dynamic_cast, assert
17#include <memory> // for allocator, allocator_traits<...
18#include <tuple> // for get
19#include <vector> // for vector
20
21#include "Alternative.h" // for Alternative, AltList
22#include "AlternativeFinder.h" // for AlternativeFinder, resolveIn...
23#include "Candidate.hpp"
24#include "CandidateFinder.hpp"
25#include "CurrentObject.h" // for CurrentObject
26#include "RenameVars.h" // for RenameVars, global_renamer
27#include "Resolver.h"
28#include "ResolvMode.h" // for ResolvMode
29#include "typeops.h" // for extractResultType
30#include "Unify.h" // for unify
31#include "AST/Chain.hpp"
32#include "AST/Decl.hpp"
33#include "AST/Init.hpp"
34#include "AST/Pass.hpp"
35#include "AST/Print.hpp"
36#include "AST/SymbolTable.hpp"
37#include "AST/Type.hpp"
38#include "Common/PassVisitor.h" // for PassVisitor
39#include "Common/SemanticError.h" // for SemanticError
40#include "Common/Stats/ResolveTime.h" // for ResolveTime::start(), ResolveTime::stop()
41#include "Common/utility.h" // for ValueGuard, group_iterate
42#include "InitTweak/GenInit.h"
43#include "InitTweak/InitTweak.h" // for isIntrinsicSingleArgCallStmt
44#include "ResolvExpr/TypeEnvironment.h" // for TypeEnvironment
45#include "SymTab/Autogen.h" // for SizeType
46#include "SymTab/Indexer.h" // for Indexer
47#include "SynTree/Declaration.h" // for ObjectDecl, TypeDecl, Declar...
48#include "SynTree/Expression.h" // for Expression, CastExpr, InitExpr
49#include "SynTree/Initializer.h" // for ConstructorInit, SingleInit
50#include "SynTree/Statement.h" // for ForStmt, Statement, BranchStmt
51#include "SynTree/Type.h" // for Type, BasicType, PointerType
52#include "SynTree/TypeSubstitution.h" // for TypeSubstitution
53#include "SynTree/Visitor.h" // for acceptAll, maybeAccept
54#include "Tuples/Tuples.h"
55#include "Validate/FindSpecialDecls.h" // for SizeType
56
57using namespace std;
58
59namespace ResolvExpr {
60 struct Resolver_old final : public WithIndexer, public WithGuards, public WithVisitorRef<Resolver_old>, public WithShortCircuiting, public WithStmtsToAdd {
61 Resolver_old() {}
62 Resolver_old( const SymTab::Indexer & other ) {
63 indexer = other;
64 }
65
66 void previsit( FunctionDecl * functionDecl );
67 void postvisit( FunctionDecl * functionDecl );
68 void previsit( ObjectDecl * objectDecll );
69 void previsit( EnumDecl * enumDecl );
70 void previsit( StaticAssertDecl * assertDecl );
71
72 void previsit( ArrayType * at );
73 void previsit( PointerType * at );
74
75 void previsit( ExprStmt * exprStmt );
76 void previsit( AsmExpr * asmExpr );
77 void previsit( AsmStmt * asmStmt );
78 void previsit( IfStmt * ifStmt );
79 void previsit( WhileStmt * whileStmt );
80 void previsit( ForStmt * forStmt );
81 void previsit( SwitchStmt * switchStmt );
82 void previsit( CaseStmt * caseStmt );
83 void previsit( BranchStmt * branchStmt );
84 void previsit( ReturnStmt * returnStmt );
85 void previsit( ThrowStmt * throwStmt );
86 void previsit( CatchStmt * catchStmt );
87 void postvisit( CatchStmt * catchStmt );
88 void previsit( WaitForStmt * stmt );
89
90 void previsit( SingleInit * singleInit );
91 void previsit( ListInit * listInit );
92 void previsit( ConstructorInit * ctorInit );
93 private:
94 typedef std::list< Initializer * >::iterator InitIterator;
95
96 template< typename PtrType >
97 void handlePtrType( PtrType * type );
98
99 void fallbackInit( ConstructorInit * ctorInit );
100
101 Type * functionReturn = nullptr;
102 CurrentObject currentObject = nullptr;
103 bool inEnumDecl = false;
104 };
105
106 struct ResolveWithExprs : public WithIndexer, public WithGuards, public WithVisitorRef<ResolveWithExprs>, public WithShortCircuiting, public WithStmtsToAdd {
107 void previsit( FunctionDecl * );
108 void previsit( WithStmt * );
109
110 void resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts );
111 };
112
113 void resolve( std::list< Declaration * > translationUnit ) {
114 PassVisitor<Resolver_old> resolver;
115 acceptAll( translationUnit, resolver );
116 }
117
118 void resolveDecl( Declaration * decl, const SymTab::Indexer & indexer ) {
119 PassVisitor<Resolver_old> resolver( indexer );
120 maybeAccept( decl, resolver );
121 }
122
123 namespace {
124 struct DeleteFinder_old : public WithShortCircuiting {
125 DeletedExpr * delExpr = nullptr;
126 void previsit( DeletedExpr * expr ) {
127 if ( delExpr ) visit_children = false;
128 else delExpr = expr;
129 }
130
131 void previsit( Expression * ) {
132 if ( delExpr ) visit_children = false;
133 }
134 };
135 }
136
137 DeletedExpr * findDeletedExpr( Expression * expr ) {
138 PassVisitor<DeleteFinder_old> finder;
139 expr->accept( finder );
140 return finder.pass.delExpr;
141 }
142
143 namespace {
144 struct StripCasts_old {
145 Expression * postmutate( CastExpr * castExpr ) {
146 if ( castExpr->isGenerated && ResolvExpr::typesCompatible( castExpr->arg->result, castExpr->result, SymTab::Indexer() ) ) {
147 // generated cast is to the same type as its argument, so it's unnecessary -- remove it
148 Expression * expr = castExpr->arg;
149 castExpr->arg = nullptr;
150 std::swap( expr->env, castExpr->env );
151 return expr;
152 }
153 return castExpr;
154 }
155
156 static void strip( Expression *& expr ) {
157 PassVisitor<StripCasts_old> stripper;
158 expr = expr->acceptMutator( stripper );
159 }
160 };
161
162 void finishExpr( Expression *& expr, const TypeEnvironment & env, TypeSubstitution * oldenv = nullptr ) {
163 expr->env = oldenv ? oldenv->clone() : new TypeSubstitution;
164 env.makeSubstitution( *expr->env );
165 StripCasts_old::strip( expr ); // remove unnecessary casts that may be buried in an expression
166 }
167
168 void removeExtraneousCast( Expression *& expr, const SymTab::Indexer & indexer ) {
169 if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( expr ) ) {
170 if ( typesCompatible( castExpr->arg->result, castExpr->result, indexer ) ) {
171 // cast is to the same type as its argument, so it's unnecessary -- remove it
172 expr = castExpr->arg;
173 castExpr->arg = nullptr;
174 std::swap( expr->env, castExpr->env );
175 delete castExpr;
176 }
177 }
178 }
179 } // namespace
180
181 namespace {
182 void findUnfinishedKindExpression(Expression * untyped, Alternative & alt, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, ResolvMode mode = ResolvMode{} ) {
183 assertf( untyped, "expected a non-null expression." );
184
185 // xxx - this isn't thread-safe, but should work until we parallelize the resolver
186 static unsigned recursion_level = 0;
187
188 ++recursion_level;
189 TypeEnvironment env;
190 AlternativeFinder finder( indexer, env );
191 finder.find( untyped, recursion_level == 1 ? mode.atTopLevel() : mode );
192 --recursion_level;
193
194 #if 0
195 if ( finder.get_alternatives().size() != 1 ) {
196 std::cerr << "untyped expr is ";
197 untyped->print( std::cerr );
198 std::cerr << std::endl << "alternatives are:";
199 for ( const Alternative & alt : finder.get_alternatives() ) {
200 alt.print( std::cerr );
201 } // for
202 } // if
203 #endif
204
205 // produce filtered list of alternatives
206 AltList candidates;
207 for ( Alternative & alt : finder.get_alternatives() ) {
208 if ( pred( alt ) ) {
209 candidates.push_back( std::move( alt ) );
210 }
211 }
212
213 // produce invalid error if no candidates
214 if ( candidates.empty() ) {
215 SemanticError( untyped, toString( "No reasonable alternatives for ", kindStr, (kindStr != "" ? " " : ""), "expression: ") );
216 }
217
218 // search for cheapest candidate
219 AltList winners;
220 bool seen_undeleted = false;
221 for ( unsigned i = 0; i < candidates.size(); ++i ) {
222 int c = winners.empty() ? -1 : candidates[i].cost.compare( winners.front().cost );
223
224 if ( c > 0 ) continue; // skip more expensive than winner
225
226 if ( c < 0 ) {
227 // reset on new cheapest
228 seen_undeleted = ! findDeletedExpr( candidates[i].expr );
229 winners.clear();
230 } else /* if ( c == 0 ) */ {
231 if ( findDeletedExpr( candidates[i].expr ) ) {
232 // skip deleted expression if already seen one equivalent-cost not
233 if ( seen_undeleted ) continue;
234 } else if ( ! seen_undeleted ) {
235 // replace list of equivalent-cost deleted expressions with one non-deleted
236 winners.clear();
237 seen_undeleted = true;
238 }
239 }
240
241 winners.emplace_back( std::move( candidates[i] ) );
242 }
243
244 // promote alternative.cvtCost to .cost
245 // xxx - I don't know why this is done, but I'm keeping the behaviour from findMinCost
246 for ( Alternative& winner : winners ) {
247 winner.cost = winner.cvtCost;
248 }
249
250 // produce ambiguous errors, if applicable
251 if ( winners.size() != 1 ) {
252 std::ostringstream stream;
253 stream << "Cannot choose between " << winners.size() << " alternatives for " << kindStr << (kindStr != "" ? " " : "") << "expression\n";
254 untyped->print( stream );
255 stream << " Alternatives are:\n";
256 printAlts( winners, stream, 1 );
257 SemanticError( untyped->location, stream.str() );
258 }
259
260 // single selected choice
261 Alternative& choice = winners.front();
262
263 // fail on only expression deleted
264 if ( ! seen_undeleted ) {
265 SemanticError( untyped->location, choice.expr, "Unique best alternative includes deleted identifier in " );
266 }
267
268 // xxx - check for ambiguous expressions
269
270 // output selected choice
271 alt = std::move( choice );
272 }
273
274 /// resolve `untyped` to the expression whose alternative satisfies `pred` with the lowest cost; kindStr is used for providing better error messages
275 void findKindExpression(Expression *& untyped, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, ResolvMode mode = ResolvMode{}) {
276 if ( ! untyped ) return;
277 Alternative choice;
278 findUnfinishedKindExpression( untyped, choice, indexer, kindStr, pred, mode );
279 finishExpr( choice.expr, choice.env, untyped->env );
280 delete untyped;
281 untyped = choice.expr;
282 choice.expr = nullptr;
283 }
284
285 bool standardAlternativeFilter( const Alternative & ) {
286 // currently don't need to filter, under normal circumstances.
287 // in the future, this may be useful for removing deleted expressions
288 return true;
289 }
290 } // namespace
291
292 // used in resolveTypeof
293 Expression * resolveInVoidContext( Expression * expr, const SymTab::Indexer & indexer ) {
294 TypeEnvironment env;
295 return resolveInVoidContext( expr, indexer, env );
296 }
297
298 Expression * resolveInVoidContext( Expression * expr, const SymTab::Indexer & indexer, TypeEnvironment & env ) {
299 // it's a property of the language that a cast expression has either 1 or 0 interpretations; if it has 0
300 // interpretations, an exception has already been thrown.
301 assertf( expr, "expected a non-null expression." );
302
303 CastExpr * untyped = new CastExpr( expr ); // cast to void
304 untyped->location = expr->location;
305
306 // set up and resolve expression cast to void
307 Alternative choice;
308 findUnfinishedKindExpression( untyped, choice, indexer, "", standardAlternativeFilter, ResolvMode::withAdjustment() );
309 CastExpr * castExpr = strict_dynamic_cast< CastExpr * >( choice.expr );
310 assert( castExpr );
311 env = std::move( choice.env );
312
313 // clean up resolved expression
314 Expression * ret = castExpr->arg;
315 castExpr->arg = nullptr;
316
317 // unlink the arg so that it isn't deleted twice at the end of the program
318 untyped->arg = nullptr;
319 return ret;
320 }
321
322 void findVoidExpression( Expression *& untyped, const SymTab::Indexer & indexer ) {
323 resetTyVarRenaming();
324 TypeEnvironment env;
325 Expression * newExpr = resolveInVoidContext( untyped, indexer, env );
326 finishExpr( newExpr, env, untyped->env );
327 delete untyped;
328 untyped = newExpr;
329 }
330
331 void findSingleExpression( Expression *& untyped, const SymTab::Indexer & indexer ) {
332 findKindExpression( untyped, indexer, "", standardAlternativeFilter );
333 }
334
335 void findSingleExpression( Expression *& untyped, Type * type, const SymTab::Indexer & indexer ) {
336 assert( untyped && type );
337 // transfer location to generated cast for error purposes
338 CodeLocation location = untyped->location;
339 untyped = new CastExpr( untyped, type );
340 untyped->location = location;
341 findSingleExpression( untyped, indexer );
342 removeExtraneousCast( untyped, indexer );
343 }
344
345 namespace {
346 bool isIntegralType( const Alternative & alt ) {
347 Type * type = alt.expr->result;
348 if ( dynamic_cast< EnumInstType * >( type ) ) {
349 return true;
350 } else if ( BasicType * bt = dynamic_cast< BasicType * >( type ) ) {
351 return bt->isInteger();
352 } else if ( dynamic_cast< ZeroType* >( type ) != nullptr || dynamic_cast< OneType* >( type ) != nullptr ) {
353 return true;
354 } else {
355 return false;
356 } // if
357 }
358
359 void findIntegralExpression( Expression *& untyped, const SymTab::Indexer & indexer ) {
360 findKindExpression( untyped, indexer, "condition", isIntegralType );
361 }
362 }
363
364
365 bool isStructOrUnion( const Alternative & alt ) {
366 Type * t = alt.expr->result->stripReferences();
367 return dynamic_cast< StructInstType * >( t ) || dynamic_cast< UnionInstType * >( t );
368 }
369
370 void resolveWithExprs( std::list< Declaration * > & translationUnit ) {
371 PassVisitor<ResolveWithExprs> resolver;
372 acceptAll( translationUnit, resolver );
373 }
374
375 void ResolveWithExprs::resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts ) {
376 for ( Expression *& expr : withExprs ) {
377 // only struct- and union-typed expressions are viable candidates
378 findKindExpression( expr, indexer, "with statement", isStructOrUnion );
379
380 // if with expression might be impure, create a temporary so that it is evaluated once
381 if ( Tuples::maybeImpure( expr ) ) {
382 static UniqueName tmpNamer( "_with_tmp_" );
383 ObjectDecl * tmp = ObjectDecl::newObject( tmpNamer.newName(), expr->result->clone(), new SingleInit( expr ) );
384 expr = new VariableExpr( tmp );
385 newStmts.push_back( new DeclStmt( tmp ) );
386 if ( InitTweak::isConstructable( tmp->type ) ) {
387 // generate ctor/dtor and resolve them
388 tmp->init = InitTweak::genCtorInit( tmp );
389 tmp->accept( *visitor );
390 }
391 }
392 }
393 }
394
395 void ResolveWithExprs::previsit( WithStmt * withStmt ) {
396 resolveWithExprs( withStmt->exprs, stmtsToAddBefore );
397 }
398
399 void ResolveWithExprs::previsit( FunctionDecl * functionDecl ) {
400 {
401 // resolve with-exprs with parameters in scope and add any newly generated declarations to the
402 // front of the function body.
403 auto guard = makeFuncGuard( [this]() { indexer.enterScope(); }, [this](){ indexer.leaveScope(); } );
404 indexer.addFunctionType( functionDecl->type );
405 std::list< Statement * > newStmts;
406 resolveWithExprs( functionDecl->withExprs, newStmts );
407 if ( functionDecl->statements ) {
408 functionDecl->statements->kids.splice( functionDecl->statements->kids.begin(), newStmts );
409 } else {
410 assertf( functionDecl->withExprs.empty() && newStmts.empty(), "Function %s without a body has with-clause and/or generated with declarations.", functionDecl->name.c_str() );
411 }
412 }
413 }
414
415 void Resolver_old::previsit( ObjectDecl * objectDecl ) {
416 // To handle initialization of routine pointers, e.g., int (*fp)(int) = foo(), means that
417 // class-variable initContext is changed multiple time because the LHS is analysed twice.
418 // The second analysis changes initContext because of a function type can contain object
419 // declarations in the return and parameter types. So each value of initContext is
420 // retained, so the type on the first analysis is preserved and used for selecting the RHS.
421 GuardValue( currentObject );
422 currentObject = CurrentObject( objectDecl->get_type() );
423 if ( inEnumDecl && dynamic_cast< EnumInstType * >( objectDecl->get_type() ) ) {
424 // enumerator initializers should not use the enum type to initialize, since
425 // the enum type is still incomplete at this point. Use signed int instead.
426 currentObject = CurrentObject( new BasicType( Type::Qualifiers(), BasicType::SignedInt ) );
427 }
428 }
429
430 template< typename PtrType >
431 void Resolver_old::handlePtrType( PtrType * type ) {
432 if ( type->get_dimension() ) {
433 findSingleExpression( type->dimension, Validate::SizeType->clone(), indexer );
434 }
435 }
436
437 void Resolver_old::previsit( ArrayType * at ) {
438 handlePtrType( at );
439 }
440
441 void Resolver_old::previsit( PointerType * pt ) {
442 handlePtrType( pt );
443 }
444
445 void Resolver_old::previsit( FunctionDecl * functionDecl ) {
446#if 0
447 std::cerr << "resolver visiting functiondecl ";
448 functionDecl->print( std::cerr );
449 std::cerr << std::endl;
450#endif
451 GuardValue( functionReturn );
452 functionReturn = ResolvExpr::extractResultType( functionDecl->type );
453 }
454
455 void Resolver_old::postvisit( FunctionDecl * functionDecl ) {
456 // default value expressions have an environment which shouldn't be there and trips up
457 // later passes.
458 // xxx - it might be necessary to somehow keep the information from this environment, but I
459 // can't currently see how it's useful.
460 for ( Declaration * d : functionDecl->type->parameters ) {
461 if ( ObjectDecl * obj = dynamic_cast< ObjectDecl * >( d ) ) {
462 if ( SingleInit * init = dynamic_cast< SingleInit * >( obj->init ) ) {
463 delete init->value->env;
464 init->value->env = nullptr;
465 }
466 }
467 }
468 }
469
470 void Resolver_old::previsit( EnumDecl * ) {
471 // in case we decide to allow nested enums
472 GuardValue( inEnumDecl );
473 inEnumDecl = true;
474 }
475
476 void Resolver_old::previsit( StaticAssertDecl * assertDecl ) {
477 findIntegralExpression( assertDecl->condition, indexer );
478 }
479
480 void Resolver_old::previsit( ExprStmt * exprStmt ) {
481 visit_children = false;
482 assertf( exprStmt->expr, "ExprStmt has null Expression in resolver" );
483 findVoidExpression( exprStmt->expr, indexer );
484 }
485
486 void Resolver_old::previsit( AsmExpr * asmExpr ) {
487 visit_children = false;
488 findVoidExpression( asmExpr->operand, indexer );
489 }
490
491 void Resolver_old::previsit( AsmStmt * asmStmt ) {
492 visit_children = false;
493 acceptAll( asmStmt->get_input(), *visitor );
494 acceptAll( asmStmt->get_output(), *visitor );
495 }
496
497 void Resolver_old::previsit( IfStmt * ifStmt ) {
498 findIntegralExpression( ifStmt->condition, indexer );
499 }
500
501 void Resolver_old::previsit( WhileStmt * whileStmt ) {
502 findIntegralExpression( whileStmt->condition, indexer );
503 }
504
505 void Resolver_old::previsit( ForStmt * forStmt ) {
506 if ( forStmt->condition ) {
507 findIntegralExpression( forStmt->condition, indexer );
508 } // if
509
510 if ( forStmt->increment ) {
511 findVoidExpression( forStmt->increment, indexer );
512 } // if
513 }
514
515 void Resolver_old::previsit( SwitchStmt * switchStmt ) {
516 GuardValue( currentObject );
517 findIntegralExpression( switchStmt->condition, indexer );
518
519 currentObject = CurrentObject( switchStmt->condition->result );
520 }
521
522 void Resolver_old::previsit( CaseStmt * caseStmt ) {
523 if ( caseStmt->condition ) {
524 std::list< InitAlternative > initAlts = currentObject.getOptions();
525 assertf( initAlts.size() == 1, "SwitchStmt did not correctly resolve an integral expression." );
526 // must remove cast from case statement because RangeExpr cannot be cast.
527 Expression * newExpr = new CastExpr( caseStmt->condition, initAlts.front().type->clone() );
528 findSingleExpression( newExpr, indexer );
529 // case condition cannot have a cast in C, so it must be removed, regardless of whether it performs a conversion.
530 // Ideally we would perform the conversion internally here.
531 if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( newExpr ) ) {
532 newExpr = castExpr->arg;
533 castExpr->arg = nullptr;
534 std::swap( newExpr->env, castExpr->env );
535 delete castExpr;
536 }
537 caseStmt->condition = newExpr;
538 }
539 }
540
541 void Resolver_old::previsit( BranchStmt * branchStmt ) {
542 visit_children = false;
543 // must resolve the argument for a computed goto
544 if ( branchStmt->get_type() == BranchStmt::Goto ) { // check for computed goto statement
545 if ( branchStmt->computedTarget ) {
546 // computed goto argument is void *
547 findSingleExpression( branchStmt->computedTarget, new PointerType( Type::Qualifiers(), new VoidType( Type::Qualifiers() ) ), indexer );
548 } // if
549 } // if
550 }
551
552 void Resolver_old::previsit( ReturnStmt * returnStmt ) {
553 visit_children = false;
554 if ( returnStmt->expr ) {
555 findSingleExpression( returnStmt->expr, functionReturn->clone(), indexer );
556 } // if
557 }
558
559 void Resolver_old::previsit( ThrowStmt * throwStmt ) {
560 visit_children = false;
561 // TODO: Replace *exception type with &exception type.
562 if ( throwStmt->get_expr() ) {
563 const StructDecl * exception_decl = indexer.lookupStruct( "__cfaehm_base_exception_t" );
564 assert( exception_decl );
565 Type * exceptType = new PointerType( noQualifiers, new StructInstType( noQualifiers, const_cast<StructDecl *>(exception_decl) ) );
566 findSingleExpression( throwStmt->expr, exceptType, indexer );
567 }
568 }
569
570 void Resolver_old::previsit( CatchStmt * catchStmt ) {
571 // Until we are very sure this invarent (ifs that move between passes have thenPart)
572 // holds, check it. This allows a check for when to decode the mangling.
573 if ( IfStmt * ifStmt = dynamic_cast<IfStmt *>( catchStmt->body ) ) {
574 assert( ifStmt->thenPart );
575 }
576 // Encode the catchStmt so the condition can see the declaration.
577 if ( catchStmt->cond ) {
578 IfStmt * ifStmt = new IfStmt( catchStmt->cond, nullptr, catchStmt->body );
579 catchStmt->cond = nullptr;
580 catchStmt->body = ifStmt;
581 }
582 }
583
584 void Resolver_old::postvisit( CatchStmt * catchStmt ) {
585 // Decode the catchStmt so everything is stored properly.
586 IfStmt * ifStmt = dynamic_cast<IfStmt *>( catchStmt->body );
587 if ( nullptr != ifStmt && nullptr == ifStmt->thenPart ) {
588 assert( ifStmt->condition );
589 assert( ifStmt->elsePart );
590 catchStmt->cond = ifStmt->condition;
591 catchStmt->body = ifStmt->elsePart;
592 ifStmt->condition = nullptr;
593 ifStmt->elsePart = nullptr;
594 delete ifStmt;
595 }
596 }
597
598 template< typename iterator_t >
599 inline bool advance_to_mutex( iterator_t & it, const iterator_t & end ) {
600 while( it != end && !(*it)->get_type()->get_mutex() ) {
601 it++;
602 }
603
604 return it != end;
605 }
606
607 void Resolver_old::previsit( WaitForStmt * stmt ) {
608 visit_children = false;
609
610 // Resolve all clauses first
611 for( auto& clause : stmt->clauses ) {
612
613 TypeEnvironment env;
614 AlternativeFinder funcFinder( indexer, env );
615
616 // Find all alternatives for a function in canonical form
617 funcFinder.findWithAdjustment( clause.target.function );
618
619 if ( funcFinder.get_alternatives().empty() ) {
620 stringstream ss;
621 ss << "Use of undeclared indentifier '";
622 ss << strict_dynamic_cast<NameExpr*>( clause.target.function )->name;
623 ss << "' in call to waitfor";
624 SemanticError( stmt->location, ss.str() );
625 }
626
627 if(clause.target.arguments.empty()) {
628 SemanticError( stmt->location, "Waitfor clause must have at least one mutex parameter");
629 }
630
631 // Find all alternatives for all arguments in canonical form
632 std::vector< AlternativeFinder > argAlternatives;
633 funcFinder.findSubExprs( clause.target.arguments.begin(), clause.target.arguments.end(), back_inserter( argAlternatives ) );
634
635 // List all combinations of arguments
636 std::vector< AltList > possibilities;
637 combos( argAlternatives.begin(), argAlternatives.end(), back_inserter( possibilities ) );
638
639 AltList func_candidates;
640 std::vector< AltList > args_candidates;
641
642 // For every possible function :
643 // try matching the arguments to the parameters
644 // not the other way around because we have more arguments than parameters
645 SemanticErrorException errors;
646 for ( Alternative & func : funcFinder.get_alternatives() ) {
647 try {
648 PointerType * pointer = dynamic_cast< PointerType* >( func.expr->get_result()->stripReferences() );
649 if( !pointer ) {
650 SemanticError( func.expr->get_result(), "candidate not viable: not a pointer type\n" );
651 }
652
653 FunctionType * function = dynamic_cast< FunctionType* >( pointer->get_base() );
654 if( !function ) {
655 SemanticError( pointer->get_base(), "candidate not viable: not a function type\n" );
656 }
657
658
659 {
660 auto param = function->parameters.begin();
661 auto param_end = function->parameters.end();
662
663 if( !advance_to_mutex( param, param_end ) ) {
664 SemanticError(function, "candidate function not viable: no mutex parameters\n");
665 }
666 }
667
668 Alternative newFunc( func );
669 // Strip reference from function
670 referenceToRvalueConversion( newFunc.expr, newFunc.cost );
671
672 // For all the set of arguments we have try to match it with the parameter of the current function alternative
673 for ( auto & argsList : possibilities ) {
674
675 try {
676 // Declare data structures need for resolution
677 OpenVarSet openVars;
678 AssertionSet resultNeed, resultHave;
679 TypeEnvironment resultEnv( func.env );
680 makeUnifiableVars( function, openVars, resultNeed );
681 // add all type variables as open variables now so that those not used in the parameter
682 // list are still considered open.
683 resultEnv.add( function->forall );
684
685 // Load type variables from arguemnts into one shared space
686 simpleCombineEnvironments( argsList.begin(), argsList.end(), resultEnv );
687
688 // Make sure we don't widen any existing bindings
689 resultEnv.forbidWidening();
690
691 // Find any unbound type variables
692 resultEnv.extractOpenVars( openVars );
693
694 auto param = function->parameters.begin();
695 auto param_end = function->parameters.end();
696
697 int n_mutex_param = 0;
698
699 // For every arguments of its set, check if it matches one of the parameter
700 // The order is important
701 for( auto & arg : argsList ) {
702
703 // Ignore non-mutex arguments
704 if( !advance_to_mutex( param, param_end ) ) {
705 // We ran out of parameters but still have arguments
706 // this function doesn't match
707 SemanticError( function, toString("candidate function not viable: too many mutex arguments, expected ", n_mutex_param, "\n" ));
708 }
709
710 n_mutex_param++;
711
712 // Check if the argument matches the parameter type in the current scope
713 if( ! unify( arg.expr->get_result(), (*param)->get_type(), resultEnv, resultNeed, resultHave, openVars, this->indexer ) ) {
714 // Type doesn't match
715 stringstream ss;
716 ss << "candidate function not viable: no known convertion from '";
717 (*param)->get_type()->print( ss );
718 ss << "' to '";
719 arg.expr->get_result()->print( ss );
720 ss << "' with env '";
721 resultEnv.print(ss);
722 ss << "'\n";
723 SemanticError( function, ss.str() );
724 }
725
726 param++;
727 }
728
729 // All arguments match !
730
731 // Check if parameters are missing
732 if( advance_to_mutex( param, param_end ) ) {
733 do {
734 n_mutex_param++;
735 param++;
736 } while( advance_to_mutex( param, param_end ) );
737
738 // We ran out of arguments but still have parameters left
739 // this function doesn't match
740 SemanticError( function, toString("candidate function not viable: too few mutex arguments, expected ", n_mutex_param, "\n" ));
741 }
742
743 // All parameters match !
744
745 // Finish the expressions to tie in the proper environments
746 finishExpr( newFunc.expr, resultEnv );
747 for( Alternative & alt : argsList ) {
748 finishExpr( alt.expr, resultEnv );
749 }
750
751 // This is a match store it and save it for later
752 func_candidates.push_back( newFunc );
753 args_candidates.push_back( argsList );
754
755 }
756 catch( SemanticErrorException & e ) {
757 errors.append( e );
758 }
759 }
760 }
761 catch( SemanticErrorException & e ) {
762 errors.append( e );
763 }
764 }
765
766 // Make sure we got the right number of arguments
767 if( func_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for function in call to waitfor" ); top.append( errors ); throw top; }
768 if( args_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for arguments in call to waitfor" ); top.append( errors ); throw top; }
769 if( func_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous function in call to waitfor" ); top.append( errors ); throw top; }
770 if( args_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous arguments in call to waitfor" ); top.append( errors ); throw top; }
771 // TODO: need to use findDeletedExpr to ensure no deleted identifiers are used.
772
773 // Swap the results from the alternative with the unresolved values.
774 // Alternatives will handle deletion on destruction
775 std::swap( clause.target.function, func_candidates.front().expr );
776 for( auto arg_pair : group_iterate( clause.target.arguments, args_candidates.front() ) ) {
777 std::swap ( std::get<0>( arg_pair), std::get<1>( arg_pair).expr );
778 }
779
780 // Resolve the conditions as if it were an IfStmt
781 // Resolve the statments normally
782 findSingleExpression( clause.condition, this->indexer );
783 clause.statement->accept( *visitor );
784 }
785
786
787 if( stmt->timeout.statement ) {
788 // Resolve the timeout as an size_t for now
789 // Resolve the conditions as if it were an IfStmt
790 // Resolve the statments normally
791 findSingleExpression( stmt->timeout.time, new BasicType( noQualifiers, BasicType::LongLongUnsignedInt ), this->indexer );
792 findSingleExpression( stmt->timeout.condition, this->indexer );
793 stmt->timeout.statement->accept( *visitor );
794 }
795
796 if( stmt->orelse.statement ) {
797 // Resolve the conditions as if it were an IfStmt
798 // Resolve the statments normally
799 findSingleExpression( stmt->orelse.condition, this->indexer );
800 stmt->orelse.statement->accept( *visitor );
801 }
802 }
803
804 bool isCharType( Type * t ) {
805 if ( BasicType * bt = dynamic_cast< BasicType * >( t ) ) {
806 return bt->get_kind() == BasicType::Char || bt->get_kind() == BasicType::SignedChar ||
807 bt->get_kind() == BasicType::UnsignedChar;
808 }
809 return false;
810 }
811
812 void Resolver_old::previsit( SingleInit * singleInit ) {
813 visit_children = false;
814 // resolve initialization using the possibilities as determined by the currentObject cursor
815 Expression * newExpr = new UntypedInitExpr( singleInit->value, currentObject.getOptions() );
816 findSingleExpression( newExpr, indexer );
817 InitExpr * initExpr = strict_dynamic_cast< InitExpr * >( newExpr );
818
819 // move cursor to the object that is actually initialized
820 currentObject.setNext( initExpr->get_designation() );
821
822 // discard InitExpr wrapper and retain relevant pieces
823 newExpr = initExpr->expr;
824 initExpr->expr = nullptr;
825 std::swap( initExpr->env, newExpr->env );
826 // InitExpr may have inferParams in the case where the expression specializes a function
827 // pointer, and newExpr may already have inferParams of its own, so a simple swap is not
828 // sufficient.
829 newExpr->spliceInferParams( initExpr );
830 delete initExpr;
831
832 // get the actual object's type (may not exactly match what comes back from the resolver
833 // due to conversions)
834 Type * initContext = currentObject.getCurrentType();
835
836 removeExtraneousCast( newExpr, indexer );
837
838 // check if actual object's type is char[]
839 if ( ArrayType * at = dynamic_cast< ArrayType * >( initContext ) ) {
840 if ( isCharType( at->get_base() ) ) {
841 // check if the resolved type is char *
842 if ( PointerType * pt = dynamic_cast< PointerType *>( newExpr->get_result() ) ) {
843 if ( isCharType( pt->get_base() ) ) {
844 if ( CastExpr * ce = dynamic_cast< CastExpr * >( newExpr ) ) {
845 // strip cast if we're initializing a char[] with a char *,
846 // e.g. char x[] = "hello";
847 newExpr = ce->get_arg();
848 ce->set_arg( nullptr );
849 std::swap( ce->env, newExpr->env );
850 delete ce;
851 }
852 }
853 }
854 }
855 }
856
857 // set initializer expr to resolved express
858 singleInit->value = newExpr;
859
860 // move cursor to next object in preparation for next initializer
861 currentObject.increment();
862 }
863
864 void Resolver_old::previsit( ListInit * listInit ) {
865 visit_children = false;
866 // move cursor into brace-enclosed initializer-list
867 currentObject.enterListInit();
868 // xxx - fix this so that the list isn't copied, iterator should be used to change current
869 // element
870 std::list<Designation *> newDesignations;
871 for ( auto p : group_iterate(listInit->get_designations(), listInit->get_initializers()) ) {
872 // iterate designations and initializers in pairs, moving the cursor to the current
873 // designated object and resolving the initializer against that object.
874 Designation * des = std::get<0>(p);
875 Initializer * init = std::get<1>(p);
876 newDesignations.push_back( currentObject.findNext( des ) );
877 init->accept( *visitor );
878 }
879 // set the set of 'resolved' designations and leave the brace-enclosed initializer-list
880 listInit->get_designations() = newDesignations; // xxx - memory management
881 currentObject.exitListInit();
882
883 // xxx - this part has not be folded into CurrentObject yet
884 // } else if ( TypeInstType * tt = dynamic_cast< TypeInstType * >( initContext ) ) {
885 // Type * base = tt->get_baseType()->get_base();
886 // if ( base ) {
887 // // know the implementation type, so try using that as the initContext
888 // ObjectDecl tmpObj( "", Type::StorageClasses(), LinkageSpec::Cforall, nullptr, base->clone(), nullptr );
889 // currentObject = &tmpObj;
890 // visit( listInit );
891 // } else {
892 // // missing implementation type -- might be an unknown type variable, so try proceeding with the current init context
893 // Parent::visit( listInit );
894 // }
895 // } else {
896 }
897
898 // ConstructorInit - fall back on C-style initializer
899 void Resolver_old::fallbackInit( ConstructorInit * ctorInit ) {
900 // could not find valid constructor, or found an intrinsic constructor
901 // fall back on C-style initializer
902 delete ctorInit->get_ctor();
903 ctorInit->set_ctor( nullptr );
904 delete ctorInit->get_dtor();
905 ctorInit->set_dtor( nullptr );
906 maybeAccept( ctorInit->get_init(), *visitor );
907 }
908
909 // needs to be callable from outside the resolver, so this is a standalone function
910 void resolveCtorInit( ConstructorInit * ctorInit, const SymTab::Indexer & indexer ) {
911 assert( ctorInit );
912 PassVisitor<Resolver_old> resolver( indexer );
913 ctorInit->accept( resolver );
914 }
915
916 void resolveStmtExpr( StmtExpr * stmtExpr, const SymTab::Indexer & indexer ) {
917 assert( stmtExpr );
918 PassVisitor<Resolver_old> resolver( indexer );
919 stmtExpr->accept( resolver );
920 stmtExpr->computeResult();
921 // xxx - aggregate the environments from all statements? Possibly in AlternativeFinder instead?
922 }
923
924 void Resolver_old::previsit( ConstructorInit * ctorInit ) {
925 visit_children = false;
926 // xxx - fallback init has been removed => remove fallbackInit function and remove complexity from FixInit and remove C-init from ConstructorInit
927 maybeAccept( ctorInit->ctor, *visitor );
928 maybeAccept( ctorInit->dtor, *visitor );
929
930 // found a constructor - can get rid of C-style initializer
931 delete ctorInit->init;
932 ctorInit->init = nullptr;
933
934 // intrinsic single parameter constructors and destructors do nothing. Since this was
935 // implicitly generated, there's no way for it to have side effects, so get rid of it
936 // to clean up generated code.
937 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->ctor ) ) {
938 delete ctorInit->ctor;
939 ctorInit->ctor = nullptr;
940 }
941
942 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->dtor ) ) {
943 delete ctorInit->dtor;
944 ctorInit->dtor = nullptr;
945 }
946
947 // xxx - todo -- what about arrays?
948 // if ( dtor == nullptr && InitTweak::isIntrinsicCallStmt( ctorInit->get_ctor() ) ) {
949 // // can reduce the constructor down to a SingleInit using the
950 // // second argument from the ctor call, since
951 // delete ctorInit->get_ctor();
952 // ctorInit->set_ctor( nullptr );
953
954 // Expression * arg =
955 // ctorInit->set_init( new SingleInit( arg ) );
956 // }
957 }
958
959 ///////////////////////////////////////////////////////////////////////////
960 //
961 // *** NEW RESOLVER ***
962 //
963 ///////////////////////////////////////////////////////////////////////////
964
965 namespace {
966 /// Finds deleted expressions in an expression tree
967 struct DeleteFinder_new final : public ast::WithShortCircuiting {
968 const ast::DeletedExpr * result = nullptr;
969
970 void previsit( const ast::DeletedExpr * expr ) {
971 if ( result ) { visit_children = false; }
972 else { result = expr; }
973 }
974
975 void previsit( const ast::Expr * ) {
976 if ( result ) { visit_children = false; }
977 }
978 };
979 } // anonymous namespace
980
981 /// Check if this expression is or includes a deleted expression
982 const ast::DeletedExpr * findDeletedExpr( const ast::Expr * expr ) {
983 return ast::Pass<DeleteFinder_new>::read( expr );
984 }
985
986 namespace {
987 /// always-accept candidate filter
988 bool anyCandidate( const Candidate & ) { return true; }
989
990 /// Calls the CandidateFinder and finds the single best candidate
991 CandidateRef findUnfinishedKindExpression(
992 const ast::Expr * untyped, const ast::SymbolTable & symtab, const std::string & kind,
993 std::function<bool(const Candidate &)> pred = anyCandidate, ResolvMode mode = {}
994 ) {
995 if ( ! untyped ) return nullptr;
996
997 // xxx - this isn't thread-safe, but should work until we parallelize the resolver
998 static unsigned recursion_level = 0;
999
1000 ++recursion_level;
1001 ast::TypeEnvironment env;
1002 CandidateFinder finder{ symtab, env };
1003 finder.find( untyped, recursion_level == 1 ? mode.atTopLevel() : mode );
1004 --recursion_level;
1005
1006 // produce a filtered list of candidates
1007 CandidateList candidates;
1008 for ( auto & cand : finder.candidates ) {
1009 if ( pred( *cand ) ) { candidates.emplace_back( cand ); }
1010 }
1011
1012 // produce invalid error if no candidates
1013 if ( candidates.empty() ) {
1014 SemanticError( untyped,
1015 toString( "No reasonable alternatives for ", kind, (kind != "" ? " " : ""),
1016 "expression: ") );
1017 }
1018
1019 // search for cheapest candidate
1020 CandidateList winners;
1021 bool seen_undeleted = false;
1022 for ( CandidateRef & cand : candidates ) {
1023 int c = winners.empty() ? -1 : cand->cost.compare( winners.front()->cost );
1024
1025 if ( c > 0 ) continue; // skip more expensive than winner
1026
1027 if ( c < 0 ) {
1028 // reset on new cheapest
1029 seen_undeleted = ! findDeletedExpr( cand->expr );
1030 winners.clear();
1031 } else /* if ( c == 0 ) */ {
1032 if ( findDeletedExpr( cand->expr ) ) {
1033 // skip deleted expression if already seen one equivalent-cost not
1034 if ( seen_undeleted ) continue;
1035 } else if ( ! seen_undeleted ) {
1036 // replace list of equivalent-cost deleted expressions with one non-deleted
1037 winners.clear();
1038 seen_undeleted = true;
1039 }
1040 }
1041
1042 winners.emplace_back( std::move( cand ) );
1043 }
1044
1045 // promote candidate.cvtCost to .cost
1046 promoteCvtCost( winners );
1047
1048 // produce ambiguous errors, if applicable
1049 if ( winners.size() != 1 ) {
1050 std::ostringstream stream;
1051 stream << "Cannot choose between " << winners.size() << " alternatives for "
1052 << kind << (kind != "" ? " " : "") << "expression\n";
1053 ast::print( stream, untyped );
1054 stream << " Alternatives are:\n";
1055 print( stream, winners, 1 );
1056 SemanticError( untyped->location, stream.str() );
1057 }
1058
1059 // single selected choice
1060 CandidateRef & choice = winners.front();
1061
1062 // fail on only expression deleted
1063 if ( ! seen_undeleted ) {
1064 SemanticError( untyped->location, choice->expr.get(), "Unique best alternative "
1065 "includes deleted identifier in " );
1066 }
1067
1068 return std::move( choice );
1069 }
1070
1071 /// Strips extraneous casts out of an expression
1072 struct StripCasts_new final {
1073 const ast::Expr * postvisit( const ast::CastExpr * castExpr ) {
1074 if (
1075 castExpr->isGenerated == ast::GeneratedCast
1076 && typesCompatible( castExpr->arg->result, castExpr->result )
1077 ) {
1078 // generated cast is the same type as its argument, remove it after keeping env
1079 return ast::mutate_field(
1080 castExpr->arg.get(), &ast::Expr::env, castExpr->env );
1081 }
1082 return castExpr;
1083 }
1084
1085 static void strip( ast::ptr< ast::Expr > & expr ) {
1086 ast::Pass< StripCasts_new > stripper;
1087 expr = expr->accept( stripper );
1088 }
1089 };
1090
1091 /// Swaps argument into expression pointer, saving original environment
1092 void swap_and_save_env( ast::ptr< ast::Expr > & expr, const ast::Expr * newExpr ) {
1093 ast::ptr< ast::TypeSubstitution > env = expr->env;
1094 expr.set_and_mutate( newExpr )->env = env;
1095 }
1096
1097 /// Removes cast to type of argument (unlike StripCasts, also handles non-generated casts)
1098 void removeExtraneousCast( ast::ptr<ast::Expr> & expr, const ast::SymbolTable & symtab ) {
1099 if ( const ast::CastExpr * castExpr = expr.as< ast::CastExpr >() ) {
1100 if ( typesCompatible( castExpr->arg->result, castExpr->result, symtab ) ) {
1101 // cast is to the same type as its argument, remove it
1102 swap_and_save_env( expr, castExpr->arg );
1103 }
1104 }
1105 }
1106
1107 /// Establish post-resolver invariants for expressions
1108 void finishExpr(
1109 ast::ptr< ast::Expr > & expr, const ast::TypeEnvironment & env,
1110 const ast::TypeSubstitution * oldenv = nullptr
1111 ) {
1112 // set up new type substitution for expression
1113 ast::ptr< ast::TypeSubstitution > newenv =
1114 oldenv ? oldenv : new ast::TypeSubstitution{};
1115 env.writeToSubstitution( *newenv.get_and_mutate() );
1116 expr.get_and_mutate()->env = std::move( newenv );
1117 // remove unncecessary casts
1118 StripCasts_new::strip( expr );
1119 }
1120 } // anonymous namespace
1121
1122
1123 ast::ptr< ast::Expr > resolveInVoidContext(
1124 const ast::Expr * expr, const ast::SymbolTable & symtab, ast::TypeEnvironment & env
1125 ) {
1126 assertf( expr, "expected a non-null expression" );
1127
1128 // set up and resolve expression cast to void
1129 ast::ptr< ast::CastExpr > untyped = new ast::CastExpr{ expr };
1130 CandidateRef choice = findUnfinishedKindExpression(
1131 untyped, symtab, "", anyCandidate, ResolvMode::withAdjustment() );
1132
1133 // a cast expression has either 0 or 1 interpretations (by language rules);
1134 // if 0, an exception has already been thrown, and this code will not run
1135 const ast::CastExpr * castExpr = choice->expr.strict_as< ast::CastExpr >();
1136 env = std::move( choice->env );
1137
1138 return castExpr->arg;
1139 }
1140
1141 namespace {
1142 /// Resolve `untyped` to the expression whose candidate is the best match for a `void`
1143 /// context.
1144 ast::ptr< ast::Expr > findVoidExpression(
1145 const ast::Expr * untyped, const ast::SymbolTable & symtab
1146 ) {
1147 resetTyVarRenaming();
1148 ast::TypeEnvironment env;
1149 ast::ptr< ast::Expr > newExpr = resolveInVoidContext( untyped, symtab, env );
1150 finishExpr( newExpr, env, untyped->env );
1151 return newExpr;
1152 }
1153
1154 /// resolve `untyped` to the expression whose candidate satisfies `pred` with the
1155 /// lowest cost, returning the resolved version
1156 ast::ptr< ast::Expr > findKindExpression(
1157 const ast::Expr * untyped, const ast::SymbolTable & symtab,
1158 std::function<bool(const Candidate &)> pred = anyCandidate,
1159 const std::string & kind = "", ResolvMode mode = {}
1160 ) {
1161 if ( ! untyped ) return {};
1162 CandidateRef choice =
1163 findUnfinishedKindExpression( untyped, symtab, kind, pred, mode );
1164 finishExpr( choice->expr, choice->env, untyped->env );
1165 return std::move( choice->expr );
1166 }
1167
1168 /// Resolve `untyped` to the single expression whose candidate is the best match
1169 ast::ptr< ast::Expr > findSingleExpression(
1170 const ast::Expr * untyped, const ast::SymbolTable & symtab
1171 ) {
1172 Stats::ResolveTime::start( untyped );
1173 auto res = findKindExpression( untyped, symtab );
1174 Stats::ResolveTime::stop();
1175 return res;
1176 }
1177 } // anonymous namespace
1178
1179 ast::ptr< ast::Expr > findSingleExpression(
1180 const ast::Expr * untyped, const ast::Type * type, const ast::SymbolTable & symtab
1181 ) {
1182 assert( untyped && type );
1183 ast::ptr< ast::Expr > castExpr = new ast::CastExpr{ untyped, type };
1184 ast::ptr< ast::Expr > newExpr = findSingleExpression( castExpr, symtab );
1185 removeExtraneousCast( newExpr, symtab );
1186 return newExpr;
1187 }
1188
1189 namespace {
1190 /// Predicate for "Candidate has integral type"
1191 bool hasIntegralType( const Candidate & i ) {
1192 const ast::Type * type = i.expr->result;
1193
1194 if ( auto bt = dynamic_cast< const ast::BasicType * >( type ) ) {
1195 return bt->isInteger();
1196 } else if (
1197 dynamic_cast< const ast::EnumInstType * >( type )
1198 || dynamic_cast< const ast::ZeroType * >( type )
1199 || dynamic_cast< const ast::OneType * >( type )
1200 ) {
1201 return true;
1202 } else return false;
1203 }
1204
1205 /// Resolve `untyped` as an integral expression, returning the resolved version
1206 ast::ptr< ast::Expr > findIntegralExpression(
1207 const ast::Expr * untyped, const ast::SymbolTable & symtab
1208 ) {
1209 return findKindExpression( untyped, symtab, hasIntegralType, "condition" );
1210 }
1211
1212 /// check if a type is a character type
1213 bool isCharType( const ast::Type * t ) {
1214 if ( auto bt = dynamic_cast< const ast::BasicType * >( t ) ) {
1215 return bt->kind == ast::BasicType::Char
1216 || bt->kind == ast::BasicType::SignedChar
1217 || bt->kind == ast::BasicType::UnsignedChar;
1218 }
1219 return false;
1220 }
1221
1222 /// Advance a type itertor to the next mutex parameter
1223 template<typename Iter>
1224 inline bool nextMutex( Iter & it, const Iter & end ) {
1225 while ( it != end && ! (*it)->get_type()->is_mutex() ) { ++it; }
1226 return it != end;
1227 }
1228 }
1229
1230 class Resolver_new final
1231 : public ast::WithSymbolTable, public ast::WithGuards,
1232 public ast::WithVisitorRef<Resolver_new>, public ast::WithShortCircuiting,
1233 public ast::WithStmtsToAdd<> {
1234
1235 ast::ptr< ast::Type > functionReturn = nullptr;
1236 ast::CurrentObject currentObject;
1237 bool inEnumDecl = false;
1238
1239 public:
1240 static size_t traceId;
1241 Resolver_new() = default;
1242 Resolver_new( const ast::SymbolTable & syms ) { symtab = syms; }
1243
1244 void previsit( const ast::FunctionDecl * );
1245 const ast::FunctionDecl * postvisit( const ast::FunctionDecl * );
1246 void previsit( const ast::ObjectDecl * );
1247 void previsit( const ast::EnumDecl * );
1248 const ast::StaticAssertDecl * previsit( const ast::StaticAssertDecl * );
1249
1250 const ast::ArrayType * previsit( const ast::ArrayType * );
1251 const ast::PointerType * previsit( const ast::PointerType * );
1252
1253 const ast::ExprStmt * previsit( const ast::ExprStmt * );
1254 const ast::AsmExpr * previsit( const ast::AsmExpr * );
1255 const ast::AsmStmt * previsit( const ast::AsmStmt * );
1256 const ast::IfStmt * previsit( const ast::IfStmt * );
1257 const ast::WhileStmt * previsit( const ast::WhileStmt * );
1258 const ast::ForStmt * previsit( const ast::ForStmt * );
1259 const ast::SwitchStmt * previsit( const ast::SwitchStmt * );
1260 const ast::CaseStmt * previsit( const ast::CaseStmt * );
1261 const ast::BranchStmt * previsit( const ast::BranchStmt * );
1262 const ast::ReturnStmt * previsit( const ast::ReturnStmt * );
1263 const ast::ThrowStmt * previsit( const ast::ThrowStmt * );
1264 const ast::CatchStmt * previsit( const ast::CatchStmt * );
1265 const ast::CatchStmt * postvisit( const ast::CatchStmt * );
1266 const ast::WaitForStmt * previsit( const ast::WaitForStmt * );
1267
1268 const ast::SingleInit * previsit( const ast::SingleInit * );
1269 const ast::ListInit * previsit( const ast::ListInit * );
1270 const ast::ConstructorInit * previsit( const ast::ConstructorInit * );
1271 };
1272 // size_t Resolver_new::traceId = Stats::Heap::new_stacktrace_id("Resolver");
1273
1274 void resolve( std::list< ast::ptr< ast::Decl > >& translationUnit ) {
1275 ast::Pass< Resolver_new >::run( translationUnit );
1276 }
1277
1278 ast::ptr< ast::Init > resolveCtorInit(
1279 const ast::ConstructorInit * ctorInit, const ast::SymbolTable & symtab
1280 ) {
1281 assert( ctorInit );
1282 ast::Pass< Resolver_new > resolver{ symtab };
1283 return ctorInit->accept( resolver );
1284 }
1285
1286 ast::ptr< ast::Expr > resolveStmtExpr(
1287 const ast::StmtExpr * stmtExpr, const ast::SymbolTable & symtab
1288 ) {
1289 assert( stmtExpr );
1290 ast::Pass< Resolver_new > resolver{ symtab };
1291 ast::ptr< ast::Expr > ret = stmtExpr;
1292 ret = ret->accept( resolver );
1293 strict_dynamic_cast< ast::StmtExpr * >( ret.get_and_mutate() )->computeResult();
1294 return ret;
1295 }
1296
1297 void Resolver_new::previsit( const ast::FunctionDecl * functionDecl ) {
1298 GuardValue( functionReturn );
1299 functionReturn = extractResultType( functionDecl->type );
1300 }
1301
1302 const ast::FunctionDecl * Resolver_new::postvisit( const ast::FunctionDecl * functionDecl ) {
1303 // default value expressions have an environment which shouldn't be there and trips up
1304 // later passes.
1305 assert( functionDecl->unique() );
1306 ast::FunctionType * mutType = mutate( functionDecl->type.get() );
1307
1308 for ( unsigned i = 0 ; i < mutType->params.size() ; ++i ) {
1309 if ( const ast::ObjectDecl * obj = mutType->params[i].as< ast::ObjectDecl >() ) {
1310 if ( const ast::SingleInit * init = obj->init.as< ast::SingleInit >() ) {
1311 if ( init->value->env == nullptr ) continue;
1312 // clone initializer minus the initializer environment
1313 auto mutParam = mutate( mutType->params[i].strict_as< ast::ObjectDecl >() );
1314 auto mutInit = mutate( mutParam->init.strict_as< ast::SingleInit >() );
1315 auto mutValue = mutate( mutInit->value.get() );
1316
1317 mutValue->env = nullptr;
1318 mutInit->value = mutValue;
1319 mutParam->init = mutInit;
1320 mutType->params[i] = mutParam;
1321
1322 assert( ! mutType->params[i].strict_as< ast::ObjectDecl >()->init.strict_as< ast::SingleInit >()->value->env);
1323 }
1324 }
1325 }
1326 mutate_field(functionDecl, &ast::FunctionDecl::type, mutType);
1327 return functionDecl;
1328 }
1329
1330 void Resolver_new::previsit( const ast::ObjectDecl * objectDecl ) {
1331 // To handle initialization of routine pointers [e.g. int (*fp)(int) = foo()],
1332 // class-variable `initContext` is changed multiple times because the LHS is analyzed
1333 // twice. The second analysis changes `initContext` because a function type can contain
1334 // object declarations in the return and parameter types. Therefore each value of
1335 // `initContext` is retained so the type on the first analysis is preserved and used for
1336 // selecting the RHS.
1337 GuardValue( currentObject );
1338 currentObject = ast::CurrentObject{ objectDecl->location, objectDecl->get_type() };
1339 if ( inEnumDecl && dynamic_cast< const ast::EnumInstType * >( objectDecl->get_type() ) ) {
1340 // enumerator initializers should not use the enum type to initialize, since the
1341 // enum type is still incomplete at this point. Use `int` instead.
1342 currentObject = ast::CurrentObject{
1343 objectDecl->location, new ast::BasicType{ ast::BasicType::SignedInt } };
1344 }
1345 }
1346
1347 void Resolver_new::previsit( const ast::EnumDecl * ) {
1348 // in case we decide to allow nested enums
1349 GuardValue( inEnumDecl );
1350 inEnumDecl = true;
1351 }
1352
1353 const ast::StaticAssertDecl * Resolver_new::previsit(
1354 const ast::StaticAssertDecl * assertDecl
1355 ) {
1356 return ast::mutate_field(
1357 assertDecl, &ast::StaticAssertDecl::cond,
1358 findIntegralExpression( assertDecl->cond, symtab ) );
1359 }
1360
1361 template< typename PtrType >
1362 const PtrType * handlePtrType( const PtrType * type, const ast::SymbolTable & symtab ) {
1363 if ( type->dimension ) {
1364 #warning should use new equivalent to Validate::SizeType rather than sizeType here
1365 ast::ptr< ast::Type > sizeType = new ast::BasicType{ ast::BasicType::LongUnsignedInt };
1366 ast::mutate_field(
1367 type, &PtrType::dimension,
1368 findSingleExpression( type->dimension, sizeType, symtab ) );
1369 }
1370 return type;
1371 }
1372
1373 const ast::ArrayType * Resolver_new::previsit( const ast::ArrayType * at ) {
1374 return handlePtrType( at, symtab );
1375 }
1376
1377 const ast::PointerType * Resolver_new::previsit( const ast::PointerType * pt ) {
1378 return handlePtrType( pt, symtab );
1379 }
1380
1381 const ast::ExprStmt * Resolver_new::previsit( const ast::ExprStmt * exprStmt ) {
1382 visit_children = false;
1383 assertf( exprStmt->expr, "ExprStmt has null expression in resolver" );
1384
1385 return ast::mutate_field(
1386 exprStmt, &ast::ExprStmt::expr, findVoidExpression( exprStmt->expr, symtab ) );
1387 }
1388
1389 const ast::AsmExpr * Resolver_new::previsit( const ast::AsmExpr * asmExpr ) {
1390 visit_children = false;
1391
1392 asmExpr = ast::mutate_field(
1393 asmExpr, &ast::AsmExpr::operand, findVoidExpression( asmExpr->operand, symtab ) );
1394
1395 return asmExpr;
1396 }
1397
1398 const ast::AsmStmt * Resolver_new::previsit( const ast::AsmStmt * asmStmt ) {
1399 visitor->maybe_accept( asmStmt, &ast::AsmStmt::input );
1400 visitor->maybe_accept( asmStmt, &ast::AsmStmt::output );
1401 visit_children = false;
1402 return asmStmt;
1403 }
1404
1405 const ast::IfStmt * Resolver_new::previsit( const ast::IfStmt * ifStmt ) {
1406 return ast::mutate_field(
1407 ifStmt, &ast::IfStmt::cond, findIntegralExpression( ifStmt->cond, symtab ) );
1408 }
1409
1410 const ast::WhileStmt * Resolver_new::previsit( const ast::WhileStmt * whileStmt ) {
1411 return ast::mutate_field(
1412 whileStmt, &ast::WhileStmt::cond, findIntegralExpression( whileStmt->cond, symtab ) );
1413 }
1414
1415 const ast::ForStmt * Resolver_new::previsit( const ast::ForStmt * forStmt ) {
1416 if ( forStmt->cond ) {
1417 forStmt = ast::mutate_field(
1418 forStmt, &ast::ForStmt::cond, findIntegralExpression( forStmt->cond, symtab ) );
1419 }
1420
1421 if ( forStmt->inc ) {
1422 forStmt = ast::mutate_field(
1423 forStmt, &ast::ForStmt::inc, findVoidExpression( forStmt->inc, symtab ) );
1424 }
1425
1426 return forStmt;
1427 }
1428
1429 const ast::SwitchStmt * Resolver_new::previsit( const ast::SwitchStmt * switchStmt ) {
1430 GuardValue( currentObject );
1431 switchStmt = ast::mutate_field(
1432 switchStmt, &ast::SwitchStmt::cond,
1433 findIntegralExpression( switchStmt->cond, symtab ) );
1434 currentObject = ast::CurrentObject{ switchStmt->location, switchStmt->cond->result };
1435 return switchStmt;
1436 }
1437
1438 const ast::CaseStmt * Resolver_new::previsit( const ast::CaseStmt * caseStmt ) {
1439 if ( caseStmt->cond ) {
1440 std::deque< ast::InitAlternative > initAlts = currentObject.getOptions();
1441 assertf( initAlts.size() == 1, "SwitchStmt did not correctly resolve an integral "
1442 "expression." );
1443
1444 ast::ptr< ast::Expr > untyped =
1445 new ast::CastExpr{ caseStmt->location, caseStmt->cond, initAlts.front().type };
1446 ast::ptr< ast::Expr > newExpr = findSingleExpression( untyped, symtab );
1447
1448 // case condition cannot have a cast in C, so it must be removed here, regardless of
1449 // whether it would perform a conversion.
1450 if ( const ast::CastExpr * castExpr = newExpr.as< ast::CastExpr >() ) {
1451 swap_and_save_env( newExpr, castExpr->arg );
1452 }
1453
1454 caseStmt = ast::mutate_field( caseStmt, &ast::CaseStmt::cond, newExpr );
1455 }
1456 return caseStmt;
1457 }
1458
1459 const ast::BranchStmt * Resolver_new::previsit( const ast::BranchStmt * branchStmt ) {
1460 visit_children = false;
1461 // must resolve the argument of a computed goto
1462 if ( branchStmt->kind == ast::BranchStmt::Goto && branchStmt->computedTarget ) {
1463 // computed goto argument is void*
1464 ast::ptr< ast::Type > target = new ast::PointerType{ new ast::VoidType{} };
1465 branchStmt = ast::mutate_field(
1466 branchStmt, &ast::BranchStmt::computedTarget,
1467 findSingleExpression( branchStmt->computedTarget, target, symtab ) );
1468 }
1469 return branchStmt;
1470 }
1471
1472 const ast::ReturnStmt * Resolver_new::previsit( const ast::ReturnStmt * returnStmt ) {
1473 visit_children = false;
1474 if ( returnStmt->expr ) {
1475 returnStmt = ast::mutate_field(
1476 returnStmt, &ast::ReturnStmt::expr,
1477 findSingleExpression( returnStmt->expr, functionReturn, symtab ) );
1478 }
1479 return returnStmt;
1480 }
1481
1482 const ast::ThrowStmt * Resolver_new::previsit( const ast::ThrowStmt * throwStmt ) {
1483 visit_children = false;
1484 if ( throwStmt->expr ) {
1485 const ast::StructDecl * exceptionDecl =
1486 symtab.lookupStruct( "__cfaehm_base_exception_t" );
1487 assert( exceptionDecl );
1488 ast::ptr< ast::Type > exceptType =
1489 new ast::PointerType{ new ast::StructInstType{ exceptionDecl } };
1490 throwStmt = ast::mutate_field(
1491 throwStmt, &ast::ThrowStmt::expr,
1492 findSingleExpression( throwStmt->expr, exceptType, symtab ) );
1493 }
1494 return throwStmt;
1495 }
1496
1497 const ast::CatchStmt * Resolver_new::previsit( const ast::CatchStmt * catchStmt ) {
1498 // Until we are very sure this invarent (ifs that move between passes have thenPart)
1499 // holds, check it. This allows a check for when to decode the mangling.
1500 if ( auto ifStmt = catchStmt->body.as<ast::IfStmt>() ) {
1501 assert( ifStmt->thenPart );
1502 }
1503 // Encode the catchStmt so the condition can see the declaration.
1504 if ( catchStmt->cond ) {
1505 ast::CatchStmt * stmt = mutate( catchStmt );
1506 stmt->body = new ast::IfStmt( stmt->location, stmt->cond, nullptr, stmt->body );
1507 stmt->cond = nullptr;
1508 return stmt;
1509 }
1510 return catchStmt;
1511 }
1512
1513 const ast::CatchStmt * Resolver_new::postvisit( const ast::CatchStmt * catchStmt ) {
1514 // Decode the catchStmt so everything is stored properly.
1515 const ast::IfStmt * ifStmt = catchStmt->body.as<ast::IfStmt>();
1516 if ( nullptr != ifStmt && nullptr == ifStmt->thenPart ) {
1517 assert( ifStmt->cond );
1518 assert( ifStmt->elsePart );
1519 ast::CatchStmt * stmt = ast::mutate( catchStmt );
1520 stmt->cond = ifStmt->cond;
1521 stmt->body = ifStmt->elsePart;
1522 // ifStmt should be implicately deleted here.
1523 return stmt;
1524 }
1525 return catchStmt;
1526 }
1527
1528 const ast::WaitForStmt * Resolver_new::previsit( const ast::WaitForStmt * stmt ) {
1529 visit_children = false;
1530
1531 // Resolve all clauses first
1532 for ( unsigned i = 0; i < stmt->clauses.size(); ++i ) {
1533 const ast::WaitForStmt::Clause & clause = stmt->clauses[i];
1534
1535 ast::TypeEnvironment env;
1536 CandidateFinder funcFinder{ symtab, env };
1537
1538 // Find all candidates for a function in canonical form
1539 funcFinder.find( clause.target.func, ResolvMode::withAdjustment() );
1540
1541 if ( funcFinder.candidates.empty() ) {
1542 stringstream ss;
1543 ss << "Use of undeclared indentifier '";
1544 ss << clause.target.func.strict_as< ast::NameExpr >()->name;
1545 ss << "' in call to waitfor";
1546 SemanticError( stmt->location, ss.str() );
1547 }
1548
1549 if ( clause.target.args.empty() ) {
1550 SemanticError( stmt->location,
1551 "Waitfor clause must have at least one mutex parameter");
1552 }
1553
1554 // Find all alternatives for all arguments in canonical form
1555 std::vector< CandidateFinder > argFinders =
1556 funcFinder.findSubExprs( clause.target.args );
1557
1558 // List all combinations of arguments
1559 std::vector< CandidateList > possibilities;
1560 combos( argFinders.begin(), argFinders.end(), back_inserter( possibilities ) );
1561
1562 // For every possible function:
1563 // * try matching the arguments to the parameters, not the other way around because
1564 // more arguments than parameters
1565 CandidateList funcCandidates;
1566 std::vector< CandidateList > argsCandidates;
1567 SemanticErrorException errors;
1568 for ( CandidateRef & func : funcFinder.candidates ) {
1569 try {
1570 auto pointerType = dynamic_cast< const ast::PointerType * >(
1571 func->expr->result->stripReferences() );
1572 if ( ! pointerType ) {
1573 SemanticError( stmt->location, func->expr->result.get(),
1574 "candidate not viable: not a pointer type\n" );
1575 }
1576
1577 auto funcType = pointerType->base.as< ast::FunctionType >();
1578 if ( ! funcType ) {
1579 SemanticError( stmt->location, func->expr->result.get(),
1580 "candidate not viable: not a function type\n" );
1581 }
1582
1583 {
1584 auto param = funcType->params.begin();
1585 auto paramEnd = funcType->params.end();
1586
1587 if( ! nextMutex( param, paramEnd ) ) {
1588 SemanticError( stmt->location, funcType,
1589 "candidate function not viable: no mutex parameters\n");
1590 }
1591 }
1592
1593 CandidateRef func2{ new Candidate{ *func } };
1594 // strip reference from function
1595 func2->expr = referenceToRvalueConversion( func->expr, func2->cost );
1596
1597 // Each argument must be matched with a parameter of the current candidate
1598 for ( auto & argsList : possibilities ) {
1599 try {
1600 // Declare data structures needed for resolution
1601 ast::OpenVarSet open;
1602 ast::AssertionSet need, have;
1603 ast::TypeEnvironment resultEnv{ func->env };
1604 // Add all type variables as open so that those not used in the
1605 // parameter list are still considered open
1606 resultEnv.add( funcType->forall );
1607
1608 // load type variables from arguments into one shared space
1609 for ( auto & arg : argsList ) {
1610 resultEnv.simpleCombine( arg->env );
1611 }
1612
1613 // Make sure we don't widen any existing bindings
1614 resultEnv.forbidWidening();
1615
1616 // Find any unbound type variables
1617 resultEnv.extractOpenVars( open );
1618
1619 auto param = funcType->params.begin();
1620 auto paramEnd = funcType->params.end();
1621
1622 unsigned n_mutex_param = 0;
1623
1624 // For every argument of its set, check if it matches one of the
1625 // parameters. The order is important
1626 for ( auto & arg : argsList ) {
1627 // Ignore non-mutex arguments
1628 if ( ! nextMutex( param, paramEnd ) ) {
1629 // We ran out of parameters but still have arguments.
1630 // This function doesn't match
1631 SemanticError( stmt->location, funcType,
1632 toString("candidate function not viable: too many mutex "
1633 "arguments, expected ", n_mutex_param, "\n" ) );
1634 }
1635
1636 ++n_mutex_param;
1637
1638 // Check if the argument matches the parameter type in the current
1639 // scope
1640 ast::ptr< ast::Type > paramType = (*param)->get_type();
1641 if (
1642 ! unify(
1643 arg->expr->result, paramType, resultEnv, need, have, open,
1644 symtab )
1645 ) {
1646 // Type doesn't match
1647 stringstream ss;
1648 ss << "candidate function not viable: no known conversion "
1649 "from '";
1650 ast::print( ss, (*param)->get_type() );
1651 ss << "' to '";
1652 ast::print( ss, arg->expr->result );
1653 ss << "' with env '";
1654 ast::print( ss, resultEnv );
1655 ss << "'\n";
1656 SemanticError( stmt->location, funcType, ss.str() );
1657 }
1658
1659 ++param;
1660 }
1661
1662 // All arguments match!
1663
1664 // Check if parameters are missing
1665 if ( nextMutex( param, paramEnd ) ) {
1666 do {
1667 ++n_mutex_param;
1668 ++param;
1669 } while ( nextMutex( param, paramEnd ) );
1670
1671 // We ran out of arguments but still have parameters left; this
1672 // function doesn't match
1673 SemanticError( stmt->location, funcType,
1674 toString( "candidate function not viable: too few mutex "
1675 "arguments, expected ", n_mutex_param, "\n" ) );
1676 }
1677
1678 // All parameters match!
1679
1680 // Finish the expressions to tie in proper environments
1681 finishExpr( func2->expr, resultEnv );
1682 for ( CandidateRef & arg : argsList ) {
1683 finishExpr( arg->expr, resultEnv );
1684 }
1685
1686 // This is a match, store it and save it for later
1687 funcCandidates.emplace_back( std::move( func2 ) );
1688 argsCandidates.emplace_back( std::move( argsList ) );
1689
1690 } catch ( SemanticErrorException & e ) {
1691 errors.append( e );
1692 }
1693 }
1694 } catch ( SemanticErrorException & e ) {
1695 errors.append( e );
1696 }
1697 }
1698
1699 // Make sure correct number of arguments
1700 if( funcCandidates.empty() ) {
1701 SemanticErrorException top( stmt->location,
1702 "No alternatives for function in call to waitfor" );
1703 top.append( errors );
1704 throw top;
1705 }
1706
1707 if( argsCandidates.empty() ) {
1708 SemanticErrorException top( stmt->location,
1709 "No alternatives for arguments in call to waitfor" );
1710 top.append( errors );
1711 throw top;
1712 }
1713
1714 if( funcCandidates.size() > 1 ) {
1715 SemanticErrorException top( stmt->location,
1716 "Ambiguous function in call to waitfor" );
1717 top.append( errors );
1718 throw top;
1719 }
1720 if( argsCandidates.size() > 1 ) {
1721 SemanticErrorException top( stmt->location,
1722 "Ambiguous arguments in call to waitfor" );
1723 top.append( errors );
1724 throw top;
1725 }
1726 // TODO: need to use findDeletedExpr to ensure no deleted identifiers are used.
1727
1728 // build new clause
1729 ast::WaitForStmt::Clause clause2;
1730
1731 clause2.target.func = funcCandidates.front()->expr;
1732
1733 clause2.target.args.reserve( clause.target.args.size() );
1734 for ( auto arg : argsCandidates.front() ) {
1735 clause2.target.args.emplace_back( std::move( arg->expr ) );
1736 }
1737
1738 // Resolve the conditions as if it were an IfStmt, statements normally
1739 clause2.cond = findSingleExpression( clause.cond, symtab );
1740 clause2.stmt = clause.stmt->accept( *visitor );
1741
1742 // set results into stmt
1743 auto n = mutate( stmt );
1744 n->clauses[i] = std::move( clause2 );
1745 stmt = n;
1746 }
1747
1748 if ( stmt->timeout.stmt ) {
1749 // resolve the timeout as a size_t, the conditions like IfStmt, and stmts normally
1750 ast::WaitForStmt::Timeout timeout2;
1751
1752 ast::ptr< ast::Type > target =
1753 new ast::BasicType{ ast::BasicType::LongLongUnsignedInt };
1754 timeout2.time = findSingleExpression( stmt->timeout.time, target, symtab );
1755 timeout2.cond = findSingleExpression( stmt->timeout.cond, symtab );
1756 timeout2.stmt = stmt->timeout.stmt->accept( *visitor );
1757
1758 // set results into stmt
1759 auto n = mutate( stmt );
1760 n->timeout = std::move( timeout2 );
1761 stmt = n;
1762 }
1763
1764 if ( stmt->orElse.stmt ) {
1765 // resolve the condition like IfStmt, stmts normally
1766 ast::WaitForStmt::OrElse orElse2;
1767
1768 orElse2.cond = findSingleExpression( stmt->orElse.cond, symtab );
1769 orElse2.stmt = stmt->orElse.stmt->accept( *visitor );
1770
1771 // set results into stmt
1772 auto n = mutate( stmt );
1773 n->orElse = std::move( orElse2 );
1774 stmt = n;
1775 }
1776
1777 return stmt;
1778 }
1779
1780
1781
1782 const ast::SingleInit * Resolver_new::previsit( const ast::SingleInit * singleInit ) {
1783 visit_children = false;
1784 // resolve initialization using the possibilities as determined by the `currentObject`
1785 // cursor.
1786 ast::ptr< ast::Expr > untyped = new ast::UntypedInitExpr{
1787 singleInit->location, singleInit->value, currentObject.getOptions() };
1788 ast::ptr<ast::Expr> newExpr = findSingleExpression( untyped, symtab );
1789 const ast::InitExpr * initExpr = newExpr.strict_as< ast::InitExpr >();
1790
1791 // move cursor to the object that is actually initialized
1792 currentObject.setNext( initExpr->designation );
1793
1794 // discard InitExpr wrapper and retain relevant pieces.
1795 // `initExpr` may have inferred params in the case where the expression specialized a
1796 // function pointer, and newExpr may already have inferParams of its own, so a simple
1797 // swap is not sufficient
1798 ast::Expr::InferUnion inferred = initExpr->inferred;
1799 swap_and_save_env( newExpr, initExpr->expr );
1800 newExpr.get_and_mutate()->inferred.splice( std::move(inferred) );
1801
1802 // get the actual object's type (may not exactly match what comes back from the resolver
1803 // due to conversions)
1804 const ast::Type * initContext = currentObject.getCurrentType();
1805
1806 removeExtraneousCast( newExpr, symtab );
1807
1808 // check if actual object's type is char[]
1809 if ( auto at = dynamic_cast< const ast::ArrayType * >( initContext ) ) {
1810 if ( isCharType( at->base ) ) {
1811 // check if the resolved type is char*
1812 if ( auto pt = newExpr->result.as< ast::PointerType >() ) {
1813 if ( isCharType( pt->base ) ) {
1814 // strip cast if we're initializing a char[] with a char*
1815 // e.g. char x[] = "hello"
1816 if ( auto ce = newExpr.as< ast::CastExpr >() ) {
1817 swap_and_save_env( newExpr, ce->arg );
1818 }
1819 }
1820 }
1821 }
1822 }
1823
1824 // move cursor to next object in preparation for next initializer
1825 currentObject.increment();
1826
1827 // set initializer expression to resolved expression
1828 return ast::mutate_field( singleInit, &ast::SingleInit::value, std::move(newExpr) );
1829 }
1830
1831 const ast::ListInit * Resolver_new::previsit( const ast::ListInit * listInit ) {
1832 // move cursor into brace-enclosed initializer-list
1833 currentObject.enterListInit( listInit->location );
1834
1835 assert( listInit->designations.size() == listInit->initializers.size() );
1836 for ( unsigned i = 0; i < listInit->designations.size(); ++i ) {
1837 // iterate designations and initializers in pairs, moving the cursor to the current
1838 // designated object and resolving the initializer against that object
1839 listInit = ast::mutate_field_index(
1840 listInit, &ast::ListInit::designations, i,
1841 currentObject.findNext( listInit->designations[i] ) );
1842 listInit = ast::mutate_field_index(
1843 listInit, &ast::ListInit::initializers, i,
1844 listInit->initializers[i]->accept( *visitor ) );
1845 }
1846
1847 // move cursor out of brace-enclosed initializer-list
1848 currentObject.exitListInit();
1849
1850 visit_children = false;
1851 return listInit;
1852 }
1853
1854 const ast::ConstructorInit * Resolver_new::previsit( const ast::ConstructorInit * ctorInit ) {
1855 visitor->maybe_accept( ctorInit, &ast::ConstructorInit::ctor );
1856 visitor->maybe_accept( ctorInit, &ast::ConstructorInit::dtor );
1857
1858 // found a constructor - can get rid of C-style initializer
1859 // xxx - Rob suggests this field is dead code
1860 ctorInit = ast::mutate_field( ctorInit, &ast::ConstructorInit::init, nullptr );
1861
1862 // intrinsic single-parameter constructors and destructors do nothing. Since this was
1863 // implicitly generated, there's no way for it to have side effects, so get rid of it to
1864 // clean up generated code
1865 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->ctor ) ) {
1866 ctorInit = ast::mutate_field( ctorInit, &ast::ConstructorInit::ctor, nullptr );
1867 }
1868 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->dtor ) ) {
1869 ctorInit = ast::mutate_field( ctorInit, &ast::ConstructorInit::dtor, nullptr );
1870 }
1871
1872 return ctorInit;
1873 }
1874
1875} // namespace ResolvExpr
1876
1877// Local Variables: //
1878// tab-width: 4 //
1879// mode: c++ //
1880// compile-command: "make install" //
1881// End: //
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