source: src/ResolvExpr/Resolver.cc@ da9a27c

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 da9a27c was b9fa85b, checked in by Andrew Beach <ajbeach@…>, 5 years ago

Should fix both trac #173 by porting the catch scoping hack to the new ast and the incompatability with older compiler intoduce in the read addition.

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File size: 67.9 KB
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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/utility.h" // for ValueGuard, group_iterate
41#include "InitTweak/GenInit.h"
42#include "InitTweak/InitTweak.h" // for isIntrinsicSingleArgCallStmt
43#include "ResolvExpr/TypeEnvironment.h" // for TypeEnvironment
44#include "SymTab/Autogen.h" // for SizeType
45#include "SymTab/Indexer.h" // for Indexer
46#include "SynTree/Declaration.h" // for ObjectDecl, TypeDecl, Declar...
47#include "SynTree/Expression.h" // for Expression, CastExpr, InitExpr
48#include "SynTree/Initializer.h" // for ConstructorInit, SingleInit
49#include "SynTree/Statement.h" // for ForStmt, Statement, BranchStmt
50#include "SynTree/Type.h" // for Type, BasicType, PointerType
51#include "SynTree/TypeSubstitution.h" // for TypeSubstitution
52#include "SynTree/Visitor.h" // for acceptAll, maybeAccept
53#include "Tuples/Tuples.h"
54#include "Validate/FindSpecialDecls.h" // for SizeType
55
56using namespace std;
57
58namespace ResolvExpr {
59 struct Resolver_old final : public WithIndexer, public WithGuards, public WithVisitorRef<Resolver_old>, public WithShortCircuiting, public WithStmtsToAdd {
60 Resolver_old() {}
61 Resolver_old( const SymTab::Indexer & other ) {
62 indexer = other;
63 }
64
65 void previsit( FunctionDecl * functionDecl );
66 void postvisit( FunctionDecl * functionDecl );
67 void previsit( ObjectDecl * objectDecll );
68 void previsit( EnumDecl * enumDecl );
69 void previsit( StaticAssertDecl * assertDecl );
70
71 void previsit( ArrayType * at );
72 void previsit( PointerType * at );
73
74 void previsit( ExprStmt * exprStmt );
75 void previsit( AsmExpr * asmExpr );
76 void previsit( AsmStmt * asmStmt );
77 void previsit( IfStmt * ifStmt );
78 void previsit( WhileStmt * whileStmt );
79 void previsit( ForStmt * forStmt );
80 void previsit( SwitchStmt * switchStmt );
81 void previsit( CaseStmt * caseStmt );
82 void previsit( BranchStmt * branchStmt );
83 void previsit( ReturnStmt * returnStmt );
84 void previsit( ThrowStmt * throwStmt );
85 void previsit( CatchStmt * catchStmt );
86 void postvisit( CatchStmt * catchStmt );
87 void previsit( WaitForStmt * stmt );
88
89 void previsit( SingleInit * singleInit );
90 void previsit( ListInit * listInit );
91 void previsit( ConstructorInit * ctorInit );
92 private:
93 typedef std::list< Initializer * >::iterator InitIterator;
94
95 template< typename PtrType >
96 void handlePtrType( PtrType * type );
97
98 void fallbackInit( ConstructorInit * ctorInit );
99
100 Type * functionReturn = nullptr;
101 CurrentObject currentObject = nullptr;
102 bool inEnumDecl = false;
103 };
104
105 struct ResolveWithExprs : public WithIndexer, public WithGuards, public WithVisitorRef<ResolveWithExprs>, public WithShortCircuiting, public WithStmtsToAdd {
106 void previsit( FunctionDecl * );
107 void previsit( WithStmt * );
108
109 void resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts );
110 };
111
112 void resolve( std::list< Declaration * > translationUnit ) {
113 PassVisitor<Resolver_old> resolver;
114 acceptAll( translationUnit, resolver );
115 }
116
117 void resolveDecl( Declaration * decl, const SymTab::Indexer & indexer ) {
118 PassVisitor<Resolver_old> resolver( indexer );
119 maybeAccept( decl, resolver );
120 }
121
122 namespace {
123 struct DeleteFinder_old : public WithShortCircuiting {
124 DeletedExpr * delExpr = nullptr;
125 void previsit( DeletedExpr * expr ) {
126 if ( delExpr ) visit_children = false;
127 else delExpr = expr;
128 }
129
130 void previsit( Expression * ) {
131 if ( delExpr ) visit_children = false;
132 }
133 };
134 }
135
136 DeletedExpr * findDeletedExpr( Expression * expr ) {
137 PassVisitor<DeleteFinder_old> finder;
138 expr->accept( finder );
139 return finder.pass.delExpr;
140 }
141
142 namespace {
143 struct StripCasts_old {
144 Expression * postmutate( CastExpr * castExpr ) {
145 if ( castExpr->isGenerated && ResolvExpr::typesCompatible( castExpr->arg->result, castExpr->result, SymTab::Indexer() ) ) {
146 // generated cast is to the same type as its argument, so it's unnecessary -- remove it
147 Expression * expr = castExpr->arg;
148 castExpr->arg = nullptr;
149 std::swap( expr->env, castExpr->env );
150 return expr;
151 }
152 return castExpr;
153 }
154
155 static void strip( Expression *& expr ) {
156 PassVisitor<StripCasts_old> stripper;
157 expr = expr->acceptMutator( stripper );
158 }
159 };
160
161 void finishExpr( Expression *& expr, const TypeEnvironment & env, TypeSubstitution * oldenv = nullptr ) {
162 expr->env = oldenv ? oldenv->clone() : new TypeSubstitution;
163 env.makeSubstitution( *expr->env );
164 StripCasts_old::strip( expr ); // remove unnecessary casts that may be buried in an expression
165 }
166
167 void removeExtraneousCast( Expression *& expr, const SymTab::Indexer & indexer ) {
168 if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( expr ) ) {
169 if ( typesCompatible( castExpr->arg->result, castExpr->result, indexer ) ) {
170 // cast is to the same type as its argument, so it's unnecessary -- remove it
171 expr = castExpr->arg;
172 castExpr->arg = nullptr;
173 std::swap( expr->env, castExpr->env );
174 delete castExpr;
175 }
176 }
177 }
178 } // namespace
179
180 namespace {
181 void findUnfinishedKindExpression(Expression * untyped, Alternative & alt, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, ResolvMode mode = ResolvMode{} ) {
182 assertf( untyped, "expected a non-null expression." );
183
184 // xxx - this isn't thread-safe, but should work until we parallelize the resolver
185 static unsigned recursion_level = 0;
186
187 ++recursion_level;
188 TypeEnvironment env;
189 AlternativeFinder finder( indexer, env );
190 finder.find( untyped, recursion_level == 1 ? mode.atTopLevel() : mode );
191 --recursion_level;
192
193 #if 0
194 if ( finder.get_alternatives().size() != 1 ) {
195 std::cerr << "untyped expr is ";
196 untyped->print( std::cerr );
197 std::cerr << std::endl << "alternatives are:";
198 for ( const Alternative & alt : finder.get_alternatives() ) {
199 alt.print( std::cerr );
200 } // for
201 } // if
202 #endif
203
204 // produce filtered list of alternatives
205 AltList candidates;
206 for ( Alternative & alt : finder.get_alternatives() ) {
207 if ( pred( alt ) ) {
208 candidates.push_back( std::move( alt ) );
209 }
210 }
211
212 // produce invalid error if no candidates
213 if ( candidates.empty() ) {
214 SemanticError( untyped, toString( "No reasonable alternatives for ", kindStr, (kindStr != "" ? " " : ""), "expression: ") );
215 }
216
217 // search for cheapest candidate
218 AltList winners;
219 bool seen_undeleted = false;
220 for ( unsigned i = 0; i < candidates.size(); ++i ) {
221 int c = winners.empty() ? -1 : candidates[i].cost.compare( winners.front().cost );
222
223 if ( c > 0 ) continue; // skip more expensive than winner
224
225 if ( c < 0 ) {
226 // reset on new cheapest
227 seen_undeleted = ! findDeletedExpr( candidates[i].expr );
228 winners.clear();
229 } else /* if ( c == 0 ) */ {
230 if ( findDeletedExpr( candidates[i].expr ) ) {
231 // skip deleted expression if already seen one equivalent-cost not
232 if ( seen_undeleted ) continue;
233 } else if ( ! seen_undeleted ) {
234 // replace list of equivalent-cost deleted expressions with one non-deleted
235 winners.clear();
236 seen_undeleted = true;
237 }
238 }
239
240 winners.emplace_back( std::move( candidates[i] ) );
241 }
242
243 // promote alternative.cvtCost to .cost
244 // xxx - I don't know why this is done, but I'm keeping the behaviour from findMinCost
245 for ( Alternative& winner : winners ) {
246 winner.cost = winner.cvtCost;
247 }
248
249 // produce ambiguous errors, if applicable
250 if ( winners.size() != 1 ) {
251 std::ostringstream stream;
252 stream << "Cannot choose between " << winners.size() << " alternatives for " << kindStr << (kindStr != "" ? " " : "") << "expression\n";
253 untyped->print( stream );
254 stream << " Alternatives are:\n";
255 printAlts( winners, stream, 1 );
256 SemanticError( untyped->location, stream.str() );
257 }
258
259 // single selected choice
260 Alternative& choice = winners.front();
261
262 // fail on only expression deleted
263 if ( ! seen_undeleted ) {
264 SemanticError( untyped->location, choice.expr, "Unique best alternative includes deleted identifier in " );
265 }
266
267 // xxx - check for ambiguous expressions
268
269 // output selected choice
270 alt = std::move( choice );
271 }
272
273 /// resolve `untyped` to the expression whose alternative satisfies `pred` with the lowest cost; kindStr is used for providing better error messages
274 void findKindExpression(Expression *& untyped, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, ResolvMode mode = ResolvMode{}) {
275 if ( ! untyped ) return;
276 Alternative choice;
277 findUnfinishedKindExpression( untyped, choice, indexer, kindStr, pred, mode );
278 finishExpr( choice.expr, choice.env, untyped->env );
279 delete untyped;
280 untyped = choice.expr;
281 choice.expr = nullptr;
282 }
283
284 bool standardAlternativeFilter( const Alternative & ) {
285 // currently don't need to filter, under normal circumstances.
286 // in the future, this may be useful for removing deleted expressions
287 return true;
288 }
289 } // namespace
290
291 // used in resolveTypeof
292 Expression * resolveInVoidContext( Expression * expr, const SymTab::Indexer & indexer ) {
293 TypeEnvironment env;
294 return resolveInVoidContext( expr, indexer, env );
295 }
296
297 Expression * resolveInVoidContext( Expression * expr, const SymTab::Indexer & indexer, TypeEnvironment & env ) {
298 // it's a property of the language that a cast expression has either 1 or 0 interpretations; if it has 0
299 // interpretations, an exception has already been thrown.
300 assertf( expr, "expected a non-null expression." );
301
302 CastExpr * untyped = new CastExpr( expr ); // cast to void
303 untyped->location = expr->location;
304
305 // set up and resolve expression cast to void
306 Alternative choice;
307 findUnfinishedKindExpression( untyped, choice, indexer, "", standardAlternativeFilter, ResolvMode::withAdjustment() );
308 CastExpr * castExpr = strict_dynamic_cast< CastExpr * >( choice.expr );
309 assert( castExpr );
310 env = std::move( choice.env );
311
312 // clean up resolved expression
313 Expression * ret = castExpr->arg;
314 castExpr->arg = nullptr;
315
316 // unlink the arg so that it isn't deleted twice at the end of the program
317 untyped->arg = nullptr;
318 return ret;
319 }
320
321 void findVoidExpression( Expression *& untyped, const SymTab::Indexer & indexer ) {
322 resetTyVarRenaming();
323 TypeEnvironment env;
324 Expression * newExpr = resolveInVoidContext( untyped, indexer, env );
325 finishExpr( newExpr, env, untyped->env );
326 delete untyped;
327 untyped = newExpr;
328 }
329
330 void findSingleExpression( Expression *& untyped, const SymTab::Indexer & indexer ) {
331 findKindExpression( untyped, indexer, "", standardAlternativeFilter );
332 }
333
334 void findSingleExpression( Expression *& untyped, Type * type, const SymTab::Indexer & indexer ) {
335 assert( untyped && type );
336 // transfer location to generated cast for error purposes
337 CodeLocation location = untyped->location;
338 untyped = new CastExpr( untyped, type );
339 untyped->location = location;
340 findSingleExpression( untyped, indexer );
341 removeExtraneousCast( untyped, indexer );
342 }
343
344 namespace {
345 bool isIntegralType( const Alternative & alt ) {
346 Type * type = alt.expr->result;
347 if ( dynamic_cast< EnumInstType * >( type ) ) {
348 return true;
349 } else if ( BasicType * bt = dynamic_cast< BasicType * >( type ) ) {
350 return bt->isInteger();
351 } else if ( dynamic_cast< ZeroType* >( type ) != nullptr || dynamic_cast< OneType* >( type ) != nullptr ) {
352 return true;
353 } else {
354 return false;
355 } // if
356 }
357
358 void findIntegralExpression( Expression *& untyped, const SymTab::Indexer & indexer ) {
359 findKindExpression( untyped, indexer, "condition", isIntegralType );
360 }
361 }
362
363
364 bool isStructOrUnion( const Alternative & alt ) {
365 Type * t = alt.expr->result->stripReferences();
366 return dynamic_cast< StructInstType * >( t ) || dynamic_cast< UnionInstType * >( t );
367 }
368
369 void resolveWithExprs( std::list< Declaration * > & translationUnit ) {
370 PassVisitor<ResolveWithExprs> resolver;
371 acceptAll( translationUnit, resolver );
372 }
373
374 void ResolveWithExprs::resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts ) {
375 for ( Expression *& expr : withExprs ) {
376 // only struct- and union-typed expressions are viable candidates
377 findKindExpression( expr, indexer, "with statement", isStructOrUnion );
378
379 // if with expression might be impure, create a temporary so that it is evaluated once
380 if ( Tuples::maybeImpure( expr ) ) {
381 static UniqueName tmpNamer( "_with_tmp_" );
382 ObjectDecl * tmp = ObjectDecl::newObject( tmpNamer.newName(), expr->result->clone(), new SingleInit( expr ) );
383 expr = new VariableExpr( tmp );
384 newStmts.push_back( new DeclStmt( tmp ) );
385 if ( InitTweak::isConstructable( tmp->type ) ) {
386 // generate ctor/dtor and resolve them
387 tmp->init = InitTweak::genCtorInit( tmp );
388 tmp->accept( *visitor );
389 }
390 }
391 }
392 }
393
394 void ResolveWithExprs::previsit( WithStmt * withStmt ) {
395 resolveWithExprs( withStmt->exprs, stmtsToAddBefore );
396 }
397
398 void ResolveWithExprs::previsit( FunctionDecl * functionDecl ) {
399 {
400 // resolve with-exprs with parameters in scope and add any newly generated declarations to the
401 // front of the function body.
402 auto guard = makeFuncGuard( [this]() { indexer.enterScope(); }, [this](){ indexer.leaveScope(); } );
403 indexer.addFunctionType( functionDecl->type );
404 std::list< Statement * > newStmts;
405 resolveWithExprs( functionDecl->withExprs, newStmts );
406 if ( functionDecl->statements ) {
407 functionDecl->statements->kids.splice( functionDecl->statements->kids.begin(), newStmts );
408 } else {
409 assertf( functionDecl->withExprs.empty() && newStmts.empty(), "Function %s without a body has with-clause and/or generated with declarations.", functionDecl->name.c_str() );
410 }
411 }
412 }
413
414 void Resolver_old::previsit( ObjectDecl * objectDecl ) {
415 // To handle initialization of routine pointers, e.g., int (*fp)(int) = foo(), means that
416 // class-variable initContext is changed multiple time because the LHS is analysed twice.
417 // The second analysis changes initContext because of a function type can contain object
418 // declarations in the return and parameter types. So each value of initContext is
419 // retained, so the type on the first analysis is preserved and used for selecting the RHS.
420 GuardValue( currentObject );
421 currentObject = CurrentObject( objectDecl->get_type() );
422 if ( inEnumDecl && dynamic_cast< EnumInstType * >( objectDecl->get_type() ) ) {
423 // enumerator initializers should not use the enum type to initialize, since
424 // the enum type is still incomplete at this point. Use signed int instead.
425 currentObject = CurrentObject( new BasicType( Type::Qualifiers(), BasicType::SignedInt ) );
426 }
427 }
428
429 template< typename PtrType >
430 void Resolver_old::handlePtrType( PtrType * type ) {
431 if ( type->get_dimension() ) {
432 findSingleExpression( type->dimension, Validate::SizeType->clone(), indexer );
433 }
434 }
435
436 void Resolver_old::previsit( ArrayType * at ) {
437 handlePtrType( at );
438 }
439
440 void Resolver_old::previsit( PointerType * pt ) {
441 handlePtrType( pt );
442 }
443
444 void Resolver_old::previsit( FunctionDecl * functionDecl ) {
445#if 0
446 std::cerr << "resolver visiting functiondecl ";
447 functionDecl->print( std::cerr );
448 std::cerr << std::endl;
449#endif
450 GuardValue( functionReturn );
451 functionReturn = ResolvExpr::extractResultType( functionDecl->type );
452 }
453
454 void Resolver_old::postvisit( FunctionDecl * functionDecl ) {
455 // default value expressions have an environment which shouldn't be there and trips up
456 // later passes.
457 // xxx - it might be necessary to somehow keep the information from this environment, but I
458 // can't currently see how it's useful.
459 for ( Declaration * d : functionDecl->type->parameters ) {
460 if ( ObjectDecl * obj = dynamic_cast< ObjectDecl * >( d ) ) {
461 if ( SingleInit * init = dynamic_cast< SingleInit * >( obj->init ) ) {
462 delete init->value->env;
463 init->value->env = nullptr;
464 }
465 }
466 }
467 }
468
469 void Resolver_old::previsit( EnumDecl * ) {
470 // in case we decide to allow nested enums
471 GuardValue( inEnumDecl );
472 inEnumDecl = true;
473 }
474
475 void Resolver_old::previsit( StaticAssertDecl * assertDecl ) {
476 findIntegralExpression( assertDecl->condition, indexer );
477 }
478
479 void Resolver_old::previsit( ExprStmt * exprStmt ) {
480 visit_children = false;
481 assertf( exprStmt->expr, "ExprStmt has null Expression in resolver" );
482 findVoidExpression( exprStmt->expr, indexer );
483 }
484
485 void Resolver_old::previsit( AsmExpr * asmExpr ) {
486 visit_children = false;
487 findVoidExpression( asmExpr->operand, indexer );
488 }
489
490 void Resolver_old::previsit( AsmStmt * asmStmt ) {
491 visit_children = false;
492 acceptAll( asmStmt->get_input(), *visitor );
493 acceptAll( asmStmt->get_output(), *visitor );
494 }
495
496 void Resolver_old::previsit( IfStmt * ifStmt ) {
497 findIntegralExpression( ifStmt->condition, indexer );
498 }
499
500 void Resolver_old::previsit( WhileStmt * whileStmt ) {
501 findIntegralExpression( whileStmt->condition, indexer );
502 }
503
504 void Resolver_old::previsit( ForStmt * forStmt ) {
505 if ( forStmt->condition ) {
506 findIntegralExpression( forStmt->condition, indexer );
507 } // if
508
509 if ( forStmt->increment ) {
510 findVoidExpression( forStmt->increment, indexer );
511 } // if
512 }
513
514 void Resolver_old::previsit( SwitchStmt * switchStmt ) {
515 GuardValue( currentObject );
516 findIntegralExpression( switchStmt->condition, indexer );
517
518 currentObject = CurrentObject( switchStmt->condition->result );
519 }
520
521 void Resolver_old::previsit( CaseStmt * caseStmt ) {
522 if ( caseStmt->condition ) {
523 std::list< InitAlternative > initAlts = currentObject.getOptions();
524 assertf( initAlts.size() == 1, "SwitchStmt did not correctly resolve an integral expression." );
525 // must remove cast from case statement because RangeExpr cannot be cast.
526 Expression * newExpr = new CastExpr( caseStmt->condition, initAlts.front().type->clone() );
527 findSingleExpression( newExpr, indexer );
528 // case condition cannot have a cast in C, so it must be removed, regardless of whether it performs a conversion.
529 // Ideally we would perform the conversion internally here.
530 if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( newExpr ) ) {
531 newExpr = castExpr->arg;
532 castExpr->arg = nullptr;
533 std::swap( newExpr->env, castExpr->env );
534 delete castExpr;
535 }
536 caseStmt->condition = newExpr;
537 }
538 }
539
540 void Resolver_old::previsit( BranchStmt * branchStmt ) {
541 visit_children = false;
542 // must resolve the argument for a computed goto
543 if ( branchStmt->get_type() == BranchStmt::Goto ) { // check for computed goto statement
544 if ( branchStmt->computedTarget ) {
545 // computed goto argument is void *
546 findSingleExpression( branchStmt->computedTarget, new PointerType( Type::Qualifiers(), new VoidType( Type::Qualifiers() ) ), indexer );
547 } // if
548 } // if
549 }
550
551 void Resolver_old::previsit( ReturnStmt * returnStmt ) {
552 visit_children = false;
553 if ( returnStmt->expr ) {
554 findSingleExpression( returnStmt->expr, functionReturn->clone(), indexer );
555 } // if
556 }
557
558 void Resolver_old::previsit( ThrowStmt * throwStmt ) {
559 visit_children = false;
560 // TODO: Replace *exception type with &exception type.
561 if ( throwStmt->get_expr() ) {
562 const StructDecl * exception_decl = indexer.lookupStruct( "__cfaehm_base_exception_t" );
563 assert( exception_decl );
564 Type * exceptType = new PointerType( noQualifiers, new StructInstType( noQualifiers, const_cast<StructDecl *>(exception_decl) ) );
565 findSingleExpression( throwStmt->expr, exceptType, indexer );
566 }
567 }
568
569 void Resolver_old::previsit( CatchStmt * catchStmt ) {
570 // Until we are very sure this invarent (ifs that move between passes have thenPart)
571 // holds, check it. This allows a check for when to decode the mangling.
572 if ( IfStmt * ifStmt = dynamic_cast<IfStmt *>( catchStmt->body ) ) {
573 assert( ifStmt->thenPart );
574 }
575 // Encode the catchStmt so the condition can see the declaration.
576 if ( catchStmt->cond ) {
577 IfStmt * ifStmt = new IfStmt( catchStmt->cond, nullptr, catchStmt->body );
578 catchStmt->cond = nullptr;
579 catchStmt->body = ifStmt;
580 }
581 }
582
583 void Resolver_old::postvisit( CatchStmt * catchStmt ) {
584 // Decode the catchStmt so everything is stored properly.
585 IfStmt * ifStmt = dynamic_cast<IfStmt *>( catchStmt->body );
586 if ( nullptr != ifStmt && nullptr == ifStmt->thenPart ) {
587 assert( ifStmt->condition );
588 assert( ifStmt->elsePart );
589 catchStmt->cond = ifStmt->condition;
590 catchStmt->body = ifStmt->elsePart;
591 ifStmt->condition = nullptr;
592 ifStmt->elsePart = nullptr;
593 delete ifStmt;
594 }
595 }
596
597 template< typename iterator_t >
598 inline bool advance_to_mutex( iterator_t & it, const iterator_t & end ) {
599 while( it != end && !(*it)->get_type()->get_mutex() ) {
600 it++;
601 }
602
603 return it != end;
604 }
605
606 void Resolver_old::previsit( WaitForStmt * stmt ) {
607 visit_children = false;
608
609 // Resolve all clauses first
610 for( auto& clause : stmt->clauses ) {
611
612 TypeEnvironment env;
613 AlternativeFinder funcFinder( indexer, env );
614
615 // Find all alternatives for a function in canonical form
616 funcFinder.findWithAdjustment( clause.target.function );
617
618 if ( funcFinder.get_alternatives().empty() ) {
619 stringstream ss;
620 ss << "Use of undeclared indentifier '";
621 ss << strict_dynamic_cast<NameExpr*>( clause.target.function )->name;
622 ss << "' in call to waitfor";
623 SemanticError( stmt->location, ss.str() );
624 }
625
626 if(clause.target.arguments.empty()) {
627 SemanticError( stmt->location, "Waitfor clause must have at least one mutex parameter");
628 }
629
630 // Find all alternatives for all arguments in canonical form
631 std::vector< AlternativeFinder > argAlternatives;
632 funcFinder.findSubExprs( clause.target.arguments.begin(), clause.target.arguments.end(), back_inserter( argAlternatives ) );
633
634 // List all combinations of arguments
635 std::vector< AltList > possibilities;
636 combos( argAlternatives.begin(), argAlternatives.end(), back_inserter( possibilities ) );
637
638 AltList func_candidates;
639 std::vector< AltList > args_candidates;
640
641 // For every possible function :
642 // try matching the arguments to the parameters
643 // not the other way around because we have more arguments than parameters
644 SemanticErrorException errors;
645 for ( Alternative & func : funcFinder.get_alternatives() ) {
646 try {
647 PointerType * pointer = dynamic_cast< PointerType* >( func.expr->get_result()->stripReferences() );
648 if( !pointer ) {
649 SemanticError( func.expr->get_result(), "candidate not viable: not a pointer type\n" );
650 }
651
652 FunctionType * function = dynamic_cast< FunctionType* >( pointer->get_base() );
653 if( !function ) {
654 SemanticError( pointer->get_base(), "candidate not viable: not a function type\n" );
655 }
656
657
658 {
659 auto param = function->parameters.begin();
660 auto param_end = function->parameters.end();
661
662 if( !advance_to_mutex( param, param_end ) ) {
663 SemanticError(function, "candidate function not viable: no mutex parameters\n");
664 }
665 }
666
667 Alternative newFunc( func );
668 // Strip reference from function
669 referenceToRvalueConversion( newFunc.expr, newFunc.cost );
670
671 // For all the set of arguments we have try to match it with the parameter of the current function alternative
672 for ( auto & argsList : possibilities ) {
673
674 try {
675 // Declare data structures need for resolution
676 OpenVarSet openVars;
677 AssertionSet resultNeed, resultHave;
678 TypeEnvironment resultEnv( func.env );
679 makeUnifiableVars( function, openVars, resultNeed );
680 // add all type variables as open variables now so that those not used in the parameter
681 // list are still considered open.
682 resultEnv.add( function->forall );
683
684 // Load type variables from arguemnts into one shared space
685 simpleCombineEnvironments( argsList.begin(), argsList.end(), resultEnv );
686
687 // Make sure we don't widen any existing bindings
688 resultEnv.forbidWidening();
689
690 // Find any unbound type variables
691 resultEnv.extractOpenVars( openVars );
692
693 auto param = function->parameters.begin();
694 auto param_end = function->parameters.end();
695
696 int n_mutex_param = 0;
697
698 // For every arguments of its set, check if it matches one of the parameter
699 // The order is important
700 for( auto & arg : argsList ) {
701
702 // Ignore non-mutex arguments
703 if( !advance_to_mutex( param, param_end ) ) {
704 // We ran out of parameters but still have arguments
705 // this function doesn't match
706 SemanticError( function, toString("candidate function not viable: too many mutex arguments, expected ", n_mutex_param, "\n" ));
707 }
708
709 n_mutex_param++;
710
711 // Check if the argument matches the parameter type in the current scope
712 if( ! unify( arg.expr->get_result(), (*param)->get_type(), resultEnv, resultNeed, resultHave, openVars, this->indexer ) ) {
713 // Type doesn't match
714 stringstream ss;
715 ss << "candidate function not viable: no known convertion from '";
716 (*param)->get_type()->print( ss );
717 ss << "' to '";
718 arg.expr->get_result()->print( ss );
719 ss << "' with env '";
720 resultEnv.print(ss);
721 ss << "'\n";
722 SemanticError( function, ss.str() );
723 }
724
725 param++;
726 }
727
728 // All arguments match !
729
730 // Check if parameters are missing
731 if( advance_to_mutex( param, param_end ) ) {
732 do {
733 n_mutex_param++;
734 param++;
735 } while( advance_to_mutex( param, param_end ) );
736
737 // We ran out of arguments but still have parameters left
738 // this function doesn't match
739 SemanticError( function, toString("candidate function not viable: too few mutex arguments, expected ", n_mutex_param, "\n" ));
740 }
741
742 // All parameters match !
743
744 // Finish the expressions to tie in the proper environments
745 finishExpr( newFunc.expr, resultEnv );
746 for( Alternative & alt : argsList ) {
747 finishExpr( alt.expr, resultEnv );
748 }
749
750 // This is a match store it and save it for later
751 func_candidates.push_back( newFunc );
752 args_candidates.push_back( argsList );
753
754 }
755 catch( SemanticErrorException & e ) {
756 errors.append( e );
757 }
758 }
759 }
760 catch( SemanticErrorException & e ) {
761 errors.append( e );
762 }
763 }
764
765 // Make sure we got the right number of arguments
766 if( func_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for function in call to waitfor" ); top.append( errors ); throw top; }
767 if( args_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for arguments in call to waitfor" ); top.append( errors ); throw top; }
768 if( func_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous function in call to waitfor" ); top.append( errors ); throw top; }
769 if( args_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous arguments in call to waitfor" ); top.append( errors ); throw top; }
770 // TODO: need to use findDeletedExpr to ensure no deleted identifiers are used.
771
772 // Swap the results from the alternative with the unresolved values.
773 // Alternatives will handle deletion on destruction
774 std::swap( clause.target.function, func_candidates.front().expr );
775 for( auto arg_pair : group_iterate( clause.target.arguments, args_candidates.front() ) ) {
776 std::swap ( std::get<0>( arg_pair), std::get<1>( arg_pair).expr );
777 }
778
779 // Resolve the conditions as if it were an IfStmt
780 // Resolve the statments normally
781 findSingleExpression( clause.condition, this->indexer );
782 clause.statement->accept( *visitor );
783 }
784
785
786 if( stmt->timeout.statement ) {
787 // Resolve the timeout as an size_t for now
788 // Resolve the conditions as if it were an IfStmt
789 // Resolve the statments normally
790 findSingleExpression( stmt->timeout.time, new BasicType( noQualifiers, BasicType::LongLongUnsignedInt ), this->indexer );
791 findSingleExpression( stmt->timeout.condition, this->indexer );
792 stmt->timeout.statement->accept( *visitor );
793 }
794
795 if( stmt->orelse.statement ) {
796 // Resolve the conditions as if it were an IfStmt
797 // Resolve the statments normally
798 findSingleExpression( stmt->orelse.condition, this->indexer );
799 stmt->orelse.statement->accept( *visitor );
800 }
801 }
802
803 bool isCharType( Type * t ) {
804 if ( BasicType * bt = dynamic_cast< BasicType * >( t ) ) {
805 return bt->get_kind() == BasicType::Char || bt->get_kind() == BasicType::SignedChar ||
806 bt->get_kind() == BasicType::UnsignedChar;
807 }
808 return false;
809 }
810
811 void Resolver_old::previsit( SingleInit * singleInit ) {
812 visit_children = false;
813 // resolve initialization using the possibilities as determined by the currentObject cursor
814 Expression * newExpr = new UntypedInitExpr( singleInit->value, currentObject.getOptions() );
815 findSingleExpression( newExpr, indexer );
816 InitExpr * initExpr = strict_dynamic_cast< InitExpr * >( newExpr );
817
818 // move cursor to the object that is actually initialized
819 currentObject.setNext( initExpr->get_designation() );
820
821 // discard InitExpr wrapper and retain relevant pieces
822 newExpr = initExpr->expr;
823 initExpr->expr = nullptr;
824 std::swap( initExpr->env, newExpr->env );
825 // InitExpr may have inferParams in the case where the expression specializes a function
826 // pointer, and newExpr may already have inferParams of its own, so a simple swap is not
827 // sufficient.
828 newExpr->spliceInferParams( initExpr );
829 delete initExpr;
830
831 // get the actual object's type (may not exactly match what comes back from the resolver
832 // due to conversions)
833 Type * initContext = currentObject.getCurrentType();
834
835 removeExtraneousCast( newExpr, indexer );
836
837 // check if actual object's type is char[]
838 if ( ArrayType * at = dynamic_cast< ArrayType * >( initContext ) ) {
839 if ( isCharType( at->get_base() ) ) {
840 // check if the resolved type is char *
841 if ( PointerType * pt = dynamic_cast< PointerType *>( newExpr->get_result() ) ) {
842 if ( isCharType( pt->get_base() ) ) {
843 if ( CastExpr * ce = dynamic_cast< CastExpr * >( newExpr ) ) {
844 // strip cast if we're initializing a char[] with a char *,
845 // e.g. char x[] = "hello";
846 newExpr = ce->get_arg();
847 ce->set_arg( nullptr );
848 std::swap( ce->env, newExpr->env );
849 delete ce;
850 }
851 }
852 }
853 }
854 }
855
856 // set initializer expr to resolved express
857 singleInit->value = newExpr;
858
859 // move cursor to next object in preparation for next initializer
860 currentObject.increment();
861 }
862
863 void Resolver_old::previsit( ListInit * listInit ) {
864 visit_children = false;
865 // move cursor into brace-enclosed initializer-list
866 currentObject.enterListInit();
867 // xxx - fix this so that the list isn't copied, iterator should be used to change current
868 // element
869 std::list<Designation *> newDesignations;
870 for ( auto p : group_iterate(listInit->get_designations(), listInit->get_initializers()) ) {
871 // iterate designations and initializers in pairs, moving the cursor to the current
872 // designated object and resolving the initializer against that object.
873 Designation * des = std::get<0>(p);
874 Initializer * init = std::get<1>(p);
875 newDesignations.push_back( currentObject.findNext( des ) );
876 init->accept( *visitor );
877 }
878 // set the set of 'resolved' designations and leave the brace-enclosed initializer-list
879 listInit->get_designations() = newDesignations; // xxx - memory management
880 currentObject.exitListInit();
881
882 // xxx - this part has not be folded into CurrentObject yet
883 // } else if ( TypeInstType * tt = dynamic_cast< TypeInstType * >( initContext ) ) {
884 // Type * base = tt->get_baseType()->get_base();
885 // if ( base ) {
886 // // know the implementation type, so try using that as the initContext
887 // ObjectDecl tmpObj( "", Type::StorageClasses(), LinkageSpec::Cforall, nullptr, base->clone(), nullptr );
888 // currentObject = &tmpObj;
889 // visit( listInit );
890 // } else {
891 // // missing implementation type -- might be an unknown type variable, so try proceeding with the current init context
892 // Parent::visit( listInit );
893 // }
894 // } else {
895 }
896
897 // ConstructorInit - fall back on C-style initializer
898 void Resolver_old::fallbackInit( ConstructorInit * ctorInit ) {
899 // could not find valid constructor, or found an intrinsic constructor
900 // fall back on C-style initializer
901 delete ctorInit->get_ctor();
902 ctorInit->set_ctor( nullptr );
903 delete ctorInit->get_dtor();
904 ctorInit->set_dtor( nullptr );
905 maybeAccept( ctorInit->get_init(), *visitor );
906 }
907
908 // needs to be callable from outside the resolver, so this is a standalone function
909 void resolveCtorInit( ConstructorInit * ctorInit, const SymTab::Indexer & indexer ) {
910 assert( ctorInit );
911 PassVisitor<Resolver_old> resolver( indexer );
912 ctorInit->accept( resolver );
913 }
914
915 void resolveStmtExpr( StmtExpr * stmtExpr, const SymTab::Indexer & indexer ) {
916 assert( stmtExpr );
917 PassVisitor<Resolver_old> resolver( indexer );
918 stmtExpr->accept( resolver );
919 stmtExpr->computeResult();
920 // xxx - aggregate the environments from all statements? Possibly in AlternativeFinder instead?
921 }
922
923 void Resolver_old::previsit( ConstructorInit * ctorInit ) {
924 visit_children = false;
925 // xxx - fallback init has been removed => remove fallbackInit function and remove complexity from FixInit and remove C-init from ConstructorInit
926 maybeAccept( ctorInit->ctor, *visitor );
927 maybeAccept( ctorInit->dtor, *visitor );
928
929 // found a constructor - can get rid of C-style initializer
930 delete ctorInit->init;
931 ctorInit->init = nullptr;
932
933 // intrinsic single parameter constructors and destructors do nothing. Since this was
934 // implicitly generated, there's no way for it to have side effects, so get rid of it
935 // to clean up generated code.
936 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->ctor ) ) {
937 delete ctorInit->ctor;
938 ctorInit->ctor = nullptr;
939 }
940
941 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->dtor ) ) {
942 delete ctorInit->dtor;
943 ctorInit->dtor = nullptr;
944 }
945
946 // xxx - todo -- what about arrays?
947 // if ( dtor == nullptr && InitTweak::isIntrinsicCallStmt( ctorInit->get_ctor() ) ) {
948 // // can reduce the constructor down to a SingleInit using the
949 // // second argument from the ctor call, since
950 // delete ctorInit->get_ctor();
951 // ctorInit->set_ctor( nullptr );
952
953 // Expression * arg =
954 // ctorInit->set_init( new SingleInit( arg ) );
955 // }
956 }
957
958 ///////////////////////////////////////////////////////////////////////////
959 //
960 // *** NEW RESOLVER ***
961 //
962 ///////////////////////////////////////////////////////////////////////////
963
964 namespace {
965 /// Finds deleted expressions in an expression tree
966 struct DeleteFinder_new final : public ast::WithShortCircuiting {
967 const ast::DeletedExpr * result = nullptr;
968
969 void previsit( const ast::DeletedExpr * expr ) {
970 if ( result ) { visit_children = false; }
971 else { result = expr; }
972 }
973
974 void previsit( const ast::Expr * ) {
975 if ( result ) { visit_children = false; }
976 }
977 };
978 } // anonymous namespace
979
980 /// Check if this expression is or includes a deleted expression
981 const ast::DeletedExpr * findDeletedExpr( const ast::Expr * expr ) {
982 return ast::Pass<DeleteFinder_new>::read( expr );
983 }
984
985 namespace {
986 /// always-accept candidate filter
987 bool anyCandidate( const Candidate & ) { return true; }
988
989 /// Calls the CandidateFinder and finds the single best candidate
990 CandidateRef findUnfinishedKindExpression(
991 const ast::Expr * untyped, const ast::SymbolTable & symtab, const std::string & kind,
992 std::function<bool(const Candidate &)> pred = anyCandidate, ResolvMode mode = {}
993 ) {
994 if ( ! untyped ) return nullptr;
995
996 // xxx - this isn't thread-safe, but should work until we parallelize the resolver
997 static unsigned recursion_level = 0;
998
999 ++recursion_level;
1000 ast::TypeEnvironment env;
1001 CandidateFinder finder{ symtab, env };
1002 finder.find( untyped, recursion_level == 1 ? mode.atTopLevel() : mode );
1003 --recursion_level;
1004
1005 // produce a filtered list of candidates
1006 CandidateList candidates;
1007 for ( auto & cand : finder.candidates ) {
1008 if ( pred( *cand ) ) { candidates.emplace_back( cand ); }
1009 }
1010
1011 // produce invalid error if no candidates
1012 if ( candidates.empty() ) {
1013 SemanticError( untyped,
1014 toString( "No reasonable alternatives for ", kind, (kind != "" ? " " : ""),
1015 "expression: ") );
1016 }
1017
1018 // search for cheapest candidate
1019 CandidateList winners;
1020 bool seen_undeleted = false;
1021 for ( CandidateRef & cand : candidates ) {
1022 int c = winners.empty() ? -1 : cand->cost.compare( winners.front()->cost );
1023
1024 if ( c > 0 ) continue; // skip more expensive than winner
1025
1026 if ( c < 0 ) {
1027 // reset on new cheapest
1028 seen_undeleted = ! findDeletedExpr( cand->expr );
1029 winners.clear();
1030 } else /* if ( c == 0 ) */ {
1031 if ( findDeletedExpr( cand->expr ) ) {
1032 // skip deleted expression if already seen one equivalent-cost not
1033 if ( seen_undeleted ) continue;
1034 } else if ( ! seen_undeleted ) {
1035 // replace list of equivalent-cost deleted expressions with one non-deleted
1036 winners.clear();
1037 seen_undeleted = true;
1038 }
1039 }
1040
1041 winners.emplace_back( std::move( cand ) );
1042 }
1043
1044 // promote candidate.cvtCost to .cost
1045 promoteCvtCost( winners );
1046
1047 // produce ambiguous errors, if applicable
1048 if ( winners.size() != 1 ) {
1049 std::ostringstream stream;
1050 stream << "Cannot choose between " << winners.size() << " alternatives for "
1051 << kind << (kind != "" ? " " : "") << "expression\n";
1052 ast::print( stream, untyped );
1053 stream << " Alternatives are:\n";
1054 print( stream, winners, 1 );
1055 SemanticError( untyped->location, stream.str() );
1056 }
1057
1058 // single selected choice
1059 CandidateRef & choice = winners.front();
1060
1061 // fail on only expression deleted
1062 if ( ! seen_undeleted ) {
1063 SemanticError( untyped->location, choice->expr.get(), "Unique best alternative "
1064 "includes deleted identifier in " );
1065 }
1066
1067 return std::move( choice );
1068 }
1069
1070 /// Strips extraneous casts out of an expression
1071 struct StripCasts_new final {
1072 const ast::Expr * postvisit( const ast::CastExpr * castExpr ) {
1073 if (
1074 castExpr->isGenerated == ast::GeneratedCast
1075 && typesCompatible( castExpr->arg->result, castExpr->result )
1076 ) {
1077 // generated cast is the same type as its argument, remove it after keeping env
1078 return ast::mutate_field(
1079 castExpr->arg.get(), &ast::Expr::env, castExpr->env );
1080 }
1081 return castExpr;
1082 }
1083
1084 static void strip( ast::ptr< ast::Expr > & expr ) {
1085 ast::Pass< StripCasts_new > stripper;
1086 expr = expr->accept( stripper );
1087 }
1088 };
1089
1090 /// Swaps argument into expression pointer, saving original environment
1091 void swap_and_save_env( ast::ptr< ast::Expr > & expr, const ast::Expr * newExpr ) {
1092 ast::ptr< ast::TypeSubstitution > env = expr->env;
1093 expr.set_and_mutate( newExpr )->env = env;
1094 }
1095
1096 /// Removes cast to type of argument (unlike StripCasts, also handles non-generated casts)
1097 void removeExtraneousCast( ast::ptr<ast::Expr> & expr, const ast::SymbolTable & symtab ) {
1098 if ( const ast::CastExpr * castExpr = expr.as< ast::CastExpr >() ) {
1099 if ( typesCompatible( castExpr->arg->result, castExpr->result, symtab ) ) {
1100 // cast is to the same type as its argument, remove it
1101 swap_and_save_env( expr, castExpr->arg );
1102 }
1103 }
1104 }
1105
1106 /// Establish post-resolver invariants for expressions
1107 void finishExpr(
1108 ast::ptr< ast::Expr > & expr, const ast::TypeEnvironment & env,
1109 const ast::TypeSubstitution * oldenv = nullptr
1110 ) {
1111 // set up new type substitution for expression
1112 ast::ptr< ast::TypeSubstitution > newenv =
1113 oldenv ? oldenv : new ast::TypeSubstitution{};
1114 env.writeToSubstitution( *newenv.get_and_mutate() );
1115 expr.get_and_mutate()->env = std::move( newenv );
1116 // remove unncecessary casts
1117 StripCasts_new::strip( expr );
1118 }
1119 } // anonymous namespace
1120
1121
1122 ast::ptr< ast::Expr > resolveInVoidContext(
1123 const ast::Expr * expr, const ast::SymbolTable & symtab, ast::TypeEnvironment & env
1124 ) {
1125 assertf( expr, "expected a non-null expression" );
1126
1127 // set up and resolve expression cast to void
1128 ast::ptr< ast::CastExpr > untyped = new ast::CastExpr{ expr };
1129 CandidateRef choice = findUnfinishedKindExpression(
1130 untyped, symtab, "", anyCandidate, ResolvMode::withAdjustment() );
1131
1132 // a cast expression has either 0 or 1 interpretations (by language rules);
1133 // if 0, an exception has already been thrown, and this code will not run
1134 const ast::CastExpr * castExpr = choice->expr.strict_as< ast::CastExpr >();
1135 env = std::move( choice->env );
1136
1137 return castExpr->arg;
1138 }
1139
1140 namespace {
1141 /// Resolve `untyped` to the expression whose candidate is the best match for a `void`
1142 /// context.
1143 ast::ptr< ast::Expr > findVoidExpression(
1144 const ast::Expr * untyped, const ast::SymbolTable & symtab
1145 ) {
1146 resetTyVarRenaming();
1147 ast::TypeEnvironment env;
1148 ast::ptr< ast::Expr > newExpr = resolveInVoidContext( untyped, symtab, env );
1149 finishExpr( newExpr, env, untyped->env );
1150 return newExpr;
1151 }
1152
1153 /// resolve `untyped` to the expression whose candidate satisfies `pred` with the
1154 /// lowest cost, returning the resolved version
1155 ast::ptr< ast::Expr > findKindExpression(
1156 const ast::Expr * untyped, const ast::SymbolTable & symtab,
1157 std::function<bool(const Candidate &)> pred = anyCandidate,
1158 const std::string & kind = "", ResolvMode mode = {}
1159 ) {
1160 if ( ! untyped ) return {};
1161 CandidateRef choice =
1162 findUnfinishedKindExpression( untyped, symtab, kind, pred, mode );
1163 finishExpr( choice->expr, choice->env, untyped->env );
1164 return std::move( choice->expr );
1165 }
1166
1167 /// Resolve `untyped` to the single expression whose candidate is the best match
1168 ast::ptr< ast::Expr > findSingleExpression(
1169 const ast::Expr * untyped, const ast::SymbolTable & symtab
1170 ) {
1171 return findKindExpression( untyped, symtab );
1172 }
1173 } // anonymous namespace
1174
1175 ast::ptr< ast::Expr > findSingleExpression(
1176 const ast::Expr * untyped, const ast::Type * type, const ast::SymbolTable & symtab
1177 ) {
1178 assert( untyped && type );
1179 ast::ptr< ast::Expr > castExpr = new ast::CastExpr{ untyped, type };
1180 ast::ptr< ast::Expr > newExpr = findSingleExpression( castExpr, symtab );
1181 removeExtraneousCast( newExpr, symtab );
1182 return newExpr;
1183 }
1184
1185 namespace {
1186 /// Predicate for "Candidate has integral type"
1187 bool hasIntegralType( const Candidate & i ) {
1188 const ast::Type * type = i.expr->result;
1189
1190 if ( auto bt = dynamic_cast< const ast::BasicType * >( type ) ) {
1191 return bt->isInteger();
1192 } else if (
1193 dynamic_cast< const ast::EnumInstType * >( type )
1194 || dynamic_cast< const ast::ZeroType * >( type )
1195 || dynamic_cast< const ast::OneType * >( type )
1196 ) {
1197 return true;
1198 } else return false;
1199 }
1200
1201 /// Resolve `untyped` as an integral expression, returning the resolved version
1202 ast::ptr< ast::Expr > findIntegralExpression(
1203 const ast::Expr * untyped, const ast::SymbolTable & symtab
1204 ) {
1205 return findKindExpression( untyped, symtab, hasIntegralType, "condition" );
1206 }
1207
1208 /// check if a type is a character type
1209 bool isCharType( const ast::Type * t ) {
1210 if ( auto bt = dynamic_cast< const ast::BasicType * >( t ) ) {
1211 return bt->kind == ast::BasicType::Char
1212 || bt->kind == ast::BasicType::SignedChar
1213 || bt->kind == ast::BasicType::UnsignedChar;
1214 }
1215 return false;
1216 }
1217
1218 /// Advance a type itertor to the next mutex parameter
1219 template<typename Iter>
1220 inline bool nextMutex( Iter & it, const Iter & end ) {
1221 while ( it != end && ! (*it)->get_type()->is_mutex() ) { ++it; }
1222 return it != end;
1223 }
1224 }
1225
1226 class Resolver_new final
1227 : public ast::WithSymbolTable, public ast::WithGuards,
1228 public ast::WithVisitorRef<Resolver_new>, public ast::WithShortCircuiting,
1229 public ast::WithStmtsToAdd<> {
1230
1231 ast::ptr< ast::Type > functionReturn = nullptr;
1232 ast::CurrentObject currentObject;
1233 bool inEnumDecl = false;
1234
1235 public:
1236 static size_t traceId;
1237 Resolver_new() = default;
1238 Resolver_new( const ast::SymbolTable & syms ) { symtab = syms; }
1239
1240 void previsit( const ast::FunctionDecl * );
1241 const ast::FunctionDecl * postvisit( const ast::FunctionDecl * );
1242 void previsit( const ast::ObjectDecl * );
1243 void previsit( const ast::EnumDecl * );
1244 const ast::StaticAssertDecl * previsit( const ast::StaticAssertDecl * );
1245
1246 const ast::ArrayType * previsit( const ast::ArrayType * );
1247 const ast::PointerType * previsit( const ast::PointerType * );
1248
1249 const ast::ExprStmt * previsit( const ast::ExprStmt * );
1250 const ast::AsmExpr * previsit( const ast::AsmExpr * );
1251 const ast::AsmStmt * previsit( const ast::AsmStmt * );
1252 const ast::IfStmt * previsit( const ast::IfStmt * );
1253 const ast::WhileStmt * previsit( const ast::WhileStmt * );
1254 const ast::ForStmt * previsit( const ast::ForStmt * );
1255 const ast::SwitchStmt * previsit( const ast::SwitchStmt * );
1256 const ast::CaseStmt * previsit( const ast::CaseStmt * );
1257 const ast::BranchStmt * previsit( const ast::BranchStmt * );
1258 const ast::ReturnStmt * previsit( const ast::ReturnStmt * );
1259 const ast::ThrowStmt * previsit( const ast::ThrowStmt * );
1260 const ast::CatchStmt * previsit( const ast::CatchStmt * );
1261 const ast::CatchStmt * postvisit( const ast::CatchStmt * );
1262 const ast::WaitForStmt * previsit( const ast::WaitForStmt * );
1263
1264 const ast::SingleInit * previsit( const ast::SingleInit * );
1265 const ast::ListInit * previsit( const ast::ListInit * );
1266 const ast::ConstructorInit * previsit( const ast::ConstructorInit * );
1267 };
1268 // size_t Resolver_new::traceId = Stats::Heap::new_stacktrace_id("Resolver");
1269
1270 void resolve( std::list< ast::ptr< ast::Decl > >& translationUnit ) {
1271 ast::Pass< Resolver_new >::run( translationUnit );
1272 }
1273
1274 ast::ptr< ast::Init > resolveCtorInit(
1275 const ast::ConstructorInit * ctorInit, const ast::SymbolTable & symtab
1276 ) {
1277 assert( ctorInit );
1278 ast::Pass< Resolver_new > resolver{ symtab };
1279 return ctorInit->accept( resolver );
1280 }
1281
1282 ast::ptr< ast::Expr > resolveStmtExpr(
1283 const ast::StmtExpr * stmtExpr, const ast::SymbolTable & symtab
1284 ) {
1285 assert( stmtExpr );
1286 ast::Pass< Resolver_new > resolver{ symtab };
1287 ast::ptr< ast::Expr > ret = stmtExpr;
1288 ret = ret->accept( resolver );
1289 strict_dynamic_cast< ast::StmtExpr * >( ret.get_and_mutate() )->computeResult();
1290 return ret;
1291 }
1292
1293 void Resolver_new::previsit( const ast::FunctionDecl * functionDecl ) {
1294 GuardValue( functionReturn );
1295 functionReturn = extractResultType( functionDecl->type );
1296 }
1297
1298 const ast::FunctionDecl * Resolver_new::postvisit( const ast::FunctionDecl * functionDecl ) {
1299 // default value expressions have an environment which shouldn't be there and trips up
1300 // later passes.
1301 assert( functionDecl->unique() );
1302 ast::FunctionType * mutType = mutate( functionDecl->type.get() );
1303
1304 for ( unsigned i = 0 ; i < mutType->params.size() ; ++i ) {
1305 if ( const ast::ObjectDecl * obj = mutType->params[i].as< ast::ObjectDecl >() ) {
1306 if ( const ast::SingleInit * init = obj->init.as< ast::SingleInit >() ) {
1307 if ( init->value->env == nullptr ) continue;
1308 // clone initializer minus the initializer environment
1309 auto mutParam = mutate( mutType->params[i].strict_as< ast::ObjectDecl >() );
1310 auto mutInit = mutate( mutParam->init.strict_as< ast::SingleInit >() );
1311 auto mutValue = mutate( mutInit->value.get() );
1312
1313 mutValue->env = nullptr;
1314 mutInit->value = mutValue;
1315 mutParam->init = mutInit;
1316 mutType->params[i] = mutParam;
1317
1318 assert( ! mutType->params[i].strict_as< ast::ObjectDecl >()->init.strict_as< ast::SingleInit >()->value->env);
1319 }
1320 }
1321 }
1322 mutate_field(functionDecl, &ast::FunctionDecl::type, mutType);
1323 return functionDecl;
1324 }
1325
1326 void Resolver_new::previsit( const ast::ObjectDecl * objectDecl ) {
1327 // To handle initialization of routine pointers [e.g. int (*fp)(int) = foo()],
1328 // class-variable `initContext` is changed multiple times because the LHS is analyzed
1329 // twice. The second analysis changes `initContext` because a function type can contain
1330 // object declarations in the return and parameter types. Therefore each value of
1331 // `initContext` is retained so the type on the first analysis is preserved and used for
1332 // selecting the RHS.
1333 GuardValue( currentObject );
1334 currentObject = ast::CurrentObject{ objectDecl->location, objectDecl->get_type() };
1335 if ( inEnumDecl && dynamic_cast< const ast::EnumInstType * >( objectDecl->get_type() ) ) {
1336 // enumerator initializers should not use the enum type to initialize, since the
1337 // enum type is still incomplete at this point. Use `int` instead.
1338 currentObject = ast::CurrentObject{
1339 objectDecl->location, new ast::BasicType{ ast::BasicType::SignedInt } };
1340 }
1341 }
1342
1343 void Resolver_new::previsit( const ast::EnumDecl * ) {
1344 // in case we decide to allow nested enums
1345 GuardValue( inEnumDecl );
1346 inEnumDecl = true;
1347 }
1348
1349 const ast::StaticAssertDecl * Resolver_new::previsit(
1350 const ast::StaticAssertDecl * assertDecl
1351 ) {
1352 return ast::mutate_field(
1353 assertDecl, &ast::StaticAssertDecl::cond,
1354 findIntegralExpression( assertDecl->cond, symtab ) );
1355 }
1356
1357 template< typename PtrType >
1358 const PtrType * handlePtrType( const PtrType * type, const ast::SymbolTable & symtab ) {
1359 if ( type->dimension ) {
1360 #warning should use new equivalent to Validate::SizeType rather than sizeType here
1361 ast::ptr< ast::Type > sizeType = new ast::BasicType{ ast::BasicType::LongUnsignedInt };
1362 ast::mutate_field(
1363 type, &PtrType::dimension,
1364 findSingleExpression( type->dimension, sizeType, symtab ) );
1365 }
1366 return type;
1367 }
1368
1369 const ast::ArrayType * Resolver_new::previsit( const ast::ArrayType * at ) {
1370 return handlePtrType( at, symtab );
1371 }
1372
1373 const ast::PointerType * Resolver_new::previsit( const ast::PointerType * pt ) {
1374 return handlePtrType( pt, symtab );
1375 }
1376
1377 const ast::ExprStmt * Resolver_new::previsit( const ast::ExprStmt * exprStmt ) {
1378 visit_children = false;
1379 assertf( exprStmt->expr, "ExprStmt has null expression in resolver" );
1380
1381 return ast::mutate_field(
1382 exprStmt, &ast::ExprStmt::expr, findVoidExpression( exprStmt->expr, symtab ) );
1383 }
1384
1385 const ast::AsmExpr * Resolver_new::previsit( const ast::AsmExpr * asmExpr ) {
1386 visit_children = false;
1387
1388 asmExpr = ast::mutate_field(
1389 asmExpr, &ast::AsmExpr::operand, findVoidExpression( asmExpr->operand, symtab ) );
1390
1391 return asmExpr;
1392 }
1393
1394 const ast::AsmStmt * Resolver_new::previsit( const ast::AsmStmt * asmStmt ) {
1395 visitor->maybe_accept( asmStmt, &ast::AsmStmt::input );
1396 visitor->maybe_accept( asmStmt, &ast::AsmStmt::output );
1397 visit_children = false;
1398 return asmStmt;
1399 }
1400
1401 const ast::IfStmt * Resolver_new::previsit( const ast::IfStmt * ifStmt ) {
1402 return ast::mutate_field(
1403 ifStmt, &ast::IfStmt::cond, findIntegralExpression( ifStmt->cond, symtab ) );
1404 }
1405
1406 const ast::WhileStmt * Resolver_new::previsit( const ast::WhileStmt * whileStmt ) {
1407 return ast::mutate_field(
1408 whileStmt, &ast::WhileStmt::cond, findIntegralExpression( whileStmt->cond, symtab ) );
1409 }
1410
1411 const ast::ForStmt * Resolver_new::previsit( const ast::ForStmt * forStmt ) {
1412 if ( forStmt->cond ) {
1413 forStmt = ast::mutate_field(
1414 forStmt, &ast::ForStmt::cond, findIntegralExpression( forStmt->cond, symtab ) );
1415 }
1416
1417 if ( forStmt->inc ) {
1418 forStmt = ast::mutate_field(
1419 forStmt, &ast::ForStmt::inc, findVoidExpression( forStmt->inc, symtab ) );
1420 }
1421
1422 return forStmt;
1423 }
1424
1425 const ast::SwitchStmt * Resolver_new::previsit( const ast::SwitchStmt * switchStmt ) {
1426 GuardValue( currentObject );
1427 switchStmt = ast::mutate_field(
1428 switchStmt, &ast::SwitchStmt::cond,
1429 findIntegralExpression( switchStmt->cond, symtab ) );
1430 currentObject = ast::CurrentObject{ switchStmt->location, switchStmt->cond->result };
1431 return switchStmt;
1432 }
1433
1434 const ast::CaseStmt * Resolver_new::previsit( const ast::CaseStmt * caseStmt ) {
1435 if ( caseStmt->cond ) {
1436 std::deque< ast::InitAlternative > initAlts = currentObject.getOptions();
1437 assertf( initAlts.size() == 1, "SwitchStmt did not correctly resolve an integral "
1438 "expression." );
1439
1440 ast::ptr< ast::Expr > untyped =
1441 new ast::CastExpr{ caseStmt->location, caseStmt->cond, initAlts.front().type };
1442 ast::ptr< ast::Expr > newExpr = findSingleExpression( untyped, symtab );
1443
1444 // case condition cannot have a cast in C, so it must be removed here, regardless of
1445 // whether it would perform a conversion.
1446 if ( const ast::CastExpr * castExpr = newExpr.as< ast::CastExpr >() ) {
1447 swap_and_save_env( newExpr, castExpr->arg );
1448 }
1449
1450 caseStmt = ast::mutate_field( caseStmt, &ast::CaseStmt::cond, newExpr );
1451 }
1452 return caseStmt;
1453 }
1454
1455 const ast::BranchStmt * Resolver_new::previsit( const ast::BranchStmt * branchStmt ) {
1456 visit_children = false;
1457 // must resolve the argument of a computed goto
1458 if ( branchStmt->kind == ast::BranchStmt::Goto && branchStmt->computedTarget ) {
1459 // computed goto argument is void*
1460 ast::ptr< ast::Type > target = new ast::PointerType{ new ast::VoidType{} };
1461 branchStmt = ast::mutate_field(
1462 branchStmt, &ast::BranchStmt::computedTarget,
1463 findSingleExpression( branchStmt->computedTarget, target, symtab ) );
1464 }
1465 return branchStmt;
1466 }
1467
1468 const ast::ReturnStmt * Resolver_new::previsit( const ast::ReturnStmt * returnStmt ) {
1469 visit_children = false;
1470 if ( returnStmt->expr ) {
1471 returnStmt = ast::mutate_field(
1472 returnStmt, &ast::ReturnStmt::expr,
1473 findSingleExpression( returnStmt->expr, functionReturn, symtab ) );
1474 }
1475 return returnStmt;
1476 }
1477
1478 const ast::ThrowStmt * Resolver_new::previsit( const ast::ThrowStmt * throwStmt ) {
1479 visit_children = false;
1480 if ( throwStmt->expr ) {
1481 const ast::StructDecl * exceptionDecl =
1482 symtab.lookupStruct( "__cfaehm_base_exception_t" );
1483 assert( exceptionDecl );
1484 ast::ptr< ast::Type > exceptType =
1485 new ast::PointerType{ new ast::StructInstType{ exceptionDecl } };
1486 throwStmt = ast::mutate_field(
1487 throwStmt, &ast::ThrowStmt::expr,
1488 findSingleExpression( throwStmt->expr, exceptType, symtab ) );
1489 }
1490 return throwStmt;
1491 }
1492
1493 const ast::CatchStmt * Resolver_new::previsit( const ast::CatchStmt * catchStmt ) {
1494 // Until we are very sure this invarent (ifs that move between passes have thenPart)
1495 // holds, check it. This allows a check for when to decode the mangling.
1496 if ( auto ifStmt = catchStmt->body.as<ast::IfStmt>() ) {
1497 assert( ifStmt->thenPart );
1498 }
1499 // Encode the catchStmt so the condition can see the declaration.
1500 if ( catchStmt->cond ) {
1501 ast::CatchStmt * stmt = mutate( catchStmt );
1502 stmt->body = new ast::IfStmt( stmt->location, stmt->cond, nullptr, stmt->body );
1503 stmt->cond = nullptr;
1504 return stmt;
1505 }
1506 return catchStmt;
1507 }
1508
1509 const ast::CatchStmt * Resolver_new::postvisit( const ast::CatchStmt * catchStmt ) {
1510 // Decode the catchStmt so everything is stored properly.
1511 const ast::IfStmt * ifStmt = catchStmt->body.as<ast::IfStmt>();
1512 if ( nullptr != ifStmt && nullptr == ifStmt->thenPart ) {
1513 assert( ifStmt->cond );
1514 assert( ifStmt->elsePart );
1515 ast::CatchStmt * stmt = ast::mutate( catchStmt );
1516 stmt->cond = ifStmt->cond;
1517 stmt->body = ifStmt->elsePart;
1518 // ifStmt should be implicately deleted here.
1519 return stmt;
1520 }
1521 return catchStmt;
1522 }
1523
1524 const ast::WaitForStmt * Resolver_new::previsit( const ast::WaitForStmt * stmt ) {
1525 visit_children = false;
1526
1527 // Resolve all clauses first
1528 for ( unsigned i = 0; i < stmt->clauses.size(); ++i ) {
1529 const ast::WaitForStmt::Clause & clause = stmt->clauses[i];
1530
1531 ast::TypeEnvironment env;
1532 CandidateFinder funcFinder{ symtab, env };
1533
1534 // Find all candidates for a function in canonical form
1535 funcFinder.find( clause.target.func, ResolvMode::withAdjustment() );
1536
1537 if ( funcFinder.candidates.empty() ) {
1538 stringstream ss;
1539 ss << "Use of undeclared indentifier '";
1540 ss << clause.target.func.strict_as< ast::NameExpr >()->name;
1541 ss << "' in call to waitfor";
1542 SemanticError( stmt->location, ss.str() );
1543 }
1544
1545 if ( clause.target.args.empty() ) {
1546 SemanticError( stmt->location,
1547 "Waitfor clause must have at least one mutex parameter");
1548 }
1549
1550 // Find all alternatives for all arguments in canonical form
1551 std::vector< CandidateFinder > argFinders =
1552 funcFinder.findSubExprs( clause.target.args );
1553
1554 // List all combinations of arguments
1555 std::vector< CandidateList > possibilities;
1556 combos( argFinders.begin(), argFinders.end(), back_inserter( possibilities ) );
1557
1558 // For every possible function:
1559 // * try matching the arguments to the parameters, not the other way around because
1560 // more arguments than parameters
1561 CandidateList funcCandidates;
1562 std::vector< CandidateList > argsCandidates;
1563 SemanticErrorException errors;
1564 for ( CandidateRef & func : funcFinder.candidates ) {
1565 try {
1566 auto pointerType = dynamic_cast< const ast::PointerType * >(
1567 func->expr->result->stripReferences() );
1568 if ( ! pointerType ) {
1569 SemanticError( stmt->location, func->expr->result.get(),
1570 "candidate not viable: not a pointer type\n" );
1571 }
1572
1573 auto funcType = pointerType->base.as< ast::FunctionType >();
1574 if ( ! funcType ) {
1575 SemanticError( stmt->location, func->expr->result.get(),
1576 "candidate not viable: not a function type\n" );
1577 }
1578
1579 {
1580 auto param = funcType->params.begin();
1581 auto paramEnd = funcType->params.end();
1582
1583 if( ! nextMutex( param, paramEnd ) ) {
1584 SemanticError( stmt->location, funcType,
1585 "candidate function not viable: no mutex parameters\n");
1586 }
1587 }
1588
1589 CandidateRef func2{ new Candidate{ *func } };
1590 // strip reference from function
1591 func2->expr = referenceToRvalueConversion( func->expr, func2->cost );
1592
1593 // Each argument must be matched with a parameter of the current candidate
1594 for ( auto & argsList : possibilities ) {
1595 try {
1596 // Declare data structures needed for resolution
1597 ast::OpenVarSet open;
1598 ast::AssertionSet need, have;
1599 ast::TypeEnvironment resultEnv{ func->env };
1600 // Add all type variables as open so that those not used in the
1601 // parameter list are still considered open
1602 resultEnv.add( funcType->forall );
1603
1604 // load type variables from arguments into one shared space
1605 for ( auto & arg : argsList ) {
1606 resultEnv.simpleCombine( arg->env );
1607 }
1608
1609 // Make sure we don't widen any existing bindings
1610 resultEnv.forbidWidening();
1611
1612 // Find any unbound type variables
1613 resultEnv.extractOpenVars( open );
1614
1615 auto param = funcType->params.begin();
1616 auto paramEnd = funcType->params.end();
1617
1618 unsigned n_mutex_param = 0;
1619
1620 // For every argument of its set, check if it matches one of the
1621 // parameters. The order is important
1622 for ( auto & arg : argsList ) {
1623 // Ignore non-mutex arguments
1624 if ( ! nextMutex( param, paramEnd ) ) {
1625 // We ran out of parameters but still have arguments.
1626 // This function doesn't match
1627 SemanticError( stmt->location, funcType,
1628 toString("candidate function not viable: too many mutex "
1629 "arguments, expected ", n_mutex_param, "\n" ) );
1630 }
1631
1632 ++n_mutex_param;
1633
1634 // Check if the argument matches the parameter type in the current
1635 // scope
1636 ast::ptr< ast::Type > paramType = (*param)->get_type();
1637 if (
1638 ! unify(
1639 arg->expr->result, paramType, resultEnv, need, have, open,
1640 symtab )
1641 ) {
1642 // Type doesn't match
1643 stringstream ss;
1644 ss << "candidate function not viable: no known conversion "
1645 "from '";
1646 ast::print( ss, (*param)->get_type() );
1647 ss << "' to '";
1648 ast::print( ss, arg->expr->result );
1649 ss << "' with env '";
1650 ast::print( ss, resultEnv );
1651 ss << "'\n";
1652 SemanticError( stmt->location, funcType, ss.str() );
1653 }
1654
1655 ++param;
1656 }
1657
1658 // All arguments match!
1659
1660 // Check if parameters are missing
1661 if ( nextMutex( param, paramEnd ) ) {
1662 do {
1663 ++n_mutex_param;
1664 ++param;
1665 } while ( nextMutex( param, paramEnd ) );
1666
1667 // We ran out of arguments but still have parameters left; this
1668 // function doesn't match
1669 SemanticError( stmt->location, funcType,
1670 toString( "candidate function not viable: too few mutex "
1671 "arguments, expected ", n_mutex_param, "\n" ) );
1672 }
1673
1674 // All parameters match!
1675
1676 // Finish the expressions to tie in proper environments
1677 finishExpr( func2->expr, resultEnv );
1678 for ( CandidateRef & arg : argsList ) {
1679 finishExpr( arg->expr, resultEnv );
1680 }
1681
1682 // This is a match, store it and save it for later
1683 funcCandidates.emplace_back( std::move( func2 ) );
1684 argsCandidates.emplace_back( std::move( argsList ) );
1685
1686 } catch ( SemanticErrorException & e ) {
1687 errors.append( e );
1688 }
1689 }
1690 } catch ( SemanticErrorException & e ) {
1691 errors.append( e );
1692 }
1693 }
1694
1695 // Make sure correct number of arguments
1696 if( funcCandidates.empty() ) {
1697 SemanticErrorException top( stmt->location,
1698 "No alternatives for function in call to waitfor" );
1699 top.append( errors );
1700 throw top;
1701 }
1702
1703 if( argsCandidates.empty() ) {
1704 SemanticErrorException top( stmt->location,
1705 "No alternatives for arguments in call to waitfor" );
1706 top.append( errors );
1707 throw top;
1708 }
1709
1710 if( funcCandidates.size() > 1 ) {
1711 SemanticErrorException top( stmt->location,
1712 "Ambiguous function in call to waitfor" );
1713 top.append( errors );
1714 throw top;
1715 }
1716 if( argsCandidates.size() > 1 ) {
1717 SemanticErrorException top( stmt->location,
1718 "Ambiguous arguments in call to waitfor" );
1719 top.append( errors );
1720 throw top;
1721 }
1722 // TODO: need to use findDeletedExpr to ensure no deleted identifiers are used.
1723
1724 // build new clause
1725 ast::WaitForStmt::Clause clause2;
1726
1727 clause2.target.func = funcCandidates.front()->expr;
1728
1729 clause2.target.args.reserve( clause.target.args.size() );
1730 for ( auto arg : argsCandidates.front() ) {
1731 clause2.target.args.emplace_back( std::move( arg->expr ) );
1732 }
1733
1734 // Resolve the conditions as if it were an IfStmt, statements normally
1735 clause2.cond = findSingleExpression( clause.cond, symtab );
1736 clause2.stmt = clause.stmt->accept( *visitor );
1737
1738 // set results into stmt
1739 auto n = mutate( stmt );
1740 n->clauses[i] = std::move( clause2 );
1741 stmt = n;
1742 }
1743
1744 if ( stmt->timeout.stmt ) {
1745 // resolve the timeout as a size_t, the conditions like IfStmt, and stmts normally
1746 ast::WaitForStmt::Timeout timeout2;
1747
1748 ast::ptr< ast::Type > target =
1749 new ast::BasicType{ ast::BasicType::LongLongUnsignedInt };
1750 timeout2.time = findSingleExpression( stmt->timeout.time, target, symtab );
1751 timeout2.cond = findSingleExpression( stmt->timeout.cond, symtab );
1752 timeout2.stmt = stmt->timeout.stmt->accept( *visitor );
1753
1754 // set results into stmt
1755 auto n = mutate( stmt );
1756 n->timeout = std::move( timeout2 );
1757 stmt = n;
1758 }
1759
1760 if ( stmt->orElse.stmt ) {
1761 // resolve the condition like IfStmt, stmts normally
1762 ast::WaitForStmt::OrElse orElse2;
1763
1764 orElse2.cond = findSingleExpression( stmt->orElse.cond, symtab );
1765 orElse2.stmt = stmt->orElse.stmt->accept( *visitor );
1766
1767 // set results into stmt
1768 auto n = mutate( stmt );
1769 n->orElse = std::move( orElse2 );
1770 stmt = n;
1771 }
1772
1773 return stmt;
1774 }
1775
1776
1777
1778 const ast::SingleInit * Resolver_new::previsit( const ast::SingleInit * singleInit ) {
1779 visit_children = false;
1780 // resolve initialization using the possibilities as determined by the `currentObject`
1781 // cursor.
1782 ast::ptr< ast::Expr > untyped = new ast::UntypedInitExpr{
1783 singleInit->location, singleInit->value, currentObject.getOptions() };
1784 ast::ptr<ast::Expr> newExpr = findSingleExpression( untyped, symtab );
1785 const ast::InitExpr * initExpr = newExpr.strict_as< ast::InitExpr >();
1786
1787 // move cursor to the object that is actually initialized
1788 currentObject.setNext( initExpr->designation );
1789
1790 // discard InitExpr wrapper and retain relevant pieces.
1791 // `initExpr` may have inferred params in the case where the expression specialized a
1792 // function pointer, and newExpr may already have inferParams of its own, so a simple
1793 // swap is not sufficient
1794 ast::Expr::InferUnion inferred = initExpr->inferred;
1795 swap_and_save_env( newExpr, initExpr->expr );
1796 newExpr.get_and_mutate()->inferred.splice( std::move(inferred) );
1797
1798 // get the actual object's type (may not exactly match what comes back from the resolver
1799 // due to conversions)
1800 const ast::Type * initContext = currentObject.getCurrentType();
1801
1802 removeExtraneousCast( newExpr, symtab );
1803
1804 // check if actual object's type is char[]
1805 if ( auto at = dynamic_cast< const ast::ArrayType * >( initContext ) ) {
1806 if ( isCharType( at->base ) ) {
1807 // check if the resolved type is char*
1808 if ( auto pt = newExpr->result.as< ast::PointerType >() ) {
1809 if ( isCharType( pt->base ) ) {
1810 // strip cast if we're initializing a char[] with a char*
1811 // e.g. char x[] = "hello"
1812 if ( auto ce = newExpr.as< ast::CastExpr >() ) {
1813 swap_and_save_env( newExpr, ce->arg );
1814 }
1815 }
1816 }
1817 }
1818 }
1819
1820 // move cursor to next object in preparation for next initializer
1821 currentObject.increment();
1822
1823 // set initializer expression to resolved expression
1824 return ast::mutate_field( singleInit, &ast::SingleInit::value, std::move(newExpr) );
1825 }
1826
1827 const ast::ListInit * Resolver_new::previsit( const ast::ListInit * listInit ) {
1828 // move cursor into brace-enclosed initializer-list
1829 currentObject.enterListInit( listInit->location );
1830
1831 assert( listInit->designations.size() == listInit->initializers.size() );
1832 for ( unsigned i = 0; i < listInit->designations.size(); ++i ) {
1833 // iterate designations and initializers in pairs, moving the cursor to the current
1834 // designated object and resolving the initializer against that object
1835 listInit = ast::mutate_field_index(
1836 listInit, &ast::ListInit::designations, i,
1837 currentObject.findNext( listInit->designations[i] ) );
1838 listInit = ast::mutate_field_index(
1839 listInit, &ast::ListInit::initializers, i,
1840 listInit->initializers[i]->accept( *visitor ) );
1841 }
1842
1843 // move cursor out of brace-enclosed initializer-list
1844 currentObject.exitListInit();
1845
1846 visit_children = false;
1847 return listInit;
1848 }
1849
1850 const ast::ConstructorInit * Resolver_new::previsit( const ast::ConstructorInit * ctorInit ) {
1851 visitor->maybe_accept( ctorInit, &ast::ConstructorInit::ctor );
1852 visitor->maybe_accept( ctorInit, &ast::ConstructorInit::dtor );
1853
1854 // found a constructor - can get rid of C-style initializer
1855 // xxx - Rob suggests this field is dead code
1856 ctorInit = ast::mutate_field( ctorInit, &ast::ConstructorInit::init, nullptr );
1857
1858 // intrinsic single-parameter constructors and destructors do nothing. Since this was
1859 // implicitly generated, there's no way for it to have side effects, so get rid of it to
1860 // clean up generated code
1861 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->ctor ) ) {
1862 ctorInit = ast::mutate_field( ctorInit, &ast::ConstructorInit::ctor, nullptr );
1863 }
1864 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->dtor ) ) {
1865 ctorInit = ast::mutate_field( ctorInit, &ast::ConstructorInit::dtor, nullptr );
1866 }
1867
1868 return ctorInit;
1869 }
1870
1871} // namespace ResolvExpr
1872
1873// Local Variables: //
1874// tab-width: 4 //
1875// mode: c++ //
1876// compile-command: "make install" //
1877// End: //
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