source: src/ResolvExpr/Resolver.cc@ d22e90f

ADT aaron-thesis arm-eh ast-experimental cleanup-dtors deferred_resn demangler enum forall-pointer-decay jacob/cs343-translation jenkins-sandbox new-ast new-ast-unique-expr new-env no_list persistent-indexer pthread-emulation qualifiedEnum resolv-new with_gc
Last change on this file since d22e90f was a4ca48c, checked in by Rob Schluntz <rschlunt@…>, 8 years ago

Convert Resolver to PassVisitor
  • Property mode set to 100644
File size: 19.9 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 : Richard C. Bilson
10// Created On : Sun May 17 12:17:01 2015
11// Last Modified By : Andrew Beach
12// Last Modified On : Tus Aug 8 16:06:00 2017
13// Update Count : 212
14//
15
16#include <stddef.h> // for NULL
17#include <cassert> // for strict_dynamic_cast, assert
18#include <memory> // for allocator, allocator_traits<...
19#include <tuple> // for get
20
21#include "Alternative.h" // for Alternative, AltList
22#include "AlternativeFinder.h" // for AlternativeFinder, resolveIn...
23#include "Common/PassVisitor.h" // for PassVisitor
24#include "Common/SemanticError.h" // for SemanticError
25#include "Common/utility.h" // for ValueGuard, group_iterate
26#include "CurrentObject.h" // for CurrentObject
27#include "InitTweak/InitTweak.h" // for isIntrinsicSingleArgCallStmt
28#include "RenameVars.h" // for RenameVars, global_renamer
29#include "ResolvExpr/TypeEnvironment.h" // for TypeEnvironment
30#include "ResolveTypeof.h" // for resolveTypeof
31#include "Resolver.h"
32#include "SymTab/Autogen.h" // for SizeType
33#include "SymTab/Indexer.h" // for Indexer
34#include "SynTree/Declaration.h" // for ObjectDecl, TypeDecl, Declar...
35#include "SynTree/Expression.h" // for Expression, CastExpr, InitExpr
36#include "SynTree/Initializer.h" // for ConstructorInit, SingleInit
37#include "SynTree/Statement.h" // for ForStmt, Statement, BranchStmt
38#include "SynTree/Type.h" // for Type, BasicType, PointerType
39#include "SynTree/TypeSubstitution.h" // for TypeSubstitution
40#include "SynTree/Visitor.h" // for acceptAll, maybeAccept
41#include "typeops.h" // for extractResultType
42
43using namespace std;
44
45namespace ResolvExpr {
46 struct Resolver final : public WithIndexer, public WithGuards, public WithVisitorRef<Resolver>, public WithShortCircuiting {
47 Resolver() {}
48 Resolver( const SymTab::Indexer & other ) {
49 indexer = other;
50 }
51
52 void previsit( FunctionDecl *functionDecl );
53 void postvisit( FunctionDecl *functionDecl );
54 void previsit( ObjectDecl *functionDecl );
55 void previsit( TypeDecl *typeDecl );
56 void previsit( EnumDecl * enumDecl );
57
58 void previsit( ArrayType * at );
59 void previsit( PointerType * at );
60
61 void previsit( ExprStmt *exprStmt );
62 void previsit( AsmExpr *asmExpr );
63 void previsit( AsmStmt *asmStmt );
64 void previsit( IfStmt *ifStmt );
65 void previsit( WhileStmt *whileStmt );
66 void previsit( ForStmt *forStmt );
67 void previsit( SwitchStmt *switchStmt );
68 void previsit( CaseStmt *caseStmt );
69 void previsit( BranchStmt *branchStmt );
70 void previsit( ReturnStmt *returnStmt );
71 void previsit( ThrowStmt *throwStmt );
72 void previsit( CatchStmt *catchStmt );
73
74 void previsit( SingleInit *singleInit );
75 void previsit( ListInit *listInit );
76 void previsit( ConstructorInit *ctorInit );
77 private:
78 typedef std::list< Initializer * >::iterator InitIterator;
79
80 template< typename PtrType >
81 void handlePtrType( PtrType * type );
82
83 void resolveAggrInit( ReferenceToType *, InitIterator &, InitIterator & );
84 void resolveSingleAggrInit( Declaration *, InitIterator &, InitIterator &, TypeSubstitution sub );
85 void fallbackInit( ConstructorInit * ctorInit );
86
87 Type * functionReturn = nullptr;
88 CurrentObject currentObject = nullptr;
89 bool inEnumDecl = false;
90 };
91
92 void resolve( std::list< Declaration * > translationUnit ) {
93 PassVisitor<Resolver> resolver;
94 acceptAll( translationUnit, resolver );
95 }
96
97 // used in resolveTypeof
98 Expression *resolveInVoidContext( Expression *expr, const SymTab::Indexer &indexer ) {
99 TypeEnvironment env;
100 return resolveInVoidContext( expr, indexer, env );
101 }
102
103 namespace {
104 void finishExpr( Expression *expr, const TypeEnvironment &env ) {
105 expr->set_env( new TypeSubstitution );
106 env.makeSubstitution( *expr->get_env() );
107 }
108 } // namespace
109
110 Expression *findVoidExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
111 global_renamer.reset();
112 TypeEnvironment env;
113 Expression *newExpr = resolveInVoidContext( untyped, indexer, env );
114 finishExpr( newExpr, env );
115 return newExpr;
116 }
117
118 namespace {
119 Expression *findSingleExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
120 TypeEnvironment env;
121 AlternativeFinder finder( indexer, env );
122 finder.find( untyped );
123#if 0
124 if ( finder.get_alternatives().size() != 1 ) {
125 std::cout << "untyped expr is ";
126 untyped->print( std::cout );
127 std::cout << std::endl << "alternatives are:";
128 for ( std::list< Alternative >::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
129 i->print( std::cout );
130 } // for
131 } // if
132#endif
133 assertf( finder.get_alternatives().size() == 1, "findSingleExpression: must have exactly one alternative at the end." );
134 Alternative &choice = finder.get_alternatives().front();
135 Expression *newExpr = choice.expr->clone();
136 finishExpr( newExpr, choice.env );
137 return newExpr;
138 }
139
140 bool isIntegralType( Type *type ) {
141 if ( dynamic_cast< EnumInstType * >( type ) ) {
142 return true;
143 } else if ( BasicType *bt = dynamic_cast< BasicType * >( type ) ) {
144 return bt->isInteger();
145 } else if ( dynamic_cast< ZeroType* >( type ) != nullptr || dynamic_cast< OneType* >( type ) != nullptr ) {
146 return true;
147 } else {
148 return false;
149 } // if
150 }
151
152 Expression *findIntegralExpression( Expression *untyped, const SymTab::Indexer &indexer ) {
153 TypeEnvironment env;
154 AlternativeFinder finder( indexer, env );
155 finder.find( untyped );
156#if 0
157 if ( finder.get_alternatives().size() != 1 ) {
158 std::cout << "untyped expr is ";
159 untyped->print( std::cout );
160 std::cout << std::endl << "alternatives are:";
161 for ( std::list< Alternative >::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
162 i->print( std::cout );
163 } // for
164 } // if
165#endif
166 Expression *newExpr = 0;
167 const TypeEnvironment *newEnv = 0;
168 for ( AltList::const_iterator i = finder.get_alternatives().begin(); i != finder.get_alternatives().end(); ++i ) {
169 if ( i->expr->get_result()->size() == 1 && isIntegralType( i->expr->get_result() ) ) {
170 if ( newExpr ) {
171 throw SemanticError( "Too many interpretations for case control expression", untyped );
172 } else {
173 newExpr = i->expr->clone();
174 newEnv = &i->env;
175 } // if
176 } // if
177 } // for
178 if ( ! newExpr ) {
179 throw SemanticError( "No interpretations for case control expression", untyped );
180 } // if
181 finishExpr( newExpr, *newEnv );
182 return newExpr;
183 }
184
185 }
186
187 void Resolver::previsit( ObjectDecl *objectDecl ) {
188 Type *new_type = resolveTypeof( objectDecl->get_type(), indexer );
189 objectDecl->set_type( new_type );
190 // To handle initialization of routine pointers, e.g., int (*fp)(int) = foo(), means that class-variable
191 // initContext is changed multiple time because the LHS is analysed twice. The second analysis changes
192 // initContext because of a function type can contain object declarations in the return and parameter types. So
193 // each value of initContext is retained, so the type on the first analysis is preserved and used for selecting
194 // the RHS.
195 GuardValue( currentObject );
196 currentObject = CurrentObject( objectDecl->get_type() );
197 if ( inEnumDecl && dynamic_cast< EnumInstType * >( objectDecl->get_type() ) ) {
198 // enumerator initializers should not use the enum type to initialize, since
199 // the enum type is still incomplete at this point. Use signed int instead.
200 currentObject = CurrentObject( new BasicType( Type::Qualifiers(), BasicType::SignedInt ) );
201 }
202 }
203
204 template< typename PtrType >
205 void Resolver::handlePtrType( PtrType * type ) {
206 if ( type->get_dimension() ) {
207 CastExpr *castExpr = new CastExpr( type->get_dimension(), SymTab::SizeType->clone() );
208 Expression *newExpr = findSingleExpression( castExpr, indexer );
209 delete type->get_dimension();
210 type->set_dimension( newExpr );
211 }
212 }
213
214 void Resolver::previsit( ArrayType * at ) {
215 handlePtrType( at );
216 }
217
218 void Resolver::previsit( PointerType * pt ) {
219 handlePtrType( pt );
220 }
221
222 void Resolver::previsit( TypeDecl *typeDecl ) {
223 if ( typeDecl->get_base() ) {
224 Type *new_type = resolveTypeof( typeDecl->get_base(), indexer );
225 typeDecl->set_base( new_type );
226 } // if
227 }
228
229 void Resolver::previsit( FunctionDecl *functionDecl ) {
230#if 0
231 std::cerr << "resolver visiting functiondecl ";
232 functionDecl->print( std::cerr );
233 std::cerr << std::endl;
234#endif
235 Type *new_type = resolveTypeof( functionDecl->get_type(), indexer );
236 functionDecl->set_type( new_type );
237 GuardValue( functionReturn );
238 functionReturn = ResolvExpr::extractResultType( functionDecl->get_functionType() );
239 }
240
241
242 void Resolver::postvisit( FunctionDecl *functionDecl ) {
243 // default value expressions have an environment which shouldn't be there and trips up later passes.
244 // xxx - it might be necessary to somehow keep the information from this environment, but I can't currently
245 // see how it's useful.
246 for ( Declaration * d : functionDecl->get_functionType()->get_parameters() ) {
247 if ( ObjectDecl * obj = dynamic_cast< ObjectDecl * >( d ) ) {
248 if ( SingleInit * init = dynamic_cast< SingleInit * >( obj->get_init() ) ) {
249 delete init->get_value()->get_env();
250 init->get_value()->set_env( nullptr );
251 }
252 }
253 }
254 }
255
256 void Resolver::previsit( EnumDecl * ) {
257 // in case we decide to allow nested enums
258 GuardValue( inEnumDecl );
259 inEnumDecl = true;
260 }
261
262 void Resolver::previsit( ExprStmt *exprStmt ) {
263 visit_children = false;
264 assertf( exprStmt->get_expr(), "ExprStmt has null Expression in resolver" );
265 Expression *newExpr = findVoidExpression( exprStmt->get_expr(), indexer );
266 delete exprStmt->get_expr();
267 exprStmt->set_expr( newExpr );
268 }
269
270 void Resolver::previsit( AsmExpr *asmExpr ) {
271 visit_children = false;
272 Expression *newExpr = findVoidExpression( asmExpr->get_operand(), indexer );
273 delete asmExpr->get_operand();
274 asmExpr->set_operand( newExpr );
275 if ( asmExpr->get_inout() ) {
276 newExpr = findVoidExpression( asmExpr->get_inout(), indexer );
277 delete asmExpr->get_inout();
278 asmExpr->set_inout( newExpr );
279 } // if
280 }
281
282 void Resolver::previsit( AsmStmt *asmStmt ) {
283 visit_children = false;
284 acceptAll( asmStmt->get_input(), *visitor );
285 acceptAll( asmStmt->get_output(), *visitor );
286 }
287
288 void Resolver::previsit( IfStmt *ifStmt ) {
289 Expression *newExpr = findSingleExpression( ifStmt->get_condition(), indexer );
290 delete ifStmt->get_condition();
291 ifStmt->set_condition( newExpr );
292 }
293
294 void Resolver::previsit( WhileStmt *whileStmt ) {
295 Expression *newExpr = findSingleExpression( whileStmt->get_condition(), indexer );
296 delete whileStmt->get_condition();
297 whileStmt->set_condition( newExpr );
298 }
299
300 void Resolver::previsit( ForStmt *forStmt ) {
301 if ( forStmt->get_condition() ) {
302 Expression * newExpr = findSingleExpression( forStmt->get_condition(), indexer );
303 delete forStmt->get_condition();
304 forStmt->set_condition( newExpr );
305 } // if
306
307 if ( forStmt->get_increment() ) {
308 Expression * newExpr = findVoidExpression( forStmt->get_increment(), indexer );
309 delete forStmt->get_increment();
310 forStmt->set_increment( newExpr );
311 } // if
312 }
313
314 void Resolver::previsit( SwitchStmt *switchStmt ) {
315 GuardValue( currentObject );
316 Expression *newExpr;
317 newExpr = findIntegralExpression( switchStmt->get_condition(), indexer );
318 delete switchStmt->get_condition();
319 switchStmt->set_condition( newExpr );
320
321 currentObject = CurrentObject( newExpr->get_result() );
322 }
323
324 void Resolver::previsit( CaseStmt *caseStmt ) {
325 if ( caseStmt->get_condition() ) {
326 std::list< InitAlternative > initAlts = currentObject.getOptions();
327 assertf( initAlts.size() == 1, "SwitchStmt did not correctly resolve an integral expression." );
328 CastExpr * castExpr = new CastExpr( caseStmt->get_condition(), initAlts.front().type->clone() );
329 Expression * newExpr = findSingleExpression( castExpr, indexer );
330 castExpr = strict_dynamic_cast< CastExpr * >( newExpr );
331 caseStmt->set_condition( castExpr->get_arg() );
332 castExpr->set_arg( nullptr );
333 delete castExpr;
334 }
335 }
336
337 void Resolver::previsit( BranchStmt *branchStmt ) {
338 visit_children = false;
339 // must resolve the argument for a computed goto
340 if ( branchStmt->get_type() == BranchStmt::Goto ) { // check for computed goto statement
341 if ( Expression * arg = branchStmt->get_computedTarget() ) {
342 VoidType v = Type::Qualifiers(); // cast to void * for the alternative finder
343 PointerType pt( Type::Qualifiers(), v.clone() );
344 CastExpr * castExpr = new CastExpr( arg, pt.clone() );
345 Expression * newExpr = findSingleExpression( castExpr, indexer ); // find best expression
346 branchStmt->set_target( newExpr );
347 } // if
348 } // if
349 }
350
351 void Resolver::previsit( ReturnStmt *returnStmt ) {
352 visit_children = false;
353 if ( returnStmt->get_expr() ) {
354 CastExpr *castExpr = new CastExpr( returnStmt->get_expr(), functionReturn->clone() );
355 Expression *newExpr = findSingleExpression( castExpr, indexer );
356 delete castExpr;
357 returnStmt->set_expr( newExpr );
358 } // if
359 }
360
361 void Resolver::previsit( ThrowStmt *throwStmt ) {
362 visit_children = false;
363 // TODO: Replace *exception type with &exception type.
364 if ( throwStmt->get_expr() ) {
365 StructDecl * exception_decl =
366 indexer.lookupStruct( "__cfaehm__base_exception_t" );
367 assert( exception_decl );
368 Expression * wrapped = new CastExpr(
369 throwStmt->get_expr(),
370 new PointerType(
371 noQualifiers,
372 new StructInstType(
373 noQualifiers,
374 exception_decl
375 )
376 )
377 );
378 Expression * newExpr = findSingleExpression( wrapped, indexer );
379 throwStmt->set_expr( newExpr );
380 }
381 }
382
383 void Resolver::previsit( CatchStmt *catchStmt ) {
384 if ( catchStmt->get_cond() ) {
385 Expression * wrapped = new CastExpr(
386 catchStmt->get_cond(),
387 new BasicType( noQualifiers, BasicType::Bool )
388 );
389 catchStmt->set_cond( findSingleExpression( wrapped, indexer ) );
390 }
391 }
392
393 template< typename T >
394 bool isCharType( T t ) {
395 if ( BasicType * bt = dynamic_cast< BasicType * >( t ) ) {
396 return bt->get_kind() == BasicType::Char || bt->get_kind() == BasicType::SignedChar ||
397 bt->get_kind() == BasicType::UnsignedChar;
398 }
399 return false;
400 }
401
402 void Resolver::previsit( SingleInit *singleInit ) {
403 visit_children = false;
404 // resolve initialization using the possibilities as determined by the currentObject cursor
405 UntypedInitExpr * untyped = new UntypedInitExpr( singleInit->get_value(), currentObject.getOptions() );
406 Expression * newExpr = findSingleExpression( untyped, indexer );
407 InitExpr * initExpr = strict_dynamic_cast< InitExpr * >( newExpr );
408
409 // move cursor to the object that is actually initialized
410 currentObject.setNext( initExpr->get_designation() );
411
412 // discard InitExpr wrapper and retain relevant pieces
413 newExpr = initExpr->get_expr();
414 newExpr->set_env( initExpr->get_env() );
415 initExpr->set_expr( nullptr );
416 initExpr->set_env( nullptr );
417 delete initExpr;
418
419 // get the actual object's type (may not exactly match what comes back from the resolver due to conversions)
420 Type * initContext = currentObject.getCurrentType();
421
422 // check if actual object's type is char[]
423 if ( ArrayType * at = dynamic_cast< ArrayType * >( initContext ) ) {
424 if ( isCharType( at->get_base() ) ) {
425 // check if the resolved type is char *
426 if ( PointerType * pt = dynamic_cast< PointerType *>( newExpr->get_result() ) ) {
427 if ( isCharType( pt->get_base() ) ) {
428 // strip cast if we're initializing a char[] with a char *, e.g. char x[] = "hello";
429 CastExpr *ce = strict_dynamic_cast< CastExpr * >( newExpr );
430 newExpr = ce->get_arg();
431 ce->set_arg( nullptr );
432 delete ce;
433 }
434 }
435 }
436 }
437
438 // set initializer expr to resolved express
439 singleInit->set_value( newExpr );
440
441 // move cursor to next object in preparation for next initializer
442 currentObject.increment();
443 }
444
445 void Resolver::previsit( ListInit * listInit ) {
446 visit_children = false;
447 // move cursor into brace-enclosed initializer-list
448 currentObject.enterListInit();
449 // xxx - fix this so that the list isn't copied, iterator should be used to change current element
450 std::list<Designation *> newDesignations;
451 for ( auto p : group_iterate(listInit->get_designations(), listInit->get_initializers()) ) {
452 // iterate designations and initializers in pairs, moving the cursor to the current designated object and resolving
453 // the initializer against that object.
454 Designation * des = std::get<0>(p);
455 Initializer * init = std::get<1>(p);
456 newDesignations.push_back( currentObject.findNext( des ) );
457 init->accept( *visitor );
458 }
459 // set the set of 'resolved' designations and leave the brace-enclosed initializer-list
460 listInit->get_designations() = newDesignations; // xxx - memory management
461 currentObject.exitListInit();
462
463 // xxx - this part has not be folded into CurrentObject yet
464 // } else if ( TypeInstType * tt = dynamic_cast< TypeInstType * >( initContext ) ) {
465 // Type * base = tt->get_baseType()->get_base();
466 // if ( base ) {
467 // // know the implementation type, so try using that as the initContext
468 // ObjectDecl tmpObj( "", Type::StorageClasses(), LinkageSpec::Cforall, nullptr, base->clone(), nullptr );
469 // currentObject = &tmpObj;
470 // visit( listInit );
471 // } else {
472 // // missing implementation type -- might be an unknown type variable, so try proceeding with the current init context
473 // Parent::visit( listInit );
474 // }
475 // } else {
476 }
477
478 // ConstructorInit - fall back on C-style initializer
479 void Resolver::fallbackInit( ConstructorInit * ctorInit ) {
480 // could not find valid constructor, or found an intrinsic constructor
481 // fall back on C-style initializer
482 delete ctorInit->get_ctor();
483 ctorInit->set_ctor( NULL );
484 delete ctorInit->get_dtor();
485 ctorInit->set_dtor( NULL );
486 maybeAccept( ctorInit->get_init(), *visitor );
487 }
488
489 // needs to be callable from outside the resolver, so this is a standalone function
490 void resolveCtorInit( ConstructorInit * ctorInit, const SymTab::Indexer & indexer ) {
491 assert( ctorInit );
492 PassVisitor<Resolver> resolver( indexer );
493 ctorInit->accept( resolver );
494 }
495
496 void resolveStmtExpr( StmtExpr * stmtExpr, const SymTab::Indexer & indexer ) {
497 assert( stmtExpr );
498 PassVisitor<Resolver> resolver( indexer );
499 stmtExpr->accept( resolver );
500 }
501
502 void Resolver::previsit( ConstructorInit *ctorInit ) {
503 visit_children = false;
504 // xxx - fallback init has been removed => remove fallbackInit function and remove complexity from FixInit and remove C-init from ConstructorInit
505 maybeAccept( ctorInit->get_ctor(), *visitor );
506 maybeAccept( ctorInit->get_dtor(), *visitor );
507
508 // found a constructor - can get rid of C-style initializer
509 delete ctorInit->get_init();
510 ctorInit->set_init( NULL );
511
512 // intrinsic single parameter constructors and destructors do nothing. Since this was
513 // implicitly generated, there's no way for it to have side effects, so get rid of it
514 // to clean up generated code.
515 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->get_ctor() ) ) {
516 delete ctorInit->get_ctor();
517 ctorInit->set_ctor( NULL );
518 }
519
520 if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->get_dtor() ) ) {
521 delete ctorInit->get_dtor();
522 ctorInit->set_dtor( NULL );
523 }
524
525 // xxx - todo -- what about arrays?
526 // if ( dtor == NULL && InitTweak::isIntrinsicCallStmt( ctorInit->get_ctor() ) ) {
527 // // can reduce the constructor down to a SingleInit using the
528 // // second argument from the ctor call, since
529 // delete ctorInit->get_ctor();
530 // ctorInit->set_ctor( NULL );
531
532 // Expression * arg =
533 // ctorInit->set_init( new SingleInit( arg ) );
534 // }
535 }
536} // namespace ResolvExpr
537
538// Local Variables: //
539// tab-width: 4 //
540// mode: c++ //
541// compile-command: "make install" //
542// End: //
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