source: src/ResolvExpr/Unify.cc@ 6fa409e

new-env
Last change on this file since 6fa409e was b21c77a, checked in by Aaron Moss <a3moss@…>, 7 years ago

Merge remote-tracking branch 'origin/with_gc' into new-env
  • Property mode set to 100644
File size: 27.7 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// Unify.cc --
8//
9// Author : Richard C. Bilson
10// Created On : Sun May 17 12:27:10 2015
11// Last Modified By : Aaron B. Moss
12// Last Modified On : Mon Jun 18 11:58:00 2018
13// Update Count : 43
14//
15
16#include <cassert> // for assertf, assert
17#include <iterator> // for back_insert_iterator, back_inserter
18#include <map> // for _Rb_tree_const_iterator, _Rb_tree_i...
19#include <set> // for set
20#include <string> // for string, operator==, operator!=, bas...
21#include <utility> // for pair, move
22
23#include "Common/PassVisitor.h" // for PassVisitor
24#include "FindOpenVars.h" // for findOpenVars
25#include "Parser/LinkageSpec.h" // for C
26#include "SynTree/Constant.h" // for Constant
27#include "SynTree/Declaration.h" // for TypeDecl, TypeDecl::Data, Declarati...
28#include "SynTree/Expression.h" // for TypeExpr, Expression, ConstantExpr
29#include "SynTree/Mutator.h" // for Mutator
30#include "SynTree/Type.h" // for Type, TypeInstType, FunctionType
31#include "SynTree/Visitor.h" // for Visitor
32#include "Tuples/Tuples.h" // for isTtype
33#include "TypeEnvironment.h" // for ClassRef, AssertionSet, OpenVarSet
34#include "Unify.h"
35#include "typeops.h" // for flatten, occurs, commonType
36
37namespace SymTab {
38class Indexer;
39} // namespace SymTab
40
41// #define DEBUG
42
43namespace ResolvExpr {
44
45 struct Unify : public WithShortCircuiting {
46 Unify( Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer );
47
48 bool get_result() const { return result; }
49
50 void previsit( BaseSyntaxNode * ) { visit_children = false; }
51
52 void postvisit( VoidType * voidType );
53 void postvisit( BasicType * basicType );
54 void postvisit( PointerType * pointerType );
55 void postvisit( ArrayType * arrayType );
56 void postvisit( ReferenceType * refType );
57 void postvisit( FunctionType * functionType );
58 void postvisit( StructInstType * aggregateUseType );
59 void postvisit( UnionInstType * aggregateUseType );
60 void postvisit( EnumInstType * aggregateUseType );
61 void postvisit( TraitInstType * aggregateUseType );
62 void postvisit( TypeInstType * aggregateUseType );
63 void postvisit( TupleType * tupleType );
64 void postvisit( VarArgsType * varArgsType );
65 void postvisit( ZeroType * zeroType );
66 void postvisit( OneType * oneType );
67
68 private:
69 template< typename RefType > void handleRefType( RefType *inst, Type *other );
70 template< typename RefType > void handleGenericRefType( RefType *inst, Type *other );
71
72 bool result;
73 Type *type2; // inherited
74 TypeEnvironment &env;
75 AssertionSet &needAssertions;
76 AssertionSet &haveAssertions;
77 const OpenVarSet &openVars;
78 WidenMode widenMode;
79 const SymTab::Indexer &indexer;
80 };
81
82 /// Attempts an inexact unification of type1 and type2.
83 /// Returns false if no such unification; if the types can be unified, sets common (unless they unify exactly and have identical type qualifiers)
84 bool unifyInexact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer, Type *&common );
85 bool unifyExact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer );
86
87 bool typesCompatible( Type *first, Type *second, const SymTab::Indexer &indexer, const TypeEnvironment &env ) {
88 TypeEnvironment newEnv;
89 OpenVarSet openVars, closedVars; // added closedVars
90 AssertionSet needAssertions, haveAssertions;
91 Type *newFirst = first->clone(), *newSecond = second->clone();
92 env.apply( newFirst );
93 env.apply( newSecond );
94
95 // do we need to do this? Seems like we do, types should be able to be compatible if they
96 // have free variables that can unify
97 findOpenVars( newFirst, openVars, closedVars, needAssertions, haveAssertions, false );
98 findOpenVars( newSecond, openVars, closedVars, needAssertions, haveAssertions, true );
99
100 return unifyExact( newFirst, newSecond, newEnv, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
101 }
102
103 bool typesCompatibleIgnoreQualifiers( Type *first, Type *second, const SymTab::Indexer &indexer, const TypeEnvironment &env ) {
104 TypeEnvironment newEnv;
105 OpenVarSet openVars;
106 AssertionSet needAssertions, haveAssertions;
107 Type *newFirst = first->clone(), *newSecond = second->clone();
108 env.apply( newFirst );
109 env.apply( newSecond );
110 newFirst->get_qualifiers() = Type::Qualifiers();
111 newSecond->get_qualifiers() = Type::Qualifiers();
112/// std::cerr << "first is ";
113/// first->print( std::cerr );
114/// std::cerr << std::endl << "second is ";
115/// second->print( std::cerr );
116/// std::cerr << std::endl << "newFirst is ";
117/// newFirst->print( std::cerr );
118/// std::cerr << std::endl << "newSecond is ";
119/// newSecond->print( std::cerr );
120/// std::cerr << std::endl;
121 return unifyExact( newFirst, newSecond, newEnv, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
122 }
123
124 bool unify( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, OpenVarSet &openVars, const SymTab::Indexer &indexer ) {
125 OpenVarSet closedVars;
126 findOpenVars( type1, openVars, closedVars, needAssertions, haveAssertions, false );
127 findOpenVars( type2, openVars, closedVars, needAssertions, haveAssertions, true );
128 Type *commonType = 0;
129 return unifyInexact( type1, type2, env, needAssertions, haveAssertions, openVars, WidenMode( true, true ), indexer, commonType );
130 }
131
132 bool unify( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, OpenVarSet &openVars, const SymTab::Indexer &indexer, Type *&commonType ) {
133 OpenVarSet closedVars;
134 findOpenVars( type1, openVars, closedVars, needAssertions, haveAssertions, false );
135 findOpenVars( type2, openVars, closedVars, needAssertions, haveAssertions, true );
136 return unifyInexact( type1, type2, env, needAssertions, haveAssertions, openVars, WidenMode( true, true ), indexer, commonType );
137 }
138
139 bool unifyExact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer ) {
140#ifdef DEBUG
141 TypeEnvironment debugEnv( env );
142#endif
143 if ( type1->get_qualifiers() != type2->get_qualifiers() ) {
144 return false;
145 }
146
147 bool result;
148 TypeInstType *var1 = dynamic_cast< TypeInstType* >( type1 );
149 TypeInstType *var2 = dynamic_cast< TypeInstType* >( type2 );
150 OpenVarSet::const_iterator entry1, entry2;
151 if ( var1 ) {
152 entry1 = openVars.find( var1->get_name() );
153 } // if
154 if ( var2 ) {
155 entry2 = openVars.find( var2->get_name() );
156 } // if
157 bool isopen1 = var1 && ( entry1 != openVars.end() );
158 bool isopen2 = var2 && ( entry2 != openVars.end() );
159
160 if ( isopen1 && isopen2 && entry1->second == entry2->second ) {
161 result = env.bindVarToVar( var1, var2, entry1->second, needAssertions, haveAssertions, openVars, widenMode, indexer );
162 } else if ( isopen1 ) {
163 result = env.bindVar( var1, type2, entry1->second, needAssertions, haveAssertions, openVars, widenMode, indexer );
164 } else if ( isopen2 ) { // TODO: swap widenMode values in call, since type positions are flipped?
165 result = env.bindVar( var2, type1, entry2->second, needAssertions, haveAssertions, openVars, widenMode, indexer );
166 } else {
167 PassVisitor<Unify> comparator( type2, env, needAssertions, haveAssertions, openVars, widenMode, indexer );
168 type1->accept( comparator );
169 result = comparator.pass.get_result();
170 } // if
171#ifdef DEBUG
172 std::cerr << "============ unifyExact" << std::endl;
173 std::cerr << "type1 is ";
174 type1->print( std::cerr );
175 std::cerr << std::endl << "type2 is ";
176 type2->print( std::cerr );
177 std::cerr << std::endl << "openVars are ";
178 printOpenVarSet( openVars, std::cerr, 8 );
179 std::cerr << std::endl << "input env is " << std::endl;
180 debugEnv.print( std::cerr, 8 );
181 std::cerr << std::endl << "result env is " << std::endl;
182 env.print( std::cerr, 8 );
183 std::cerr << "result is " << result << std::endl;
184#endif
185 return result;
186 }
187
188 bool unifyExact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, OpenVarSet &openVars, const SymTab::Indexer &indexer ) {
189 return unifyExact( type1, type2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
190 }
191
192 bool unifyInexact( Type *type1, Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer, Type *&common ) {
193 Type::Qualifiers tq1 = type1->get_qualifiers(), tq2 = type2->get_qualifiers();
194 type1->get_qualifiers() = Type::Qualifiers();
195 type2->get_qualifiers() = Type::Qualifiers();
196 bool result;
197#ifdef DEBUG
198 std::cerr << "unifyInexact type 1 is ";
199 type1->print( std::cerr );
200 std::cerr << " type 2 is ";
201 type2->print( std::cerr );
202 std::cerr << std::endl;
203#endif
204 if ( ! unifyExact( type1, type2, env, needAssertions, haveAssertions, openVars, widenMode, indexer ) ) {
205#ifdef DEBUG
206 std::cerr << "unifyInexact: no exact unification found" << std::endl;
207#endif
208 if ( ( common = commonType( type1, type2, widenMode.widenFirst, widenMode.widenSecond, indexer, env, openVars ) ) ) {
209 common->get_qualifiers() = tq1 | tq2;
210#ifdef DEBUG
211 std::cerr << "unifyInexact: common type is ";
212 common->print( std::cerr );
213 std::cerr << std::endl;
214#endif
215 result = true;
216 } else {
217#ifdef DEBUG
218 std::cerr << "unifyInexact: no common type found" << std::endl;
219#endif
220 result = false;
221 } // if
222 } else {
223 if ( tq1 != tq2 ) {
224 if ( ( tq1 > tq2 || widenMode.widenFirst ) && ( tq2 > tq1 || widenMode.widenSecond ) ) {
225 common = type1->clone();
226 common->get_qualifiers() = tq1 | tq2;
227 result = true;
228 } else {
229 result = false;
230 } // if
231 } else {
232 common = type1->clone();
233 common->get_qualifiers() = tq1 | tq2;
234 result = true;
235 } // if
236 } // if
237 type1->get_qualifiers() = tq1;
238 type2->get_qualifiers() = tq2;
239 return result;
240 }
241
242 Unify::Unify( Type *type2, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, WidenMode widenMode, const SymTab::Indexer &indexer )
243 : result( false ), type2( type2 ), env( env ), needAssertions( needAssertions ), haveAssertions( haveAssertions ), openVars( openVars ), widenMode( widenMode ), indexer( indexer ) {
244 }
245
246 void Unify::postvisit( __attribute__((unused)) VoidType *voidType) {
247 result = dynamic_cast< VoidType* >( type2 );
248 }
249
250 void Unify::postvisit(BasicType *basicType) {
251 if ( BasicType *otherBasic = dynamic_cast< BasicType* >( type2 ) ) {
252 result = basicType->get_kind() == otherBasic->get_kind();
253 } // if
254 }
255
256 void markAssertionSet( AssertionSet &assertions, DeclarationWithType *assert ) {
257/// std::cerr << "assertion set is" << std::endl;
258/// printAssertionSet( assertions, std::cerr, 8 );
259/// std::cerr << "looking for ";
260/// assert->print( std::cerr );
261/// std::cerr << std::endl;
262 AssertionSet::iterator i = assertions.find( assert );
263 if ( i != assertions.end() ) {
264/// std::cerr << "found it!" << std::endl;
265 i->second.isUsed = true;
266 } // if
267 }
268
269 void markAssertions( AssertionSet &assertion1, AssertionSet &assertion2, Type *type ) {
270 for ( std::list< TypeDecl* >::const_iterator tyvar = type->get_forall().begin(); tyvar != type->get_forall().end(); ++tyvar ) {
271 for ( std::list< DeclarationWithType* >::const_iterator assert = (*tyvar)->get_assertions().begin(); assert != (*tyvar)->get_assertions().end(); ++assert ) {
272 markAssertionSet( assertion1, *assert );
273 markAssertionSet( assertion2, *assert );
274 } // for
275 } // for
276 }
277
278 void Unify::postvisit(PointerType *pointerType) {
279 if ( PointerType *otherPointer = dynamic_cast< PointerType* >( type2 ) ) {
280 result = unifyExact( pointerType->get_base(), otherPointer->get_base(), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
281 markAssertions( haveAssertions, needAssertions, pointerType );
282 markAssertions( haveAssertions, needAssertions, otherPointer );
283 } // if
284 }
285
286 void Unify::postvisit(ReferenceType *refType) {
287 if ( ReferenceType *otherRef = dynamic_cast< ReferenceType* >( type2 ) ) {
288 result = unifyExact( refType->get_base(), otherRef->get_base(), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
289 markAssertions( haveAssertions, needAssertions, refType );
290 markAssertions( haveAssertions, needAssertions, otherRef );
291 } // if
292 }
293
294 void Unify::postvisit(ArrayType *arrayType) {
295 ArrayType *otherArray = dynamic_cast< ArrayType* >( type2 );
296 // to unify, array types must both be VLA or both not VLA
297 // and must both have a dimension expression or not have a dimension
298 if ( otherArray && arrayType->get_isVarLen() == otherArray->get_isVarLen() ) {
299
300 if ( ! arrayType->get_isVarLen() && ! otherArray->get_isVarLen() &&
301 arrayType->get_dimension() != 0 && otherArray->get_dimension() != 0 ) {
302 ConstantExpr * ce1 = dynamic_cast< ConstantExpr * >( arrayType->get_dimension() );
303 ConstantExpr * ce2 = dynamic_cast< ConstantExpr * >( otherArray->get_dimension() );
304 // see C11 Reference Manual 6.7.6.2.6
305 // two array types with size specifiers that are integer constant expressions are
306 // compatible if both size specifiers have the same constant value
307 if ( ce1 && ce2 ) {
308 Constant * c1 = ce1->get_constant();
309 Constant * c2 = ce2->get_constant();
310
311 if ( c1->get_value() != c2->get_value() ) {
312 // does not unify if the dimension is different
313 return;
314 }
315 }
316 }
317
318 result = unifyExact( arrayType->get_base(), otherArray->get_base(), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
319 } // if
320 }
321
322 template< typename Iterator, typename Func >
323 Type* combineTypes( Iterator begin, Iterator end, Func & toType ) {
324 std::list< Type * > types;
325 for ( ; begin != end; ++begin ) {
326 // it's guaranteed that a ttype variable will be bound to a flat tuple, so ensure that this results in a flat tuple
327 flatten( toType( *begin ), back_inserter( types ) );
328 }
329 return new TupleType{ Type::Qualifiers(), types };
330 }
331
332 template< typename Iterator1, typename Iterator2 >
333 bool unifyDeclList( Iterator1 list1Begin, Iterator1 list1End, Iterator2 list2Begin, Iterator2 list2End, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, const SymTab::Indexer &indexer ) {
334 auto get_type = [](DeclarationWithType * dwt){ return dwt->get_type(); };
335 for ( ; list1Begin != list1End && list2Begin != list2End; ++list1Begin, ++list2Begin ) {
336 Type * t1 = (*list1Begin)->get_type();
337 Type * t2 = (*list2Begin)->get_type();
338 bool isTtype1 = Tuples::isTtype( t1 );
339 bool isTtype2 = Tuples::isTtype( t2 );
340 // xxx - assumes ttype must be last parameter
341 // xxx - there may be a nice way to refactor this, but be careful because the argument positioning might matter in some cases.
342 if ( isTtype1 && ! isTtype2 ) {
343 // combine all of the things in list2, then unify
344 return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
345 } else if ( isTtype2 && ! isTtype1 ) {
346 // combine all of the things in list1, then unify
347 return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
348 } else if ( ! unifyExact( t1, t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ) ) {
349 return false;
350 } // if
351 } // for
352 // may get to the end of one argument list before the end of the other. This is only okay when the other is a ttype
353 if ( list1Begin != list1End ) {
354 // try unifying empty tuple type with ttype
355 Type * t1 = (*list1Begin)->get_type();
356 if ( Tuples::isTtype( t1 ) ) {
357 return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
358 } else return false;
359 } else if ( list2Begin != list2End ) {
360 // try unifying empty tuple type with ttype
361 Type * t2 = (*list2Begin)->get_type();
362 if ( Tuples::isTtype( t2 ) ) {
363 return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
364 } else return false;
365 } else {
366 return true;
367 } // if
368 }
369
370 /// Finds ttypes and replaces them with their expansion, if known.
371 /// This needs to be done so that satisfying ttype assertions is easier.
372 /// If this isn't done then argument lists can have wildly different
373 /// size and structure, when they should be compatible.
374 struct TtypeExpander : public WithShortCircuiting {
375 TypeEnvironment & tenv;
376 TtypeExpander( TypeEnvironment & tenv ) : tenv( tenv ) {}
377 void premutate( TypeInstType * ) { visit_children = false; }
378 Type * postmutate( TypeInstType * typeInst ) {
379 if ( ClassRef eqvClass = tenv.lookup( typeInst->get_name() ) ) {
380 // expand ttype parameter into its actual type
381 BoundType cBound = eqvClass.get_bound();
382 if ( cBound.data.kind == TypeDecl::Ttype && cBound.type ) {
383 return cBound.type->clone();
384 }
385 }
386 return typeInst;
387 }
388 };
389
390 /// flattens a list of declarations, so that each tuple type has a single declaration.
391 /// makes use of TtypeExpander to ensure ttypes are flat as well.
392 void flattenList( std::list< DeclarationWithType * > src, std::list< DeclarationWithType * > & dst, TypeEnvironment & env ) {
393 dst.clear();
394 for ( DeclarationWithType * dcl : src ) {
395 PassVisitor<TtypeExpander> expander( env );
396 dcl->acceptMutator( expander );
397 std::list< Type * > types;
398 flatten( dcl->get_type(), back_inserter( types ) );
399 for ( Type * t : types ) {
400 // outermost const, volatile, _Atomic qualifiers in parameters should not play a role in the unification of function types, since they do not determine whether a function is callable.
401 // Note: MUST consider at least mutex qualifier, since functions can be overloaded on outermost mutex and a mutex function has different requirements than a non-mutex function.
402 t->get_qualifiers() -= Type::Qualifiers(Type::Const | Type::Volatile | Type::Atomic);
403
404 dst.push_back( new ObjectDecl( "", Type::StorageClasses(), LinkageSpec::C, nullptr, t, nullptr ) );
405 }
406 }
407 }
408
409 void Unify::postvisit(FunctionType *functionType) {
410 FunctionType *otherFunction = dynamic_cast< FunctionType* >( type2 );
411 if ( otherFunction && functionType->get_isVarArgs() == otherFunction->get_isVarArgs() ) {
412 // flatten the parameter lists for both functions so that tuple structure
413 // doesn't affect unification. Must be a clone so that the types don't change.
414 FunctionType* flatFunc = functionType->clone();
415 FunctionType* flatOther = otherFunction->clone();
416 flattenList( flatFunc->get_parameters(), flatFunc->get_parameters(), env );
417 flattenList( flatOther->get_parameters(), flatOther->get_parameters(), env );
418
419 // sizes don't have to match if ttypes are involved; need to be more precise wrt where the ttype is to prevent errors
420 if ( (flatFunc->parameters.size() == flatOther->parameters.size() && flatFunc->returnVals.size() == flatOther->returnVals.size()) || flatFunc->isTtype() || flatOther->isTtype() ) {
421 if ( unifyDeclList( flatFunc->parameters.begin(), flatFunc->parameters.end(), flatOther->parameters.begin(), flatOther->parameters.end(), env, needAssertions, haveAssertions, openVars, indexer ) ) {
422 if ( unifyDeclList( flatFunc->returnVals.begin(), flatFunc->returnVals.end(), flatOther->returnVals.begin(), flatOther->returnVals.end(), env, needAssertions, haveAssertions, openVars, indexer ) ) {
423
424 // the original types must be used in mark assertions, since pointer comparisons are used
425 markAssertions( haveAssertions, needAssertions, functionType );
426 markAssertions( haveAssertions, needAssertions, otherFunction );
427
428 result = true;
429 } // if
430 } // if
431 } // if
432 } // if
433 }
434
435 template< typename RefType >
436 void Unify::handleRefType( RefType *inst, Type *other ) {
437 // check that other type is compatible and named the same
438 RefType *otherStruct = dynamic_cast< RefType* >( other );
439 result = otherStruct && inst->name == otherStruct->name;
440 }
441
442 template< typename RefType >
443 void Unify::handleGenericRefType( RefType *inst, Type *other ) {
444 // Check that other type is compatible and named the same
445 handleRefType( inst, other );
446 if ( ! result ) return;
447 // Check that parameters of types unify, if any
448 std::list< Expression* > params = inst->parameters;
449 std::list< Expression* > otherParams = ((RefType*)other)->parameters;
450
451 std::list< Expression* >::const_iterator it = params.begin(), jt = otherParams.begin();
452 for ( ; it != params.end() && jt != otherParams.end(); ++it, ++jt ) {
453 TypeExpr *param = dynamic_cast< TypeExpr* >(*it);
454 assertf(param, "Aggregate parameters should be type expressions");
455 TypeExpr *otherParam = dynamic_cast< TypeExpr* >(*jt);
456 assertf(otherParam, "Aggregate parameters should be type expressions");
457
458 Type* paramTy = param->get_type();
459 Type* otherParamTy = otherParam->get_type();
460
461 bool tupleParam = Tuples::isTtype( paramTy );
462 bool otherTupleParam = Tuples::isTtype( otherParamTy );
463
464 if ( tupleParam && otherTupleParam ) {
465 ++it; ++jt; // skip ttype parameters for break
466 } else if ( tupleParam ) {
467 // bundle other parameters into tuple to match
468 std::list< Type * > binderTypes;
469
470 do {
471 binderTypes.push_back( otherParam->get_type()->clone() );
472 ++jt;
473
474 if ( jt == otherParams.end() ) break;
475
476 otherParam = dynamic_cast< TypeExpr* >(*jt);
477 assertf(otherParam, "Aggregate parameters should be type expressions");
478 } while (true);
479
480 otherParamTy = new TupleType{ paramTy->get_qualifiers(), binderTypes };
481 ++it; // skip ttype parameter for break
482 } else if ( otherTupleParam ) {
483 // bundle parameters into tuple to match other
484 std::list< Type * > binderTypes;
485
486 do {
487 binderTypes.push_back( param->get_type()->clone() );
488 ++it;
489
490 if ( it == params.end() ) break;
491
492 param = dynamic_cast< TypeExpr* >(*it);
493 assertf(param, "Aggregate parameters should be type expressions");
494 } while (true);
495
496 paramTy = new TupleType{ otherParamTy->get_qualifiers(), binderTypes };
497 ++jt; // skip ttype parameter for break
498 }
499
500 if ( ! unifyExact( paramTy, otherParamTy, env, needAssertions, haveAssertions, openVars, WidenMode(false, false), indexer ) ) {
501 result = false;
502 return;
503 }
504
505 // ttype parameter should be last
506 if ( tupleParam || otherTupleParam ) break;
507 }
508 result = ( it == params.end() && jt == otherParams.end() );
509 }
510
511 void Unify::postvisit(StructInstType *structInst) {
512 handleGenericRefType( structInst, type2 );
513 }
514
515 void Unify::postvisit(UnionInstType *unionInst) {
516 handleGenericRefType( unionInst, type2 );
517 }
518
519 void Unify::postvisit(EnumInstType *enumInst) {
520 handleRefType( enumInst, type2 );
521 }
522
523 void Unify::postvisit(TraitInstType *contextInst) {
524 handleRefType( contextInst, type2 );
525 }
526
527 void Unify::postvisit(TypeInstType *typeInst) {
528 assert( openVars.find( typeInst->get_name() ) == openVars.end() );
529 TypeInstType *otherInst = dynamic_cast< TypeInstType* >( type2 );
530 if ( otherInst && typeInst->get_name() == otherInst->get_name() ) {
531 result = true;
532/// } else {
533/// NamedTypeDecl *nt = indexer.lookupType( typeInst->get_name() );
534/// if ( nt ) {
535/// TypeDecl *type = dynamic_cast< TypeDecl* >( nt );
536/// assert( type );
537/// if ( type->get_base() ) {
538/// result = unifyExact( type->get_base(), typeInst, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
539/// }
540/// }
541 } // if
542 }
543
544 template< typename Iterator1, typename Iterator2 >
545 bool unifyList( Iterator1 list1Begin, Iterator1 list1End, Iterator2 list2Begin, Iterator2 list2End, TypeEnvironment &env, AssertionSet &needAssertions, AssertionSet &haveAssertions, const OpenVarSet &openVars, const SymTab::Indexer &indexer ) {
546 auto get_type = [](Type * t) { return t; };
547 for ( ; list1Begin != list1End && list2Begin != list2End; ++list1Begin, ++list2Begin ) {
548 Type * t1 = *list1Begin;
549 Type * t2 = *list2Begin;
550 bool isTtype1 = Tuples::isTtype( t1 );
551 bool isTtype2 = Tuples::isTtype( t2 );
552 // xxx - assumes ttype must be last parameter
553 // xxx - there may be a nice way to refactor this, but be careful because the argument positioning might matter in some cases.
554 if ( isTtype1 && ! isTtype2 ) {
555 // combine all of the things in list2, then unify
556 return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
557 } else if ( isTtype2 && ! isTtype1 ) {
558 // combine all of the things in list1, then unify
559 return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
560 } else if ( ! unifyExact( t1, t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer ) ) {
561 return false;
562 } // if
563
564 } // for
565 if ( list1Begin != list1End ) {
566 // try unifying empty tuple type with ttype
567 Type * t1 = *list1Begin;
568 if ( Tuples::isTtype( t1 ) ) {
569 return unifyExact( t1, combineTypes( list2Begin, list2End, get_type ), env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
570 } else return false;
571 } else if ( list2Begin != list2End ) {
572 // try unifying empty tuple type with ttype
573 Type * t2 = *list2Begin;
574 if ( Tuples::isTtype( t2 ) ) {
575 return unifyExact( combineTypes( list1Begin, list1End, get_type ), t2, env, needAssertions, haveAssertions, openVars, WidenMode( false, false ), indexer );
576 } else return false;
577 } else {
578 return true;
579 } // if
580 }
581
582 void Unify::postvisit(TupleType *tupleType) {
583 if ( TupleType *otherTuple = dynamic_cast< TupleType* >( type2 ) ) {
584 TupleType* flat1 = tupleType->clone();
585 TupleType* flat2 = otherTuple->clone();
586 std::list<Type *> types1, types2;
587
588 PassVisitor<TtypeExpander> expander( env );
589 flat1->acceptMutator( expander );
590 flat2->acceptMutator( expander );
591
592 flatten( flat1, back_inserter( types1 ) );
593 flatten( flat2, back_inserter( types2 ) );
594
595 result = unifyList( types1.begin(), types1.end(), types2.begin(), types2.end(), env, needAssertions, haveAssertions, openVars, indexer );
596 } // if
597 }
598
599 void Unify::postvisit( __attribute__((unused)) VarArgsType *varArgsType ) {
600 result = dynamic_cast< VarArgsType* >( type2 );
601 }
602
603 void Unify::postvisit( __attribute__((unused)) ZeroType *zeroType ) {
604 result = dynamic_cast< ZeroType* >( type2 );
605 }
606
607 void Unify::postvisit( __attribute__((unused)) OneType *oneType ) {
608 result = dynamic_cast< OneType* >( type2 );
609 }
610
611 // xxx - compute once and store in the FunctionType?
612 Type * extractResultType( FunctionType * function ) {
613 if ( function->get_returnVals().size() == 0 ) {
614 return new VoidType( Type::Qualifiers() );
615 } else if ( function->get_returnVals().size() == 1 ) {
616 return function->get_returnVals().front()->get_type()->clone();
617 } else {
618 std::list< Type * > types;
619 for ( DeclarationWithType * decl : function->get_returnVals() ) {
620 types.push_back( decl->get_type()->clone() );
621 } // for
622 return new TupleType( Type::Qualifiers(), types );
623 }
624 }
625} // namespace ResolvExpr
626
627// Local Variables: //
628// tab-width: 4 //
629// mode: c++ //
630// compile-command: "make install" //
631// End: //
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