source: src/GenPoly/InstantiateGeneric.cc@ a4ca48c

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 a4ca48c was e3e16bc, checked in by Thierry Delisle <tdelisle@…>, 8 years ago

Renamed safe_dynamic_cast to strict_dynamic_cast
  • Property mode set to 100644
File size: 19.6 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2016 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// InstantiateGeneric.cc --
8//
9// Author : Aaron B. Moss
10// Created On : Thu Aug 04 18:33:00 2016
11// Last Modified By : Aaron B. Moss
12// Last Modified On : Thu Aug 04 18:33:00 2016
13// Update Count : 1
14//
15#include "InstantiateGeneric.h"
16
17#include <cassert> // for assertf, assert
18#include <iterator> // for back_inserter, inserter
19#include <list> // for list, _List_const_iterator
20#include <utility> // for move, pair
21#include <vector> // for vector
22
23#include "Common/PassVisitor.h" // for PassVisitor, WithDeclsToAdd
24#include "Common/ScopedMap.h" // for ScopedMap
25#include "Common/SemanticError.h" // for SemanticError
26#include "Common/UniqueName.h" // for UniqueName
27#include "Common/utility.h" // for deleteAll, cloneAll
28#include "GenPoly.h" // for isPolyType, typesPolyCompatible
29#include "ScopedSet.h" // for ScopedSet, ScopedSet<>::iterator
30#include "ScrubTyVars.h" // for ScrubTyVars
31#include "SynTree/Declaration.h" // for StructDecl, UnionDecl, TypeDecl
32#include "SynTree/Expression.h" // for TypeExpr, Expression
33#include "SynTree/Mutator.h" // for mutateAll
34#include "SynTree/Type.h" // for StructInstType, UnionInstType
35#include "SynTree/TypeSubstitution.h" // for TypeSubstitution
36#include "SynTree/Visitor.h" // for acceptAll
37
38
39namespace GenPoly {
40
41 /// Abstracts type equality for a list of parameter types
42 struct TypeList {
43 TypeList() : params() {}
44 TypeList( const std::list< Type* > &_params ) : params() { cloneAll(_params, params); }
45 TypeList( std::list< Type* > &&_params ) : params( _params ) {}
46
47 TypeList( const TypeList &that ) : params() { cloneAll(that.params, params); }
48 TypeList( TypeList &&that ) : params( std::move( that.params ) ) {}
49
50 /// Extracts types from a list of TypeExpr*
51 TypeList( const std::list< TypeExpr* >& _params ) : params() {
52 for ( std::list< TypeExpr* >::const_iterator param = _params.begin(); param != _params.end(); ++param ) {
53 params.push_back( (*param)->get_type()->clone() );
54 }
55 }
56
57 TypeList& operator= ( const TypeList &that ) {
58 deleteAll( params );
59
60 params.clear();
61 cloneAll( that.params, params );
62
63 return *this;
64 }
65
66 TypeList& operator= ( TypeList &&that ) {
67 deleteAll( params );
68
69 params = std::move( that.params );
70
71 return *this;
72 }
73
74 ~TypeList() { deleteAll( params ); }
75
76 bool operator== ( const TypeList& that ) const {
77 if ( params.size() != that.params.size() ) return false;
78
79 for ( std::list< Type* >::const_iterator it = params.begin(), jt = that.params.begin(); it != params.end(); ++it, ++jt ) {
80 if ( ! typesPolyCompatible( *it, *jt ) ) return false;
81 }
82 return true;
83 }
84
85 std::list< Type* > params; ///< Instantiation parameters
86 };
87
88 /// Maps a key and a TypeList to the some value, accounting for scope
89 template< typename Key, typename Value >
90 class InstantiationMap {
91 /// Wraps value for a specific (Key, TypeList) combination
92 typedef std::pair< TypeList, Value* > Instantiation;
93 /// List of TypeLists paired with their appropriate values
94 typedef std::vector< Instantiation > ValueList;
95 /// Underlying map type; maps keys to a linear list of corresponding TypeLists and values
96 typedef ScopedMap< Key*, ValueList > InnerMap;
97
98 InnerMap instantiations; ///< instantiations
99
100 public:
101 /// Starts a new scope
102 void beginScope() { instantiations.beginScope(); }
103
104 /// Ends a scope
105 void endScope() { instantiations.endScope(); }
106
107 /// Gets the value for the (key, typeList) pair, returns NULL on none such.
108 Value *lookup( Key *key, const std::list< TypeExpr* >& params ) const {
109 TypeList typeList( params );
110
111 // scan scopes for matches to the key
112 for ( typename InnerMap::const_iterator insts = instantiations.find( key ); insts != instantiations.end(); insts = instantiations.findNext( insts, key ) ) {
113 for ( typename ValueList::const_reverse_iterator inst = insts->second.rbegin(); inst != insts->second.rend(); ++inst ) {
114 if ( inst->first == typeList ) return inst->second;
115 }
116 }
117 // no matching instantiations found
118 return 0;
119 }
120
121 /// Adds a value for a (key, typeList) pair to the current scope
122 void insert( Key *key, const std::list< TypeExpr* > &params, Value *value ) {
123 auto it = instantiations.findAt( instantiations.currentScope(), key );
124 if ( it == instantiations.end() ) {
125 instantiations.insert( key, ValueList{ Instantiation{ TypeList( params ), value } } );
126 } else {
127 it->second.push_back( Instantiation{ TypeList( params ), value } );
128 }
129 }
130 };
131
132 /// Possible options for a given specialization of a generic type
133 enum class genericType {
134 dtypeStatic, ///< Concrete instantiation based solely on {d,f}type-to-void conversions
135 concrete, ///< Concrete instantiation requiring at least one parameter type
136 dynamic ///< No concrete instantiation
137 };
138
139 genericType& operator |= ( genericType& gt, const genericType& ht ) {
140 switch ( gt ) {
141 case genericType::dtypeStatic:
142 gt = ht;
143 break;
144 case genericType::concrete:
145 if ( ht == genericType::dynamic ) { gt = genericType::dynamic; }
146 break;
147 case genericType::dynamic:
148 // nothing possible
149 break;
150 }
151 return gt;
152 }
153
154 /// Mutator pass that replaces concrete instantiations of generic types with actual struct declarations, scoped appropriately
155 struct GenericInstantiator final : public WithTypeSubstitution, public WithDeclsToAdd, public WithVisitorRef<GenericInstantiator>, public WithGuards {
156 /// Map of (generic type, parameter list) pairs to concrete type instantiations
157 InstantiationMap< AggregateDecl, AggregateDecl > instantiations;
158 /// Set of types which are dtype-only generic (and therefore have static layout)
159 ScopedSet< AggregateDecl* > dtypeStatics;
160 /// Namer for concrete types
161 UniqueName typeNamer;
162 /// Should not make use of type environment to replace types of function parameter and return values.
163 bool inFunctionType = false;
164 /// Index of current member, used to recreate MemberExprs with the member from an instantiation
165 int memberIndex = -1;
166 GenericInstantiator() : instantiations(), dtypeStatics(), typeNamer("_conc_") {}
167
168 Type* postmutate( StructInstType *inst );
169 Type* postmutate( UnionInstType *inst );
170
171 // fix MemberExprs to use the member from the instantiation
172 void premutate( MemberExpr * memberExpr );
173 Expression * postmutate( MemberExpr * memberExpr );
174
175 void premutate( FunctionType * ) {
176 GuardValue( inFunctionType );
177 inFunctionType = true;
178 }
179
180 void beginScope();
181 void endScope();
182 private:
183 /// Wrap instantiation lookup for structs
184 StructDecl* lookup( StructInstType *inst, const std::list< TypeExpr* > &typeSubs ) { return (StructDecl*)instantiations.lookup( inst->get_baseStruct(), typeSubs ); }
185 /// Wrap instantiation lookup for unions
186 UnionDecl* lookup( UnionInstType *inst, const std::list< TypeExpr* > &typeSubs ) { return (UnionDecl*)instantiations.lookup( inst->get_baseUnion(), typeSubs ); }
187 /// Wrap instantiation insertion for structs
188 void insert( StructInstType *inst, const std::list< TypeExpr* > &typeSubs, StructDecl *decl ) { instantiations.insert( inst->get_baseStruct(), typeSubs, decl ); }
189 /// Wrap instantiation insertion for unions
190 void insert( UnionInstType *inst, const std::list< TypeExpr* > &typeSubs, UnionDecl *decl ) { instantiations.insert( inst->get_baseUnion(), typeSubs, decl ); }
191
192 void replaceParametersWithConcrete( std::list< Expression* >& params );
193 Type *replaceWithConcrete( Type *type, bool doClone );
194
195 /// Strips a dtype-static aggregate decl of its type parameters, marks it as stripped
196 void stripDtypeParams( AggregateDecl *base, std::list< TypeDecl* >& baseParams, const std::list< TypeExpr* >& typeSubs );
197 };
198
199 void instantiateGeneric( std::list< Declaration* > &translationUnit ) {
200 PassVisitor<GenericInstantiator> instantiator;
201 mutateAll( translationUnit, instantiator );
202 }
203
204 /// Makes substitutions of params into baseParams; returns dtypeStatic if there is a concrete instantiation based only on {d,f}type-to-void conversions,
205 /// concrete if there is a concrete instantiation requiring at least one parameter type, and dynamic if there is no concrete instantiation
206 genericType makeSubstitutions( const std::list< TypeDecl* >& baseParams, const std::list< Expression* >& params, std::list< TypeExpr* >& out ) {
207 genericType gt = genericType::dtypeStatic;
208
209 // substitute concrete types for given parameters, and incomplete types for placeholders
210 std::list< TypeDecl* >::const_iterator baseParam = baseParams.begin();
211 std::list< Expression* >::const_iterator param = params.begin();
212 for ( ; baseParam != baseParams.end() && param != params.end(); ++baseParam, ++param ) {
213 TypeExpr *paramType = dynamic_cast< TypeExpr* >( *param );
214 assert(paramType && "Aggregate parameters should be type expressions");
215
216 if ( (*baseParam)->isComplete() ) {
217 // substitute parameter for complete (otype or sized dtype) type
218 if ( isPolyType( paramType->get_type() ) ) {
219 // substitute polymorphic parameter type in to generic type
220 out.push_back( paramType->clone() );
221 gt = genericType::dynamic;
222 } else {
223 // normalize possibly dtype-static parameter type
224 out.push_back( new TypeExpr{
225 ScrubTyVars::scrubAll( paramType->get_type()->clone() ) } );
226 gt |= genericType::concrete;
227 }
228 } else switch ( (*baseParam)->get_kind() ) {
229 case TypeDecl::Dtype:
230 // can pretend that any incomplete dtype is `void`
231 out.push_back( new TypeExpr( new VoidType( Type::Qualifiers() ) ) );
232 break;
233 case TypeDecl::Ftype:
234 // can pretend that any ftype is `void (*)(void)`
235 out.push_back( new TypeExpr( new FunctionType( Type::Qualifiers(), false ) ) );
236 break;
237 case TypeDecl::Ttype:
238 assertf( false, "Ttype parameters are not currently allowed as parameters to generic types." );
239 break;
240 case TypeDecl::Any:
241 assertf( false, "otype parameters handled by baseParam->isComplete()." );
242 break;
243 }
244 }
245
246 assertf( baseParam == baseParams.end() && param == params.end(), "Type parameters should match type variables" );
247 return gt;
248 }
249
250 /// Substitutes types of members of in according to baseParams => typeSubs, appending the result to out
251 void substituteMembers( const std::list< Declaration* >& in, const std::list< TypeDecl* >& baseParams, const std::list< TypeExpr* >& typeSubs,
252 std::list< Declaration* >& out ) {
253 // substitute types into new members
254 TypeSubstitution subs( baseParams.begin(), baseParams.end(), typeSubs.begin() );
255 for ( std::list< Declaration* >::const_iterator member = in.begin(); member != in.end(); ++member ) {
256 Declaration *newMember = (*member)->clone();
257 subs.apply(newMember);
258 out.push_back( newMember );
259 }
260 }
261
262 /// Substitutes types of members according to baseParams => typeSubs, working in-place
263 void substituteMembers( std::list< Declaration* >& members, const std::list< TypeDecl* >& baseParams, const std::list< TypeExpr* >& typeSubs ) {
264 // substitute types into new members
265 TypeSubstitution subs( baseParams.begin(), baseParams.end(), typeSubs.begin() );
266 for ( std::list< Declaration* >::iterator member = members.begin(); member != members.end(); ++member ) {
267 subs.apply(*member);
268 }
269 }
270
271 /// Strips the instances's type parameters
272 void stripInstParams( ReferenceToType *inst ) {
273 deleteAll( inst->get_parameters() );
274 inst->get_parameters().clear();
275 }
276
277 void GenericInstantiator::stripDtypeParams( AggregateDecl *base, std::list< TypeDecl* >& baseParams, const std::list< TypeExpr* >& typeSubs ) {
278 substituteMembers( base->get_members(), baseParams, typeSubs );
279
280 deleteAll( baseParams );
281 baseParams.clear();
282
283 dtypeStatics.insert( base );
284 }
285
286 /// xxx - more or less copied from box -- these should be merged with those somehow...
287 void GenericInstantiator::replaceParametersWithConcrete( std::list< Expression* >& params ) {
288 for ( std::list< Expression* >::iterator param = params.begin(); param != params.end(); ++param ) {
289 TypeExpr *paramType = dynamic_cast< TypeExpr* >( *param );
290 assertf(paramType, "Aggregate parameters should be type expressions");
291 paramType->set_type( replaceWithConcrete( paramType->get_type(), false ) );
292 }
293 }
294
295 Type *GenericInstantiator::replaceWithConcrete( Type *type, bool doClone ) {
296 if ( TypeInstType *typeInst = dynamic_cast< TypeInstType * >( type ) ) {
297 if ( env && ! inFunctionType ) {
298 Type *concrete = env->lookup( typeInst->get_name() );
299 if ( concrete ) {
300 return concrete->clone();
301 }
302 else return typeInst->clone();
303 }
304 } else if ( StructInstType *structType = dynamic_cast< StructInstType* >( type ) ) {
305 if ( doClone ) {
306 structType = structType->clone();
307 }
308 replaceParametersWithConcrete( structType->get_parameters() );
309 return structType;
310 } else if ( UnionInstType *unionType = dynamic_cast< UnionInstType* >( type ) ) {
311 if ( doClone ) {
312 unionType = unionType->clone();
313 }
314 replaceParametersWithConcrete( unionType->get_parameters() );
315 return unionType;
316 }
317 return type;
318 }
319
320
321 Type* GenericInstantiator::postmutate( StructInstType *inst ) {
322 // exit early if no need for further mutation
323 if ( inst->get_parameters().empty() ) return inst;
324
325 // need to replace type variables to ensure that generic types are instantiated for the return values of polymorphic functions (in particular, for thunks, because they are not [currently] copy constructed).
326 replaceWithConcrete( inst, false );
327
328 // check for an already-instantiatiated dtype-static type
329 if ( dtypeStatics.find( inst->get_baseStruct() ) != dtypeStatics.end() ) {
330 stripInstParams( inst );
331 return inst;
332 }
333
334 // check if type can be concretely instantiated; put substitutions into typeSubs
335 assertf( inst->get_baseParameters(), "Base struct has parameters" );
336 std::list< TypeExpr* > typeSubs;
337 genericType gt = makeSubstitutions( *inst->get_baseParameters(), inst->get_parameters(), typeSubs );
338 switch ( gt ) {
339 case genericType::dtypeStatic:
340 stripDtypeParams( inst->get_baseStruct(), *inst->get_baseParameters(), typeSubs );
341 stripInstParams( inst );
342 break;
343
344 case genericType::concrete: {
345 // make concrete instantiation of generic type
346 StructDecl *concDecl = lookup( inst, typeSubs );
347 if ( ! concDecl ) {
348 // set concDecl to new type, insert type declaration into statements to add
349 concDecl = new StructDecl( typeNamer.newName( inst->get_name() ) );
350 concDecl->set_body( inst->get_baseStruct()->has_body() );
351 substituteMembers( inst->get_baseStruct()->get_members(), *inst->get_baseParameters(), typeSubs, concDecl->get_members() );
352 insert( inst, typeSubs, concDecl ); // must insert before recursion
353 concDecl->acceptMutator( *visitor ); // recursively instantiate members
354 declsToAddBefore.push_back( concDecl ); // must occur before declaration is added so that member instantiations appear first
355 }
356 StructInstType *newInst = new StructInstType( inst->get_qualifiers(), concDecl->get_name() );
357 newInst->set_baseStruct( concDecl );
358
359 delete inst;
360 inst = newInst;
361 break;
362 }
363
364 case genericType::dynamic:
365 // do nothing
366 break;
367 }
368
369 deleteAll( typeSubs );
370 return inst;
371 }
372
373 Type* GenericInstantiator::postmutate( UnionInstType *inst ) {
374 // exit early if no need for further mutation
375 if ( inst->get_parameters().empty() ) return inst;
376
377 // check for an already-instantiatiated dtype-static type
378 if ( dtypeStatics.find( inst->get_baseUnion() ) != dtypeStatics.end() ) {
379 stripInstParams( inst );
380 return inst;
381 }
382
383 // check if type can be concretely instantiated; put substitutions into typeSubs
384 assert( inst->get_baseParameters() && "Base union has parameters" );
385 std::list< TypeExpr* > typeSubs;
386 genericType gt = makeSubstitutions( *inst->get_baseParameters(), inst->get_parameters(), typeSubs );
387 switch ( gt ) {
388 case genericType::dtypeStatic:
389 stripDtypeParams( inst->get_baseUnion(), *inst->get_baseParameters(), typeSubs );
390 stripInstParams( inst );
391 break;
392
393 case genericType::concrete:
394 {
395 // make concrete instantiation of generic type
396 UnionDecl *concDecl = lookup( inst, typeSubs );
397 if ( ! concDecl ) {
398 // set concDecl to new type, insert type declaration into statements to add
399 concDecl = new UnionDecl( typeNamer.newName( inst->get_name() ) );
400 concDecl->set_body( inst->get_baseUnion()->has_body() );
401 substituteMembers( inst->get_baseUnion()->get_members(), *inst->get_baseParameters(), typeSubs, concDecl->get_members() );
402 insert( inst, typeSubs, concDecl ); // must insert before recursion
403 concDecl->acceptMutator( *visitor ); // recursively instantiate members
404 declsToAddBefore.push_back( concDecl ); // must occur before declaration is added so that member instantiations appear first
405 }
406 UnionInstType *newInst = new UnionInstType( inst->get_qualifiers(), concDecl->get_name() );
407 newInst->set_baseUnion( concDecl );
408
409 delete inst;
410 inst = newInst;
411 break;
412 }
413 case genericType::dynamic:
414 // do nothing
415 break;
416 }
417
418 deleteAll( typeSubs );
419 return inst;
420 }
421
422 namespace {
423 bool isGenericType( Type * t ) {
424 if ( StructInstType * inst = dynamic_cast< StructInstType * >( t ) ) {
425 return ! inst->parameters.empty();
426 } else if ( UnionInstType * inst = dynamic_cast< UnionInstType * >( t ) ) {
427 return ! inst->parameters.empty();
428 }
429 return false;
430 }
431
432 AggregateDecl * getAggr( Type * t ) {
433 if ( StructInstType * inst = dynamic_cast< StructInstType * >( t ) ) {
434 return inst->baseStruct;
435 } else if ( UnionInstType * inst = dynamic_cast< UnionInstType * >( t ) ) {
436 return inst->baseUnion;
437 }
438 assertf( false, "Non-aggregate type: %s", toString( t ).c_str() );
439 }
440 }
441
442 void GenericInstantiator::premutate( MemberExpr * memberExpr ) {
443 GuardValue( memberIndex );
444 memberIndex = -1;
445 if ( isGenericType( memberExpr->aggregate->result ) ) {
446 // find the location of the member
447 AggregateDecl * aggr = getAggr( memberExpr->aggregate->result );
448 std::list< Declaration * > & members = aggr->members;
449 memberIndex = std::distance( members.begin(), std::find( members.begin(), members.end(), memberExpr->member ) );
450 assertf( memberIndex < (int)members.size(), "Could not find member %s in generic type %s", toString( memberExpr->member ).c_str(), toString( memberExpr->aggregate ).c_str() );
451 }
452 }
453
454 Expression * GenericInstantiator::postmutate( MemberExpr * memberExpr ) {
455 if ( memberIndex != -1 ) {
456 // using the location from the generic type, find the member in the instantiation and rebuild the member expression
457 AggregateDecl * aggr = getAggr( memberExpr->aggregate->result );
458 assertf( memberIndex < (int)aggr->members.size(), "Instantiation somehow has fewer members than the generic type." );
459 Declaration * member = *std::next( aggr->members.begin(), memberIndex );
460 assertf( member->name == memberExpr->member->name, "Instantiation has different member order than the generic type. %s / %s", toString( member ).c_str(), toString( memberExpr->member ).c_str() );
461 DeclarationWithType * field = strict_dynamic_cast< DeclarationWithType * >( member );
462 MemberExpr * ret = new MemberExpr( field, memberExpr->aggregate->clone() );
463 std::swap( ret->env, memberExpr->env );
464 delete memberExpr;
465 return ret;
466 }
467 return memberExpr;
468 }
469
470 void GenericInstantiator::beginScope() {
471 instantiations.beginScope();
472 dtypeStatics.beginScope();
473 }
474
475 void GenericInstantiator::endScope() {
476 instantiations.endScope();
477 dtypeStatics.endScope();
478 }
479
480} // namespace GenPoly
481
482// Local Variables: //
483// tab-width: 4 //
484// mode: c++ //
485// compile-command: "make install" //
486// End: //
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