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src/ResolvExpr/AlternativeFinder.cc (modified) (19 diffs)
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src/ResolvExpr/AlternativeFinder.cc
rd06c808 r62194cb 16 16 #include <algorithm> // for copy 17 17 #include <cassert> // for strict_dynamic_cast, assert, assertf 18 #include <cstddef> // for size_t 18 19 #include <iostream> // for operator<<, cerr, ostream, endl 19 20 #include <iterator> // for back_insert_iterator, back_inserter 20 21 #include <list> // for _List_iterator, list, _List_const_... 21 22 #include <map> // for _Rb_tree_iterator, map, _Rb_tree_c... 22 #include <memory> // for allocator_traits<>::value_type 23 #include <memory> // for allocator_traits<>::value_type, unique_ptr 23 24 #include <utility> // for pair 25 #include <vector> // for vector 24 26 25 27 #include "Alternative.h" // for AltList, Alternative … … 28 30 #include "Common/utility.h" // for deleteAll, printAll, CodeLocation 29 31 #include "Cost.h" // for Cost, Cost::zero, operator<<, Cost... 32 #include "ExplodedActual.h" // for ExplodedActual 30 33 #include "InitTweak/InitTweak.h" // for getFunctionName 31 34 #include "RenameVars.h" // for RenameVars, global_renamer … … 49 52 #define PRINT( text ) if ( resolvep ) { text } 50 53 //#define DEBUG_COST 54 55 using std::move; 56 57 /// copies any copyable type 58 template<typename T> 59 T copy(const T& x) { return x; } 51 60 52 61 namespace ResolvExpr { … … 186 195 printAlts( alternatives, std::cerr ); 187 196 ) 188 AltList ::iterator oldBegin = alternatives.begin();189 pruneAlternatives( alternatives.begin(), alternatives.end(), front_inserter( alternatives) );190 if ( failFast && alternatives.begin() == oldBegin) {197 AltList pruned; 198 pruneAlternatives( alternatives.begin(), alternatives.end(), back_inserter( pruned ) ); 199 if ( failFast && pruned.empty() ) { 191 200 std::ostringstream stream; 192 201 AltList winners; … … 198 207 throw SemanticError( stream.str() ); 199 208 } 200 alternatives .erase( oldBegin, alternatives.end());209 alternatives = move(pruned); 201 210 PRINT( 202 211 std::cerr << "there are " << oldsize << " alternatives before elimination" << std::endl; … … 333 342 tmpCost.incPoly( -tmpCost.get_polyCost() ); 334 343 if ( tmpCost != Cost::zero ) { 335 // if ( convCost != Cost::zero ) {336 344 Type *newType = formalType->clone(); 337 345 env.apply( newType ); … … 405 413 /// needAssertions.insert( needAssertions.end(), (*tyvar)->get_assertions().begin(), (*tyvar)->get_assertions().end() ); 406 414 } 407 }408 409 /// instantiate a single argument by matching actuals from [actualIt, actualEnd) against formalType,410 /// producing expression(s) in out and their total cost in cost.411 template< typename AltIterator, typename OutputIterator >412 bool instantiateArgument( Type * formalType, Initializer * defaultValue, AltIterator & actualIt, AltIterator actualEnd, OpenVarSet & openVars, TypeEnvironment & resultEnv, AssertionSet & resultNeed, AssertionSet & resultHave, const SymTab::Indexer & indexer, Cost & cost, OutputIterator out ) {413 if ( TupleType * tupleType = dynamic_cast< TupleType * >( formalType ) ) {414 // formalType is a TupleType - group actuals into a TupleExpr whose type unifies with the TupleType415 std::list< Expression * > exprs;416 for ( Type * type : *tupleType ) {417 if ( ! instantiateArgument( type, defaultValue, actualIt, actualEnd, openVars, resultEnv, resultNeed, resultHave, indexer, cost, back_inserter( exprs ) ) ) {418 deleteAll( exprs );419 return false;420 }421 }422 *out++ = new TupleExpr( exprs );423 } else if ( TypeInstType * ttype = Tuples::isTtype( formalType ) ) {424 // xxx - mixing default arguments with variadic??425 std::list< Expression * > exprs;426 for ( ; actualIt != actualEnd; ++actualIt ) {427 exprs.push_back( actualIt->expr->clone() );428 cost += actualIt->cost;429 }430 Expression * arg = nullptr;431 if ( exprs.size() == 1 && Tuples::isTtype( exprs.front()->get_result() ) ) {432 // the case where a ttype value is passed directly is special, e.g. for argument forwarding purposes433 // xxx - what if passing multiple arguments, last of which is ttype?434 // xxx - what would happen if unify was changed so that unifying tuple types flattened both before unifying lists? then pass in TupleType(ttype) below.435 arg = exprs.front();436 } else {437 arg = new TupleExpr( exprs );438 }439 assert( arg && arg->get_result() );440 if ( ! unify( ttype, arg->get_result(), resultEnv, resultNeed, resultHave, openVars, indexer ) ) {441 return false;442 }443 *out++ = arg;444 } else if ( actualIt != actualEnd ) {445 // both actualType and formalType are atomic (non-tuple) types - if they unify446 // then accept actual as an argument, otherwise return false (fail to instantiate argument)447 Expression * actual = actualIt->expr;448 Type * actualType = actual->get_result();449 450 PRINT(451 std::cerr << "formal type is ";452 formalType->print( std::cerr );453 std::cerr << std::endl << "actual type is ";454 actualType->print( std::cerr );455 std::cerr << std::endl;456 )457 if ( ! unify( formalType, actualType, resultEnv, resultNeed, resultHave, openVars, indexer ) ) {458 // std::cerr << "unify failed" << std::endl;459 return false;460 }461 // move the expression from the alternative to the output iterator462 *out++ = actual;463 actualIt->expr = nullptr;464 cost += actualIt->cost;465 ++actualIt;466 } else {467 // End of actuals - Handle default values468 if ( SingleInit *si = dynamic_cast<SingleInit *>( defaultValue )) {469 if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( si->get_value() ) ) {470 // so far, only constant expressions are accepted as default values471 if ( ConstantExpr *cnstexpr = dynamic_cast<ConstantExpr *>( castExpr->get_arg() ) ) {472 if ( Constant *cnst = dynamic_cast<Constant *>( cnstexpr->get_constant() ) ) {473 if ( unify( formalType, cnst->get_type(), resultEnv, resultNeed, resultHave, openVars, indexer ) ) {474 *out++ = cnstexpr->clone();475 return true;476 } // if477 } // if478 } // if479 }480 } // if481 return false;482 } // if483 return true;484 }485 486 bool AlternativeFinder::instantiateFunction( std::list< DeclarationWithType* >& formals, const AltList &actuals, bool isVarArgs, OpenVarSet& openVars, TypeEnvironment &resultEnv, AssertionSet &resultNeed, AssertionSet &resultHave, AltList & out ) {487 simpleCombineEnvironments( actuals.begin(), actuals.end(), resultEnv );488 // make sure we don't widen any existing bindings489 for ( TypeEnvironment::iterator i = resultEnv.begin(); i != resultEnv.end(); ++i ) {490 i->allowWidening = false;491 }492 resultEnv.extractOpenVars( openVars );493 494 // flatten actuals so that each actual has an atomic (non-tuple) type495 AltList exploded;496 Tuples::explode( actuals, indexer, back_inserter( exploded ) );497 498 AltList::iterator actualExpr = exploded.begin();499 AltList::iterator actualEnd = exploded.end();500 for ( DeclarationWithType * formal : formals ) {501 // match flattened actuals with formal parameters - actuals will be grouped to match502 // with formals as appropriate503 Cost cost = Cost::zero;504 std::list< Expression * > newExprs;505 ObjectDecl * obj = strict_dynamic_cast< ObjectDecl * >( formal );506 if ( ! instantiateArgument( obj->get_type(), obj->get_init(), actualExpr, actualEnd, openVars, resultEnv, resultNeed, resultHave, indexer, cost, back_inserter( newExprs ) ) ) {507 deleteAll( newExprs );508 return false;509 }510 // success - produce argument as a new alternative511 assert( newExprs.size() == 1 );512 out.push_back( Alternative( newExprs.front(), resultEnv, cost ) );513 }514 if ( actualExpr != actualEnd ) {515 // there are still actuals remaining, but we've run out of formal parameters to match against516 // this is okay only if the function is variadic517 if ( ! isVarArgs ) {518 return false;519 }520 out.splice( out.end(), exploded, actualExpr, actualEnd );521 }522 return true;523 415 } 524 416 … … 675 567 } 676 568 677 template< typename OutputIterator > 678 void AlternativeFinder::makeFunctionAlternatives( const Alternative &func, FunctionType *funcType, const AltList &actualAlt, OutputIterator out ) { 679 OpenVarSet openVars; 680 AssertionSet resultNeed, resultHave; 681 TypeEnvironment resultEnv( func.env ); 682 makeUnifiableVars( funcType, openVars, resultNeed ); 683 resultEnv.add( funcType->get_forall() ); // add all type variables as open variables now so that those not used in the parameter list are still considered open 684 AltList instantiatedActuals; // filled by instantiate function 569 /// Gets a default value from an initializer, nullptr if not present 570 ConstantExpr* getDefaultValue( Initializer* init ) { 571 if ( SingleInit* si = dynamic_cast<SingleInit*>( init ) ) { 572 if ( CastExpr* ce = dynamic_cast<CastExpr*>( si->get_value() ) ) { 573 return dynamic_cast<ConstantExpr*>( ce->get_arg() ); 574 } 575 } 576 return nullptr; 577 } 578 579 /// State to iteratively build a match of parameter expressions to arguments 580 struct ArgPack { 581 std::size_t parent; ///< Index of parent pack 582 std::unique_ptr<Expression> expr; ///< The argument stored here 583 Cost cost; ///< The cost of this argument 584 TypeEnvironment env; ///< Environment for this pack 585 AssertionSet need; ///< Assertions outstanding for this pack 586 AssertionSet have; ///< Assertions found for this pack 587 OpenVarSet openVars; ///< Open variables for this pack 588 unsigned nextArg; ///< Index of next argument in arguments list 589 unsigned tupleStart; ///< Number of tuples that start at this index 590 unsigned nextExpl; ///< Index of next exploded element 591 unsigned explAlt; ///< Index of alternative for nextExpl > 0 592 593 ArgPack() 594 : parent(0), expr(), cost(Cost::zero), env(), need(), have(), openVars(), nextArg(0), 595 tupleStart(0), nextExpl(0), explAlt(0) {} 596 597 ArgPack(const TypeEnvironment& env, const AssertionSet& need, const AssertionSet& have, 598 const OpenVarSet& openVars) 599 : parent(0), expr(), cost(Cost::zero), env(env), need(need), have(have), 600 openVars(openVars), nextArg(0), tupleStart(0), nextExpl(0), explAlt(0) {} 601 602 ArgPack(std::size_t parent, Expression* expr, TypeEnvironment&& env, AssertionSet&& need, 603 AssertionSet&& have, OpenVarSet&& openVars, unsigned nextArg, 604 unsigned tupleStart = 0, Cost cost = Cost::zero, unsigned nextExpl = 0, 605 unsigned explAlt = 0 ) 606 : parent(parent), expr(expr->clone()), cost(cost), env(move(env)), need(move(need)), 607 have(move(have)), openVars(move(openVars)), nextArg(nextArg), tupleStart(tupleStart), 608 nextExpl(nextExpl), explAlt(explAlt) {} 609 610 ArgPack(const ArgPack& o, TypeEnvironment&& env, AssertionSet&& need, AssertionSet&& have, 611 OpenVarSet&& openVars, unsigned nextArg, Cost added ) 612 : parent(o.parent), expr(o.expr ? o.expr->clone() : nullptr), cost(o.cost + added), 613 env(move(env)), need(move(need)), have(move(have)), openVars(move(openVars)), 614 nextArg(nextArg), tupleStart(o.tupleStart), nextExpl(0), explAlt(0) {} 615 616 /// true iff this pack is in the middle of an exploded argument 617 bool hasExpl() const { return nextExpl > 0; } 618 619 /// Gets the list of exploded alternatives for this pack 620 const ExplodedActual& getExpl( const ExplodedArgs& args ) const { 621 return args[nextArg-1][explAlt]; 622 } 623 624 /// Ends a tuple expression, consolidating the appropriate actuals 625 void endTuple( const std::vector<ArgPack>& packs ) { 626 // add all expressions in tuple to list, summing cost 627 std::list<Expression*> exprs; 628 const ArgPack* pack = this; 629 if ( expr ) { exprs.push_front( expr.release() ); } 630 while ( pack->tupleStart == 0 ) { 631 pack = &packs[pack->parent]; 632 exprs.push_front( pack->expr->clone() ); 633 cost += pack->cost; 634 } 635 // reset pack to appropriate tuple 636 expr.reset( new TupleExpr( exprs ) ); 637 tupleStart = pack->tupleStart - 1; 638 parent = pack->parent; 639 } 640 }; 641 642 /// Instantiates an argument to match a formal, returns false if no results left 643 bool instantiateArgument( Type* formalType, Initializer* initializer, 644 const ExplodedArgs& args, std::vector<ArgPack>& results, std::size_t& genStart, 645 const SymTab::Indexer& indexer, unsigned nTuples = 0 ) { 646 if ( TupleType* tupleType = dynamic_cast<TupleType*>( formalType ) ) { 647 // formalType is a TupleType - group actuals into a TupleExpr 648 ++nTuples; 649 for ( Type* type : *tupleType ) { 650 // xxx - dropping initializer changes behaviour from previous, but seems correct 651 if ( ! instantiateArgument( 652 type, nullptr, args, results, genStart, indexer, nTuples ) ) 653 return false; 654 nTuples = 0; 655 } 656 // re-consititute tuples for final generation 657 for ( auto i = genStart; i < results.size(); ++i ) { 658 results[i].endTuple( results ); 659 } 660 return true; 661 } else if ( TypeInstType* ttype = Tuples::isTtype( formalType ) ) { 662 // formalType is a ttype, consumes all remaining arguments 663 // xxx - mixing default arguments with variadic?? 664 665 // completed tuples; will be spliced to end of results to finish 666 std::vector<ArgPack> finalResults{}; 667 668 // iterate until all results completed 669 std::size_t genEnd; 670 ++nTuples; 671 do { 672 genEnd = results.size(); 673 674 // add another argument to results 675 for ( std::size_t i = genStart; i < genEnd; ++i ) { 676 auto nextArg = results[i].nextArg; 677 678 // use next element of exploded tuple if present 679 if ( results[i].hasExpl() ) { 680 const ExplodedActual& expl = results[i].getExpl( args ); 681 682 unsigned nextExpl = results[i].nextExpl + 1; 683 if ( nextExpl == expl.exprs.size() ) { 684 nextExpl = 0; 685 } 686 687 results.emplace_back( 688 i, expl.exprs[results[i].nextExpl].get(), copy(results[i].env), 689 copy(results[i].need), copy(results[i].have), 690 copy(results[i].openVars), nextArg, nTuples, Cost::zero, nextExpl, 691 results[i].explAlt ); 692 693 continue; 694 } 695 696 // finish result when out of arguments 697 if ( nextArg >= args.size() ) { 698 ArgPack newResult{ 699 results[i].env, results[i].need, results[i].have, 700 results[i].openVars }; 701 newResult.nextArg = nextArg; 702 Type* argType; 703 704 if ( nTuples > 0 ) { 705 // first iteration, push empty tuple expression 706 newResult.parent = i; 707 std::list<Expression*> emptyList; 708 newResult.expr.reset( new TupleExpr( emptyList ) ); 709 argType = newResult.expr->get_result(); 710 } else { 711 // clone result to collect tuple 712 newResult.parent = results[i].parent; 713 newResult.cost = results[i].cost; 714 newResult.tupleStart = results[i].tupleStart; 715 newResult.expr.reset( results[i].expr->clone() ); 716 argType = newResult.expr->get_result(); 717 718 if ( results[i].tupleStart > 0 && Tuples::isTtype( argType ) ) { 719 // the case where a ttype value is passed directly is special, 720 // e.g. for argument forwarding purposes 721 // xxx - what if passing multiple arguments, last of which is 722 // ttype? 723 // xxx - what would happen if unify was changed so that unifying 724 // tuple 725 // types flattened both before unifying lists? then pass in 726 // TupleType (ttype) below. 727 --newResult.tupleStart; 728 } else { 729 // collapse leftover arguments into tuple 730 newResult.endTuple( results ); 731 argType = newResult.expr->get_result(); 732 } 733 } 734 735 // check unification for ttype before adding to final 736 if ( unify( ttype, argType, newResult.env, newResult.need, newResult.have, 737 newResult.openVars, indexer ) ) { 738 finalResults.push_back( move(newResult) ); 739 } 740 741 continue; 742 } 743 744 // add each possible next argument 745 for ( std::size_t j = 0; j < args[nextArg].size(); ++j ) { 746 const ExplodedActual& expl = args[nextArg][j]; 747 748 // fresh copies of parent parameters for this iteration 749 TypeEnvironment env = results[i].env; 750 OpenVarSet openVars = results[i].openVars; 751 752 env.addActual( expl.env, openVars ); 753 754 // skip empty tuple arguments by (near-)cloning parent into next gen 755 if ( expl.exprs.empty() ) { 756 results.emplace_back( 757 results[i], move(env), copy(results[i].need), 758 copy(results[i].have), move(openVars), nextArg + 1, expl.cost ); 759 760 continue; 761 } 762 763 // add new result 764 results.emplace_back( 765 i, expl.exprs.front().get(), move(env), copy(results[i].need), 766 copy(results[i].have), move(openVars), nextArg + 1, 767 nTuples, expl.cost, expl.exprs.size() == 1 ? 0 : 1, j ); 768 } 769 } 770 771 // reset for next round 772 genStart = genEnd; 773 nTuples = 0; 774 } while ( genEnd != results.size() ); 775 776 // splice final results onto results 777 for ( std::size_t i = 0; i < finalResults.size(); ++i ) { 778 results.push_back( move(finalResults[i]) ); 779 } 780 return ! finalResults.empty(); 781 } 782 783 // iterate each current subresult 784 std::size_t genEnd = results.size(); 785 for ( std::size_t i = genStart; i < genEnd; ++i ) { 786 auto nextArg = results[i].nextArg; 787 788 // use remainder of exploded tuple if present 789 if ( results[i].hasExpl() ) { 790 const ExplodedActual& expl = results[i].getExpl( args ); 791 Expression* expr = expl.exprs[results[i].nextExpl].get(); 792 793 TypeEnvironment env = results[i].env; 794 AssertionSet need = results[i].need, have = results[i].have; 795 OpenVarSet openVars = results[i].openVars; 796 797 Type* actualType = expr->get_result(); 798 799 PRINT( 800 std::cerr << "formal type is "; 801 formalType->print( std::cerr ); 802 std::cerr << std::endl << "actual type is "; 803 actualType->print( std::cerr ); 804 std::cerr << std::endl; 805 ) 806 807 if ( unify( formalType, actualType, env, need, have, openVars, indexer ) ) { 808 unsigned nextExpl = results[i].nextExpl + 1; 809 if ( nextExpl == expl.exprs.size() ) { 810 nextExpl = 0; 811 } 812 813 results.emplace_back( 814 i, expr, move(env), move(need), move(have), move(openVars), nextArg, 815 nTuples, Cost::zero, nextExpl, results[i].explAlt ); 816 } 817 818 continue; 819 } 820 821 // use default initializers if out of arguments 822 if ( nextArg >= args.size() ) { 823 if ( ConstantExpr* cnstExpr = getDefaultValue( initializer ) ) { 824 if ( Constant* cnst = dynamic_cast<Constant*>( cnstExpr->get_constant() ) ) { 825 TypeEnvironment env = results[i].env; 826 AssertionSet need = results[i].need, have = results[i].have; 827 OpenVarSet openVars = results[i].openVars; 828 829 if ( unify( formalType, cnst->get_type(), env, need, have, openVars, 830 indexer ) ) { 831 results.emplace_back( 832 i, cnstExpr, move(env), move(need), move(have), 833 move(openVars), nextArg, nTuples ); 834 } 835 } 836 } 837 838 continue; 839 } 840 841 // Check each possible next argument 842 for ( std::size_t j = 0; j < args[nextArg].size(); ++j ) { 843 const ExplodedActual& expl = args[nextArg][j]; 844 845 // fresh copies of parent parameters for this iteration 846 TypeEnvironment env = results[i].env; 847 AssertionSet need = results[i].need, have = results[i].have; 848 OpenVarSet openVars = results[i].openVars; 849 850 env.addActual( expl.env, openVars ); 851 852 // skip empty tuple arguments by (near-)cloning parent into next gen 853 if ( expl.exprs.empty() ) { 854 results.emplace_back( 855 results[i], move(env), move(need), move(have), move(openVars), 856 nextArg + 1, expl.cost ); 857 858 continue; 859 } 860 861 // consider only first exploded actual 862 Expression* expr = expl.exprs.front().get(); 863 Type* actualType = expr->get_result()->clone(); 864 865 PRINT( 866 std::cerr << "formal type is "; 867 formalType->print( std::cerr ); 868 std::cerr << std::endl << "actual type is "; 869 actualType->print( std::cerr ); 870 std::cerr << std::endl; 871 ) 872 873 // attempt to unify types 874 if ( unify( formalType, actualType, env, need, have, openVars, indexer ) ) { 875 // add new result 876 results.emplace_back( 877 i, expr, move(env), move(need), move(have), move(openVars), nextArg + 1, 878 nTuples, expl.cost, expl.exprs.size() == 1 ? 0 : 1, j ); 879 } 880 } 881 } 882 883 // reset for next parameter 884 genStart = genEnd; 885 886 return genEnd != results.size(); 887 } 888 889 template<typename OutputIterator> 890 void AlternativeFinder::validateFunctionAlternative( const Alternative &func, ArgPack& result, 891 const std::vector<ArgPack>& results, OutputIterator out ) { 892 ApplicationExpr *appExpr = new ApplicationExpr( func.expr->clone() ); 893 // sum cost and accumulate actuals 894 std::list<Expression*>& args = appExpr->get_args(); 895 Cost cost = Cost::zero; 896 const ArgPack* pack = &result; 897 while ( pack->expr ) { 898 args.push_front( pack->expr->clone() ); 899 cost += pack->cost; 900 pack = &results[pack->parent]; 901 } 902 // build and validate new alternative 903 Alternative newAlt( appExpr, result.env, cost ); 904 PRINT( 905 std::cerr << "instantiate function success: " << appExpr << std::endl; 906 std::cerr << "need assertions:" << std::endl; 907 printAssertionSet( result.need, std::cerr, 8 ); 908 ) 909 inferParameters( result.need, result.have, newAlt, result.openVars, out ); 910 } 911 912 template<typename OutputIterator> 913 void AlternativeFinder::makeFunctionAlternatives( const Alternative &func, 914 FunctionType *funcType, const ExplodedArgs &args, OutputIterator out ) { 915 OpenVarSet funcOpenVars; 916 AssertionSet funcNeed, funcHave; 917 TypeEnvironment funcEnv( func.env ); 918 makeUnifiableVars( funcType, funcOpenVars, funcNeed ); 919 // add all type variables as open variables now so that those not used in the parameter 920 // list are still considered open. 921 funcEnv.add( funcType->get_forall() ); 922 685 923 if ( targetType && ! targetType->isVoid() && ! funcType->get_returnVals().empty() ) { 686 924 // attempt to narrow based on expected target type 687 925 Type * returnType = funcType->get_returnVals().front()->get_type(); 688 if ( ! unify( returnType, targetType, resultEnv, resultNeed, resultHave, openVars, indexer ) ) { 689 // unification failed, don't pursue this alternative 926 if ( ! unify( returnType, targetType, funcEnv, funcNeed, funcHave, funcOpenVars, 927 indexer ) ) { 928 // unification failed, don't pursue this function alternative 690 929 return; 691 930 } 692 931 } 693 932 694 if ( instantiateFunction( funcType->get_parameters(), actualAlt, funcType->get_isVarArgs(), openVars, resultEnv, resultNeed, resultHave, instantiatedActuals ) ) { 695 ApplicationExpr *appExpr = new ApplicationExpr( func.expr->clone() ); 696 Alternative newAlt( appExpr, resultEnv, sumCost( instantiatedActuals ) ); 697 makeExprList( instantiatedActuals, appExpr->get_args() ); 698 PRINT( 699 std::cerr << "instantiate function success: " << appExpr << std::endl; 700 std::cerr << "need assertions:" << std::endl; 701 printAssertionSet( resultNeed, std::cerr, 8 ); 702 ) 703 inferParameters( resultNeed, resultHave, newAlt, openVars, out ); 933 // iteratively build matches, one parameter at a time 934 std::vector<ArgPack> results; 935 results.push_back( ArgPack{ funcEnv, funcNeed, funcHave, funcOpenVars } ); 936 std::size_t genStart = 0; 937 938 for ( DeclarationWithType* formal : funcType->get_parameters() ) { 939 ObjectDecl* obj = strict_dynamic_cast< ObjectDecl* >( formal ); 940 if ( ! instantiateArgument( 941 obj->get_type(), obj->get_init(), args, results, genStart, indexer ) ) 942 return; 943 } 944 945 if ( funcType->get_isVarArgs() ) { 946 // append any unused arguments to vararg pack 947 std::size_t genEnd; 948 do { 949 genEnd = results.size(); 950 951 // iterate results 952 for ( std::size_t i = genStart; i < genEnd; ++i ) { 953 auto nextArg = results[i].nextArg; 954 955 // use remainder of exploded tuple if present 956 if ( results[i].hasExpl() ) { 957 const ExplodedActual& expl = results[i].getExpl( args ); 958 959 unsigned nextExpl = results[i].nextExpl + 1; 960 if ( nextExpl == expl.exprs.size() ) { 961 nextExpl = 0; 962 } 963 964 results.emplace_back( 965 i, expl.exprs[results[i].nextExpl].get(), copy(results[i].env), 966 copy(results[i].need), copy(results[i].have), 967 copy(results[i].openVars), nextArg, 0, Cost::zero, nextExpl, 968 results[i].explAlt ); 969 970 continue; 971 } 972 973 // finish result when out of arguments 974 if ( nextArg >= args.size() ) { 975 validateFunctionAlternative( func, results[i], results, out ); 976 977 continue; 978 } 979 980 // add each possible next argument 981 for ( std::size_t j = 0; j < args[nextArg].size(); ++j ) { 982 const ExplodedActual& expl = args[nextArg][j]; 983 984 // fresh copies of parent parameters for this iteration 985 TypeEnvironment env = results[i].env; 986 OpenVarSet openVars = results[i].openVars; 987 988 env.addActual( expl.env, openVars ); 989 990 // skip empty tuple arguments by (near-)cloning parent into next gen 991 if ( expl.exprs.empty() ) { 992 results.emplace_back( 993 results[i], move(env), copy(results[i].need), 994 copy(results[i].have), move(openVars), nextArg + 1, expl.cost ); 995 996 continue; 997 } 998 999 // add new result 1000 results.emplace_back( 1001 i, expl.exprs.front().get(), move(env), copy(results[i].need), 1002 copy(results[i].have), move(openVars), nextArg + 1, 0, 1003 expl.cost, expl.exprs.size() == 1 ? 0 : 1, j ); 1004 } 1005 } 1006 1007 genStart = genEnd; 1008 } while ( genEnd != results.size() ); 1009 } else { 1010 // filter out results that don't use all the arguments 1011 for ( std::size_t i = genStart; i < results.size(); ++i ) { 1012 ArgPack& result = results[i]; 1013 if ( ! result.hasExpl() && result.nextArg >= args.size() ) { 1014 validateFunctionAlternative( func, result, results, out ); 1015 } 1016 } 704 1017 } 705 1018 } … … 711 1024 if ( funcFinder.alternatives.empty() ) return; 712 1025 713 std::list< AlternativeFinder > argAlternatives; 714 findSubExprs( untypedExpr->begin_args(), untypedExpr->end_args(), back_inserter( argAlternatives ) ); 715 716 std::list< AltList > possibilities; 717 combos( argAlternatives.begin(), argAlternatives.end(), back_inserter( possibilities ) ); 1026 std::vector< AlternativeFinder > argAlternatives; 1027 findSubExprs( untypedExpr->begin_args(), untypedExpr->end_args(), 1028 back_inserter( argAlternatives ) ); 718 1029 719 1030 // take care of possible tuple assignments 720 1031 // if not tuple assignment, assignment is taken care of as a normal function call 721 Tuples::handleTupleAssignment( *this, untypedExpr, possibilities );1032 Tuples::handleTupleAssignment( *this, untypedExpr, argAlternatives ); 722 1033 723 1034 // find function operators … … 730 1041 printAlts( funcOpFinder.alternatives, std::cerr, 1 ); 731 1042 ) 1043 1044 // pre-explode arguments 1045 ExplodedArgs argExpansions; 1046 argExpansions.reserve( argAlternatives.size() ); 1047 1048 for ( const AlternativeFinder& arg : argAlternatives ) { 1049 argExpansions.emplace_back(); 1050 auto& argE = argExpansions.back(); 1051 argE.reserve( arg.alternatives.size() ); 1052 1053 for ( const Alternative& actual : arg ) { 1054 argE.emplace_back( actual, indexer ); 1055 } 1056 } 732 1057 733 1058 AltList candidates; … … 744 1069 Alternative newFunc( *func ); 745 1070 referenceToRvalueConversion( newFunc.expr ); 746 for ( std::list< AltList >::iterator actualAlt = possibilities.begin(); actualAlt != possibilities.end(); ++actualAlt ) { 747 // XXX 748 //Designators::check_alternative( function, *actualAlt ); 749 makeFunctionAlternatives( newFunc, function, *actualAlt, std::back_inserter( candidates ) ); 750 } 1071 makeFunctionAlternatives( newFunc, function, argExpansions, 1072 std::back_inserter( candidates ) ); 751 1073 } 752 1074 } else if ( TypeInstType *typeInst = dynamic_cast< TypeInstType* >( func->expr->get_result()->stripReferences() ) ) { // handle ftype (e.g. *? on function pointer) … … 756 1078 Alternative newFunc( *func ); 757 1079 referenceToRvalueConversion( newFunc.expr ); 758 for ( std::list< AltList >::iterator actualAlt = possibilities.begin(); actualAlt != possibilities.end(); ++actualAlt ) { 759 makeFunctionAlternatives( newFunc, function, *actualAlt, std::back_inserter( candidates ) ); 760 } // for 1080 makeFunctionAlternatives( newFunc, function, argExpansions, 1081 std::back_inserter( candidates ) ); 761 1082 } // if 762 1083 } // if 763 1084 } 764 765 // try each function operator ?() with the current function alternative and each of the argument combinations 766 for ( AltList::iterator funcOp = funcOpFinder.alternatives.begin(); funcOp != funcOpFinder.alternatives.end(); ++funcOp ) { 767 // check if the type is pointer to function 768 if ( PointerType *pointer = dynamic_cast< PointerType* >( funcOp->expr->get_result()->stripReferences() ) ) { 769 if ( FunctionType *function = dynamic_cast< FunctionType* >( pointer->get_base() ) ) { 1085 } catch ( SemanticError &e ) { 1086 errors.append( e ); 1087 } 1088 } // for 1089 1090 // try each function operator ?() with each function alternative 1091 if ( ! funcOpFinder.alternatives.empty() ) { 1092 // add exploded function alternatives to front of argument list 1093 std::vector<ExplodedActual> funcE; 1094 funcE.reserve( funcFinder.alternatives.size() ); 1095 for ( const Alternative& actual : funcFinder ) { 1096 funcE.emplace_back( actual, indexer ); 1097 } 1098 argExpansions.insert( argExpansions.begin(), move(funcE) ); 1099 1100 for ( AltList::iterator funcOp = funcOpFinder.alternatives.begin(); 1101 funcOp != funcOpFinder.alternatives.end(); ++funcOp ) { 1102 try { 1103 // check if type is a pointer to function 1104 if ( PointerType* pointer = dynamic_cast<PointerType*>( 1105 funcOp->expr->get_result()->stripReferences() ) ) { 1106 if ( FunctionType* function = 1107 dynamic_cast<FunctionType*>( pointer->get_base() ) ) { 770 1108 Alternative newFunc( *funcOp ); 771 1109 referenceToRvalueConversion( newFunc.expr ); 772 for ( std::list< AltList >::iterator actualAlt = possibilities.begin(); actualAlt != possibilities.end(); ++actualAlt ) { 773 AltList currentAlt; 774 currentAlt.push_back( *func ); 775 currentAlt.insert( currentAlt.end(), actualAlt->begin(), actualAlt->end() ); 776 makeFunctionAlternatives( newFunc, function, currentAlt, std::back_inserter( candidates ) ); 777 } // for 778 } // if 779 } // if 780 } // for 781 } catch ( SemanticError &e ) { 782 errors.append( e ); 783 } 784 } // for 1110 makeFunctionAlternatives( newFunc, function, argExpansions, 1111 std::back_inserter( candidates ) ); 1112 } 1113 } 1114 } catch ( SemanticError &e ) { 1115 errors.append( e ); 1116 } 1117 } 1118 } 785 1119 786 1120 // Implement SFINAE; resolution errors are only errors if there aren't any non-erroneous resolutions … … 788 1122 789 1123 // compute conversionsion costs 790 for ( Alt List::iterator withFunc = candidates.begin(); withFunc != candidates.end(); ++withFunc) {791 Cost cvtCost = computeApplicationConversionCost( *withFunc, indexer );1124 for ( Alternative& withFunc : candidates ) { 1125 Cost cvtCost = computeApplicationConversionCost( withFunc, indexer ); 792 1126 793 1127 PRINT( 794 ApplicationExpr *appExpr = strict_dynamic_cast< ApplicationExpr* >( withFunc ->expr );1128 ApplicationExpr *appExpr = strict_dynamic_cast< ApplicationExpr* >( withFunc.expr ); 795 1129 PointerType *pointer = strict_dynamic_cast< PointerType* >( appExpr->get_function()->get_result() ); 796 1130 FunctionType *function = strict_dynamic_cast< FunctionType* >( pointer->get_base() ); … … 801 1135 printAll( appExpr->get_args(), std::cerr, 8 ); 802 1136 std::cerr << "bindings are:" << std::endl; 803 withFunc ->env.print( std::cerr, 8 );1137 withFunc.env.print( std::cerr, 8 ); 804 1138 std::cerr << "cost of conversion is:" << cvtCost << std::endl; 805 1139 ) 806 1140 if ( cvtCost != Cost::infinity ) { 807 withFunc ->cvtCost = cvtCost;808 alternatives.push_back( *withFunc );1141 withFunc.cvtCost = cvtCost; 1142 alternatives.push_back( withFunc ); 809 1143 } // if 810 1144 } // for 811 1145 812 candidates.clear(); 813 candidates.splice( candidates.end(), alternatives ); 814 815 findMinCost( candidates.begin(), candidates.end(), std::back_inserter( alternatives ) ); 816 817 // function may return struct or union value, in which case we need to add alternatives for implicit 818 // conversions to each of the anonymous members, must happen after findMinCost since anon conversions 819 // are never the cheapest expression 820 for ( const Alternative & alt : alternatives ) { 1146 candidates = move(alternatives); 1147 1148 // use a new list so that alternatives are not examined by addAnonConversions twice. 1149 AltList winners; 1150 findMinCost( candidates.begin(), candidates.end(), std::back_inserter( winners ) ); 1151 1152 // function may return struct or union value, in which case we need to add alternatives 1153 // for implicitconversions to each of the anonymous members, must happen after findMinCost 1154 // since anon conversions are never the cheapest expression 1155 for ( const Alternative & alt : winners ) { 821 1156 addAnonConversions( alt ); 822 1157 } 1158 spliceBegin( alternatives, winners ); 823 1159 824 1160 if ( alternatives.empty() && targetType && ! targetType->isVoid() ) { … … 844 1180 AlternativeFinder finder( indexer, env ); 845 1181 finder.find( addressExpr->get_arg() ); 846 for ( std::list< Alternative >::iterator i = finder.alternatives.begin(); i != finder.alternatives.end(); ++i ) { 847 if ( isLvalue( i->expr ) ) { 848 alternatives.push_back( Alternative( new AddressExpr( i->expr->clone() ), i->env, i->cost ) ); 1182 for ( Alternative& alt : finder.alternatives ) { 1183 if ( isLvalue( alt.expr ) ) { 1184 alternatives.push_back( 1185 Alternative{ new AddressExpr( alt.expr->clone() ), alt.env, alt.cost } ); 849 1186 } // if 850 1187 } // for … … 852 1189 853 1190 void AlternativeFinder::visit( LabelAddressExpr * expr ) { 854 alternatives.push_back( Alternative ( expr->clone(), env, Cost::zero));1191 alternatives.push_back( Alternative{ expr->clone(), env, Cost::zero } ); 855 1192 } 856 1193 … … 894 1231 895 1232 AltList candidates; 896 for ( std::list< Alternative >::iterator i = finder.alternatives.begin(); i != finder.alternatives.end(); ++i) {1233 for ( Alternative& alt : finder.alternatives ) { 897 1234 AssertionSet needAssertions, haveAssertions; 898 1235 OpenVarSet openVars; … … 902 1239 // that are cast directly. The candidate is invalid if it has fewer results than there are types to cast 903 1240 // to. 904 int discardedValues = i->expr->get_result()->size() - castExpr->get_result()->size();1241 int discardedValues = alt.expr->get_result()->size() - castExpr->get_result()->size(); 905 1242 if ( discardedValues < 0 ) continue; 906 1243 // xxx - may need to go into tuple types and extract relevant types and use unifyList. Note that currently, this does not 907 1244 // allow casting a tuple to an atomic type (e.g. (int)([1, 2, 3])) 908 1245 // unification run for side-effects 909 unify( castExpr->get_result(), i->expr->get_result(), i->env, needAssertions, haveAssertions, openVars, indexer ); 910 Cost thisCost = castCost( i->expr->get_result(), castExpr->get_result(), indexer, i->env ); 1246 unify( castExpr->get_result(), alt.expr->get_result(), alt.env, needAssertions, 1247 haveAssertions, openVars, indexer ); 1248 Cost thisCost = castCost( alt.expr->get_result(), castExpr->get_result(), indexer, 1249 alt.env ); 911 1250 if ( thisCost != Cost::infinity ) { 912 1251 // count one safe conversion for each value that is thrown away 913 1252 thisCost.incSafe( discardedValues ); 914 Alternative newAlt( restructureCast( i->expr->clone(), toType ), i->env, i->cost, thisCost ); 915 inferParameters( needAssertions, haveAssertions, newAlt, openVars, back_inserter( candidates ) ); 1253 Alternative newAlt( restructureCast( alt.expr->clone(), toType ), alt.env, 1254 alt.cost, thisCost ); 1255 inferParameters( needAssertions, haveAssertions, newAlt, openVars, 1256 back_inserter( candidates ) ); 916 1257 } // if 917 1258 } // for … … 1200 1541 1201 1542 void AlternativeFinder::visit( UntypedTupleExpr *tupleExpr ) { 1202 std::list< AlternativeFinder > subExprAlternatives; 1203 findSubExprs( tupleExpr->get_exprs().begin(), tupleExpr->get_exprs().end(), back_inserter( subExprAlternatives ) ); 1204 std::list< AltList > possibilities; 1205 combos( subExprAlternatives.begin(), subExprAlternatives.end(), back_inserter( possibilities ) ); 1206 for ( std::list< AltList >::const_iterator i = possibilities.begin(); i != possibilities.end(); ++i ) { 1543 std::vector< AlternativeFinder > subExprAlternatives; 1544 findSubExprs( tupleExpr->get_exprs().begin(), tupleExpr->get_exprs().end(), 1545 back_inserter( subExprAlternatives ) ); 1546 std::vector< AltList > possibilities; 1547 combos( subExprAlternatives.begin(), subExprAlternatives.end(), 1548 back_inserter( possibilities ) ); 1549 for ( const AltList& alts : possibilities ) { 1207 1550 std::list< Expression * > exprs; 1208 makeExprList( *i, exprs );1551 makeExprList( alts, exprs ); 1209 1552 1210 1553 TypeEnvironment compositeEnv; 1211 simpleCombineEnvironments( i->begin(), i->end(), compositeEnv ); 1212 alternatives.push_back( Alternative( new TupleExpr( exprs ) , compositeEnv, sumCost( *i ) ) ); 1554 simpleCombineEnvironments( alts.begin(), alts.end(), compositeEnv ); 1555 alternatives.push_back( 1556 Alternative{ new TupleExpr( exprs ), compositeEnv, sumCost( alts ) } ); 1213 1557 } // for 1214 1558 }
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