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source: src/ResolvExpr/Resolver.cc@ def9d4e

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Last change on this file since def9d4e was 2fd9f24, checked in by Aaron Moss <a3moss@…>, 7 years ago
IdChain tweaks to resolver
Property mode set to `100644`
File size: 34.3 KB

Rev	Line
[a32b204]	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	//
[71f4e4f]	7	// Resolver.cc --
[a32b204]	8	//
	9	// Author : Richard C. Bilson
	10	// Created On : Sun May 17 12:17:01 2015
[59cf83b]	11	// Last Modified By : Aaron B. Moss
	12	// Last Modified On : Fri Oct 05 09:43:00 2018
	13	// Update Count : 214
[a32b204]	14	//
	15
[e3e16bc]	16	#include <cassert> // for strict_dynamic_cast, assert
[ea6332d]	17	#include <memory> // for allocator, allocator_traits<...
	18	#include <tuple> // for get
[6d6e829]	19	#include <vector> // for vector
[ea6332d]	20
	21	#include "Alternative.h" // for Alternative, AltList
	22	#include "AlternativeFinder.h" // for AlternativeFinder, resolveIn...
[a4ca48c]	23	#include "Common/PassVisitor.h" // for PassVisitor
[ea6332d]	24	#include "Common/SemanticError.h" // for SemanticError
	25	#include "Common/utility.h" // for ValueGuard, group_iterate
	26	#include "CurrentObject.h" // for CurrentObject
[0a60c04]	27	#include "InitTweak/GenInit.h"
[ea6332d]	28	#include "InitTweak/InitTweak.h" // for isIntrinsicSingleArgCallStmt
	29	#include "RenameVars.h" // for RenameVars, global_renamer
	30	#include "ResolvExpr/TypeEnvironment.h" // for TypeEnvironment
[e4d829b]	31	#include "Resolver.h"
[59cf83b]	32	#include "ResolvMode.h" // for ResolvMode
[ea6332d]	33	#include "SymTab/Autogen.h" // for SizeType
	34	#include "SymTab/Indexer.h" // for Indexer
	35	#include "SynTree/Declaration.h" // for ObjectDecl, TypeDecl, Declar...
	36	#include "SynTree/Expression.h" // for Expression, CastExpr, InitExpr
	37	#include "SynTree/Initializer.h" // for ConstructorInit, SingleInit
	38	#include "SynTree/Statement.h" // for ForStmt, Statement, BranchStmt
	39	#include "SynTree/Type.h" // for Type, BasicType, PointerType
	40	#include "SynTree/TypeSubstitution.h" // for TypeSubstitution
	41	#include "SynTree/Visitor.h" // for acceptAll, maybeAccept
[0a60c04]	42	#include "Tuples/Tuples.h"
[ea6332d]	43	#include "typeops.h" // for extractResultType
[1dcd9554]	44	#include "Unify.h" // for unify
[51b73452]	45
[d9a0e76]	46	using namespace std;
[51b73452]	47
[d9a0e76]	48	namespace ResolvExpr {
[0a60c04]	49	struct Resolver final : public WithIndexer, public WithGuards, public WithVisitorRef<Resolver>, public WithShortCircuiting, public WithStmtsToAdd {
[a4ca48c]	50	Resolver() {}
	51	Resolver( const SymTab::Indexer & other ) {
	52	indexer = other;
[1d2b64f]	53	}
[71f4e4f]	54
[a4ca48c]	55	void previsit( FunctionDecl *functionDecl );
	56	void postvisit( FunctionDecl *functionDecl );
[3c398b6]	57	void previsit( ObjectDecl *objectDecll );
[a4ca48c]	58	void previsit( EnumDecl * enumDecl );
[bd87b138]	59	void previsit( StaticAssertDecl * assertDecl );
[a4ca48c]	60
	61	void previsit( ArrayType * at );
	62	void previsit( PointerType * at );
	63
	64	void previsit( ExprStmt *exprStmt );
	65	void previsit( AsmExpr *asmExpr );
	66	void previsit( AsmStmt *asmStmt );
	67	void previsit( IfStmt *ifStmt );
	68	void previsit( WhileStmt *whileStmt );
	69	void previsit( ForStmt *forStmt );
	70	void previsit( SwitchStmt *switchStmt );
	71	void previsit( CaseStmt *caseStmt );
	72	void previsit( BranchStmt *branchStmt );
	73	void previsit( ReturnStmt *returnStmt );
	74	void previsit( ThrowStmt *throwStmt );
	75	void previsit( CatchStmt *catchStmt );
[695e00d]	76	void previsit( WaitForStmt * stmt );
[a4ca48c]	77
	78	void previsit( SingleInit *singleInit );
	79	void previsit( ListInit *listInit );
	80	void previsit( ConstructorInit *ctorInit );
[a32b204]	81	private:
[c28a038d]	82	typedef std::list< Initializer * >::iterator InitIterator;
[94b4364]	83
[40e636a]	84	template< typename PtrType >
	85	void handlePtrType( PtrType * type );
	86
[c28a038d]	87	void fallbackInit( ConstructorInit * ctorInit );
[b726084]	88
[77971f6]	89	Type * functionReturn = nullptr;
[e4d829b]	90	CurrentObject currentObject = nullptr;
[a436947]	91	bool inEnumDecl = false;
[a32b204]	92	};
[d9a0e76]	93
[2a6292d]	94	struct ResolveWithExprs : public WithIndexer, public WithGuards, public WithVisitorRef<ResolveWithExprs>, public WithShortCircuiting, public WithStmtsToAdd {
	95	void previsit( FunctionDecl * );
	96	void previsit( WithStmt * );
	97
	98	void resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts );
	99	};
	100
[a32b204]	101	void resolve( std::list< Declaration * > translationUnit ) {
[a4ca48c]	102	PassVisitor<Resolver> resolver;
[a32b204]	103	acceptAll( translationUnit, resolver );
[d9a0e76]	104	}
	105
[8b11840]	106	void resolveDecl( Declaration * decl, const SymTab::Indexer &indexer ) {
	107	PassVisitor<Resolver> resolver( indexer );
	108	maybeAccept( decl, resolver );
	109	}
	110
[c71b256]	111	namespace {
	112	struct DeleteFinder : public WithShortCircuiting {
	113	DeletedExpr * delExpr = nullptr;
	114	void previsit( DeletedExpr * expr ) {
	115	if ( delExpr ) visit_children = false;
	116	else delExpr = expr;
	117	}
	118
	119	void previsit( Expression * ) {
	120	if ( delExpr ) visit_children = false;
	121	}
	122	};
	123	}
	124
	125	DeletedExpr * findDeletedExpr( Expression * expr ) {
	126	PassVisitor<DeleteFinder> finder;
	127	expr->accept( finder );
	128	return finder.pass.delExpr;
[d9a0e76]	129	}
[a32b204]	130
	131	namespace {
[cdb990a]	132	struct StripCasts {
	133	Expression * postmutate( CastExpr * castExpr ) {
	134	if ( castExpr->isGenerated && ResolvExpr::typesCompatible( castExpr->arg->result, castExpr->result, SymTab::Indexer() ) ) {
	135	// generated cast is to the same type as its argument, so it's unnecessary -- remove it
	136	Expression * expr = castExpr->arg;
	137	castExpr->arg = nullptr;
	138	std::swap( expr->env, castExpr->env );
	139	return expr;
	140	}
	141	return castExpr;
	142	}
	143
	144	static void strip( Expression *& expr ) {
	145	PassVisitor<StripCasts> stripper;
	146	expr = expr->acceptMutator( stripper );
	147	}
	148	};
	149
	150	void finishExpr( Expression &expr, const TypeEnvironment &env, TypeSubstitution oldenv = nullptr ) {
[7664fad]	151	expr->env = oldenv ? oldenv->clone() : new TypeSubstitution;
[cdb990a]	152	env.makeSubstitution( *expr->env );
	153	StripCasts::strip( expr ); // remove unnecessary casts that may be buried in an expression
[a32b204]	154	}
[0a22cda]	155
	156	void removeExtraneousCast( Expression *& expr, const SymTab::Indexer & indexer ) {
	157	if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( expr ) ) {
	158	if ( ResolvExpr::typesCompatible( castExpr->arg->result, castExpr->result, indexer ) ) {
	159	// cast is to the same type as its argument, so it's unnecessary -- remove it
	160	expr = castExpr->arg;
	161	castExpr->arg = nullptr;
	162	std::swap( expr->env, castExpr->env );
	163	delete castExpr;
	164	}
	165	}
	166	}
[db4ecc5]	167	} // namespace
[a32b204]	168
[8f98b78]	169	namespace {
[59cf83b]	170	void findUnfinishedKindExpression(Expression * untyped, Alternative & alt, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, ResolvMode mode = ResolvMode{} ) {
[c71b256]	171	assertf( untyped, "expected a non-null expression." );
[6d6e829]	172
	173	// xxx - this isn't thread-safe, but should work until we parallelize the resolver
	174	static unsigned recursion_level = 0;
	175
	176	++recursion_level;
[8587878e]	177	TypeEnvironment env;
	178	AlternativeFinder finder( indexer, env );
[6d6e829]	179	finder.find( untyped, recursion_level == 1 ? mode.atTopLevel() : mode );
	180	--recursion_level;
[c71b256]	181
	182	#if 0
	183	if ( finder.get_alternatives().size() != 1 ) {
	184	std::cerr << "untyped expr is ";
	185	untyped->print( std::cerr );
	186	std::cerr << std::endl << "alternatives are:";
	187	for ( const Alternative & alt : finder.get_alternatives() ) {
	188	alt.print( std::cerr );
	189	} // for
	190	} // if
	191	#endif
[8587878e]	192
[6d6e829]	193	// produce filtered list of alternatives
[8587878e]	194	AltList candidates;
	195	for ( Alternative & alt : finder.get_alternatives() ) {
[c71b256]	196	if ( pred( alt ) ) {
[8587878e]	197	candidates.push_back( std::move( alt ) );
	198	}
	199	}
	200
[6d6e829]	201	// produce invalid error if no candidates
	202	if ( candidates.empty() ) {
[a16764a6]	203	SemanticError( untyped, toString( "No reasonable alternatives for ", kindStr, (kindStr != "" ? " " : ""), "expression: ") );
[6d6e829]	204	}
	205
	206	// search for cheapest candidate
	207	AltList winners;
	208	bool seen_undeleted = false;
	209	for ( unsigned i = 0; i < candidates.size(); ++i ) {
	210	int c = winners.empty() ? -1 : candidates[i].cost.compare( winners.front().cost );
	211
	212	if ( c > 0 ) continue; // skip more expensive than winner
	213
	214	if ( c < 0 ) {
	215	// reset on new cheapest
	216	seen_undeleted = ! findDeletedExpr( candidates[i].expr );
	217	winners.clear();
	218	} else /* if ( c == 0 ) */ {
	219	if ( findDeletedExpr( candidates[i].expr ) ) {
	220	// skip deleted expression if already seen one equivalent-cost not
	221	if ( seen_undeleted ) continue;
	222	} else if ( ! seen_undeleted ) {
	223	// replace list of equivalent-cost deleted expressions with one non-deleted
	224	winners.clear();
	225	seen_undeleted = true;
	226	}
	227	}
	228
[2fd9f24]	229	winners.emplace_back( std::move( candidates[i] ) );
[6d6e829]	230	}
	231
	232	// promote alternative.cvtCost to .cost
	233	// xxx - I don't know why this is done, but I'm keeping the behaviour from findMinCost
	234	for ( Alternative& winner : winners ) {
	235	winner.cost = winner.cvtCost;
	236	}
	237
	238	// produce ambiguous errors, if applicable
	239	if ( winners.size() != 1 ) {
[8587878e]	240	std::ostringstream stream;
[c71b256]	241	stream << "Cannot choose between " << winners.size() << " alternatives for " << kindStr << (kindStr != "" ? " " : "") << "expression\n";
[8587878e]	242	untyped->print( stream );
[93401f8]	243	stream << " Alternatives are:\n";
[8587878e]	244	printAlts( winners, stream, 1 );
[a16764a6]	245	SemanticError( untyped->location, stream.str() );
[8587878e]	246	}
	247
[6d6e829]	248	// single selected choice
	249	Alternative& choice = winners.front();
	250
	251	// fail on only expression deleted
	252	if ( ! seen_undeleted ) {
[2a08c25]	253	SemanticError( untyped->location, choice.expr, "Unique best alternative includes deleted identifier in " );
[c71b256]	254	}
[6d6e829]	255
	256	// xxx - check for ambiguous expressions
	257
	258	// output selected choice
[c71b256]	259	alt = std::move( choice );
	260	}
	261
	262	/// resolve `untyped` to the expression whose alternative satisfies `pred` with the lowest cost; kindStr is used for providing better error messages
[59cf83b]	263	void findKindExpression(Expression *& untyped, const SymTab::Indexer & indexer, const std::string & kindStr, std::function<bool(const Alternative &)> pred, ResolvMode mode = ResolvMode{}) {
[c71b256]	264	if ( ! untyped ) return;
	265	Alternative choice;
[59cf83b]	266	findUnfinishedKindExpression( untyped, choice, indexer, kindStr, pred, mode );
[c71b256]	267	finishExpr( choice.expr, choice.env, untyped->env );
[8587878e]	268	delete untyped;
[c71b256]	269	untyped = choice.expr;
	270	choice.expr = nullptr;
[8587878e]	271	}
	272
[c71b256]	273	bool standardAlternativeFilter( const Alternative & ) {
	274	// currently don't need to filter, under normal circumstances.
	275	// in the future, this may be useful for removing deleted expressions
	276	return true;
	277	}
	278	} // namespace
	279
	280	// used in resolveTypeof
	281	Expression * resolveInVoidContext( Expression *expr, const SymTab::Indexer &indexer ) {
	282	TypeEnvironment env;
	283	return resolveInVoidContext( expr, indexer, env );
	284	}
	285
	286	Expression * resolveInVoidContext( Expression *expr, const SymTab::Indexer &indexer, TypeEnvironment &env ) {
	287	// it's a property of the language that a cast expression has either 1 or 0 interpretations; if it has 0
	288	// interpretations, an exception has already been thrown.
	289	assertf( expr, "expected a non-null expression." );
	290
	291	static CastExpr untyped( nullptr ); // cast to void
[2a08c25]	292	untyped.location = expr->location;
[c71b256]	293
	294	// set up and resolve expression cast to void
	295	untyped.arg = expr;
	296	Alternative choice;
[59cf83b]	297	findUnfinishedKindExpression( &untyped, choice, indexer, "", standardAlternativeFilter, ResolvMode::withAdjustment() );
[c71b256]	298	CastExpr * castExpr = strict_dynamic_cast< CastExpr * >( choice.expr );
	299	env = std::move( choice.env );
	300
	301	// clean up resolved expression
	302	Expression * ret = castExpr->arg;
	303	castExpr->arg = nullptr;
	304
	305	// unlink the arg so that it isn't deleted twice at the end of the program
	306	untyped.arg = nullptr;
	307	return ret;
	308	}
	309
	310	void findVoidExpression( Expression *& untyped, const SymTab::Indexer &indexer ) {
	311	resetTyVarRenaming();
	312	TypeEnvironment env;
	313	Expression * newExpr = resolveInVoidContext( untyped, indexer, env );
	314	finishExpr( newExpr, env, untyped->env );
	315	delete untyped;
	316	untyped = newExpr;
	317	}
	318
	319	void findSingleExpression( Expression *&untyped, const SymTab::Indexer &indexer ) {
	320	findKindExpression( untyped, indexer, "", standardAlternativeFilter );
	321	}
	322
	323	void findSingleExpression( Expression & untyped, Type type, const SymTab::Indexer & indexer ) {
	324	assert( untyped && type );
[2a08c25]	325	// transfer location to generated cast for error purposes
	326	CodeLocation location = untyped->location;
[c71b256]	327	untyped = new CastExpr( untyped, type );
[2a08c25]	328	untyped->location = location;
[c71b256]	329	findSingleExpression( untyped, indexer );
	330	removeExtraneousCast( untyped, indexer );
	331	}
	332
	333	namespace {
	334	bool isIntegralType( const Alternative & alt ) {
	335	Type * type = alt.expr->result;
[a32b204]	336	if ( dynamic_cast< EnumInstType * >( type ) ) {
	337	return true;
	338	} else if ( BasicType bt = dynamic_cast< BasicType >( type ) ) {
	339	return bt->isInteger();
[89e6ffc]	340	} else if ( dynamic_cast< ZeroType* >( type ) != nullptr \|\| dynamic_cast< OneType* >( type ) != nullptr ) {
	341	return true;
[a32b204]	342	} else {
	343	return false;
	344	} // if
	345	}
[71f4e4f]	346
[08da53d]	347	void findIntegralExpression( Expression *& untyped, const SymTab::Indexer &indexer ) {
[8587878e]	348	findKindExpression( untyped, indexer, "condition", isIntegralType );
[a32b204]	349	}
	350	}
[71f4e4f]	351
[2a6292d]	352
	353	bool isStructOrUnion( const Alternative & alt ) {
	354	Type * t = alt.expr->result->stripReferences();
	355	return dynamic_cast< StructInstType * >( t ) \|\| dynamic_cast< UnionInstType * >( t );
	356	}
	357
	358	void resolveWithExprs( std::list< Declaration * > & translationUnit ) {
	359	PassVisitor<ResolveWithExprs> resolver;
	360	acceptAll( translationUnit, resolver );
	361	}
	362
	363	void ResolveWithExprs::resolveWithExprs( std::list< Expression * > & withExprs, std::list< Statement * > & newStmts ) {
	364	for ( Expression *& expr : withExprs ) {
	365	// only struct- and union-typed expressions are viable candidates
	366	findKindExpression( expr, indexer, "with statement", isStructOrUnion );
	367
	368	// if with expression might be impure, create a temporary so that it is evaluated once
	369	if ( Tuples::maybeImpure( expr ) ) {
	370	static UniqueName tmpNamer( "_with_tmp_" );
	371	ObjectDecl * tmp = ObjectDecl::newObject( tmpNamer.newName(), expr->result->clone(), new SingleInit( expr ) );
	372	expr = new VariableExpr( tmp );
	373	newStmts.push_back( new DeclStmt( tmp ) );
	374	if ( InitTweak::isConstructable( tmp->type ) ) {
	375	// generate ctor/dtor and resolve them
	376	tmp->init = InitTweak::genCtorInit( tmp );
	377	tmp->accept( *visitor );
	378	}
	379	}
	380	}
	381	}
	382
	383	void ResolveWithExprs::previsit( WithStmt * withStmt ) {
	384	resolveWithExprs( withStmt->exprs, stmtsToAddBefore );
	385	}
	386
	387	void ResolveWithExprs::previsit( FunctionDecl * functionDecl ) {
	388	{
	389	// resolve with-exprs with parameters in scope and add any newly generated declarations to the
	390	// front of the function body.
	391	auto guard = makeFuncGuard( [this]() { indexer.enterScope(); }, [this](){ indexer.leaveScope(); } );
	392	indexer.addFunctionType( functionDecl->type );
	393	std::list< Statement * > newStmts;
	394	resolveWithExprs( functionDecl->withExprs, newStmts );
	395	if ( functionDecl->statements ) {
	396	functionDecl->statements->kids.splice( functionDecl->statements->kids.begin(), newStmts );
	397	} else {
	398	assertf( functionDecl->withExprs.empty() && newStmts.empty(), "Function %s without a body has with-clause and/or generated with declarations.", functionDecl->name.c_str() );
	399	}
	400	}
	401	}
	402
[a4ca48c]	403	void Resolver::previsit( ObjectDecl *objectDecl ) {
[6d6e829]	404	// To handle initialization of routine pointers, e.g., int (*fp)(int) = foo(), means that
	405	// class-variable initContext is changed multiple time because the LHS is analysed twice.
	406	// The second analysis changes initContext because of a function type can contain object
	407	// declarations in the return and parameter types. So each value of initContext is
	408	// retained, so the type on the first analysis is preserved and used for selecting the RHS.
[a4ca48c]	409	GuardValue( currentObject );
[e4d829b]	410	currentObject = CurrentObject( objectDecl->get_type() );
	411	if ( inEnumDecl && dynamic_cast< EnumInstType * >( objectDecl->get_type() ) ) {
[a436947]	412	// enumerator initializers should not use the enum type to initialize, since
	413	// the enum type is still incomplete at this point. Use signed int instead.
[e4d829b]	414	currentObject = CurrentObject( new BasicType( Type::Qualifiers(), BasicType::SignedInt ) );
[a436947]	415	}
[bfbf97f]	416	}
	417
[40e636a]	418	template< typename PtrType >
	419	void Resolver::handlePtrType( PtrType * type ) {
	420	if ( type->get_dimension() ) {
[08da53d]	421	findSingleExpression( type->dimension, SymTab::SizeType->clone(), indexer );
[d1d17f5]	422	}
[40e636a]	423	}
	424
[a4ca48c]	425	void Resolver::previsit( ArrayType * at ) {
[40e636a]	426	handlePtrType( at );
[a32b204]	427	}
[94b4364]	428
[a4ca48c]	429	void Resolver::previsit( PointerType * pt ) {
[40e636a]	430	handlePtrType( pt );
	431	}
	432
[a4ca48c]	433	void Resolver::previsit( FunctionDecl *functionDecl ) {
[d9a0e76]	434	#if 0
[a4ca48c]	435	std::cerr << "resolver visiting functiondecl ";
	436	functionDecl->print( std::cerr );
	437	std::cerr << std::endl;
[d9a0e76]	438	#endif
[a4ca48c]	439	GuardValue( functionReturn );
[60914351]	440	functionReturn = ResolvExpr::extractResultType( functionDecl->type );
[a4ca48c]	441	}
[88d1066]	442
[a4ca48c]	443	void Resolver::postvisit( FunctionDecl *functionDecl ) {
[6d6e829]	444	// default value expressions have an environment which shouldn't be there and trips up
	445	// later passes.
	446	// xxx - it might be necessary to somehow keep the information from this environment, but I
	447	// can't currently see how it's useful.
[c28a038d]	448	for ( Declaration * d : functionDecl->type->parameters ) {
[88d1066]	449	if ( ObjectDecl * obj = dynamic_cast< ObjectDecl * >( d ) ) {
[c28a038d]	450	if ( SingleInit * init = dynamic_cast< SingleInit * >( obj->init ) ) {
	451	delete init->value->env;
	452	init->value->env = nullptr;
[88d1066]	453	}
	454	}
	455	}
[a32b204]	456	}
[51b73452]	457
[a4ca48c]	458	void Resolver::previsit( EnumDecl * ) {
[a436947]	459	// in case we decide to allow nested enums
[a4ca48c]	460	GuardValue( inEnumDecl );
[a436947]	461	inEnumDecl = true;
	462	}
	463
[bd87b138]	464	void Resolver::previsit( StaticAssertDecl * assertDecl ) {
	465	findIntegralExpression( assertDecl->condition, indexer );
	466	}
	467
[a4ca48c]	468	void Resolver::previsit( ExprStmt *exprStmt ) {
	469	visit_children = false;
[08da53d]	470	assertf( exprStmt->expr, "ExprStmt has null Expression in resolver" );
	471	findVoidExpression( exprStmt->expr, indexer );
[a32b204]	472	}
[51b73452]	473
[a4ca48c]	474	void Resolver::previsit( AsmExpr *asmExpr ) {
	475	visit_children = false;
[08da53d]	476	findVoidExpression( asmExpr->operand, indexer );
[7f5566b]	477	if ( asmExpr->get_inout() ) {
[08da53d]	478	findVoidExpression( asmExpr->inout, indexer );
[7f5566b]	479	} // if
	480	}
	481
[a4ca48c]	482	void Resolver::previsit( AsmStmt *asmStmt ) {
	483	visit_children = false;
	484	acceptAll( asmStmt->get_input(), *visitor );
	485	acceptAll( asmStmt->get_output(), *visitor );
[7f5566b]	486	}
	487
[a4ca48c]	488	void Resolver::previsit( IfStmt *ifStmt ) {
[8587878e]	489	findIntegralExpression( ifStmt->condition, indexer );
[a32b204]	490	}
[51b73452]	491
[a4ca48c]	492	void Resolver::previsit( WhileStmt *whileStmt ) {
[8587878e]	493	findIntegralExpression( whileStmt->condition, indexer );
[a32b204]	494	}
[51b73452]	495
[a4ca48c]	496	void Resolver::previsit( ForStmt *forStmt ) {
[08da53d]	497	if ( forStmt->condition ) {
[8587878e]	498	findIntegralExpression( forStmt->condition, indexer );
[a32b204]	499	} // if
[71f4e4f]	500
[08da53d]	501	if ( forStmt->increment ) {
	502	findVoidExpression( forStmt->increment, indexer );
[a32b204]	503	} // if
	504	}
[51b73452]	505
[a4ca48c]	506	void Resolver::previsit( SwitchStmt *switchStmt ) {
	507	GuardValue( currentObject );
[08da53d]	508	findIntegralExpression( switchStmt->condition, indexer );
[71f4e4f]	509
[08da53d]	510	currentObject = CurrentObject( switchStmt->condition->result );
[a32b204]	511	}
[51b73452]	512
[a4ca48c]	513	void Resolver::previsit( CaseStmt *caseStmt ) {
[cdb990a]	514	if ( caseStmt->condition ) {
[e4d829b]	515	std::list< InitAlternative > initAlts = currentObject.getOptions();
	516	assertf( initAlts.size() == 1, "SwitchStmt did not correctly resolve an integral expression." );
[08da53d]	517	// must remove cast from case statement because RangeExpr cannot be cast.
	518	Expression * newExpr = new CastExpr( caseStmt->condition, initAlts.front().type->clone() );
	519	findSingleExpression( newExpr, indexer );
[cdb990a]	520	// case condition cannot have a cast in C, so it must be removed, regardless of whether it performs a conversion.
	521	// Ideally we would perform the conversion internally here.
	522	if ( CastExpr * castExpr = dynamic_cast< CastExpr * >( newExpr ) ) {
	523	newExpr = castExpr->arg;
	524	castExpr->arg = nullptr;
	525	std::swap( newExpr->env, castExpr->env );
	526	delete castExpr;
	527	}
	528	caseStmt->condition = newExpr;
[32b8144]	529	}
[a32b204]	530	}
[51b73452]	531
[a4ca48c]	532	void Resolver::previsit( BranchStmt *branchStmt ) {
	533	visit_children = false;
[de62360d]	534	// must resolve the argument for a computed goto
	535	if ( branchStmt->get_type() == BranchStmt::Goto ) { // check for computed goto statement
[08da53d]	536	if ( branchStmt->computedTarget ) {
	537	// computed goto argument is void *
	538	findSingleExpression( branchStmt->computedTarget, new PointerType( Type::Qualifiers(), new VoidType( Type::Qualifiers() ) ), indexer );
[de62360d]	539	} // if
	540	} // if
	541	}
	542
[a4ca48c]	543	void Resolver::previsit( ReturnStmt *returnStmt ) {
	544	visit_children = false;
[08da53d]	545	if ( returnStmt->expr ) {
	546	findSingleExpression( returnStmt->expr, functionReturn->clone(), indexer );
[a32b204]	547	} // if
	548	}
[51b73452]	549
[a4ca48c]	550	void Resolver::previsit( ThrowStmt *throwStmt ) {
	551	visit_children = false;
[cbce272]	552	// TODO: Replace *exception type with &exception type.
[307a732]	553	if ( throwStmt->get_expr() ) {
[cbce272]	554	StructDecl * exception_decl =
[36982fc]	555	indexer.lookupStruct( "__cfaabi_ehm__base_exception_t" );
[cbce272]	556	assert( exception_decl );
[08da53d]	557	Type * exceptType = new PointerType( noQualifiers, new StructInstType( noQualifiers, exception_decl ) );
	558	findSingleExpression( throwStmt->expr, exceptType, indexer );
[307a732]	559	}
	560	}
	561
[a4ca48c]	562	void Resolver::previsit( CatchStmt *catchStmt ) {
[08da53d]	563	if ( catchStmt->cond ) {
	564	findSingleExpression( catchStmt->cond, new BasicType( noQualifiers, BasicType::Bool ), indexer );
[cbce272]	565	}
	566	}
	567
[1dcd9554]	568	template< typename iterator_t >
	569	inline bool advance_to_mutex( iterator_t & it, const iterator_t & end ) {
	570	while( it != end && !(*it)->get_type()->get_mutex() ) {
	571	it++;
	572	}
	573
	574	return it != end;
	575	}
	576
[695e00d]	577	void Resolver::previsit( WaitForStmt * stmt ) {
[8f98b78]	578	visit_children = false;
[1dcd9554]	579
	580	// Resolve all clauses first
	581	for( auto& clause : stmt->clauses ) {
	582
	583	TypeEnvironment env;
[8f98b78]	584	AlternativeFinder funcFinder( indexer, env );
[1dcd9554]	585
	586	// Find all alternatives for a function in canonical form
	587	funcFinder.findWithAdjustment( clause.target.function );
	588
	589	if ( funcFinder.get_alternatives().empty() ) {
	590	stringstream ss;
	591	ss << "Use of undeclared indentifier '";
	592	ss << strict_dynamic_cast<NameExpr*>( clause.target.function )->name;
	593	ss << "' in call to waitfor";
[a16764a6]	594	SemanticError( stmt->location, ss.str() );
[1dcd9554]	595	}
	596
[b9f383f]	597	if(clause.target.arguments.empty()) {
	598	SemanticError( stmt->location, "Waitfor clause must have at least one mutex parameter");
	599	}
	600
[1dcd9554]	601	// Find all alternatives for all arguments in canonical form
[bd4f2e9]	602	std::vector< AlternativeFinder > argAlternatives;
[1dcd9554]	603	funcFinder.findSubExprs( clause.target.arguments.begin(), clause.target.arguments.end(), back_inserter( argAlternatives ) );
	604
	605	// List all combinations of arguments
[bd4f2e9]	606	std::vector< AltList > possibilities;
[1dcd9554]	607	combos( argAlternatives.begin(), argAlternatives.end(), back_inserter( possibilities ) );
	608
	609	AltList func_candidates;
	610	std::vector< AltList > args_candidates;
	611
	612	// For every possible function :
	613	// try matching the arguments to the parameters
	614	// not the other way around because we have more arguments than parameters
[a16764a6]	615	SemanticErrorException errors;
[1dcd9554]	616	for ( Alternative & func : funcFinder.get_alternatives() ) {
	617	try {
	618	PointerType * pointer = dynamic_cast< PointerType* >( func.expr->get_result()->stripReferences() );
	619	if( !pointer ) {
[a16764a6]	620	SemanticError( func.expr->get_result(), "candidate not viable: not a pointer type\n" );
[1dcd9554]	621	}
	622
	623	FunctionType * function = dynamic_cast< FunctionType* >( pointer->get_base() );
	624	if( !function ) {
[a16764a6]	625	SemanticError( pointer->get_base(), "candidate not viable: not a function type\n" );
[1dcd9554]	626	}
	627
	628
	629	{
	630	auto param = function->parameters.begin();
	631	auto param_end = function->parameters.end();
	632
	633	if( !advance_to_mutex( param, param_end ) ) {
[a16764a6]	634	SemanticError(function, "candidate function not viable: no mutex parameters\n");
[1dcd9554]	635	}
	636	}
	637
	638	Alternative newFunc( func );
	639	// Strip reference from function
[a181494]	640	referenceToRvalueConversion( newFunc.expr, newFunc.cost );
[1dcd9554]	641
	642	// For all the set of arguments we have try to match it with the parameter of the current function alternative
	643	for ( auto & argsList : possibilities ) {
	644
	645	try {
	646	// Declare data structures need for resolution
	647	OpenVarSet openVars;
	648	AssertionSet resultNeed, resultHave;
[6f326b1]	649	TypeEnvironment resultEnv( func.env );
	650	makeUnifiableVars( function, openVars, resultNeed );
	651	// add all type variables as open variables now so that those not used in the parameter
	652	// list are still considered open.
	653	resultEnv.add( function->forall );
[1dcd9554]	654
	655	// Load type variables from arguemnts into one shared space
	656	simpleCombineEnvironments( argsList.begin(), argsList.end(), resultEnv );
	657
	658	// Make sure we don't widen any existing bindings
[d286cf68]	659	resultEnv.forbidWidening();
[c5283ba]	660
[1dcd9554]	661	// Find any unbound type variables
	662	resultEnv.extractOpenVars( openVars );
	663
	664	auto param = function->parameters.begin();
	665	auto param_end = function->parameters.end();
	666
[c5283ba]	667	int n_mutex_param = 0;
[b9f383f]	668
[1dcd9554]	669	// For every arguments of its set, check if it matches one of the parameter
	670	// The order is important
	671	for( auto & arg : argsList ) {
	672
	673	// Ignore non-mutex arguments
	674	if( !advance_to_mutex( param, param_end ) ) {
	675	// We ran out of parameters but still have arguments
	676	// this function doesn't match
[c5283ba]	677	SemanticError( function, toString("candidate function not viable: too many mutex arguments, expected ", n_mutex_param, "\n" ));
[1dcd9554]	678	}
	679
[c5283ba]	680	n_mutex_param++;
[b9f383f]	681
[1dcd9554]	682	// Check if the argument matches the parameter type in the current scope
[b9f383f]	683	if( ! unify( arg.expr->get_result(), (*param)->get_type(), resultEnv, resultNeed, resultHave, openVars, this->indexer ) ) {
[1dcd9554]	684	// Type doesn't match
	685	stringstream ss;
	686	ss << "candidate function not viable: no known convertion from '";
	687	(*param)->get_type()->print( ss );
[b9f383f]	688	ss << "' to '";
	689	arg.expr->get_result()->print( ss );
[5248789]	690	ss << "' with env '";
	691	resultEnv.print(ss);
[1dcd9554]	692	ss << "'\n";
[a16764a6]	693	SemanticError( function, ss.str() );
[1dcd9554]	694	}
	695
	696	param++;
	697	}
	698
	699	// All arguments match !
	700
	701	// Check if parameters are missing
	702	if( advance_to_mutex( param, param_end ) ) {
[c5283ba]	703	do {
	704	n_mutex_param++;
	705	param++;
	706	} while( advance_to_mutex( param, param_end ) );
	707
[1dcd9554]	708	// We ran out of arguments but still have parameters left
	709	// this function doesn't match
[c5283ba]	710	SemanticError( function, toString("candidate function not viable: too few mutex arguments, expected ", n_mutex_param, "\n" ));
[1dcd9554]	711	}
	712
	713	// All parameters match !
	714
	715	// Finish the expressions to tie in the proper environments
	716	finishExpr( newFunc.expr, resultEnv );
	717	for( Alternative & alt : argsList ) {
	718	finishExpr( alt.expr, resultEnv );
	719	}
	720
	721	// This is a match store it and save it for later
	722	func_candidates.push_back( newFunc );
	723	args_candidates.push_back( argsList );
	724
	725	}
[a16764a6]	726	catch( SemanticErrorException &e ) {
[1dcd9554]	727	errors.append( e );
	728	}
	729	}
	730	}
[a16764a6]	731	catch( SemanticErrorException &e ) {
[1dcd9554]	732	errors.append( e );
	733	}
	734	}
	735
	736	// Make sure we got the right number of arguments
[a16764a6]	737	if( func_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for function in call to waitfor" ); top.append( errors ); throw top; }
	738	if( args_candidates.empty() ) { SemanticErrorException top( stmt->location, "No alternatives for arguments in call to waitfor" ); top.append( errors ); throw top; }
	739	if( func_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous function in call to waitfor" ); top.append( errors ); throw top; }
	740	if( args_candidates.size() > 1 ) { SemanticErrorException top( stmt->location, "Ambiguous arguments in call to waitfor" ); top.append( errors ); throw top; }
[c71b256]	741	// TODO: need to use findDeletedExpr to ensure no deleted identifiers are used.
[1dcd9554]	742
	743	// Swap the results from the alternative with the unresolved values.
	744	// Alternatives will handle deletion on destruction
	745	std::swap( clause.target.function, func_candidates.front().expr );
	746	for( auto arg_pair : group_iterate( clause.target.arguments, args_candidates.front() ) ) {
	747	std::swap ( std::get<0>( arg_pair), std::get<1>( arg_pair).expr );
	748	}
	749
	750	// Resolve the conditions as if it were an IfStmt
	751	// Resolve the statments normally
[08da53d]	752	findSingleExpression( clause.condition, this->indexer );
[8f98b78]	753	clause.statement->accept( *visitor );
[1dcd9554]	754	}
	755
	756
	757	if( stmt->timeout.statement ) {
	758	// Resolve the timeout as an size_t for now
	759	// Resolve the conditions as if it were an IfStmt
	760	// Resolve the statments normally
[08da53d]	761	findSingleExpression( stmt->timeout.time, new BasicType( noQualifiers, BasicType::LongLongUnsignedInt ), this->indexer );
	762	findSingleExpression( stmt->timeout.condition, this->indexer );
[8f98b78]	763	stmt->timeout.statement->accept( *visitor );
[1dcd9554]	764	}
	765
	766	if( stmt->orelse.statement ) {
	767	// Resolve the conditions as if it were an IfStmt
	768	// Resolve the statments normally
[08da53d]	769	findSingleExpression( stmt->orelse.condition, this->indexer );
[8f98b78]	770	stmt->orelse.statement->accept( *visitor );
[1dcd9554]	771	}
	772	}
	773
[b5c5684]	774	template< typename T >
	775	bool isCharType( T t ) {
	776	if ( BasicType * bt = dynamic_cast< BasicType * >( t ) ) {
[71f4e4f]	777	return bt->get_kind() == BasicType::Char \|\| bt->get_kind() == BasicType::SignedChar \|\|
[b5c5684]	778	bt->get_kind() == BasicType::UnsignedChar;
	779	}
	780	return false;
	781	}
	782
[a4ca48c]	783	void Resolver::previsit( SingleInit *singleInit ) {
	784	visit_children = false;
[62423350]	785	// resolve initialization using the possibilities as determined by the currentObject cursor
[0a22cda]	786	Expression * newExpr = new UntypedInitExpr( singleInit->value, currentObject.getOptions() );
[08da53d]	787	findSingleExpression( newExpr, indexer );
[e3e16bc]	788	InitExpr * initExpr = strict_dynamic_cast< InitExpr * >( newExpr );
[62423350]	789
	790	// move cursor to the object that is actually initialized
[e4d829b]	791	currentObject.setNext( initExpr->get_designation() );
[62423350]	792
	793	// discard InitExpr wrapper and retain relevant pieces
[08da53d]	794	newExpr = initExpr->expr;
	795	initExpr->expr = nullptr;
	796	std::swap( initExpr->env, newExpr->env );
[6d6e829]	797	// InitExpr may have inferParams in the case where the expression specializes a function
	798	// pointer, and newExpr may already have inferParams of its own, so a simple swap is not
	799	// sufficient.
[cdb990a]	800	newExpr->spliceInferParams( initExpr );
[e4d829b]	801	delete initExpr;
	802
[6d6e829]	803	// get the actual object's type (may not exactly match what comes back from the resolver
	804	// due to conversions)
[62423350]	805	Type * initContext = currentObject.getCurrentType();
	806
[0a22cda]	807	removeExtraneousCast( newExpr, indexer );
	808
[62423350]	809	// check if actual object's type is char[]
	810	if ( ArrayType * at = dynamic_cast< ArrayType * >( initContext ) ) {
	811	if ( isCharType( at->get_base() ) ) {
	812	// check if the resolved type is char *
	813	if ( PointerType * pt = dynamic_cast< PointerType *>( newExpr->get_result() ) ) {
	814	if ( isCharType( pt->get_base() ) ) {
[0a22cda]	815	if ( CastExpr ce = dynamic_cast< CastExpr >( newExpr ) ) {
[6d6e829]	816	// strip cast if we're initializing a char[] with a char *,
	817	// e.g. char x[] = "hello";
[0a22cda]	818	newExpr = ce->get_arg();
	819	ce->set_arg( nullptr );
	820	std::swap( ce->env, newExpr->env );
	821	delete ce;
	822	}
[62423350]	823	}
	824	}
	825	}
	826	}
[94b4364]	827
[62423350]	828	// set initializer expr to resolved express
[0a22cda]	829	singleInit->value = newExpr;
[62423350]	830
	831	// move cursor to next object in preparation for next initializer
	832	currentObject.increment();
	833	}
[94b4364]	834
[a4ca48c]	835	void Resolver::previsit( ListInit * listInit ) {
	836	visit_children = false;
[62423350]	837	// move cursor into brace-enclosed initializer-list
[e4d829b]	838	currentObject.enterListInit();
[6d6e829]	839	// xxx - fix this so that the list isn't copied, iterator should be used to change current
	840	// element
[e4d829b]	841	std::list<Designation *> newDesignations;
	842	for ( auto p : group_iterate(listInit->get_designations(), listInit->get_initializers()) ) {
[6d6e829]	843	// iterate designations and initializers in pairs, moving the cursor to the current
	844	// designated object and resolving the initializer against that object.
[e4d829b]	845	Designation * des = std::get<0>(p);
	846	Initializer * init = std::get<1>(p);
	847	newDesignations.push_back( currentObject.findNext( des ) );
[a4ca48c]	848	init->accept( *visitor );
[b5c5684]	849	}
[62423350]	850	// set the set of 'resolved' designations and leave the brace-enclosed initializer-list
[e4d829b]	851	listInit->get_designations() = newDesignations; // xxx - memory management
	852	currentObject.exitListInit();
	853
[62423350]	854	// xxx - this part has not be folded into CurrentObject yet
[e4d829b]	855	// } else if ( TypeInstType * tt = dynamic_cast< TypeInstType * >( initContext ) ) {
	856	// Type * base = tt->get_baseType()->get_base();
	857	// if ( base ) {
	858	// // know the implementation type, so try using that as the initContext
	859	// ObjectDecl tmpObj( "", Type::StorageClasses(), LinkageSpec::Cforall, nullptr, base->clone(), nullptr );
	860	// currentObject = &tmpObj;
	861	// visit( listInit );
	862	// } else {
	863	// // missing implementation type -- might be an unknown type variable, so try proceeding with the current init context
	864	// Parent::visit( listInit );
	865	// }
	866	// } else {
[a32b204]	867	}
[71f4e4f]	868
[f1e012b]	869	// ConstructorInit - fall back on C-style initializer
	870	void Resolver::fallbackInit( ConstructorInit * ctorInit ) {
	871	// could not find valid constructor, or found an intrinsic constructor
	872	// fall back on C-style initializer
	873	delete ctorInit->get_ctor();
[6d6e829]	874	ctorInit->set_ctor( nullptr );
[71a145de]	875	delete ctorInit->get_dtor();
[6d6e829]	876	ctorInit->set_dtor( nullptr );
[a4ca48c]	877	maybeAccept( ctorInit->get_init(), *visitor );
[f1e012b]	878	}
	879
[1d2b64f]	880	// needs to be callable from outside the resolver, so this is a standalone function
	881	void resolveCtorInit( ConstructorInit * ctorInit, const SymTab::Indexer & indexer ) {
	882	assert( ctorInit );
[a4ca48c]	883	PassVisitor<Resolver> resolver( indexer );
[1d2b64f]	884	ctorInit->accept( resolver );
	885	}
	886
	887	void resolveStmtExpr( StmtExpr * stmtExpr, const SymTab::Indexer & indexer ) {
	888	assert( stmtExpr );
[a4ca48c]	889	PassVisitor<Resolver> resolver( indexer );
[1d2b64f]	890	stmtExpr->accept( resolver );
[5e2c348]	891	stmtExpr->computeResult();
[dd05e12]	892	// xxx - aggregate the environments from all statements? Possibly in AlternativeFinder instead?
[1d2b64f]	893	}
	894
[a4ca48c]	895	void Resolver::previsit( ConstructorInit *ctorInit ) {
	896	visit_children = false;
[1ba88a0]	897	// xxx - fallback init has been removed => remove fallbackInit function and remove complexity from FixInit and remove C-init from ConstructorInit
[dd05e12]	898	maybeAccept( ctorInit->ctor, *visitor );
	899	maybeAccept( ctorInit->dtor, *visitor );
[071a31a]	900
[5b2f5bb]	901	// found a constructor - can get rid of C-style initializer
[dd05e12]	902	delete ctorInit->init;
	903	ctorInit->init = nullptr;
[ec79847]	904
	905	// intrinsic single parameter constructors and destructors do nothing. Since this was
	906	// implicitly generated, there's no way for it to have side effects, so get rid of it
	907	// to clean up generated code.
[dd05e12]	908	if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->ctor ) ) {
	909	delete ctorInit->ctor;
	910	ctorInit->ctor = nullptr;
[ec79847]	911	}
[f9cebb5]	912
[dd05e12]	913	if ( InitTweak::isIntrinsicSingleArgCallStmt( ctorInit->dtor ) ) {
	914	delete ctorInit->dtor;
	915	ctorInit->dtor = nullptr;
[ec79847]	916	}
[a465caff]	917
	918	// xxx - todo -- what about arrays?
[6d6e829]	919	// if ( dtor == nullptr && InitTweak::isIntrinsicCallStmt( ctorInit->get_ctor() ) ) {
[a465caff]	920	// // can reduce the constructor down to a SingleInit using the
	921	// // second argument from the ctor call, since
	922	// delete ctorInit->get_ctor();
[6d6e829]	923	// ctorInit->set_ctor( nullptr );
[a465caff]	924
	925	// Expression * arg =
	926	// ctorInit->set_init( new SingleInit( arg ) );
	927	// }
[71f4e4f]	928	}
[51b73452]	929	} // namespace ResolvExpr
[a32b204]	930
	931	// Local Variables: //
	932	// tab-width: 4 //
	933	// mode: c++ //
	934	// compile-command: "make install" //
	935	// End: //

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