source: src/InitTweak/RemoveInit.cc@ f326f99

ADT aaron-thesis arm-eh ast-experimental cleanup-dtors ctor deferred_resn demangler enum forall-pointer-decay gc_noraii jacob/cs343-translation jenkins-sandbox memory 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 f326f99 was a5a71d0, checked in by Rob Schluntz <rschlunt@…>, 10 years ago

Merge branch 'fix-memory-error' into ctor

Conflicts:

src/CodeGen/CodeGenerator.cc
src/Makefile.in
src/Parser/DeclarationNode.cc
src/Parser/ParseNode.h
src/Parser/TypeData.cc
src/Parser/parser.cc
src/Parser/parser.yy
src/ResolvExpr/Resolver.cc
src/SymTab/Validate.cc
src/SynTree/Declaration.h
src/SynTree/Mutator.cc
src/SynTree/Mutator.h
src/SynTree/SynTree.h
src/SynTree/Visitor.cc
src/SynTree/Visitor.h
src/libcfa/prelude.cf
  • Property mode set to 100644
File size: 10.6 KB
Line 
1//
2// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
3//
4// The contents of this file are covered under the licence agreement in the
5// file "LICENCE" distributed with Cforall.
6//
7// RemoveInit.cc --
8//
9// Author : Rob Schluntz
10// Created On : Mon May 18 07:44:20 2015
11// Last Modified By : Rob Schluntz
12// Last Modified On : Mon Apr 04 17:18:03 2016
13// Update Count : 166
14//
15
16#include <stack>
17#include <list>
18#include "RemoveInit.h"
19#include "SynTree/Declaration.h"
20#include "SynTree/Type.h"
21#include "SynTree/Expression.h"
22#include "SynTree/Statement.h"
23#include "SynTree/Initializer.h"
24#include "SynTree/Mutator.h"
25#include "SymTab/Autogen.h"
26#include "GenPoly/PolyMutator.h"
27
28namespace InitTweak {
29 namespace {
30 const std::list<Label> noLabels;
31 const std::list<Expression *> noDesignators;
32 }
33
34 class RemoveInit : public GenPoly::PolyMutator {
35 public:
36 /// removes and replaces initialization for polymorphic value objects
37 /// with assignment (TODO: constructor) statements.
38 /// also consistently allocates a temporary variable for the return value
39 /// of a function so that anything which the resolver decides can be assigned
40 /// into the return type of a function can be returned.
41 static void removeInitializers( std::list< Declaration * > &translationUnit );
42
43 RemoveInit();
44 virtual ObjectDecl * mutate( ObjectDecl *objDecl );
45 virtual DeclarationWithType * mutate( FunctionDecl *functionDecl );
46
47 virtual Statement * mutate( ReturnStmt * returnStmt );
48
49 protected:
50 std::list<DeclarationWithType*> returnVals;
51 UniqueName tempNamer;
52 std::string funcName;
53 };
54
55 class CtorDtor : public GenPoly::PolyMutator {
56 public:
57 /// create constructor and destructor statements for object declarations.
58 /// Destructors are inserted directly into the code, whereas constructors
59 /// will be added in after the resolver has run so that the initializer expression
60 /// is only removed if a constructor is found
61 static void generateCtorDtor( std::list< Declaration * > &translationUnit );
62
63 CtorDtor() : inFunction( false ) {}
64
65 virtual ObjectDecl * mutate( ObjectDecl * );
66 virtual DeclarationWithType * mutate( FunctionDecl *functionDecl );
67 virtual Declaration* mutate( StructDecl *aggregateDecl );
68 virtual Declaration* mutate( UnionDecl *aggregateDecl );
69 virtual Declaration* mutate( EnumDecl *aggregateDecl );
70 virtual Declaration* mutate( TraitDecl *aggregateDecl );
71 virtual TypeDecl* mutate( TypeDecl *typeDecl );
72 virtual Declaration* mutate( TypedefDecl *typeDecl );
73
74 protected:
75 bool inFunction;
76 };
77
78 void tweak( std::list< Declaration * > & translationUnit ) {
79 RemoveInit::removeInitializers( translationUnit );
80 CtorDtor::generateCtorDtor( translationUnit );
81 }
82
83 void RemoveInit::removeInitializers( std::list< Declaration * > & translationUnit ) {
84 RemoveInit remover;
85 mutateAll( translationUnit, remover );
86 }
87
88 RemoveInit::RemoveInit() : tempNamer( "_retVal" ) {}
89
90 // in the case where an object has an initializer and a polymorphic type, insert an assignment immediately after the
91 // declaration. This will (seemingly) cause the later phases to do the right thing with the assignment
92 ObjectDecl *RemoveInit::mutate( ObjectDecl *objDecl ) {
93 if (objDecl->get_init() && dynamic_cast<TypeInstType*>(objDecl->get_type())) {
94 if (SingleInit * single = dynamic_cast<SingleInit*>(objDecl->get_init())) {
95 // xxx this can be more complicated - consider ListInit
96 UntypedExpr *assign = new UntypedExpr( new NameExpr( "?{}" ) );
97 assign->get_args().push_back( new AddressExpr (new NameExpr( objDecl->get_name() ) ) );
98 assign->get_args().push_back( single->get_value()->clone() );
99 stmtsToAddAfter.push_back(new ExprStmt(noLabels, assign));
100 } // if
101 } // if
102 return objDecl;
103 }
104
105 Statement *RemoveInit::mutate( ReturnStmt *returnStmt ) {
106 // update for multiple return values
107 assert( returnVals.size() == 0 || returnVals.size() == 1 );
108 // hands off if the function returns an lvalue - we don't want to allocate a temporary if a variable's address
109 // is being returned
110 if ( returnStmt->get_expr() && returnVals.size() == 1 && funcName != "?=?" && ! returnVals.front()->get_type()->get_isLvalue() ) {
111 // ensure return value is not destructed by explicitly creating
112 // an empty SingleInit node wherein maybeConstruct is false
113 ObjectDecl *newObj = new ObjectDecl( tempNamer.newName(), DeclarationNode::NoStorageClass, LinkageSpec::C, 0, returnVals.front()->get_type()->clone(), new ListInit( std::list<Initializer*>(), noDesignators, false ) );
114 stmtsToAdd.push_back( new DeclStmt( noLabels, newObj ) );
115
116 // and explicitly create the constructor expression separately
117 UntypedExpr *construct = new UntypedExpr( new NameExpr( "?{}" ) );
118 construct->get_args().push_back( new AddressExpr (new NameExpr( newObj->get_name() ) ) );
119 construct->get_args().push_back( returnStmt->get_expr() );
120 stmtsToAdd.push_back(new ExprStmt(noLabels, construct));
121
122 returnStmt->set_expr( new VariableExpr( newObj ) );
123 } // if
124 return returnStmt;
125 }
126
127 DeclarationWithType* RemoveInit::mutate( FunctionDecl *functionDecl ) {
128 std::list<DeclarationWithType*> oldReturnVals = returnVals;
129 std::string oldFuncName = funcName;
130
131 FunctionType * type = functionDecl->get_functionType();
132 returnVals = type->get_returnVals();
133 funcName = functionDecl->get_name();
134 DeclarationWithType * decl = Mutator::mutate( functionDecl );
135 returnVals = oldReturnVals;
136 funcName = oldFuncName;
137 return decl;
138 }
139
140
141 void CtorDtor::generateCtorDtor( std::list< Declaration * > & translationUnit ) {
142 CtorDtor ctordtor;
143 mutateAll( translationUnit, ctordtor );
144 }
145
146 namespace {
147 bool tryConstruct( ObjectDecl * objDecl ) {
148 // xxx - handle designations
149 return ! LinkageSpec::isBuiltin( objDecl->get_linkage() ) &&
150 (objDecl->get_init() == NULL ||
151 ( objDecl->get_init() != NULL && objDecl->get_init()->get_maybeConstructed() ));
152 }
153
154 Expression * makeCtorDtorExpr( std::string name, ObjectDecl * objDecl, std::list< Expression * > args ) {
155 UntypedExpr * expr = new UntypedExpr( new NameExpr( name ) );
156 expr->get_args().push_back( new AddressExpr( new VariableExpr( objDecl ) ) );
157 expr->get_args().splice( expr->get_args().end(), args );
158 return expr;
159 }
160
161 class InitExpander : public Visitor {
162 public:
163 InitExpander() {}
164 // ~InitExpander() {}
165 virtual void visit( SingleInit * singleInit );
166 virtual void visit( ListInit * listInit );
167 std::list< Expression * > argList;
168 };
169
170 void InitExpander::visit( SingleInit * singleInit ) {
171 argList.push_back( singleInit->get_value()->clone() );
172 }
173
174 void InitExpander::visit( ListInit * listInit ) {
175 // xxx - for now, assume no nested list inits
176 std::list<Initializer*>::iterator it = listInit->begin_initializers();
177 for ( ; it != listInit->end_initializers(); ++it ) {
178 (*it)->accept( *this );
179 }
180 }
181
182 std::list< Expression * > makeInitList( Initializer * init ) {
183 InitExpander expander;
184 maybeAccept( init, expander );
185 return expander.argList;
186 }
187 }
188
189 ObjectDecl * CtorDtor::mutate( ObjectDecl * objDecl ) {
190 // hands off if designated or if @=
191 if ( tryConstruct( objDecl ) ) {
192 if ( inFunction ) {
193 if ( ArrayType * at = dynamic_cast< ArrayType * >( objDecl->get_type() ) ) {
194 // call into makeArrayFunction from validate.cc to generate calls to ctor/dtor for each element of array
195 // TODO: walk initializer and generate appropriate copy ctor if element has initializer
196 std::list< Statement * > ctor;
197 std::list< Statement * > dtor;
198
199 SymTab::makeArrayFunction( NULL, new VariableExpr( objDecl ), at, "?{}", back_inserter( ctor ) );
200 SymTab::makeArrayFunction( NULL, new VariableExpr( objDecl ), at, "^?{}", front_inserter( dtor ), false );
201
202 // Currently makeArrayFunction produces a single Statement - a CompoundStmt
203 // which wraps everything that needs to happen. As such, it's technically
204 // possible to use a Statement ** in the above calls, but this is inherently
205 // unsafe, so instead we take the slightly less efficient route, but will be
206 // immediately informed if somehow the above assumption is broken. In this case,
207 // we could always wrap the list of statements at this point with a CompoundStmt,
208 // but it seems reasonable at the moment for this to be done by makeArrayFunction
209 // itself
210 assert( ctor.size() == 1 );
211 assert( dtor.size() == 1 );
212
213 objDecl->set_init( new ConstructorInit( ctor.front(), dtor.front(), objDecl->get_init() ) );
214 } else {
215 // it's sufficient to attempt to call the ctor/dtor for the given object and its initializer
216 Expression * ctor = makeCtorDtorExpr( "?{}", objDecl, makeInitList( objDecl->get_init() ) );
217 Expression * dtor = makeCtorDtorExpr( "^?{}", objDecl, std::list< Expression * >() );
218
219 // need to remember init expression, in case no ctors exist
220 // if ctor does exist, want to use ctor expression instead of init
221 // push this decision to the resolver
222 ExprStmt * ctorStmt = new ExprStmt( noLabels, ctor );
223 ExprStmt * dtorStmt = new ExprStmt( noLabels, dtor );
224 objDecl->set_init( new ConstructorInit( ctorStmt, dtorStmt, objDecl->get_init() ) );
225 }
226 } else {
227 // xxx - find a way to construct/destruct globals
228 // hack: implicit "static" initialization routine for each struct type? or something similar?
229 // --ties into module system
230 // this can be done by mangling main and replacing it with our own main which calls each
231 // module initialization routine in some decided order (order given in link command?)
232 // and finally calls mangled main
233 }
234 }
235 return objDecl;
236 }
237
238 DeclarationWithType * CtorDtor::mutate( FunctionDecl *functionDecl ) {
239 // parameters should not be constructed and destructed, so don't mutate FunctionType
240 bool oldInFunc = inFunction;
241 mutateAll( functionDecl->get_oldDecls(), *this );
242 inFunction = true;
243 functionDecl->set_statements( maybeMutate( functionDecl->get_statements(), *this ) );
244 inFunction = oldInFunc;
245 return functionDecl;
246 }
247
248 // should not traverse into any of these declarations to find objects
249 // that need to be constructed or destructed
250 Declaration* CtorDtor::mutate( StructDecl *aggregateDecl ) { return aggregateDecl; }
251 Declaration* CtorDtor::mutate( UnionDecl *aggregateDecl ) { return aggregateDecl; }
252 Declaration* CtorDtor::mutate( EnumDecl *aggregateDecl ) { return aggregateDecl; }
253 Declaration* CtorDtor::mutate( TraitDecl *aggregateDecl ) { return aggregateDecl; }
254 TypeDecl* CtorDtor::mutate( TypeDecl *typeDecl ) { return typeDecl; }
255 Declaration* CtorDtor::mutate( TypedefDecl *typeDecl ) { return typeDecl; }
256
257} // namespace InitTweak
258
259// Local Variables: //
260// tab-width: 4 //
261// mode: c++ //
262// compile-command: "make install" //
263// End: //
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