Changeset a28bc02 for src/InitTweak

Timestamp:

May 11, 2017, 2:09:51 PM (8 years ago)

Author:

Rob Schluntz <rschlunt@…>

Branches:

ADT, aaron-thesis, arm-eh, ast-experimental, cleanup-dtors, deferred_resn, demangler, enum, forall-pointer-decay, jacob/cs343-translation, jenkins-sandbox, master, new-ast, new-ast-unique-expr, new-env, no_list, persistent-indexer, pthread-emulation, qualifiedEnum, resolv-new, with_gc

Children:

6a4f3d4

Parents:

ddbde34

Message:

assignment argument and return value are now always copy constructed

Location:

src/InitTweak

Files:

• FixInit.cc (modified) (5 diffs)
• GenInit.cc (modified) (1 diff)

src/InitTweak/FixInit.cc ¶

@@ -361 +361 @@
                                         FunctionType * ftype = dynamic_cast< FunctionType * >( GenPoly::getFunctionType( funcDecl->get_type() ) );
                                         assert( ftype );
-                                        if ( (isConstructor( funcDecl->get_name() ) || funcDecl->get_name() == "?=?") && ftype->get_parameters().size() == 2 ) {
+                                        if ( isConstructor( funcDecl->get_name() ) && ftype->get_parameters().size() == 2 ) {
                                                 Type * t1 = ftype->get_parameters().front()->get_type();
                                                 Type * t2 = ftype->get_parameters().back()->get_type();
@@ -367 +367 @@
 
                                                 if ( ResolvExpr::typesCompatible( ptrType->get_base(), t2, SymTab::Indexer() ) ) {
-                                                        // optimization: don't need to copy construct in order to call a copy constructor or
-                                                        // assignment operator
+                                                        // optimization: don't need to copy construct in order to call a copy constructor
                                                         return appExpr;
                                                 } // if
@@ -636 +635 @@
                                 assert( ! stmtExpr->get_returnDecls().empty() );
                                 body->get_kids().push_back( new ExprStmt( noLabels, new VariableExpr( stmtExpr->get_returnDecls().front() ) ) );
-                        }
-                        stmtExpr->get_returnDecls().clear();
-                        stmtExpr->get_dtors().clear();
+                                stmtExpr->get_returnDecls().clear();
+                                stmtExpr->get_dtors().clear();
+                        }
+                        assert( stmtExpr->get_returnDecls().empty() );
+                        assert( stmtExpr->get_dtors().empty() );
                         return stmtExpr;
                 }
@@ -667 +668 @@
                         stmtsToAdd.splice( stmtsToAdd.end(), fixer.stmtsToAdd );
                         unqMap[unqExpr->get_id()] = unqExpr;
+                        if ( unqCount[ unqExpr->get_id() ] == 0 ) {  // insert destructor after the last use of the unique expression
+                                stmtsToAdd.splice( stmtsToAddAfter.end(), dtors[ unqExpr->get_id() ] );
+                        } else { // remember dtors for last instance of unique expr
+                                dtors[ unqExpr->get_id() ] = fixer.stmtsToAddAfter;
+                        }
                         if ( UntypedExpr * deref = dynamic_cast< UntypedExpr * >( unqExpr->get_expr() ) ) {
                                 // unique expression is now a dereference, because the inner expression is an lvalue returning function call.
@@ -675 +681 @@
                                 getCallArg( deref, 0 ) = unqExpr;
                                 addDeref.insert( unqExpr->get_id() );
-                                if ( unqCount[ unqExpr->get_id() ] == 0 ) {  // insert destructor after the last use of the unique expression
-                                        stmtsToAdd.splice( stmtsToAddAfter.end(), dtors[ unqExpr->get_id() ] );
-                                } else { // remember dtors for last instance of unique expr
-                                        dtors[ unqExpr->get_id() ] = fixer.stmtsToAddAfter;
-                                }
                                 return deref;
                         }

src/InitTweak/GenInit.cc ¶

@@ -142 +142 @@
                 // hands off if the function returns an lvalue - we don't want to allocate a temporary if a variable's address
                 // is being returned
-                // Note: under the assumption that assignments return *this, checking for ?=? here is an optimization, since it shouldn't be necessary to copy construct `this`. This is a temporary optimization until reference types are added, at which point this should be removed, along with the analogous optimization in copy constructor generation.
-                if ( returnStmt->get_expr() && returnVals.size() == 1 && funcName != "?=?" && ! returnVals.front()->get_type()->get_lvalue() ) {
+                if ( returnStmt->get_expr() && returnVals.size() == 1 && ! returnVals.front()->get_type()->get_lvalue() ) {
                         // explicitly construct the return value using the return expression and the retVal object
                         assertf( returnVals.front()->get_name() != "", "Function %s has unnamed return value\n", funcName.c_str() );