Mercurial > projects > ldc
view dmd/clone.c @ 1317:4099548c80e0
Allocate objects on the stack if they (a) don't have a destructor, and
(b) don't override the delete operator (on top of the regular conditions for
stack allocation that also apply to arrays, structs, etc.).
The "no destructor" clause is not strictly necessary, but calling them at the
right time would be tricky to say the least; it would involve, among other
things, "manually" inserting a try-finally block around anything that might
throw exceptions not caught in the current function.
Note: objects with custom new operators are automatically ignored because they
don't use the regular allocation runtime call, so there's no need to pay special
attention to them.
author | Frits van Bommel <fvbommel wxs.nl> |
---|---|
date | Sat, 09 May 2009 00:50:15 +0200 |
parents | aaade6ded589 |
children |
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// Compiler implementation of the D programming language // Copyright (c) 1999-2008 by Digital Mars // All Rights Reserved // written by Walter Bright // http://www.digitalmars.com // License for redistribution is by either the Artistic License // in artistic.txt, or the GNU General Public License in gnu.txt. // See the included readme.txt for details. #include <stdio.h> #include <assert.h> #include "root.h" #include "aggregate.h" #include "scope.h" #include "mtype.h" #include "declaration.h" #include "module.h" #include "id.h" #include "expression.h" #include "statement.h" /********************************* * Generate expression that calls opClone() * for each member of the struct * (can be NULL for members that don't need one) */ #if DMDV2 Expression *StructDeclaration::cloneMembers() { Expression *e = NULL; for (size_t i = 0; i < fields.dim; i++) { Dsymbol *s = (Dsymbol *)fields.data[i]; VarDeclaration *v = s->isVarDeclaration(); assert(v && v->storage_class & STCfield); Type *tv = v->type->toBasetype(); size_t dim = 1; while (tv->ty == Tsarray) { TypeSArray *ta = (TypeSArray *)tv; dim *= ((TypeSArray *)tv)->dim->toInteger(); tv = tv->nextOf()->toBasetype(); } if (tv->ty == Tstruct) { TypeStruct *ts = (TypeStruct *)tv; StructDeclaration *sd = ts->sym; if (sd->opclone) { Expression *ex; // this.v ex = new ThisExp(0); ex = new DotVarExp(0, ex, v, 0); if (dim == 1) { // this.v.opClone() ex = new DotVarExp(0, ex, sd->opclone, 0); ex = new CallExp(0, ex); } else { // _callOpClones(&this.v, opclone, dim) Expressions *args = new Expressions(); args->push(new AddrExp(0, ex)); args->push(new SymOffExp(0, sd->opclone, 0)); args->push(new IntegerExp(dim)); FuncDeclaration *ec = FuncDeclaration::genCfunc(Type::tvoid, "_callOpClones"); ex = new CallExp(0, new VarExp(0, ec), args); } e = Expression::combine(e, ex); } } } return e; } #endif /***************************************** * Create inclusive destructor for struct by aggregating * all the destructors in dtors[] with the destructors for * all the members. */ FuncDeclaration *AggregateDeclaration::buildDtor(Scope *sc) { //printf("StructDeclaration::buildDtor() %s\n", toChars()); Expression *e = NULL; #if DMDV2 for (size_t i = 0; i < fields.dim; i++) { Dsymbol *s = (Dsymbol *)fields.data[i]; VarDeclaration *v = s->isVarDeclaration(); assert(v && v->storage_class & STCfield); Type *tv = v->type->toBasetype(); size_t dim = 1; while (tv->ty == Tsarray) { TypeSArray *ta = (TypeSArray *)tv; dim *= ((TypeSArray *)tv)->dim->toInteger(); tv = tv->nextOf()->toBasetype(); } if (tv->ty == Tstruct) { TypeStruct *ts = (TypeStruct *)tv; StructDeclaration *sd = ts->sym; if (sd->dtor) { Expression *ex; // this.v ex = new ThisExp(0); ex = new DotVarExp(0, ex, v, 0); if (dim == 1) { // this.v.dtor() ex = new DotVarExp(0, ex, sd->dtor, 0); ex = new CallExp(0, ex); } else { // Typeinfo.destroy(cast(void*)&this.v); Expression *ea = new AddrExp(0, ex); ea = new CastExp(0, ea, Type::tvoid->pointerTo()); Expressions *args = new Expressions(); args->push(ea); Expression *et = v->type->getTypeInfo(sc); et = new DotIdExp(0, et, Id::destroy); ex = new CallExp(0, et, args); } e = Expression::combine(ex, e); // combine in reverse order } } } /* Build our own "destructor" which executes e */ if (e) { //printf("Building __fieldDtor()\n"); DtorDeclaration *dd = new DtorDeclaration(0, 0, Lexer::idPool("__fieldDtor")); dd->fbody = new ExpStatement(0, e); dtors.shift(dd); members->push(dd); dd->semantic(sc); } #endif switch (dtors.dim) { case 0: return NULL; case 1: return (FuncDeclaration *)dtors.data[0]; default: e = NULL; for (size_t i = 0; i < dtors.dim; i++) { FuncDeclaration *fd = (FuncDeclaration *)dtors.data[i]; Expression *ex = new ThisExp(0); ex = new DotVarExp(0, ex, fd); ex = new CallExp(0, ex); e = Expression::combine(ex, e); } DtorDeclaration *dd = new DtorDeclaration(0, 0, Lexer::idPool("__aggrDtor")); dd->fbody = new ExpStatement(0, e); members->push(dd); dd->semantic(sc); return dd; } }