diff -r 000000000000 -r a61af66fc99e src/share/vm/ci/ciObject.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/ci/ciObject.cpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,215 @@ +/* + * Copyright 1999-2007 Sun Microsystems, Inc. All Rights Reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +#include "incls/_precompiled.incl" +#include "incls/_ciObject.cpp.incl" + +// ciObject +// +// This class represents an oop in the HotSpot virtual machine. +// Its subclasses are structured in a hierarchy which mirrors +// an aggregate of the VM's oop and klass hierarchies (see +// oopHierarchy.hpp). Each instance of ciObject holds a handle +// to a corresponding oop on the VM side and provides routines +// for accessing the information in its oop. By using the ciObject +// hierarchy for accessing oops in the VM, the compiler ensures +// that it is safe with respect to garbage collection; that is, +// GC and compilation can proceed independently without +// interference. +// +// Within the VM, the oop and klass hierarchies are separate. +// The compiler interface does not preserve this separation -- +// the distinction between `klassOop' and `Klass' are not +// reflected in the interface and instead the Klass hierarchy +// is directly modeled as the subclasses of ciKlass. + +// ------------------------------------------------------------------ +// ciObject::ciObject +ciObject::ciObject(oop o) { + ASSERT_IN_VM; + if (ciObjectFactory::is_initialized()) { + _handle = JNIHandles::make_local(o); + } else { + _handle = JNIHandles::make_global(o); + } + _klass = NULL; + _ident = 0; +} + +// ------------------------------------------------------------------ +// ciObject::ciObject +// +ciObject::ciObject(Handle h) { + ASSERT_IN_VM; + if (ciObjectFactory::is_initialized()) { + _handle = JNIHandles::make_local(h()); + } else { + _handle = JNIHandles::make_global(h); + } + _klass = NULL; + _ident = 0; +} + +// ------------------------------------------------------------------ +// ciObject::ciObject +// +// Unloaded klass/method variant. `klass' is the klass of the unloaded +// klass/method, if that makes sense. +ciObject::ciObject(ciKlass* klass) { + ASSERT_IN_VM; + assert(klass != NULL, "must supply klass"); + _handle = NULL; + _klass = klass; + _ident = 0; +} + +// ------------------------------------------------------------------ +// ciObject::ciObject +// +// NULL variant. Used only by ciNullObject. +ciObject::ciObject() { + ASSERT_IN_VM; + _handle = NULL; + _klass = NULL; + _ident = 0; +} + +// ------------------------------------------------------------------ +// ciObject::klass +// +// Get the ciKlass of this ciObject. +ciKlass* ciObject::klass() { + if (_klass == NULL) { + if (_handle == NULL) { + // When both _klass and _handle are NULL, we are dealing + // with the distinguished instance of ciNullObject. + // No one should ask it for its klass. + assert(is_null_object(), "must be null object"); + ShouldNotReachHere(); + return NULL; + } + + GUARDED_VM_ENTRY( + oop o = get_oop(); + _klass = CURRENT_ENV->get_object(o->klass())->as_klass(); + ); + } + return _klass; +} + +// ------------------------------------------------------------------ +// ciObject::set_ident +// +// Set the unique identity number of a ciObject. +void ciObject::set_ident(uint id) { + assert((_ident >> FLAG_BITS) == 0, "must only initialize once"); + assert( id < ((uint)1 << (BitsPerInt-FLAG_BITS)), "id too big"); + _ident = _ident + (id << FLAG_BITS); +} + +// ------------------------------------------------------------------ +// ciObject::ident +// +// Report the unique identity number of a ciObject. +uint ciObject::ident() { + uint id = _ident >> FLAG_BITS; + assert(id != 0, "must be initialized"); + return id; +} + +// ------------------------------------------------------------------ +// ciObject::equals +// +// Are two ciObjects equal? +bool ciObject::equals(ciObject* obj) { + return (this == obj); +} + +// ------------------------------------------------------------------ +// ciObject::hash +// +// A hash value for the convenience of compilers. +// +// Implementation note: we use the address of the ciObject as the +// basis for the hash. Use the _ident field, which is well-behaved. +int ciObject::hash() { + return ident() * 31; +} + +// ------------------------------------------------------------------ +// ciObject::encoding +// +// The address which the compiler should embed into the +// generated code to represent this oop. This address +// is not the true address of the oop -- it will get patched +// during nmethod creation. +// +// +// +// Implementation note: we use the handle as the encoding. The +// nmethod constructor resolves the handle and patches in the oop. +// +// This method should be changed to return an generified address +// to discourage use of the JNI handle. +jobject ciObject::encoding() { + assert(is_null_object() || handle() != NULL, "cannot embed null pointer"); + assert(has_encoding(), "oop must be NULL or perm"); + return handle(); +} + +// ------------------------------------------------------------------ +// ciObject::has_encoding +bool ciObject::has_encoding() { + return handle() == NULL || is_perm(); +} + + +// ------------------------------------------------------------------ +// ciObject::print +// +// Print debugging output about this ciObject. +// +// Implementation note: dispatch to the virtual print_impl behavior +// for this ciObject. +void ciObject::print(outputStream* st) { + st->print("<%s", type_string()); + GUARDED_VM_ENTRY(print_impl(st);) + st->print(" ident=%d %s address=0x%x>", ident(), + is_perm() ? "PERM" : "", + (address)this); +} + +// ------------------------------------------------------------------ +// ciObject::print_oop +// +// Print debugging output about the oop this ciObject represents. +void ciObject::print_oop(outputStream* st) { + if (is_null_object()) { + st->print_cr("NULL"); + } else if (!is_loaded()) { + st->print_cr("UNLOADED"); + } else { + GUARDED_VM_ENTRY(get_oop()->print_on(st);) + } +}