view src/share/vm/classfile/verificationType.cpp @ 1091:6aa7255741f3

6906727: UseCompressedOops: some card-marking fixes related to object arrays Summary: Introduced a new write_ref_array(HeapWords* start, size_t count) method that does the requisite MemRegion range calculation so (some of the) clients of the erstwhile write_ref_array(MemRegion mr) do not need to worry. This removed all external uses of array_size(), which was also simplified and made private. Asserts were added to catch other possible issues. Further, less essential, fixes stemming from this investigation are deferred to CR 6904516 (to follow shortly in hs17). Reviewed-by: kvn, coleenp, jmasa
author ysr
date Thu, 03 Dec 2009 15:01:57 -0800
parents a61af66fc99e
children c18cbe5936b8
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/*
 * Copyright 2003-2006 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/_verificationType.cpp.incl"

VerificationType VerificationType::from_tag(u1 tag) {
  switch (tag) {
    case ITEM_Top:     return bogus_type();
    case ITEM_Integer: return integer_type();
    case ITEM_Float:   return float_type();
    case ITEM_Double:  return double_type();
    case ITEM_Long:    return long_type();
    case ITEM_Null:    return null_type();
    default:
      ShouldNotReachHere();
      return bogus_type();
  }
}

bool VerificationType::is_reference_assignable_from(
    const VerificationType& from, instanceKlassHandle context, TRAPS) const {
  if (from.is_null()) {
    // null is assignable to any reference
    return true;
  } else if (is_null()) {
    return false;
  } else if (name() == from.name()) {
    return true;
  } else if (is_object()) {
    // We need check the class hierarchy to check assignability
    if (name() == vmSymbols::java_lang_Object()) {
      // any object or array is assignable to java.lang.Object
      return true;
    }
    klassOop this_class = SystemDictionary::resolve_or_fail(
        name_handle(), Handle(THREAD, context->class_loader()),
        Handle(THREAD, context->protection_domain()), true, CHECK_false);
    if (this_class->klass_part()->is_interface()) {
      // We treat interfaces as java.lang.Object, including
      // java.lang.Cloneable and java.io.Serializable
      return true;
    } else if (from.is_object()) {
      klassOop from_class = SystemDictionary::resolve_or_fail(
          from.name_handle(), Handle(THREAD, context->class_loader()),
          Handle(THREAD, context->protection_domain()), true, CHECK_false);
      return instanceKlass::cast(from_class)->is_subclass_of(this_class);
    }
  } else if (is_array() && from.is_array()) {
    VerificationType comp_this = get_component(CHECK_false);
    VerificationType comp_from = from.get_component(CHECK_false);
    return comp_this.is_assignable_from(comp_from, context, CHECK_false);
  }
  return false;
}

VerificationType VerificationType::get_component(TRAPS) const {
  assert(is_array() && name()->utf8_length() >= 2, "Must be a valid array");
  symbolOop component;
  switch (name()->byte_at(1)) {
    case 'Z': return VerificationType(Boolean);
    case 'B': return VerificationType(Byte);
    case 'C': return VerificationType(Char);
    case 'S': return VerificationType(Short);
    case 'I': return VerificationType(Integer);
    case 'J': return VerificationType(Long);
    case 'F': return VerificationType(Float);
    case 'D': return VerificationType(Double);
    case '[':
      component = SymbolTable::lookup(
        name(), 1, name()->utf8_length(),
        CHECK_(VerificationType::bogus_type()));
      return VerificationType::reference_type(component);
    case 'L':
      component = SymbolTable::lookup(
        name(), 2, name()->utf8_length() - 1,
        CHECK_(VerificationType::bogus_type()));
      return VerificationType::reference_type(component);
    default:
      ShouldNotReachHere();
      return VerificationType::bogus_type();
  }
}

#ifndef PRODUCT

void VerificationType::print_on(outputStream* st) const {
  switch (_u._data) {
    case Bogus:            st->print(" bogus "); break;
    case Category1:        st->print(" category1 "); break;
    case Category2:        st->print(" category2 "); break;
    case Category2_2nd:    st->print(" category2_2nd "); break;
    case Boolean:          st->print(" boolean "); break;
    case Byte:             st->print(" byte "); break;
    case Short:            st->print(" short "); break;
    case Char:             st->print(" char "); break;
    case Integer:          st->print(" integer "); break;
    case Float:            st->print(" float "); break;
    case Long:             st->print(" long "); break;
    case Double:           st->print(" double "); break;
    case Long_2nd:         st->print(" long_2nd "); break;
    case Double_2nd:       st->print(" double_2nd "); break;
    case Null:             st->print(" null "); break;
    default:
      if (is_uninitialized_this()) {
        st->print(" uninitializedThis ");
      } else if (is_uninitialized()) {
        st->print(" uninitialized %d ", bci());
      } else {
        st->print(" class %s ", name()->as_klass_external_name());
      }
  }
}

#endif