view src/share/vm/ci/ciSignature.cpp @ 9126:bc26f978b0ce

HotSpotResolvedObjectType: implement hasFinalizeSubclass() correctly don't use the (wrong) cached value, but ask the runtime on each request. Fixes regression on xml.* benchmarks @ specjvm2008. The problem was: After the constructor of Object was deoptimized due to an assumption violation, it was recompiled again after some time. However, on recompilation, the value of hasFinalizeSubclass for the class was not updated and it was compiled again with a, now wrong, assumption, which then triggers deoptimization again. This was repeated until it hit the recompilation limit (defined by PerMethodRecompilationCutoff), and therefore only executed by the interpreter from now on, causing the performance regression.
author Bernhard Urban <bernhard.urban@jku.at>
date Mon, 15 Apr 2013 19:54:58 +0200
parents f6b0eb4e44cf
children 78bbf4d43a14
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/*
 * Copyright (c) 1999, 2011, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 *
 */

#include "precompiled.hpp"
#include "ci/ciMethodType.hpp"
#include "ci/ciSignature.hpp"
#include "ci/ciUtilities.hpp"
#include "memory/allocation.inline.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/signature.hpp"

// ciSignature
//
// This class represents the signature of a method.

// ------------------------------------------------------------------
// ciSignature::ciSignature
ciSignature::ciSignature(ciKlass* accessing_klass, constantPoolHandle cpool, ciSymbol* symbol) {
  ASSERT_IN_VM;
  EXCEPTION_CONTEXT;
  _accessing_klass = accessing_klass;
  _symbol = symbol;

  ciEnv* env = CURRENT_ENV;
  Arena* arena = env->arena();
  _types = new (arena) GrowableArray<ciType*>(arena, 8, 0, NULL);

  int size = 0;
  int count = 0;
  ResourceMark rm(THREAD);
  Symbol* sh = symbol->get_symbol();
  SignatureStream ss(sh);
  for (; ; ss.next()) {
    // Process one element of the signature
    ciType* type;
    if (!ss.is_object()) {
      type = ciType::make(ss.type());
    } else {
      Symbol* name = ss.as_symbol(THREAD);
      if (HAS_PENDING_EXCEPTION) {
        type = ss.is_array() ? (ciType*)ciEnv::unloaded_ciobjarrayklass()
          : (ciType*)ciEnv::unloaded_ciinstance_klass();
        env->record_out_of_memory_failure();
        CLEAR_PENDING_EXCEPTION;
      } else {
        ciSymbol* klass_name = env->get_symbol(name);
        type = env->get_klass_by_name_impl(_accessing_klass, cpool, klass_name, false);
      }
    }
    _types->append(type);
    if (ss.at_return_type()) {
      // Done processing the return type; do not add it into the count.
      break;
    }
    size += type->size();
    count++;
  }
  _size = size;
  _count = count;
}

// ------------------------------------------------------------------
// ciSignature::ciSignature
ciSignature::ciSignature(ciKlass* accessing_klass, ciSymbol* symbol, ciMethodType* method_type) :
  _symbol(symbol),
  _accessing_klass(accessing_klass),
  _size( method_type->ptype_slot_count()),
  _count(method_type->ptype_count())
{
  ASSERT_IN_VM;
  EXCEPTION_CONTEXT;
  Arena* arena = CURRENT_ENV->arena();
  _types = new (arena) GrowableArray<ciType*>(arena, _count + 1, 0, NULL);
  for (int i = 0; i < _count; i++) {
    _types->append(method_type->ptype_at(i));
  }
  _types->append(method_type->rtype());
}

// ------------------------------------------------------------------
// ciSignature::return_type
//
// What is the return type of this signature?
ciType* ciSignature::return_type() const {
  return _types->at(_count);
}

// ------------------------------------------------------------------
// ciSignature::type_at
//
// What is the type of the index'th element of this
// signature?
ciType* ciSignature::type_at(int index) const {
  assert(index < _count, "out of bounds");
  // The first _klasses element holds the return klass.
  return _types->at(index);
}

// ------------------------------------------------------------------
// ciSignature::equals
//
// Compare this signature to another one.  Signatures with different
// accessing classes but with signature-types resolved to the same
// types are defined to be equal.
bool ciSignature::equals(ciSignature* that) {
  // Compare signature
  if (!this->as_symbol()->equals(that->as_symbol()))  return false;
  // Compare all types of the arguments
  for (int i = 0; i < _count; i++) {
    if (this->type_at(i) != that->type_at(i))         return false;
  }
  // Compare the return type
  if (this->return_type() != that->return_type())     return false;
  return true;
}

// ------------------------------------------------------------------
// ciSignature::print_signature
void ciSignature::print_signature() {
  _symbol->print_symbol();
}

// ------------------------------------------------------------------
// ciSignature::print
void ciSignature::print() {
  tty->print("<ciSignature symbol=");
  print_signature();
 tty->print(" accessing_klass=");
  _accessing_klass->print();
  tty->print(" address=0x%x>", (address)this);
}