view src/share/vm/code/debugInfo.cpp @ 20543:e7d0505c8a30

8059758: Footprint regressions with JDK-8038423 Summary: Changes in JDK-8038423 always initialize (zero out) virtual memory used for auxiliary data structures. This causes a footprint regression for G1 in startup benchmarks. This is because they do not touch that memory at all, so the operating system does not actually commit these pages. The fix is to, if the initialization value of the data structures matches the default value of just committed memory (=0), do not do anything. Reviewed-by: jwilhelm, brutisso
author tschatzl
date Fri, 10 Oct 2014 15:51:58 +0200
parents 78bbf4d43a14
children 52b4284cb496
line wrap: on
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/*
 * Copyright (c) 1997, 2014, 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 "code/debugInfo.hpp"
#include "code/debugInfoRec.hpp"
#include "code/nmethod.hpp"
#include "runtime/handles.inline.hpp"

PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC

// Constructors

DebugInfoWriteStream::DebugInfoWriteStream(DebugInformationRecorder* recorder, int initial_size)
: CompressedWriteStream(initial_size) {
  _recorder = recorder;
}

// Serializing oops

void DebugInfoWriteStream::write_handle(jobject h) {
  write_int(recorder()->oop_recorder()->find_index(h));
}

void DebugInfoWriteStream::write_metadata(Metadata* h) {
  write_int(recorder()->oop_recorder()->find_index(h));
}

ScopeValue* DebugInfoReadStream::read_object_value() {
  int id = read_int();
#ifdef ASSERT
  assert(_obj_pool != NULL, "object pool does not exist");
  for (int i = _obj_pool->length() - 1; i >= 0; i--) {
    assert(((ObjectValue*) _obj_pool->at(i))->id() != id, "should not be read twice");
  }
#endif
  ObjectValue* result = new ObjectValue(id);
  // Cache the object since an object field could reference it.
  _obj_pool->push(result);
  result->read_object(this);
  return result;
}

ScopeValue* DebugInfoReadStream::get_cached_object() {
  int id = read_int();
  assert(_obj_pool != NULL, "object pool does not exist");
  for (int i = _obj_pool->length() - 1; i >= 0; i--) {
    ObjectValue* ov = (ObjectValue*) _obj_pool->at(i);
    if (ov->id() == id) {
      return ov;
    }
  }
  ShouldNotReachHere();
  return NULL;
}

// Serializing scope values

enum { LOCATION_CODE = 0, CONSTANT_INT_CODE = 1,  CONSTANT_OOP_CODE = 2,
                          CONSTANT_LONG_CODE = 3, CONSTANT_DOUBLE_CODE = 4,
                          OBJECT_CODE = 5,        OBJECT_ID_CODE = 6 };

ScopeValue* ScopeValue::read_from(DebugInfoReadStream* stream) {
  ScopeValue* result = NULL;
  switch(stream->read_int()) {
   case LOCATION_CODE:        result = new LocationValue(stream);        break;
   case CONSTANT_INT_CODE:    result = new ConstantIntValue(stream);     break;
   case CONSTANT_OOP_CODE:    result = new ConstantOopReadValue(stream); break;
   case CONSTANT_LONG_CODE:   result = new ConstantLongValue(stream);    break;
   case CONSTANT_DOUBLE_CODE: result = new ConstantDoubleValue(stream);  break;
   case OBJECT_CODE:          result = stream->read_object_value();      break;
   case OBJECT_ID_CODE:       result = stream->get_cached_object();      break;
   default: ShouldNotReachHere();
  }
  return result;
}

// LocationValue

LocationValue::LocationValue(DebugInfoReadStream* stream) {
  _location = Location(stream);
}

void LocationValue::write_on(DebugInfoWriteStream* stream) {
  stream->write_int(LOCATION_CODE);
  location().write_on(stream);
}

void LocationValue::print_on(outputStream* st) const {
  location().print_on(st);
}

// ObjectValue

void ObjectValue::read_object(DebugInfoReadStream* stream) {
  _klass = read_from(stream);
  assert(_klass->is_constant_oop(), "should be constant java mirror oop");
  int length = stream->read_int();
  for (int i = 0; i < length; i++) {
    ScopeValue* val = read_from(stream);
    _field_values.append(val);
  }
}

void ObjectValue::write_on(DebugInfoWriteStream* stream) {
  if (_visited) {
    stream->write_int(OBJECT_ID_CODE);
    stream->write_int(_id);
  } else {
    _visited = true;
    stream->write_int(OBJECT_CODE);
    stream->write_int(_id);
    _klass->write_on(stream);
    int length = _field_values.length();
    stream->write_int(length);
    for (int i = 0; i < length; i++) {
      _field_values.at(i)->write_on(stream);
    }
  }
}

void ObjectValue::print_on(outputStream* st) const {
  st->print("obj[%d]", _id);
}

void ObjectValue::print_fields_on(outputStream* st) const {
#ifndef PRODUCT
  if (_field_values.length() > 0) {
    _field_values.at(0)->print_on(st);
  }
  for (int i = 1; i < _field_values.length(); i++) {
    st->print(", ");
    _field_values.at(i)->print_on(st);
  }
#endif
}

// ConstantIntValue

ConstantIntValue::ConstantIntValue(DebugInfoReadStream* stream) {
  _value = stream->read_signed_int();
}

void ConstantIntValue::write_on(DebugInfoWriteStream* stream) {
  stream->write_int(CONSTANT_INT_CODE);
  stream->write_signed_int(value());
}

void ConstantIntValue::print_on(outputStream* st) const {
  st->print("%d", value());
}

// ConstantLongValue

ConstantLongValue::ConstantLongValue(DebugInfoReadStream* stream) {
  _value = stream->read_long();
}

void ConstantLongValue::write_on(DebugInfoWriteStream* stream) {
  stream->write_int(CONSTANT_LONG_CODE);
  stream->write_long(value());
}

void ConstantLongValue::print_on(outputStream* st) const {
  st->print(INT64_FORMAT, value());
}

// ConstantDoubleValue

ConstantDoubleValue::ConstantDoubleValue(DebugInfoReadStream* stream) {
  _value = stream->read_double();
}

void ConstantDoubleValue::write_on(DebugInfoWriteStream* stream) {
  stream->write_int(CONSTANT_DOUBLE_CODE);
  stream->write_double(value());
}

void ConstantDoubleValue::print_on(outputStream* st) const {
  st->print("%f", value());
}

// ConstantOopWriteValue

void ConstantOopWriteValue::write_on(DebugInfoWriteStream* stream) {
  assert(JNIHandles::resolve(value()) == NULL ||
         Universe::heap()->is_in_reserved(JNIHandles::resolve(value())),
         "Should be in heap");
  stream->write_int(CONSTANT_OOP_CODE);
  stream->write_handle(value());
}

void ConstantOopWriteValue::print_on(outputStream* st) const {
  JNIHandles::resolve(value())->print_value_on(st);
}


// ConstantOopReadValue

ConstantOopReadValue::ConstantOopReadValue(DebugInfoReadStream* stream) {
  _value = Handle(stream->read_oop());
  assert(_value() == NULL ||
         Universe::heap()->is_in_reserved(_value()), "Should be in heap");
}

void ConstantOopReadValue::write_on(DebugInfoWriteStream* stream) {
  ShouldNotReachHere();
}

void ConstantOopReadValue::print_on(outputStream* st) const {
  value()()->print_value_on(st);
}


// MonitorValue

MonitorValue::MonitorValue(ScopeValue* owner, Location basic_lock, bool eliminated) {
  _owner       = owner;
  _basic_lock  = basic_lock;
  _eliminated  = eliminated;
}

MonitorValue::MonitorValue(DebugInfoReadStream* stream) {
  _basic_lock  = Location(stream);
  _owner       = ScopeValue::read_from(stream);
  _eliminated  = (stream->read_bool() != 0);
}

void MonitorValue::write_on(DebugInfoWriteStream* stream) {
  _basic_lock.write_on(stream);
  _owner->write_on(stream);
  stream->write_bool(_eliminated);
}

#ifndef PRODUCT
void MonitorValue::print_on(outputStream* st) const {
  st->print("monitor{");
  owner()->print_on(st);
  st->print(",");
  basic_lock().print_on(st);
  st->print("}");
  if (_eliminated) {
    st->print(" (eliminated)");
  }
}
#endif