view src/share/vm/oops/constMethodOop.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
line wrap: on
line source

/*
 * 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/_constMethodOop.cpp.incl"

// Static initialization
const u2 constMethodOopDesc::MAX_IDNUM   = 0xFFFE;
const u2 constMethodOopDesc::UNSET_IDNUM = 0xFFFF;

// How big must this constMethodObject be?

int constMethodOopDesc::object_size(int code_size,
                                    int compressed_line_number_size,
                                    int local_variable_table_length,
                                    int checked_exceptions_length) {
  int extra_bytes = code_size;
  if (compressed_line_number_size > 0) {
    extra_bytes += compressed_line_number_size;
  }
  if (checked_exceptions_length > 0) {
    extra_bytes += sizeof(u2);
    extra_bytes += checked_exceptions_length * sizeof(CheckedExceptionElement);
  }
  if (local_variable_table_length > 0) {
    extra_bytes += sizeof(u2);
    extra_bytes +=
              local_variable_table_length * sizeof(LocalVariableTableElement);
  }
  int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
  return align_object_size(header_size() + extra_words);
}


// linenumber table - note that length is unknown until decompression,
// see class CompressedLineNumberReadStream.

u_char* constMethodOopDesc::compressed_linenumber_table() const {
  // Located immediately following the bytecodes.
  assert(has_linenumber_table(), "called only if table is present");
  return code_end();
}

u2* constMethodOopDesc::checked_exceptions_length_addr() const {
  // Located at the end of the constMethod.
  assert(has_checked_exceptions(), "called only if table is present");
  return last_u2_element();
}

u2* constMethodOopDesc::localvariable_table_length_addr() const {
  assert(has_localvariable_table(), "called only if table is present");
  if (has_checked_exceptions()) {
    // If checked_exception present, locate immediately before them.
    return (u2*) checked_exceptions_start() - 1;
  } else {
    // Else, the linenumber table is at the end of the constMethod.
    return last_u2_element();
  }
}


// Update the flags to indicate the presence of these optional fields.
void constMethodOopDesc::set_inlined_tables_length(
                                              int checked_exceptions_len,
                                              int compressed_line_number_size,
                                              int localvariable_table_len) {
  // Must be done in the order below, otherwise length_addr accessors
  // will not work. Only set bit in header if length is positive.
  assert(_flags == 0, "Error");
  if (compressed_line_number_size > 0) {
    _flags |= _has_linenumber_table;
  }
  if (checked_exceptions_len > 0) {
    _flags |= _has_checked_exceptions;
    *(checked_exceptions_length_addr()) = checked_exceptions_len;
  }
  if (localvariable_table_len > 0) {
    _flags |= _has_localvariable_table;
    *(localvariable_table_length_addr()) = localvariable_table_len;
  }
}


int constMethodOopDesc::checked_exceptions_length() const {
  return has_checked_exceptions() ? *(checked_exceptions_length_addr()) : 0;
}


CheckedExceptionElement* constMethodOopDesc::checked_exceptions_start() const {
  u2* addr = checked_exceptions_length_addr();
  u2 length = *addr;
  assert(length > 0, "should only be called if table is present");
  addr -= length * sizeof(CheckedExceptionElement) / sizeof(u2);
  return (CheckedExceptionElement*) addr;
}


int constMethodOopDesc::localvariable_table_length() const {
  return has_localvariable_table() ? *(localvariable_table_length_addr()) : 0;
}


LocalVariableTableElement* constMethodOopDesc::localvariable_table_start() const {
  u2* addr = localvariable_table_length_addr();
  u2 length = *addr;
  assert(length > 0, "should only be called if table is present");
  addr -= length * sizeof(LocalVariableTableElement) / sizeof(u2);
  return (LocalVariableTableElement*) addr;
}