view src/share/vm/ci/ciMethodData.cpp @ 1994:6cd6d394f280

7001033: assert(gch->gc_cause() == GCCause::_scavenge_alot || !gch->incremental_collection_failed()) 7002546: regression on SpecJbb2005 on 7b118 comparing to 7b117 on small heaps Summary: Relaxed assertion checking related to incremental_collection_failed flag to allow for ExplicitGCInvokesConcurrent behaviour where we do not want a failing scavenge to bail to a stop-world collection. Parameterized incremental_collection_will_fail() so we can selectively use, or not use, as appropriate, the statistical prediction at specific use sites. This essentially reverts the scavenge bail-out logic to what it was prior to some recent changes that had inadvertently started using the statistical prediction which can be noisy in the presence of bursty loads. Added some associated verbose non-product debugging messages. Reviewed-by: johnc, tonyp
author ysr
date Tue, 07 Dec 2010 21:55:53 -0800
parents f95d63e2154a
children da91efe96a93
line wrap: on
line source

/*
 * Copyright (c) 2001, 2010, 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/ciMethodData.hpp"
#include "ci/ciUtilities.hpp"
#include "memory/allocation.inline.hpp"
#include "memory/resourceArea.hpp"
#include "runtime/deoptimization.hpp"
#include "utilities/copy.hpp"

// ciMethodData

// ------------------------------------------------------------------
// ciMethodData::ciMethodData
//
ciMethodData::ciMethodData(methodDataHandle h_md) : ciObject(h_md) {
  assert(h_md() != NULL, "no null method data");
  Copy::zero_to_words((HeapWord*) &_orig, sizeof(_orig) / sizeof(HeapWord));
  _data = NULL;
  _data_size = 0;
  _extra_data_size = 0;
  _current_mileage = 0;
  _invocation_counter = 0;
  _backedge_counter = 0;
  _state = empty_state;
  _saw_free_extra_data = false;
  // Set an initial hint. Don't use set_hint_di() because
  // first_di() may be out of bounds if data_size is 0.
  _hint_di = first_di();
  // Initialize the escape information (to "don't know.");
  _eflags = _arg_local = _arg_stack = _arg_returned = 0;
}

// ------------------------------------------------------------------
// ciMethodData::ciMethodData
//
// No methodDataOop.
ciMethodData::ciMethodData() : ciObject() {
  Copy::zero_to_words((HeapWord*) &_orig, sizeof(_orig) / sizeof(HeapWord));
  _data = NULL;
  _data_size = 0;
  _extra_data_size = 0;
  _current_mileage = 0;
  _invocation_counter = 0;
  _backedge_counter = 0;
  _state = empty_state;
  _saw_free_extra_data = false;
  // Set an initial hint. Don't use set_hint_di() because
  // first_di() may be out of bounds if data_size is 0.
  _hint_di = first_di();
  // Initialize the escape information (to "don't know.");
  _eflags = _arg_local = _arg_stack = _arg_returned = 0;
}

void ciMethodData::load_data() {
  methodDataOop mdo = get_methodDataOop();
  if (mdo == NULL) return;

  // To do: don't copy the data if it is not "ripe" -- require a minimum #
  // of invocations.

  // Snapshot the data -- actually, take an approximate snapshot of
  // the data.  Any concurrently executing threads may be changing the
  // data as we copy it.
  int skip_header = oopDesc::header_size();
  Copy::disjoint_words((HeapWord*) mdo              + skip_header,
                       (HeapWord*) &_orig           + skip_header,
                       sizeof(_orig) / HeapWordSize - skip_header);
  DEBUG_ONLY(*_orig.adr_method() = NULL);  // no dangling oops, please
  Arena* arena = CURRENT_ENV->arena();
  _data_size = mdo->data_size();
  _extra_data_size = mdo->extra_data_size();
  int total_size = _data_size + _extra_data_size;
  _data = (intptr_t *) arena->Amalloc(total_size);
  Copy::disjoint_words((HeapWord*) mdo->data_base(), (HeapWord*) _data, total_size / HeapWordSize);

  // Traverse the profile data, translating any oops into their
  // ci equivalents.
  ResourceMark rm;
  ciProfileData* ci_data = first_data();
  ProfileData* data = mdo->first_data();
  while (is_valid(ci_data)) {
    ci_data->translate_from(data);
    ci_data = next_data(ci_data);
    data = mdo->next_data(data);
  }
  // Note:  Extra data are all BitData, and do not need translation.
  _current_mileage = methodDataOopDesc::mileage_of(mdo->method());
  _invocation_counter = mdo->invocation_count();
  _backedge_counter = mdo->backedge_count();
  _state = mdo->is_mature()? mature_state: immature_state;

  _eflags = mdo->eflags();
  _arg_local = mdo->arg_local();
  _arg_stack = mdo->arg_stack();
  _arg_returned  = mdo->arg_returned();
}

void ciReceiverTypeData::translate_receiver_data_from(ProfileData* data) {
  for (uint row = 0; row < row_limit(); row++) {
    klassOop k = data->as_ReceiverTypeData()->receiver(row);
    if (k != NULL) {
      ciKlass* klass = CURRENT_ENV->get_object(k)->as_klass();
      set_receiver(row, klass);
    }
  }
}


// Get the data at an arbitrary (sort of) data index.
ciProfileData* ciMethodData::data_at(int data_index) {
  if (out_of_bounds(data_index)) {
    return NULL;
  }
  DataLayout* data_layout = data_layout_at(data_index);

  switch (data_layout->tag()) {
  case DataLayout::no_tag:
  default:
    ShouldNotReachHere();
    return NULL;
  case DataLayout::bit_data_tag:
    return new ciBitData(data_layout);
  case DataLayout::counter_data_tag:
    return new ciCounterData(data_layout);
  case DataLayout::jump_data_tag:
    return new ciJumpData(data_layout);
  case DataLayout::receiver_type_data_tag:
    return new ciReceiverTypeData(data_layout);
  case DataLayout::virtual_call_data_tag:
    return new ciVirtualCallData(data_layout);
  case DataLayout::ret_data_tag:
    return new ciRetData(data_layout);
  case DataLayout::branch_data_tag:
    return new ciBranchData(data_layout);
  case DataLayout::multi_branch_data_tag:
    return new ciMultiBranchData(data_layout);
  case DataLayout::arg_info_data_tag:
    return new ciArgInfoData(data_layout);
  };
}

// Iteration over data.
ciProfileData* ciMethodData::next_data(ciProfileData* current) {
  int current_index = dp_to_di(current->dp());
  int next_index = current_index + current->size_in_bytes();
  ciProfileData* next = data_at(next_index);
  return next;
}

// Translate a bci to its corresponding data, or NULL.
ciProfileData* ciMethodData::bci_to_data(int bci) {
  ciProfileData* data = data_before(bci);
  for ( ; is_valid(data); data = next_data(data)) {
    if (data->bci() == bci) {
      set_hint_di(dp_to_di(data->dp()));
      return data;
    } else if (data->bci() > bci) {
      break;
    }
  }
  // bci_to_extra_data(bci) ...
  DataLayout* dp  = data_layout_at(data_size());
  DataLayout* end = data_layout_at(data_size() + extra_data_size());
  for (; dp < end; dp = methodDataOopDesc::next_extra(dp)) {
    if (dp->tag() == DataLayout::no_tag) {
      _saw_free_extra_data = true;  // observed an empty slot (common case)
      return NULL;
    }
    if (dp->tag() == DataLayout::arg_info_data_tag) {
      break; // ArgInfoData is at the end of extra data section.
    }
    if (dp->bci() == bci) {
      assert(dp->tag() == DataLayout::bit_data_tag, "sane");
      return new ciBitData(dp);
    }
  }
  return NULL;
}

// Conservatively decode the trap_state of a ciProfileData.
int ciMethodData::has_trap_at(ciProfileData* data, int reason) {
  typedef Deoptimization::DeoptReason DR_t;
  int per_bc_reason
    = Deoptimization::reason_recorded_per_bytecode_if_any((DR_t) reason);
  if (trap_count(reason) == 0) {
    // Impossible for this trap to have occurred, regardless of trap_state.
    // Note:  This happens if the MDO is empty.
    return 0;
  } else if (per_bc_reason == Deoptimization::Reason_none) {
    // We cannot conclude anything; a trap happened somewhere, maybe here.
    return -1;
  } else if (data == NULL) {
    // No profile here, not even an extra_data record allocated on the fly.
    // If there are empty extra_data records, and there had been a trap,
    // there would have been a non-null data pointer.  If there are no
    // free extra_data records, we must return a conservative -1.
    if (_saw_free_extra_data)
      return 0;                 // Q.E.D.
    else
      return -1;                // bail with a conservative answer
  } else {
    return Deoptimization::trap_state_has_reason(data->trap_state(), per_bc_reason);
  }
}

int ciMethodData::trap_recompiled_at(ciProfileData* data) {
  if (data == NULL) {
    return (_saw_free_extra_data? 0: -1);  // (see previous method)
  } else {
    return Deoptimization::trap_state_is_recompiled(data->trap_state())? 1: 0;
  }
}

void ciMethodData::clear_escape_info() {
  VM_ENTRY_MARK;
  methodDataOop mdo = get_methodDataOop();
  if (mdo != NULL) {
    mdo->clear_escape_info();
    ArgInfoData *aid = arg_info();
    int arg_count = (aid == NULL) ? 0 : aid->number_of_args();
    for (int i = 0; i < arg_count; i++) {
      set_arg_modified(i, 0);
    }
  }
  _eflags = _arg_local = _arg_stack = _arg_returned = 0;
}

// copy our escape info to the methodDataOop if it exists
void ciMethodData::update_escape_info() {
  VM_ENTRY_MARK;
  methodDataOop mdo = get_methodDataOop();
  if ( mdo != NULL) {
    mdo->set_eflags(_eflags);
    mdo->set_arg_local(_arg_local);
    mdo->set_arg_stack(_arg_stack);
    mdo->set_arg_returned(_arg_returned);
    int arg_count = mdo->method()->size_of_parameters();
    for (int i = 0; i < arg_count; i++) {
      mdo->set_arg_modified(i, arg_modified(i));
    }
  }
}

void ciMethodData::set_compilation_stats(short loops, short blocks) {
  VM_ENTRY_MARK;
  methodDataOop mdo = get_methodDataOop();
  if (mdo != NULL) {
    mdo->set_num_loops(loops);
    mdo->set_num_blocks(blocks);
  }
}

void ciMethodData::set_would_profile(bool p) {
  VM_ENTRY_MARK;
  methodDataOop mdo = get_methodDataOop();
  if (mdo != NULL) {
    mdo->set_would_profile(p);
  }
}

bool ciMethodData::has_escape_info() {
  return eflag_set(methodDataOopDesc::estimated);
}

void ciMethodData::set_eflag(methodDataOopDesc::EscapeFlag f) {
  set_bits(_eflags, f);
}

void ciMethodData::clear_eflag(methodDataOopDesc::EscapeFlag f) {
  clear_bits(_eflags, f);
}

bool ciMethodData::eflag_set(methodDataOopDesc::EscapeFlag f) const {
  return mask_bits(_eflags, f) != 0;
}

void ciMethodData::set_arg_local(int i) {
  set_nth_bit(_arg_local, i);
}

void ciMethodData::set_arg_stack(int i) {
  set_nth_bit(_arg_stack, i);
}

void ciMethodData::set_arg_returned(int i) {
  set_nth_bit(_arg_returned, i);
}

void ciMethodData::set_arg_modified(int arg, uint val) {
  ArgInfoData *aid = arg_info();
  if (aid == NULL)
    return;
  assert(arg >= 0 && arg < aid->number_of_args(), "valid argument number");
  aid->set_arg_modified(arg, val);
}

bool ciMethodData::is_arg_local(int i) const {
  return is_set_nth_bit(_arg_local, i);
}

bool ciMethodData::is_arg_stack(int i) const {
  return is_set_nth_bit(_arg_stack, i);
}

bool ciMethodData::is_arg_returned(int i) const {
  return is_set_nth_bit(_arg_returned, i);
}

uint ciMethodData::arg_modified(int arg) const {
  ArgInfoData *aid = arg_info();
  if (aid == NULL)
    return 0;
  assert(arg >= 0 && arg < aid->number_of_args(), "valid argument number");
  return aid->arg_modified(arg);
}

ByteSize ciMethodData::offset_of_slot(ciProfileData* data, ByteSize slot_offset_in_data) {
  // Get offset within methodDataOop of the data array
  ByteSize data_offset = methodDataOopDesc::data_offset();

  // Get cell offset of the ProfileData within data array
  int cell_offset = dp_to_di(data->dp());

  // Add in counter_offset, the # of bytes into the ProfileData of counter or flag
  int offset = in_bytes(data_offset) + cell_offset + in_bytes(slot_offset_in_data);

  return in_ByteSize(offset);
}

ciArgInfoData *ciMethodData::arg_info() const {
  // Should be last, have to skip all traps.
  DataLayout* dp  = data_layout_at(data_size());
  DataLayout* end = data_layout_at(data_size() + extra_data_size());
  for (; dp < end; dp = methodDataOopDesc::next_extra(dp)) {
    if (dp->tag() == DataLayout::arg_info_data_tag)
      return new ciArgInfoData(dp);
  }
  return NULL;
}


// Implementation of the print method.
void ciMethodData::print_impl(outputStream* st) {
  ciObject::print_impl(st);
}

#ifndef PRODUCT
void ciMethodData::print() {
  print_data_on(tty);
}

void ciMethodData::print_data_on(outputStream* st) {
  ResourceMark rm;
  ciProfileData* data;
  for (data = first_data(); is_valid(data); data = next_data(data)) {
    st->print("%d", dp_to_di(data->dp()));
    st->fill_to(6);
    data->print_data_on(st);
  }
  st->print_cr("--- Extra data:");
  DataLayout* dp  = data_layout_at(data_size());
  DataLayout* end = data_layout_at(data_size() + extra_data_size());
  for (; dp < end; dp = methodDataOopDesc::next_extra(dp)) {
    if (dp->tag() == DataLayout::no_tag)  continue;
    if (dp->tag() == DataLayout::bit_data_tag) {
      data = new BitData(dp);
    } else {
      assert(dp->tag() == DataLayout::arg_info_data_tag, "must be BitData or ArgInfo");
      data = new ciArgInfoData(dp);
      dp = end; // ArgInfoData is at the end of extra data section.
    }
    st->print("%d", dp_to_di(data->dp()));
    st->fill_to(6);
    data->print_data_on(st);
  }
}

void ciReceiverTypeData::print_receiver_data_on(outputStream* st) {
  uint row;
  int entries = 0;
  for (row = 0; row < row_limit(); row++) {
    if (receiver(row) != NULL)  entries++;
  }
  st->print_cr("count(%u) entries(%u)", count(), entries);
  for (row = 0; row < row_limit(); row++) {
    if (receiver(row) != NULL) {
      tab(st);
      receiver(row)->print_name_on(st);
      st->print_cr("(%u)", receiver_count(row));
    }
  }
}

void ciReceiverTypeData::print_data_on(outputStream* st) {
  print_shared(st, "ciReceiverTypeData");
  print_receiver_data_on(st);
}

void ciVirtualCallData::print_data_on(outputStream* st) {
  print_shared(st, "ciVirtualCallData");
  rtd_super()->print_receiver_data_on(st);
}
#endif