hotspot/src/share/vm/ci/ciMethodData.cpp
author minqi
Mon, 12 Nov 2012 14:03:53 -0800
changeset 14477 95e66ea71f71
parent 13728 882756847a04
child 15471 41f75023e6a6
permissions -rw-r--r--
6830717: replay of compilations would help with debugging Summary: When java process crashed in compiler thread, repeat the compilation process will help finding root cause. This is done with using SA dump application class data and replay data from core dump, then use debug version of jvm to recompile the problematic java method. Reviewed-by: kvn, twisti, sspitsyn Contributed-by: yumin.qi@oracle.com

/*
 * Copyright (c) 2001, 2012, 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/ciMetadata.hpp"
#include "ci/ciMethodData.hpp"
#include "ci/ciReplay.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(MethodData* md) : ciMetadata(md) {
  assert(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 MethodData*.
ciMethodData::ciMethodData() : ciMetadata(NULL) {
  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() {
  MethodData* mdo = get_MethodData();
  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.
  Copy::disjoint_words((HeapWord*) mdo,
                       (HeapWord*) &_orig,
                       sizeof(_orig) / HeapWordSize);
  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 = MethodData::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();
#ifndef PRODUCT
  if (ReplayCompiles) {
    ciReplay::initialize(this);
  }
#endif
}

void ciReceiverTypeData::translate_receiver_data_from(ProfileData* data) {
  for (uint row = 0; row < row_limit(); row++) {
    Klass* k = data->as_ReceiverTypeData()->receiver(row);
    if (k != NULL) {
      ciKlass* klass = CURRENT_ENV->get_klass(k);
      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 = MethodData::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;
  MethodData* mdo = get_MethodData();
  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 MethodData* if it exists
void ciMethodData::update_escape_info() {
  VM_ENTRY_MARK;
  MethodData* mdo = get_MethodData();
  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;
  MethodData* mdo = get_MethodData();
  if (mdo != NULL) {
    mdo->set_num_loops(loops);
    mdo->set_num_blocks(blocks);
  }
}

void ciMethodData::set_would_profile(bool p) {
  VM_ENTRY_MARK;
  MethodData* mdo = get_MethodData();
  if (mdo != NULL) {
    mdo->set_would_profile(p);
  }
}

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

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

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

bool ciMethodData::eflag_set(MethodData::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 MethodData* of the data array
  ByteSize data_offset = MethodData::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 = MethodData::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) {
  ciMetadata::print_impl(st);
}

void ciMethodData::dump_replay_data(outputStream* out) {
  ASSERT_IN_VM;
  MethodData* mdo = get_MethodData();
  Method* method = mdo->method();
  Klass* holder = method->method_holder();
  out->print("ciMethodData %s %s %s %d %d",
             holder->name()->as_quoted_ascii(),
             method->name()->as_quoted_ascii(),
             method->signature()->as_quoted_ascii(),
             _state,
             current_mileage());

  // dump the contents of the MDO header as raw data
  unsigned char* orig = (unsigned char*)&_orig;
  int length = sizeof(_orig);
  out->print(" orig %d", length);
  for (int i = 0; i < length; i++) {
    out->print(" %d", orig[i]);
  }

  // dump the MDO data as raw data
  int elements = data_size() / sizeof(intptr_t);
  out->print(" data %d", elements);
  for (int i = 0; i < elements; i++) {
    // We could use INTPTR_FORMAT here but that's a zero justified
    // which makes comparing it with the SA version of this output
    // harder.
#ifdef _LP64
    out->print(" 0x%" FORMAT64_MODIFIER "x", data()[i]);
#else
    out->print(" 0x%x", data()[i]);
#endif
  }

  // The MDO contained oop references as ciObjects, so scan for those
  // and emit pairs of offset and klass name so that they can be
  // reconstructed at runtime.  The first round counts the number of
  // oop references and the second actually emits them.
  int count = 0;
  for (int round = 0; round < 2; round++) {
    if (round == 1) out->print(" oops %d", count);
    ProfileData* pdata = first_data();
    for ( ; is_valid(pdata); pdata = next_data(pdata)) {
      if (pdata->is_ReceiverTypeData()) {
        ciReceiverTypeData* vdata = (ciReceiverTypeData*)pdata;
        for (uint i = 0; i < vdata->row_limit(); i++) {
          ciKlass* k = vdata->receiver(i);
          if (k != NULL) {
            if (round == 0) {
              count++;
            } else {
              out->print(" %d %s", dp_to_di(vdata->dp() + in_bytes(vdata->receiver_offset(i))) / sizeof(intptr_t), k->name()->as_quoted_ascii());
            }
          }
        }
      } else if (pdata->is_VirtualCallData()) {
        ciVirtualCallData* vdata = (ciVirtualCallData*)pdata;
        for (uint i = 0; i < vdata->row_limit(); i++) {
          ciKlass* k = vdata->receiver(i);
          if (k != NULL) {
            if (round == 0) {
              count++;
            } else {
              out->print(" %d %s", dp_to_di(vdata->dp() + in_bytes(vdata->receiver_offset(i))) / sizeof(intptr_t), k->name()->as_quoted_ascii());
            }
          }
        }
      }
    }
  }
  out->cr();
}

#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 = MethodData::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