/*

 * Copyright (c) 2000, 2013, 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 "classfile/systemDictionary.hpp"

#include "interpreter/bytecode.hpp"

#include "interpreter/bytecodeStream.hpp"

#include "interpreter/linkResolver.hpp"

#include "memory/heapInspection.hpp"

#include "oops/methodData.hpp"

#include "prims/jvmtiRedefineClasses.hpp"

#include "runtime/compilationPolicy.hpp"

#include "runtime/deoptimization.hpp"

#include "runtime/handles.inline.hpp"

// ==================================================================

// DataLayout

//

// Overlay for generic profiling data.

// Some types of data layouts need a length field.

bool DataLayout::needs_array_len(u1 tag) {

  return (tag == multi_branch_data_tag) || (tag == arg_info_data_tag);

}

// Perform generic initialization of the data.  More specific

// initialization occurs in overrides of ProfileData::post_initialize.

void DataLayout::initialize(u1 tag, u2 bci, int cell_count) {

  _header._bits = (intptr_t)0;

  _header._struct._tag = tag;

  _header._struct._bci = bci;

  for (int i = 0; i < cell_count; i++) {

    set_cell_at(i, (intptr_t)0);

  }

  if (needs_array_len(tag)) {

    set_cell_at(ArrayData::array_len_off_set, cell_count - 1); // -1 for header.

  }

}

void DataLayout::clean_weak_klass_links(BoolObjectClosure* cl) {

  ResourceMark m;

  data_in()->clean_weak_klass_links(cl);

}

// ==================================================================

// ProfileData

//

// A ProfileData object is created to refer to a section of profiling

// data in a structured way.

// Constructor for invalid ProfileData.

ProfileData::ProfileData() {

  _data = NULL;

}

#ifndef PRODUCT

  st->print("bci: %d", bci());

  st->fill_to(tab_width_one);

  st->print("%s", name);

  tab(st);

  int trap = trap_state();

  if (trap != 0) {

    char buf[100];

    st->print("trap(%s) ", Deoptimization::format_trap_state(buf, sizeof(buf), trap));

  }

  int flags = data()->flags();

  if (flags != 0)

    st->print("flags(%d) ", flags);

}

}

#endif // !PRODUCT

// ==================================================================

// BitData

//

// A BitData corresponds to a one-bit flag.  This is used to indicate

// whether a checkcast bytecode has seen a null value.

#ifndef PRODUCT

  print_shared(st, "BitData");

}

#endif // !PRODUCT

// ==================================================================

// CounterData

//

// A CounterData corresponds to a simple counter.

#ifndef PRODUCT

  print_shared(st, "CounterData");

  st->print_cr("count(%u)", count());

}

#endif // !PRODUCT

// ==================================================================

// JumpData

//

// A JumpData is used to access profiling information for a direct

// branch.  It is a counter, used for counting the number of branches,

// plus a data displacement, used for realigning the data pointer to

// the corresponding target bci.

void JumpData::post_initialize(BytecodeStream* stream, MethodData* mdo) {

  assert(stream->bci() == bci(), "wrong pos");

  int target;

  Bytecodes::Code c = stream->code();

  if (c == Bytecodes::_goto_w || c == Bytecodes::_jsr_w) {

    target = stream->dest_w();

  } else {

    target = stream->dest();

  }

  int my_di = mdo->dp_to_di(dp());

  int target_di = mdo->bci_to_di(target);

  int offset = target_di - my_di;

  set_displacement(offset);

}

#ifndef PRODUCT

  print_shared(st, "JumpData");

  st->print_cr("taken(%u) displacement(%d)", taken(), displacement());

}

#endif // !PRODUCT

// ==================================================================

// ReceiverTypeData

//

// A ReceiverTypeData is used to access profiling information about a

// dynamic type check.  It consists of a counter which counts the total times

// that the check is reached, and a series of (Klass*, count) pairs

// which are used to store a type profile for the receiver of the check.

void ReceiverTypeData::clean_weak_klass_links(BoolObjectClosure* is_alive_cl) {

    for (uint row = 0; row < row_limit(); row++) {

    Klass* p = receiver(row);

    if (p != NULL && !p->is_loader_alive(is_alive_cl)) {

      clear_row(row);

    }

  }

}

#ifndef PRODUCT

  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);

  int total = count();

  for (row = 0; row < row_limit(); row++) {

    if (receiver(row) != NULL) {

      total += receiver_count(row);

    }

  }

  for (row = 0; row < row_limit(); row++) {

    if (receiver(row) != NULL) {

      tab(st);

      receiver(row)->print_value_on(st);

      st->print_cr("(%u %4.2f)", receiver_count(row), (float) receiver_count(row) / (float) total);

    }

  }

}

  print_shared(st, "ReceiverTypeData");

  print_receiver_data_on(st);

}

  print_shared(st, "VirtualCallData");

  print_receiver_data_on(st);

}

#endif // !PRODUCT

// ==================================================================

// RetData

//

// A RetData is used to access profiling information for a ret bytecode.

// It is composed of a count of the number of times that the ret has

// been executed, followed by a series of triples of the form

// (bci, count, di) which count the number of times that some bci was the

// target of the ret and cache a corresponding displacement.

void RetData::post_initialize(BytecodeStream* stream, MethodData* mdo) {

  for (uint row = 0; row < row_limit(); row++) {

    set_bci_displacement(row, -1);

    set_bci(row, no_bci);

  }

  // release so other threads see a consistent state.  bci is used as

  // a valid flag for bci_displacement.

  OrderAccess::release();

}

// This routine needs to atomically update the RetData structure, so the

// caller needs to hold the RetData_lock before it gets here.  Since taking

// the lock can block (and allow GC) and since RetData is a ProfileData is a

// wrapper around a derived oop, taking the lock in _this_ method will

// basically cause the 'this' pointer's _data field to contain junk after the

// lock.  We require the caller to take the lock before making the ProfileData

// structure.  Currently the only caller is InterpreterRuntime::update_mdp_for_ret

address RetData::fixup_ret(int return_bci, MethodData* h_mdo) {

  // First find the mdp which corresponds to the return bci.

  address mdp = h_mdo->bci_to_dp(return_bci);

  // Now check to see if any of the cache slots are open.

  for (uint row = 0; row < row_limit(); row++) {

    if (bci(row) == no_bci) {

      set_bci_displacement(row, mdp - dp());

      set_bci_count(row, DataLayout::counter_increment);

      // Barrier to ensure displacement is written before the bci; allows

      // the interpreter to read displacement without fear of race condition.

      release_set_bci(row, return_bci);

      break;

    }

  }

  return mdp;

}

#ifndef PRODUCT

  print_shared(st, "RetData");

  uint row;

  int entries = 0;

  for (row = 0; row < row_limit(); row++) {

    if (bci(row) != no_bci)  entries++;

  }

  st->print_cr("count(%u) entries(%u)", count(), entries);

  for (row = 0; row < row_limit(); row++) {

    if (bci(row) != no_bci) {

      tab(st);

      st->print_cr("bci(%d: count(%u) displacement(%d))",

                   bci(row), bci_count(row), bci_displacement(row));

    }

  }

}

#endif // !PRODUCT

// ==================================================================

// BranchData

//

// A BranchData is used to access profiling data for a two-way branch.

// It consists of taken and not_taken counts as well as a data displacement

// for the taken case.

void BranchData::post_initialize(BytecodeStream* stream, MethodData* mdo) {

  assert(stream->bci() == bci(), "wrong pos");

  int target = stream->dest();

  int my_di = mdo->dp_to_di(dp());

  int target_di = mdo->bci_to_di(target);

  int offset = target_di - my_di;

  set_displacement(offset);

}

#ifndef PRODUCT

  print_shared(st, "BranchData");

  st->print_cr("taken(%u) displacement(%d)",

               taken(), displacement());

  tab(st);

  st->print_cr("not taken(%u)", not_taken());

}

#endif

// ==================================================================

// MultiBranchData

//

// A MultiBranchData is used to access profiling information for

// a multi-way branch (*switch bytecodes).  It consists of a series

// of (count, displacement) pairs, which count the number of times each

// case was taken and specify the data displacment for each branch target.

int MultiBranchData::compute_cell_count(BytecodeStream* stream) {

  int cell_count = 0;

  if (stream->code() == Bytecodes::_tableswitch) {

    Bytecode_tableswitch sw(stream->method()(), stream->bcp());

    cell_count = 1 + per_case_cell_count * (1 + sw.length()); // 1 for default

  } else {

    Bytecode_lookupswitch sw(stream->method()(), stream->bcp());

    cell_count = 1 + per_case_cell_count * (sw.number_of_pairs() + 1); // 1 for default

  }

  return cell_count;

}

void MultiBranchData::post_initialize(BytecodeStream* stream,

                                      MethodData* mdo) {

  assert(stream->bci() == bci(), "wrong pos");

  int target;

  int my_di;

  int target_di;

  int offset;

  if (stream->code() == Bytecodes::_tableswitch) {

    Bytecode_tableswitch sw(stream->method()(), stream->bcp());

    int len = sw.length();

    assert(array_len() == per_case_cell_count * (len + 1), "wrong len");

    for (int count = 0; count < len; count++) {

      target = sw.dest_offset_at(count) + bci();

      my_di = mdo->dp_to_di(dp());

      target_di = mdo->bci_to_di(target);

      offset = target_di - my_di;

      set_displacement_at(count, offset);

    }

    target = sw.default_offset() + bci();

    my_di = mdo->dp_to_di(dp());

    target_di = mdo->bci_to_di(target);

    offset = target_di - my_di;

    set_default_displacement(offset);

  } else {

    Bytecode_lookupswitch sw(stream->method()(), stream->bcp());

    int npairs = sw.number_of_pairs();

    assert(array_len() == per_case_cell_count * (npairs + 1), "wrong len");

    for (int count = 0; count < npairs; count++) {

      LookupswitchPair pair = sw.pair_at(count);

      target = pair.offset() + bci();

      my_di = mdo->dp_to_di(dp());

      target_di = mdo->bci_to_di(target);

      offset = target_di - my_di;

      set_displacement_at(count, offset);

    }

    target = sw.default_offset() + bci();

    my_di = mdo->dp_to_di(dp());

    target_di = mdo->bci_to_di(target);

    offset = target_di - my_di;

    set_default_displacement(offset);

  }

}

#ifndef PRODUCT

  print_shared(st, "MultiBranchData");

  st->print_cr("default_count(%u) displacement(%d)",

               default_count(), default_displacement());

  int cases = number_of_cases();

  for (int i = 0; i < cases; i++) {

    tab(st);

    st->print_cr("count(%u) displacement(%d)",

                 count_at(i), displacement_at(i));

  }

}

#endif

#ifndef PRODUCT

  print_shared(st, "ArgInfoData");

  int nargs = number_of_args();

  for (int i = 0; i < nargs; i++) {

    st->print("  0x%x", arg_modified(i));

  }

  st->cr();

}

#endif

// ==================================================================

// MethodData*

//

// A MethodData* holds information which has been collected about

// a method.