/*

 * Copyright (c) 1997, 2011, 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/vmSymbols.hpp"

#include "interpreter/interpreter.hpp"

#include "memory/allocation.inline.hpp"

#include "memory/resourceArea.hpp"

#include "memory/universe.inline.hpp"

#include "oops/methodDataOop.hpp"

#include "oops/oop.inline.hpp"

#include "prims/jvmtiThreadState.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/monitorChunk.hpp"

#include "runtime/sharedRuntime.hpp"

#include "runtime/vframe.hpp"

#include "runtime/vframeArray.hpp"

#include "runtime/vframe_hp.hpp"

#include "utilities/events.hpp"

#ifdef COMPILER2

#include "opto/runtime.hpp"

#endif

int vframeArrayElement:: bci(void) const { return (_bci == SynchronizationEntryBCI ? 0 : _bci); }

void vframeArrayElement::free_monitors(JavaThread* jt) {

  if (_monitors != NULL) {

     MonitorChunk* chunk = _monitors;

     _monitors = NULL;

     jt->remove_monitor_chunk(chunk);

     delete chunk;

  }

}

void vframeArrayElement::fill_in(compiledVFrame* vf) {

// Copy the information from the compiled vframe to the

// interpreter frame we will be creating to replace vf

  _method = vf->method();

  _bci    = vf->raw_bci();

  _reexecute = vf->should_reexecute();

  int index;

  // Get the monitors off-stack

  GrowableArray<MonitorInfo*>* list = vf->monitors();

  if (list->is_empty()) {

    _monitors = NULL;

  } else {

    // Allocate monitor chunk

    _monitors = new MonitorChunk(list->length());

    vf->thread()->add_monitor_chunk(_monitors);

    // Migrate the BasicLocks from the stack to the monitor chunk

    for (index = 0; index < list->length(); index++) {

      MonitorInfo* monitor = list->at(index);

      assert(!monitor->owner_is_scalar_replaced(), "object should be reallocated already");

      assert(monitor->owner() == NULL || (!monitor->owner()->is_unlocked() && !monitor->owner()->has_bias_pattern()), "object must be null or locked, and unbiased");

      BasicObjectLock* dest = _monitors->at(index);

      dest->set_obj(monitor->owner());

      monitor->lock()->move_to(monitor->owner(), dest->lock());

    }

  }

  // Convert the vframe locals and expressions to off stack

  // values. Because we will not gc all oops can be converted to

  // intptr_t (i.e. a stack slot) and we are fine. This is

  // good since we are inside a HandleMark and the oops in our

  // collection would go away between packing them here and

  // unpacking them in unpack_on_stack.

  // First the locals go off-stack

  // FIXME this seems silly it creates a StackValueCollection

  // in order to get the size to then copy them and

  // convert the types to intptr_t size slots. Seems like it

  // could do it in place... Still uses less memory than the

  // old way though

  StackValueCollection *locs = vf->locals();

  _locals = new StackValueCollection(locs->size());

  for(index = 0; index < locs->size(); index++) {

    StackValue* value = locs->at(index);

    switch(value->type()) {

      case T_OBJECT:

        assert(!value->obj_is_scalar_replaced(), "object should be reallocated already");

        // preserve object type

        _locals->add( new StackValue((intptr_t) (value->get_obj()()), T_OBJECT ));

        break;

      case T_CONFLICT:

        // A dead local.  Will be initialized to null/zero.

        _locals->add( new StackValue());

        break;

      case T_INT:

        _locals->add( new StackValue(value->get_int()));

        break;

      default:

        ShouldNotReachHere();

    }

  }

  // Now the expressions off-stack

  // Same silliness as above

  StackValueCollection *exprs = vf->expressions();

  _expressions = new StackValueCollection(exprs->size());

  for(index = 0; index < exprs->size(); index++) {

    StackValue* value = exprs->at(index);

    switch(value->type()) {

      case T_OBJECT:

        assert(!value->obj_is_scalar_replaced(), "object should be reallocated already");

        // preserve object type

        _expressions->add( new StackValue((intptr_t) (value->get_obj()()), T_OBJECT ));

        break;

      case T_CONFLICT:

        // A dead stack element.  Will be initialized to null/zero.

        // This can occur when the compiler emits a state in which stack

        // elements are known to be dead (because of an imminent exception).

        _expressions->add( new StackValue());

        break;

      case T_INT:

        _expressions->add( new StackValue(value->get_int()));

        break;

      default:

        ShouldNotReachHere();

    }

  }

}

int unpack_counter = 0;

void vframeArrayElement::unpack_on_stack(int caller_actual_parameters,

                                         int callee_parameters,

                                         int callee_locals,

                                         frame* caller,

                                         bool is_top_frame,

                                         int exec_mode) {

  JavaThread* thread = (JavaThread*) Thread::current();

  // Look at bci and decide on bcp and continuation pc

  address bcp;

  // C++ interpreter doesn't need a pc since it will figure out what to do when it

  // begins execution

  address pc;

  bool use_next_mdp = false; // true if we should use the mdp associated with the next bci

                             // rather than the one associated with bcp

  if (raw_bci() == SynchronizationEntryBCI) {

    // We are deoptimizing while hanging in prologue code for synchronized method

    bcp = method()->bcp_from(0); // first byte code

    pc  = Interpreter::deopt_entry(vtos, 0); // step = 0 since we don't skip current bytecode

  } else if (should_reexecute()) { //reexecute this bytecode

    assert(is_top_frame, "reexecute allowed only for the top frame");

    bcp = method()->bcp_from(bci());

    pc  = Interpreter::deopt_reexecute_entry(method(), bcp);

  } else {

    bcp = method()->bcp_from(bci());

    pc  = Interpreter::deopt_continue_after_entry(method(), bcp, callee_parameters, is_top_frame);

    use_next_mdp = true;

  }

  assert(Bytecodes::is_defined(*bcp), "must be a valid bytecode");

  // Monitorenter and pending exceptions:

  //

  // For Compiler2, there should be no pending exception when deoptimizing at monitorenter

  // because there is no safepoint at the null pointer check (it is either handled explicitly

  // or prior to the monitorenter) and asynchronous exceptions are not made "pending" by the

  // runtime interface for the slow case (see JRT_ENTRY_FOR_MONITORENTER).  If an asynchronous

  // exception was processed, the bytecode pointer would have to be extended one bytecode beyond

  // the monitorenter to place it in the proper exception range.

  //

  // For Compiler1, deoptimization can occur while throwing a NullPointerException at monitorenter,

  // in which case bcp should point to the monitorenter since it is within the exception's range.

  assert(*bcp != Bytecodes::_monitorenter || is_top_frame, "a _monitorenter must be a top frame");

  assert(thread->deopt_nmethod() != NULL, "nmethod should be known");

  guarantee(!(thread->deopt_nmethod()->is_compiled_by_c2() &&

              *bcp == Bytecodes::_monitorenter             &&

              exec_mode == Deoptimization::Unpack_exception),

            "shouldn't get exception during monitorenter");

  int popframe_preserved_args_size_in_bytes = 0;

  int popframe_preserved_args_size_in_words = 0;

  if (is_top_frame) {

    JvmtiThreadState *state = thread->jvmti_thread_state();

    if (JvmtiExport::can_pop_frame() &&

        (thread->has_pending_popframe() || thread->popframe_forcing_deopt_reexecution())) {

      if (thread->has_pending_popframe()) {

        // Pop top frame after deoptimization

#ifndef CC_INTERP

        pc = Interpreter::remove_activation_preserving_args_entry();

#else

        // Do an uncommon trap type entry. c++ interpreter will know

        // to pop frame and preserve the args

        pc = Interpreter::deopt_entry(vtos, 0);

        use_next_mdp = false;

#endif

      } else {

        // Reexecute invoke in top frame

        pc = Interpreter::deopt_entry(vtos, 0);

        use_next_mdp = false;

        popframe_preserved_args_size_in_bytes = in_bytes(thread->popframe_preserved_args_size());

        // Note: the PopFrame-related extension of the expression stack size is done in

        // Deoptimization::fetch_unroll_info_helper

        popframe_preserved_args_size_in_words = in_words(thread->popframe_preserved_args_size_in_words());

      }

    } else if (JvmtiExport::can_force_early_return() && state != NULL && state->is_earlyret_pending()) {

      // Force early return from top frame after deoptimization

#ifndef CC_INTERP

      pc = Interpreter::remove_activation_early_entry(state->earlyret_tos());

#else

     // TBD: Need to implement ForceEarlyReturn for CC_INTERP (ia64)

#endif

    } else {

      // Possibly override the previous pc computation of the top (youngest) frame

      switch (exec_mode) {

      case Deoptimization::Unpack_deopt:

        // use what we've got

        break;

      case Deoptimization::Unpack_exception:

        // exception is pending

        pc = SharedRuntime::raw_exception_handler_for_return_address(thread, pc);

        // [phh] We're going to end up in some handler or other, so it doesn't

        // matter what mdp we point to.  See exception_handler_for_exception()

        // in interpreterRuntime.cpp.

        break;

      case Deoptimization::Unpack_uncommon_trap:

      case Deoptimization::Unpack_reexecute:

        // redo last byte code

        pc  = Interpreter::deopt_entry(vtos, 0);

        use_next_mdp = false;

        break;

      default:

        ShouldNotReachHere();

      }

    }

  }

  // Setup the interpreter frame

  assert(method() != NULL, "method must exist");

  int temps = expressions()->size();

  int locks = monitors() == NULL ? 0 : monitors()->number_of_monitors();

  Interpreter::layout_activation(method(),

                                 temps + callee_parameters,

                                 popframe_preserved_args_size_in_words,

                                 locks,

                                 caller_actual_parameters,

                                 callee_parameters,

                                 callee_locals,

                                 caller,

                                 iframe(),

                                 is_top_frame);

  // Update the pc in the frame object and overwrite the temporary pc

  // we placed in the skeletal frame now that we finally know the

  // exact interpreter address we should use.

  _frame.patch_pc(thread, pc);

  assert (!method()->is_synchronized() || locks > 0, "synchronized methods must have monitors");

  BasicObjectLock* top = iframe()->interpreter_frame_monitor_begin();

  for (int index = 0; index < locks; index++) {

    top = iframe()->previous_monitor_in_interpreter_frame(top);

    BasicObjectLock* src = _monitors->at(index);

    top->set_obj(src->obj());

    src->lock()->move_to(src->obj(), top->lock());

  }

  if (ProfileInterpreter) {

    iframe()->interpreter_frame_set_mdx(0); // clear out the mdp.

  }

  iframe()->interpreter_frame_set_bcx((intptr_t)bcp); // cannot use bcp because frame is not initialized yet

  if (ProfileInterpreter) {

    methodDataOop mdo = method()->method_data();

    if (mdo != NULL) {

      int bci = iframe()->interpreter_frame_bci();

      if (use_next_mdp) ++bci;

      address mdp = mdo->bci_to_dp(bci);

      iframe()->interpreter_frame_set_mdp(mdp);

    }

  }

  // Unpack expression stack

  // If this is an intermediate frame (i.e. not top frame) then this

  // only unpacks the part of the expression stack not used by callee

  // as parameters. The callee parameters are unpacked as part of the

  // callee locals.

  int i;

  for(i = 0; i < expressions()->size(); i++) {

    StackValue *value = expressions()->at(i);

    intptr_t*   addr  = iframe()->interpreter_frame_expression_stack_at(i);

    switch(value->type()) {

      case T_INT:

        *addr = value->get_int();

        break;

      case T_OBJECT:

        *addr = value->get_int(T_OBJECT);

        break;

      case T_CONFLICT:

        // A dead stack slot.  Initialize to null in case it is an oop.

        *addr = NULL_WORD;

        break;

      default:

        ShouldNotReachHere();

    }

  }

  // Unpack the locals

  for(i = 0; i < locals()->size(); i++) {

    StackValue *value = locals()->at(i);

    intptr_t* addr  = iframe()->interpreter_frame_local_at(i);

    switch(value->type()) {

      case T_INT:

        *addr = value->get_int();

        break;

      case T_OBJECT:

        *addr = value->get_int(T_OBJECT);

        break;

      case T_CONFLICT:

        // A dead location. If it is an oop then we need a NULL to prevent GC from following it

        *addr = NULL_WORD;

        break;

      default:

        ShouldNotReachHere();

    }

  }

  if (is_top_frame && JvmtiExport::can_pop_frame() && thread->popframe_forcing_deopt_reexecution()) {

    // An interpreted frame was popped but it returns to a deoptimized

    // frame. The incoming arguments to the interpreted activation

    // were preserved in thread-local storage by the

    // remove_activation_preserving_args_entry in the interpreter; now

    // we put them back into the just-unpacked interpreter frame.

    // Note that this assumes that the locals arena grows toward lower

    // addresses.

    if (popframe_preserved_args_size_in_words != 0) {

      void* saved_args = thread->popframe_preserved_args();

      assert(saved_args != NULL, "must have been saved by interpreter");

#ifdef ASSERT

      assert(popframe_preserved_args_size_in_words <=

             iframe()->interpreter_frame_expression_stack_size()*Interpreter::stackElementWords,

             "expression stack size should have been extended");

#endif // ASSERT

      int top_element = iframe()->interpreter_frame_expression_stack_size()-1;

      intptr_t* base;

      if (frame::interpreter_frame_expression_stack_direction() < 0) {

        base = iframe()->interpreter_frame_expression_stack_at(top_element);

      } else {

        base = iframe()->interpreter_frame_expression_stack();

      }

      Copy::conjoint_jbytes(saved_args,

                            base,

                            popframe_preserved_args_size_in_bytes);

      thread->popframe_free_preserved_args();

    }

  }

#ifndef PRODUCT

  if (TraceDeoptimization && Verbose) {

    ttyLocker ttyl;

    tty->print_cr("[%d Interpreted Frame]", ++unpack_counter);

    iframe()->print_on(tty);

    RegisterMap map(thread);

    vframe* f = vframe::new_vframe(iframe(), &map, thread);

    f->print();

    tty->print_cr("locals size     %d", locals()->size());

    tty->print_cr("expression size %d", expressions()->size());

    method()->print_value();

    tty->cr();

    // method()->print_codes();

  } else if (TraceDeoptimization) {

    tty->print("     ");

    method()->print_value();

    Bytecodes::Code code = Bytecodes::java_code_at(method(), bcp);

    int bci = method()->bci_from(bcp);

    tty->print(" - %s", Bytecodes::name(code));

    tty->print(" @ bci %d ", bci);

    tty->print_cr("sp = " PTR_FORMAT, iframe()->sp());

  }

#endif // PRODUCT

  // The expression stack and locals are in the resource area don't leave

  // a dangling pointer in the vframeArray we leave around for debug

  // purposes

  _locals = _expressions = NULL;

}

int vframeArrayElement::on_stack_size(int caller_actual_parameters,

                                      int callee_parameters,

                                      int callee_locals,

                                      bool is_top_frame,

                                      int popframe_extra_stack_expression_els) const {

  assert(method()->max_locals() == locals()->size(), "just checking");

  int locks = monitors() == NULL ? 0 : monitors()->number_of_monitors();

  int temps = expressions()->size();

  return Interpreter::size_activation(method(),

                                      temps + callee_parameters,

                                      popframe_extra_stack_expression_els,

                                      locks,

                                      caller_actual_parameters,

                                      callee_parameters,

                                      callee_locals,

                                      is_top_frame);

}

vframeArray* vframeArray::allocate(JavaThread* thread, int frame_size, GrowableArray<compiledVFrame*>* chunk,

                                   RegisterMap *reg_map, frame sender, frame caller, frame self) {

  // Allocate the vframeArray

  vframeArray * result = (vframeArray*) AllocateHeap(sizeof(vframeArray) + // fixed part

                                                     sizeof(vframeArrayElement) * (chunk->length() - 1), // variable part

                                                     "vframeArray::allocate");

  result->_frames = chunk->length();

  result->_owner_thread = thread;

  result->_sender = sender;

  result->_caller = caller;

  result->_original = self;

  result->set_unroll_block(NULL); // initialize it

  result->fill_in(thread, frame_size, chunk, reg_map);

  return result;

}

void vframeArray::fill_in(JavaThread* thread,

                          int frame_size,

                          GrowableArray<compiledVFrame*>* chunk,

                          const RegisterMap *reg_map) {

  // Set owner first, it is used when adding monitor chunks

  _frame_size = frame_size;

  for(int i = 0; i < chunk->length(); i++) {

    element(i)->fill_in(chunk->at(i));

  }

  // Copy registers for callee-saved registers

  if (reg_map != NULL) {

    for(int i = 0; i < RegisterMap::reg_count; i++) {

#ifdef AMD64

      // The register map has one entry for every int (32-bit value), so

      // 64-bit physical registers have two entries in the map, one for

      // each half.  Ignore the high halves of 64-bit registers, just like

      // frame::oopmapreg_to_location does.

      //

      // [phh] FIXME: this is a temporary hack!  This code *should* work

      // correctly w/o this hack, possibly by changing RegisterMap::pd_location

      // in frame_amd64.cpp and the values of the phantom high half registers

      // in amd64.ad.

      //      if (VMReg::Name(i) < SharedInfo::stack0 && is_even(i)) {

        intptr_t* src = (intptr_t*) reg_map->location(VMRegImpl::as_VMReg(i));

        _callee_registers[i] = src != NULL ? *src : NULL_WORD;

        //      } else {

        //      jint* src = (jint*) reg_map->location(VMReg::Name(i));

        //      _callee_registers[i] = src != NULL ? *src : NULL_WORD;

        //      }

#else

      jint* src = (jint*) reg_map->location(VMRegImpl::as_VMReg(i));

      _callee_registers[i] = src != NULL ? *src : NULL_WORD;

#endif

      if (src == NULL) {

        set_location_valid(i, false);

      } else {

        set_location_valid(i, true);

        jint* dst = (jint*) register_location(i);

        *dst = *src;

      }

    }

  }

}

void vframeArray::unpack_to_stack(frame &unpack_frame, int exec_mode, int caller_actual_parameters) {

  // stack picture

  //   unpack_frame

  //   [new interpreter frames ] (frames are skeletal but walkable)

  //   caller_frame

  //

  //  This routine fills in the missing data for the skeletal interpreter frames

  //  in the above picture.

  // Find the skeletal interpreter frames to unpack into

  RegisterMap map(JavaThread::current(), false);

  // Get the youngest frame we will unpack (last to be unpacked)

  frame me = unpack_frame.sender(&map);

  int index;

  for (index = 0; index < frames(); index++ ) {

    *element(index)->iframe() = me;

    // Get the caller frame (possibly skeletal)

    me = me.sender(&map);

  }