/*

 * Copyright (c) 1997, 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 "incls/_precompiled.incl"

#include "incls/_interpreter.cpp.incl"

# define __ _masm->

//------------------------------------------------------------------------------------------------------------------------

// Implementation of InterpreterCodelet

void InterpreterCodelet::initialize(const char* description, Bytecodes::Code bytecode) {

  _description       = description;

  _bytecode          = bytecode;

}

void InterpreterCodelet::verify() {

}

void InterpreterCodelet::print() {

  if (PrintInterpreter) {

    tty->cr();

    tty->print_cr("----------------------------------------------------------------------");

  }

  if (description() != NULL) tty->print("%s  ", description());

  if (bytecode()    >= 0   ) tty->print("%d %s  ", bytecode(), Bytecodes::name(bytecode()));

  tty->print_cr("[" INTPTR_FORMAT ", " INTPTR_FORMAT "]  %d bytes",

                code_begin(), code_end(), code_size());

  if (PrintInterpreter) {

    tty->cr();

    Disassembler::decode(code_begin(), code_end(), tty);

  }

}

//------------------------------------------------------------------------------------------------------------------------

// Implementation of  platform independent aspects of Interpreter

void AbstractInterpreter::initialize() {

  if (_code != NULL) return;

  // make sure 'imported' classes are initialized

  if (CountBytecodes || TraceBytecodes || StopInterpreterAt) BytecodeCounter::reset();

  if (PrintBytecodeHistogram)                                BytecodeHistogram::reset();

  if (PrintBytecodePairHistogram)                            BytecodePairHistogram::reset();

  InvocationCounter::reinitialize(DelayCompilationDuringStartup);

}

void AbstractInterpreter::print() {

  tty->cr();

  tty->print_cr("----------------------------------------------------------------------");

  tty->print_cr("Interpreter");

  tty->cr();

  tty->print_cr("code size        = %6dK bytes", (int)_code->used_space()/1024);

  tty->print_cr("total space      = %6dK bytes", (int)_code->total_space()/1024);

  tty->print_cr("wasted space     = %6dK bytes", (int)_code->available_space()/1024);

  tty->cr();

  tty->print_cr("# of codelets    = %6d"      , _code->number_of_stubs());

  tty->print_cr("avg codelet size = %6d bytes", _code->used_space() / _code->number_of_stubs());

  tty->cr();

  _code->print();

  tty->print_cr("----------------------------------------------------------------------");

  tty->cr();

}

void interpreter_init() {

  Interpreter::initialize();

#ifndef PRODUCT

  if (TraceBytecodes) BytecodeTracer::set_closure(BytecodeTracer::std_closure());

#endif // PRODUCT

  // need to hit every safepoint in order to call zapping routine

  // register the interpreter

  VTune::register_stub(

    "Interpreter",

    AbstractInterpreter::code()->code_start(),

    AbstractInterpreter::code()->code_end()

  );

  Forte::register_stub(

    "Interpreter",

    AbstractInterpreter::code()->code_start(),

    AbstractInterpreter::code()->code_end()

  );

  // notify JVMTI profiler

  if (JvmtiExport::should_post_dynamic_code_generated()) {

    JvmtiExport::post_dynamic_code_generated("Interpreter",

                                             AbstractInterpreter::code()->code_start(),

                                             AbstractInterpreter::code()->code_end());

  }

}

//------------------------------------------------------------------------------------------------------------------------

// Implementation of interpreter

StubQueue* AbstractInterpreter::_code                                       = NULL;

bool       AbstractInterpreter::_notice_safepoints                          = false;

address    AbstractInterpreter::_rethrow_exception_entry                    = NULL;

address    AbstractInterpreter::_native_entry_begin                         = NULL;

address    AbstractInterpreter::_native_entry_end                           = NULL;

address    AbstractInterpreter::_slow_signature_handler;

address    AbstractInterpreter::_entry_table            [AbstractInterpreter::number_of_method_entries];

address    AbstractInterpreter::_native_abi_to_tosca    [AbstractInterpreter::number_of_result_handlers];

//------------------------------------------------------------------------------------------------------------------------

// Generation of complete interpreter

AbstractInterpreterGenerator::AbstractInterpreterGenerator(StubQueue* _code) {

  _masm                      = NULL;

}

static const BasicType types[Interpreter::number_of_result_handlers] = {

  T_BOOLEAN,

  T_CHAR   ,

  T_BYTE   ,

  T_SHORT  ,

  T_INT    ,

  T_LONG   ,

  T_VOID   ,

  T_FLOAT  ,

  T_DOUBLE ,

  T_OBJECT

};

void AbstractInterpreterGenerator::generate_all() {

  { CodeletMark cm(_masm, "slow signature handler");

    Interpreter::_slow_signature_handler = generate_slow_signature_handler();

  }

}

//------------------------------------------------------------------------------------------------------------------------

// Entry points

AbstractInterpreter::MethodKind AbstractInterpreter::method_kind(methodHandle m) {

  // Abstract method?

  if (m->is_abstract()) return abstract;

  // Invoker for method handles?

  if (m->is_method_handle_invoke())  return method_handle;

  // Native method?

  // Note: This test must come _before_ the test for intrinsic

  //       methods. See also comments below.

  if (m->is_native()) {

    assert(!m->is_method_handle_invoke(), "overlapping bits here, watch out");

    return m->is_synchronized() ? native_synchronized : native;

  }

  // Synchronized?

  if (m->is_synchronized()) {

    return zerolocals_synchronized;

  }

  if (RegisterFinalizersAtInit && m->code_size() == 1 &&

      m->intrinsic_id() == vmIntrinsics::_Object_init) {

    // We need to execute the special return bytecode to check for

    // finalizer registration so create a normal frame.

    return zerolocals;

  }

  // Empty method?

  if (m->is_empty_method()) {

    return empty;

  }

  // Accessor method?

  if (m->is_accessor()) {

    assert(m->size_of_parameters() == 1, "fast code for accessors assumes parameter size = 1");

    return accessor;

  }

  // Special intrinsic method?

  // Note: This test must come _after_ the test for native methods,

  //       otherwise we will run into problems with JDK 1.2, see also

  //       AbstractInterpreterGenerator::generate_method_entry() for

  //       for details.

  switch (m->intrinsic_id()) {

    case vmIntrinsics::_dsin  : return java_lang_math_sin  ;

    case vmIntrinsics::_dcos  : return java_lang_math_cos  ;

    case vmIntrinsics::_dtan  : return java_lang_math_tan  ;

    case vmIntrinsics::_dabs  : return java_lang_math_abs  ;

    case vmIntrinsics::_dsqrt : return java_lang_math_sqrt ;

    case vmIntrinsics::_dlog  : return java_lang_math_log  ;

    case vmIntrinsics::_dlog10: return java_lang_math_log10;

  }

  // Note: for now: zero locals for all non-empty methods

  return zerolocals;

}

// Return true if the interpreter can prove that the given bytecode has

// not yet been executed (in Java semantics, not in actual operation).

bool AbstractInterpreter::is_not_reached(methodHandle method, int bci) {

  address bcp = method->bcp_from(bci);

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

  if (!Bytecode_at(bcp)->must_rewrite(code)) {

    // might have been reached

    return false;

  }

  // the bytecode might not be rewritten if the method is an accessor, etc.

  address ientry = method->interpreter_entry();

  if (ientry != entry_for_kind(AbstractInterpreter::zerolocals) &&

      ientry != entry_for_kind(AbstractInterpreter::zerolocals_synchronized))

    return false;  // interpreter does not run this method!

  // otherwise, we can be sure this bytecode has never been executed

  return true;

}

#ifndef PRODUCT

void AbstractInterpreter::print_method_kind(MethodKind kind) {

  switch (kind) {

    case zerolocals             : tty->print("zerolocals"             ); break;

    case zerolocals_synchronized: tty->print("zerolocals_synchronized"); break;

    case native                 : tty->print("native"                 ); break;

    case native_synchronized    : tty->print("native_synchronized"    ); break;

    case empty                  : tty->print("empty"                  ); break;

    case accessor               : tty->print("accessor"               ); break;

    case abstract               : tty->print("abstract"               ); break;

    case method_handle          : tty->print("method_handle"          ); break;

    case java_lang_math_sin     : tty->print("java_lang_math_sin"     ); break;

    case java_lang_math_cos     : tty->print("java_lang_math_cos"     ); break;

    case java_lang_math_tan     : tty->print("java_lang_math_tan"     ); break;

    case java_lang_math_abs     : tty->print("java_lang_math_abs"     ); break;

    case java_lang_math_sqrt    : tty->print("java_lang_math_sqrt"    ); break;

    case java_lang_math_log     : tty->print("java_lang_math_log"     ); break;

    case java_lang_math_log10   : tty->print("java_lang_math_log10"   ); break;

    default                     : ShouldNotReachHere();

  }

}

#endif // PRODUCT

//------------------------------------------------------------------------------------------------------------------------

// Deoptimization support

// If deoptimization happens, this function returns the point of next bytecode to continue execution

address AbstractInterpreter::deopt_continue_after_entry(methodOop method, address bcp, int callee_parameters, bool is_top_frame) {

  assert(method->contains(bcp), "just checkin'");

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

  assert(!Interpreter::bytecode_should_reexecute(code), "should not reexecute");

  int             bci    = method->bci_from(bcp);

  int             length = -1; // initial value for debugging

  // compute continuation length

  length = Bytecodes::length_at(bcp);

  // compute result type

  BasicType type = T_ILLEGAL;

  switch (code) {

    case Bytecodes::_invokevirtual  :

    case Bytecodes::_invokespecial  :

    case Bytecodes::_invokestatic   :

    case Bytecodes::_invokeinterface: {

      Thread *thread = Thread::current();

      ResourceMark rm(thread);

      methodHandle mh(thread, method);

      type = Bytecode_invoke_at(mh, bci)->result_type(thread);

      // since the cache entry might not be initialized:

      // (NOT needed for the old calling convension)

      if (!is_top_frame) {

        int index = Bytes::get_native_u2(bcp+1);

        method->constants()->cache()->entry_at(index)->set_parameter_size(callee_parameters);

      }

      break;

    }

   case Bytecodes::_invokedynamic: {

      Thread *thread = Thread::current();

      ResourceMark rm(thread);

      methodHandle mh(thread, method);

      type = Bytecode_invoke_at(mh, bci)->result_type(thread);

      // since the cache entry might not be initialized:

      // (NOT needed for the old calling convension)

      if (!is_top_frame) {

        int index = Bytes::get_native_u4(bcp+1);

        method->constants()->cache()->secondary_entry_at(index)->set_parameter_size(callee_parameters);

      }

      break;

    }

    case Bytecodes::_ldc   :

    case Bytecodes::_ldc_w : // fall through

    case Bytecodes::_ldc2_w:

    default:

      type = Bytecodes::result_type(code);

      break;

  }

  // return entry point for computed continuation state & bytecode length

  return

    is_top_frame

    ? Interpreter::deopt_entry (as_TosState(type), length)

    : Interpreter::return_entry(as_TosState(type), length);

}

// If deoptimization happens, this function returns the point where the interpreter reexecutes

// the bytecode.

// Note: Bytecodes::_athrow is a special case in that it does not return

//       Interpreter::deopt_entry(vtos, 0) like others

address AbstractInterpreter::deopt_reexecute_entry(methodOop method, address bcp) {

  assert(method->contains(bcp), "just checkin'");

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

#ifdef COMPILER1

  if(code == Bytecodes::_athrow ) {

    return Interpreter::rethrow_exception_entry();

  }

#endif /* COMPILER1 */

  return Interpreter::deopt_entry(vtos, 0);

}

// If deoptimization happens, the interpreter should reexecute these bytecodes.

// This function mainly helps the compilers to set up the reexecute bit.

bool AbstractInterpreter::bytecode_should_reexecute(Bytecodes::Code code) {

  switch (code) {

    case Bytecodes::_lookupswitch:

    case Bytecodes::_tableswitch:

    case Bytecodes::_fast_binaryswitch:

    case Bytecodes::_fast_linearswitch:

    // recompute condtional expression folded into _if<cond>

    case Bytecodes::_lcmp      :

    case Bytecodes::_fcmpl     :

    case Bytecodes::_fcmpg     :

    case Bytecodes::_dcmpl     :

    case Bytecodes::_dcmpg     :

    case Bytecodes::_ifnull    :

    case Bytecodes::_ifnonnull :

    case Bytecodes::_goto      :

    case Bytecodes::_goto_w    :

    case Bytecodes::_ifeq      :

    case Bytecodes::_ifne      :

    case Bytecodes::_iflt      :

    case Bytecodes::_ifge      :

    case Bytecodes::_ifgt      :

    case Bytecodes::_ifle      :

    case Bytecodes::_if_icmpeq :

    case Bytecodes::_if_icmpne :

    case Bytecodes::_if_icmplt :

    case Bytecodes::_if_icmpge :

    case Bytecodes::_if_icmpgt :

    case Bytecodes::_if_icmple :

    case Bytecodes::_if_acmpeq :

    case Bytecodes::_if_acmpne :

    // special cases

    case Bytecodes::_getfield  :

    case Bytecodes::_putfield  :

    case Bytecodes::_getstatic :

    case Bytecodes::_putstatic :

    case Bytecodes::_aastore   :

#ifdef COMPILER1

    //special case of reexecution

    case Bytecodes::_athrow    :

#endif

      return true;

    default:

      return false;

  }

}

void AbstractInterpreterGenerator::bang_stack_shadow_pages(bool native_call) {

  // Quick & dirty stack overflow checking: bang the stack & handle trap.

  // Note that we do the banging after the frame is setup, since the exception

  // handling code expects to find a valid interpreter frame on the stack.

  // Doing the banging earlier fails if the caller frame is not an interpreter

  // frame.

  // (Also, the exception throwing code expects to unlock any synchronized

  // method receiever, so do the banging after locking the receiver.)

  // Bang each page in the shadow zone. We can't assume it's been done for

  // an interpreter frame with greater than a page of locals, so each page

  // needs to be checked.  Only true for non-native.

  if (UseStackBanging) {

    const int start_page = native_call ? StackShadowPages : 1;

    const int page_size = os::vm_page_size();

    for (int pages = start_page; pages <= StackShadowPages ; pages++) {

      __ bang_stack_with_offset(pages*page_size);

    }

  }

}