/*

 * Copyright (c) 1997, 2019, 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 "asm/macroAssembler.hpp"

#include "asm/macroAssembler.inline.hpp"

#include "compiler/disassembler.hpp"

#include "interpreter/bytecodeHistogram.hpp"

#include "interpreter/bytecodeInterpreter.hpp"

#include "interpreter/bytecodeStream.hpp"

#include "interpreter/interpreter.hpp"

#include "interpreter/interpreterRuntime.hpp"

#include "interpreter/interp_masm.hpp"

#include "interpreter/templateTable.hpp"

#include "memory/allocation.inline.hpp"

#include "memory/metaspaceShared.hpp"

#include "memory/resourceArea.hpp"

#include "oops/arrayOop.hpp"

#include "oops/constantPool.hpp"

#include "oops/cpCache.inline.hpp"

#include "oops/methodData.hpp"

#include "oops/method.hpp"

#include "oops/oop.inline.hpp"

#include "prims/forte.hpp"

#include "prims/jvmtiExport.hpp"

#include "prims/methodHandles.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/sharedRuntime.hpp"

#include "runtime/stubRoutines.hpp"

#include "runtime/timer.hpp"

# define __ _masm->

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

// 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();

}

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());

  if (_code->number_of_stubs() != 0) {

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

    tty->cr();

  }

  _code->print();

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

  tty->cr();

}

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

// 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::_cds_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;

}

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

// Entry points

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

  // Abstract method?

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

  // Method handle primitive?

  if (m->is_method_handle_intrinsic()) {

    vmIntrinsics::ID id = m->intrinsic_id();

    assert(MethodHandles::is_signature_polymorphic(id), "must match an intrinsic");

    MethodKind kind = (MethodKind)( method_handle_invoke_FIRST +

                                    ((int)id - vmIntrinsics::FIRST_MH_SIG_POLY) );

    assert(kind <= method_handle_invoke_LAST, "parallel enum ranges");

    return kind;

  }

#ifndef CC_INTERP

  switch (m->intrinsic_id()) {

    // Use optimized stub code for CRC32 native methods.

    case vmIntrinsics::_updateCRC32            : return java_util_zip_CRC32_update;

    case vmIntrinsics::_updateBytesCRC32       : return java_util_zip_CRC32_updateBytes;

    case vmIntrinsics::_updateByteBufferCRC32  : return java_util_zip_CRC32_updateByteBuffer;

    // Use optimized stub code for CRC32C methods.

    case vmIntrinsics::_updateBytesCRC32C             : return java_util_zip_CRC32C_updateBytes;

    case vmIntrinsics::_updateDirectByteBufferCRC32C  : return java_util_zip_CRC32C_updateDirectByteBuffer;

    case vmIntrinsics::_intBitsToFloat:      return java_lang_Float_intBitsToFloat;

    case vmIntrinsics::_floatToRawIntBits:   return java_lang_Float_floatToRawIntBits;

    case vmIntrinsics::_longBitsToDouble:    return java_lang_Double_longBitsToDouble;

    case vmIntrinsics::_doubleToRawLongBits: return java_lang_Double_doubleToRawLongBits;

    default:                                 break;

  }

#endif // CC_INTERP

  // 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_intrinsic(), "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;

  }

  // 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

  //       TemplateInterpreterGenerator::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;

    case vmIntrinsics::_dpow  : return java_lang_math_pow  ;

    case vmIntrinsics::_dexp  : return java_lang_math_exp  ;

    case vmIntrinsics::_fmaD  : return java_lang_math_fmaD ;

    case vmIntrinsics::_fmaF  : return java_lang_math_fmaF ;

    case vmIntrinsics::_Reference_get

                              : return java_lang_ref_reference_get;

    default                   : break;

  }

  // Accessor method?

  if (m->is_getter()) {

    // TODO: We should have used ::is_accessor above, but fast accessors in Zero expect only getters.

    // See CppInterpreter::accessor_entry in cppInterpreter_zero.cpp. This should be fixed in Zero,

    // then the call above updated to ::is_accessor

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

    return accessor;

  }

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

  return zerolocals;

}

#if INCLUDE_CDS

address AbstractInterpreter::get_trampoline_code_buffer(AbstractInterpreter::MethodKind kind) {

  const size_t trampoline_size = SharedRuntime::trampoline_size();

  address addr = MetaspaceShared::i2i_entry_code_buffers((size_t)(AbstractInterpreter::number_of_method_entries) * trampoline_size);

  addr += (size_t)(kind) * trampoline_size;

  return addr;

}

void AbstractInterpreter::update_cds_entry_table(AbstractInterpreter::MethodKind kind) {

  if (DumpSharedSpaces || UseSharedSpaces) {

    address trampoline = get_trampoline_code_buffer(kind);

    _cds_entry_table[kind] = trampoline;

    CodeBuffer buffer(trampoline, (int)(SharedRuntime::trampoline_size()));

    MacroAssembler _masm(&buffer);

    SharedRuntime::generate_trampoline(&_masm, _entry_table[kind]);

    if (PrintInterpreter) {

      Disassembler::decode(buffer.insts_begin(), buffer.insts_end());

    }

  }

}

#endif

void AbstractInterpreter::set_entry_for_kind(AbstractInterpreter::MethodKind kind, address entry) {

  assert(kind >= method_handle_invoke_FIRST &&

         kind <= method_handle_invoke_LAST, "late initialization only for MH entry points");

  assert(_entry_table[kind] == _entry_table[abstract], "previous value must be AME entry");

  _entry_table[kind] = entry;

  update_cds_entry_table(kind);

}

// 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(const methodHandle& method, int bci) {

  BytecodeStream s(method, bci);

  Bytecodes::Code code = s.next();

  if (Bytecodes::is_invoke(code)) {

    assert(!Bytecodes::must_rewrite(code), "invokes aren't rewritten");

    ConstantPool* cpool = method()->constants();

    Bytecode invoke_bc(s.bytecode());

    switch (code) {

      case Bytecodes::_invokedynamic: {

        assert(invoke_bc.has_index_u4(code), "sanity");

        int method_index = invoke_bc.get_index_u4(code);

        return cpool->invokedynamic_cp_cache_entry_at(method_index)->is_f1_null();

      }

      case Bytecodes::_invokevirtual:   // fall-through

      case Bytecodes::_invokeinterface: // fall-through

      case Bytecodes::_invokespecial:   // fall-through

      case Bytecodes::_invokestatic: {

        if (cpool->has_preresolution()) {

          return false; // might have been reached

        }

        assert(!invoke_bc.has_index_u4(code), "sanity");

        int method_index = invoke_bc.get_index_u2_cpcache(code);

        return (resolved_method == NULL);

      }

      default: ShouldNotReachHere();

    }

  } else if (!Bytecodes::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 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;

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

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

    case java_util_zip_CRC32_update           : tty->print("java_util_zip_CRC32_update"); break;

    case java_util_zip_CRC32_updateBytes      : tty->print("java_util_zip_CRC32_updateBytes"); break;

    case java_util_zip_CRC32_updateByteBuffer : tty->print("java_util_zip_CRC32_updateByteBuffer"); break;

    case java_util_zip_CRC32C_updateBytes     : tty->print("java_util_zip_CRC32C_updateBytes"); break;

    case java_util_zip_CRC32C_updateDirectByteBuffer: tty->print("java_util_zip_CRC32C_updateDirectByteByffer"); break;

    default:

      if (kind >= method_handle_invoke_FIRST &&

          kind <= method_handle_invoke_LAST) {

        const char* kind_name = vmIntrinsics::name_at(method_handle_intrinsic(kind));

        if (kind_name[0] == '_')  kind_name = &kind_name[1];  // '_invokeExact' => 'invokeExact'

        tty->print("method_handle_%s", kind_name);

        break;

      }

      ShouldNotReachHere();

      break;

  }

}

#endif // PRODUCT

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

// Deoptimization support

/**

 * If a deoptimization happens, this function returns the point of next bytecode to continue execution.

 */

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

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

  // Get the original and rewritten bytecode.

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

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

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

  // compute continuation length

  const int length = Bytecodes::length_at(method, 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(mh, bci).result_type();

      // 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(mh, bci).result_type();

      // 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()->invokedynamic_cp_cache_entry_at(index)->set_parameter_size(callee_parameters);

      }

      break;

    }

    case Bytecodes::_ldc   :

    case Bytecodes::_ldc_w : // fall through

    case Bytecodes::_ldc2_w:

      {

        Thread *thread = Thread::current();

        ResourceMark rm(thread);

        methodHandle mh(thread, method);

        type = Bytecode_loadconstant(mh, bci).result_type();

        break;

      }

    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, code);

}

// 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(Method* method, address bcp) {

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

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

#if defined(COMPILER1) || INCLUDE_JVMCI

  if(code == Bytecodes::_athrow ) {

    return Interpreter::rethrow_exception_entry();

  }

#endif /* COMPILER1 || INCLUDE_JVMCI */

  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 AbstractInterpreter::initialize_method_handle_entries() {

  // method handle entry kinds are generated later in MethodHandlesAdapterGenerator::generate:

  for (int i = method_handle_invoke_FIRST; i <= method_handle_invoke_LAST; i++) {

    MethodKind kind = (MethodKind) i;

    _entry_table[kind] = _entry_table[Interpreter::abstract];

    Interpreter::update_cds_entry_table(kind);

  }

}