/*

 * 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 "classfile/javaClasses.inline.hpp"

#include "interpreter/bytecodeHistogram.hpp"

#include "interpreter/bytecodeTracer.hpp"

#include "interpreter/bytecodes.hpp"

#include "interpreter/interpreter.hpp"

#include "interpreter/interpreterRuntime.hpp"

#include "memory/resourceArea.hpp"

#include "oops/constantPool.inline.hpp"

#include "oops/methodData.hpp"

#include "oops/method.hpp"

#include "runtime/mutexLocker.hpp"

#include "runtime/timer.hpp"

#include "utilities/align.hpp"

// Standard closure for BytecodeTracer: prints the current bytecode

// and its attributes using bytecode-specific information.

class BytecodePrinter: public BytecodeClosure {

 private:

  // %%% This field is not GC-ed, and so can contain garbage

  // between critical sections.  Use only pointer-comparison

  // operations on the pointer, except within a critical section.

  // (Also, ensure that occasional false positives are benign.)

  Method* _current_method;

  bool      _is_wide;

  Bytecodes::Code _code;

  address   _next_pc;                // current decoding position

  void      align()                  { _next_pc = align_up(_next_pc, sizeof(jint)); }

  int       get_byte()               { return *(jbyte*) _next_pc++; }  // signed

  short     get_short()              { short i=Bytes::get_Java_u2(_next_pc); _next_pc+=2; return i; }

  int       get_int()                { int i=Bytes::get_Java_u4(_next_pc); _next_pc+=4; return i; }

  int       get_index_u1()           { return *(address)_next_pc++; }

  int       get_index_u2()           { int i=Bytes::get_Java_u2(_next_pc); _next_pc+=2; return i; }

  int       get_index_u1_cpcache()   { return get_index_u1() + ConstantPool::CPCACHE_INDEX_TAG; }

  int       get_index_u2_cpcache()   { int i=Bytes::get_native_u2(_next_pc); _next_pc+=2; return i + ConstantPool::CPCACHE_INDEX_TAG; }

  int       get_index_u4()           { int i=Bytes::get_native_u4(_next_pc); _next_pc+=4; return i; }

  int       get_index_special()      { return (is_wide()) ? get_index_u2() : get_index_u1(); }

  Method* method()                 { return _current_method; }

  bool      is_wide()                { return _is_wide; }

  Bytecodes::Code raw_code()         { return Bytecodes::Code(_code); }

  bool      check_index(int i, int& cp_index, outputStream* st = tty);

  bool      check_cp_cache_index(int i, int& cp_index, outputStream* st = tty);

  bool      check_obj_index(int i, int& cp_index, outputStream* st = tty);

  bool      check_invokedynamic_index(int i, int& cp_index, outputStream* st = tty);

  void      print_constant(int i, outputStream* st = tty);

  void      print_field_or_method(int i, outputStream* st = tty);

  void      print_field_or_method(int orig_i, int i, outputStream* st = tty);

  void      print_attributes(int bci, outputStream* st = tty);

  void      bytecode_epilog(int bci, outputStream* st = tty);

 public:

  BytecodePrinter() {

    _is_wide = false;

    _code = Bytecodes::_illegal;

  }

  // This method is called while executing the raw bytecodes, so none of

  // the adjustments that BytecodeStream performs applies.

  void trace(const methodHandle& method, address bcp, uintptr_t tos, uintptr_t tos2, outputStream* st) {

    ResourceMark rm;

    if (_current_method != method()) {

      // Note 1: This code will not work as expected with true MT/MP.

      //         Need an explicit lock or a different solution.

      // It is possible for this block to be skipped, if a garbage

      // _current_method pointer happens to have the same bits as

      // the incoming method.  We could lose a line of trace output.

      // This is acceptable in a debug-only feature.

      st->cr();

      st->print("[%ld] ", (long) Thread::current()->osthread()->thread_id());

      method->print_name(st);

      st->cr();

      _current_method = method();

    }

    Bytecodes::Code code;

    if (is_wide()) {

      // bcp wasn't advanced if previous bytecode was _wide.

      code = Bytecodes::code_at(method(), bcp+1);

    } else {

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

    }

    _code = code;

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

    st->print("[%ld] ", (long) Thread::current()->osthread()->thread_id());

    if (Verbose) {

      st->print("%8d  %4d  " INTPTR_FORMAT " " INTPTR_FORMAT " %s",

           BytecodeCounter::counter_value(), bci, tos, tos2, Bytecodes::name(code));

    } else {

      st->print("%8d  %4d  %s",

           BytecodeCounter::counter_value(), bci, Bytecodes::name(code));

    }

    _next_pc = is_wide() ? bcp+2 : bcp+1;

    print_attributes(bci);

    // Set is_wide for the next one, since the caller of this doesn't skip

    // the next bytecode.

    _is_wide = (code == Bytecodes::_wide);

    _code = Bytecodes::_illegal;

  }

  // Used for Method*::print_codes().  The input bcp comes from

  // BytecodeStream, which will skip wide bytecodes.

  void trace(const methodHandle& method, address bcp, outputStream* st) {

    _current_method = method();

    ResourceMark rm;

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

    // Set is_wide

    _is_wide = (code == Bytecodes::_wide);

    if (is_wide()) {

      code = Bytecodes::code_at(method(), bcp+1);

    }

    _code = code;

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

    // Print bytecode index and name

    if (is_wide()) {

      st->print("%d %s_w", bci, Bytecodes::name(code));

    } else {

      st->print("%d %s", bci, Bytecodes::name(code));

    }

    _next_pc = is_wide() ? bcp+2 : bcp+1;

    print_attributes(bci, st);

    bytecode_epilog(bci, st);

  }

};

// Implementation of BytecodeTracer

// %%% This set_closure thing seems overly general, given that

// nobody uses it.  Also, if BytecodePrinter weren't hidden

// then Method* could use instances of it directly and it

// would be easier to remove races on _current_method and bcp.

// Since this is not product functionality, we can defer cleanup.

BytecodeClosure* BytecodeTracer::_closure = NULL;

static BytecodePrinter std_closure;

BytecodeClosure* BytecodeTracer::std_closure() {

  return &::std_closure;

}

void BytecodeTracer::trace(const methodHandle& method, address bcp, uintptr_t tos, uintptr_t tos2, outputStream* st) {

  if (TraceBytecodes && BytecodeCounter::counter_value() >= TraceBytecodesAt) {

    ttyLocker ttyl;  // 5065316: keep the following output coherent

    // The ttyLocker also prevents races between two threads

    // trying to use the single instance of BytecodePrinter.

    // Using the ttyLocker prevents the system from coming to

    // a safepoint within this code, which is sensitive to Method*

    // movement.

    //

    // There used to be a leaf mutex here, but the ttyLocker will

    // work just as well, as long as the printing operations never block.

    //

    // We put the locker on the static trace method, not the

    // virtual one, because the clients of this module go through

    // the static method.

    _closure->trace(method, bcp, tos, tos2, st);

  }

}

void BytecodeTracer::trace(const methodHandle& method, address bcp, outputStream* st) {

  ttyLocker ttyl;  // 5065316: keep the following output coherent

  _closure->trace(method, bcp, st);

}

void print_symbol(Symbol* sym, outputStream* st) {

  char buf[40];

  int len = sym->utf8_length();

  if (len >= (int)sizeof(buf)) {

    st->print_cr(" %s...[%d]", sym->as_C_string(buf, sizeof(buf)), len);

  } else {

    st->print(" ");

    sym->print_on(st); st->cr();

  }

}

void print_oop(oop value, outputStream* st) {

  if (value == NULL) {

    st->print_cr(" NULL");

  } else if (java_lang_String::is_instance(value)) {

    char buf[40];

    int len = java_lang_String::utf8_length(value);

    java_lang_String::as_utf8_string(value, buf, sizeof(buf));

    if (len >= (int)sizeof(buf)) {

      st->print_cr(" %s...[%d]", buf, len);

    } else {

      st->print_cr(" %s", buf);

    }

  } else {

    st->print_cr(" " INTPTR_FORMAT, p2i((void *)value));

  }

}

bool BytecodePrinter::check_index(int i, int& cp_index, outputStream* st) {

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

  int ilimit = constants->length();

  Bytecodes::Code code = raw_code();

  if (Bytecodes::uses_cp_cache(code)) {

    bool okay = true;

    switch (code) {

    case Bytecodes::_fast_aldc:

    case Bytecodes::_fast_aldc_w:

      okay = check_obj_index(i, cp_index, st);

      break;

    case Bytecodes::_invokedynamic:

      okay = check_invokedynamic_index(i, cp_index, st);

      break;

    default:

      okay = check_cp_cache_index(i, cp_index, st);

      break;

    }

    if (!okay) return false;

  }

  // check cp index

  if (cp_index >= 0 && cp_index < ilimit) {

    if (WizardMode)  st->print(" cp[%d]", cp_index);

    return true;

  }

  st->print_cr(" CP[%d] not in CP", cp_index);

  return false;

}

bool BytecodePrinter::check_cp_cache_index(int i, int& cp_index, outputStream* st) {

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

  int climit = 0;

  ConstantPoolCache* cache = constants->cache();

  // If rewriter hasn't run, the index is the cp_index

  if (cache == NULL) {

    cp_index = i;

    return true;

  }

  //climit = cache->length();  // %%% private!

  size_t size = cache->size() * wordSize;

  size -= sizeof(ConstantPoolCache);

  size /= sizeof(ConstantPoolCacheEntry);

  climit = (int) size;

#ifdef ASSERT

  {

    const int CPCACHE_INDEX_TAG = ConstantPool::CPCACHE_INDEX_TAG;

    if (i >= CPCACHE_INDEX_TAG && i < climit + CPCACHE_INDEX_TAG) {

      i -= CPCACHE_INDEX_TAG;

    } else {

      st->print_cr(" CP[%d] missing bias?", i);

      return false;

    }

  }

#endif //ASSERT

  if (i >= 0 && i < climit) {

    cp_index = cache->entry_at(i)->constant_pool_index();

  } else {

    st->print_cr("%d not in CP[*]?", i);

      return false;

    }

  return true;

  }

bool BytecodePrinter::check_obj_index(int i, int& cp_index, outputStream* st) {

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

  i -= ConstantPool::CPCACHE_INDEX_TAG;

  if (i >= 0 && i < constants->resolved_references()->length()) {

     cp_index = constants->object_to_cp_index(i);

     return true;

  } else {

    st->print_cr("%d not in OBJ[*]?", i);

  return false;

}

}

bool BytecodePrinter::check_invokedynamic_index(int i, int& cp_index, outputStream* st) {

  assert(ConstantPool::is_invokedynamic_index(i), "not secondary index?");

  i = ConstantPool::decode_invokedynamic_index(i) + ConstantPool::CPCACHE_INDEX_TAG;

  return check_cp_cache_index(i, cp_index, st);

}

void BytecodePrinter::print_constant(int i, outputStream* st) {

  int orig_i = i;

  if (!check_index(orig_i, i, st))  return;

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

  constantTag tag = constants->tag_at(i);

  if (tag.is_int()) {

    st->print_cr(" " INT32_FORMAT, constants->int_at(i));

  } else if (tag.is_long()) {

    st->print_cr(" " INT64_FORMAT, (int64_t)(constants->long_at(i)));

  } else if (tag.is_float()) {

    st->print_cr(" %f", constants->float_at(i));

  } else if (tag.is_double()) {

    st->print_cr(" %f", constants->double_at(i));

  } else if (tag.is_string()) {

    const char* string = constants->string_at_noresolve(i);

    st->print_cr(" %s", string);

  } else if (tag.is_klass()) {

    st->print_cr(" %s", constants->resolved_klass_at(i)->external_name());

  } else if (tag.is_unresolved_klass()) {

    st->print_cr(" <unresolved klass at %d>", i);

  } else if (tag.is_method_type()) {

    int i2 = constants->method_type_index_at(i);

    st->print(" <MethodType> %d", i2);

    print_symbol(constants->symbol_at(i2), st);

  } else if (tag.is_method_handle()) {

    int kind = constants->method_handle_ref_kind_at(i);

    int i2 = constants->method_handle_index_at(i);

    st->print(" <MethodHandle of kind %d index at %d>", kind, i2);

    print_field_or_method(-i, i2, st);

  } else {

    st->print_cr(" bad tag=%d at %d", tag.value(), i);

  }

}

void BytecodePrinter::print_field_or_method(int i, outputStream* st) {

  int orig_i = i;

  if (!check_index(orig_i, i, st))  return;

  print_field_or_method(orig_i, i, st);

}

void BytecodePrinter::print_field_or_method(int orig_i, int i, outputStream* st) {

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

  constantTag tag = constants->tag_at(i);

  bool has_klass = true;

  switch (tag.value()) {

  case JVM_CONSTANT_InterfaceMethodref:

  case JVM_CONSTANT_Methodref:

  case JVM_CONSTANT_Fieldref:

    break;

  case JVM_CONSTANT_NameAndType:

  case JVM_CONSTANT_Dynamic:

  case JVM_CONSTANT_InvokeDynamic:

    has_klass = false;

    break;

  default:

    st->print_cr(" bad tag=%d at %d", tag.value(), i);

    return;

  }

  Symbol* name = constants->uncached_name_ref_at(i);

  Symbol* signature = constants->uncached_signature_ref_at(i);

  const char* sep = (tag.is_field() ? "/" : "");

  if (has_klass) {

    Symbol* klass = constants->klass_name_at(constants->uncached_klass_ref_index_at(i));

    st->print_cr(" %d <%s.%s%s%s> ", i, klass->as_C_string(), name->as_C_string(), sep, signature->as_C_string());

  } else {

    if (tag.is_dynamic_constant() || tag.is_invoke_dynamic()) {

      int bsm = constants->bootstrap_method_ref_index_at(i);

      st->print(" bsm=%d", bsm);

    }

    st->print_cr(" %d <%s%s%s>", i, name->as_C_string(), sep, signature->as_C_string());

  }

}

void BytecodePrinter::print_attributes(int bci, outputStream* st) {

  // Show attributes of pre-rewritten codes

  Bytecodes::Code code = Bytecodes::java_code(raw_code());

  // If the code doesn't have any fields there's nothing to print.

  // note this is ==1 because the tableswitch and lookupswitch are

  // zero size (for some reason) and we want to print stuff out for them.

  if (Bytecodes::length_for(code) == 1) {

    st->cr();

    return;

  }

  switch(code) {

    // Java specific bytecodes only matter.

    case Bytecodes::_bipush:

      st->print_cr(" " INT32_FORMAT, get_byte());

      break;

    case Bytecodes::_sipush:

      st->print_cr(" " INT32_FORMAT, get_short());

      break;

    case Bytecodes::_ldc:

      if (Bytecodes::uses_cp_cache(raw_code())) {

        print_constant(get_index_u1_cpcache(), st);

      } else {

        print_constant(get_index_u1(), st);

      }

      break;

    case Bytecodes::_ldc_w:

    case Bytecodes::_ldc2_w:

      if (Bytecodes::uses_cp_cache(raw_code())) {

        print_constant(get_index_u2_cpcache(), st);

      } else {

        print_constant(get_index_u2(), st);

      }

      break;

    case Bytecodes::_iload:

    case Bytecodes::_lload:

    case Bytecodes::_fload:

    case Bytecodes::_dload:

    case Bytecodes::_aload:

    case Bytecodes::_istore:

    case Bytecodes::_lstore:

    case Bytecodes::_fstore:

    case Bytecodes::_dstore:

    case Bytecodes::_astore:

      st->print_cr(" #%d", get_index_special());

      break;

    case Bytecodes::_iinc:

      { int index = get_index_special();

        jint offset = is_wide() ? get_short(): get_byte();

        st->print_cr(" #%d " INT32_FORMAT, index, offset);

      }

      break;

    case Bytecodes::_newarray: {

        BasicType atype = (BasicType)get_index_u1();

        const char* str = type2name(atype);

          assert(false, "Unidentified basic type");

        }

        st->print_cr(" %s", str);

      }

      break;

    case Bytecodes::_anewarray: {

        int klass_index = get_index_u2();

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

        Symbol* name = constants->klass_name_at(klass_index);

        st->print_cr(" %s ", name->as_C_string());

      }

      break;

    case Bytecodes::_multianewarray: {

        int klass_index = get_index_u2();

        int nof_dims = get_index_u1();

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

        Symbol* name = constants->klass_name_at(klass_index);

        st->print_cr(" %s %d", name->as_C_string(), nof_dims);

      }

      break;

    case Bytecodes::_ifeq:

    case Bytecodes::_ifnull:

    case Bytecodes::_iflt:

    case Bytecodes::_ifle:

    case Bytecodes::_ifne:

    case Bytecodes::_ifnonnull:

    case Bytecodes::_ifgt:

    case Bytecodes::_ifge:

    case Bytecodes::_if_icmpeq:

    case Bytecodes::_if_icmpne:

    case Bytecodes::_if_icmplt:

    case Bytecodes::_if_icmpgt:

    case Bytecodes::_if_icmple:

    case Bytecodes::_if_icmpge:

    case Bytecodes::_if_acmpeq:

    case Bytecodes::_if_acmpne:

    case Bytecodes::_goto:

    case Bytecodes::_jsr:

      st->print_cr(" %d", bci + get_short());

      break;

    case Bytecodes::_goto_w:

    case Bytecodes::_jsr_w:

      st->print_cr(" %d", bci + get_int());

      break;

    case Bytecodes::_ret: st->print_cr(" %d", get_index_special()); break;