text: /*
   * 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 "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/methodDataOop.hpp"
  #include "oops/methodOop.hpp"
  #include "runtime/mutexLocker.hpp"
  #include "runtime/timer.hpp"
  
  
  #ifndef PRODUCT
  
  // 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.)
    methodOop _current_method;
    bool      _is_wide;
    Bytecodes::Code _code;
    address   _next_pc;                // current decoding position
  
    void      align()                  { _next_pc = (address)round_to((intptr_t)_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() + constantPoolOopDesc::CPCACHE_INDEX_TAG; }
    int       get_index_u2_cpcache()   { int i=Bytes::get_native_u2(_next_pc); _next_pc+=2; return i + constantPoolOopDesc::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(); }
    methodOop 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);
    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(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 methodOop::print_codes().  The input bcp comes from
    // BytecodeStream, which will skip wide bytecodes.
    void trace(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 methodOop 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(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 methodOop
      // 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(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(" " PTR_FORMAT, (intptr_t) value);
    }
  }
  
  bool BytecodePrinter::check_index(int i, int& cp_index, outputStream* st) {
    constantPoolOop constants = method()->constants();
    int ilimit = constants->length(), climit = 0;
    Bytecodes::Code code = raw_code();
  
    constantPoolCacheOop cache = NULL;
    if (Bytecodes::uses_cp_cache(code)) {
      cache = constants->cache();
      if (cache != NULL) {
        //climit = cache->length();  // %%% private!
        size_t size = cache->size() * HeapWordSize;
        size -= sizeof(constantPoolCacheOopDesc);
        size /= sizeof(ConstantPoolCacheEntry);
        climit = (int) size;
      }
    }
  
    if (cache != NULL && constantPoolCacheOopDesc::is_secondary_index(i)) {
      i = constantPoolCacheOopDesc::decode_secondary_index(i);
      st->print(" secondary cache[%d] of", i);
      if (i >= 0 && i < climit) {
        if (!cache->entry_at(i)->is_secondary_entry()) {
          st->print_cr(" not secondary entry?", i);
          return false;
        }
        i = cache->entry_at(i)->main_entry_index() + constantPoolOopDesc::CPCACHE_INDEX_TAG;
        goto check_cache_index;
      } else {
        st->print_cr(" not in cache[*]?", i);
        return false;
      }
    }
  
    if (cache != NULL) {
      goto check_cache_index;
    }
  
   check_cp_index:
    if (i >= 0 && i < ilimit) {
      if (WizardMode)  st->print(" cp[%d]", i);
      cp_index = i;
      return true;
    }
  
    st->print_cr(" CP[%d] not in CP", i);
    return false;
  
   check_cache_index:
  #ifdef ASSERT
    {
      const int CPCACHE_INDEX_TAG = constantPoolOopDesc::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) {
      if (cache->entry_at(i)->is_secondary_entry()) {
        st->print_cr(" secondary entry?");
        return false;
      }
      i = cache->entry_at(i)->constant_pool_index();
      goto check_cp_index;
    }
    st->print_cr(" not in CP[*]?", i);
    return false;
  }
  
  void BytecodePrinter::print_constant(int i, outputStream* st) {
    int orig_i = i;
    if (!check_index(orig_i, i, st))  return;
  
    constantPoolOop 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, 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()) {
      oop string = constants->pseudo_string_at(i);
      print_oop(string, st);
    } else if (tag.is_unresolved_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)->klass_part()->external_name());
    } else if (tag.is_unresolved_klass()) {
      st->print_cr(" <unresolved klass at %d>", i);
    } else if (tag.is_object()) {
      st->print(" <Object>");
      print_oop(constants->object_at(i), st);
    } 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>", 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) {
    constantPoolOop 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_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_invoke_dynamic()) {
        int bsm = constants->invoke_dynamic_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);
          if (str == NULL || atype == T_OBJECT || atype == T_ARRAY) {
            assert(false, "Unidentified basic type");
          }
          st->print_cr(" %s", str);
        }
        break;
      case Bytecodes::_anewarray: {
          int klass_index = get_index_u2();
          constantPoolOop 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();
          constantPoolOop 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;
  
      case Bytecodes::_tableswitch:
        { align();
          int  default_dest = bci + get_int();
          int  lo           = get_int();
          int  hi           = get_int();
          int  len          = hi - lo + 1;
          jint* dest        = NEW_RESOURCE_ARRAY(jint, len);
          for (int i = 0; i < len; i++) {
            dest[i] = bci + get_int();
          }
          st->print(" %d " INT32_FORMAT " " INT32_FORMAT " ",
                        default_dest, lo, hi);
          int first = true;
          for (int ll = lo; ll <= hi; ll++, first = false)  {
            int idx = ll - lo;
            const char *format = first ? " %d:" INT32_FORMAT " (delta: %d)" :
                                         ", %d:" INT32_FORMAT " (delta: %d)";
            st->print(format, ll, dest[idx], dest[idx]-bci);
          }
          st->cr();
        }
        break;
      case Bytecodes::_lookupswitch:
        { align();
          int  default_dest = bci + get_int();
          int  len          = get_int();
          jint* key         = NEW_RESOURCE_ARRAY(jint, len);
          jint* dest        = NEW_RESOURCE_ARRAY(jint, len);
          for (int i = 0; i < len; i++) {
            key [i] = get_int();
            dest[i] = bci + get_int();
          };
          st->print(" %d %d ", default_dest, len);
          bool first = true;
          for (int ll = 0; ll < len; ll++, first = false)  {
            const char *format = first ? " " INT32_FORMAT ":" INT32_FORMAT :
                                         ", " INT32_FORMAT ":" INT32_FORMAT ;
            st->print(format, key[ll], dest[ll]);
          }
          st->cr();
        }
        break;
  
      case Bytecodes::_putstatic:
      case Bytecodes::_getstatic:
      case Bytecodes::_putfield:
      case Bytecodes::_getfield:
        print_field_or_method(get_index_u2_cpcache(), st);
        break;
  
      case Bytecodes::_invokevirtual:
      case Bytecodes::_invokespecial:
      case Bytecodes::_invokestatic:
        print_field_or_method(get_index_u2_cpcache(), st);
        break;
  
      case Bytecodes::_invokeinterface:
        { int i = get_index_u2_cpcache();
          int n = get_index_u1();
          get_byte();            // ignore zero byte
          print_field_or_method(i, st);
        }
        break;
  
      case Bytecodes::_invokedynamic:
        print_field_or_method(get_index_u4(), st);
        break;
  
      case Bytecodes::_new:
      case Bytecodes::_checkcast:
      case Bytecodes::_instanceof:
        { int i = get_index_u2();
          constantPoolOop constants = method()->constants();
          Symbol* name = constants->klass_name_at(i);
          st->print_cr(" %d <%s>", i, name->as_C_string());
        }
        break;
  
      case Bytecodes::_wide:
        // length is zero not one, but printed with no more info.
        break;
  
      default:
        ShouldNotReachHere();
        break;
    }
  }
  
  
  void BytecodePrinter::bytecode_epilog(int bci, outputStream* st) {
    methodDataOop mdo = method()->method_data();
    if (mdo != NULL) {
      ProfileData* data = mdo->bci_to_data(bci);
      if (data != NULL) {
        st->print("  %d", mdo->dp_to_di(data->dp()));
        st->fill_to(6);
        data->print_data_on(st);
      }
    }
  }
  #endif // PRODUCT
  