1 /*
   2  * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 #include "incls/_precompiled.incl"
  26 #include "incls/_bytecodeTracer.cpp.incl"
  27 
  28 
  29 #ifndef PRODUCT
  30 
  31 // Standard closure for BytecodeTracer: prints the current bytecode
  32 // and its attributes using bytecode-specific information.
  33 
  34 class BytecodePrinter: public BytecodeClosure {
  35  private:
  36   // %%% This field is not GC-ed, and so can contain garbage
  37   // between critical sections.  Use only pointer-comparison
  38   // operations on the pointer, except within a critical section.
  39   // (Also, ensure that occasional false positives are benign.)
  40   methodOop _current_method;
  41   bool      _is_wide;
  42   address   _next_pc;                // current decoding position
  43 
  44   void      align()                  { _next_pc = (address)round_to((intptr_t)_next_pc, sizeof(jint)); }
  45   int       get_byte()               { return *(jbyte*) _next_pc++; }  // signed
  46   short     get_short()              { short i=Bytes::get_Java_u2(_next_pc); _next_pc+=2; return i; }
  47   int       get_int()                { int i=Bytes::get_Java_u4(_next_pc); _next_pc+=4; return i; }
  48 
  49   int       get_index()              { return *(address)_next_pc++; }
  50   int       get_big_index()          { int i=Bytes::get_Java_u2(_next_pc); _next_pc+=2; return i; }
  51   int       get_giant_index()        { int i=Bytes::get_native_u4(_next_pc); _next_pc+=4; return i; }
  52   int       get_index_special()      { return (is_wide()) ? get_big_index() : get_index(); }
  53   methodOop method()                 { return _current_method; }
  54   bool      is_wide()                { return _is_wide; }
  55 
  56 
  57   bool      check_index(int i, bool in_cp_cache, int& cp_index, outputStream* st = tty);
  58   void      print_constant(int i, outputStream* st = tty);
  59   void      print_field_or_method(int i, outputStream* st = tty);
  60   void      print_attributes(Bytecodes::Code code, int bci, outputStream* st = tty);
  61   void      bytecode_epilog(int bci, outputStream* st = tty);
  62 
  63  public:
  64   BytecodePrinter() {
  65     _is_wide = false;
  66   }
  67 
  68   // This method is called while executing the raw bytecodes, so none of
  69   // the adjustments that BytecodeStream performs applies.
  70   void trace(methodHandle method, address bcp, uintptr_t tos, uintptr_t tos2, outputStream* st) {
  71     ResourceMark rm;
  72     if (_current_method != method()) {
  73       // Note 1: This code will not work as expected with true MT/MP.
  74       //         Need an explicit lock or a different solution.
  75       // It is possible for this block to be skipped, if a garbage
  76       // _current_method pointer happens to have the same bits as
  77       // the incoming method.  We could lose a line of trace output.
  78       // This is acceptable in a debug-only feature.
  79       st->cr();
  80       st->print("[%d] ", (int) Thread::current()->osthread()->thread_id());
  81       method->print_name(st);
  82       st->cr();
  83       _current_method = method();
  84     }
  85     Bytecodes::Code code;
  86     if (is_wide()) {
  87       // bcp wasn't advanced if previous bytecode was _wide.
  88       code = Bytecodes::code_at(bcp+1);
  89     } else {
  90       code = Bytecodes::code_at(bcp);
  91     }
  92     int bci = bcp - method->code_base();
  93     st->print("[%d] ", (int) Thread::current()->osthread()->thread_id());
  94     if (Verbose) {
  95       st->print("%8d  %4d  " INTPTR_FORMAT " " INTPTR_FORMAT " %s",
  96            BytecodeCounter::counter_value(), bci, tos, tos2, Bytecodes::name(code));
  97     } else {
  98       st->print("%8d  %4d  %s",
  99            BytecodeCounter::counter_value(), bci, Bytecodes::name(code));
 100     }
 101     _next_pc = is_wide() ? bcp+2 : bcp+1;
 102     print_attributes(code, bci);
 103     // Set is_wide for the next one, since the caller of this doesn't skip
 104     // the next bytecode.
 105     _is_wide = (code == Bytecodes::_wide);
 106   }
 107 
 108   // Used for methodOop::print_codes().  The input bcp comes from
 109   // BytecodeStream, which will skip wide bytecodes.
 110   void trace(methodHandle method, address bcp, outputStream* st) {
 111     _current_method = method();
 112     ResourceMark rm;
 113     Bytecodes::Code code = Bytecodes::code_at(bcp);
 114     // Set is_wide
 115     _is_wide = (code == Bytecodes::_wide);
 116     if (is_wide()) {
 117       code = Bytecodes::code_at(bcp+1);
 118     }
 119     int bci = bcp - method->code_base();
 120     // Print bytecode index and name
 121     if (is_wide()) {
 122       st->print("%d %s_w", bci, Bytecodes::name(code));
 123     } else {
 124       st->print("%d %s", bci, Bytecodes::name(code));
 125     }
 126     _next_pc = is_wide() ? bcp+2 : bcp+1;
 127     print_attributes(code, bci, st);
 128     bytecode_epilog(bci, st);
 129   }
 130 };
 131 
 132 
 133 // Implementation of BytecodeTracer
 134 
 135 // %%% This set_closure thing seems overly general, given that
 136 // nobody uses it.  Also, if BytecodePrinter weren't hidden
 137 // then methodOop could use instances of it directly and it
 138 // would be easier to remove races on _current_method and bcp.
 139 // Since this is not product functionality, we can defer cleanup.
 140 
 141 BytecodeClosure* BytecodeTracer::_closure = NULL;
 142 
 143 static BytecodePrinter std_closure;
 144 BytecodeClosure* BytecodeTracer::std_closure() {
 145   return &::std_closure;
 146 }
 147 
 148 
 149 void BytecodeTracer::trace(methodHandle method, address bcp, uintptr_t tos, uintptr_t tos2, outputStream* st) {
 150   if (TraceBytecodes && BytecodeCounter::counter_value() >= TraceBytecodesAt) {
 151     ttyLocker ttyl;  // 5065316: keep the following output coherent
 152     // The ttyLocker also prevents races between two threads
 153     // trying to use the single instance of BytecodePrinter.
 154     // Using the ttyLocker prevents the system from coming to
 155     // a safepoint within this code, which is sensitive to methodOop
 156     // movement.
 157     //
 158     // There used to be a leaf mutex here, but the ttyLocker will
 159     // work just as well, as long as the printing operations never block.
 160     //
 161     // We put the locker on the static trace method, not the
 162     // virtual one, because the clients of this module go through
 163     // the static method.
 164     _closure->trace(method, bcp, tos, tos2, st);
 165   }
 166 }
 167 
 168 void BytecodeTracer::trace(methodHandle method, address bcp, outputStream* st) {
 169   ttyLocker ttyl;  // 5065316: keep the following output coherent
 170   _closure->trace(method, bcp, st);
 171 }
 172 
 173 void print_oop(oop value, outputStream* st) {
 174   if (value == NULL) {
 175     st->print_cr(" NULL");
 176   } else {
 177     EXCEPTION_MARK;
 178     Handle h_value (THREAD, value);
 179     symbolHandle sym = java_lang_String::as_symbol(h_value, CATCH);
 180     if (sym->utf8_length() > 32) {
 181       st->print_cr(" ....");
 182     } else {
 183       sym->print_on(st); st->cr();
 184     }
 185   }
 186 }
 187 
 188 bool BytecodePrinter::check_index(int i, bool in_cp_cache, int& cp_index, outputStream* st) {
 189   constantPoolOop constants = method()->constants();
 190   int ilimit = constants->length(), climit = 0;
 191 
 192   constantPoolCacheOop cache = NULL;
 193   if (in_cp_cache) {
 194     cache = constants->cache();
 195     if (cache != NULL) {
 196       //climit = cache->length();  // %%% private!
 197       size_t size = cache->size() * HeapWordSize;
 198       size -= sizeof(constantPoolCacheOopDesc);
 199       size /= sizeof(ConstantPoolCacheEntry);
 200       climit = (int) size;
 201     }
 202   }
 203 
 204   if (in_cp_cache && constantPoolCacheOopDesc::is_secondary_index(i)) {
 205     i = constantPoolCacheOopDesc::decode_secondary_index(i);
 206     st->print(" secondary cache[%d] of", i);
 207     if (i >= 0 && i < climit) {
 208       if (!cache->entry_at(i)->is_secondary_entry()) {
 209         st->print_cr(" not secondary entry?", i);
 210         return false;
 211       }
 212       i = cache->entry_at(i)->main_entry_index();
 213       goto check_cache_index;
 214     } else {
 215       st->print_cr(" not in cache[*]?", i);
 216       return false;
 217     }
 218   }
 219 
 220   if (cache != NULL) {
 221     i = Bytes::swap_u2(i);
 222     if (WizardMode)  st->print(" (swap=%d)", i);
 223     goto check_cache_index;
 224   }
 225 
 226  check_cp_index:
 227   if (i >= 0 && i < ilimit) {
 228     if (WizardMode)  st->print(" cp[%d]", i);
 229     cp_index = i;
 230     return true;
 231   }
 232 
 233   st->print_cr(" CP[%d] not in CP", i);
 234   return false;
 235 
 236  check_cache_index:
 237   if (i >= 0 && i < climit) {
 238     if (cache->entry_at(i)->is_secondary_entry()) {
 239       st->print_cr(" secondary entry?");
 240       return false;
 241     }
 242     i = cache->entry_at(i)->constant_pool_index();
 243     goto check_cp_index;
 244   }
 245   st->print_cr(" not in CP[*]?", i);
 246   return false;
 247 }
 248 
 249 void BytecodePrinter::print_constant(int i, outputStream* st) {
 250   int orig_i = i;
 251   if (!check_index(orig_i, false, i, st))  return;
 252 
 253   constantPoolOop constants = method()->constants();
 254   constantTag tag = constants->tag_at(i);
 255 
 256   if (tag.is_int()) {
 257     st->print_cr(" " INT32_FORMAT, constants->int_at(i));
 258   } else if (tag.is_long()) {
 259     st->print_cr(" " INT64_FORMAT, constants->long_at(i));
 260   } else if (tag.is_float()) {
 261     st->print_cr(" %f", constants->float_at(i));
 262   } else if (tag.is_double()) {
 263     st->print_cr(" %f", constants->double_at(i));
 264   } else if (tag.is_string()) {
 265     oop string = constants->resolved_string_at(i);
 266     print_oop(string, st);
 267   } else if (tag.is_unresolved_string()) {
 268     st->print_cr(" <unresolved string at %d>", i);
 269   } else if (tag.is_klass()) {
 270     st->print_cr(" %s", constants->resolved_klass_at(i)->klass_part()->external_name());
 271   } else if (tag.is_unresolved_klass()) {
 272     st->print_cr(" <unresolved klass at %d>", i);
 273   } else if (tag.is_object()) {
 274     st->print_cr(" " PTR_FORMAT, constants->object_at(i));
 275   } else {
 276     st->print_cr(" bad tag=%d at %d", tag.value(), i);
 277   }
 278 }
 279 
 280 void BytecodePrinter::print_field_or_method(int i, outputStream* st) {
 281   int orig_i = i;
 282   if (!check_index(orig_i, true, i, st))  return;
 283 
 284   constantPoolOop constants = method()->constants();
 285   constantTag tag = constants->tag_at(i);
 286 
 287   int nt_index = -1;
 288 
 289   switch (tag.value()) {
 290   case JVM_CONSTANT_InterfaceMethodref:
 291   case JVM_CONSTANT_Methodref:
 292   case JVM_CONSTANT_Fieldref:
 293   case JVM_CONSTANT_NameAndType:
 294     break;
 295   default:
 296     st->print_cr(" bad tag=%d at %d", tag.value(), i);
 297     return;
 298   }
 299 
 300   symbolOop name = constants->uncached_name_ref_at(i);
 301   symbolOop signature = constants->uncached_signature_ref_at(i);
 302   st->print_cr(" %d <%s> <%s> ", i, name->as_C_string(), signature->as_C_string());
 303 }
 304 
 305 
 306 void BytecodePrinter::print_attributes(Bytecodes::Code code, int bci, outputStream* st) {
 307   // Show attributes of pre-rewritten codes
 308   code = Bytecodes::java_code(code);
 309   // If the code doesn't have any fields there's nothing to print.
 310   // note this is ==1 because the tableswitch and lookupswitch are
 311   // zero size (for some reason) and we want to print stuff out for them.
 312   if (Bytecodes::length_for(code) == 1) {
 313     st->cr();
 314     return;
 315   }
 316 
 317   switch(code) {
 318     // Java specific bytecodes only matter.
 319     case Bytecodes::_bipush:
 320       st->print_cr(" " INT32_FORMAT, get_byte());
 321       break;
 322     case Bytecodes::_sipush:
 323       st->print_cr(" " INT32_FORMAT, get_short());
 324       break;
 325     case Bytecodes::_ldc:
 326       print_constant(get_index(), st);
 327       break;
 328 
 329     case Bytecodes::_ldc_w:
 330     case Bytecodes::_ldc2_w:
 331       print_constant(get_big_index(), st);
 332       break;
 333 
 334     case Bytecodes::_iload:
 335     case Bytecodes::_lload:
 336     case Bytecodes::_fload:
 337     case Bytecodes::_dload:
 338     case Bytecodes::_aload:
 339     case Bytecodes::_istore:
 340     case Bytecodes::_lstore:
 341     case Bytecodes::_fstore:
 342     case Bytecodes::_dstore:
 343     case Bytecodes::_astore:
 344       st->print_cr(" #%d", get_index_special());
 345       break;
 346 
 347     case Bytecodes::_iinc:
 348       { int index = get_index_special();
 349         jint offset = is_wide() ? get_short(): get_byte();
 350         st->print_cr(" #%d " INT32_FORMAT, index, offset);
 351       }
 352       break;
 353 
 354     case Bytecodes::_newarray: {
 355         BasicType atype = (BasicType)get_index();
 356         const char* str = type2name(atype);
 357         if (str == NULL || atype == T_OBJECT || atype == T_ARRAY) {
 358           assert(false, "Unidentified basic type");
 359         }
 360         st->print_cr(" %s", str);
 361       }
 362       break;
 363     case Bytecodes::_anewarray: {
 364         int klass_index = get_big_index();
 365         constantPoolOop constants = method()->constants();
 366         symbolOop name = constants->klass_name_at(klass_index);
 367         st->print_cr(" %s ", name->as_C_string());
 368       }
 369       break;
 370     case Bytecodes::_multianewarray: {
 371         int klass_index = get_big_index();
 372         int nof_dims = get_index();
 373         constantPoolOop constants = method()->constants();
 374         symbolOop name = constants->klass_name_at(klass_index);
 375         st->print_cr(" %s %d", name->as_C_string(), nof_dims);
 376       }
 377       break;
 378 
 379     case Bytecodes::_ifeq:
 380     case Bytecodes::_ifnull:
 381     case Bytecodes::_iflt:
 382     case Bytecodes::_ifle:
 383     case Bytecodes::_ifne:
 384     case Bytecodes::_ifnonnull:
 385     case Bytecodes::_ifgt:
 386     case Bytecodes::_ifge:
 387     case Bytecodes::_if_icmpeq:
 388     case Bytecodes::_if_icmpne:
 389     case Bytecodes::_if_icmplt:
 390     case Bytecodes::_if_icmpgt:
 391     case Bytecodes::_if_icmple:
 392     case Bytecodes::_if_icmpge:
 393     case Bytecodes::_if_acmpeq:
 394     case Bytecodes::_if_acmpne:
 395     case Bytecodes::_goto:
 396     case Bytecodes::_jsr:
 397       st->print_cr(" %d", bci + get_short());
 398       break;
 399 
 400     case Bytecodes::_goto_w:
 401     case Bytecodes::_jsr_w:
 402       st->print_cr(" %d", bci + get_int());
 403       break;
 404 
 405     case Bytecodes::_ret: st->print_cr(" %d", get_index_special()); break;
 406 
 407     case Bytecodes::_tableswitch:
 408       { align();
 409         int  default_dest = bci + get_int();
 410         int  lo           = get_int();
 411         int  hi           = get_int();
 412         int  len          = hi - lo + 1;
 413         jint* dest        = NEW_RESOURCE_ARRAY(jint, len);
 414         for (int i = 0; i < len; i++) {
 415           dest[i] = bci + get_int();
 416         }
 417         st->print(" %d " INT32_FORMAT " " INT32_FORMAT " ",
 418                       default_dest, lo, hi);
 419         int first = true;
 420         for (int ll = lo; ll <= hi; ll++, first = false)  {
 421           int idx = ll - lo;
 422           const char *format = first ? " %d:" INT32_FORMAT " (delta: %d)" :
 423                                        ", %d:" INT32_FORMAT " (delta: %d)";
 424           st->print(format, ll, dest[idx], dest[idx]-bci);
 425         }
 426         st->cr();
 427       }
 428       break;
 429     case Bytecodes::_lookupswitch:
 430       { align();
 431         int  default_dest = bci + get_int();
 432         int  len          = get_int();
 433         jint* key         = NEW_RESOURCE_ARRAY(jint, len);
 434         jint* dest        = NEW_RESOURCE_ARRAY(jint, len);
 435         for (int i = 0; i < len; i++) {
 436           key [i] = get_int();
 437           dest[i] = bci + get_int();
 438         };
 439         st->print(" %d %d ", default_dest, len);
 440         bool first = true;
 441         for (int ll = 0; ll < len; ll++, first = false)  {
 442           const char *format = first ? " " INT32_FORMAT ":" INT32_FORMAT :
 443                                        ", " INT32_FORMAT ":" INT32_FORMAT ;
 444           st->print(format, key[ll], dest[ll]);
 445         }
 446         st->cr();
 447       }
 448       break;
 449 
 450     case Bytecodes::_putstatic:
 451     case Bytecodes::_getstatic:
 452     case Bytecodes::_putfield:
 453     case Bytecodes::_getfield:
 454       print_field_or_method(get_big_index(), st);
 455       break;
 456 
 457     case Bytecodes::_invokevirtual:
 458     case Bytecodes::_invokespecial:
 459     case Bytecodes::_invokestatic:
 460       print_field_or_method(get_big_index(), st);
 461       break;
 462 
 463     case Bytecodes::_invokeinterface:
 464       { int i = get_big_index();
 465         int n = get_index();
 466         get_index();            // ignore zero byte
 467         print_field_or_method(i, st);
 468       }
 469       break;
 470 
 471     case Bytecodes::_invokedynamic:
 472       print_field_or_method(get_giant_index(), st);
 473       break;
 474 
 475     case Bytecodes::_new:
 476     case Bytecodes::_checkcast:
 477     case Bytecodes::_instanceof:
 478       { int i = get_big_index();
 479         constantPoolOop constants = method()->constants();
 480         symbolOop name = constants->klass_name_at(i);
 481         st->print_cr(" %d <%s>", i, name->as_C_string());
 482       }
 483       break;
 484 
 485     case Bytecodes::_wide:
 486       // length is zero not one, but printed with no more info.
 487       break;
 488 
 489     default:
 490       ShouldNotReachHere();
 491       break;
 492   }
 493 }
 494 
 495 
 496 void BytecodePrinter::bytecode_epilog(int bci, outputStream* st) {
 497   methodDataOop mdo = method()->method_data();
 498   if (mdo != NULL) {
 499     ProfileData* data = mdo->bci_to_data(bci);
 500     if (data != NULL) {
 501       st->print("  %d", mdo->dp_to_di(data->dp()));
 502       st->fill_to(6);
 503       data->print_data_on(st);
 504     }
 505   }
 506 }
 507 #endif // PRODUCT