bytecodeTracer.cpp revision 726:be93aad57795 
1/*
2 * Copyright 1997-2007 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
34class 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
141BytecodeClosure* BytecodeTracer::_closure = NULL;
142
143static BytecodePrinter std_closure;
144BytecodeClosure* BytecodeTracer::std_closure() {
145  return &::std_closure;
146}
147
148
149void 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
168void 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
173void 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
188bool 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
249void 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 {
274    st->print_cr(" bad tag=%d at %d", tag.value(), i);
275  }
276}
277
278void BytecodePrinter::print_field_or_method(int i, outputStream* st) {
279  int orig_i = i;
280  if (!check_index(orig_i, true, i, st))  return;
281
282  constantPoolOop constants = method()->constants();
283  constantTag tag = constants->tag_at(i);
284
285  switch (tag.value()) {
286  case JVM_CONSTANT_InterfaceMethodref:
287  case JVM_CONSTANT_Methodref:
288  case JVM_CONSTANT_Fieldref:
289    break;
290  default:
291    st->print_cr(" bad tag=%d at %d", tag.value(), i);
292    return;
293  }
294
295  symbolOop name = constants->name_ref_at(orig_i);
296  symbolOop signature = constants->signature_ref_at(orig_i);
297  st->print_cr(" %d <%s> <%s> ", i, name->as_C_string(), signature->as_C_string());
298}
299
300
301void BytecodePrinter::print_attributes(Bytecodes::Code code, int bci, outputStream* st) {
302  // Show attributes of pre-rewritten codes
303  // If the code doesn't have any fields there's nothing to print.
304  // note this is ==1 because the tableswitch and lookupswitch are
305  // zero size (for some reason) and we want to print stuff out for them.
306  if (Bytecodes::length_for(code) == 1) {
307    st->cr();
308    return;
309  }
310
311  switch(code) {
312    // Java specific bytecodes only matter.
313    case Bytecodes::_bipush:
314      st->print_cr(" " INT32_FORMAT, get_byte());
315      break;
316    case Bytecodes::_sipush:
317      st->print_cr(" " INT32_FORMAT, get_short());
318      break;
319    case Bytecodes::_ldc:
320      print_constant(get_index(), st);
321      break;
322
323    case Bytecodes::_ldc_w:
324    case Bytecodes::_ldc2_w:
325      print_constant(get_big_index(), st);
326      break;
327
328    case Bytecodes::_iload:
329    case Bytecodes::_lload:
330    case Bytecodes::_fload:
331    case Bytecodes::_dload:
332    case Bytecodes::_aload:
333    case Bytecodes::_istore:
334    case Bytecodes::_lstore:
335    case Bytecodes::_fstore:
336    case Bytecodes::_dstore:
337    case Bytecodes::_astore:
338      st->print_cr(" #%d", get_index_special());
339      break;
340
341    case Bytecodes::_iinc:
342      { int index = get_index_special();
343        jint offset = is_wide() ? get_short(): get_byte();
344        st->print_cr(" #%d " INT32_FORMAT, index, offset);
345      }
346      break;
347
348    case Bytecodes::_newarray: {
349        BasicType atype = (BasicType)get_index();
350        const char* str = type2name(atype);
351        if (str == NULL || atype == T_OBJECT || atype == T_ARRAY) {
352          assert(false, "Unidentified basic type");
353        }
354        st->print_cr(" %s", str);
355      }
356      break;
357    case Bytecodes::_anewarray: {
358        int klass_index = get_big_index();
359        constantPoolOop constants = method()->constants();
360        symbolOop name = constants->klass_name_at(klass_index);
361        st->print_cr(" %s ", name->as_C_string());
362      }
363      break;
364    case Bytecodes::_multianewarray: {
365        int klass_index = get_big_index();
366        int nof_dims = get_index();
367        constantPoolOop constants = method()->constants();
368        symbolOop name = constants->klass_name_at(klass_index);
369        st->print_cr(" %s %d", name->as_C_string(), nof_dims);
370      }
371      break;
372
373    case Bytecodes::_ifeq:
374    case Bytecodes::_ifnull:
375    case Bytecodes::_iflt:
376    case Bytecodes::_ifle:
377    case Bytecodes::_ifne:
378    case Bytecodes::_ifnonnull:
379    case Bytecodes::_ifgt:
380    case Bytecodes::_ifge:
381    case Bytecodes::_if_icmpeq:
382    case Bytecodes::_if_icmpne:
383    case Bytecodes::_if_icmplt:
384    case Bytecodes::_if_icmpgt:
385    case Bytecodes::_if_icmple:
386    case Bytecodes::_if_icmpge:
387    case Bytecodes::_if_acmpeq:
388    case Bytecodes::_if_acmpne:
389    case Bytecodes::_goto:
390    case Bytecodes::_jsr:
391      st->print_cr(" %d", bci + get_short());
392      break;
393
394    case Bytecodes::_goto_w:
395    case Bytecodes::_jsr_w:
396      st->print_cr(" %d", bci + get_int());
397      break;
398
399    case Bytecodes::_ret: st->print_cr(" %d", get_index_special()); break;
400
401    case Bytecodes::_tableswitch:
402      { align();
403        int  default_dest = bci + get_int();
404        int  lo           = get_int();
405        int  hi           = get_int();
406        int  len          = hi - lo + 1;
407        jint* dest        = NEW_RESOURCE_ARRAY(jint, len);
408        for (int i = 0; i < len; i++) {
409          dest[i] = bci + get_int();
410        }
411        st->print(" %d " INT32_FORMAT " " INT32_FORMAT " ",
412                      default_dest, lo, hi);
413        int first = true;
414        for (int ll = lo; ll <= hi; ll++, first = false)  {
415          int idx = ll - lo;
416          const char *format = first ? " %d:" INT32_FORMAT " (delta: %d)" :
417                                       ", %d:" INT32_FORMAT " (delta: %d)";
418          st->print(format, ll, dest[idx], dest[idx]-bci);
419        }
420        st->cr();
421      }
422      break;
423    case Bytecodes::_lookupswitch:
424      { align();
425        int  default_dest = bci + get_int();
426        int  len          = get_int();
427        jint* key         = NEW_RESOURCE_ARRAY(jint, len);
428        jint* dest        = NEW_RESOURCE_ARRAY(jint, len);
429        for (int i = 0; i < len; i++) {
430          key [i] = get_int();
431          dest[i] = bci + get_int();
432        };
433        st->print(" %d %d ", default_dest, len);
434        bool first = true;
435        for (int ll = 0; ll < len; ll++, first = false)  {
436          const char *format = first ? " " INT32_FORMAT ":" INT32_FORMAT :
437                                       ", " INT32_FORMAT ":" INT32_FORMAT ;
438          st->print(format, key[ll], dest[ll]);
439        }
440        st->cr();
441      }
442      break;
443
444    case Bytecodes::_putstatic:
445    case Bytecodes::_getstatic:
446    case Bytecodes::_putfield:
447    case Bytecodes::_getfield:
448      print_field_or_method(get_big_index(), st);
449      break;
450
451    case Bytecodes::_invokevirtual:
452    case Bytecodes::_invokespecial:
453    case Bytecodes::_invokestatic:
454      print_field_or_method(get_big_index(), st);
455      break;
456
457    case Bytecodes::_invokeinterface:
458      { int i = get_big_index();
459        int n = get_index();
460        get_index();            // ignore zero byte
461        print_field_or_method(i, st);
462      }
463      break;
464
465    case Bytecodes::_invokedynamic:
466      print_field_or_method(get_giant_index(), st);
467      break;
468
469    case Bytecodes::_new:
470    case Bytecodes::_checkcast:
471    case Bytecodes::_instanceof:
472      { int i = get_big_index();
473        constantPoolOop constants = method()->constants();
474        symbolOop name = constants->klass_name_at(i);
475        st->print_cr(" %d <%s>", i, name->as_C_string());
476      }
477      break;
478
479    case Bytecodes::_wide:
480      // length is zero not one, but printed with no more info.
481      break;
482
483    default:
484      ShouldNotReachHere();
485      break;
486  }
487}
488
489
490void BytecodePrinter::bytecode_epilog(int bci, outputStream* st) {
491  methodDataOop mdo = method()->method_data();
492  if (mdo != NULL) {
493    ProfileData* data = mdo->bci_to_data(bci);
494    if (data != NULL) {
495      st->print("  %d", mdo->dp_to_di(data->dp()));
496      st->fill_to(6);
497      data->print_data_on(st);
498    }
499  }
500}
501#endif // PRODUCT
502