1 /*
   2  * Copyright (c) 1997, 2016, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/metadataOnStackMark.hpp"
  27 #include "classfile/systemDictionary.hpp"
  28 #include "code/codeCache.hpp"
  29 #include "code/debugInfoRec.hpp"
  30 #include "gc/shared/collectedHeap.inline.hpp"
  31 #include "gc/shared/gcLocker.hpp"
  32 #include "gc/shared/generation.hpp"
  33 #include "interpreter/bytecodeStream.hpp"
  34 #include "interpreter/bytecodeTracer.hpp"
  35 #include "interpreter/bytecodes.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "interpreter/oopMapCache.hpp"
  38 #include "memory/heapInspection.hpp"
  39 #include "memory/metadataFactory.hpp"
  40 #include "memory/metaspaceShared.hpp"
  41 #include "memory/oopFactory.hpp"
  42 #include "memory/resourceArea.hpp"
  43 #include "oops/constMethod.hpp"
  44 #include "oops/method.hpp"
  45 #include "oops/methodData.hpp"
  46 #include "oops/objArrayOop.inline.hpp"
  47 #include "oops/oop.inline.hpp"
  48 #include "oops/symbol.hpp"
  49 #include "prims/jvmtiExport.hpp"
  50 #include "prims/methodHandles.hpp"
  51 #include "prims/nativeLookup.hpp"
  52 #include "runtime/arguments.hpp"
  53 #include "runtime/compilationPolicy.hpp"
  54 #include "runtime/frame.inline.hpp"
  55 #include "runtime/handles.inline.hpp"
  56 #include "runtime/orderAccess.inline.hpp"
  57 #include "runtime/relocator.hpp"
  58 #include "runtime/sharedRuntime.hpp"
  59 #include "runtime/signature.hpp"
  60 #include "utilities/quickSort.hpp"
  61 #include "utilities/xmlstream.hpp"
  62 
  63 // Implementation of Method
  64 
  65 Method* Method::allocate(ClassLoaderData* loader_data,
  66                          int byte_code_size,
  67                          AccessFlags access_flags,
  68                          InlineTableSizes* sizes,
  69                          ConstMethod::MethodType method_type,
  70                          TRAPS) {
  71   assert(!access_flags.is_native() || byte_code_size == 0,
  72          "native methods should not contain byte codes");
  73   ConstMethod* cm = ConstMethod::allocate(loader_data,
  74                                           byte_code_size,
  75                                           sizes,
  76                                           method_type,
  77                                           CHECK_NULL);
  78   int size = Method::size(access_flags.is_native());
  79   return new (loader_data, size, false, MetaspaceObj::MethodType, THREAD) Method(cm, access_flags);
  80 }
  81 
  82 Method::Method(ConstMethod* xconst, AccessFlags access_flags) {
  83   NoSafepointVerifier no_safepoint;
  84   set_constMethod(xconst);
  85   set_access_flags(access_flags);
  86   set_intrinsic_id(vmIntrinsics::_none);
  87   set_jfr_towrite(false);
  88   set_force_inline(false);
  89   set_hidden(false);
  90   set_dont_inline(false);
  91   set_has_injected_profile(false);
  92   set_method_data(NULL);
  93   clear_method_counters();
  94   set_vtable_index(Method::garbage_vtable_index);
  95 
  96   // Fix and bury in Method*
  97   set_interpreter_entry(NULL); // sets i2i entry and from_int
  98   set_adapter_entry(NULL);
  99   clear_code(); // from_c/from_i get set to c2i/i2i
 100 
 101   if (access_flags.is_native()) {
 102     clear_native_function();
 103     set_signature_handler(NULL);
 104   }
 105 
 106   NOT_PRODUCT(set_compiled_invocation_count(0);)
 107 }
 108 
 109 // Release Method*.  The nmethod will be gone when we get here because
 110 // we've walked the code cache.
 111 void Method::deallocate_contents(ClassLoaderData* loader_data) {
 112   MetadataFactory::free_metadata(loader_data, constMethod());
 113   set_constMethod(NULL);
 114   MetadataFactory::free_metadata(loader_data, method_data());
 115   set_method_data(NULL);
 116   MetadataFactory::free_metadata(loader_data, method_counters());
 117   clear_method_counters();
 118   // The nmethod will be gone when we get here.
 119   if (code() != NULL) _code = NULL;
 120 }
 121 
 122 address Method::get_i2c_entry() {
 123   assert(adapter() != NULL, "must have");
 124   return adapter()->get_i2c_entry();
 125 }
 126 
 127 address Method::get_c2i_entry() {
 128   assert(adapter() != NULL, "must have");
 129   return adapter()->get_c2i_entry();
 130 }
 131 
 132 address Method::get_c2i_unverified_entry() {
 133   assert(adapter() != NULL, "must have");
 134   return adapter()->get_c2i_unverified_entry();
 135 }
 136 
 137 char* Method::name_and_sig_as_C_string() const {
 138   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature());
 139 }
 140 
 141 char* Method::name_and_sig_as_C_string(char* buf, int size) const {
 142   return name_and_sig_as_C_string(constants()->pool_holder(), name(), signature(), buf, size);
 143 }
 144 
 145 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature) {
 146   const char* klass_name = klass->external_name();
 147   int klass_name_len  = (int)strlen(klass_name);
 148   int method_name_len = method_name->utf8_length();
 149   int len             = klass_name_len + 1 + method_name_len + signature->utf8_length();
 150   char* dest          = NEW_RESOURCE_ARRAY(char, len + 1);
 151   strcpy(dest, klass_name);
 152   dest[klass_name_len] = '.';
 153   strcpy(&dest[klass_name_len + 1], method_name->as_C_string());
 154   strcpy(&dest[klass_name_len + 1 + method_name_len], signature->as_C_string());
 155   dest[len] = 0;
 156   return dest;
 157 }
 158 
 159 char* Method::name_and_sig_as_C_string(Klass* klass, Symbol* method_name, Symbol* signature, char* buf, int size) {
 160   Symbol* klass_name = klass->name();
 161   klass_name->as_klass_external_name(buf, size);
 162   int len = (int)strlen(buf);
 163 
 164   if (len < size - 1) {
 165     buf[len++] = '.';
 166 
 167     method_name->as_C_string(&(buf[len]), size - len);
 168     len = (int)strlen(buf);
 169 
 170     signature->as_C_string(&(buf[len]), size - len);
 171   }
 172 
 173   return buf;
 174 }
 175 
 176 int Method::fast_exception_handler_bci_for(methodHandle mh, KlassHandle ex_klass, int throw_bci, TRAPS) {
 177   // exception table holds quadruple entries of the form (beg_bci, end_bci, handler_bci, klass_index)
 178   // access exception table
 179   ExceptionTable table(mh());
 180   int length = table.length();
 181   // iterate through all entries sequentially
 182   constantPoolHandle pool(THREAD, mh->constants());
 183   for (int i = 0; i < length; i ++) {
 184     //reacquire the table in case a GC happened
 185     ExceptionTable table(mh());
 186     int beg_bci = table.start_pc(i);
 187     int end_bci = table.end_pc(i);
 188     assert(beg_bci <= end_bci, "inconsistent exception table");
 189     if (beg_bci <= throw_bci && throw_bci < end_bci) {
 190       // exception handler bci range covers throw_bci => investigate further
 191       int handler_bci = table.handler_pc(i);
 192       int klass_index = table.catch_type_index(i);
 193       if (klass_index == 0) {
 194         return handler_bci;
 195       } else if (ex_klass.is_null()) {
 196         return handler_bci;
 197       } else {
 198         // we know the exception class => get the constraint class
 199         // this may require loading of the constraint class; if verification
 200         // fails or some other exception occurs, return handler_bci
 201         Klass* k = pool->klass_at(klass_index, CHECK_(handler_bci));
 202         KlassHandle klass = KlassHandle(THREAD, k);
 203         assert(klass.not_null(), "klass not loaded");
 204         if (ex_klass->is_subtype_of(klass())) {
 205           return handler_bci;
 206         }
 207       }
 208     }
 209   }
 210 
 211   return -1;
 212 }
 213 
 214 void Method::mask_for(int bci, InterpreterOopMap* mask) {
 215 
 216   Thread* myThread    = Thread::current();
 217   methodHandle h_this(myThread, this);
 218 #if defined(ASSERT) && !INCLUDE_JVMCI
 219   bool has_capability = myThread->is_VM_thread() ||
 220                         myThread->is_ConcurrentGC_thread() ||
 221                         myThread->is_GC_task_thread();
 222 
 223   if (!has_capability) {
 224     if (!VerifyStack && !VerifyLastFrame) {
 225       // verify stack calls this outside VM thread
 226       warning("oopmap should only be accessed by the "
 227               "VM, GC task or CMS threads (or during debugging)");
 228       InterpreterOopMap local_mask;
 229       method_holder()->mask_for(h_this, bci, &local_mask);
 230       local_mask.print();
 231     }
 232   }
 233 #endif
 234   method_holder()->mask_for(h_this, bci, mask);
 235   return;
 236 }
 237 
 238 
 239 int Method::bci_from(address bcp) const {
 240   if (is_native() && bcp == 0) {
 241     return 0;
 242   }
 243 #ifdef ASSERT
 244   {
 245     ResourceMark rm;
 246     assert(is_native() && bcp == code_base() || contains(bcp) || is_error_reported(),
 247            "bcp doesn't belong to this method: bcp: " INTPTR_FORMAT ", method: %s",
 248            p2i(bcp), name_and_sig_as_C_string());
 249   }
 250 #endif
 251   return bcp - code_base();
 252 }
 253 
 254 
 255 int Method::validate_bci(int bci) const {
 256   return (bci == 0 || bci < code_size()) ? bci : -1;
 257 }
 258 
 259 // Return bci if it appears to be a valid bcp
 260 // Return -1 otherwise.
 261 // Used by profiling code, when invalid data is a possibility.
 262 // The caller is responsible for validating the Method* itself.
 263 int Method::validate_bci_from_bcp(address bcp) const {
 264   // keep bci as -1 if not a valid bci
 265   int bci = -1;
 266   if (bcp == 0 || bcp == code_base()) {
 267     // code_size() may return 0 and we allow 0 here
 268     // the method may be native
 269     bci = 0;
 270   } else if (contains(bcp)) {
 271     bci = bcp - code_base();
 272   }
 273   // Assert that if we have dodged any asserts, bci is negative.
 274   assert(bci == -1 || bci == bci_from(bcp_from(bci)), "sane bci if >=0");
 275   return bci;
 276 }
 277 
 278 address Method::bcp_from(int bci) const {
 279   assert((is_native() && bci == 0) || (!is_native() && 0 <= bci && bci < code_size()), "illegal bci: %d", bci);
 280   address bcp = code_base() + bci;
 281   assert(is_native() && bcp == code_base() || contains(bcp), "bcp doesn't belong to this method");
 282   return bcp;
 283 }
 284 
 285 address Method::bcp_from(address bcp) const {
 286   if (is_native() && bcp == NULL) {
 287     return code_base();
 288   } else {
 289     return bcp;
 290   }
 291 }
 292 
 293 int Method::size(bool is_native) {
 294   // If native, then include pointers for native_function and signature_handler
 295   int extra_bytes = (is_native) ? 2*sizeof(address*) : 0;
 296   int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
 297   return align_metadata_size(header_size() + extra_words);
 298 }
 299 
 300 
 301 Symbol* Method::klass_name() const {
 302   return method_holder()->name();
 303 }
 304 
 305 
 306 // Attempt to return method oop to original state.  Clear any pointers
 307 // (to objects outside the shared spaces).  We won't be able to predict
 308 // where they should point in a new JVM.  Further initialize some
 309 // entries now in order allow them to be write protected later.
 310 
 311 void Method::remove_unshareable_info() {
 312   unlink_method();
 313 }
 314 
 315 void Method::set_vtable_index(int index) {
 316   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 317     // At runtime initialize_vtable is rerun as part of link_class_impl()
 318     // for a shared class loaded by the non-boot loader to obtain the loader
 319     // constraints based on the runtime classloaders' context.
 320     return; // don't write into the shared class
 321   } else {
 322     _vtable_index = index;
 323   }
 324 }
 325 
 326 void Method::set_itable_index(int index) {
 327   if (is_shared() && !MetaspaceShared::remapped_readwrite()) {
 328     // At runtime initialize_itable is rerun as part of link_class_impl()
 329     // for a shared class loaded by the non-boot loader to obtain the loader
 330     // constraints based on the runtime classloaders' context. The dumptime
 331     // itable index should be the same as the runtime index.
 332     assert(_vtable_index == itable_index_max - index,
 333            "archived itable index is different from runtime index");
 334     return; // don’t write into the shared class
 335   } else {
 336     _vtable_index = itable_index_max - index;
 337   }
 338   assert(valid_itable_index(), "");
 339 }
 340 
 341 
 342 
 343 bool Method::was_executed_more_than(int n) {
 344   // Invocation counter is reset when the Method* is compiled.
 345   // If the method has compiled code we therefore assume it has
 346   // be excuted more than n times.
 347   if (is_accessor() || is_empty_method() || (code() != NULL)) {
 348     // interpreter doesn't bump invocation counter of trivial methods
 349     // compiler does not bump invocation counter of compiled methods
 350     return true;
 351   }
 352   else if ((method_counters() != NULL &&
 353             method_counters()->invocation_counter()->carry()) ||
 354            (method_data() != NULL &&
 355             method_data()->invocation_counter()->carry())) {
 356     // The carry bit is set when the counter overflows and causes
 357     // a compilation to occur.  We don't know how many times
 358     // the counter has been reset, so we simply assume it has
 359     // been executed more than n times.
 360     return true;
 361   } else {
 362     return invocation_count() > n;
 363   }
 364 }
 365 
 366 void Method::print_invocation_count() {
 367   if (is_static()) tty->print("static ");
 368   if (is_final()) tty->print("final ");
 369   if (is_synchronized()) tty->print("synchronized ");
 370   if (is_native()) tty->print("native ");
 371   tty->print("%s::", method_holder()->external_name());
 372   name()->print_symbol_on(tty);
 373   signature()->print_symbol_on(tty);
 374 
 375   if (WizardMode) {
 376     // dump the size of the byte codes
 377     tty->print(" {%d}", code_size());
 378   }
 379   tty->cr();
 380 
 381   tty->print_cr ("  interpreter_invocation_count: %8d ", interpreter_invocation_count());
 382   tty->print_cr ("  invocation_counter:           %8d ", invocation_count());
 383   tty->print_cr ("  backedge_counter:             %8d ", backedge_count());
 384 #ifndef PRODUCT
 385   if (CountCompiledCalls) {
 386     tty->print_cr ("  compiled_invocation_count: %8d ", compiled_invocation_count());
 387   }
 388 #endif
 389 }
 390 
 391 // Build a MethodData* object to hold information about this method
 392 // collected in the interpreter.
 393 void Method::build_interpreter_method_data(const methodHandle& method, TRAPS) {
 394   // Do not profile the method if metaspace has hit an OOM previously
 395   // allocating profiling data. Callers clear pending exception so don't
 396   // add one here.
 397   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 398     return;
 399   }
 400 
 401   // Grab a lock here to prevent multiple
 402   // MethodData*s from being created.
 403   MutexLocker ml(MethodData_lock, THREAD);
 404   if (method->method_data() == NULL) {
 405     ClassLoaderData* loader_data = method->method_holder()->class_loader_data();
 406     MethodData* method_data = MethodData::allocate(loader_data, method, THREAD);
 407     if (HAS_PENDING_EXCEPTION) {
 408       CompileBroker::log_metaspace_failure();
 409       ClassLoaderDataGraph::set_metaspace_oom(true);
 410       return;   // return the exception (which is cleared)
 411     }
 412 
 413     method->set_method_data(method_data);
 414     if (PrintMethodData && (Verbose || WizardMode)) {
 415       ResourceMark rm(THREAD);
 416       tty->print("build_interpreter_method_data for ");
 417       method->print_name(tty);
 418       tty->cr();
 419       // At the end of the run, the MDO, full of data, will be dumped.
 420     }
 421   }
 422 }
 423 
 424 MethodCounters* Method::build_method_counters(Method* m, TRAPS) {
 425   // Do not profile the method if metaspace has hit an OOM previously
 426   if (ClassLoaderDataGraph::has_metaspace_oom()) {
 427     return NULL;
 428   }
 429 
 430   methodHandle mh(m);
 431   MethodCounters* counters = MethodCounters::allocate(mh, THREAD);
 432   if (HAS_PENDING_EXCEPTION) {
 433     CompileBroker::log_metaspace_failure();
 434     ClassLoaderDataGraph::set_metaspace_oom(true);
 435     return NULL;   // return the exception (which is cleared)
 436   }
 437   if (!mh->init_method_counters(counters)) {
 438     MetadataFactory::free_metadata(mh->method_holder()->class_loader_data(), counters);
 439   }
 440 
 441   if (LogTouchedMethods) {
 442     mh->log_touched(CHECK_NULL);
 443   }
 444 
 445   return mh->method_counters();
 446 }
 447 
 448 void Method::cleanup_inline_caches() {
 449   // The current system doesn't use inline caches in the interpreter
 450   // => nothing to do (keep this method around for future use)
 451 }
 452 
 453 
 454 int Method::extra_stack_words() {
 455   // not an inline function, to avoid a header dependency on Interpreter
 456   return extra_stack_entries() * Interpreter::stackElementSize;
 457 }
 458 
 459 
 460 void Method::compute_size_of_parameters(Thread *thread) {
 461   ArgumentSizeComputer asc(signature());
 462   set_size_of_parameters(asc.size() + (is_static() ? 0 : 1));
 463 }
 464 
 465 BasicType Method::result_type() const {
 466   ResultTypeFinder rtf(signature());
 467   return rtf.type();
 468 }
 469 
 470 
 471 bool Method::is_empty_method() const {
 472   return  code_size() == 1
 473       && *code_base() == Bytecodes::_return;
 474 }
 475 
 476 
 477 bool Method::is_vanilla_constructor() const {
 478   // Returns true if this method is a vanilla constructor, i.e. an "<init>" "()V" method
 479   // which only calls the superclass vanilla constructor and possibly does stores of
 480   // zero constants to local fields:
 481   //
 482   //   aload_0
 483   //   invokespecial
 484   //   indexbyte1
 485   //   indexbyte2
 486   //
 487   // followed by an (optional) sequence of:
 488   //
 489   //   aload_0
 490   //   aconst_null / iconst_0 / fconst_0 / dconst_0
 491   //   putfield
 492   //   indexbyte1
 493   //   indexbyte2
 494   //
 495   // followed by:
 496   //
 497   //   return
 498 
 499   assert(name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructors");
 500   assert(signature() == vmSymbols::void_method_signature(), "Should only be called for default constructors");
 501   int size = code_size();
 502   // Check if size match
 503   if (size == 0 || size % 5 != 0) return false;
 504   address cb = code_base();
 505   int last = size - 1;
 506   if (cb[0] != Bytecodes::_aload_0 || cb[1] != Bytecodes::_invokespecial || cb[last] != Bytecodes::_return) {
 507     // Does not call superclass default constructor
 508     return false;
 509   }
 510   // Check optional sequence
 511   for (int i = 4; i < last; i += 5) {
 512     if (cb[i] != Bytecodes::_aload_0) return false;
 513     if (!Bytecodes::is_zero_const(Bytecodes::cast(cb[i+1]))) return false;
 514     if (cb[i+2] != Bytecodes::_putfield) return false;
 515   }
 516   return true;
 517 }
 518 
 519 
 520 bool Method::compute_has_loops_flag() {
 521   BytecodeStream bcs(this);
 522   Bytecodes::Code bc;
 523 
 524   while ((bc = bcs.next()) >= 0) {
 525     switch( bc ) {
 526       case Bytecodes::_ifeq:
 527       case Bytecodes::_ifnull:
 528       case Bytecodes::_iflt:
 529       case Bytecodes::_ifle:
 530       case Bytecodes::_ifne:
 531       case Bytecodes::_ifnonnull:
 532       case Bytecodes::_ifgt:
 533       case Bytecodes::_ifge:
 534       case Bytecodes::_if_icmpeq:
 535       case Bytecodes::_if_icmpne:
 536       case Bytecodes::_if_icmplt:
 537       case Bytecodes::_if_icmpgt:
 538       case Bytecodes::_if_icmple:
 539       case Bytecodes::_if_icmpge:
 540       case Bytecodes::_if_acmpeq:
 541       case Bytecodes::_if_acmpne:
 542       case Bytecodes::_goto:
 543       case Bytecodes::_jsr:
 544         if( bcs.dest() < bcs.next_bci() ) _access_flags.set_has_loops();
 545         break;
 546 
 547       case Bytecodes::_goto_w:
 548       case Bytecodes::_jsr_w:
 549         if( bcs.dest_w() < bcs.next_bci() ) _access_flags.set_has_loops();
 550         break;
 551     }
 552   }
 553   _access_flags.set_loops_flag_init();
 554   return _access_flags.has_loops();
 555 }
 556 
 557 bool Method::is_final_method(AccessFlags class_access_flags) const {
 558   // or "does_not_require_vtable_entry"
 559   // default method or overpass can occur, is not final (reuses vtable entry)
 560   // private methods get vtable entries for backward class compatibility.
 561   if (is_overpass() || is_default_method())  return false;
 562   return is_final() || class_access_flags.is_final();
 563 }
 564 
 565 bool Method::is_final_method() const {
 566   return is_final_method(method_holder()->access_flags());
 567 }
 568 
 569 bool Method::is_default_method() const {
 570   if (method_holder() != NULL &&
 571       method_holder()->is_interface() &&
 572       !is_abstract()) {
 573     return true;
 574   } else {
 575     return false;
 576   }
 577 }
 578 
 579 bool Method::can_be_statically_bound(AccessFlags class_access_flags) const {
 580   if (is_final_method(class_access_flags))  return true;
 581 #ifdef ASSERT
 582   ResourceMark rm;
 583   bool is_nonv = (vtable_index() == nonvirtual_vtable_index);
 584   if (class_access_flags.is_interface()) {
 585     assert(is_nonv == is_static(), "is_nonv=%s", name_and_sig_as_C_string());
 586   }
 587 #endif
 588   assert(valid_vtable_index() || valid_itable_index(), "method must be linked before we ask this question");
 589   return vtable_index() == nonvirtual_vtable_index;
 590 }
 591 
 592 bool Method::can_be_statically_bound() const {
 593   return can_be_statically_bound(method_holder()->access_flags());
 594 }
 595 
 596 bool Method::is_accessor() const {
 597   return is_getter() || is_setter();
 598 }
 599 
 600 bool Method::is_getter() const {
 601   if (code_size() != 5) return false;
 602   if (size_of_parameters() != 1) return false;
 603   if (java_code_at(0) != Bytecodes::_aload_0)  return false;
 604   if (java_code_at(1) != Bytecodes::_getfield) return false;
 605   switch (java_code_at(4)) {
 606     case Bytecodes::_ireturn:
 607     case Bytecodes::_lreturn:
 608     case Bytecodes::_freturn:
 609     case Bytecodes::_dreturn:
 610     case Bytecodes::_areturn:
 611       break;
 612     default:
 613       return false;
 614   }
 615   return true;
 616 }
 617 
 618 bool Method::is_setter() const {
 619   if (code_size() != 6) return false;
 620   if (java_code_at(0) != Bytecodes::_aload_0) return false;
 621   switch (java_code_at(1)) {
 622     case Bytecodes::_iload_1:
 623     case Bytecodes::_aload_1:
 624     case Bytecodes::_fload_1:
 625       if (size_of_parameters() != 2) return false;
 626       break;
 627     case Bytecodes::_dload_1:
 628     case Bytecodes::_lload_1:
 629       if (size_of_parameters() != 3) return false;
 630       break;
 631     default:
 632       return false;
 633   }
 634   if (java_code_at(2) != Bytecodes::_putfield) return false;
 635   if (java_code_at(5) != Bytecodes::_return)   return false;
 636   return true;
 637 }
 638 
 639 bool Method::is_constant_getter() const {
 640   int last_index = code_size() - 1;
 641   // Check if the first 1-3 bytecodes are a constant push
 642   // and the last bytecode is a return.
 643   return (2 <= code_size() && code_size() <= 4 &&
 644           Bytecodes::is_const(java_code_at(0)) &&
 645           Bytecodes::length_for(java_code_at(0)) == last_index &&
 646           Bytecodes::is_return(java_code_at(last_index)));
 647 }
 648 
 649 bool Method::is_initializer() const {
 650   return is_object_initializer() || is_static_initializer();
 651 }
 652 
 653 bool Method::has_valid_initializer_flags() const {
 654   return (is_static() ||
 655           method_holder()->major_version() < 51);
 656 }
 657 
 658 bool Method::is_static_initializer() const {
 659   // For classfiles version 51 or greater, ensure that the clinit method is
 660   // static.  Non-static methods with the name "<clinit>" are not static
 661   // initializers. (older classfiles exempted for backward compatibility)
 662   return name() == vmSymbols::class_initializer_name() &&
 663          has_valid_initializer_flags();
 664 }
 665 
 666 bool Method::is_object_initializer() const {
 667    return name() == vmSymbols::object_initializer_name();
 668 }
 669 
 670 objArrayHandle Method::resolved_checked_exceptions_impl(Method* method, TRAPS) {
 671   int length = method->checked_exceptions_length();
 672   if (length == 0) {  // common case
 673     return objArrayHandle(THREAD, Universe::the_empty_class_klass_array());
 674   } else {
 675     methodHandle h_this(THREAD, method);
 676     objArrayOop m_oop = oopFactory::new_objArray(SystemDictionary::Class_klass(), length, CHECK_(objArrayHandle()));
 677     objArrayHandle mirrors (THREAD, m_oop);
 678     for (int i = 0; i < length; i++) {
 679       CheckedExceptionElement* table = h_this->checked_exceptions_start(); // recompute on each iteration, not gc safe
 680       Klass* k = h_this->constants()->klass_at(table[i].class_cp_index, CHECK_(objArrayHandle()));
 681       assert(k->is_subclass_of(SystemDictionary::Throwable_klass()), "invalid exception class");
 682       mirrors->obj_at_put(i, k->java_mirror());
 683     }
 684     return mirrors;
 685   }
 686 };
 687 
 688 
 689 int Method::line_number_from_bci(int bci) const {
 690   if (bci == SynchronizationEntryBCI) bci = 0;
 691   assert(bci == 0 || 0 <= bci && bci < code_size(), "illegal bci");
 692   int best_bci  =  0;
 693   int best_line = -1;
 694 
 695   if (has_linenumber_table()) {
 696     // The line numbers are a short array of 2-tuples [start_pc, line_number].
 697     // Not necessarily sorted and not necessarily one-to-one.
 698     CompressedLineNumberReadStream stream(compressed_linenumber_table());
 699     while (stream.read_pair()) {
 700       if (stream.bci() == bci) {
 701         // perfect match
 702         return stream.line();
 703       } else {
 704         // update best_bci/line
 705         if (stream.bci() < bci && stream.bci() >= best_bci) {
 706           best_bci  = stream.bci();
 707           best_line = stream.line();
 708         }
 709       }
 710     }
 711   }
 712   return best_line;
 713 }
 714 
 715 
 716 bool Method::is_klass_loaded_by_klass_index(int klass_index) const {
 717   if( constants()->tag_at(klass_index).is_unresolved_klass() ) {
 718     Thread *thread = Thread::current();
 719     Symbol* klass_name = constants()->klass_name_at(klass_index);
 720     Handle loader(thread, method_holder()->class_loader());
 721     Handle prot  (thread, method_holder()->protection_domain());
 722     return SystemDictionary::find(klass_name, loader, prot, thread) != NULL;
 723   } else {
 724     return true;
 725   }
 726 }
 727 
 728 
 729 bool Method::is_klass_loaded(int refinfo_index, bool must_be_resolved) const {
 730   int klass_index = constants()->klass_ref_index_at(refinfo_index);
 731   if (must_be_resolved) {
 732     // Make sure klass is resolved in constantpool.
 733     if (constants()->tag_at(klass_index).is_unresolved_klass()) return false;
 734   }
 735   return is_klass_loaded_by_klass_index(klass_index);
 736 }
 737 
 738 
 739 void Method::set_native_function(address function, bool post_event_flag) {
 740   assert(function != NULL, "use clear_native_function to unregister natives");
 741   assert(!is_method_handle_intrinsic() || function == SharedRuntime::native_method_throw_unsatisfied_link_error_entry(), "");
 742   address* native_function = native_function_addr();
 743 
 744   // We can see racers trying to place the same native function into place. Once
 745   // is plenty.
 746   address current = *native_function;
 747   if (current == function) return;
 748   if (post_event_flag && JvmtiExport::should_post_native_method_bind() &&
 749       function != NULL) {
 750     // native_method_throw_unsatisfied_link_error_entry() should only
 751     // be passed when post_event_flag is false.
 752     assert(function !=
 753       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 754       "post_event_flag mis-match");
 755 
 756     // post the bind event, and possible change the bind function
 757     JvmtiExport::post_native_method_bind(this, &function);
 758   }
 759   *native_function = function;
 760   // This function can be called more than once. We must make sure that we always
 761   // use the latest registered method -> check if a stub already has been generated.
 762   // If so, we have to make it not_entrant.
 763   CompiledMethod* nm = code(); // Put it into local variable to guard against concurrent updates
 764   if (nm != NULL) {
 765     nm->make_not_entrant();
 766   }
 767 }
 768 
 769 
 770 bool Method::has_native_function() const {
 771   if (is_method_handle_intrinsic())
 772     return false;  // special-cased in SharedRuntime::generate_native_wrapper
 773   address func = native_function();
 774   return (func != NULL && func != SharedRuntime::native_method_throw_unsatisfied_link_error_entry());
 775 }
 776 
 777 
 778 void Method::clear_native_function() {
 779   // Note: is_method_handle_intrinsic() is allowed here.
 780   set_native_function(
 781     SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 782     !native_bind_event_is_interesting);
 783   clear_code();
 784 }
 785 
 786 address Method::critical_native_function() {
 787   methodHandle mh(this);
 788   return NativeLookup::lookup_critical_entry(mh);
 789 }
 790 
 791 
 792 void Method::set_signature_handler(address handler) {
 793   address* signature_handler =  signature_handler_addr();
 794   *signature_handler = handler;
 795 }
 796 
 797 
 798 void Method::print_made_not_compilable(int comp_level, bool is_osr, bool report, const char* reason) {
 799   if (PrintCompilation && report) {
 800     ttyLocker ttyl;
 801     tty->print("made not %scompilable on ", is_osr ? "OSR " : "");
 802     if (comp_level == CompLevel_all) {
 803       tty->print("all levels ");
 804     } else {
 805       tty->print("levels ");
 806       for (int i = (int)CompLevel_none; i <= comp_level; i++) {
 807         tty->print("%d ", i);
 808       }
 809     }
 810     this->print_short_name(tty);
 811     int size = this->code_size();
 812     if (size > 0) {
 813       tty->print(" (%d bytes)", size);
 814     }
 815     if (reason != NULL) {
 816       tty->print("   %s", reason);
 817     }
 818     tty->cr();
 819   }
 820   if ((TraceDeoptimization || LogCompilation) && (xtty != NULL)) {
 821     ttyLocker ttyl;
 822     xtty->begin_elem("make_not_compilable thread='" UINTX_FORMAT "' osr='%d' level='%d'",
 823                      os::current_thread_id(), is_osr, comp_level);
 824     if (reason != NULL) {
 825       xtty->print(" reason=\'%s\'", reason);
 826     }
 827     xtty->method(this);
 828     xtty->stamp();
 829     xtty->end_elem();
 830   }
 831 }
 832 
 833 bool Method::is_always_compilable() const {
 834   // Generated adapters must be compiled
 835   if (is_method_handle_intrinsic() && is_synthetic()) {
 836     assert(!is_not_c1_compilable(), "sanity check");
 837     assert(!is_not_c2_compilable(), "sanity check");
 838     return true;
 839   }
 840 
 841   return false;
 842 }
 843 
 844 bool Method::is_not_compilable(int comp_level) const {
 845   if (number_of_breakpoints() > 0)
 846     return true;
 847   if (is_always_compilable())
 848     return false;
 849   if (comp_level == CompLevel_any)
 850     return is_not_c1_compilable() || is_not_c2_compilable();
 851   if (is_c1_compile(comp_level))
 852     return is_not_c1_compilable();
 853   if (is_c2_compile(comp_level))
 854     return is_not_c2_compilable();
 855   return false;
 856 }
 857 
 858 // call this when compiler finds that this method is not compilable
 859 void Method::set_not_compilable(int comp_level, bool report, const char* reason) {
 860   if (is_always_compilable()) {
 861     // Don't mark a method which should be always compilable
 862     return;
 863   }
 864   print_made_not_compilable(comp_level, /*is_osr*/ false, report, reason);
 865   if (comp_level == CompLevel_all) {
 866     set_not_c1_compilable();
 867     set_not_c2_compilable();
 868   } else {
 869     if (is_c1_compile(comp_level))
 870       set_not_c1_compilable();
 871     if (is_c2_compile(comp_level))
 872       set_not_c2_compilable();
 873   }
 874   CompilationPolicy::policy()->disable_compilation(this);
 875   assert(!CompilationPolicy::can_be_compiled(this, comp_level), "sanity check");
 876 }
 877 
 878 bool Method::is_not_osr_compilable(int comp_level) const {
 879   if (is_not_compilable(comp_level))
 880     return true;
 881   if (comp_level == CompLevel_any)
 882     return is_not_c1_osr_compilable() || is_not_c2_osr_compilable();
 883   if (is_c1_compile(comp_level))
 884     return is_not_c1_osr_compilable();
 885   if (is_c2_compile(comp_level))
 886     return is_not_c2_osr_compilable();
 887   return false;
 888 }
 889 
 890 void Method::set_not_osr_compilable(int comp_level, bool report, const char* reason) {
 891   print_made_not_compilable(comp_level, /*is_osr*/ true, report, reason);
 892   if (comp_level == CompLevel_all) {
 893     set_not_c1_osr_compilable();
 894     set_not_c2_osr_compilable();
 895   } else {
 896     if (is_c1_compile(comp_level))
 897       set_not_c1_osr_compilable();
 898     if (is_c2_compile(comp_level))
 899       set_not_c2_osr_compilable();
 900   }
 901   CompilationPolicy::policy()->disable_compilation(this);
 902   assert(!CompilationPolicy::can_be_osr_compiled(this, comp_level), "sanity check");
 903 }
 904 
 905 // Revert to using the interpreter and clear out the nmethod
 906 void Method::clear_code() {
 907 
 908   // this may be NULL if c2i adapters have not been made yet
 909   // Only should happen at allocate time.
 910   if (adapter() == NULL) {
 911     _from_compiled_entry    = NULL;
 912   } else {
 913     _from_compiled_entry    = adapter()->get_c2i_entry();
 914   }
 915   OrderAccess::storestore();
 916   _from_interpreted_entry = _i2i_entry;
 917   OrderAccess::storestore();
 918   _code = NULL;
 919 }
 920 
 921 #if INCLUDE_CDS
 922 // Called by class data sharing to remove any entry points (which are not shared)
 923 void Method::unlink_method() {
 924   _code = NULL;
 925 
 926   assert(DumpSharedSpaces, "dump time only");
 927   // Set the values to what they should be at run time. Note that
 928   // this Method can no longer be executed during dump time.
 929   _i2i_entry = Interpreter::entry_for_cds_method(this);
 930   _from_interpreted_entry = _i2i_entry;
 931 
 932   if (is_native()) {
 933     *native_function_addr() = NULL;
 934     set_signature_handler(NULL);
 935   }
 936   NOT_PRODUCT(set_compiled_invocation_count(0);)
 937 
 938   CDSAdapterHandlerEntry* cds_adapter = (CDSAdapterHandlerEntry*)adapter();
 939   constMethod()->set_adapter_trampoline(cds_adapter->get_adapter_trampoline());
 940   _from_compiled_entry = cds_adapter->get_c2i_entry_trampoline();
 941   assert(*((int*)_from_compiled_entry) == 0, "must be NULL during dump time, to be initialized at run time");
 942 
 943 
 944   // In case of DumpSharedSpaces, _method_data should always be NULL.
 945   assert(_method_data == NULL, "unexpected method data?");
 946 
 947   set_method_data(NULL);
 948   clear_method_counters();
 949 }
 950 #endif
 951 
 952 // Called when the method_holder is getting linked. Setup entrypoints so the method
 953 // is ready to be called from interpreter, compiler, and vtables.
 954 void Method::link_method(const methodHandle& h_method, TRAPS) {
 955   // If the code cache is full, we may reenter this function for the
 956   // leftover methods that weren't linked.
 957   if (is_shared()) {
 958     if (adapter() != NULL) return;
 959   } else {
 960     if (_i2i_entry != NULL) return;
 961 
 962     assert(adapter() == NULL, "init'd to NULL" );
 963   }
 964   assert( _code == NULL, "nothing compiled yet" );
 965 
 966   // Setup interpreter entrypoint
 967   assert(this == h_method(), "wrong h_method()" );
 968   address entry;
 969 
 970   if (this->is_shared()) {
 971     entry = Interpreter::entry_for_cds_method(h_method);
 972   } else {
 973     entry = Interpreter::entry_for_method(h_method);
 974   }
 975   assert(entry != NULL, "interpreter entry must be non-null");
 976   if (is_shared()) {
 977     assert(entry == _i2i_entry && entry == _from_interpreted_entry,
 978            "should be correctly set during dump time");
 979   } else {
 980     // Sets both _i2i_entry and _from_interpreted_entry
 981     set_interpreter_entry(entry);
 982   }
 983 
 984   // Don't overwrite already registered native entries.
 985   if (is_native() && !has_native_function()) {
 986     set_native_function(
 987       SharedRuntime::native_method_throw_unsatisfied_link_error_entry(),
 988       !native_bind_event_is_interesting);
 989   }
 990 
 991   // Setup compiler entrypoint.  This is made eagerly, so we do not need
 992   // special handling of vtables.  An alternative is to make adapters more
 993   // lazily by calling make_adapter() from from_compiled_entry() for the
 994   // normal calls.  For vtable calls life gets more complicated.  When a
 995   // call-site goes mega-morphic we need adapters in all methods which can be
 996   // called from the vtable.  We need adapters on such methods that get loaded
 997   // later.  Ditto for mega-morphic itable calls.  If this proves to be a
 998   // problem we'll make these lazily later.
 999   (void) make_adapters(h_method, CHECK);
1000 
1001   // ONLY USE the h_method now as make_adapter may have blocked
1002 
1003 }
1004 
1005 address Method::make_adapters(methodHandle mh, TRAPS) {
1006   // Adapters for compiled code are made eagerly here.  They are fairly
1007   // small (generally < 100 bytes) and quick to make (and cached and shared)
1008   // so making them eagerly shouldn't be too expensive.
1009   AdapterHandlerEntry* adapter = AdapterHandlerLibrary::get_adapter(mh);
1010   if (adapter == NULL ) {
1011     THROW_MSG_NULL(vmSymbols::java_lang_VirtualMachineError(), "Out of space in CodeCache for adapters");
1012   }
1013 
1014   if (mh->is_shared()) {
1015     assert(mh->adapter() == adapter, "must be");
1016     assert(mh->_from_compiled_entry != NULL, "must be"); // FIXME, the instructions also not NULL
1017   } else {
1018     mh->set_adapter_entry(adapter);
1019     mh->_from_compiled_entry = adapter->get_c2i_entry();
1020   }
1021   return adapter->get_c2i_entry();
1022 }
1023 
1024 void Method::restore_unshareable_info(TRAPS) {
1025   // Since restore_unshareable_info can be called more than once for a method, don't
1026   // redo any work.   If this field is restored, there is nothing to do.
1027   if (_from_compiled_entry == NULL) {
1028     // restore method's vtable by calling a virtual function
1029     restore_vtable();
1030 
1031     methodHandle mh(THREAD, this);
1032     link_method(mh, CHECK);
1033   }
1034 }
1035 
1036 volatile address Method::from_compiled_entry_no_trampoline() const {
1037   nmethod *code = (nmethod *)OrderAccess::load_ptr_acquire(&_code);
1038   if (code) {
1039     return code->verified_entry_point();
1040   } else {
1041     return adapter()->get_c2i_entry();
1042   }
1043 }
1044 
1045 // The verified_code_entry() must be called when a invoke is resolved
1046 // on this method.
1047 
1048 // It returns the compiled code entry point, after asserting not null.
1049 // This function is called after potential safepoints so that nmethod
1050 // or adapter that it points to is still live and valid.
1051 // This function must not hit a safepoint!
1052 address Method::verified_code_entry() {
1053   debug_only(NoSafepointVerifier nsv;)
1054   assert(_from_compiled_entry != NULL, "must be set");
1055   return _from_compiled_entry;
1056 }
1057 
1058 // Check that if an nmethod ref exists, it has a backlink to this or no backlink at all
1059 // (could be racing a deopt).
1060 // Not inline to avoid circular ref.
1061 bool Method::check_code() const {
1062   // cached in a register or local.  There's a race on the value of the field.
1063   CompiledMethod *code = (CompiledMethod *)OrderAccess::load_ptr_acquire(&_code);
1064   return code == NULL || (code->method() == NULL) || (code->method() == (Method*)this && !code->is_osr_method());
1065 }
1066 
1067 // Install compiled code.  Instantly it can execute.
1068 void Method::set_code(methodHandle mh, CompiledMethod *code) {
1069   assert( code, "use clear_code to remove code" );
1070   assert( mh->check_code(), "" );
1071 
1072   guarantee(mh->adapter() != NULL, "Adapter blob must already exist!");
1073 
1074   // These writes must happen in this order, because the interpreter will
1075   // directly jump to from_interpreted_entry which jumps to an i2c adapter
1076   // which jumps to _from_compiled_entry.
1077   mh->_code = code;             // Assign before allowing compiled code to exec
1078 
1079   int comp_level = code->comp_level();
1080   // In theory there could be a race here. In practice it is unlikely
1081   // and not worth worrying about.
1082   if (comp_level > mh->highest_comp_level()) {
1083     mh->set_highest_comp_level(comp_level);
1084   }
1085 
1086   OrderAccess::storestore();
1087 #ifdef SHARK
1088   mh->_from_interpreted_entry = code->insts_begin();
1089 #else //!SHARK
1090   mh->_from_compiled_entry = code->verified_entry_point();
1091   OrderAccess::storestore();
1092   // Instantly compiled code can execute.
1093   if (!mh->is_method_handle_intrinsic())
1094     mh->_from_interpreted_entry = mh->get_i2c_entry();
1095 #endif //!SHARK
1096 }
1097 
1098 
1099 bool Method::is_overridden_in(Klass* k) const {
1100   InstanceKlass* ik = InstanceKlass::cast(k);
1101 
1102   if (ik->is_interface()) return false;
1103 
1104   // If method is an interface, we skip it - except if it
1105   // is a miranda method
1106   if (method_holder()->is_interface()) {
1107     // Check that method is not a miranda method
1108     if (ik->lookup_method(name(), signature()) == NULL) {
1109       // No implementation exist - so miranda method
1110       return false;
1111     }
1112     return true;
1113   }
1114 
1115   assert(ik->is_subclass_of(method_holder()), "should be subklass");
1116   assert(ik->vtable() != NULL, "vtable should exist");
1117   if (!has_vtable_index()) {
1118     return false;
1119   } else {
1120     Method* vt_m = ik->method_at_vtable(vtable_index());
1121     return vt_m != this;
1122   }
1123 }
1124 
1125 
1126 // give advice about whether this Method* should be cached or not
1127 bool Method::should_not_be_cached() const {
1128   if (is_old()) {
1129     // This method has been redefined. It is either EMCP or obsolete
1130     // and we don't want to cache it because that would pin the method
1131     // down and prevent it from being collectible if and when it
1132     // finishes executing.
1133     return true;
1134   }
1135 
1136   // caching this method should be just fine
1137   return false;
1138 }
1139 
1140 
1141 /**
1142  *  Returns true if this is one of the specially treated methods for
1143  *  security related stack walks (like Reflection.getCallerClass).
1144  */
1145 bool Method::is_ignored_by_security_stack_walk() const {
1146   if (intrinsic_id() == vmIntrinsics::_invoke) {
1147     // This is Method.invoke() -- ignore it
1148     return true;
1149   }
1150   if (method_holder()->is_subclass_of(SystemDictionary::reflect_MethodAccessorImpl_klass())) {
1151     // This is an auxilary frame -- ignore it
1152     return true;
1153   }
1154   if (is_method_handle_intrinsic() || is_compiled_lambda_form()) {
1155     // This is an internal adapter frame for method handles -- ignore it
1156     return true;
1157   }
1158   return false;
1159 }
1160 
1161 
1162 // Constant pool structure for invoke methods:
1163 enum {
1164   _imcp_invoke_name = 1,        // utf8: 'invokeExact', etc.
1165   _imcp_invoke_signature,       // utf8: (variable Symbol*)
1166   _imcp_limit
1167 };
1168 
1169 // Test if this method is an MH adapter frame generated by Java code.
1170 // Cf. java/lang/invoke/InvokerBytecodeGenerator
1171 bool Method::is_compiled_lambda_form() const {
1172   return intrinsic_id() == vmIntrinsics::_compiledLambdaForm;
1173 }
1174 
1175 // Test if this method is an internal MH primitive method.
1176 bool Method::is_method_handle_intrinsic() const {
1177   vmIntrinsics::ID iid = intrinsic_id();
1178   return (MethodHandles::is_signature_polymorphic(iid) &&
1179           MethodHandles::is_signature_polymorphic_intrinsic(iid));
1180 }
1181 
1182 bool Method::has_member_arg() const {
1183   vmIntrinsics::ID iid = intrinsic_id();
1184   return (MethodHandles::is_signature_polymorphic(iid) &&
1185           MethodHandles::has_member_arg(iid));
1186 }
1187 
1188 // Make an instance of a signature-polymorphic internal MH primitive.
1189 methodHandle Method::make_method_handle_intrinsic(vmIntrinsics::ID iid,
1190                                                          Symbol* signature,
1191                                                          TRAPS) {
1192   ResourceMark rm;
1193   methodHandle empty;
1194 
1195   KlassHandle holder = SystemDictionary::MethodHandle_klass();
1196   Symbol* name = MethodHandles::signature_polymorphic_intrinsic_name(iid);
1197   assert(iid == MethodHandles::signature_polymorphic_name_id(name), "");
1198   if (TraceMethodHandles) {
1199     tty->print_cr("make_method_handle_intrinsic MH.%s%s", name->as_C_string(), signature->as_C_string());
1200   }
1201 
1202   // invariant:   cp->symbol_at_put is preceded by a refcount increment (more usually a lookup)
1203   name->increment_refcount();
1204   signature->increment_refcount();
1205 
1206   int cp_length = _imcp_limit;
1207   ClassLoaderData* loader_data = holder->class_loader_data();
1208   constantPoolHandle cp;
1209   {
1210     ConstantPool* cp_oop = ConstantPool::allocate(loader_data, cp_length, CHECK_(empty));
1211     cp = constantPoolHandle(THREAD, cp_oop);
1212   }
1213   cp->set_pool_holder(InstanceKlass::cast(holder()));
1214   cp->symbol_at_put(_imcp_invoke_name,       name);
1215   cp->symbol_at_put(_imcp_invoke_signature,  signature);
1216   cp->set_has_preresolution();
1217 
1218   // decide on access bits:  public or not?
1219   int flags_bits = (JVM_ACC_NATIVE | JVM_ACC_SYNTHETIC | JVM_ACC_FINAL);
1220   bool must_be_static = MethodHandles::is_signature_polymorphic_static(iid);
1221   if (must_be_static)  flags_bits |= JVM_ACC_STATIC;
1222   assert((flags_bits & JVM_ACC_PUBLIC) == 0, "do not expose these methods");
1223 
1224   methodHandle m;
1225   {
1226     InlineTableSizes sizes;
1227     Method* m_oop = Method::allocate(loader_data, 0,
1228                                      accessFlags_from(flags_bits), &sizes,
1229                                      ConstMethod::NORMAL, CHECK_(empty));
1230     m = methodHandle(THREAD, m_oop);
1231   }
1232   m->set_constants(cp());
1233   m->set_name_index(_imcp_invoke_name);
1234   m->set_signature_index(_imcp_invoke_signature);
1235   assert(MethodHandles::is_signature_polymorphic_name(m->name()), "");
1236   assert(m->signature() == signature, "");
1237   ResultTypeFinder rtf(signature);
1238   m->constMethod()->set_result_type(rtf.type());
1239   m->compute_size_of_parameters(THREAD);
1240   m->init_intrinsic_id();
1241   assert(m->is_method_handle_intrinsic(), "");
1242 #ifdef ASSERT
1243   if (!MethodHandles::is_signature_polymorphic(m->intrinsic_id()))  m->print();
1244   assert(MethodHandles::is_signature_polymorphic(m->intrinsic_id()), "must be an invoker");
1245   assert(m->intrinsic_id() == iid, "correctly predicted iid");
1246 #endif //ASSERT
1247 
1248   // Finally, set up its entry points.
1249   assert(m->can_be_statically_bound(), "");
1250   m->set_vtable_index(Method::nonvirtual_vtable_index);
1251   m->link_method(m, CHECK_(empty));
1252 
1253   if (TraceMethodHandles && (Verbose || WizardMode)) {
1254     ttyLocker ttyl;
1255     m->print_on(tty);
1256   }
1257 
1258   return m;
1259 }
1260 
1261 Klass* Method::check_non_bcp_klass(Klass* klass) {
1262   if (klass != NULL && klass->class_loader() != NULL) {
1263     if (klass->is_objArray_klass())
1264       klass = ObjArrayKlass::cast(klass)->bottom_klass();
1265     return klass;
1266   }
1267   return NULL;
1268 }
1269 
1270 
1271 methodHandle Method::clone_with_new_data(methodHandle m, u_char* new_code, int new_code_length,
1272                                                 u_char* new_compressed_linenumber_table, int new_compressed_linenumber_size, TRAPS) {
1273   // Code below does not work for native methods - they should never get rewritten anyway
1274   assert(!m->is_native(), "cannot rewrite native methods");
1275   // Allocate new Method*
1276   AccessFlags flags = m->access_flags();
1277 
1278   ConstMethod* cm = m->constMethod();
1279   int checked_exceptions_len = cm->checked_exceptions_length();
1280   int localvariable_len = cm->localvariable_table_length();
1281   int exception_table_len = cm->exception_table_length();
1282   int method_parameters_len = cm->method_parameters_length();
1283   int method_annotations_len = cm->method_annotations_length();
1284   int parameter_annotations_len = cm->parameter_annotations_length();
1285   int type_annotations_len = cm->type_annotations_length();
1286   int default_annotations_len = cm->default_annotations_length();
1287 
1288   InlineTableSizes sizes(
1289       localvariable_len,
1290       new_compressed_linenumber_size,
1291       exception_table_len,
1292       checked_exceptions_len,
1293       method_parameters_len,
1294       cm->generic_signature_index(),
1295       method_annotations_len,
1296       parameter_annotations_len,
1297       type_annotations_len,
1298       default_annotations_len,
1299       0);
1300 
1301   ClassLoaderData* loader_data = m->method_holder()->class_loader_data();
1302   Method* newm_oop = Method::allocate(loader_data,
1303                                       new_code_length,
1304                                       flags,
1305                                       &sizes,
1306                                       m->method_type(),
1307                                       CHECK_(methodHandle()));
1308   methodHandle newm (THREAD, newm_oop);
1309 
1310   // Create a shallow copy of Method part, but be careful to preserve the new ConstMethod*
1311   ConstMethod* newcm = newm->constMethod();
1312   int new_const_method_size = newm->constMethod()->size();
1313 
1314   memcpy(newm(), m(), sizeof(Method));
1315 
1316   // Create shallow copy of ConstMethod.
1317   memcpy(newcm, m->constMethod(), sizeof(ConstMethod));
1318 
1319   // Reset correct method/const method, method size, and parameter info
1320   newm->set_constMethod(newcm);
1321   newm->constMethod()->set_code_size(new_code_length);
1322   newm->constMethod()->set_constMethod_size(new_const_method_size);
1323   assert(newm->code_size() == new_code_length, "check");
1324   assert(newm->method_parameters_length() == method_parameters_len, "check");
1325   assert(newm->checked_exceptions_length() == checked_exceptions_len, "check");
1326   assert(newm->exception_table_length() == exception_table_len, "check");
1327   assert(newm->localvariable_table_length() == localvariable_len, "check");
1328   // Copy new byte codes
1329   memcpy(newm->code_base(), new_code, new_code_length);
1330   // Copy line number table
1331   if (new_compressed_linenumber_size > 0) {
1332     memcpy(newm->compressed_linenumber_table(),
1333            new_compressed_linenumber_table,
1334            new_compressed_linenumber_size);
1335   }
1336   // Copy method_parameters
1337   if (method_parameters_len > 0) {
1338     memcpy(newm->method_parameters_start(),
1339            m->method_parameters_start(),
1340            method_parameters_len * sizeof(MethodParametersElement));
1341   }
1342   // Copy checked_exceptions
1343   if (checked_exceptions_len > 0) {
1344     memcpy(newm->checked_exceptions_start(),
1345            m->checked_exceptions_start(),
1346            checked_exceptions_len * sizeof(CheckedExceptionElement));
1347   }
1348   // Copy exception table
1349   if (exception_table_len > 0) {
1350     memcpy(newm->exception_table_start(),
1351            m->exception_table_start(),
1352            exception_table_len * sizeof(ExceptionTableElement));
1353   }
1354   // Copy local variable number table
1355   if (localvariable_len > 0) {
1356     memcpy(newm->localvariable_table_start(),
1357            m->localvariable_table_start(),
1358            localvariable_len * sizeof(LocalVariableTableElement));
1359   }
1360   // Copy stackmap table
1361   if (m->has_stackmap_table()) {
1362     int code_attribute_length = m->stackmap_data()->length();
1363     Array<u1>* stackmap_data =
1364       MetadataFactory::new_array<u1>(loader_data, code_attribute_length, 0, CHECK_NULL);
1365     memcpy((void*)stackmap_data->adr_at(0),
1366            (void*)m->stackmap_data()->adr_at(0), code_attribute_length);
1367     newm->set_stackmap_data(stackmap_data);
1368   }
1369 
1370   // copy annotations over to new method
1371   newcm->copy_annotations_from(cm);
1372   return newm;
1373 }
1374 
1375 vmSymbols::SID Method::klass_id_for_intrinsics(const Klass* holder) {
1376   // if loader is not the default loader (i.e., != NULL), we can't know the intrinsics
1377   // because we are not loading from core libraries
1378   // exception: the AES intrinsics come from lib/ext/sunjce_provider.jar
1379   // which does not use the class default class loader so we check for its loader here
1380   const InstanceKlass* ik = InstanceKlass::cast(holder);
1381   if ((ik->class_loader() != NULL) && !SystemDictionary::is_platform_class_loader(ik->class_loader())) {
1382     return vmSymbols::NO_SID;   // regardless of name, no intrinsics here
1383   }
1384 
1385   // see if the klass name is well-known:
1386   Symbol* klass_name = ik->name();
1387   return vmSymbols::find_sid(klass_name);
1388 }
1389 
1390 void Method::init_intrinsic_id() {
1391   assert(_intrinsic_id == vmIntrinsics::_none, "do this just once");
1392   const uintptr_t max_id_uint = right_n_bits((int)(sizeof(_intrinsic_id) * BitsPerByte));
1393   assert((uintptr_t)vmIntrinsics::ID_LIMIT <= max_id_uint, "else fix size");
1394   assert(intrinsic_id_size_in_bytes() == sizeof(_intrinsic_id), "");
1395 
1396   // the klass name is well-known:
1397   vmSymbols::SID klass_id = klass_id_for_intrinsics(method_holder());
1398   assert(klass_id != vmSymbols::NO_SID, "caller responsibility");
1399 
1400   // ditto for method and signature:
1401   vmSymbols::SID  name_id = vmSymbols::find_sid(name());
1402   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1403       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1404       && name_id == vmSymbols::NO_SID) {
1405     return;
1406   }
1407   vmSymbols::SID   sig_id = vmSymbols::find_sid(signature());
1408   if (klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle)
1409       && klass_id != vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle)
1410       && sig_id == vmSymbols::NO_SID) {
1411     return;
1412   }
1413   jshort flags = access_flags().as_short();
1414 
1415   vmIntrinsics::ID id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1416   if (id != vmIntrinsics::_none) {
1417     set_intrinsic_id(id);
1418     if (id == vmIntrinsics::_Class_cast) {
1419       // Even if the intrinsic is rejected, we want to inline this simple method.
1420       set_force_inline(true);
1421     }
1422     return;
1423   }
1424 
1425   // A few slightly irregular cases:
1426   switch (klass_id) {
1427   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_StrictMath):
1428     // Second chance: check in regular Math.
1429     switch (name_id) {
1430     case vmSymbols::VM_SYMBOL_ENUM_NAME(min_name):
1431     case vmSymbols::VM_SYMBOL_ENUM_NAME(max_name):
1432     case vmSymbols::VM_SYMBOL_ENUM_NAME(sqrt_name):
1433       // pretend it is the corresponding method in the non-strict class:
1434       klass_id = vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_Math);
1435       id = vmIntrinsics::find_id(klass_id, name_id, sig_id, flags);
1436       break;
1437     }
1438     break;
1439 
1440   // Signature-polymorphic methods: MethodHandle.invoke*, InvokeDynamic.*., VarHandle
1441   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_MethodHandle):
1442   case vmSymbols::VM_SYMBOL_ENUM_NAME(java_lang_invoke_VarHandle):
1443     if (!is_native())  break;
1444     id = MethodHandles::signature_polymorphic_name_id(method_holder(), name());
1445     if (is_static() != MethodHandles::is_signature_polymorphic_static(id))
1446       id = vmIntrinsics::_none;
1447     break;
1448   }
1449 
1450   if (id != vmIntrinsics::_none) {
1451     // Set up its iid.  It is an alias method.
1452     set_intrinsic_id(id);
1453     return;
1454   }
1455 }
1456 
1457 // These two methods are static since a GC may move the Method
1458 bool Method::load_signature_classes(methodHandle m, TRAPS) {
1459   if (!THREAD->can_call_java()) {
1460     // There is nothing useful this routine can do from within the Compile thread.
1461     // Hopefully, the signature contains only well-known classes.
1462     // We could scan for this and return true/false, but the caller won't care.
1463     return false;
1464   }
1465   bool sig_is_loaded = true;
1466   Handle class_loader(THREAD, m->method_holder()->class_loader());
1467   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1468   ResourceMark rm(THREAD);
1469   Symbol*  signature = m->signature();
1470   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1471     if (ss.is_object()) {
1472       Symbol* sym = ss.as_symbol(CHECK_(false));
1473       Symbol*  name  = sym;
1474       Klass* klass = SystemDictionary::resolve_or_null(name, class_loader,
1475                                              protection_domain, THREAD);
1476       // We are loading classes eagerly. If a ClassNotFoundException or
1477       // a LinkageError was generated, be sure to ignore it.
1478       if (HAS_PENDING_EXCEPTION) {
1479         if (PENDING_EXCEPTION->is_a(SystemDictionary::ClassNotFoundException_klass()) ||
1480             PENDING_EXCEPTION->is_a(SystemDictionary::LinkageError_klass())) {
1481           CLEAR_PENDING_EXCEPTION;
1482         } else {
1483           return false;
1484         }
1485       }
1486       if( klass == NULL) { sig_is_loaded = false; }
1487     }
1488   }
1489   return sig_is_loaded;
1490 }
1491 
1492 bool Method::has_unloaded_classes_in_signature(methodHandle m, TRAPS) {
1493   Handle class_loader(THREAD, m->method_holder()->class_loader());
1494   Handle protection_domain(THREAD, m->method_holder()->protection_domain());
1495   ResourceMark rm(THREAD);
1496   Symbol*  signature = m->signature();
1497   for(SignatureStream ss(signature); !ss.is_done(); ss.next()) {
1498     if (ss.type() == T_OBJECT) {
1499       Symbol* name = ss.as_symbol_or_null();
1500       if (name == NULL) return true;
1501       Klass* klass = SystemDictionary::find(name, class_loader, protection_domain, THREAD);
1502       if (klass == NULL) return true;
1503     }
1504   }
1505   return false;
1506 }
1507 
1508 // Exposed so field engineers can debug VM
1509 void Method::print_short_name(outputStream* st) {
1510   ResourceMark rm;
1511 #ifdef PRODUCT
1512   st->print(" %s::", method_holder()->external_name());
1513 #else
1514   st->print(" %s::", method_holder()->internal_name());
1515 #endif
1516   name()->print_symbol_on(st);
1517   if (WizardMode) signature()->print_symbol_on(st);
1518   else if (MethodHandles::is_signature_polymorphic(intrinsic_id()))
1519     MethodHandles::print_as_basic_type_signature_on(st, signature(), true);
1520 }
1521 
1522 // Comparer for sorting an object array containing
1523 // Method*s.
1524 static int method_comparator(Method* a, Method* b) {
1525   return a->name()->fast_compare(b->name());
1526 }
1527 
1528 // This is only done during class loading, so it is OK to assume method_idnum matches the methods() array
1529 // default_methods also uses this without the ordering for fast find_method
1530 void Method::sort_methods(Array<Method*>* methods, bool idempotent, bool set_idnums) {
1531   int length = methods->length();
1532   if (length > 1) {
1533     {
1534       NoSafepointVerifier nsv;
1535       QuickSort::sort<Method*>(methods->data(), length, method_comparator, idempotent);
1536     }
1537     // Reset method ordering
1538     if (set_idnums) {
1539       for (int i = 0; i < length; i++) {
1540         Method* m = methods->at(i);
1541         m->set_method_idnum(i);
1542         m->set_orig_method_idnum(i);
1543       }
1544     }
1545   }
1546 }
1547 
1548 //-----------------------------------------------------------------------------------
1549 // Non-product code unless JVM/TI needs it
1550 
1551 #if !defined(PRODUCT) || INCLUDE_JVMTI
1552 class SignatureTypePrinter : public SignatureTypeNames {
1553  private:
1554   outputStream* _st;
1555   bool _use_separator;
1556 
1557   void type_name(const char* name) {
1558     if (_use_separator) _st->print(", ");
1559     _st->print("%s", name);
1560     _use_separator = true;
1561   }
1562 
1563  public:
1564   SignatureTypePrinter(Symbol* signature, outputStream* st) : SignatureTypeNames(signature) {
1565     _st = st;
1566     _use_separator = false;
1567   }
1568 
1569   void print_parameters()              { _use_separator = false; iterate_parameters(); }
1570   void print_returntype()              { _use_separator = false; iterate_returntype(); }
1571 };
1572 
1573 
1574 void Method::print_name(outputStream* st) {
1575   Thread *thread = Thread::current();
1576   ResourceMark rm(thread);
1577   st->print("%s ", is_static() ? "static" : "virtual");
1578   if (WizardMode) {
1579     st->print("%s.", method_holder()->internal_name());
1580     name()->print_symbol_on(st);
1581     signature()->print_symbol_on(st);
1582   } else {
1583     SignatureTypePrinter sig(signature(), st);
1584     sig.print_returntype();
1585     st->print(" %s.", method_holder()->internal_name());
1586     name()->print_symbol_on(st);
1587     st->print("(");
1588     sig.print_parameters();
1589     st->print(")");
1590   }
1591 }
1592 #endif // !PRODUCT || INCLUDE_JVMTI
1593 
1594 
1595 void Method::print_codes_on(outputStream* st) const {
1596   print_codes_on(0, code_size(), st);
1597 }
1598 
1599 void Method::print_codes_on(int from, int to, outputStream* st) const {
1600   Thread *thread = Thread::current();
1601   ResourceMark rm(thread);
1602   methodHandle mh (thread, (Method*)this);
1603   BytecodeStream s(mh);
1604   s.set_interval(from, to);
1605   BytecodeTracer::set_closure(BytecodeTracer::std_closure());
1606   while (s.next() >= 0) BytecodeTracer::trace(mh, s.bcp(), st);
1607 }
1608 
1609 
1610 // Simple compression of line number tables. We use a regular compressed stream, except that we compress deltas
1611 // between (bci,line) pairs since they are smaller. If (bci delta, line delta) fits in (5-bit unsigned, 3-bit unsigned)
1612 // we save it as one byte, otherwise we write a 0xFF escape character and use regular compression. 0x0 is used
1613 // as end-of-stream terminator.
1614 
1615 void CompressedLineNumberWriteStream::write_pair_regular(int bci_delta, int line_delta) {
1616   // bci and line number does not compress into single byte.
1617   // Write out escape character and use regular compression for bci and line number.
1618   write_byte((jubyte)0xFF);
1619   write_signed_int(bci_delta);
1620   write_signed_int(line_delta);
1621 }
1622 
1623 // See comment in method.hpp which explains why this exists.
1624 #if defined(_M_AMD64) && _MSC_VER >= 1400
1625 #pragma optimize("", off)
1626 void CompressedLineNumberWriteStream::write_pair(int bci, int line) {
1627   write_pair_inline(bci, line);
1628 }
1629 #pragma optimize("", on)
1630 #endif
1631 
1632 CompressedLineNumberReadStream::CompressedLineNumberReadStream(u_char* buffer) : CompressedReadStream(buffer) {
1633   _bci = 0;
1634   _line = 0;
1635 };
1636 
1637 
1638 bool CompressedLineNumberReadStream::read_pair() {
1639   jubyte next = read_byte();
1640   // Check for terminator
1641   if (next == 0) return false;
1642   if (next == 0xFF) {
1643     // Escape character, regular compression used
1644     _bci  += read_signed_int();
1645     _line += read_signed_int();
1646   } else {
1647     // Single byte compression used
1648     _bci  += next >> 3;
1649     _line += next & 0x7;
1650   }
1651   return true;
1652 }
1653 
1654 #if INCLUDE_JVMTI
1655 
1656 Bytecodes::Code Method::orig_bytecode_at(int bci) const {
1657   BreakpointInfo* bp = method_holder()->breakpoints();
1658   for (; bp != NULL; bp = bp->next()) {
1659     if (bp->match(this, bci)) {
1660       return bp->orig_bytecode();
1661     }
1662   }
1663   {
1664     ResourceMark rm;
1665     fatal("no original bytecode found in %s at bci %d", name_and_sig_as_C_string(), bci);
1666   }
1667   return Bytecodes::_shouldnotreachhere;
1668 }
1669 
1670 void Method::set_orig_bytecode_at(int bci, Bytecodes::Code code) {
1671   assert(code != Bytecodes::_breakpoint, "cannot patch breakpoints this way");
1672   BreakpointInfo* bp = method_holder()->breakpoints();
1673   for (; bp != NULL; bp = bp->next()) {
1674     if (bp->match(this, bci)) {
1675       bp->set_orig_bytecode(code);
1676       // and continue, in case there is more than one
1677     }
1678   }
1679 }
1680 
1681 void Method::set_breakpoint(int bci) {
1682   InstanceKlass* ik = method_holder();
1683   BreakpointInfo *bp = new BreakpointInfo(this, bci);
1684   bp->set_next(ik->breakpoints());
1685   ik->set_breakpoints(bp);
1686   // do this last:
1687   bp->set(this);
1688 }
1689 
1690 static void clear_matches(Method* m, int bci) {
1691   InstanceKlass* ik = m->method_holder();
1692   BreakpointInfo* prev_bp = NULL;
1693   BreakpointInfo* next_bp;
1694   for (BreakpointInfo* bp = ik->breakpoints(); bp != NULL; bp = next_bp) {
1695     next_bp = bp->next();
1696     // bci value of -1 is used to delete all breakpoints in method m (ex: clear_all_breakpoint).
1697     if (bci >= 0 ? bp->match(m, bci) : bp->match(m)) {
1698       // do this first:
1699       bp->clear(m);
1700       // unhook it
1701       if (prev_bp != NULL)
1702         prev_bp->set_next(next_bp);
1703       else
1704         ik->set_breakpoints(next_bp);
1705       delete bp;
1706       // When class is redefined JVMTI sets breakpoint in all versions of EMCP methods
1707       // at same location. So we have multiple matching (method_index and bci)
1708       // BreakpointInfo nodes in BreakpointInfo list. We should just delete one
1709       // breakpoint for clear_breakpoint request and keep all other method versions
1710       // BreakpointInfo for future clear_breakpoint request.
1711       // bcivalue of -1 is used to clear all breakpoints (see clear_all_breakpoints)
1712       // which is being called when class is unloaded. We delete all the Breakpoint
1713       // information for all versions of method. We may not correctly restore the original
1714       // bytecode in all method versions, but that is ok. Because the class is being unloaded
1715       // so these methods won't be used anymore.
1716       if (bci >= 0) {
1717         break;
1718       }
1719     } else {
1720       // This one is a keeper.
1721       prev_bp = bp;
1722     }
1723   }
1724 }
1725 
1726 void Method::clear_breakpoint(int bci) {
1727   assert(bci >= 0, "");
1728   clear_matches(this, bci);
1729 }
1730 
1731 void Method::clear_all_breakpoints() {
1732   clear_matches(this, -1);
1733 }
1734 
1735 #endif // INCLUDE_JVMTI
1736 
1737 int Method::invocation_count() {
1738   MethodCounters *mcs = method_counters();
1739   if (TieredCompilation) {
1740     MethodData* const mdo = method_data();
1741     if (((mcs != NULL) ? mcs->invocation_counter()->carry() : false) ||
1742         ((mdo != NULL) ? mdo->invocation_counter()->carry() : false)) {
1743       return InvocationCounter::count_limit;
1744     } else {
1745       return ((mcs != NULL) ? mcs->invocation_counter()->count() : 0) +
1746              ((mdo != NULL) ? mdo->invocation_counter()->count() : 0);
1747     }
1748   } else {
1749     return (mcs == NULL) ? 0 : mcs->invocation_counter()->count();
1750   }
1751 }
1752 
1753 int Method::backedge_count() {
1754   MethodCounters *mcs = method_counters();
1755   if (TieredCompilation) {
1756     MethodData* const mdo = method_data();
1757     if (((mcs != NULL) ? mcs->backedge_counter()->carry() : false) ||
1758         ((mdo != NULL) ? mdo->backedge_counter()->carry() : false)) {
1759       return InvocationCounter::count_limit;
1760     } else {
1761       return ((mcs != NULL) ? mcs->backedge_counter()->count() : 0) +
1762              ((mdo != NULL) ? mdo->backedge_counter()->count() : 0);
1763     }
1764   } else {
1765     return (mcs == NULL) ? 0 : mcs->backedge_counter()->count();
1766   }
1767 }
1768 
1769 int Method::highest_comp_level() const {
1770   const MethodCounters* mcs = method_counters();
1771   if (mcs != NULL) {
1772     return mcs->highest_comp_level();
1773   } else {
1774     return CompLevel_none;
1775   }
1776 }
1777 
1778 int Method::highest_osr_comp_level() const {
1779   const MethodCounters* mcs = method_counters();
1780   if (mcs != NULL) {
1781     return mcs->highest_osr_comp_level();
1782   } else {
1783     return CompLevel_none;
1784   }
1785 }
1786 
1787 void Method::set_highest_comp_level(int level) {
1788   MethodCounters* mcs = method_counters();
1789   if (mcs != NULL) {
1790     mcs->set_highest_comp_level(level);
1791   }
1792 }
1793 
1794 void Method::set_highest_osr_comp_level(int level) {
1795   MethodCounters* mcs = method_counters();
1796   if (mcs != NULL) {
1797     mcs->set_highest_osr_comp_level(level);
1798   }
1799 }
1800 
1801 #if INCLUDE_JVMTI
1802 
1803 BreakpointInfo::BreakpointInfo(Method* m, int bci) {
1804   _bci = bci;
1805   _name_index = m->name_index();
1806   _signature_index = m->signature_index();
1807   _orig_bytecode = (Bytecodes::Code) *m->bcp_from(_bci);
1808   if (_orig_bytecode == Bytecodes::_breakpoint)
1809     _orig_bytecode = m->orig_bytecode_at(_bci);
1810   _next = NULL;
1811 }
1812 
1813 void BreakpointInfo::set(Method* method) {
1814 #ifdef ASSERT
1815   {
1816     Bytecodes::Code code = (Bytecodes::Code) *method->bcp_from(_bci);
1817     if (code == Bytecodes::_breakpoint)
1818       code = method->orig_bytecode_at(_bci);
1819     assert(orig_bytecode() == code, "original bytecode must be the same");
1820   }
1821 #endif
1822   Thread *thread = Thread::current();
1823   *method->bcp_from(_bci) = Bytecodes::_breakpoint;
1824   method->incr_number_of_breakpoints(thread);
1825   SystemDictionary::notice_modification();
1826   {
1827     // Deoptimize all dependents on this method
1828     HandleMark hm(thread);
1829     methodHandle mh(thread, method);
1830     CodeCache::flush_dependents_on_method(mh);
1831   }
1832 }
1833 
1834 void BreakpointInfo::clear(Method* method) {
1835   *method->bcp_from(_bci) = orig_bytecode();
1836   assert(method->number_of_breakpoints() > 0, "must not go negative");
1837   method->decr_number_of_breakpoints(Thread::current());
1838 }
1839 
1840 #endif // INCLUDE_JVMTI
1841 
1842 // jmethodID handling
1843 
1844 // This is a block allocating object, sort of like JNIHandleBlock, only a
1845 // lot simpler.
1846 // It's allocated on the CHeap because once we allocate a jmethodID, we can
1847 // never get rid of it.
1848 
1849 static const int min_block_size = 8;
1850 
1851 class JNIMethodBlockNode : public CHeapObj<mtClass> {
1852   friend class JNIMethodBlock;
1853   Method**        _methods;
1854   int             _number_of_methods;
1855   int             _top;
1856   JNIMethodBlockNode* _next;
1857 
1858  public:
1859 
1860   JNIMethodBlockNode(int num_methods = min_block_size);
1861 
1862   ~JNIMethodBlockNode() { FREE_C_HEAP_ARRAY(Method*, _methods); }
1863 
1864   void ensure_methods(int num_addl_methods) {
1865     if (_top < _number_of_methods) {
1866       num_addl_methods -= _number_of_methods - _top;
1867       if (num_addl_methods <= 0) {
1868         return;
1869       }
1870     }
1871     if (_next == NULL) {
1872       _next = new JNIMethodBlockNode(MAX2(num_addl_methods, min_block_size));
1873     } else {
1874       _next->ensure_methods(num_addl_methods);
1875     }
1876   }
1877 };
1878 
1879 class JNIMethodBlock : public CHeapObj<mtClass> {
1880   JNIMethodBlockNode _head;
1881   JNIMethodBlockNode *_last_free;
1882  public:
1883   static Method* const _free_method;
1884 
1885   JNIMethodBlock(int initial_capacity = min_block_size)
1886       : _head(initial_capacity), _last_free(&_head) {}
1887 
1888   void ensure_methods(int num_addl_methods) {
1889     _last_free->ensure_methods(num_addl_methods);
1890   }
1891 
1892   Method** add_method(Method* m) {
1893     for (JNIMethodBlockNode* b = _last_free; b != NULL; b = b->_next) {
1894       if (b->_top < b->_number_of_methods) {
1895         // top points to the next free entry.
1896         int i = b->_top;
1897         b->_methods[i] = m;
1898         b->_top++;
1899         _last_free = b;
1900         return &(b->_methods[i]);
1901       } else if (b->_top == b->_number_of_methods) {
1902         // if the next free entry ran off the block see if there's a free entry
1903         for (int i = 0; i < b->_number_of_methods; i++) {
1904           if (b->_methods[i] == _free_method) {
1905             b->_methods[i] = m;
1906             _last_free = b;
1907             return &(b->_methods[i]);
1908           }
1909         }
1910         // Only check each block once for frees.  They're very unlikely.
1911         // Increment top past the end of the block.
1912         b->_top++;
1913       }
1914       // need to allocate a next block.
1915       if (b->_next == NULL) {
1916         b->_next = _last_free = new JNIMethodBlockNode();
1917       }
1918     }
1919     guarantee(false, "Should always allocate a free block");
1920     return NULL;
1921   }
1922 
1923   bool contains(Method** m) {
1924     if (m == NULL) return false;
1925     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1926       if (b->_methods <= m && m < b->_methods + b->_number_of_methods) {
1927         // This is a bit of extra checking, for two reasons.  One is
1928         // that contains() deals with pointers that are passed in by
1929         // JNI code, so making sure that the pointer is aligned
1930         // correctly is valuable.  The other is that <= and > are
1931         // technically not defined on pointers, so the if guard can
1932         // pass spuriously; no modern compiler is likely to make that
1933         // a problem, though (and if one did, the guard could also
1934         // fail spuriously, which would be bad).
1935         ptrdiff_t idx = m - b->_methods;
1936         if (b->_methods + idx == m) {
1937           return true;
1938         }
1939       }
1940     }
1941     return false;  // not found
1942   }
1943 
1944   // Doesn't really destroy it, just marks it as free so it can be reused.
1945   void destroy_method(Method** m) {
1946 #ifdef ASSERT
1947     assert(contains(m), "should be a methodID");
1948 #endif // ASSERT
1949     *m = _free_method;
1950   }
1951 
1952   // During class unloading the methods are cleared, which is different
1953   // than freed.
1954   void clear_all_methods() {
1955     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1956       for (int i = 0; i< b->_number_of_methods; i++) {
1957         b->_methods[i] = NULL;
1958       }
1959     }
1960   }
1961 #ifndef PRODUCT
1962   int count_methods() {
1963     // count all allocated methods
1964     int count = 0;
1965     for (JNIMethodBlockNode* b = &_head; b != NULL; b = b->_next) {
1966       for (int i = 0; i< b->_number_of_methods; i++) {
1967         if (b->_methods[i] != _free_method) count++;
1968       }
1969     }
1970     return count;
1971   }
1972 #endif // PRODUCT
1973 };
1974 
1975 // Something that can't be mistaken for an address or a markOop
1976 Method* const JNIMethodBlock::_free_method = (Method*)55;
1977 
1978 JNIMethodBlockNode::JNIMethodBlockNode(int num_methods) : _next(NULL), _top(0) {
1979   _number_of_methods = MAX2(num_methods, min_block_size);
1980   _methods = NEW_C_HEAP_ARRAY(Method*, _number_of_methods, mtInternal);
1981   for (int i = 0; i < _number_of_methods; i++) {
1982     _methods[i] = JNIMethodBlock::_free_method;
1983   }
1984 }
1985 
1986 void Method::ensure_jmethod_ids(ClassLoaderData* loader_data, int capacity) {
1987   ClassLoaderData* cld = loader_data;
1988   if (!SafepointSynchronize::is_at_safepoint()) {
1989     // Have to add jmethod_ids() to class loader data thread-safely.
1990     // Also have to add the method to the list safely, which the cld lock
1991     // protects as well.
1992     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
1993     if (cld->jmethod_ids() == NULL) {
1994       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
1995     } else {
1996       cld->jmethod_ids()->ensure_methods(capacity);
1997     }
1998   } else {
1999     // At safepoint, we are single threaded and can set this.
2000     if (cld->jmethod_ids() == NULL) {
2001       cld->set_jmethod_ids(new JNIMethodBlock(capacity));
2002     } else {
2003       cld->jmethod_ids()->ensure_methods(capacity);
2004     }
2005   }
2006 }
2007 
2008 // Add a method id to the jmethod_ids
2009 jmethodID Method::make_jmethod_id(ClassLoaderData* loader_data, Method* m) {
2010   ClassLoaderData* cld = loader_data;
2011 
2012   if (!SafepointSynchronize::is_at_safepoint()) {
2013     // Have to add jmethod_ids() to class loader data thread-safely.
2014     // Also have to add the method to the list safely, which the cld lock
2015     // protects as well.
2016     MutexLockerEx ml(cld->metaspace_lock(),  Mutex::_no_safepoint_check_flag);
2017     if (cld->jmethod_ids() == NULL) {
2018       cld->set_jmethod_ids(new JNIMethodBlock());
2019     }
2020     // jmethodID is a pointer to Method*
2021     return (jmethodID)cld->jmethod_ids()->add_method(m);
2022   } else {
2023     // At safepoint, we are single threaded and can set this.
2024     if (cld->jmethod_ids() == NULL) {
2025       cld->set_jmethod_ids(new JNIMethodBlock());
2026     }
2027     // jmethodID is a pointer to Method*
2028     return (jmethodID)cld->jmethod_ids()->add_method(m);
2029   }
2030 }
2031 
2032 // Mark a jmethodID as free.  This is called when there is a data race in
2033 // InstanceKlass while creating the jmethodID cache.
2034 void Method::destroy_jmethod_id(ClassLoaderData* loader_data, jmethodID m) {
2035   ClassLoaderData* cld = loader_data;
2036   Method** ptr = (Method**)m;
2037   assert(cld->jmethod_ids() != NULL, "should have method handles");
2038   cld->jmethod_ids()->destroy_method(ptr);
2039 }
2040 
2041 void Method::change_method_associated_with_jmethod_id(jmethodID jmid, Method* new_method) {
2042   // Can't assert the method_holder is the same because the new method has the
2043   // scratch method holder.
2044   assert(resolve_jmethod_id(jmid)->method_holder()->class_loader()
2045            == new_method->method_holder()->class_loader(),
2046          "changing to a different class loader");
2047   // Just change the method in place, jmethodID pointer doesn't change.
2048   *((Method**)jmid) = new_method;
2049 }
2050 
2051 bool Method::is_method_id(jmethodID mid) {
2052   Method* m = resolve_jmethod_id(mid);
2053   assert(m != NULL, "should be called with non-null method");
2054   InstanceKlass* ik = m->method_holder();
2055   ClassLoaderData* cld = ik->class_loader_data();
2056   if (cld->jmethod_ids() == NULL) return false;
2057   return (cld->jmethod_ids()->contains((Method**)mid));
2058 }
2059 
2060 Method* Method::checked_resolve_jmethod_id(jmethodID mid) {
2061   if (mid == NULL) return NULL;
2062   Method* o = resolve_jmethod_id(mid);
2063   if (o == NULL || o == JNIMethodBlock::_free_method || !((Metadata*)o)->is_method()) {
2064     return NULL;
2065   }
2066   return o;
2067 };
2068 
2069 void Method::set_on_stack(const bool value) {
2070   // Set both the method itself and its constant pool.  The constant pool
2071   // on stack means some method referring to it is also on the stack.
2072   constants()->set_on_stack(value);
2073 
2074   bool already_set = on_stack();
2075   _access_flags.set_on_stack(value);
2076   if (value && !already_set) {
2077     MetadataOnStackMark::record(this);
2078   }
2079 }
2080 
2081 // Called when the class loader is unloaded to make all methods weak.
2082 void Method::clear_jmethod_ids(ClassLoaderData* loader_data) {
2083   loader_data->jmethod_ids()->clear_all_methods();
2084 }
2085 
2086 bool Method::has_method_vptr(const void* ptr) {
2087   Method m;
2088   // This assumes that the vtbl pointer is the first word of a C++ object.
2089   // This assumption is also in universe.cpp patch_klass_vtble
2090   return dereference_vptr(&m) == dereference_vptr(ptr);
2091 }
2092 
2093 // Check that this pointer is valid by checking that the vtbl pointer matches
2094 bool Method::is_valid_method() const {
2095   if (this == NULL) {
2096     return false;
2097   } else if ((intptr_t(this) & (wordSize-1)) != 0) {
2098     // Quick sanity check on pointer.
2099     return false;
2100   } else if (!is_metaspace_object()) {
2101     return false;
2102   } else {
2103     return has_method_vptr((const void*)this);
2104   }
2105 }
2106 
2107 #ifndef PRODUCT
2108 void Method::print_jmethod_ids(ClassLoaderData* loader_data, outputStream* out) {
2109   out->print_cr("jni_method_id count = %d", loader_data->jmethod_ids()->count_methods());
2110 }
2111 #endif // PRODUCT
2112 
2113 
2114 // Printing
2115 
2116 #ifndef PRODUCT
2117 
2118 void Method::print_on(outputStream* st) const {
2119   ResourceMark rm;
2120   assert(is_method(), "must be method");
2121   st->print_cr("%s", internal_name());
2122   // get the effect of PrintOopAddress, always, for methods:
2123   st->print_cr(" - this oop:          " INTPTR_FORMAT, p2i(this));
2124   st->print   (" - method holder:     "); method_holder()->print_value_on(st); st->cr();
2125   st->print   (" - constants:         " INTPTR_FORMAT " ", p2i(constants()));
2126   constants()->print_value_on(st); st->cr();
2127   st->print   (" - access:            0x%x  ", access_flags().as_int()); access_flags().print_on(st); st->cr();
2128   st->print   (" - name:              ");    name()->print_value_on(st); st->cr();
2129   st->print   (" - signature:         ");    signature()->print_value_on(st); st->cr();
2130   st->print_cr(" - max stack:         %d",   max_stack());
2131   st->print_cr(" - max locals:        %d",   max_locals());
2132   st->print_cr(" - size of params:    %d",   size_of_parameters());
2133   st->print_cr(" - method size:       %d",   method_size());
2134   if (intrinsic_id() != vmIntrinsics::_none)
2135     st->print_cr(" - intrinsic id:      %d %s", intrinsic_id(), vmIntrinsics::name_at(intrinsic_id()));
2136   if (highest_comp_level() != CompLevel_none)
2137     st->print_cr(" - highest level:     %d", highest_comp_level());
2138   st->print_cr(" - vtable index:      %d",   _vtable_index);
2139   st->print_cr(" - i2i entry:         " INTPTR_FORMAT, p2i(interpreter_entry()));
2140   st->print(   " - adapters:          ");
2141   AdapterHandlerEntry* a = ((Method*)this)->adapter();
2142   if (a == NULL)
2143     st->print_cr(INTPTR_FORMAT, p2i(a));
2144   else
2145     a->print_adapter_on(st);
2146   st->print_cr(" - compiled entry     " INTPTR_FORMAT, p2i(from_compiled_entry()));
2147   st->print_cr(" - code size:         %d",   code_size());
2148   if (code_size() != 0) {
2149     st->print_cr(" - code start:        " INTPTR_FORMAT, p2i(code_base()));
2150     st->print_cr(" - code end (excl):   " INTPTR_FORMAT, p2i(code_base() + code_size()));
2151   }
2152   if (method_data() != NULL) {
2153     st->print_cr(" - method data:       " INTPTR_FORMAT, p2i(method_data()));
2154   }
2155   st->print_cr(" - checked ex length: %d",   checked_exceptions_length());
2156   if (checked_exceptions_length() > 0) {
2157     CheckedExceptionElement* table = checked_exceptions_start();
2158     st->print_cr(" - checked ex start:  " INTPTR_FORMAT, p2i(table));
2159     if (Verbose) {
2160       for (int i = 0; i < checked_exceptions_length(); i++) {
2161         st->print_cr("   - throws %s", constants()->printable_name_at(table[i].class_cp_index));
2162       }
2163     }
2164   }
2165   if (has_linenumber_table()) {
2166     u_char* table = compressed_linenumber_table();
2167     st->print_cr(" - linenumber start:  " INTPTR_FORMAT, p2i(table));
2168     if (Verbose) {
2169       CompressedLineNumberReadStream stream(table);
2170       while (stream.read_pair()) {
2171         st->print_cr("   - line %d: %d", stream.line(), stream.bci());
2172       }
2173     }
2174   }
2175   st->print_cr(" - localvar length:   %d",   localvariable_table_length());
2176   if (localvariable_table_length() > 0) {
2177     LocalVariableTableElement* table = localvariable_table_start();
2178     st->print_cr(" - localvar start:    " INTPTR_FORMAT, p2i(table));
2179     if (Verbose) {
2180       for (int i = 0; i < localvariable_table_length(); i++) {
2181         int bci = table[i].start_bci;
2182         int len = table[i].length;
2183         const char* name = constants()->printable_name_at(table[i].name_cp_index);
2184         const char* desc = constants()->printable_name_at(table[i].descriptor_cp_index);
2185         int slot = table[i].slot;
2186         st->print_cr("   - %s %s bci=%d len=%d slot=%d", desc, name, bci, len, slot);
2187       }
2188     }
2189   }
2190   if (code() != NULL) {
2191     st->print   (" - compiled code: ");
2192     code()->print_value_on(st);
2193   }
2194   if (is_native()) {
2195     st->print_cr(" - native function:   " INTPTR_FORMAT, p2i(native_function()));
2196     st->print_cr(" - signature handler: " INTPTR_FORMAT, p2i(signature_handler()));
2197   }
2198 }
2199 
2200 void Method::print_linkage_flags(outputStream* st) {
2201   access_flags().print_on(st);
2202   if (is_default_method()) {
2203     st->print("default ");
2204   }
2205   if (is_overpass()) {
2206     st->print("overpass ");
2207   }
2208 }
2209 #endif //PRODUCT
2210 
2211 void Method::print_value_on(outputStream* st) const {
2212   assert(is_method(), "must be method");
2213   st->print("%s", internal_name());
2214   print_address_on(st);
2215   st->print(" ");
2216   name()->print_value_on(st);
2217   st->print(" ");
2218   signature()->print_value_on(st);
2219   st->print(" in ");
2220   method_holder()->print_value_on(st);
2221   if (WizardMode) st->print("#%d", _vtable_index);
2222   if (WizardMode) st->print("[%d,%d]", size_of_parameters(), max_locals());
2223   if (WizardMode && code() != NULL) st->print(" ((nmethod*)%p)", code());
2224 }
2225 
2226 #if INCLUDE_SERVICES
2227 // Size Statistics
2228 void Method::collect_statistics(KlassSizeStats *sz) const {
2229   int mysize = sz->count(this);
2230   sz->_method_bytes += mysize;
2231   sz->_method_all_bytes += mysize;
2232   sz->_rw_bytes += mysize;
2233 
2234   if (constMethod()) {
2235     constMethod()->collect_statistics(sz);
2236   }
2237   if (method_data()) {
2238     method_data()->collect_statistics(sz);
2239   }
2240 }
2241 #endif // INCLUDE_SERVICES
2242 
2243 // LogTouchedMethods and PrintTouchedMethods
2244 
2245 // TouchedMethodRecord -- we can't use a HashtableEntry<Method*> because
2246 // the Method may be garbage collected. Let's roll our own hash table.
2247 class TouchedMethodRecord : CHeapObj<mtTracing> {
2248 public:
2249   // It's OK to store Symbols here because they will NOT be GC'ed if
2250   // LogTouchedMethods is enabled.
2251   TouchedMethodRecord* _next;
2252   Symbol* _class_name;
2253   Symbol* _method_name;
2254   Symbol* _method_signature;
2255 };
2256 
2257 static const int TOUCHED_METHOD_TABLE_SIZE = 20011;
2258 static TouchedMethodRecord** _touched_method_table = NULL;
2259 
2260 void Method::log_touched(TRAPS) {
2261 
2262   const int table_size = TOUCHED_METHOD_TABLE_SIZE;
2263   Symbol* my_class = klass_name();
2264   Symbol* my_name  = name();
2265   Symbol* my_sig   = signature();
2266 
2267   unsigned int hash = my_class->identity_hash() +
2268                       my_name->identity_hash() +
2269                       my_sig->identity_hash();
2270   juint index = juint(hash) % table_size;
2271 
2272   MutexLocker ml(TouchedMethodLog_lock, THREAD);
2273   if (_touched_method_table == NULL) {
2274     _touched_method_table = NEW_C_HEAP_ARRAY2(TouchedMethodRecord*, table_size,
2275                                               mtTracing, CURRENT_PC);
2276     memset(_touched_method_table, 0, sizeof(TouchedMethodRecord*)*table_size);
2277   }
2278 
2279   TouchedMethodRecord* ptr = _touched_method_table[index];
2280   while (ptr) {
2281     if (ptr->_class_name       == my_class &&
2282         ptr->_method_name      == my_name &&
2283         ptr->_method_signature == my_sig) {
2284       return;
2285     }
2286     if (ptr->_next == NULL) break;
2287     ptr = ptr->_next;
2288   }
2289   TouchedMethodRecord* nptr = NEW_C_HEAP_OBJ(TouchedMethodRecord, mtTracing);
2290   my_class->set_permanent();  // prevent reclaimed by GC
2291   my_name->set_permanent();
2292   my_sig->set_permanent();
2293   nptr->_class_name         = my_class;
2294   nptr->_method_name        = my_name;
2295   nptr->_method_signature   = my_sig;
2296   nptr->_next               = NULL;
2297 
2298   if (ptr == NULL) {
2299     // first
2300     _touched_method_table[index] = nptr;
2301   } else {
2302     ptr->_next = nptr;
2303   }
2304 }
2305 
2306 void Method::print_touched_methods(outputStream* out) {
2307   MutexLockerEx ml(Thread::current()->is_VM_thread() ? NULL : TouchedMethodLog_lock);
2308   out->print_cr("# Method::print_touched_methods version 1");
2309   if (_touched_method_table) {
2310     for (int i = 0; i < TOUCHED_METHOD_TABLE_SIZE; i++) {
2311       TouchedMethodRecord* ptr = _touched_method_table[i];
2312       while(ptr) {
2313         ptr->_class_name->print_symbol_on(out);       out->print(".");
2314         ptr->_method_name->print_symbol_on(out);      out->print(":");
2315         ptr->_method_signature->print_symbol_on(out); out->cr();
2316         ptr = ptr->_next;
2317       }
2318     }
2319   }
2320 }
2321 
2322 // Verification
2323 
2324 void Method::verify_on(outputStream* st) {
2325   guarantee(is_method(), "object must be method");
2326   guarantee(constants()->is_constantPool(), "should be constant pool");
2327   guarantee(constMethod()->is_constMethod(), "should be ConstMethod*");
2328   MethodData* md = method_data();
2329   guarantee(md == NULL ||
2330       md->is_methodData(), "should be method data");
2331 }