1 /*
   2  * Copyright (c) 1998, 2019, 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 "jvm.h"
  27 #include "classfile/classFileStream.hpp"
  28 #include "classfile/classLoader.hpp"
  29 #include "classfile/javaClasses.hpp"
  30 #include "classfile/stackMapTable.hpp"
  31 #include "classfile/stackMapFrame.hpp"
  32 #include "classfile/stackMapTableFormat.hpp"
  33 #include "classfile/symbolTable.hpp"
  34 #include "classfile/systemDictionary.hpp"
  35 #include "classfile/verifier.hpp"
  36 #include "classfile/vmSymbols.hpp"
  37 #include "interpreter/bytecodes.hpp"
  38 #include "interpreter/bytecodeStream.hpp"
  39 #include "logging/log.hpp"
  40 #include "logging/logStream.hpp"
  41 #include "memory/oopFactory.hpp"
  42 #include "memory/resourceArea.hpp"
  43 #include "memory/universe.hpp"
  44 #include "oops/constantPool.inline.hpp"
  45 #include "oops/instanceKlass.hpp"
  46 #include "oops/oop.inline.hpp"
  47 #include "oops/typeArrayOop.hpp"
  48 #include "runtime/fieldDescriptor.hpp"
  49 #include "runtime/handles.inline.hpp"
  50 #include "runtime/interfaceSupport.inline.hpp"
  51 #include "runtime/javaCalls.hpp"
  52 #include "runtime/jniHandles.inline.hpp"
  53 #include "runtime/orderAccess.hpp"
  54 #include "runtime/os.hpp"
  55 #include "runtime/safepointVerifiers.hpp"
  56 #include "runtime/thread.hpp"
  57 #include "services/threadService.hpp"
  58 #include "utilities/align.hpp"
  59 #include "utilities/bytes.hpp"
  60 
  61 #define NOFAILOVER_MAJOR_VERSION                       51
  62 #define NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION  51
  63 #define STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION       52
  64 #define MAX_ARRAY_DIMENSIONS 255
  65 
  66 // Access to external entry for VerifyClassCodes - old byte code verifier
  67 
  68 extern "C" {
  69   typedef jboolean (*verify_byte_codes_fn_t)(JNIEnv *, jclass, char *, jint);
  70   typedef jboolean (*verify_byte_codes_fn_new_t)(JNIEnv *, jclass, char *, jint, jint);
  71 }
  72 
  73 static void* volatile _verify_byte_codes_fn = NULL;
  74 
  75 static volatile jint _is_new_verify_byte_codes_fn = (jint) true;
  76 
  77 static void* verify_byte_codes_fn() {
  78   if (OrderAccess::load_acquire(&_verify_byte_codes_fn) == NULL) {
  79     void *lib_handle = os::native_java_library();
  80     void *func = os::dll_lookup(lib_handle, "VerifyClassCodesForMajorVersion");
  81     OrderAccess::release_store(&_verify_byte_codes_fn, func);
  82     if (func == NULL) {
  83       _is_new_verify_byte_codes_fn = false;
  84       func = os::dll_lookup(lib_handle, "VerifyClassCodes");
  85       OrderAccess::release_store(&_verify_byte_codes_fn, func);
  86     }
  87   }
  88   return (void*)_verify_byte_codes_fn;
  89 }
  90 
  91 
  92 // Methods in Verifier
  93 
  94 bool Verifier::should_verify_for(oop class_loader, bool should_verify_class) {
  95   return (class_loader == NULL || !should_verify_class) ?
  96     BytecodeVerificationLocal : BytecodeVerificationRemote;
  97 }
  98 
  99 bool Verifier::relax_access_for(oop loader) {
 100   bool trusted = java_lang_ClassLoader::is_trusted_loader(loader);
 101   bool need_verify =
 102     // verifyAll
 103     (BytecodeVerificationLocal && BytecodeVerificationRemote) ||
 104     // verifyRemote
 105     (!BytecodeVerificationLocal && BytecodeVerificationRemote && !trusted);
 106   return !need_verify;
 107 }
 108 
 109 void Verifier::trace_class_resolution(Klass* resolve_class, InstanceKlass* verify_class) {
 110   assert(verify_class != NULL, "Unexpected null verify_class");
 111   ResourceMark rm;
 112   Symbol* s = verify_class->source_file_name();
 113   const char* source_file = (s != NULL ? s->as_C_string() : NULL);
 114   const char* verify = verify_class->external_name();
 115   const char* resolve = resolve_class->external_name();
 116   // print in a single call to reduce interleaving between threads
 117   if (source_file != NULL) {
 118     log_debug(class, resolve)("%s %s %s (verification)", verify, resolve, source_file);
 119   } else {
 120     log_debug(class, resolve)("%s %s (verification)", verify, resolve);
 121   }
 122 }
 123 
 124 // Prints the end-verification message to the appropriate output.
 125 void Verifier::log_end_verification(outputStream* st, const char* klassName, Symbol* exception_name, TRAPS) {
 126   if (HAS_PENDING_EXCEPTION) {
 127     st->print("Verification for %s has", klassName);
 128     st->print_cr(" exception pending %s ",
 129                  PENDING_EXCEPTION->klass()->external_name());
 130   } else if (exception_name != NULL) {
 131     st->print_cr("Verification for %s failed", klassName);
 132   }
 133   st->print_cr("End class verification for: %s", klassName);
 134 }
 135 
 136 bool Verifier::verify(InstanceKlass* klass, bool should_verify_class, TRAPS) {
 137   HandleMark hm(THREAD);
 138   ResourceMark rm(THREAD);
 139 
 140   // Eagerly allocate the identity hash code for a klass. This is a fallout
 141   // from 6320749 and 8059924: hash code generator is not supposed to be called
 142   // during the safepoint, but it allows to sneak the hashcode in during
 143   // verification. Without this eager hashcode generation, we may end up
 144   // installing the hashcode during some other operation, which may be at
 145   // safepoint -- blowing up the checks. It was previously done as the side
 146   // effect (sic!) for external_name(), but instead of doing that, we opt to
 147   // explicitly push the hashcode in here. This is signify the following block
 148   // is IMPORTANT:
 149   if (klass->java_mirror() != NULL) {
 150     klass->java_mirror()->identity_hash();
 151   }
 152 
 153   if (!is_eligible_for_verification(klass, should_verify_class)) {
 154     return true;
 155   }
 156 
 157   // Timer includes any side effects of class verification (resolution,
 158   // etc), but not recursive calls to Verifier::verify().
 159   JavaThread* jt = (JavaThread*)THREAD;
 160   PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
 161                            ClassLoader::perf_class_verify_selftime(),
 162                            ClassLoader::perf_classes_verified(),
 163                            jt->get_thread_stat()->perf_recursion_counts_addr(),
 164                            jt->get_thread_stat()->perf_timers_addr(),
 165                            PerfClassTraceTime::CLASS_VERIFY);
 166 
 167   // If the class should be verified, first see if we can use the split
 168   // verifier.  If not, or if verification fails and FailOverToOldVerifier
 169   // is set, then call the inference verifier.
 170   Symbol* exception_name = NULL;
 171   const size_t message_buffer_len = klass->name()->utf8_length() + 1024;
 172   char* message_buffer = NULL;
 173   char* exception_message = NULL;
 174 
 175   bool can_failover = FailOverToOldVerifier &&
 176      klass->major_version() < NOFAILOVER_MAJOR_VERSION;
 177 
 178   log_info(class, init)("Start class verification for: %s", klass->external_name());
 179   if (klass->major_version() >= STACKMAP_ATTRIBUTE_MAJOR_VERSION) {
 180     ClassVerifier split_verifier(klass, THREAD);
 181     split_verifier.verify_class(THREAD);
 182     exception_name = split_verifier.result();
 183     if (can_failover && !HAS_PENDING_EXCEPTION &&
 184         (exception_name == vmSymbols::java_lang_VerifyError() ||
 185          exception_name == vmSymbols::java_lang_ClassFormatError())) {
 186       log_info(verification)("Fail over class verification to old verifier for: %s", klass->external_name());
 187       log_info(class, init)("Fail over class verification to old verifier for: %s", klass->external_name());
 188       message_buffer = NEW_RESOURCE_ARRAY(char, message_buffer_len);
 189       exception_message = message_buffer;
 190       exception_name = inference_verify(
 191         klass, message_buffer, message_buffer_len, THREAD);
 192     }
 193     if (exception_name != NULL) {
 194       exception_message = split_verifier.exception_message();
 195     }
 196   } else {
 197     message_buffer = NEW_RESOURCE_ARRAY(char, message_buffer_len);
 198     exception_message = message_buffer;
 199     exception_name = inference_verify(
 200         klass, message_buffer, message_buffer_len, THREAD);
 201   }
 202 
 203   LogTarget(Info, class, init) lt1;
 204   if (lt1.is_enabled()) {
 205     LogStream ls(lt1);
 206     log_end_verification(&ls, klass->external_name(), exception_name, THREAD);
 207   }
 208   LogTarget(Info, verification) lt2;
 209   if (lt2.is_enabled()) {
 210     LogStream ls(lt2);
 211     log_end_verification(&ls, klass->external_name(), exception_name, THREAD);
 212   }
 213 
 214   if (HAS_PENDING_EXCEPTION) {
 215     return false; // use the existing exception
 216   } else if (exception_name == NULL) {
 217     return true; // verification succeeded
 218   } else { // VerifyError or ClassFormatError to be created and thrown
 219     Klass* kls =
 220       SystemDictionary::resolve_or_fail(exception_name, true, CHECK_false);
 221     if (log_is_enabled(Debug, class, resolve)) {
 222       Verifier::trace_class_resolution(kls, klass);
 223     }
 224 
 225     while (kls != NULL) {
 226       if (kls == klass) {
 227         // If the class being verified is the exception we're creating
 228         // or one of it's superclasses, we're in trouble and are going
 229         // to infinitely recurse when we try to initialize the exception.
 230         // So bail out here by throwing the preallocated VM error.
 231         THROW_OOP_(Universe::virtual_machine_error_instance(), false);
 232       }
 233       kls = kls->super();
 234     }
 235     if (message_buffer != NULL) {
 236       message_buffer[message_buffer_len - 1] = '\0'; // just to be sure
 237     }
 238     assert(exception_message != NULL, "");
 239     THROW_MSG_(exception_name, exception_message, false);
 240   }
 241 }
 242 
 243 bool Verifier::is_eligible_for_verification(InstanceKlass* klass, bool should_verify_class) {
 244   Symbol* name = klass->name();
 245   Klass* refl_magic_klass = SystemDictionary::reflect_MagicAccessorImpl_klass();
 246 
 247   bool is_reflect = refl_magic_klass != NULL && klass->is_subtype_of(refl_magic_klass);
 248 
 249   return (should_verify_for(klass->class_loader(), should_verify_class) &&
 250     // return if the class is a bootstrapping class
 251     // or defineClass specified not to verify by default (flags override passed arg)
 252     // We need to skip the following four for bootstraping
 253     name != vmSymbols::java_lang_Object() &&
 254     name != vmSymbols::java_lang_Class() &&
 255     name != vmSymbols::java_lang_String() &&
 256     name != vmSymbols::java_lang_Throwable() &&
 257 
 258     // Can not verify the bytecodes for shared classes because they have
 259     // already been rewritten to contain constant pool cache indices,
 260     // which the verifier can't understand.
 261     // Shared classes shouldn't have stackmaps either.
 262     !klass->is_shared() &&
 263 
 264     // As of the fix for 4486457 we disable verification for all of the
 265     // dynamically-generated bytecodes associated with the 1.4
 266     // reflection implementation, not just those associated with
 267     // jdk/internal/reflect/SerializationConstructorAccessor.
 268     // NOTE: this is called too early in the bootstrapping process to be
 269     // guarded by Universe::is_gte_jdk14x_version().
 270     // Also for lambda generated code, gte jdk8
 271     (!is_reflect));
 272 }
 273 
 274 Symbol* Verifier::inference_verify(
 275     InstanceKlass* klass, char* message, size_t message_len, TRAPS) {
 276   JavaThread* thread = (JavaThread*)THREAD;
 277   JNIEnv *env = thread->jni_environment();
 278 
 279   void* verify_func = verify_byte_codes_fn();
 280 
 281   if (verify_func == NULL) {
 282     jio_snprintf(message, message_len, "Could not link verifier");
 283     return vmSymbols::java_lang_VerifyError();
 284   }
 285 
 286   ResourceMark rm(THREAD);
 287   log_info(verification)("Verifying class %s with old format", klass->external_name());
 288 
 289   jclass cls = (jclass) JNIHandles::make_local(env, klass->java_mirror());
 290   jint result;
 291 
 292   {
 293     HandleMark hm(thread);
 294     ThreadToNativeFromVM ttn(thread);
 295     // ThreadToNativeFromVM takes care of changing thread_state, so safepoint
 296     // code knows that we have left the VM
 297 
 298     if (_is_new_verify_byte_codes_fn) {
 299       verify_byte_codes_fn_new_t func =
 300         CAST_TO_FN_PTR(verify_byte_codes_fn_new_t, verify_func);
 301       result = (*func)(env, cls, message, (int)message_len,
 302           klass->major_version());
 303     } else {
 304       verify_byte_codes_fn_t func =
 305         CAST_TO_FN_PTR(verify_byte_codes_fn_t, verify_func);
 306       result = (*func)(env, cls, message, (int)message_len);
 307     }
 308   }
 309 
 310   JNIHandles::destroy_local(cls);
 311 
 312   // These numbers are chosen so that VerifyClassCodes interface doesn't need
 313   // to be changed (still return jboolean (unsigned char)), and result is
 314   // 1 when verification is passed.
 315   if (result == 0) {
 316     return vmSymbols::java_lang_VerifyError();
 317   } else if (result == 1) {
 318     return NULL; // verified.
 319   } else if (result == 2) {
 320     THROW_MSG_(vmSymbols::java_lang_OutOfMemoryError(), message, NULL);
 321   } else if (result == 3) {
 322     return vmSymbols::java_lang_ClassFormatError();
 323   } else {
 324     ShouldNotReachHere();
 325     return NULL;
 326   }
 327 }
 328 
 329 TypeOrigin TypeOrigin::null() {
 330   return TypeOrigin();
 331 }
 332 TypeOrigin TypeOrigin::local(u2 index, StackMapFrame* frame) {
 333   assert(frame != NULL, "Must have a frame");
 334   return TypeOrigin(CF_LOCALS, index, StackMapFrame::copy(frame),
 335      frame->local_at(index));
 336 }
 337 TypeOrigin TypeOrigin::stack(u2 index, StackMapFrame* frame) {
 338   assert(frame != NULL, "Must have a frame");
 339   return TypeOrigin(CF_STACK, index, StackMapFrame::copy(frame),
 340       frame->stack_at(index));
 341 }
 342 TypeOrigin TypeOrigin::sm_local(u2 index, StackMapFrame* frame) {
 343   assert(frame != NULL, "Must have a frame");
 344   return TypeOrigin(SM_LOCALS, index, StackMapFrame::copy(frame),
 345       frame->local_at(index));
 346 }
 347 TypeOrigin TypeOrigin::sm_stack(u2 index, StackMapFrame* frame) {
 348   assert(frame != NULL, "Must have a frame");
 349   return TypeOrigin(SM_STACK, index, StackMapFrame::copy(frame),
 350       frame->stack_at(index));
 351 }
 352 TypeOrigin TypeOrigin::bad_index(u2 index) {
 353   return TypeOrigin(BAD_INDEX, index, NULL, VerificationType::bogus_type());
 354 }
 355 TypeOrigin TypeOrigin::cp(u2 index, VerificationType vt) {
 356   return TypeOrigin(CONST_POOL, index, NULL, vt);
 357 }
 358 TypeOrigin TypeOrigin::signature(VerificationType vt) {
 359   return TypeOrigin(SIG, 0, NULL, vt);
 360 }
 361 TypeOrigin TypeOrigin::implicit(VerificationType t) {
 362   return TypeOrigin(IMPLICIT, 0, NULL, t);
 363 }
 364 TypeOrigin TypeOrigin::frame(StackMapFrame* frame) {
 365   return TypeOrigin(FRAME_ONLY, 0, StackMapFrame::copy(frame),
 366                     VerificationType::bogus_type());
 367 }
 368 
 369 void TypeOrigin::reset_frame() {
 370   if (_frame != NULL) {
 371     _frame->restore();
 372   }
 373 }
 374 
 375 void TypeOrigin::details(outputStream* ss) const {
 376   _type.print_on(ss);
 377   switch (_origin) {
 378     case CF_LOCALS:
 379       ss->print(" (current frame, locals[%d])", _index);
 380       break;
 381     case CF_STACK:
 382       ss->print(" (current frame, stack[%d])", _index);
 383       break;
 384     case SM_LOCALS:
 385       ss->print(" (stack map, locals[%d])", _index);
 386       break;
 387     case SM_STACK:
 388       ss->print(" (stack map, stack[%d])", _index);
 389       break;
 390     case CONST_POOL:
 391       ss->print(" (constant pool %d)", _index);
 392       break;
 393     case SIG:
 394       ss->print(" (from method signature)");
 395       break;
 396     case IMPLICIT:
 397     case FRAME_ONLY:
 398     case NONE:
 399     default:
 400       ;
 401   }
 402 }
 403 
 404 #ifdef ASSERT
 405 void TypeOrigin::print_on(outputStream* str) const {
 406   str->print("{%d,%d,%p:", _origin, _index, _frame);
 407   if (_frame != NULL) {
 408     _frame->print_on(str);
 409   } else {
 410     str->print("null");
 411   }
 412   str->print(",");
 413   _type.print_on(str);
 414   str->print("}");
 415 }
 416 #endif
 417 
 418 void ErrorContext::details(outputStream* ss, const Method* method) const {
 419   if (is_valid()) {
 420     ss->cr();
 421     ss->print_cr("Exception Details:");
 422     location_details(ss, method);
 423     reason_details(ss);
 424     frame_details(ss);
 425     bytecode_details(ss, method);
 426     handler_details(ss, method);
 427     stackmap_details(ss, method);
 428   }
 429 }
 430 
 431 void ErrorContext::reason_details(outputStream* ss) const {
 432   streamIndentor si(ss);
 433   ss->indent().print_cr("Reason:");
 434   streamIndentor si2(ss);
 435   ss->indent().print("%s", "");
 436   switch (_fault) {
 437     case INVALID_BYTECODE:
 438       ss->print("Error exists in the bytecode");
 439       break;
 440     case WRONG_TYPE:
 441       if (_expected.is_valid()) {
 442         ss->print("Type ");
 443         _type.details(ss);
 444         ss->print(" is not assignable to ");
 445         _expected.details(ss);
 446       } else {
 447         ss->print("Invalid type: ");
 448         _type.details(ss);
 449       }
 450       break;
 451     case FLAGS_MISMATCH:
 452       if (_expected.is_valid()) {
 453         ss->print("Current frame's flags are not assignable "
 454                   "to stack map frame's.");
 455       } else {
 456         ss->print("Current frame's flags are invalid in this context.");
 457       }
 458       break;
 459     case BAD_CP_INDEX:
 460       ss->print("Constant pool index %d is invalid", _type.index());
 461       break;
 462     case BAD_LOCAL_INDEX:
 463       ss->print("Local index %d is invalid", _type.index());
 464       break;
 465     case LOCALS_SIZE_MISMATCH:
 466       ss->print("Current frame's local size doesn't match stackmap.");
 467       break;
 468     case STACK_SIZE_MISMATCH:
 469       ss->print("Current frame's stack size doesn't match stackmap.");
 470       break;
 471     case STACK_OVERFLOW:
 472       ss->print("Exceeded max stack size.");
 473       break;
 474     case STACK_UNDERFLOW:
 475       ss->print("Attempt to pop empty stack.");
 476       break;
 477     case MISSING_STACKMAP:
 478       ss->print("Expected stackmap frame at this location.");
 479       break;
 480     case BAD_STACKMAP:
 481       ss->print("Invalid stackmap specification.");
 482       break;
 483     case UNKNOWN:
 484     default:
 485       ShouldNotReachHere();
 486       ss->print_cr("Unknown");
 487   }
 488   ss->cr();
 489 }
 490 
 491 void ErrorContext::location_details(outputStream* ss, const Method* method) const {
 492   if (_bci != -1 && method != NULL) {
 493     streamIndentor si(ss);
 494     const char* bytecode_name = "<invalid>";
 495     if (method->validate_bci(_bci) != -1) {
 496       Bytecodes::Code code = Bytecodes::code_or_bp_at(method->bcp_from(_bci));
 497       if (Bytecodes::is_defined(code)) {
 498           bytecode_name = Bytecodes::name(code);
 499       } else {
 500           bytecode_name = "<illegal>";
 501       }
 502     }
 503     InstanceKlass* ik = method->method_holder();
 504     ss->indent().print_cr("Location:");
 505     streamIndentor si2(ss);
 506     ss->indent().print_cr("%s.%s%s @%d: %s",
 507         ik->name()->as_C_string(), method->name()->as_C_string(),
 508         method->signature()->as_C_string(), _bci, bytecode_name);
 509   }
 510 }
 511 
 512 void ErrorContext::frame_details(outputStream* ss) const {
 513   streamIndentor si(ss);
 514   if (_type.is_valid() && _type.frame() != NULL) {
 515     ss->indent().print_cr("Current Frame:");
 516     streamIndentor si2(ss);
 517     _type.frame()->print_on(ss);
 518   }
 519   if (_expected.is_valid() && _expected.frame() != NULL) {
 520     ss->indent().print_cr("Stackmap Frame:");
 521     streamIndentor si2(ss);
 522     _expected.frame()->print_on(ss);
 523   }
 524 }
 525 
 526 void ErrorContext::bytecode_details(outputStream* ss, const Method* method) const {
 527   if (method != NULL) {
 528     streamIndentor si(ss);
 529     ss->indent().print_cr("Bytecode:");
 530     streamIndentor si2(ss);
 531     ss->print_data(method->code_base(), method->code_size(), false);
 532   }
 533 }
 534 
 535 void ErrorContext::handler_details(outputStream* ss, const Method* method) const {
 536   if (method != NULL) {
 537     streamIndentor si(ss);
 538     ExceptionTable table(method);
 539     if (table.length() > 0) {
 540       ss->indent().print_cr("Exception Handler Table:");
 541       streamIndentor si2(ss);
 542       for (int i = 0; i < table.length(); ++i) {
 543         ss->indent().print_cr("bci [%d, %d] => handler: %d", table.start_pc(i),
 544             table.end_pc(i), table.handler_pc(i));
 545       }
 546     }
 547   }
 548 }
 549 
 550 void ErrorContext::stackmap_details(outputStream* ss, const Method* method) const {
 551   if (method != NULL && method->has_stackmap_table()) {
 552     streamIndentor si(ss);
 553     ss->indent().print_cr("Stackmap Table:");
 554     Array<u1>* data = method->stackmap_data();
 555     stack_map_table* sm_table =
 556         stack_map_table::at((address)data->adr_at(0));
 557     stack_map_frame* sm_frame = sm_table->entries();
 558     streamIndentor si2(ss);
 559     int current_offset = -1;
 560     address end_of_sm_table = (address)sm_table + method->stackmap_data()->length();
 561     for (u2 i = 0; i < sm_table->number_of_entries(); ++i) {
 562       ss->indent();
 563       if (!sm_frame->verify((address)sm_frame, end_of_sm_table)) {
 564         sm_frame->print_truncated(ss, current_offset);
 565         return;
 566       }
 567       sm_frame->print_on(ss, current_offset);
 568       ss->cr();
 569       current_offset += sm_frame->offset_delta();
 570       sm_frame = sm_frame->next();
 571     }
 572   }
 573 }
 574 
 575 // Methods in ClassVerifier
 576 
 577 ClassVerifier::ClassVerifier(
 578     InstanceKlass* klass, TRAPS)
 579     : _thread(THREAD), _previous_symbol(NULL), _symbols(NULL), _exception_type(NULL),
 580       _message(NULL), _method_signatures_table(NULL), _klass(klass) {
 581   _this_type = VerificationType::reference_type(klass->name());
 582 }
 583 
 584 ClassVerifier::~ClassVerifier() {
 585   // Decrement the reference count for any symbols created.
 586   if (_symbols != NULL) {
 587     for (int i = 0; i < _symbols->length(); i++) {
 588       Symbol* s = _symbols->at(i);
 589       s->decrement_refcount();
 590     }
 591   }
 592 }
 593 
 594 VerificationType ClassVerifier::object_type() const {
 595   return VerificationType::reference_type(vmSymbols::java_lang_Object());
 596 }
 597 
 598 TypeOrigin ClassVerifier::ref_ctx(const char* sig) {
 599   VerificationType vt = VerificationType::reference_type(
 600                          create_temporary_symbol(sig, (int)strlen(sig)));
 601   return TypeOrigin::implicit(vt);
 602 }
 603 
 604 void ClassVerifier::verify_class(TRAPS) {
 605   log_info(verification)("Verifying class %s with new format", _klass->external_name());
 606 
 607   // Either verifying both local and remote classes or just remote classes.
 608   assert(BytecodeVerificationRemote, "Should not be here");
 609 
 610   // Create hash table containing method signatures.
 611   method_signatures_table_type method_signatures_table;
 612   set_method_signatures_table(&method_signatures_table);
 613 
 614   Array<Method*>* methods = _klass->methods();
 615   int num_methods = methods->length();
 616 
 617   for (int index = 0; index < num_methods; index++) {
 618     // Check for recursive re-verification before each method.
 619     if (was_recursively_verified())  return;
 620 
 621     Method* m = methods->at(index);
 622     if (m->is_native() || m->is_abstract() || m->is_overpass()) {
 623       // If m is native or abstract, skip it.  It is checked in class file
 624       // parser that methods do not override a final method.  Overpass methods
 625       // are trusted since the VM generates them.
 626       continue;
 627     }
 628     verify_method(methodHandle(THREAD, m), CHECK_VERIFY(this));
 629   }
 630 
 631   if (was_recursively_verified()){
 632     log_info(verification)("Recursive verification detected for: %s", _klass->external_name());
 633     log_info(class, init)("Recursive verification detected for: %s",
 634                         _klass->external_name());
 635   }
 636 }
 637 
 638 // Translate the signature entries into verification types and save them in
 639 // the growable array.  Also, save the count of arguments.
 640 void ClassVerifier::translate_signature(Symbol* const method_sig,
 641                                         sig_as_verification_types* sig_verif_types,
 642                                         TRAPS) {
 643   SignatureStream sig_stream(method_sig);
 644   VerificationType sig_type[2];
 645   int sig_i = 0;
 646   GrowableArray<VerificationType>* verif_types = sig_verif_types->sig_verif_types();
 647 
 648   // Translate the signature arguments into verification types.
 649   while (!sig_stream.at_return_type()) {
 650     int n = change_sig_to_verificationType(&sig_stream, sig_type);
 651     assert(n <= 2, "Unexpected signature type");
 652 
 653     // Store verification type(s).  Longs and Doubles each have two verificationTypes.
 654     for (int x = 0; x < n; x++) {
 655       verif_types->push(sig_type[x]);
 656     }
 657     sig_i += n;
 658     sig_stream.next();
 659   }
 660 
 661   // Set final arg count, not including the return type.  The final arg count will
 662   // be compared with sig_verify_types' length to see if there is a return type.
 663   sig_verif_types->set_num_args(sig_i);
 664 
 665   // Store verification type(s) for the return type, if there is one.
 666   if (sig_stream.type() != T_VOID) {
 667     int n = change_sig_to_verificationType(&sig_stream, sig_type);
 668     assert(n <= 2, "Unexpected signature return type");
 669     for (int y = 0; y < n; y++) {
 670       verif_types->push(sig_type[y]);
 671     }
 672   }
 673 }
 674 
 675 void ClassVerifier::create_method_sig_entry(sig_as_verification_types* sig_verif_types,
 676                                             int sig_index, TRAPS) {
 677   // Translate the signature into verification types.
 678   ConstantPool* cp = _klass->constants();
 679   Symbol* const method_sig = cp->symbol_at(sig_index);
 680   translate_signature(method_sig, sig_verif_types, CHECK_VERIFY(this));
 681 
 682   // Add the list of this signature's verification types to the table.
 683   bool is_unique = method_signatures_table()->put(sig_index, sig_verif_types);
 684   assert(is_unique, "Duplicate entries in method_signature_table");
 685 }
 686 
 687 void ClassVerifier::verify_method(const methodHandle& m, TRAPS) {
 688   HandleMark hm(THREAD);
 689   _method = m;   // initialize _method
 690   log_info(verification)("Verifying method %s", m->name_and_sig_as_C_string());
 691 
 692 // For clang, the only good constant format string is a literal constant format string.
 693 #define bad_type_msg "Bad type on operand stack in %s"
 694 
 695   int32_t max_stack = m->verifier_max_stack();
 696   int32_t max_locals = m->max_locals();
 697   constantPoolHandle cp(THREAD, m->constants());
 698 
 699   // Method signature was checked in ClassFileParser.
 700   assert(SignatureVerifier::is_valid_method_signature(m->signature()),
 701          "Invalid method signature");
 702 
 703   // Initial stack map frame: offset is 0, stack is initially empty.
 704   StackMapFrame current_frame(max_locals, max_stack, this);
 705   // Set initial locals
 706   VerificationType return_type = current_frame.set_locals_from_arg(
 707     m, current_type(), CHECK_VERIFY(this));
 708 
 709   int32_t stackmap_index = 0; // index to the stackmap array
 710 
 711   u4 code_length = m->code_size();
 712 
 713   // Scan the bytecode and map each instruction's start offset to a number.
 714   char* code_data = generate_code_data(m, code_length, CHECK_VERIFY(this));
 715 
 716   int ex_min = code_length;
 717   int ex_max = -1;
 718   // Look through each item on the exception table. Each of the fields must refer
 719   // to a legal instruction.
 720   if (was_recursively_verified()) return;
 721   verify_exception_handler_table(
 722     code_length, code_data, ex_min, ex_max, CHECK_VERIFY(this));
 723 
 724   // Look through each entry on the local variable table and make sure
 725   // its range of code array offsets is valid. (4169817)
 726   if (m->has_localvariable_table()) {
 727     verify_local_variable_table(code_length, code_data, CHECK_VERIFY(this));
 728   }
 729 
 730   Array<u1>* stackmap_data = m->stackmap_data();
 731   StackMapStream stream(stackmap_data);
 732   StackMapReader reader(this, &stream, code_data, code_length, THREAD);
 733   StackMapTable stackmap_table(&reader, &current_frame, max_locals, max_stack,
 734                                code_data, code_length, CHECK_VERIFY(this));
 735 
 736   LogTarget(Info, verification) lt;
 737   if (lt.is_enabled()) {
 738     ResourceMark rm(THREAD);
 739     LogStream ls(lt);
 740     stackmap_table.print_on(&ls);
 741   }
 742 
 743   RawBytecodeStream bcs(m);
 744 
 745   // Scan the byte code linearly from the start to the end
 746   bool no_control_flow = false; // Set to true when there is no direct control
 747                                 // flow from current instruction to the next
 748                                 // instruction in sequence
 749 
 750   Bytecodes::Code opcode;
 751   while (!bcs.is_last_bytecode()) {
 752     // Check for recursive re-verification before each bytecode.
 753     if (was_recursively_verified())  return;
 754 
 755     opcode = bcs.raw_next();
 756     u2 bci = bcs.bci();
 757 
 758     // Set current frame's offset to bci
 759     current_frame.set_offset(bci);
 760     current_frame.set_mark();
 761 
 762     // Make sure every offset in stackmap table point to the beginning to
 763     // an instruction. Match current_frame to stackmap_table entry with
 764     // the same offset if exists.
 765     stackmap_index = verify_stackmap_table(
 766       stackmap_index, bci, &current_frame, &stackmap_table,
 767       no_control_flow, CHECK_VERIFY(this));
 768 
 769 
 770     bool this_uninit = false;  // Set to true when invokespecial <init> initialized 'this'
 771     bool verified_exc_handlers = false;
 772 
 773     // Merge with the next instruction
 774     {
 775       u2 index;
 776       int target;
 777       VerificationType type, type2;
 778       VerificationType atype;
 779 
 780       LogTarget(Info, verification) lt;
 781       if (lt.is_enabled()) {
 782         ResourceMark rm(THREAD);
 783         LogStream ls(lt);
 784         current_frame.print_on(&ls);
 785         lt.print("offset = %d,  opcode = %s", bci,
 786                  opcode == Bytecodes::_illegal ? "illegal" : Bytecodes::name(opcode));
 787       }
 788 
 789       // Make sure wide instruction is in correct format
 790       if (bcs.is_wide()) {
 791         if (opcode != Bytecodes::_iinc   && opcode != Bytecodes::_iload  &&
 792             opcode != Bytecodes::_aload  && opcode != Bytecodes::_lload  &&
 793             opcode != Bytecodes::_istore && opcode != Bytecodes::_astore &&
 794             opcode != Bytecodes::_lstore && opcode != Bytecodes::_fload  &&
 795             opcode != Bytecodes::_dload  && opcode != Bytecodes::_fstore &&
 796             opcode != Bytecodes::_dstore) {
 797           /* Unreachable?  RawBytecodeStream's raw_next() returns 'illegal'
 798            * if we encounter a wide instruction that modifies an invalid
 799            * opcode (not one of the ones listed above) */
 800           verify_error(ErrorContext::bad_code(bci), "Bad wide instruction");
 801           return;
 802         }
 803       }
 804 
 805       // Look for possible jump target in exception handlers and see if it
 806       // matches current_frame.  Do this check here for astore*, dstore*,
 807       // fstore*, istore*, and lstore* opcodes because they can change the type
 808       // state by adding a local.  JVM Spec says that the incoming type state
 809       // should be used for this check.  So, do the check here before a possible
 810       // local is added to the type state.
 811       if (Bytecodes::is_store_into_local(opcode) && bci >= ex_min && bci < ex_max) {
 812         if (was_recursively_verified()) return;
 813         verify_exception_handler_targets(
 814           bci, this_uninit, &current_frame, &stackmap_table, CHECK_VERIFY(this));
 815         verified_exc_handlers = true;
 816       }
 817 
 818       if (was_recursively_verified()) return;
 819 
 820       switch (opcode) {
 821         case Bytecodes::_nop :
 822           no_control_flow = false; break;
 823         case Bytecodes::_aconst_null :
 824           current_frame.push_stack(
 825             VerificationType::null_type(), CHECK_VERIFY(this));
 826           no_control_flow = false; break;
 827         case Bytecodes::_iconst_m1 :
 828         case Bytecodes::_iconst_0 :
 829         case Bytecodes::_iconst_1 :
 830         case Bytecodes::_iconst_2 :
 831         case Bytecodes::_iconst_3 :
 832         case Bytecodes::_iconst_4 :
 833         case Bytecodes::_iconst_5 :
 834           current_frame.push_stack(
 835             VerificationType::integer_type(), CHECK_VERIFY(this));
 836           no_control_flow = false; break;
 837         case Bytecodes::_lconst_0 :
 838         case Bytecodes::_lconst_1 :
 839           current_frame.push_stack_2(
 840             VerificationType::long_type(),
 841             VerificationType::long2_type(), CHECK_VERIFY(this));
 842           no_control_flow = false; break;
 843         case Bytecodes::_fconst_0 :
 844         case Bytecodes::_fconst_1 :
 845         case Bytecodes::_fconst_2 :
 846           current_frame.push_stack(
 847             VerificationType::float_type(), CHECK_VERIFY(this));
 848           no_control_flow = false; break;
 849         case Bytecodes::_dconst_0 :
 850         case Bytecodes::_dconst_1 :
 851           current_frame.push_stack_2(
 852             VerificationType::double_type(),
 853             VerificationType::double2_type(), CHECK_VERIFY(this));
 854           no_control_flow = false; break;
 855         case Bytecodes::_sipush :
 856         case Bytecodes::_bipush :
 857           current_frame.push_stack(
 858             VerificationType::integer_type(), CHECK_VERIFY(this));
 859           no_control_flow = false; break;
 860         case Bytecodes::_ldc :
 861           verify_ldc(
 862             opcode, bcs.get_index_u1(), &current_frame,
 863             cp, bci, CHECK_VERIFY(this));
 864           no_control_flow = false; break;
 865         case Bytecodes::_ldc_w :
 866         case Bytecodes::_ldc2_w :
 867           verify_ldc(
 868             opcode, bcs.get_index_u2(), &current_frame,
 869             cp, bci, CHECK_VERIFY(this));
 870           no_control_flow = false; break;
 871         case Bytecodes::_iload :
 872           verify_iload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
 873           no_control_flow = false; break;
 874         case Bytecodes::_iload_0 :
 875         case Bytecodes::_iload_1 :
 876         case Bytecodes::_iload_2 :
 877         case Bytecodes::_iload_3 :
 878           index = opcode - Bytecodes::_iload_0;
 879           verify_iload(index, &current_frame, CHECK_VERIFY(this));
 880           no_control_flow = false; break;
 881         case Bytecodes::_lload :
 882           verify_lload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
 883           no_control_flow = false; break;
 884         case Bytecodes::_lload_0 :
 885         case Bytecodes::_lload_1 :
 886         case Bytecodes::_lload_2 :
 887         case Bytecodes::_lload_3 :
 888           index = opcode - Bytecodes::_lload_0;
 889           verify_lload(index, &current_frame, CHECK_VERIFY(this));
 890           no_control_flow = false; break;
 891         case Bytecodes::_fload :
 892           verify_fload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
 893           no_control_flow = false; break;
 894         case Bytecodes::_fload_0 :
 895         case Bytecodes::_fload_1 :
 896         case Bytecodes::_fload_2 :
 897         case Bytecodes::_fload_3 :
 898           index = opcode - Bytecodes::_fload_0;
 899           verify_fload(index, &current_frame, CHECK_VERIFY(this));
 900           no_control_flow = false; break;
 901         case Bytecodes::_dload :
 902           verify_dload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
 903           no_control_flow = false; break;
 904         case Bytecodes::_dload_0 :
 905         case Bytecodes::_dload_1 :
 906         case Bytecodes::_dload_2 :
 907         case Bytecodes::_dload_3 :
 908           index = opcode - Bytecodes::_dload_0;
 909           verify_dload(index, &current_frame, CHECK_VERIFY(this));
 910           no_control_flow = false; break;
 911         case Bytecodes::_aload :
 912           verify_aload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
 913           no_control_flow = false; break;
 914         case Bytecodes::_aload_0 :
 915         case Bytecodes::_aload_1 :
 916         case Bytecodes::_aload_2 :
 917         case Bytecodes::_aload_3 :
 918           index = opcode - Bytecodes::_aload_0;
 919           verify_aload(index, &current_frame, CHECK_VERIFY(this));
 920           no_control_flow = false; break;
 921         case Bytecodes::_iaload :
 922           type = current_frame.pop_stack(
 923             VerificationType::integer_type(), CHECK_VERIFY(this));
 924           atype = current_frame.pop_stack(
 925             VerificationType::reference_check(), CHECK_VERIFY(this));
 926           if (!atype.is_int_array()) {
 927             verify_error(ErrorContext::bad_type(bci,
 928                 current_frame.stack_top_ctx(), ref_ctx("[I")),
 929                 bad_type_msg, "iaload");
 930             return;
 931           }
 932           current_frame.push_stack(
 933             VerificationType::integer_type(), CHECK_VERIFY(this));
 934           no_control_flow = false; break;
 935         case Bytecodes::_baload :
 936           type = current_frame.pop_stack(
 937             VerificationType::integer_type(), CHECK_VERIFY(this));
 938           atype = current_frame.pop_stack(
 939             VerificationType::reference_check(), CHECK_VERIFY(this));
 940           if (!atype.is_bool_array() && !atype.is_byte_array()) {
 941             verify_error(
 942                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
 943                 bad_type_msg, "baload");
 944             return;
 945           }
 946           current_frame.push_stack(
 947             VerificationType::integer_type(), CHECK_VERIFY(this));
 948           no_control_flow = false; break;
 949         case Bytecodes::_caload :
 950           type = current_frame.pop_stack(
 951             VerificationType::integer_type(), CHECK_VERIFY(this));
 952           atype = current_frame.pop_stack(
 953             VerificationType::reference_check(), CHECK_VERIFY(this));
 954           if (!atype.is_char_array()) {
 955             verify_error(ErrorContext::bad_type(bci,
 956                 current_frame.stack_top_ctx(), ref_ctx("[C")),
 957                 bad_type_msg, "caload");
 958             return;
 959           }
 960           current_frame.push_stack(
 961             VerificationType::integer_type(), CHECK_VERIFY(this));
 962           no_control_flow = false; break;
 963         case Bytecodes::_saload :
 964           type = current_frame.pop_stack(
 965             VerificationType::integer_type(), CHECK_VERIFY(this));
 966           atype = current_frame.pop_stack(
 967             VerificationType::reference_check(), CHECK_VERIFY(this));
 968           if (!atype.is_short_array()) {
 969             verify_error(ErrorContext::bad_type(bci,
 970                 current_frame.stack_top_ctx(), ref_ctx("[S")),
 971                 bad_type_msg, "saload");
 972             return;
 973           }
 974           current_frame.push_stack(
 975             VerificationType::integer_type(), CHECK_VERIFY(this));
 976           no_control_flow = false; break;
 977         case Bytecodes::_laload :
 978           type = current_frame.pop_stack(
 979             VerificationType::integer_type(), CHECK_VERIFY(this));
 980           atype = current_frame.pop_stack(
 981             VerificationType::reference_check(), CHECK_VERIFY(this));
 982           if (!atype.is_long_array()) {
 983             verify_error(ErrorContext::bad_type(bci,
 984                 current_frame.stack_top_ctx(), ref_ctx("[J")),
 985                 bad_type_msg, "laload");
 986             return;
 987           }
 988           current_frame.push_stack_2(
 989             VerificationType::long_type(),
 990             VerificationType::long2_type(), CHECK_VERIFY(this));
 991           no_control_flow = false; break;
 992         case Bytecodes::_faload :
 993           type = current_frame.pop_stack(
 994             VerificationType::integer_type(), CHECK_VERIFY(this));
 995           atype = current_frame.pop_stack(
 996             VerificationType::reference_check(), CHECK_VERIFY(this));
 997           if (!atype.is_float_array()) {
 998             verify_error(ErrorContext::bad_type(bci,
 999                 current_frame.stack_top_ctx(), ref_ctx("[F")),
1000                 bad_type_msg, "faload");
1001             return;
1002           }
1003           current_frame.push_stack(
1004             VerificationType::float_type(), CHECK_VERIFY(this));
1005           no_control_flow = false; break;
1006         case Bytecodes::_daload :
1007           type = current_frame.pop_stack(
1008             VerificationType::integer_type(), CHECK_VERIFY(this));
1009           atype = current_frame.pop_stack(
1010             VerificationType::reference_check(), CHECK_VERIFY(this));
1011           if (!atype.is_double_array()) {
1012             verify_error(ErrorContext::bad_type(bci,
1013                 current_frame.stack_top_ctx(), ref_ctx("[D")),
1014                 bad_type_msg, "daload");
1015             return;
1016           }
1017           current_frame.push_stack_2(
1018             VerificationType::double_type(),
1019             VerificationType::double2_type(), CHECK_VERIFY(this));
1020           no_control_flow = false; break;
1021         case Bytecodes::_aaload : {
1022           type = current_frame.pop_stack(
1023             VerificationType::integer_type(), CHECK_VERIFY(this));
1024           atype = current_frame.pop_stack(
1025             VerificationType::reference_check(), CHECK_VERIFY(this));
1026           if (!atype.is_reference_array()) {
1027             verify_error(ErrorContext::bad_type(bci,
1028                 current_frame.stack_top_ctx(),
1029                 TypeOrigin::implicit(VerificationType::reference_check())),
1030                 bad_type_msg, "aaload");
1031             return;
1032           }
1033           if (atype.is_null()) {
1034             current_frame.push_stack(
1035               VerificationType::null_type(), CHECK_VERIFY(this));
1036           } else {
1037             VerificationType component =
1038               atype.get_component(this, CHECK_VERIFY(this));
1039             current_frame.push_stack(component, CHECK_VERIFY(this));
1040           }
1041           no_control_flow = false; break;
1042         }
1043         case Bytecodes::_istore :
1044           verify_istore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
1045           no_control_flow = false; break;
1046         case Bytecodes::_istore_0 :
1047         case Bytecodes::_istore_1 :
1048         case Bytecodes::_istore_2 :
1049         case Bytecodes::_istore_3 :
1050           index = opcode - Bytecodes::_istore_0;
1051           verify_istore(index, &current_frame, CHECK_VERIFY(this));
1052           no_control_flow = false; break;
1053         case Bytecodes::_lstore :
1054           verify_lstore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
1055           no_control_flow = false; break;
1056         case Bytecodes::_lstore_0 :
1057         case Bytecodes::_lstore_1 :
1058         case Bytecodes::_lstore_2 :
1059         case Bytecodes::_lstore_3 :
1060           index = opcode - Bytecodes::_lstore_0;
1061           verify_lstore(index, &current_frame, CHECK_VERIFY(this));
1062           no_control_flow = false; break;
1063         case Bytecodes::_fstore :
1064           verify_fstore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
1065           no_control_flow = false; break;
1066         case Bytecodes::_fstore_0 :
1067         case Bytecodes::_fstore_1 :
1068         case Bytecodes::_fstore_2 :
1069         case Bytecodes::_fstore_3 :
1070           index = opcode - Bytecodes::_fstore_0;
1071           verify_fstore(index, &current_frame, CHECK_VERIFY(this));
1072           no_control_flow = false; break;
1073         case Bytecodes::_dstore :
1074           verify_dstore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
1075           no_control_flow = false; break;
1076         case Bytecodes::_dstore_0 :
1077         case Bytecodes::_dstore_1 :
1078         case Bytecodes::_dstore_2 :
1079         case Bytecodes::_dstore_3 :
1080           index = opcode - Bytecodes::_dstore_0;
1081           verify_dstore(index, &current_frame, CHECK_VERIFY(this));
1082           no_control_flow = false; break;
1083         case Bytecodes::_astore :
1084           verify_astore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
1085           no_control_flow = false; break;
1086         case Bytecodes::_astore_0 :
1087         case Bytecodes::_astore_1 :
1088         case Bytecodes::_astore_2 :
1089         case Bytecodes::_astore_3 :
1090           index = opcode - Bytecodes::_astore_0;
1091           verify_astore(index, &current_frame, CHECK_VERIFY(this));
1092           no_control_flow = false; break;
1093         case Bytecodes::_iastore :
1094           type = current_frame.pop_stack(
1095             VerificationType::integer_type(), CHECK_VERIFY(this));
1096           type2 = current_frame.pop_stack(
1097             VerificationType::integer_type(), CHECK_VERIFY(this));
1098           atype = current_frame.pop_stack(
1099             VerificationType::reference_check(), CHECK_VERIFY(this));
1100           if (!atype.is_int_array()) {
1101             verify_error(ErrorContext::bad_type(bci,
1102                 current_frame.stack_top_ctx(), ref_ctx("[I")),
1103                 bad_type_msg, "iastore");
1104             return;
1105           }
1106           no_control_flow = false; break;
1107         case Bytecodes::_bastore :
1108           type = current_frame.pop_stack(
1109             VerificationType::integer_type(), CHECK_VERIFY(this));
1110           type2 = current_frame.pop_stack(
1111             VerificationType::integer_type(), CHECK_VERIFY(this));
1112           atype = current_frame.pop_stack(
1113             VerificationType::reference_check(), CHECK_VERIFY(this));
1114           if (!atype.is_bool_array() && !atype.is_byte_array()) {
1115             verify_error(
1116                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
1117                 bad_type_msg, "bastore");
1118             return;
1119           }
1120           no_control_flow = false; break;
1121         case Bytecodes::_castore :
1122           current_frame.pop_stack(
1123             VerificationType::integer_type(), CHECK_VERIFY(this));
1124           current_frame.pop_stack(
1125             VerificationType::integer_type(), CHECK_VERIFY(this));
1126           atype = current_frame.pop_stack(
1127             VerificationType::reference_check(), CHECK_VERIFY(this));
1128           if (!atype.is_char_array()) {
1129             verify_error(ErrorContext::bad_type(bci,
1130                 current_frame.stack_top_ctx(), ref_ctx("[C")),
1131                 bad_type_msg, "castore");
1132             return;
1133           }
1134           no_control_flow = false; break;
1135         case Bytecodes::_sastore :
1136           current_frame.pop_stack(
1137             VerificationType::integer_type(), CHECK_VERIFY(this));
1138           current_frame.pop_stack(
1139             VerificationType::integer_type(), CHECK_VERIFY(this));
1140           atype = current_frame.pop_stack(
1141             VerificationType::reference_check(), CHECK_VERIFY(this));
1142           if (!atype.is_short_array()) {
1143             verify_error(ErrorContext::bad_type(bci,
1144                 current_frame.stack_top_ctx(), ref_ctx("[S")),
1145                 bad_type_msg, "sastore");
1146             return;
1147           }
1148           no_control_flow = false; break;
1149         case Bytecodes::_lastore :
1150           current_frame.pop_stack_2(
1151             VerificationType::long2_type(),
1152             VerificationType::long_type(), CHECK_VERIFY(this));
1153           current_frame.pop_stack(
1154             VerificationType::integer_type(), CHECK_VERIFY(this));
1155           atype = current_frame.pop_stack(
1156             VerificationType::reference_check(), CHECK_VERIFY(this));
1157           if (!atype.is_long_array()) {
1158             verify_error(ErrorContext::bad_type(bci,
1159                 current_frame.stack_top_ctx(), ref_ctx("[J")),
1160                 bad_type_msg, "lastore");
1161             return;
1162           }
1163           no_control_flow = false; break;
1164         case Bytecodes::_fastore :
1165           current_frame.pop_stack(
1166             VerificationType::float_type(), CHECK_VERIFY(this));
1167           current_frame.pop_stack
1168             (VerificationType::integer_type(), CHECK_VERIFY(this));
1169           atype = current_frame.pop_stack(
1170             VerificationType::reference_check(), CHECK_VERIFY(this));
1171           if (!atype.is_float_array()) {
1172             verify_error(ErrorContext::bad_type(bci,
1173                 current_frame.stack_top_ctx(), ref_ctx("[F")),
1174                 bad_type_msg, "fastore");
1175             return;
1176           }
1177           no_control_flow = false; break;
1178         case Bytecodes::_dastore :
1179           current_frame.pop_stack_2(
1180             VerificationType::double2_type(),
1181             VerificationType::double_type(), CHECK_VERIFY(this));
1182           current_frame.pop_stack(
1183             VerificationType::integer_type(), CHECK_VERIFY(this));
1184           atype = current_frame.pop_stack(
1185             VerificationType::reference_check(), CHECK_VERIFY(this));
1186           if (!atype.is_double_array()) {
1187             verify_error(ErrorContext::bad_type(bci,
1188                 current_frame.stack_top_ctx(), ref_ctx("[D")),
1189                 bad_type_msg, "dastore");
1190             return;
1191           }
1192           no_control_flow = false; break;
1193         case Bytecodes::_aastore :
1194           type = current_frame.pop_stack(object_type(), CHECK_VERIFY(this));
1195           type2 = current_frame.pop_stack(
1196             VerificationType::integer_type(), CHECK_VERIFY(this));
1197           atype = current_frame.pop_stack(
1198             VerificationType::reference_check(), CHECK_VERIFY(this));
1199           // more type-checking is done at runtime
1200           if (!atype.is_reference_array()) {
1201             verify_error(ErrorContext::bad_type(bci,
1202                 current_frame.stack_top_ctx(),
1203                 TypeOrigin::implicit(VerificationType::reference_check())),
1204                 bad_type_msg, "aastore");
1205             return;
1206           }
1207           // 4938384: relaxed constraint in JVMS 3nd edition.
1208           no_control_flow = false; break;
1209         case Bytecodes::_pop :
1210           current_frame.pop_stack(
1211             VerificationType::category1_check(), CHECK_VERIFY(this));
1212           no_control_flow = false; break;
1213         case Bytecodes::_pop2 :
1214           type = current_frame.pop_stack(CHECK_VERIFY(this));
1215           if (type.is_category1()) {
1216             current_frame.pop_stack(
1217               VerificationType::category1_check(), CHECK_VERIFY(this));
1218           } else if (type.is_category2_2nd()) {
1219             current_frame.pop_stack(
1220               VerificationType::category2_check(), CHECK_VERIFY(this));
1221           } else {
1222             /* Unreachable? Would need a category2_1st on TOS
1223              * which does not appear possible. */
1224             verify_error(
1225                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
1226                 bad_type_msg, "pop2");
1227             return;
1228           }
1229           no_control_flow = false; break;
1230         case Bytecodes::_dup :
1231           type = current_frame.pop_stack(
1232             VerificationType::category1_check(), CHECK_VERIFY(this));
1233           current_frame.push_stack(type, CHECK_VERIFY(this));
1234           current_frame.push_stack(type, CHECK_VERIFY(this));
1235           no_control_flow = false; break;
1236         case Bytecodes::_dup_x1 :
1237           type = current_frame.pop_stack(
1238             VerificationType::category1_check(), CHECK_VERIFY(this));
1239           type2 = current_frame.pop_stack(
1240             VerificationType::category1_check(), CHECK_VERIFY(this));
1241           current_frame.push_stack(type, CHECK_VERIFY(this));
1242           current_frame.push_stack(type2, CHECK_VERIFY(this));
1243           current_frame.push_stack(type, CHECK_VERIFY(this));
1244           no_control_flow = false; break;
1245         case Bytecodes::_dup_x2 :
1246         {
1247           VerificationType type3;
1248           type = current_frame.pop_stack(
1249             VerificationType::category1_check(), CHECK_VERIFY(this));
1250           type2 = current_frame.pop_stack(CHECK_VERIFY(this));
1251           if (type2.is_category1()) {
1252             type3 = current_frame.pop_stack(
1253               VerificationType::category1_check(), CHECK_VERIFY(this));
1254           } else if (type2.is_category2_2nd()) {
1255             type3 = current_frame.pop_stack(
1256               VerificationType::category2_check(), CHECK_VERIFY(this));
1257           } else {
1258             /* Unreachable? Would need a category2_1st at stack depth 2 with
1259              * a category1 on TOS which does not appear possible. */
1260             verify_error(ErrorContext::bad_type(
1261                 bci, current_frame.stack_top_ctx()), bad_type_msg, "dup_x2");
1262             return;
1263           }
1264           current_frame.push_stack(type, CHECK_VERIFY(this));
1265           current_frame.push_stack(type3, CHECK_VERIFY(this));
1266           current_frame.push_stack(type2, CHECK_VERIFY(this));
1267           current_frame.push_stack(type, CHECK_VERIFY(this));
1268           no_control_flow = false; break;
1269         }
1270         case Bytecodes::_dup2 :
1271           type = current_frame.pop_stack(CHECK_VERIFY(this));
1272           if (type.is_category1()) {
1273             type2 = current_frame.pop_stack(
1274               VerificationType::category1_check(), CHECK_VERIFY(this));
1275           } else if (type.is_category2_2nd()) {
1276             type2 = current_frame.pop_stack(
1277               VerificationType::category2_check(), CHECK_VERIFY(this));
1278           } else {
1279             /* Unreachable?  Would need a category2_1st on TOS which does not
1280              * appear possible. */
1281             verify_error(
1282                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
1283                 bad_type_msg, "dup2");
1284             return;
1285           }
1286           current_frame.push_stack(type2, CHECK_VERIFY(this));
1287           current_frame.push_stack(type, CHECK_VERIFY(this));
1288           current_frame.push_stack(type2, CHECK_VERIFY(this));
1289           current_frame.push_stack(type, CHECK_VERIFY(this));
1290           no_control_flow = false; break;
1291         case Bytecodes::_dup2_x1 :
1292         {
1293           VerificationType type3;
1294           type = current_frame.pop_stack(CHECK_VERIFY(this));
1295           if (type.is_category1()) {
1296             type2 = current_frame.pop_stack(
1297               VerificationType::category1_check(), CHECK_VERIFY(this));
1298           } else if (type.is_category2_2nd()) {
1299             type2 = current_frame.pop_stack(
1300               VerificationType::category2_check(), CHECK_VERIFY(this));
1301           } else {
1302             /* Unreachable?  Would need a category2_1st on TOS which does
1303              * not appear possible. */
1304             verify_error(
1305                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
1306                 bad_type_msg, "dup2_x1");
1307             return;
1308           }
1309           type3 = current_frame.pop_stack(
1310             VerificationType::category1_check(), CHECK_VERIFY(this));
1311           current_frame.push_stack(type2, CHECK_VERIFY(this));
1312           current_frame.push_stack(type, CHECK_VERIFY(this));
1313           current_frame.push_stack(type3, CHECK_VERIFY(this));
1314           current_frame.push_stack(type2, CHECK_VERIFY(this));
1315           current_frame.push_stack(type, CHECK_VERIFY(this));
1316           no_control_flow = false; break;
1317         }
1318         case Bytecodes::_dup2_x2 :
1319         {
1320           VerificationType type3, type4;
1321           type = current_frame.pop_stack(CHECK_VERIFY(this));
1322           if (type.is_category1()) {
1323             type2 = current_frame.pop_stack(
1324               VerificationType::category1_check(), CHECK_VERIFY(this));
1325           } else if (type.is_category2_2nd()) {
1326             type2 = current_frame.pop_stack(
1327               VerificationType::category2_check(), CHECK_VERIFY(this));
1328           } else {
1329             /* Unreachable?  Would need a category2_1st on TOS which does
1330              * not appear possible. */
1331             verify_error(
1332                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
1333                 bad_type_msg, "dup2_x2");
1334             return;
1335           }
1336           type3 = current_frame.pop_stack(CHECK_VERIFY(this));
1337           if (type3.is_category1()) {
1338             type4 = current_frame.pop_stack(
1339               VerificationType::category1_check(), CHECK_VERIFY(this));
1340           } else if (type3.is_category2_2nd()) {
1341             type4 = current_frame.pop_stack(
1342               VerificationType::category2_check(), CHECK_VERIFY(this));
1343           } else {
1344             /* Unreachable?  Would need a category2_1st on TOS after popping
1345              * a long/double or two category 1's, which does not
1346              * appear possible. */
1347             verify_error(
1348                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),
1349                 bad_type_msg, "dup2_x2");
1350             return;
1351           }
1352           current_frame.push_stack(type2, CHECK_VERIFY(this));
1353           current_frame.push_stack(type, CHECK_VERIFY(this));
1354           current_frame.push_stack(type4, CHECK_VERIFY(this));
1355           current_frame.push_stack(type3, CHECK_VERIFY(this));
1356           current_frame.push_stack(type2, CHECK_VERIFY(this));
1357           current_frame.push_stack(type, CHECK_VERIFY(this));
1358           no_control_flow = false; break;
1359         }
1360         case Bytecodes::_swap :
1361           type = current_frame.pop_stack(
1362             VerificationType::category1_check(), CHECK_VERIFY(this));
1363           type2 = current_frame.pop_stack(
1364             VerificationType::category1_check(), CHECK_VERIFY(this));
1365           current_frame.push_stack(type, CHECK_VERIFY(this));
1366           current_frame.push_stack(type2, CHECK_VERIFY(this));
1367           no_control_flow = false; break;
1368         case Bytecodes::_iadd :
1369         case Bytecodes::_isub :
1370         case Bytecodes::_imul :
1371         case Bytecodes::_idiv :
1372         case Bytecodes::_irem :
1373         case Bytecodes::_ishl :
1374         case Bytecodes::_ishr :
1375         case Bytecodes::_iushr :
1376         case Bytecodes::_ior :
1377         case Bytecodes::_ixor :
1378         case Bytecodes::_iand :
1379           current_frame.pop_stack(
1380             VerificationType::integer_type(), CHECK_VERIFY(this));
1381           // fall through
1382         case Bytecodes::_ineg :
1383           current_frame.pop_stack(
1384             VerificationType::integer_type(), CHECK_VERIFY(this));
1385           current_frame.push_stack(
1386             VerificationType::integer_type(), CHECK_VERIFY(this));
1387           no_control_flow = false; break;
1388         case Bytecodes::_ladd :
1389         case Bytecodes::_lsub :
1390         case Bytecodes::_lmul :
1391         case Bytecodes::_ldiv :
1392         case Bytecodes::_lrem :
1393         case Bytecodes::_land :
1394         case Bytecodes::_lor :
1395         case Bytecodes::_lxor :
1396           current_frame.pop_stack_2(
1397             VerificationType::long2_type(),
1398             VerificationType::long_type(), CHECK_VERIFY(this));
1399           // fall through
1400         case Bytecodes::_lneg :
1401           current_frame.pop_stack_2(
1402             VerificationType::long2_type(),
1403             VerificationType::long_type(), CHECK_VERIFY(this));
1404           current_frame.push_stack_2(
1405             VerificationType::long_type(),
1406             VerificationType::long2_type(), CHECK_VERIFY(this));
1407           no_control_flow = false; break;
1408         case Bytecodes::_lshl :
1409         case Bytecodes::_lshr :
1410         case Bytecodes::_lushr :
1411           current_frame.pop_stack(
1412             VerificationType::integer_type(), CHECK_VERIFY(this));
1413           current_frame.pop_stack_2(
1414             VerificationType::long2_type(),
1415             VerificationType::long_type(), CHECK_VERIFY(this));
1416           current_frame.push_stack_2(
1417             VerificationType::long_type(),
1418             VerificationType::long2_type(), CHECK_VERIFY(this));
1419           no_control_flow = false; break;
1420         case Bytecodes::_fadd :
1421         case Bytecodes::_fsub :
1422         case Bytecodes::_fmul :
1423         case Bytecodes::_fdiv :
1424         case Bytecodes::_frem :
1425           current_frame.pop_stack(
1426             VerificationType::float_type(), CHECK_VERIFY(this));
1427           // fall through
1428         case Bytecodes::_fneg :
1429           current_frame.pop_stack(
1430             VerificationType::float_type(), CHECK_VERIFY(this));
1431           current_frame.push_stack(
1432             VerificationType::float_type(), CHECK_VERIFY(this));
1433           no_control_flow = false; break;
1434         case Bytecodes::_dadd :
1435         case Bytecodes::_dsub :
1436         case Bytecodes::_dmul :
1437         case Bytecodes::_ddiv :
1438         case Bytecodes::_drem :
1439           current_frame.pop_stack_2(
1440             VerificationType::double2_type(),
1441             VerificationType::double_type(), CHECK_VERIFY(this));
1442           // fall through
1443         case Bytecodes::_dneg :
1444           current_frame.pop_stack_2(
1445             VerificationType::double2_type(),
1446             VerificationType::double_type(), CHECK_VERIFY(this));
1447           current_frame.push_stack_2(
1448             VerificationType::double_type(),
1449             VerificationType::double2_type(), CHECK_VERIFY(this));
1450           no_control_flow = false; break;
1451         case Bytecodes::_iinc :
1452           verify_iinc(bcs.get_index(), &current_frame, CHECK_VERIFY(this));
1453           no_control_flow = false; break;
1454         case Bytecodes::_i2l :
1455           type = current_frame.pop_stack(
1456             VerificationType::integer_type(), CHECK_VERIFY(this));
1457           current_frame.push_stack_2(
1458             VerificationType::long_type(),
1459             VerificationType::long2_type(), CHECK_VERIFY(this));
1460           no_control_flow = false; break;
1461        case Bytecodes::_l2i :
1462           current_frame.pop_stack_2(
1463             VerificationType::long2_type(),
1464             VerificationType::long_type(), CHECK_VERIFY(this));
1465           current_frame.push_stack(
1466             VerificationType::integer_type(), CHECK_VERIFY(this));
1467           no_control_flow = false; break;
1468         case Bytecodes::_i2f :
1469           current_frame.pop_stack(
1470             VerificationType::integer_type(), CHECK_VERIFY(this));
1471           current_frame.push_stack(
1472             VerificationType::float_type(), CHECK_VERIFY(this));
1473           no_control_flow = false; break;
1474         case Bytecodes::_i2d :
1475           current_frame.pop_stack(
1476             VerificationType::integer_type(), CHECK_VERIFY(this));
1477           current_frame.push_stack_2(
1478             VerificationType::double_type(),
1479             VerificationType::double2_type(), CHECK_VERIFY(this));
1480           no_control_flow = false; break;
1481         case Bytecodes::_l2f :
1482           current_frame.pop_stack_2(
1483             VerificationType::long2_type(),
1484             VerificationType::long_type(), CHECK_VERIFY(this));
1485           current_frame.push_stack(
1486             VerificationType::float_type(), CHECK_VERIFY(this));
1487           no_control_flow = false; break;
1488         case Bytecodes::_l2d :
1489           current_frame.pop_stack_2(
1490             VerificationType::long2_type(),
1491             VerificationType::long_type(), CHECK_VERIFY(this));
1492           current_frame.push_stack_2(
1493             VerificationType::double_type(),
1494             VerificationType::double2_type(), CHECK_VERIFY(this));
1495           no_control_flow = false; break;
1496         case Bytecodes::_f2i :
1497           current_frame.pop_stack(
1498             VerificationType::float_type(), CHECK_VERIFY(this));
1499           current_frame.push_stack(
1500             VerificationType::integer_type(), CHECK_VERIFY(this));
1501           no_control_flow = false; break;
1502         case Bytecodes::_f2l :
1503           current_frame.pop_stack(
1504             VerificationType::float_type(), CHECK_VERIFY(this));
1505           current_frame.push_stack_2(
1506             VerificationType::long_type(),
1507             VerificationType::long2_type(), CHECK_VERIFY(this));
1508           no_control_flow = false; break;
1509         case Bytecodes::_f2d :
1510           current_frame.pop_stack(
1511             VerificationType::float_type(), CHECK_VERIFY(this));
1512           current_frame.push_stack_2(
1513             VerificationType::double_type(),
1514             VerificationType::double2_type(), CHECK_VERIFY(this));
1515           no_control_flow = false; break;
1516         case Bytecodes::_d2i :
1517           current_frame.pop_stack_2(
1518             VerificationType::double2_type(),
1519             VerificationType::double_type(), CHECK_VERIFY(this));
1520           current_frame.push_stack(
1521             VerificationType::integer_type(), CHECK_VERIFY(this));
1522           no_control_flow = false; break;
1523         case Bytecodes::_d2l :
1524           current_frame.pop_stack_2(
1525             VerificationType::double2_type(),
1526             VerificationType::double_type(), CHECK_VERIFY(this));
1527           current_frame.push_stack_2(
1528             VerificationType::long_type(),
1529             VerificationType::long2_type(), CHECK_VERIFY(this));
1530           no_control_flow = false; break;
1531         case Bytecodes::_d2f :
1532           current_frame.pop_stack_2(
1533             VerificationType::double2_type(),
1534             VerificationType::double_type(), CHECK_VERIFY(this));
1535           current_frame.push_stack(
1536             VerificationType::float_type(), CHECK_VERIFY(this));
1537           no_control_flow = false; break;
1538         case Bytecodes::_i2b :
1539         case Bytecodes::_i2c :
1540         case Bytecodes::_i2s :
1541           current_frame.pop_stack(
1542             VerificationType::integer_type(), CHECK_VERIFY(this));
1543           current_frame.push_stack(
1544             VerificationType::integer_type(), CHECK_VERIFY(this));
1545           no_control_flow = false; break;
1546         case Bytecodes::_lcmp :
1547           current_frame.pop_stack_2(
1548             VerificationType::long2_type(),
1549             VerificationType::long_type(), CHECK_VERIFY(this));
1550           current_frame.pop_stack_2(
1551             VerificationType::long2_type(),
1552             VerificationType::long_type(), CHECK_VERIFY(this));
1553           current_frame.push_stack(
1554             VerificationType::integer_type(), CHECK_VERIFY(this));
1555           no_control_flow = false; break;
1556         case Bytecodes::_fcmpl :
1557         case Bytecodes::_fcmpg :
1558           current_frame.pop_stack(
1559             VerificationType::float_type(), CHECK_VERIFY(this));
1560           current_frame.pop_stack(
1561             VerificationType::float_type(), CHECK_VERIFY(this));
1562           current_frame.push_stack(
1563             VerificationType::integer_type(), CHECK_VERIFY(this));
1564           no_control_flow = false; break;
1565         case Bytecodes::_dcmpl :
1566         case Bytecodes::_dcmpg :
1567           current_frame.pop_stack_2(
1568             VerificationType::double2_type(),
1569             VerificationType::double_type(), CHECK_VERIFY(this));
1570           current_frame.pop_stack_2(
1571             VerificationType::double2_type(),
1572             VerificationType::double_type(), CHECK_VERIFY(this));
1573           current_frame.push_stack(
1574             VerificationType::integer_type(), CHECK_VERIFY(this));
1575           no_control_flow = false; break;
1576         case Bytecodes::_if_icmpeq:
1577         case Bytecodes::_if_icmpne:
1578         case Bytecodes::_if_icmplt:
1579         case Bytecodes::_if_icmpge:
1580         case Bytecodes::_if_icmpgt:
1581         case Bytecodes::_if_icmple:
1582           current_frame.pop_stack(
1583             VerificationType::integer_type(), CHECK_VERIFY(this));
1584           // fall through
1585         case Bytecodes::_ifeq:
1586         case Bytecodes::_ifne:
1587         case Bytecodes::_iflt:
1588         case Bytecodes::_ifge:
1589         case Bytecodes::_ifgt:
1590         case Bytecodes::_ifle:
1591           current_frame.pop_stack(
1592             VerificationType::integer_type(), CHECK_VERIFY(this));
1593           target = bcs.dest();
1594           stackmap_table.check_jump_target(
1595             &current_frame, target, CHECK_VERIFY(this));
1596           no_control_flow = false; break;
1597         case Bytecodes::_if_acmpeq :
1598         case Bytecodes::_if_acmpne :
1599           current_frame.pop_stack(
1600             VerificationType::reference_check(), CHECK_VERIFY(this));
1601           // fall through
1602         case Bytecodes::_ifnull :
1603         case Bytecodes::_ifnonnull :
1604           current_frame.pop_stack(
1605             VerificationType::reference_check(), CHECK_VERIFY(this));
1606           target = bcs.dest();
1607           stackmap_table.check_jump_target
1608             (&current_frame, target, CHECK_VERIFY(this));
1609           no_control_flow = false; break;
1610         case Bytecodes::_goto :
1611           target = bcs.dest();
1612           stackmap_table.check_jump_target(
1613             &current_frame, target, CHECK_VERIFY(this));
1614           no_control_flow = true; break;
1615         case Bytecodes::_goto_w :
1616           target = bcs.dest_w();
1617           stackmap_table.check_jump_target(
1618             &current_frame, target, CHECK_VERIFY(this));
1619           no_control_flow = true; break;
1620         case Bytecodes::_tableswitch :
1621         case Bytecodes::_lookupswitch :
1622           verify_switch(
1623             &bcs, code_length, code_data, &current_frame,
1624             &stackmap_table, CHECK_VERIFY(this));
1625           no_control_flow = true; break;
1626         case Bytecodes::_ireturn :
1627           type = current_frame.pop_stack(
1628             VerificationType::integer_type(), CHECK_VERIFY(this));
1629           verify_return_value(return_type, type, bci,
1630                               &current_frame, CHECK_VERIFY(this));
1631           no_control_flow = true; break;
1632         case Bytecodes::_lreturn :
1633           type2 = current_frame.pop_stack(
1634             VerificationType::long2_type(), CHECK_VERIFY(this));
1635           type = current_frame.pop_stack(
1636             VerificationType::long_type(), CHECK_VERIFY(this));
1637           verify_return_value(return_type, type, bci,
1638                               &current_frame, CHECK_VERIFY(this));
1639           no_control_flow = true; break;
1640         case Bytecodes::_freturn :
1641           type = current_frame.pop_stack(
1642             VerificationType::float_type(), CHECK_VERIFY(this));
1643           verify_return_value(return_type, type, bci,
1644                               &current_frame, CHECK_VERIFY(this));
1645           no_control_flow = true; break;
1646         case Bytecodes::_dreturn :
1647           type2 = current_frame.pop_stack(
1648             VerificationType::double2_type(),  CHECK_VERIFY(this));
1649           type = current_frame.pop_stack(
1650             VerificationType::double_type(), CHECK_VERIFY(this));
1651           verify_return_value(return_type, type, bci,
1652                               &current_frame, CHECK_VERIFY(this));
1653           no_control_flow = true; break;
1654         case Bytecodes::_areturn :
1655           type = current_frame.pop_stack(
1656             VerificationType::reference_check(), CHECK_VERIFY(this));
1657           verify_return_value(return_type, type, bci,
1658                               &current_frame, CHECK_VERIFY(this));
1659           no_control_flow = true; break;
1660         case Bytecodes::_return :
1661           if (return_type != VerificationType::bogus_type()) {
1662             verify_error(ErrorContext::bad_code(bci),
1663                          "Method expects a return value");
1664             return;
1665           }
1666           // Make sure "this" has been initialized if current method is an
1667           // <init>.
1668           if (_method->name() == vmSymbols::object_initializer_name() &&
1669               current_frame.flag_this_uninit()) {
1670             verify_error(ErrorContext::bad_code(bci),
1671                          "Constructor must call super() or this() "
1672                          "before return");
1673             return;
1674           }
1675           no_control_flow = true; break;
1676         case Bytecodes::_getstatic :
1677         case Bytecodes::_putstatic :
1678           // pass TRUE, operand can be an array type for getstatic/putstatic.
1679           verify_field_instructions(
1680             &bcs, &current_frame, cp, true, CHECK_VERIFY(this));
1681           no_control_flow = false; break;
1682         case Bytecodes::_getfield :
1683         case Bytecodes::_putfield :
1684           // pass FALSE, operand can't be an array type for getfield/putfield.
1685           verify_field_instructions(
1686             &bcs, &current_frame, cp, false, CHECK_VERIFY(this));
1687           no_control_flow = false; break;
1688         case Bytecodes::_invokevirtual :
1689         case Bytecodes::_invokespecial :
1690         case Bytecodes::_invokestatic :
1691           verify_invoke_instructions(
1692             &bcs, code_length, &current_frame, (bci >= ex_min && bci < ex_max),
1693             &this_uninit, return_type, cp, &stackmap_table, CHECK_VERIFY(this));
1694           no_control_flow = false; break;
1695         case Bytecodes::_invokeinterface :
1696         case Bytecodes::_invokedynamic :
1697           verify_invoke_instructions(
1698             &bcs, code_length, &current_frame, (bci >= ex_min && bci < ex_max),
1699             &this_uninit, return_type, cp, &stackmap_table, CHECK_VERIFY(this));
1700           no_control_flow = false; break;
1701         case Bytecodes::_new :
1702         {
1703           index = bcs.get_index_u2();
1704           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
1705           VerificationType new_class_type =
1706             cp_index_to_type(index, cp, CHECK_VERIFY(this));
1707           if (!new_class_type.is_object()) {
1708             verify_error(ErrorContext::bad_type(bci,
1709                 TypeOrigin::cp(index, new_class_type)),
1710                 "Illegal new instruction");
1711             return;
1712           }
1713           type = VerificationType::uninitialized_type(bci);
1714           current_frame.push_stack(type, CHECK_VERIFY(this));
1715           no_control_flow = false; break;
1716         }
1717         case Bytecodes::_newarray :
1718           type = get_newarray_type(bcs.get_index(), bci, CHECK_VERIFY(this));
1719           current_frame.pop_stack(
1720             VerificationType::integer_type(),  CHECK_VERIFY(this));
1721           current_frame.push_stack(type, CHECK_VERIFY(this));
1722           no_control_flow = false; break;
1723         case Bytecodes::_anewarray :
1724           verify_anewarray(
1725             bci, bcs.get_index_u2(), cp, &current_frame, CHECK_VERIFY(this));
1726           no_control_flow = false; break;
1727         case Bytecodes::_arraylength :
1728           type = current_frame.pop_stack(
1729             VerificationType::reference_check(), CHECK_VERIFY(this));
1730           if (!(type.is_null() || type.is_array())) {
1731             verify_error(ErrorContext::bad_type(
1732                 bci, current_frame.stack_top_ctx()),
1733                 bad_type_msg, "arraylength");
1734           }
1735           current_frame.push_stack(
1736             VerificationType::integer_type(), CHECK_VERIFY(this));
1737           no_control_flow = false; break;
1738         case Bytecodes::_checkcast :
1739         {
1740           index = bcs.get_index_u2();
1741           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
1742           current_frame.pop_stack(object_type(), CHECK_VERIFY(this));
1743           VerificationType klass_type = cp_index_to_type(
1744             index, cp, CHECK_VERIFY(this));
1745           current_frame.push_stack(klass_type, CHECK_VERIFY(this));
1746           no_control_flow = false; break;
1747         }
1748         case Bytecodes::_instanceof : {
1749           index = bcs.get_index_u2();
1750           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
1751           current_frame.pop_stack(object_type(), CHECK_VERIFY(this));
1752           current_frame.push_stack(
1753             VerificationType::integer_type(), CHECK_VERIFY(this));
1754           no_control_flow = false; break;
1755         }
1756         case Bytecodes::_monitorenter :
1757         case Bytecodes::_monitorexit :
1758           current_frame.pop_stack(
1759             VerificationType::reference_check(), CHECK_VERIFY(this));
1760           no_control_flow = false; break;
1761         case Bytecodes::_multianewarray :
1762         {
1763           index = bcs.get_index_u2();
1764           u2 dim = *(bcs.bcp()+3);
1765           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
1766           VerificationType new_array_type =
1767             cp_index_to_type(index, cp, CHECK_VERIFY(this));
1768           if (!new_array_type.is_array()) {
1769             verify_error(ErrorContext::bad_type(bci,
1770                 TypeOrigin::cp(index, new_array_type)),
1771                 "Illegal constant pool index in multianewarray instruction");
1772             return;
1773           }
1774           if (dim < 1 || new_array_type.dimensions() < dim) {
1775             verify_error(ErrorContext::bad_code(bci),
1776                 "Illegal dimension in multianewarray instruction: %d", dim);
1777             return;
1778           }
1779           for (int i = 0; i < dim; i++) {
1780             current_frame.pop_stack(
1781               VerificationType::integer_type(), CHECK_VERIFY(this));
1782           }
1783           current_frame.push_stack(new_array_type, CHECK_VERIFY(this));
1784           no_control_flow = false; break;
1785         }
1786         case Bytecodes::_athrow :
1787           type = VerificationType::reference_type(
1788             vmSymbols::java_lang_Throwable());
1789           current_frame.pop_stack(type, CHECK_VERIFY(this));
1790           no_control_flow = true; break;
1791         default:
1792           // We only need to check the valid bytecodes in class file.
1793           // And jsr and ret are not in the new class file format in JDK1.5.
1794           verify_error(ErrorContext::bad_code(bci),
1795               "Bad instruction: %02x", opcode);
1796           no_control_flow = false;
1797           return;
1798       }  // end switch
1799     }  // end Merge with the next instruction
1800 
1801     // Look for possible jump target in exception handlers and see if it matches
1802     // current_frame.  Don't do this check if it has already been done (for
1803     // ([a,d,f,i,l]store* opcodes).  This check cannot be done earlier because
1804     // opcodes, such as invokespecial, may set the this_uninit flag.
1805     assert(!(verified_exc_handlers && this_uninit),
1806       "Exception handler targets got verified before this_uninit got set");
1807     if (!verified_exc_handlers && bci >= ex_min && bci < ex_max) {
1808       if (was_recursively_verified()) return;
1809       verify_exception_handler_targets(
1810         bci, this_uninit, &current_frame, &stackmap_table, CHECK_VERIFY(this));
1811     }
1812   } // end while
1813 
1814   // Make sure that control flow does not fall through end of the method
1815   if (!no_control_flow) {
1816     verify_error(ErrorContext::bad_code(code_length),
1817         "Control flow falls through code end");
1818     return;
1819   }
1820 }
1821 
1822 #undef bad_type_message
1823 
1824 char* ClassVerifier::generate_code_data(const methodHandle& m, u4 code_length, TRAPS) {
1825   char* code_data = NEW_RESOURCE_ARRAY(char, code_length);
1826   memset(code_data, 0, sizeof(char) * code_length);
1827   RawBytecodeStream bcs(m);
1828 
1829   while (!bcs.is_last_bytecode()) {
1830     if (bcs.raw_next() != Bytecodes::_illegal) {
1831       int bci = bcs.bci();
1832       if (bcs.raw_code() == Bytecodes::_new) {
1833         code_data[bci] = NEW_OFFSET;
1834       } else {
1835         code_data[bci] = BYTECODE_OFFSET;
1836       }
1837     } else {
1838       verify_error(ErrorContext::bad_code(bcs.bci()), "Bad instruction");
1839       return NULL;
1840     }
1841   }
1842 
1843   return code_data;
1844 }
1845 
1846 // Since this method references the constant pool, call was_recursively_verified()
1847 // before calling this method to make sure a prior class load did not cause the
1848 // current class to get verified.
1849 void ClassVerifier::verify_exception_handler_table(u4 code_length, char* code_data, int& min, int& max, TRAPS) {
1850   ExceptionTable exhandlers(_method());
1851   int exlength = exhandlers.length();
1852   constantPoolHandle cp (THREAD, _method->constants());
1853 
1854   for(int i = 0; i < exlength; i++) {
1855     u2 start_pc = exhandlers.start_pc(i);
1856     u2 end_pc = exhandlers.end_pc(i);
1857     u2 handler_pc = exhandlers.handler_pc(i);
1858     if (start_pc >= code_length || code_data[start_pc] == 0) {
1859       class_format_error("Illegal exception table start_pc %d", start_pc);
1860       return;
1861     }
1862     if (end_pc != code_length) {   // special case: end_pc == code_length
1863       if (end_pc > code_length || code_data[end_pc] == 0) {
1864         class_format_error("Illegal exception table end_pc %d", end_pc);
1865         return;
1866       }
1867     }
1868     if (handler_pc >= code_length || code_data[handler_pc] == 0) {
1869       class_format_error("Illegal exception table handler_pc %d", handler_pc);
1870       return;
1871     }
1872     int catch_type_index = exhandlers.catch_type_index(i);
1873     if (catch_type_index != 0) {
1874       VerificationType catch_type = cp_index_to_type(
1875         catch_type_index, cp, CHECK_VERIFY(this));
1876       VerificationType throwable =
1877         VerificationType::reference_type(vmSymbols::java_lang_Throwable());
1878       bool is_subclass = throwable.is_assignable_from(
1879         catch_type, this, false, CHECK_VERIFY(this));
1880       if (!is_subclass) {
1881         // 4286534: should throw VerifyError according to recent spec change
1882         verify_error(ErrorContext::bad_type(handler_pc,
1883             TypeOrigin::cp(catch_type_index, catch_type),
1884             TypeOrigin::implicit(throwable)),
1885             "Catch type is not a subclass "
1886             "of Throwable in exception handler %d", handler_pc);
1887         return;
1888       }
1889     }
1890     if (start_pc < min) min = start_pc;
1891     if (end_pc > max) max = end_pc;
1892   }
1893 }
1894 
1895 void ClassVerifier::verify_local_variable_table(u4 code_length, char* code_data, TRAPS) {
1896   int localvariable_table_length = _method->localvariable_table_length();
1897   if (localvariable_table_length > 0) {
1898     LocalVariableTableElement* table = _method->localvariable_table_start();
1899     for (int i = 0; i < localvariable_table_length; i++) {
1900       u2 start_bci = table[i].start_bci;
1901       u2 length = table[i].length;
1902 
1903       if (start_bci >= code_length || code_data[start_bci] == 0) {
1904         class_format_error(
1905           "Illegal local variable table start_pc %d", start_bci);
1906         return;
1907       }
1908       u4 end_bci = (u4)(start_bci + length);
1909       if (end_bci != code_length) {
1910         if (end_bci >= code_length || code_data[end_bci] == 0) {
1911           class_format_error( "Illegal local variable table length %d", length);
1912           return;
1913         }
1914       }
1915     }
1916   }
1917 }
1918 
1919 u2 ClassVerifier::verify_stackmap_table(u2 stackmap_index, u2 bci,
1920                                         StackMapFrame* current_frame,
1921                                         StackMapTable* stackmap_table,
1922                                         bool no_control_flow, TRAPS) {
1923   if (stackmap_index < stackmap_table->get_frame_count()) {
1924     u2 this_offset = stackmap_table->get_offset(stackmap_index);
1925     if (no_control_flow && this_offset > bci) {
1926       verify_error(ErrorContext::missing_stackmap(bci),
1927                    "Expecting a stack map frame");
1928       return 0;
1929     }
1930     if (this_offset == bci) {
1931       ErrorContext ctx;
1932       // See if current stack map can be assigned to the frame in table.
1933       // current_frame is the stackmap frame got from the last instruction.
1934       // If matched, current_frame will be updated by this method.
1935       bool matches = stackmap_table->match_stackmap(
1936         current_frame, this_offset, stackmap_index,
1937         !no_control_flow, true, &ctx, CHECK_VERIFY_(this, 0));
1938       if (!matches) {
1939         // report type error
1940         verify_error(ctx, "Instruction type does not match stack map");
1941         return 0;
1942       }
1943       stackmap_index++;
1944     } else if (this_offset < bci) {
1945       // current_offset should have met this_offset.
1946       class_format_error("Bad stack map offset %d", this_offset);
1947       return 0;
1948     }
1949   } else if (no_control_flow) {
1950     verify_error(ErrorContext::bad_code(bci), "Expecting a stack map frame");
1951     return 0;
1952   }
1953   return stackmap_index;
1954 }
1955 
1956 // Since this method references the constant pool, call was_recursively_verified()
1957 // before calling this method to make sure a prior class load did not cause the
1958 // current class to get verified.
1959 void ClassVerifier::verify_exception_handler_targets(u2 bci, bool this_uninit,
1960                                                      StackMapFrame* current_frame,
1961                                                      StackMapTable* stackmap_table, TRAPS) {
1962   constantPoolHandle cp (THREAD, _method->constants());
1963   ExceptionTable exhandlers(_method());
1964   int exlength = exhandlers.length();
1965   for(int i = 0; i < exlength; i++) {
1966     u2 start_pc = exhandlers.start_pc(i);
1967     u2 end_pc = exhandlers.end_pc(i);
1968     u2 handler_pc = exhandlers.handler_pc(i);
1969     int catch_type_index = exhandlers.catch_type_index(i);
1970     if(bci >= start_pc && bci < end_pc) {
1971       u1 flags = current_frame->flags();
1972       if (this_uninit) {  flags |= FLAG_THIS_UNINIT; }
1973       StackMapFrame* new_frame = current_frame->frame_in_exception_handler(flags);
1974       if (catch_type_index != 0) {
1975         if (was_recursively_verified()) return;
1976         // We know that this index refers to a subclass of Throwable
1977         VerificationType catch_type = cp_index_to_type(
1978           catch_type_index, cp, CHECK_VERIFY(this));
1979         new_frame->push_stack(catch_type, CHECK_VERIFY(this));
1980       } else {
1981         VerificationType throwable =
1982           VerificationType::reference_type(vmSymbols::java_lang_Throwable());
1983         new_frame->push_stack(throwable, CHECK_VERIFY(this));
1984       }
1985       ErrorContext ctx;
1986       bool matches = stackmap_table->match_stackmap(
1987         new_frame, handler_pc, true, false, &ctx, CHECK_VERIFY(this));
1988       if (!matches) {
1989         verify_error(ctx, "Stack map does not match the one at "
1990             "exception handler %d", handler_pc);
1991         return;
1992       }
1993     }
1994   }
1995 }
1996 
1997 void ClassVerifier::verify_cp_index(
1998     u2 bci, const constantPoolHandle& cp, int index, TRAPS) {
1999   int nconstants = cp->length();
2000   if ((index <= 0) || (index >= nconstants)) {
2001     verify_error(ErrorContext::bad_cp_index(bci, index),
2002         "Illegal constant pool index %d in class %s",
2003         index, cp->pool_holder()->external_name());
2004     return;
2005   }
2006 }
2007 
2008 void ClassVerifier::verify_cp_type(
2009     u2 bci, int index, const constantPoolHandle& cp, unsigned int types, TRAPS) {
2010 
2011   // In some situations, bytecode rewriting may occur while we're verifying.
2012   // In this case, a constant pool cache exists and some indices refer to that
2013   // instead.  Be sure we don't pick up such indices by accident.
2014   // We must check was_recursively_verified() before we get here.
2015   guarantee(cp->cache() == NULL, "not rewritten yet");
2016 
2017   verify_cp_index(bci, cp, index, CHECK_VERIFY(this));
2018   unsigned int tag = cp->tag_at(index).value();
2019   if ((types & (1 << tag)) == 0) {
2020     verify_error(ErrorContext::bad_cp_index(bci, index),
2021       "Illegal type at constant pool entry %d in class %s",
2022       index, cp->pool_holder()->external_name());
2023     return;
2024   }
2025 }
2026 
2027 void ClassVerifier::verify_cp_class_type(
2028     u2 bci, int index, const constantPoolHandle& cp, TRAPS) {
2029   verify_cp_index(bci, cp, index, CHECK_VERIFY(this));
2030   constantTag tag = cp->tag_at(index);
2031   if (!tag.is_klass() && !tag.is_unresolved_klass()) {
2032     verify_error(ErrorContext::bad_cp_index(bci, index),
2033         "Illegal type at constant pool entry %d in class %s",
2034         index, cp->pool_holder()->external_name());
2035     return;
2036   }
2037 }
2038 
2039 void ClassVerifier::verify_error(ErrorContext ctx, const char* msg, ...) {
2040   stringStream ss;
2041 
2042   ctx.reset_frames();
2043   _exception_type = vmSymbols::java_lang_VerifyError();
2044   _error_context = ctx;
2045   va_list va;
2046   va_start(va, msg);
2047   ss.vprint(msg, va);
2048   va_end(va);
2049   _message = ss.as_string();
2050 #ifdef ASSERT
2051   ResourceMark rm;
2052   const char* exception_name = _exception_type->as_C_string();
2053   Exceptions::debug_check_abort(exception_name, NULL);
2054 #endif // ndef ASSERT
2055 }
2056 
2057 void ClassVerifier::class_format_error(const char* msg, ...) {
2058   stringStream ss;
2059   _exception_type = vmSymbols::java_lang_ClassFormatError();
2060   va_list va;
2061   va_start(va, msg);
2062   ss.vprint(msg, va);
2063   va_end(va);
2064   if (!_method.is_null()) {
2065     ss.print(" in method '");
2066     _method->print_external_name(&ss);
2067     ss.print("'");
2068   }
2069   _message = ss.as_string();
2070 }
2071 
2072 Klass* ClassVerifier::load_class(Symbol* name, TRAPS) {
2073   HandleMark hm(THREAD);
2074   // Get current loader and protection domain first.
2075   oop loader = current_class()->class_loader();
2076   oop protection_domain = current_class()->protection_domain();
2077 
2078   Klass* kls = SystemDictionary::resolve_or_fail(
2079     name, Handle(THREAD, loader), Handle(THREAD, protection_domain),
2080     true, THREAD);
2081 
2082   if (kls != NULL) {
2083     if (log_is_enabled(Debug, class, resolve)) {
2084       Verifier::trace_class_resolution(kls, current_class());
2085     }
2086   }
2087   return kls;
2088 }
2089 
2090 bool ClassVerifier::is_protected_access(InstanceKlass* this_class,
2091                                         Klass* target_class,
2092                                         Symbol* field_name,
2093                                         Symbol* field_sig,
2094                                         bool is_method) {
2095   NoSafepointVerifier nosafepoint;
2096 
2097   // If target class isn't a super class of this class, we don't worry about this case
2098   if (!this_class->is_subclass_of(target_class)) {
2099     return false;
2100   }
2101   // Check if the specified method or field is protected
2102   InstanceKlass* target_instance = InstanceKlass::cast(target_class);
2103   fieldDescriptor fd;
2104   if (is_method) {
2105     Method* m = target_instance->uncached_lookup_method(field_name, field_sig, Klass::find_overpass);
2106     if (m != NULL && m->is_protected()) {
2107       if (!this_class->is_same_class_package(m->method_holder())) {
2108         return true;
2109       }
2110     }
2111   } else {
2112     Klass* member_klass = target_instance->find_field(field_name, field_sig, &fd);
2113     if (member_klass != NULL && fd.is_protected()) {
2114       if (!this_class->is_same_class_package(member_klass)) {
2115         return true;
2116       }
2117     }
2118   }
2119   return false;
2120 }
2121 
2122 void ClassVerifier::verify_ldc(
2123     int opcode, u2 index, StackMapFrame* current_frame,
2124     const constantPoolHandle& cp, u2 bci, TRAPS) {
2125   verify_cp_index(bci, cp, index, CHECK_VERIFY(this));
2126   constantTag tag = cp->tag_at(index);
2127   unsigned int types = 0;
2128   if (opcode == Bytecodes::_ldc || opcode == Bytecodes::_ldc_w) {
2129     if (!tag.is_unresolved_klass()) {
2130       types = (1 << JVM_CONSTANT_Integer) | (1 << JVM_CONSTANT_Float)
2131             | (1 << JVM_CONSTANT_String)  | (1 << JVM_CONSTANT_Class)
2132             | (1 << JVM_CONSTANT_MethodHandle) | (1 << JVM_CONSTANT_MethodType)
2133             | (1 << JVM_CONSTANT_Dynamic);
2134       // Note:  The class file parser already verified the legality of
2135       // MethodHandle and MethodType constants.
2136       verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));
2137     }
2138   } else {
2139     assert(opcode == Bytecodes::_ldc2_w, "must be ldc2_w");
2140     types = (1 << JVM_CONSTANT_Double) | (1 << JVM_CONSTANT_Long)
2141           | (1 << JVM_CONSTANT_Dynamic);
2142     verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));
2143   }
2144   if (tag.is_string() && cp->is_pseudo_string_at(index)) {
2145     current_frame->push_stack(object_type(), CHECK_VERIFY(this));
2146   } else if (tag.is_string()) {
2147     current_frame->push_stack(
2148       VerificationType::reference_type(
2149         vmSymbols::java_lang_String()), CHECK_VERIFY(this));
2150   } else if (tag.is_klass() || tag.is_unresolved_klass()) {
2151     current_frame->push_stack(
2152       VerificationType::reference_type(
2153         vmSymbols::java_lang_Class()), CHECK_VERIFY(this));
2154   } else if (tag.is_int()) {
2155     current_frame->push_stack(
2156       VerificationType::integer_type(), CHECK_VERIFY(this));
2157   } else if (tag.is_float()) {
2158     current_frame->push_stack(
2159       VerificationType::float_type(), CHECK_VERIFY(this));
2160   } else if (tag.is_double()) {
2161     current_frame->push_stack_2(
2162       VerificationType::double_type(),
2163       VerificationType::double2_type(), CHECK_VERIFY(this));
2164   } else if (tag.is_long()) {
2165     current_frame->push_stack_2(
2166       VerificationType::long_type(),
2167       VerificationType::long2_type(), CHECK_VERIFY(this));
2168   } else if (tag.is_method_handle()) {
2169     current_frame->push_stack(
2170       VerificationType::reference_type(
2171         vmSymbols::java_lang_invoke_MethodHandle()), CHECK_VERIFY(this));
2172   } else if (tag.is_method_type()) {
2173     current_frame->push_stack(
2174       VerificationType::reference_type(
2175         vmSymbols::java_lang_invoke_MethodType()), CHECK_VERIFY(this));
2176   } else if (tag.is_dynamic_constant()) {
2177     Symbol* constant_type = cp->uncached_signature_ref_at(index);
2178     // Field signature was checked in ClassFileParser.
2179     assert(SignatureVerifier::is_valid_type_signature(constant_type),
2180            "Invalid type for dynamic constant");
2181     assert(sizeof(VerificationType) == sizeof(uintptr_t),
2182           "buffer type must match VerificationType size");
2183     uintptr_t constant_type_buffer[2];
2184     VerificationType* v_constant_type = (VerificationType*)constant_type_buffer;
2185     SignatureStream sig_stream(constant_type, false);
2186     int n = change_sig_to_verificationType(&sig_stream, v_constant_type);
2187     int opcode_n = (opcode == Bytecodes::_ldc2_w ? 2 : 1);
2188     if (n != opcode_n) {
2189       // wrong kind of ldc; reverify against updated type mask
2190       types &= ~(1 << JVM_CONSTANT_Dynamic);
2191       verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));
2192     }
2193     for (int i = 0; i < n; i++) {
2194       current_frame->push_stack(v_constant_type[i], CHECK_VERIFY(this));
2195     }
2196   } else {
2197     /* Unreachable? verify_cp_type has already validated the cp type. */
2198     verify_error(
2199         ErrorContext::bad_cp_index(bci, index), "Invalid index in ldc");
2200     return;
2201   }
2202 }
2203 
2204 void ClassVerifier::verify_switch(
2205     RawBytecodeStream* bcs, u4 code_length, char* code_data,
2206     StackMapFrame* current_frame, StackMapTable* stackmap_table, TRAPS) {
2207   int bci = bcs->bci();
2208   address bcp = bcs->bcp();
2209   address aligned_bcp = align_up(bcp + 1, jintSize);
2210 
2211   if (_klass->major_version() < NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION) {
2212     // 4639449 & 4647081: padding bytes must be 0
2213     u2 padding_offset = 1;
2214     while ((bcp + padding_offset) < aligned_bcp) {
2215       if(*(bcp + padding_offset) != 0) {
2216         verify_error(ErrorContext::bad_code(bci),
2217                      "Nonzero padding byte in lookupswitch or tableswitch");
2218         return;
2219       }
2220       padding_offset++;
2221     }
2222   }
2223 
2224   int default_offset = (int) Bytes::get_Java_u4(aligned_bcp);
2225   int keys, delta;
2226   current_frame->pop_stack(
2227     VerificationType::integer_type(), CHECK_VERIFY(this));
2228   if (bcs->raw_code() == Bytecodes::_tableswitch) {
2229     jint low = (jint)Bytes::get_Java_u4(aligned_bcp + jintSize);
2230     jint high = (jint)Bytes::get_Java_u4(aligned_bcp + 2*jintSize);
2231     if (low > high) {
2232       verify_error(ErrorContext::bad_code(bci),
2233           "low must be less than or equal to high in tableswitch");
2234       return;
2235     }
2236     keys = high - low + 1;
2237     if (keys < 0) {
2238       verify_error(ErrorContext::bad_code(bci), "too many keys in tableswitch");
2239       return;
2240     }
2241     delta = 1;
2242   } else {
2243     keys = (int)Bytes::get_Java_u4(aligned_bcp + jintSize);
2244     if (keys < 0) {
2245       verify_error(ErrorContext::bad_code(bci),
2246                    "number of keys in lookupswitch less than 0");
2247       return;
2248     }
2249     delta = 2;
2250     // Make sure that the lookupswitch items are sorted
2251     for (int i = 0; i < (keys - 1); i++) {
2252       jint this_key = Bytes::get_Java_u4(aligned_bcp + (2+2*i)*jintSize);
2253       jint next_key = Bytes::get_Java_u4(aligned_bcp + (2+2*i+2)*jintSize);
2254       if (this_key >= next_key) {
2255         verify_error(ErrorContext::bad_code(bci),
2256                      "Bad lookupswitch instruction");
2257         return;
2258       }
2259     }
2260   }
2261   int target = bci + default_offset;
2262   stackmap_table->check_jump_target(current_frame, target, CHECK_VERIFY(this));
2263   for (int i = 0; i < keys; i++) {
2264     // Because check_jump_target() may safepoint, the bytecode could have
2265     // moved, which means 'aligned_bcp' is no good and needs to be recalculated.
2266     aligned_bcp = align_up(bcs->bcp() + 1, jintSize);
2267     target = bci + (jint)Bytes::get_Java_u4(aligned_bcp+(3+i*delta)*jintSize);
2268     stackmap_table->check_jump_target(
2269       current_frame, target, CHECK_VERIFY(this));
2270   }
2271   NOT_PRODUCT(aligned_bcp = NULL);  // no longer valid at this point
2272 }
2273 
2274 bool ClassVerifier::name_in_supers(
2275     Symbol* ref_name, InstanceKlass* current) {
2276   Klass* super = current->super();
2277   while (super != NULL) {
2278     if (super->name() == ref_name) {
2279       return true;
2280     }
2281     super = super->super();
2282   }
2283   return false;
2284 }
2285 
2286 void ClassVerifier::verify_field_instructions(RawBytecodeStream* bcs,
2287                                               StackMapFrame* current_frame,
2288                                               const constantPoolHandle& cp,
2289                                               bool allow_arrays,
2290                                               TRAPS) {
2291   u2 index = bcs->get_index_u2();
2292   verify_cp_type(bcs->bci(), index, cp,
2293       1 << JVM_CONSTANT_Fieldref, CHECK_VERIFY(this));
2294 
2295   // Get field name and signature
2296   Symbol* field_name = cp->name_ref_at(index);
2297   Symbol* field_sig = cp->signature_ref_at(index);
2298 
2299   // Field signature was checked in ClassFileParser.
2300   assert(SignatureVerifier::is_valid_type_signature(field_sig),
2301          "Invalid field signature");
2302 
2303   // Get referenced class type
2304   VerificationType ref_class_type = cp_ref_index_to_type(
2305     index, cp, CHECK_VERIFY(this));
2306   if (!ref_class_type.is_object() &&
2307     (!allow_arrays || !ref_class_type.is_array())) {
2308     verify_error(ErrorContext::bad_type(bcs->bci(),
2309         TypeOrigin::cp(index, ref_class_type)),
2310         "Expecting reference to class in class %s at constant pool index %d",
2311         _klass->external_name(), index);
2312     return;
2313   }
2314   VerificationType target_class_type = ref_class_type;
2315 
2316   assert(sizeof(VerificationType) == sizeof(uintptr_t),
2317         "buffer type must match VerificationType size");
2318   uintptr_t field_type_buffer[2];
2319   VerificationType* field_type = (VerificationType*)field_type_buffer;
2320   // If we make a VerificationType[2] array directly, the compiler calls
2321   // to the c-runtime library to do the allocation instead of just
2322   // stack allocating it.  Plus it would run constructors.  This shows up
2323   // in performance profiles.
2324 
2325   SignatureStream sig_stream(field_sig, false);
2326   VerificationType stack_object_type;
2327   int n = change_sig_to_verificationType(&sig_stream, field_type);
2328   u2 bci = bcs->bci();
2329   bool is_assignable;
2330   switch (bcs->raw_code()) {
2331     case Bytecodes::_getstatic: {
2332       for (int i = 0; i < n; i++) {
2333         current_frame->push_stack(field_type[i], CHECK_VERIFY(this));
2334       }
2335       break;
2336     }
2337     case Bytecodes::_putstatic: {
2338       for (int i = n - 1; i >= 0; i--) {
2339         current_frame->pop_stack(field_type[i], CHECK_VERIFY(this));
2340       }
2341       break;
2342     }
2343     case Bytecodes::_getfield: {
2344       stack_object_type = current_frame->pop_stack(
2345         target_class_type, CHECK_VERIFY(this));
2346       for (int i = 0; i < n; i++) {
2347         current_frame->push_stack(field_type[i], CHECK_VERIFY(this));
2348       }
2349       goto check_protected;
2350     }
2351     case Bytecodes::_putfield: {
2352       for (int i = n - 1; i >= 0; i--) {
2353         current_frame->pop_stack(field_type[i], CHECK_VERIFY(this));
2354       }
2355       stack_object_type = current_frame->pop_stack(CHECK_VERIFY(this));
2356 
2357       // The JVMS 2nd edition allows field initialization before the superclass
2358       // initializer, if the field is defined within the current class.
2359       fieldDescriptor fd;
2360       if (stack_object_type == VerificationType::uninitialized_this_type() &&
2361           target_class_type.equals(current_type()) &&
2362           _klass->find_local_field(field_name, field_sig, &fd)) {
2363         stack_object_type = current_type();
2364       }
2365       is_assignable = target_class_type.is_assignable_from(
2366         stack_object_type, this, false, CHECK_VERIFY(this));
2367       if (!is_assignable) {
2368         verify_error(ErrorContext::bad_type(bci,
2369             current_frame->stack_top_ctx(),
2370             TypeOrigin::cp(index, target_class_type)),
2371             "Bad type on operand stack in putfield");
2372         return;
2373       }
2374     }
2375     check_protected: {
2376       if (_this_type == stack_object_type)
2377         break; // stack_object_type must be assignable to _current_class_type
2378       if (was_recursively_verified()) return;
2379       Symbol* ref_class_name =
2380         cp->klass_name_at(cp->klass_ref_index_at(index));
2381       if (!name_in_supers(ref_class_name, current_class()))
2382         // stack_object_type must be assignable to _current_class_type since:
2383         // 1. stack_object_type must be assignable to ref_class.
2384         // 2. ref_class must be _current_class or a subclass of it. It can't
2385         //    be a superclass of it. See revised JVMS 5.4.4.
2386         break;
2387 
2388       Klass* ref_class_oop = load_class(ref_class_name, CHECK);
2389       if (is_protected_access(current_class(), ref_class_oop, field_name,
2390                               field_sig, false)) {
2391         // It's protected access, check if stack object is assignable to
2392         // current class.
2393         is_assignable = current_type().is_assignable_from(
2394           stack_object_type, this, true, CHECK_VERIFY(this));
2395         if (!is_assignable) {
2396           verify_error(ErrorContext::bad_type(bci,
2397               current_frame->stack_top_ctx(),
2398               TypeOrigin::implicit(current_type())),
2399               "Bad access to protected data in getfield");
2400           return;
2401         }
2402       }
2403       break;
2404     }
2405     default: ShouldNotReachHere();
2406   }
2407 }
2408 
2409 // Look at the method's handlers.  If the bci is in the handler's try block
2410 // then check if the handler_pc is already on the stack.  If not, push it
2411 // unless the handler has already been scanned.
2412 void ClassVerifier::push_handlers(ExceptionTable* exhandlers,
2413                                   GrowableArray<u4>* handler_list,
2414                                   GrowableArray<u4>* handler_stack,
2415                                   u4 bci) {
2416   int exlength = exhandlers->length();
2417   for(int x = 0; x < exlength; x++) {
2418     if (bci >= exhandlers->start_pc(x) && bci < exhandlers->end_pc(x)) {
2419       u4 exhandler_pc = exhandlers->handler_pc(x);
2420       if (!handler_list->contains(exhandler_pc)) {
2421         handler_stack->append_if_missing(exhandler_pc);
2422         handler_list->append(exhandler_pc);
2423       }
2424     }
2425   }
2426 }
2427 
2428 // Return TRUE if all code paths starting with start_bc_offset end in
2429 // bytecode athrow or loop.
2430 bool ClassVerifier::ends_in_athrow(u4 start_bc_offset) {
2431   ResourceMark rm;
2432   // Create bytecode stream.
2433   RawBytecodeStream bcs(method());
2434   u4 code_length = method()->code_size();
2435   bcs.set_start(start_bc_offset);
2436   u4 target;
2437   // Create stack for storing bytecode start offsets for if* and *switch.
2438   GrowableArray<u4>* bci_stack = new GrowableArray<u4>(30);
2439   // Create stack for handlers for try blocks containing this handler.
2440   GrowableArray<u4>* handler_stack = new GrowableArray<u4>(30);
2441   // Create list of handlers that have been pushed onto the handler_stack
2442   // so that handlers embedded inside of their own TRY blocks only get
2443   // scanned once.
2444   GrowableArray<u4>* handler_list = new GrowableArray<u4>(30);
2445   // Create list of visited branch opcodes (goto* and if*).
2446   GrowableArray<u4>* visited_branches = new GrowableArray<u4>(30);
2447   ExceptionTable exhandlers(_method());
2448 
2449   while (true) {
2450     if (bcs.is_last_bytecode()) {
2451       // if no more starting offsets to parse or if at the end of the
2452       // method then return false.
2453       if ((bci_stack->is_empty()) || ((u4)bcs.end_bci() == code_length))
2454         return false;
2455       // Pop a bytecode starting offset and scan from there.
2456       bcs.set_start(bci_stack->pop());
2457     }
2458     Bytecodes::Code opcode = bcs.raw_next();
2459     u4 bci = bcs.bci();
2460 
2461     // If the bytecode is in a TRY block, push its handlers so they
2462     // will get parsed.
2463     push_handlers(&exhandlers, handler_list, handler_stack, bci);
2464 
2465     switch (opcode) {
2466       case Bytecodes::_if_icmpeq:
2467       case Bytecodes::_if_icmpne:
2468       case Bytecodes::_if_icmplt:
2469       case Bytecodes::_if_icmpge:
2470       case Bytecodes::_if_icmpgt:
2471       case Bytecodes::_if_icmple:
2472       case Bytecodes::_ifeq:
2473       case Bytecodes::_ifne:
2474       case Bytecodes::_iflt:
2475       case Bytecodes::_ifge:
2476       case Bytecodes::_ifgt:
2477       case Bytecodes::_ifle:
2478       case Bytecodes::_if_acmpeq:
2479       case Bytecodes::_if_acmpne:
2480       case Bytecodes::_ifnull:
2481       case Bytecodes::_ifnonnull:
2482         target = bcs.dest();
2483         if (visited_branches->contains(bci)) {
2484           if (bci_stack->is_empty()) {
2485             if (handler_stack->is_empty()) {
2486               return true;
2487             } else {
2488               // Parse the catch handlers for try blocks containing athrow.
2489               bcs.set_start(handler_stack->pop());
2490             }
2491           } else {
2492             // Pop a bytecode starting offset and scan from there.
2493             bcs.set_start(bci_stack->pop());
2494           }
2495         } else {
2496           if (target > bci) { // forward branch
2497             if (target >= code_length) return false;
2498             // Push the branch target onto the stack.
2499             bci_stack->push(target);
2500             // then, scan bytecodes starting with next.
2501             bcs.set_start(bcs.next_bci());
2502           } else { // backward branch
2503             // Push bytecode offset following backward branch onto the stack.
2504             bci_stack->push(bcs.next_bci());
2505             // Check bytecodes starting with branch target.
2506             bcs.set_start(target);
2507           }
2508           // Record target so we don't branch here again.
2509           visited_branches->append(bci);
2510         }
2511         break;
2512 
2513       case Bytecodes::_goto:
2514       case Bytecodes::_goto_w:
2515         target = (opcode == Bytecodes::_goto ? bcs.dest() : bcs.dest_w());
2516         if (visited_branches->contains(bci)) {
2517           if (bci_stack->is_empty()) {
2518             if (handler_stack->is_empty()) {
2519               return true;
2520             } else {
2521               // Parse the catch handlers for try blocks containing athrow.
2522               bcs.set_start(handler_stack->pop());
2523             }
2524           } else {
2525             // Been here before, pop new starting offset from stack.
2526             bcs.set_start(bci_stack->pop());
2527           }
2528         } else {
2529           if (target >= code_length) return false;
2530           // Continue scanning from the target onward.
2531           bcs.set_start(target);
2532           // Record target so we don't branch here again.
2533           visited_branches->append(bci);
2534         }
2535         break;
2536 
2537       // Check that all switch alternatives end in 'athrow' bytecodes. Since it
2538       // is  difficult to determine where each switch alternative ends, parse
2539       // each switch alternative until either hit a 'return', 'athrow', or reach
2540       // the end of the method's bytecodes.  This is gross but should be okay
2541       // because:
2542       // 1. tableswitch and lookupswitch byte codes in handlers for ctor explicit
2543       //    constructor invocations should be rare.
2544       // 2. if each switch alternative ends in an athrow then the parsing should be
2545       //    short.  If there is no athrow then it is bogus code, anyway.
2546       case Bytecodes::_lookupswitch:
2547       case Bytecodes::_tableswitch:
2548         {
2549           address aligned_bcp = align_up(bcs.bcp() + 1, jintSize);
2550           u4 default_offset = Bytes::get_Java_u4(aligned_bcp) + bci;
2551           int keys, delta;
2552           if (opcode == Bytecodes::_tableswitch) {
2553             jint low = (jint)Bytes::get_Java_u4(aligned_bcp + jintSize);
2554             jint high = (jint)Bytes::get_Java_u4(aligned_bcp + 2*jintSize);
2555             // This is invalid, but let the regular bytecode verifier
2556             // report this because the user will get a better error message.
2557             if (low > high) return true;
2558             keys = high - low + 1;
2559             delta = 1;
2560           } else {
2561             keys = (int)Bytes::get_Java_u4(aligned_bcp + jintSize);
2562             delta = 2;
2563           }
2564           // Invalid, let the regular bytecode verifier deal with it.
2565           if (keys < 0) return true;
2566 
2567           // Push the offset of the next bytecode onto the stack.
2568           bci_stack->push(bcs.next_bci());
2569 
2570           // Push the switch alternatives onto the stack.
2571           for (int i = 0; i < keys; i++) {
2572             u4 target = bci + (jint)Bytes::get_Java_u4(aligned_bcp+(3+i*delta)*jintSize);
2573             if (target > code_length) return false;
2574             bci_stack->push(target);
2575           }
2576 
2577           // Start bytecode parsing for the switch at the default alternative.
2578           if (default_offset > code_length) return false;
2579           bcs.set_start(default_offset);
2580           break;
2581         }
2582 
2583       case Bytecodes::_return:
2584         return false;
2585 
2586       case Bytecodes::_athrow:
2587         {
2588           if (bci_stack->is_empty()) {
2589             if (handler_stack->is_empty()) {
2590               return true;
2591             } else {
2592               // Parse the catch handlers for try blocks containing athrow.
2593               bcs.set_start(handler_stack->pop());
2594             }
2595           } else {
2596             // Pop a bytecode offset and starting scanning from there.
2597             bcs.set_start(bci_stack->pop());
2598           }
2599         }
2600         break;
2601 
2602       default:
2603         ;
2604     } // end switch
2605   } // end while loop
2606 
2607   return false;
2608 }
2609 
2610 void ClassVerifier::verify_invoke_init(
2611     RawBytecodeStream* bcs, u2 ref_class_index, VerificationType ref_class_type,
2612     StackMapFrame* current_frame, u4 code_length, bool in_try_block,
2613     bool *this_uninit, const constantPoolHandle& cp, StackMapTable* stackmap_table,
2614     TRAPS) {
2615   u2 bci = bcs->bci();
2616   VerificationType type = current_frame->pop_stack(
2617     VerificationType::reference_check(), CHECK_VERIFY(this));
2618   if (type == VerificationType::uninitialized_this_type()) {
2619     // The method must be an <init> method of this class or its superclass
2620     Klass* superk = current_class()->super();
2621     if (ref_class_type.name() != current_class()->name() &&
2622         ref_class_type.name() != superk->name()) {
2623       verify_error(ErrorContext::bad_type(bci,
2624           TypeOrigin::implicit(ref_class_type),
2625           TypeOrigin::implicit(current_type())),
2626           "Bad <init> method call");
2627       return;
2628     }
2629 
2630     // If this invokespecial call is done from inside of a TRY block then make
2631     // sure that all catch clause paths end in a throw.  Otherwise, this can
2632     // result in returning an incomplete object.
2633     if (in_try_block) {
2634       ExceptionTable exhandlers(_method());
2635       int exlength = exhandlers.length();
2636       for(int i = 0; i < exlength; i++) {
2637         u2 start_pc = exhandlers.start_pc(i);
2638         u2 end_pc = exhandlers.end_pc(i);
2639 
2640         if (bci >= start_pc && bci < end_pc) {
2641           if (!ends_in_athrow(exhandlers.handler_pc(i))) {
2642             verify_error(ErrorContext::bad_code(bci),
2643               "Bad <init> method call from after the start of a try block");
2644             return;
2645           } else if (log_is_enabled(Info, verification)) {
2646             ResourceMark rm(THREAD);
2647             log_info(verification)("Survived call to ends_in_athrow(): %s",
2648                                           current_class()->name()->as_C_string());
2649           }
2650         }
2651       }
2652 
2653       // Check the exception handler target stackmaps with the locals from the
2654       // incoming stackmap (before initialize_object() changes them to outgoing
2655       // state).
2656       if (was_recursively_verified()) return;
2657       verify_exception_handler_targets(bci, true, current_frame,
2658                                        stackmap_table, CHECK_VERIFY(this));
2659     } // in_try_block
2660 
2661     current_frame->initialize_object(type, current_type());
2662     *this_uninit = true;
2663   } else if (type.is_uninitialized()) {
2664     u2 new_offset = type.bci();
2665     address new_bcp = bcs->bcp() - bci + new_offset;
2666     if (new_offset > (code_length - 3) || (*new_bcp) != Bytecodes::_new) {
2667       /* Unreachable?  Stack map parsing ensures valid type and new
2668        * instructions have a valid BCI. */
2669       verify_error(ErrorContext::bad_code(new_offset),
2670                    "Expecting new instruction");
2671       return;
2672     }
2673     u2 new_class_index = Bytes::get_Java_u2(new_bcp + 1);
2674     if (was_recursively_verified()) return;
2675     verify_cp_class_type(bci, new_class_index, cp, CHECK_VERIFY(this));
2676 
2677     // The method must be an <init> method of the indicated class
2678     VerificationType new_class_type = cp_index_to_type(
2679       new_class_index, cp, CHECK_VERIFY(this));
2680     if (!new_class_type.equals(ref_class_type)) {
2681       verify_error(ErrorContext::bad_type(bci,
2682           TypeOrigin::cp(new_class_index, new_class_type),
2683           TypeOrigin::cp(ref_class_index, ref_class_type)),
2684           "Call to wrong <init> method");
2685       return;
2686     }
2687     // According to the VM spec, if the referent class is a superclass of the
2688     // current class, and is in a different runtime package, and the method is
2689     // protected, then the objectref must be the current class or a subclass
2690     // of the current class.
2691     VerificationType objectref_type = new_class_type;
2692     if (name_in_supers(ref_class_type.name(), current_class())) {
2693       Klass* ref_klass = load_class(ref_class_type.name(), CHECK);
2694       if (was_recursively_verified()) return;
2695       Method* m = InstanceKlass::cast(ref_klass)->uncached_lookup_method(
2696         vmSymbols::object_initializer_name(),
2697         cp->signature_ref_at(bcs->get_index_u2()),
2698         Klass::find_overpass);
2699       // Do nothing if method is not found.  Let resolution detect the error.
2700       if (m != NULL) {
2701         InstanceKlass* mh = m->method_holder();
2702         if (m->is_protected() && !mh->is_same_class_package(_klass)) {
2703           bool assignable = current_type().is_assignable_from(
2704             objectref_type, this, true, CHECK_VERIFY(this));
2705           if (!assignable) {
2706             verify_error(ErrorContext::bad_type(bci,
2707                 TypeOrigin::cp(new_class_index, objectref_type),
2708                 TypeOrigin::implicit(current_type())),
2709                 "Bad access to protected <init> method");
2710             return;
2711           }
2712         }
2713       }
2714     }
2715     // Check the exception handler target stackmaps with the locals from the
2716     // incoming stackmap (before initialize_object() changes them to outgoing
2717     // state).
2718     if (in_try_block) {
2719       if (was_recursively_verified()) return;
2720       verify_exception_handler_targets(bci, *this_uninit, current_frame,
2721                                        stackmap_table, CHECK_VERIFY(this));
2722     }
2723     current_frame->initialize_object(type, new_class_type);
2724   } else {
2725     verify_error(ErrorContext::bad_type(bci, current_frame->stack_top_ctx()),
2726         "Bad operand type when invoking <init>");
2727     return;
2728   }
2729 }
2730 
2731 bool ClassVerifier::is_same_or_direct_interface(
2732     InstanceKlass* klass,
2733     VerificationType klass_type,
2734     VerificationType ref_class_type) {
2735   if (ref_class_type.equals(klass_type)) return true;
2736   Array<InstanceKlass*>* local_interfaces = klass->local_interfaces();
2737   if (local_interfaces != NULL) {
2738     for (int x = 0; x < local_interfaces->length(); x++) {
2739       InstanceKlass* k = local_interfaces->at(x);
2740       assert (k != NULL && k->is_interface(), "invalid interface");
2741       if (ref_class_type.equals(VerificationType::reference_type(k->name()))) {
2742         return true;
2743       }
2744     }
2745   }
2746   return false;
2747 }
2748 
2749 void ClassVerifier::verify_invoke_instructions(
2750     RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame,
2751     bool in_try_block, bool *this_uninit, VerificationType return_type,
2752     const constantPoolHandle& cp, StackMapTable* stackmap_table, TRAPS) {
2753   // Make sure the constant pool item is the right type
2754   u2 index = bcs->get_index_u2();
2755   Bytecodes::Code opcode = bcs->raw_code();
2756   unsigned int types = 0;
2757   switch (opcode) {
2758     case Bytecodes::_invokeinterface:
2759       types = 1 << JVM_CONSTANT_InterfaceMethodref;
2760       break;
2761     case Bytecodes::_invokedynamic:
2762       types = 1 << JVM_CONSTANT_InvokeDynamic;
2763       break;
2764     case Bytecodes::_invokespecial:
2765     case Bytecodes::_invokestatic:
2766       types = (_klass->major_version() < STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION) ?
2767         (1 << JVM_CONSTANT_Methodref) :
2768         ((1 << JVM_CONSTANT_InterfaceMethodref) | (1 << JVM_CONSTANT_Methodref));
2769       break;
2770     default:
2771       types = 1 << JVM_CONSTANT_Methodref;
2772   }
2773   verify_cp_type(bcs->bci(), index, cp, types, CHECK_VERIFY(this));
2774 
2775   // Get method name and signature
2776   Symbol* method_name = cp->name_ref_at(index);
2777   Symbol* method_sig = cp->signature_ref_at(index);
2778 
2779   // Method signature was checked in ClassFileParser.
2780   assert(SignatureVerifier::is_valid_method_signature(method_sig),
2781          "Invalid method signature");
2782 
2783   // Get referenced class type
2784   VerificationType ref_class_type;
2785   if (opcode == Bytecodes::_invokedynamic) {
2786     if (_klass->major_version() < Verifier::INVOKEDYNAMIC_MAJOR_VERSION) {
2787       class_format_error(
2788         "invokedynamic instructions not supported by this class file version (%d), class %s",
2789         _klass->major_version(), _klass->external_name());
2790       return;
2791     }
2792   } else {
2793     ref_class_type = cp_ref_index_to_type(index, cp, CHECK_VERIFY(this));
2794   }
2795 
2796   assert(sizeof(VerificationType) == sizeof(uintptr_t),
2797         "buffer type must match VerificationType size");
2798 
2799   // Get the UTF8 index for this signature.
2800   int sig_index = cp->signature_ref_index_at(cp->name_and_type_ref_index_at(index));
2801 
2802   // Get the signature's verification types.
2803   sig_as_verification_types* mth_sig_verif_types;
2804   sig_as_verification_types** mth_sig_verif_types_ptr = method_signatures_table()->get(sig_index);
2805   if (mth_sig_verif_types_ptr != NULL) {
2806     // Found the entry for the signature's verification types in the hash table.
2807     mth_sig_verif_types = *mth_sig_verif_types_ptr;
2808     assert(mth_sig_verif_types != NULL, "Unexpected NULL sig_as_verification_types value");
2809   } else {
2810     // Not found, add the entry to the table.
2811     GrowableArray<VerificationType>* verif_types = new GrowableArray<VerificationType>(10);
2812     mth_sig_verif_types = new sig_as_verification_types(verif_types);
2813     create_method_sig_entry(mth_sig_verif_types, sig_index, CHECK_VERIFY(this));
2814   }
2815 
2816   // Get the number of arguments for this signature.
2817   int nargs = mth_sig_verif_types->num_args();
2818 
2819   // Check instruction operands
2820   u2 bci = bcs->bci();
2821   if (opcode == Bytecodes::_invokeinterface) {
2822     address bcp = bcs->bcp();
2823     // 4905268: count operand in invokeinterface should be nargs+1, not nargs.
2824     // JSR202 spec: The count operand of an invokeinterface instruction is valid if it is
2825     // the difference between the size of the operand stack before and after the instruction
2826     // executes.
2827     if (*(bcp+3) != (nargs+1)) {
2828       verify_error(ErrorContext::bad_code(bci),
2829           "Inconsistent args count operand in invokeinterface");
2830       return;
2831     }
2832     if (*(bcp+4) != 0) {
2833       verify_error(ErrorContext::bad_code(bci),
2834           "Fourth operand byte of invokeinterface must be zero");
2835       return;
2836     }
2837   }
2838 
2839   if (opcode == Bytecodes::_invokedynamic) {
2840     address bcp = bcs->bcp();
2841     if (*(bcp+3) != 0 || *(bcp+4) != 0) {
2842       verify_error(ErrorContext::bad_code(bci),
2843           "Third and fourth operand bytes of invokedynamic must be zero");
2844       return;
2845     }
2846   }
2847 
2848   if (method_name->char_at(0) == '<') {
2849     // Make sure <init> can only be invoked by invokespecial
2850     if (opcode != Bytecodes::_invokespecial ||
2851         method_name != vmSymbols::object_initializer_name()) {
2852       verify_error(ErrorContext::bad_code(bci),
2853           "Illegal call to internal method");
2854       return;
2855     }
2856   } else if (opcode == Bytecodes::_invokespecial
2857              && !is_same_or_direct_interface(current_class(), current_type(), ref_class_type)
2858              && !ref_class_type.equals(VerificationType::reference_type(
2859                   current_class()->super()->name()))) {
2860     bool subtype = false;
2861     bool have_imr_indirect = cp->tag_at(index).value() == JVM_CONSTANT_InterfaceMethodref;
2862     if (!current_class()->is_unsafe_anonymous()) {
2863       subtype = ref_class_type.is_assignable_from(
2864                  current_type(), this, false, CHECK_VERIFY(this));
2865     } else {
2866       VerificationType unsafe_anonymous_host_type =
2867                         VerificationType::reference_type(current_class()->unsafe_anonymous_host()->name());
2868       subtype = ref_class_type.is_assignable_from(unsafe_anonymous_host_type, this, false, CHECK_VERIFY(this));
2869 
2870       // If invokespecial of IMR, need to recheck for same or
2871       // direct interface relative to the host class
2872       have_imr_indirect = (have_imr_indirect &&
2873                            !is_same_or_direct_interface(
2874                              current_class()->unsafe_anonymous_host(),
2875                              unsafe_anonymous_host_type, ref_class_type));
2876     }
2877     if (!subtype) {
2878       verify_error(ErrorContext::bad_code(bci),
2879           "Bad invokespecial instruction: "
2880           "current class isn't assignable to reference class.");
2881        return;
2882     } else if (have_imr_indirect) {
2883       verify_error(ErrorContext::bad_code(bci),
2884           "Bad invokespecial instruction: "
2885           "interface method reference is in an indirect superinterface.");
2886       return;
2887     }
2888 
2889   }
2890 
2891   // Get the verification types for the method's arguments.
2892   GrowableArray<VerificationType>* sig_verif_types = mth_sig_verif_types->sig_verif_types();
2893   assert(sig_verif_types != NULL, "Missing signature's array of verification types");
2894   // Match method descriptor with operand stack
2895   // The arguments are on the stack in descending order.
2896   for (int i = nargs - 1; i >= 0; i--) { // Run backwards
2897     current_frame->pop_stack(sig_verif_types->at(i), CHECK_VERIFY(this));
2898   }
2899 
2900   // Check objectref on operand stack
2901   if (opcode != Bytecodes::_invokestatic &&
2902       opcode != Bytecodes::_invokedynamic) {
2903     if (method_name == vmSymbols::object_initializer_name()) {  // <init> method
2904       verify_invoke_init(bcs, index, ref_class_type, current_frame,
2905         code_length, in_try_block, this_uninit, cp, stackmap_table,
2906         CHECK_VERIFY(this));
2907       if (was_recursively_verified()) return;
2908     } else {   // other methods
2909       // Ensures that target class is assignable to method class.
2910       if (opcode == Bytecodes::_invokespecial) {
2911         if (!current_class()->is_unsafe_anonymous()) {
2912           current_frame->pop_stack(current_type(), CHECK_VERIFY(this));
2913         } else {
2914           // anonymous class invokespecial calls: check if the
2915           // objectref is a subtype of the unsafe_anonymous_host of the current class
2916           // to allow an anonymous class to reference methods in the unsafe_anonymous_host
2917           VerificationType top = current_frame->pop_stack(CHECK_VERIFY(this));
2918           VerificationType hosttype =
2919             VerificationType::reference_type(current_class()->unsafe_anonymous_host()->name());
2920           bool subtype = hosttype.is_assignable_from(top, this, false, CHECK_VERIFY(this));
2921           if (!subtype) {
2922             verify_error( ErrorContext::bad_type(current_frame->offset(),
2923               current_frame->stack_top_ctx(),
2924               TypeOrigin::implicit(top)),
2925               "Bad type on operand stack");
2926             return;
2927           }
2928         }
2929       } else if (opcode == Bytecodes::_invokevirtual) {
2930         VerificationType stack_object_type =
2931           current_frame->pop_stack(ref_class_type, CHECK_VERIFY(this));
2932         if (current_type() != stack_object_type) {
2933           if (was_recursively_verified()) return;
2934           assert(cp->cache() == NULL, "not rewritten yet");
2935           Symbol* ref_class_name =
2936             cp->klass_name_at(cp->klass_ref_index_at(index));
2937           // See the comments in verify_field_instructions() for
2938           // the rationale behind this.
2939           if (name_in_supers(ref_class_name, current_class())) {
2940             Klass* ref_class = load_class(ref_class_name, CHECK);
2941             if (is_protected_access(
2942                   _klass, ref_class, method_name, method_sig, true)) {
2943               // It's protected access, check if stack object is
2944               // assignable to current class.
2945               bool is_assignable = current_type().is_assignable_from(
2946                 stack_object_type, this, true, CHECK_VERIFY(this));
2947               if (!is_assignable) {
2948                 if (ref_class_type.name() == vmSymbols::java_lang_Object()
2949                     && stack_object_type.is_array()
2950                     && method_name == vmSymbols::clone_name()) {
2951                   // Special case: arrays pretend to implement public Object
2952                   // clone().
2953                 } else {
2954                   verify_error(ErrorContext::bad_type(bci,
2955                       current_frame->stack_top_ctx(),
2956                       TypeOrigin::implicit(current_type())),
2957                       "Bad access to protected data in invokevirtual");
2958                   return;
2959                 }
2960               }
2961             }
2962           }
2963         }
2964       } else {
2965         assert(opcode == Bytecodes::_invokeinterface, "Unexpected opcode encountered");
2966         current_frame->pop_stack(ref_class_type, CHECK_VERIFY(this));
2967       }
2968     }
2969   }
2970   // Push the result type.
2971   int sig_verif_types_len = sig_verif_types->length();
2972   if (sig_verif_types_len > nargs) {  // There's a return type
2973     if (method_name == vmSymbols::object_initializer_name()) {
2974       // <init> method must have a void return type
2975       /* Unreachable?  Class file parser verifies that methods with '<' have
2976        * void return */
2977       verify_error(ErrorContext::bad_code(bci),
2978           "Return type must be void in <init> method");
2979       return;
2980     }
2981 
2982     assert(sig_verif_types_len <= nargs + 2,
2983            "Signature verification types array return type is bogus");
2984     for (int i = nargs; i < sig_verif_types_len; i++) {
2985       assert(i == nargs || sig_verif_types->at(i).is_long2() ||
2986              sig_verif_types->at(i).is_double2(), "Unexpected return verificationType");
2987       current_frame->push_stack(sig_verif_types->at(i), CHECK_VERIFY(this));
2988     }
2989   }
2990 }
2991 
2992 VerificationType ClassVerifier::get_newarray_type(
2993     u2 index, u2 bci, TRAPS) {
2994   const char* from_bt[] = {
2995     NULL, NULL, NULL, NULL, "[Z", "[C", "[F", "[D", "[B", "[S", "[I", "[J",
2996   };
2997   if (index < T_BOOLEAN || index > T_LONG) {
2998     verify_error(ErrorContext::bad_code(bci), "Illegal newarray instruction");
2999     return VerificationType::bogus_type();
3000   }
3001 
3002   // from_bt[index] contains the array signature which has a length of 2
3003   Symbol* sig = create_temporary_symbol(from_bt[index], 2);
3004   return VerificationType::reference_type(sig);
3005 }
3006 
3007 void ClassVerifier::verify_anewarray(
3008     u2 bci, u2 index, const constantPoolHandle& cp,
3009     StackMapFrame* current_frame, TRAPS) {
3010   verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
3011   current_frame->pop_stack(
3012     VerificationType::integer_type(), CHECK_VERIFY(this));
3013 
3014   if (was_recursively_verified()) return;
3015   VerificationType component_type =
3016     cp_index_to_type(index, cp, CHECK_VERIFY(this));
3017   int length;
3018   char* arr_sig_str;
3019   if (component_type.is_array()) {     // it's an array
3020     const char* component_name = component_type.name()->as_utf8();
3021     // Check for more than MAX_ARRAY_DIMENSIONS
3022     length = (int)strlen(component_name);
3023     if (length > MAX_ARRAY_DIMENSIONS &&
3024         component_name[MAX_ARRAY_DIMENSIONS - 1] == '[') {
3025       verify_error(ErrorContext::bad_code(bci),
3026         "Illegal anewarray instruction, array has more than 255 dimensions");
3027     }
3028     // add one dimension to component
3029     length++;
3030     arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length + 1);
3031     int n = os::snprintf(arr_sig_str, length + 1, "[%s", component_name);
3032     assert(n == length, "Unexpected number of characters in string");
3033   } else {         // it's an object or interface
3034     const char* component_name = component_type.name()->as_utf8();
3035     // add one dimension to component with 'L' prepended and ';' postpended.
3036     length = (int)strlen(component_name) + 3;
3037     arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length + 1);
3038     int n = os::snprintf(arr_sig_str, length + 1, "[L%s;", component_name);
3039     assert(n == length, "Unexpected number of characters in string");
3040   }
3041   Symbol* arr_sig = create_temporary_symbol(arr_sig_str, length);
3042   VerificationType new_array_type = VerificationType::reference_type(arr_sig);
3043   current_frame->push_stack(new_array_type, CHECK_VERIFY(this));
3044 }
3045 
3046 void ClassVerifier::verify_iload(u2 index, StackMapFrame* current_frame, TRAPS) {
3047   current_frame->get_local(
3048     index, VerificationType::integer_type(), CHECK_VERIFY(this));
3049   current_frame->push_stack(
3050     VerificationType::integer_type(), CHECK_VERIFY(this));
3051 }
3052 
3053 void ClassVerifier::verify_lload(u2 index, StackMapFrame* current_frame, TRAPS) {
3054   current_frame->get_local_2(
3055     index, VerificationType::long_type(),
3056     VerificationType::long2_type(), CHECK_VERIFY(this));
3057   current_frame->push_stack_2(
3058     VerificationType::long_type(),
3059     VerificationType::long2_type(), CHECK_VERIFY(this));
3060 }
3061 
3062 void ClassVerifier::verify_fload(u2 index, StackMapFrame* current_frame, TRAPS) {
3063   current_frame->get_local(
3064     index, VerificationType::float_type(), CHECK_VERIFY(this));
3065   current_frame->push_stack(
3066     VerificationType::float_type(), CHECK_VERIFY(this));
3067 }
3068 
3069 void ClassVerifier::verify_dload(u2 index, StackMapFrame* current_frame, TRAPS) {
3070   current_frame->get_local_2(
3071     index, VerificationType::double_type(),
3072     VerificationType::double2_type(), CHECK_VERIFY(this));
3073   current_frame->push_stack_2(
3074     VerificationType::double_type(),
3075     VerificationType::double2_type(), CHECK_VERIFY(this));
3076 }
3077 
3078 void ClassVerifier::verify_aload(u2 index, StackMapFrame* current_frame, TRAPS) {
3079   VerificationType type = current_frame->get_local(
3080     index, VerificationType::reference_check(), CHECK_VERIFY(this));
3081   current_frame->push_stack(type, CHECK_VERIFY(this));
3082 }
3083 
3084 void ClassVerifier::verify_istore(u2 index, StackMapFrame* current_frame, TRAPS) {
3085   current_frame->pop_stack(
3086     VerificationType::integer_type(), CHECK_VERIFY(this));
3087   current_frame->set_local(
3088     index, VerificationType::integer_type(), CHECK_VERIFY(this));
3089 }
3090 
3091 void ClassVerifier::verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS) {
3092   current_frame->pop_stack_2(
3093     VerificationType::long2_type(),
3094     VerificationType::long_type(), CHECK_VERIFY(this));
3095   current_frame->set_local_2(
3096     index, VerificationType::long_type(),
3097     VerificationType::long2_type(), CHECK_VERIFY(this));
3098 }
3099 
3100 void ClassVerifier::verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS) {
3101   current_frame->pop_stack(VerificationType::float_type(), CHECK_VERIFY(this));
3102   current_frame->set_local(
3103     index, VerificationType::float_type(), CHECK_VERIFY(this));
3104 }
3105 
3106 void ClassVerifier::verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS) {
3107   current_frame->pop_stack_2(
3108     VerificationType::double2_type(),
3109     VerificationType::double_type(), CHECK_VERIFY(this));
3110   current_frame->set_local_2(
3111     index, VerificationType::double_type(),
3112     VerificationType::double2_type(), CHECK_VERIFY(this));
3113 }
3114 
3115 void ClassVerifier::verify_astore(u2 index, StackMapFrame* current_frame, TRAPS) {
3116   VerificationType type = current_frame->pop_stack(
3117     VerificationType::reference_check(), CHECK_VERIFY(this));
3118   current_frame->set_local(index, type, CHECK_VERIFY(this));
3119 }
3120 
3121 void ClassVerifier::verify_iinc(u2 index, StackMapFrame* current_frame, TRAPS) {
3122   VerificationType type = current_frame->get_local(
3123     index, VerificationType::integer_type(), CHECK_VERIFY(this));
3124   current_frame->set_local(index, type, CHECK_VERIFY(this));
3125 }
3126 
3127 void ClassVerifier::verify_return_value(
3128     VerificationType return_type, VerificationType type, u2 bci,
3129     StackMapFrame* current_frame, TRAPS) {
3130   if (return_type == VerificationType::bogus_type()) {
3131     verify_error(ErrorContext::bad_type(bci,
3132         current_frame->stack_top_ctx(), TypeOrigin::signature(return_type)),
3133         "Method expects a return value");
3134     return;
3135   }
3136   bool match = return_type.is_assignable_from(type, this, false, CHECK_VERIFY(this));
3137   if (!match) {
3138     verify_error(ErrorContext::bad_type(bci,
3139         current_frame->stack_top_ctx(), TypeOrigin::signature(return_type)),
3140         "Bad return type");
3141     return;
3142   }
3143 }
3144 
3145 // The verifier creates symbols which are substrings of Symbols.
3146 // These are stored in the verifier until the end of verification so that
3147 // they can be reference counted.
3148 Symbol* ClassVerifier::create_temporary_symbol(const Symbol *s, int begin,
3149                                                int end) {
3150   const char* name = (const char*)s->base() + begin;
3151   int length = end - begin;
3152   return create_temporary_symbol(name, length);
3153 }
3154 
3155 Symbol* ClassVerifier::create_temporary_symbol(const char *name, int length) {
3156   // Quick deduplication check
3157   if (_previous_symbol != NULL && _previous_symbol->equals(name, length)) {
3158     return _previous_symbol;
3159   }
3160   Symbol* sym = SymbolTable::new_symbol(name, length);
3161   if (!sym->is_permanent()) {
3162     if (_symbols == NULL) {
3163       _symbols = new GrowableArray<Symbol*>(50, 0, NULL);
3164     }
3165     _symbols->push(sym);
3166   }
3167   _previous_symbol = sym;
3168   return sym;
3169 }