Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.

  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

  *

  * This code is free software; you can redistribute it and/or modify it

  * under the terms of the GNU General Public License version 2 only, as

  * published by the Free Software Foundation.

  *

  * This code is distributed in the hope that it will be useful, but WITHOUT

  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

  * version 2 for more details (a copy is included in the LICENSE file that

  * accompanied this code).

  *

  * You should have received a copy of the GNU General Public License version

  * 2 along with this work; if not, write to the Free Software Foundation,

  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

  * or visit www.oracle.com if you need additional information or have any

  * questions.

  *

  */

 /*

  * This file has been modified by Loongson Technology in 2015. These

  * modifications are Copyright (c) 2015 Loongson Technology, and are made

  * available on the same license terms set forth above.

  */

 #include "precompiled.hpp"

 #include "classfile/classFileStream.hpp"

 #include "classfile/javaClasses.hpp"

 #include "classfile/stackMapTable.hpp"

 #include "classfile/stackMapFrame.hpp"

 #include "classfile/stackMapTableFormat.hpp"

 #include "classfile/systemDictionary.hpp"

 #include "classfile/verifier.hpp"

 #include "classfile/vmSymbols.hpp"

 #include "interpreter/bytecodes.hpp"

 #include "interpreter/bytecodeStream.hpp"

 #include "memory/oopFactory.hpp"

 #include "memory/resourceArea.hpp"

 #include "oops/instanceKlass.hpp"

 #include "oops/oop.inline.hpp"

 #include "oops/typeArrayOop.hpp"

 #include "prims/jvm.h"

 #include "runtime/fieldDescriptor.hpp"

 #include "runtime/handles.inline.hpp"

 #include "runtime/interfaceSupport.hpp"

 #include "runtime/javaCalls.hpp"

 #include "runtime/orderAccess.inline.hpp"

 #include "runtime/os.hpp"

 #ifdef TARGET_ARCH_x86

 # include "bytes_x86.hpp"

 #endif

 #ifdef TARGET_ARCH_mips

 # include "bytes_mips.hpp"

 #endif

 #ifdef TARGET_ARCH_sparc

 # include "bytes_sparc.hpp"

 #endif

 #ifdef TARGET_ARCH_zero

 # include "bytes_zero.hpp"

 #endif

 #ifdef TARGET_ARCH_arm

 # include "bytes_arm.hpp"

 #endif

 #ifdef TARGET_ARCH_ppc

 # include "bytes_ppc.hpp"

 #endif

 #define NOFAILOVER_MAJOR_VERSION                       51

 #define NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION  51

 #define STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION       52

 // Access to external entry for VerifyClassCodes - old byte code verifier

 extern "C" {

   typedef jboolean (*verify_byte_codes_fn_t)(JNIEnv *, jclass, char *, jint);

   typedef jboolean (*verify_byte_codes_fn_new_t)(JNIEnv *, jclass, char *, jint, jint);

 }

 static void* volatile _verify_byte_codes_fn = NULL;

 static volatile jint _is_new_verify_byte_codes_fn = (jint) true;

 static void* verify_byte_codes_fn() {

   if (_verify_byte_codes_fn == NULL) {

     void *lib_handle = os::native_java_library();

     void *func = os::dll_lookup(lib_handle, "VerifyClassCodesForMajorVersion");

     OrderAccess::release_store_ptr(&_verify_byte_codes_fn, func);

     if (func == NULL) {

       OrderAccess::release_store(&_is_new_verify_byte_codes_fn, false);

       func = os::dll_lookup(lib_handle, "VerifyClassCodes");

       OrderAccess::release_store_ptr(&_verify_byte_codes_fn, func);

     }

   }

   return (void*)_verify_byte_codes_fn;

 }

 // Methods in Verifier

 bool Verifier::should_verify_for(oop class_loader, bool should_verify_class) {

   return (class_loader == NULL || !should_verify_class) ?

     BytecodeVerificationLocal : BytecodeVerificationRemote;

 }

 bool Verifier::relax_verify_for(oop loader) {

   bool trusted = java_lang_ClassLoader::is_trusted_loader(loader);

   bool need_verify =

     // verifyAll

     (BytecodeVerificationLocal && BytecodeVerificationRemote) ||

     // verifyRemote

     (!BytecodeVerificationLocal && BytecodeVerificationRemote && !trusted);

   return !need_verify;

 }

 bool Verifier::verify(instanceKlassHandle klass, Verifier::Mode mode, bool should_verify_class, TRAPS) {

   HandleMark hm;

   ResourceMark rm(THREAD);

   Symbol* exception_name = NULL;

   const size_t message_buffer_len = klass->name()->utf8_length() + 1024;

   char* message_buffer = NEW_RESOURCE_ARRAY(char, message_buffer_len);

   char* exception_message = message_buffer;

   const char* klassName = klass->external_name();

   bool can_failover = FailOverToOldVerifier &&

       klass->major_version() < NOFAILOVER_MAJOR_VERSION;

   // If the class should be verified, first see if we can use the split

   // verifier.  If not, or if verification fails and FailOverToOldVerifier

   // is set, then call the inference verifier.

   if (is_eligible_for_verification(klass, should_verify_class)) {

     if (TraceClassInitialization) {

       tty->print_cr("Start class verification for: %s", klassName);

     }

     if (klass->major_version() >= STACKMAP_ATTRIBUTE_MAJOR_VERSION) {

       ClassVerifier split_verifier(klass, THREAD);

       split_verifier.verify_class(THREAD);

       exception_name = split_verifier.result();

       if (can_failover && !HAS_PENDING_EXCEPTION &&

           (exception_name == vmSymbols::java_lang_VerifyError() ||

            exception_name == vmSymbols::java_lang_ClassFormatError())) {

         if (TraceClassInitialization || VerboseVerification) {

           tty->print_cr(

             "Fail over class verification to old verifier for: %s", klassName);

         }

         exception_name = inference_verify(

           klass, message_buffer, message_buffer_len, THREAD);

       }

       if (exception_name != NULL) {

         exception_message = split_verifier.exception_message();

       }

     } else {

       exception_name = inference_verify(

           klass, message_buffer, message_buffer_len, THREAD);

     }

     if (TraceClassInitialization || VerboseVerification) {

       if (HAS_PENDING_EXCEPTION) {

         tty->print("Verification for %s has", klassName);

         tty->print_cr(" exception pending %s ",

           InstanceKlass::cast(PENDING_EXCEPTION->klass())->external_name());

       } else if (exception_name != NULL) {

         tty->print_cr("Verification for %s failed", klassName);

       }

       tty->print_cr("End class verification for: %s", klassName);

     }

   }

   if (HAS_PENDING_EXCEPTION) {

     return false; // use the existing exception

   } else if (exception_name == NULL) {

     return true; // verifcation succeeded

   } else { // VerifyError or ClassFormatError to be created and thrown

     ResourceMark rm(THREAD);

     instanceKlassHandle kls =

       SystemDictionary::resolve_or_fail(exception_name, true, CHECK_false);

     while (!kls.is_null()) {

       if (kls == klass) {

         // If the class being verified is the exception we're creating

         // or one of it's superclasses, we're in trouble and are going

         // to infinitely recurse when we try to initialize the exception.

         // So bail out here by throwing the preallocated VM error.

         THROW_OOP_(Universe::virtual_machine_error_instance(), false);

       }

       kls = kls->super();

     }

     message_buffer[message_buffer_len - 1] = '\0'; // just to be sure

     THROW_MSG_(exception_name, exception_message, false);

   }

 }

 bool Verifier::is_eligible_for_verification(instanceKlassHandle klass, bool should_verify_class) {

   Symbol* name = klass->name();

   Klass* refl_magic_klass = SystemDictionary::reflect_MagicAccessorImpl_klass();

   bool is_reflect = refl_magic_klass != NULL && klass->is_subtype_of(refl_magic_klass);

   return (should_verify_for(klass->class_loader(), should_verify_class) &&

     // return if the class is a bootstrapping class

     // or defineClass specified not to verify by default (flags override passed arg)

     // We need to skip the following four for bootstraping

     name != vmSymbols::java_lang_Object() &&

     name != vmSymbols::java_lang_Class() &&

     name != vmSymbols::java_lang_String() &&

     name != vmSymbols::java_lang_Throwable() &&

     // Can not verify the bytecodes for shared classes because they have

     // already been rewritten to contain constant pool cache indices,

     // which the verifier can't understand.

     // Shared classes shouldn't have stackmaps either.

     !klass()->is_shared() &&

     // As of the fix for 4486457 we disable verification for all of the

     // dynamically-generated bytecodes associated with the 1.4

     // reflection implementation, not just those associated with

     // sun/reflect/SerializationConstructorAccessor.

     // NOTE: this is called too early in the bootstrapping process to be

     // guarded by Universe::is_gte_jdk14x_version()/UseNewReflection.

     // Also for lambda generated code, gte jdk8

     (!is_reflect || VerifyReflectionBytecodes));

 }

 Symbol* Verifier::inference_verify(

     instanceKlassHandle klass, char* message, size_t message_len, TRAPS) {

   JavaThread* thread = (JavaThread*)THREAD;

   JNIEnv *env = thread->jni_environment();

   void* verify_func = verify_byte_codes_fn();

   if (verify_func == NULL) {

     jio_snprintf(message, message_len, "Could not link verifier");

     return vmSymbols::java_lang_VerifyError();

   }

   ResourceMark rm(THREAD);

   if (VerboseVerification) {

     tty->print_cr("Verifying class %s with old format", klass->external_name());

   }

   jclass cls = (jclass) JNIHandles::make_local(env, klass->java_mirror());

   jint result;

   {

     HandleMark hm(thread);

     ThreadToNativeFromVM ttn(thread);

     // ThreadToNativeFromVM takes care of changing thread_state, so safepoint

     // code knows that we have left the VM

     if (_is_new_verify_byte_codes_fn) {

       verify_byte_codes_fn_new_t func =

         CAST_TO_FN_PTR(verify_byte_codes_fn_new_t, verify_func);

       result = (*func)(env, cls, message, (int)message_len,

           klass->major_version());

     } else {

       verify_byte_codes_fn_t func =

         CAST_TO_FN_PTR(verify_byte_codes_fn_t, verify_func);

       result = (*func)(env, cls, message, (int)message_len);

     }

   }

   JNIHandles::destroy_local(cls);

   // These numbers are chosen so that VerifyClassCodes interface doesn't need

   // to be changed (still return jboolean (unsigned char)), and result is

   // 1 when verification is passed.

   if (result == 0) {

     return vmSymbols::java_lang_VerifyError();

   } else if (result == 1) {

     return NULL; // verified.

   } else if (result == 2) {

     THROW_MSG_(vmSymbols::java_lang_OutOfMemoryError(), message, NULL);

   } else if (result == 3) {

     return vmSymbols::java_lang_ClassFormatError();

   } else {

     ShouldNotReachHere();

     return NULL;

   }

 }

 TypeOrigin TypeOrigin::null() {

   return TypeOrigin();

 }

 TypeOrigin TypeOrigin::local(u2 index, StackMapFrame* frame) {

   assert(frame != NULL, "Must have a frame");

   return TypeOrigin(CF_LOCALS, index, StackMapFrame::copy(frame),

      frame->local_at(index));

 }

 TypeOrigin TypeOrigin::stack(u2 index, StackMapFrame* frame) {

   assert(frame != NULL, "Must have a frame");

   return TypeOrigin(CF_STACK, index, StackMapFrame::copy(frame),

       frame->stack_at(index));

 }

 TypeOrigin TypeOrigin::sm_local(u2 index, StackMapFrame* frame) {

   assert(frame != NULL, "Must have a frame");

   return TypeOrigin(SM_LOCALS, index, StackMapFrame::copy(frame),

       frame->local_at(index));

 }

 TypeOrigin TypeOrigin::sm_stack(u2 index, StackMapFrame* frame) {

   assert(frame != NULL, "Must have a frame");

   return TypeOrigin(SM_STACK, index, StackMapFrame::copy(frame),

       frame->stack_at(index));

 }

 TypeOrigin TypeOrigin::bad_index(u2 index) {

   return TypeOrigin(BAD_INDEX, index, NULL, VerificationType::bogus_type());

 }

 TypeOrigin TypeOrigin::cp(u2 index, VerificationType vt) {

   return TypeOrigin(CONST_POOL, index, NULL, vt);

 }

 TypeOrigin TypeOrigin::signature(VerificationType vt) {

   return TypeOrigin(SIG, 0, NULL, vt);

 }

 TypeOrigin TypeOrigin::implicit(VerificationType t) {

   return TypeOrigin(IMPLICIT, 0, NULL, t);

 }

 TypeOrigin TypeOrigin::frame(StackMapFrame* frame) {

   return TypeOrigin(FRAME_ONLY, 0, StackMapFrame::copy(frame),

                     VerificationType::bogus_type());

 }

 void TypeOrigin::reset_frame() {

   if (_frame != NULL) {

     _frame->restore();

   }

 }

 void TypeOrigin::details(outputStream* ss) const {

   _type.print_on(ss);

   switch (_origin) {

     case CF_LOCALS:

       ss->print(" (current frame, locals[%d])", _index);

       break;

     case CF_STACK:

       ss->print(" (current frame, stack[%d])", _index);

       break;

     case SM_LOCALS:

       ss->print(" (stack map, locals[%d])", _index);

       break;

     case SM_STACK:

       ss->print(" (stack map, stack[%d])", _index);

       break;

     case CONST_POOL:

       ss->print(" (constant pool %d)", _index);

       break;

     case SIG:

       ss->print(" (from method signature)");

       break;

     case IMPLICIT:

     case FRAME_ONLY:

     case NONE:

     default:

       ;

   }

 }

 #ifdef ASSERT

 void TypeOrigin::print_on(outputStream* str) const {

   str->print("{%d,%d,%p:", _origin, _index, _frame);

   if (_frame != NULL) {

     _frame->print_on(str);

   } else {

     str->print("null");

   }

   str->print(",");

   _type.print_on(str);

   str->print("}");

 }

 #endif

 void ErrorContext::details(outputStream* ss, const Method* method) const {

   if (is_valid()) {

     ss->cr();

     ss->print_cr("Exception Details:");

     location_details(ss, method);

     reason_details(ss);

     frame_details(ss);

     bytecode_details(ss, method);

     handler_details(ss, method);

     stackmap_details(ss, method);

   }

 }

 void ErrorContext::reason_details(outputStream* ss) const {

   streamIndentor si(ss);

   ss->indent().print_cr("Reason:");

   streamIndentor si2(ss);

   ss->indent().print("%s", "");

   switch (_fault) {

     case INVALID_BYTECODE:

       ss->print("Error exists in the bytecode");

       break;

     case WRONG_TYPE:

       if (_expected.is_valid()) {

         ss->print("Type ");

         _type.details(ss);

         ss->print(" is not assignable to ");

         _expected.details(ss);

       } else {

         ss->print("Invalid type: ");

         _type.details(ss);

       }

       break;

     case FLAGS_MISMATCH:

       if (_expected.is_valid()) {

         ss->print("Current frame's flags are not assignable "

                   "to stack map frame's.");

       } else {

         ss->print("Current frame's flags are invalid in this context.");

       }

       break;

     case BAD_CP_INDEX:

       ss->print("Constant pool index %d is invalid", _type.index());

       break;

     case BAD_LOCAL_INDEX:

       ss->print("Local index %d is invalid", _type.index());

       break;

     case LOCALS_SIZE_MISMATCH:

       ss->print("Current frame's local size doesn't match stackmap.");

       break;

     case STACK_SIZE_MISMATCH:

       ss->print("Current frame's stack size doesn't match stackmap.");

       break;

     case STACK_OVERFLOW:

       ss->print("Exceeded max stack size.");

       break;

     case STACK_UNDERFLOW:

       ss->print("Attempt to pop empty stack.");

       break;

     case MISSING_STACKMAP:

       ss->print("Expected stackmap frame at this location.");

       break;

     case BAD_STACKMAP:

       ss->print("Invalid stackmap specification.");

       break;

     case UNKNOWN:

     default:

       ShouldNotReachHere();

       ss->print_cr("Unknown");

   }

   ss->cr();

 }

 void ErrorContext::location_details(outputStream* ss, const Method* method) const {

   if (_bci != -1 && method != NULL) {

     streamIndentor si(ss);

     const char* bytecode_name = "<invalid>";

     if (method->validate_bci_from_bcx(_bci) != -1) {

       Bytecodes::Code code = Bytecodes::code_or_bp_at(method->bcp_from(_bci));

       if (Bytecodes::is_defined(code)) {

           bytecode_name = Bytecodes::name(code);

       } else {

           bytecode_name = "<illegal>";

       }

     }

     InstanceKlass* ik = method->method_holder();

     ss->indent().print_cr("Location:");

     streamIndentor si2(ss);

     ss->indent().print_cr("%s.%s%s @%d: %s",

         ik->name()->as_C_string(), method->name()->as_C_string(),

         method->signature()->as_C_string(), _bci, bytecode_name);

   }

 }

 void ErrorContext::frame_details(outputStream* ss) const {

   streamIndentor si(ss);

   if (_type.is_valid() && _type.frame() != NULL) {

     ss->indent().print_cr("Current Frame:");

     streamIndentor si2(ss);

     _type.frame()->print_on(ss);

   }

   if (_expected.is_valid() && _expected.frame() != NULL) {

     ss->indent().print_cr("Stackmap Frame:");

     streamIndentor si2(ss);

     _expected.frame()->print_on(ss);

   }

 }

 void ErrorContext::bytecode_details(outputStream* ss, const Method* method) const {

   if (method != NULL) {

     streamIndentor si(ss);

     ss->indent().print_cr("Bytecode:");

     streamIndentor si2(ss);

     ss->print_data(method->code_base(), method->code_size(), false);

   }

 }

 void ErrorContext::handler_details(outputStream* ss, const Method* method) const {

   if (method != NULL) {

     streamIndentor si(ss);

     ExceptionTable table(method);

     if (table.length() > 0) {

       ss->indent().print_cr("Exception Handler Table:");

       streamIndentor si2(ss);

       for (int i = 0; i < table.length(); ++i) {

         ss->indent().print_cr("bci [%d, %d] => handler: %d", table.start_pc(i),

             table.end_pc(i), table.handler_pc(i));

       }

     }

   }

 }

 void ErrorContext::stackmap_details(outputStream* ss, const Method* method) const {

   if (method != NULL && method->has_stackmap_table()) {

     streamIndentor si(ss);

     ss->indent().print_cr("Stackmap Table:");

     Array<u1>* data = method->stackmap_data();

     stack_map_table* sm_table =

         stack_map_table::at((address)data->adr_at(0));

     stack_map_frame* sm_frame = sm_table->entries();

     streamIndentor si2(ss);

     int current_offset = -1;

     address end_of_sm_table = (address)sm_table + method->stackmap_data()->length();

     for (u2 i = 0; i < sm_table->number_of_entries(); ++i) {

       ss->indent();

       if (!sm_frame->verify((address)sm_frame, end_of_sm_table)) {

         sm_frame->print_truncated(ss, current_offset);

         return;

       }

       sm_frame->print_on(ss, current_offset);

       ss->cr();

       current_offset += sm_frame->offset_delta();

       sm_frame = sm_frame->next();

     }

   }

 }

 // Methods in ClassVerifier

 ClassVerifier::ClassVerifier(

     instanceKlassHandle klass, TRAPS)

     : _thread(THREAD), _exception_type(NULL), _message(NULL), _klass(klass) {

   _this_type = VerificationType::reference_type(klass->name());

   // Create list to hold symbols in reference area.

   _symbols = new GrowableArray<Symbol*>(100, 0, NULL);

 }

 ClassVerifier::~ClassVerifier() {

   // Decrement the reference count for any symbols created.

   for (int i = 0; i < _symbols->length(); i++) {

     Symbol* s = _symbols->at(i);

     s->decrement_refcount();

   }

 }

 VerificationType ClassVerifier::object_type() const {

   return VerificationType::reference_type(vmSymbols::java_lang_Object());

 }

 TypeOrigin ClassVerifier::ref_ctx(const char* sig, TRAPS) {

   VerificationType vt = VerificationType::reference_type(

       create_temporary_symbol(sig, (int)strlen(sig), THREAD));

   return TypeOrigin::implicit(vt);

 }

 void ClassVerifier::verify_class(TRAPS) {

   if (VerboseVerification) {

     tty->print_cr("Verifying class %s with new format",

       _klass->external_name());

   }

   Array<Method*>* methods = _klass->methods();

   int num_methods = methods->length();

   for (int index = 0; index < num_methods; index++) {

     // Check for recursive re-verification before each method.

     if (was_recursively_verified())  return;

     Method* m = methods->at(index);

     if (m->is_native() || m->is_abstract() || m->is_overpass()) {

       // If m is native or abstract, skip it.  It is checked in class file

       // parser that methods do not override a final method.  Overpass methods

       // are trusted since the VM generates them.

       continue;

     }

     verify_method(methodHandle(THREAD, m), CHECK_VERIFY(this));

   }

   if (VerboseVerification || TraceClassInitialization) {

     if (was_recursively_verified())

       tty->print_cr("Recursive verification detected for: %s",

           _klass->external_name());

   }

 }

 void ClassVerifier::verify_method(methodHandle m, TRAPS) {

   HandleMark hm(THREAD);

   _method = m;   // initialize _method

   if (VerboseVerification) {

     tty->print_cr("Verifying method %s", m->name_and_sig_as_C_string());

   }

 // For clang, the only good constant format string is a literal constant format string.

 #define bad_type_msg "Bad type on operand stack in %s"

   int32_t max_stack = m->verifier_max_stack();

   int32_t max_locals = m->max_locals();

   constantPoolHandle cp(THREAD, m->constants());

   if (!SignatureVerifier::is_valid_method_signature(m->signature())) {

     class_format_error("Invalid method signature");

     return;

   }

   // Initial stack map frame: offset is 0, stack is initially empty.

   StackMapFrame current_frame(max_locals, max_stack, this);

   // Set initial locals

   VerificationType return_type = current_frame.set_locals_from_arg(

     m, current_type(), CHECK_VERIFY(this));

   int32_t stackmap_index = 0; // index to the stackmap array

   u4 code_length = m->code_size();

   // Scan the bytecode and map each instruction's start offset to a number.

   char* code_data = generate_code_data(m, code_length, CHECK_VERIFY(this));

   int ex_min = code_length;

   int ex_max = -1;

   // Look through each item on the exception table. Each of the fields must refer

   // to a legal instruction.

   verify_exception_handler_table(

     code_length, code_data, ex_min, ex_max, CHECK_VERIFY(this));

   // Look through each entry on the local variable table and make sure

   // its range of code array offsets is valid. (4169817)

   if (m->has_localvariable_table()) {

     verify_local_variable_table(code_length, code_data, CHECK_VERIFY(this));

   }

   Array<u1>* stackmap_data = m->stackmap_data();

   StackMapStream stream(stackmap_data);

   StackMapReader reader(this, &stream, code_data, code_length, THREAD);

   StackMapTable stackmap_table(&reader, &current_frame, max_locals, max_stack,

                                code_data, code_length, CHECK_VERIFY(this));

   if (VerboseVerification) {

     stackmap_table.print_on(tty);

   }

   RawBytecodeStream bcs(m);

   // Scan the byte code linearly from the start to the end

   bool no_control_flow = false; // Set to true when there is no direct control

                                 // flow from current instruction to the next

                                 // instruction in sequence

   Bytecodes::Code opcode;

   while (!bcs.is_last_bytecode()) {

     // Check for recursive re-verification before each bytecode.

     if (was_recursively_verified())  return;

     opcode = bcs.raw_next();

     u2 bci = bcs.bci();

     // Set current frame's offset to bci

     current_frame.set_offset(bci);

     current_frame.set_mark();

     // Make sure every offset in stackmap table point to the beginning to

     // an instruction. Match current_frame to stackmap_table entry with

     // the same offset if exists.

     stackmap_index = verify_stackmap_table(

       stackmap_index, bci, &current_frame, &stackmap_table,

       no_control_flow, CHECK_VERIFY(this));

     bool this_uninit = false;  // Set to true when invokespecial <init> initialized 'this'

     bool verified_exc_handlers = false;

     // Merge with the next instruction

     {

       u2 index;

       int target;

       VerificationType type, type2;

       VerificationType atype;

 #ifndef PRODUCT

       if (VerboseVerification) {

         current_frame.print_on(tty);

         tty->print_cr("offset = %d,  opcode = %s", bci, Bytecodes::name(opcode));

       }

 #endif

       // Make sure wide instruction is in correct format

       if (bcs.is_wide()) {

         if (opcode != Bytecodes::_iinc   && opcode != Bytecodes::_iload  &&

             opcode != Bytecodes::_aload  && opcode != Bytecodes::_lload  &&

             opcode != Bytecodes::_istore && opcode != Bytecodes::_astore &&

             opcode != Bytecodes::_lstore && opcode != Bytecodes::_fload  &&

             opcode != Bytecodes::_dload  && opcode != Bytecodes::_fstore &&

             opcode != Bytecodes::_dstore) {

           /* Unreachable?  RawBytecodeStream's raw_next() returns 'illegal'

            * if we encounter a wide instruction that modifies an invalid

            * opcode (not one of the ones listed above) */

           verify_error(ErrorContext::bad_code(bci), "Bad wide instruction");

           return;

         }

       }

       // Look for possible jump target in exception handlers and see if it

       // matches current_frame.  Do this check here for astore*, dstore*,

       // fstore*, istore*, and lstore* opcodes because they can change the type

       // state by adding a local.  JVM Spec says that the incoming type state

       // should be used for this check.  So, do the check here before a possible

       // local is added to the type state.

       if (Bytecodes::is_store_into_local(opcode) && bci >= ex_min && bci < ex_max) {

         verify_exception_handler_targets(

           bci, this_uninit, &current_frame, &stackmap_table, CHECK_VERIFY(this));

         verified_exc_handlers = true;

       }

       switch (opcode) {

         case Bytecodes::_nop :

           no_control_flow = false; break;

         case Bytecodes::_aconst_null :

           current_frame.push_stack(

             VerificationType::null_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_iconst_m1 :

         case Bytecodes::_iconst_0 :

         case Bytecodes::_iconst_1 :

         case Bytecodes::_iconst_2 :

         case Bytecodes::_iconst_3 :

         case Bytecodes::_iconst_4 :

         case Bytecodes::_iconst_5 :

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_lconst_0 :

         case Bytecodes::_lconst_1 :

           current_frame.push_stack_2(

             VerificationType::long_type(),

             VerificationType::long2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_fconst_0 :

         case Bytecodes::_fconst_1 :

         case Bytecodes::_fconst_2 :

           current_frame.push_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dconst_0 :

         case Bytecodes::_dconst_1 :

           current_frame.push_stack_2(

             VerificationType::double_type(),

             VerificationType::double2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_sipush :

         case Bytecodes::_bipush :

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_ldc :

           verify_ldc(

             opcode, bcs.get_index_u1(), &current_frame,

             cp, bci, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_ldc_w :

         case Bytecodes::_ldc2_w :

           verify_ldc(

             opcode, bcs.get_index_u2(), &current_frame,

             cp, bci, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_iload :

           verify_iload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_iload_0 :

         case Bytecodes::_iload_1 :

         case Bytecodes::_iload_2 :

         case Bytecodes::_iload_3 :

           index = opcode - Bytecodes::_iload_0;

           verify_iload(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_lload :

           verify_lload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_lload_0 :

         case Bytecodes::_lload_1 :

         case Bytecodes::_lload_2 :

         case Bytecodes::_lload_3 :

           index = opcode - Bytecodes::_lload_0;

           verify_lload(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_fload :

           verify_fload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_fload_0 :

         case Bytecodes::_fload_1 :

         case Bytecodes::_fload_2 :

         case Bytecodes::_fload_3 :

           index = opcode - Bytecodes::_fload_0;

           verify_fload(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dload :

           verify_dload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dload_0 :

         case Bytecodes::_dload_1 :

         case Bytecodes::_dload_2 :

         case Bytecodes::_dload_3 :

           index = opcode - Bytecodes::_dload_0;

           verify_dload(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_aload :

           verify_aload(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_aload_0 :

         case Bytecodes::_aload_1 :

         case Bytecodes::_aload_2 :

         case Bytecodes::_aload_3 :

           index = opcode - Bytecodes::_aload_0;

           verify_aload(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_iaload :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_int_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[I", THREAD)),

                 bad_type_msg, "iaload");

             return;

           }

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_baload :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_bool_array() && !atype.is_byte_array()) {

             verify_error(

                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "baload");

             return;

           }

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_caload :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_char_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[C", THREAD)),

                 bad_type_msg, "caload");

             return;

           }

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_saload :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_short_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[S", THREAD)),

                 bad_type_msg, "saload");

             return;

           }

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_laload :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_long_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[J", THREAD)),

                 bad_type_msg, "laload");

             return;

           }

           current_frame.push_stack_2(

             VerificationType::long_type(),

             VerificationType::long2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_faload :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_float_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[F", THREAD)),

                 bad_type_msg, "faload");

             return;

           }

           current_frame.push_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_daload :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_double_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[D", THREAD)),

                 bad_type_msg, "daload");

             return;

           }

           current_frame.push_stack_2(

             VerificationType::double_type(),

             VerificationType::double2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_aaload : {

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_reference_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(),

                 TypeOrigin::implicit(VerificationType::reference_check())),

                 bad_type_msg, "aaload");

             return;

           }

           if (atype.is_null()) {

             current_frame.push_stack(

               VerificationType::null_type(), CHECK_VERIFY(this));

           } else {

             VerificationType component =

               atype.get_component(this, CHECK_VERIFY(this));

             current_frame.push_stack(component, CHECK_VERIFY(this));

           }

           no_control_flow = false; break;

         }

         case Bytecodes::_istore :

           verify_istore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_istore_0 :

         case Bytecodes::_istore_1 :

         case Bytecodes::_istore_2 :

         case Bytecodes::_istore_3 :

           index = opcode - Bytecodes::_istore_0;

           verify_istore(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_lstore :

           verify_lstore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_lstore_0 :

         case Bytecodes::_lstore_1 :

         case Bytecodes::_lstore_2 :

         case Bytecodes::_lstore_3 :

           index = opcode - Bytecodes::_lstore_0;

           verify_lstore(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_fstore :

           verify_fstore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_fstore_0 :

         case Bytecodes::_fstore_1 :

         case Bytecodes::_fstore_2 :

         case Bytecodes::_fstore_3 :

           index = opcode - Bytecodes::_fstore_0;

           verify_fstore(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dstore :

           verify_dstore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dstore_0 :

         case Bytecodes::_dstore_1 :

         case Bytecodes::_dstore_2 :

         case Bytecodes::_dstore_3 :

           index = opcode - Bytecodes::_dstore_0;

           verify_dstore(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_astore :

           verify_astore(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_astore_0 :

         case Bytecodes::_astore_1 :

         case Bytecodes::_astore_2 :

         case Bytecodes::_astore_3 :

           index = opcode - Bytecodes::_astore_0;

           verify_astore(index, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_iastore :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           type2 = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_int_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[I", THREAD)),

                 bad_type_msg, "iastore");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_bastore :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           type2 = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_bool_array() && !atype.is_byte_array()) {

             verify_error(

                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "bastore");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_castore :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_char_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[C", THREAD)),

                 bad_type_msg, "castore");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_sastore :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_short_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[S", THREAD)),

                 bad_type_msg, "sastore");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_lastore :

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_long_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[J", THREAD)),

                 bad_type_msg, "lastore");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_fastore :

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           current_frame.pop_stack

             (VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_float_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[F", THREAD)),

                 bad_type_msg, "fastore");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_dastore :

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!atype.is_double_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(), ref_ctx("[D", THREAD)),

                 bad_type_msg, "dastore");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_aastore :

           type = current_frame.pop_stack(object_type(), CHECK_VERIFY(this));

           type2 = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           atype = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           // more type-checking is done at runtime

           if (!atype.is_reference_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 current_frame.stack_top_ctx(),

                 TypeOrigin::implicit(VerificationType::reference_check())),

                 bad_type_msg, "aastore");

             return;

           }

           // 4938384: relaxed constraint in JVMS 3nd edition.

           no_control_flow = false; break;

         case Bytecodes::_pop :

           current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_pop2 :

           type = current_frame.pop_stack(CHECK_VERIFY(this));

           if (type.is_category1()) {

             current_frame.pop_stack(

               VerificationType::category1_check(), CHECK_VERIFY(this));

           } else if (type.is_category2_2nd()) {

             current_frame.pop_stack(

               VerificationType::category2_check(), CHECK_VERIFY(this));

           } else {

             /* Unreachable? Would need a category2_1st on TOS

              * which does not appear possible. */

             verify_error(

                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "pop2");

             return;

           }

           no_control_flow = false; break;

         case Bytecodes::_dup :

           type = current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dup_x1 :

           type = current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           type2 = current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dup_x2 :

         {

           VerificationType type3;

           type = current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           type2 = current_frame.pop_stack(CHECK_VERIFY(this));

           if (type2.is_category1()) {

             type3 = current_frame.pop_stack(

               VerificationType::category1_check(), CHECK_VERIFY(this));

           } else if (type2.is_category2_2nd()) {

             type3 = current_frame.pop_stack(

               VerificationType::category2_check(), CHECK_VERIFY(this));

           } else {

             /* Unreachable? Would need a category2_1st at stack depth 2 with

              * a category1 on TOS which does not appear possible. */

             verify_error(ErrorContext::bad_type(

                 bci, current_frame.stack_top_ctx()), bad_type_msg, "dup_x2");

             return;

           }

           current_frame.push_stack(type, CHECK_VERIFY(this));

           current_frame.push_stack(type3, CHECK_VERIFY(this));

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         }

         case Bytecodes::_dup2 :

           type = current_frame.pop_stack(CHECK_VERIFY(this));

           if (type.is_category1()) {

             type2 = current_frame.pop_stack(

               VerificationType::category1_check(), CHECK_VERIFY(this));

           } else if (type.is_category2_2nd()) {

             type2 = current_frame.pop_stack(

               VerificationType::category2_check(), CHECK_VERIFY(this));

           } else {

             /* Unreachable?  Would need a category2_1st on TOS which does not

              * appear possible. */

             verify_error(

                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "dup2");

             return;

           }

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dup2_x1 :

         {

           VerificationType type3;

           type = current_frame.pop_stack(CHECK_VERIFY(this));

           if (type.is_category1()) {

             type2 = current_frame.pop_stack(

               VerificationType::category1_check(), CHECK_VERIFY(this));

           } else if (type.is_category2_2nd()) {

             type2 = current_frame.pop_stack(

               VerificationType::category2_check(), CHECK_VERIFY(this));

           } else {

             /* Unreachable?  Would need a category2_1st on TOS which does

              * not appear possible. */

             verify_error(

                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "dup2_x1");

             return;

           }

           type3 = current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           current_frame.push_stack(type3, CHECK_VERIFY(this));

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         }

         case Bytecodes::_dup2_x2 :

         {

           VerificationType type3, type4;

           type = current_frame.pop_stack(CHECK_VERIFY(this));

           if (type.is_category1()) {

             type2 = current_frame.pop_stack(

               VerificationType::category1_check(), CHECK_VERIFY(this));

           } else if (type.is_category2_2nd()) {

             type2 = current_frame.pop_stack(

               VerificationType::category2_check(), CHECK_VERIFY(this));

           } else {

             /* Unreachable?  Would need a category2_1st on TOS which does

              * not appear possible. */

             verify_error(

                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "dup2_x2");

             return;

           }

           type3 = current_frame.pop_stack(CHECK_VERIFY(this));

           if (type3.is_category1()) {

             type4 = current_frame.pop_stack(

               VerificationType::category1_check(), CHECK_VERIFY(this));

           } else if (type3.is_category2_2nd()) {

             type4 = current_frame.pop_stack(

               VerificationType::category2_check(), CHECK_VERIFY(this));

           } else {

             /* Unreachable?  Would need a category2_1st on TOS after popping

              * a long/double or two category 1's, which does not

              * appear possible. */

             verify_error(

                 ErrorContext::bad_type(bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "dup2_x2");

             return;

           }

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           current_frame.push_stack(type4, CHECK_VERIFY(this));

           current_frame.push_stack(type3, CHECK_VERIFY(this));

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         }

         case Bytecodes::_swap :

           type = current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           type2 = current_frame.pop_stack(

             VerificationType::category1_check(), CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           current_frame.push_stack(type2, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_iadd :

         case Bytecodes::_isub :

         case Bytecodes::_imul :

         case Bytecodes::_idiv :

         case Bytecodes::_irem :

         case Bytecodes::_ishl :

         case Bytecodes::_ishr :

         case Bytecodes::_iushr :

         case Bytecodes::_ior :

         case Bytecodes::_ixor :

         case Bytecodes::_iand :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           // fall through

         case Bytecodes::_ineg :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_ladd :

         case Bytecodes::_lsub :

         case Bytecodes::_lmul :

         case Bytecodes::_ldiv :

         case Bytecodes::_lrem :

         case Bytecodes::_land :

         case Bytecodes::_lor :

         case Bytecodes::_lxor :

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           // fall through

         case Bytecodes::_lneg :

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::long_type(),

             VerificationType::long2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_lshl :

         case Bytecodes::_lshr :

         case Bytecodes::_lushr :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::long_type(),

             VerificationType::long2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_fadd :

         case Bytecodes::_fsub :

         case Bytecodes::_fmul :

         case Bytecodes::_fdiv :

         case Bytecodes::_frem :

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           // fall through

         case Bytecodes::_fneg :

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dadd :

         case Bytecodes::_dsub :

         case Bytecodes::_dmul :

         case Bytecodes::_ddiv :

         case Bytecodes::_drem :

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           // fall through

         case Bytecodes::_dneg :

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::double_type(),

             VerificationType::double2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_iinc :

           verify_iinc(bcs.get_index(), &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_i2l :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::long_type(),

             VerificationType::long2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

        case Bytecodes::_l2i :

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_i2f :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_i2d :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::double_type(),

             VerificationType::double2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_l2f :

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_l2d :

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::double_type(),

             VerificationType::double2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_f2i :

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_f2l :

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::long_type(),

             VerificationType::long2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_f2d :

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::double_type(),

             VerificationType::double2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_d2i :

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_d2l :

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           current_frame.push_stack_2(

             VerificationType::long_type(),

             VerificationType::long2_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_d2f :

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_i2b :

         case Bytecodes::_i2c :

         case Bytecodes::_i2s :

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_lcmp :

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.pop_stack_2(

             VerificationType::long2_type(),

             VerificationType::long_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_fcmpl :

         case Bytecodes::_fcmpg :

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_dcmpl :

         case Bytecodes::_dcmpg :

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           current_frame.pop_stack_2(

             VerificationType::double2_type(),

             VerificationType::double_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_if_icmpeq:

         case Bytecodes::_if_icmpne:

         case Bytecodes::_if_icmplt:

         case Bytecodes::_if_icmpge:

         case Bytecodes::_if_icmpgt:

         case Bytecodes::_if_icmple:

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           // fall through

         case Bytecodes::_ifeq:

         case Bytecodes::_ifne:

         case Bytecodes::_iflt:

         case Bytecodes::_ifge:

         case Bytecodes::_ifgt:

         case Bytecodes::_ifle:

           current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           target = bcs.dest();

           stackmap_table.check_jump_target(

             &current_frame, target, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_if_acmpeq :

         case Bytecodes::_if_acmpne :

           current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           // fall through

         case Bytecodes::_ifnull :

         case Bytecodes::_ifnonnull :

           current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           target = bcs.dest();

           stackmap_table.check_jump_target

             (&current_frame, target, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_goto :

           target = bcs.dest();

           stackmap_table.check_jump_target(

             &current_frame, target, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_goto_w :

           target = bcs.dest_w();

           stackmap_table.check_jump_target(

             &current_frame, target, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_tableswitch :

         case Bytecodes::_lookupswitch :

           verify_switch(

             &bcs, code_length, code_data, &current_frame,

             &stackmap_table, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_ireturn :

           type = current_frame.pop_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           verify_return_value(return_type, type, bci,

                               &current_frame, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_lreturn :

           type2 = current_frame.pop_stack(

             VerificationType::long2_type(), CHECK_VERIFY(this));

           type = current_frame.pop_stack(

             VerificationType::long_type(), CHECK_VERIFY(this));

           verify_return_value(return_type, type, bci,

                               &current_frame, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_freturn :

           type = current_frame.pop_stack(

             VerificationType::float_type(), CHECK_VERIFY(this));

           verify_return_value(return_type, type, bci,

                               &current_frame, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_dreturn :

           type2 = current_frame.pop_stack(

             VerificationType::double2_type(),  CHECK_VERIFY(this));

           type = current_frame.pop_stack(

             VerificationType::double_type(), CHECK_VERIFY(this));

           verify_return_value(return_type, type, bci,

                               &current_frame, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_areturn :

           type = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           verify_return_value(return_type, type, bci,

                               &current_frame, CHECK_VERIFY(this));

           no_control_flow = true; break;

         case Bytecodes::_return :

           if (return_type != VerificationType::bogus_type()) {

             verify_error(ErrorContext::bad_code(bci),

                          "Method expects a return value");

             return;

           }

           // Make sure "this" has been initialized if current method is an

           // <init>

           if (_method->name() == vmSymbols::object_initializer_name() &&

               current_frame.flag_this_uninit()) {

             verify_error(ErrorContext::bad_code(bci),

                          "Constructor must call super() or this() "

                          "before return");

             return;

           }

           no_control_flow = true; break;

         case Bytecodes::_getstatic :

         case Bytecodes::_putstatic :

         case Bytecodes::_getfield :

         case Bytecodes::_putfield :

           verify_field_instructions(

             &bcs, &current_frame, cp, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_invokevirtual :

         case Bytecodes::_invokespecial :

         case Bytecodes::_invokestatic :

           verify_invoke_instructions(

             &bcs, code_length, &current_frame, (bci >= ex_min && bci < ex_max),

             &this_uninit, return_type, cp, &stackmap_table, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_invokeinterface :

         case Bytecodes::_invokedynamic :

           verify_invoke_instructions(

             &bcs, code_length, &current_frame, (bci >= ex_min && bci < ex_max),

             &this_uninit, return_type, cp, &stackmap_table, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_new :

         {

           index = bcs.get_index_u2();

           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));

           VerificationType new_class_type =

             cp_index_to_type(index, cp, CHECK_VERIFY(this));

           if (!new_class_type.is_object()) {

             verify_error(ErrorContext::bad_type(bci,

                 TypeOrigin::cp(index, new_class_type)),

                 "Illegal new instruction");

             return;

           }

           type = VerificationType::uninitialized_type(bci);

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         }

         case Bytecodes::_newarray :

           type = get_newarray_type(bcs.get_index(), bci, CHECK_VERIFY(this));

           current_frame.pop_stack(

             VerificationType::integer_type(),  CHECK_VERIFY(this));

           current_frame.push_stack(type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_anewarray :

           verify_anewarray(

             bci, bcs.get_index_u2(), cp, &current_frame, CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_arraylength :

           type = current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           if (!(type.is_null() || type.is_array())) {

             verify_error(ErrorContext::bad_type(

                 bci, current_frame.stack_top_ctx()),

                 bad_type_msg, "arraylength");

           }

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_checkcast :

         {

           index = bcs.get_index_u2();

           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));

           current_frame.pop_stack(object_type(), CHECK_VERIFY(this));

           VerificationType klass_type = cp_index_to_type(

             index, cp, CHECK_VERIFY(this));

           current_frame.push_stack(klass_type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         }

         case Bytecodes::_instanceof : {

           index = bcs.get_index_u2();

           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));

           current_frame.pop_stack(object_type(), CHECK_VERIFY(this));

           current_frame.push_stack(

             VerificationType::integer_type(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         }

         case Bytecodes::_monitorenter :

         case Bytecodes::_monitorexit :

           current_frame.pop_stack(

             VerificationType::reference_check(), CHECK_VERIFY(this));

           no_control_flow = false; break;

         case Bytecodes::_multianewarray :

         {

           index = bcs.get_index_u2();

           u2 dim = *(bcs.bcp()+3);

           verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));

           VerificationType new_array_type =

             cp_index_to_type(index, cp, CHECK_VERIFY(this));

           if (!new_array_type.is_array()) {

             verify_error(ErrorContext::bad_type(bci,

                 TypeOrigin::cp(index, new_array_type)),

                 "Illegal constant pool index in multianewarray instruction");

             return;

           }

           if (dim < 1 || new_array_type.dimensions() < dim) {

             verify_error(ErrorContext::bad_code(bci),

                 "Illegal dimension in multianewarray instruction: %d", dim);

             return;

           }

           for (int i = 0; i < dim; i++) {

             current_frame.pop_stack(

               VerificationType::integer_type(), CHECK_VERIFY(this));

           }

           current_frame.push_stack(new_array_type, CHECK_VERIFY(this));

           no_control_flow = false; break;

         }

         case Bytecodes::_athrow :

           type = VerificationType::reference_type(

             vmSymbols::java_lang_Throwable());

           current_frame.pop_stack(type, CHECK_VERIFY(this));

           no_control_flow = true; break;

         default:

           // We only need to check the valid bytecodes in class file.

           // And jsr and ret are not in the new class file format in JDK1.5.

           verify_error(ErrorContext::bad_code(bci),

               "Bad instruction: %02x", opcode);

           no_control_flow = false;

           return;

       }  // end switch

     }  // end Merge with the next instruction

     // Look for possible jump target in exception handlers and see if it matches

     // current_frame.  Don't do this check if it has already been done (for

     // ([a,d,f,i,l]store* opcodes).  This check cannot be done earlier because

     // opcodes, such as invokespecial, may set the this_uninit flag.

     assert(!(verified_exc_handlers && this_uninit),

       "Exception handler targets got verified before this_uninit got set");

     if (!verified_exc_handlers && bci >= ex_min && bci < ex_max) {

       verify_exception_handler_targets(

         bci, this_uninit, &current_frame, &stackmap_table, CHECK_VERIFY(this));

     }

   } // end while

   // Make sure that control flow does not fall through end of the method

   if (!no_control_flow) {

     verify_error(ErrorContext::bad_code(code_length),

         "Control flow falls through code end");

     return;

   }

 }

 #undef bad_type_message

 char* ClassVerifier::generate_code_data(methodHandle m, u4 code_length, TRAPS) {

   char* code_data = NEW_RESOURCE_ARRAY(char, code_length);

   memset(code_data, 0, sizeof(char) * code_length);

   RawBytecodeStream bcs(m);

   while (!bcs.is_last_bytecode()) {

     if (bcs.raw_next() != Bytecodes::_illegal) {

       int bci = bcs.bci();

       if (bcs.raw_code() == Bytecodes::_new) {

         code_data[bci] = NEW_OFFSET;

       } else {

         code_data[bci] = BYTECODE_OFFSET;

       }

     } else {

       verify_error(ErrorContext::bad_code(bcs.bci()), "Bad instruction");

       return NULL;

     }

   }

   return code_data;

 }

 void ClassVerifier::verify_exception_handler_table(u4 code_length, char* code_data, int& min, int& max, TRAPS) {

   ExceptionTable exhandlers(_method());

   int exlength = exhandlers.length();

   constantPoolHandle cp (THREAD, _method->constants());

   for(int i = 0; i < exlength; i++) {

     //reacquire the table in case a GC happened

     ExceptionTable exhandlers(_method());

     u2 start_pc = exhandlers.start_pc(i);

     u2 end_pc = exhandlers.end_pc(i);

     u2 handler_pc = exhandlers.handler_pc(i);

     if (start_pc >= code_length || code_data[start_pc] == 0) {

       class_format_error("Illegal exception table start_pc %d", start_pc);

       return;

     }

     if (end_pc != code_length) {   // special case: end_pc == code_length

       if (end_pc > code_length || code_data[end_pc] == 0) {

         class_format_error("Illegal exception table end_pc %d", end_pc);

         return;

       }

     }

     if (handler_pc >= code_length || code_data[handler_pc] == 0) {

       class_format_error("Illegal exception table handler_pc %d", handler_pc);

       return;

     }

     int catch_type_index = exhandlers.catch_type_index(i);

     if (catch_type_index != 0) {

       VerificationType catch_type = cp_index_to_type(

         catch_type_index, cp, CHECK_VERIFY(this));

       VerificationType throwable =

         VerificationType::reference_type(vmSymbols::java_lang_Throwable());

       bool is_subclass = throwable.is_assignable_from(

         catch_type, this, false, CHECK_VERIFY(this));

       if (!is_subclass) {

         // 4286534: should throw VerifyError according to recent spec change

         verify_error(ErrorContext::bad_type(handler_pc,

             TypeOrigin::cp(catch_type_index, catch_type),

             TypeOrigin::implicit(throwable)),

             "Catch type is not a subclass "

             "of Throwable in exception handler %d", handler_pc);

         return;

       }

     }

     if (start_pc < min) min = start_pc;

     if (end_pc > max) max = end_pc;

   }

 }

 void ClassVerifier::verify_local_variable_table(u4 code_length, char* code_data, TRAPS) {

   int localvariable_table_length = _method()->localvariable_table_length();

   if (localvariable_table_length > 0) {

     LocalVariableTableElement* table = _method()->localvariable_table_start();

     for (int i = 0; i < localvariable_table_length; i++) {

       u2 start_bci = table[i].start_bci;

       u2 length = table[i].length;

       if (start_bci >= code_length || code_data[start_bci] == 0) {

         class_format_error(

           "Illegal local variable table start_pc %d", start_bci);

         return;

       }

       u4 end_bci = (u4)(start_bci + length);

       if (end_bci != code_length) {

         if (end_bci >= code_length || code_data[end_bci] == 0) {

           class_format_error( "Illegal local variable table length %d", length);

           return;

         }

       }

     }

   }

 }

 u2 ClassVerifier::verify_stackmap_table(u2 stackmap_index, u2 bci,

                                         StackMapFrame* current_frame,

                                         StackMapTable* stackmap_table,

                                         bool no_control_flow, TRAPS) {

   if (stackmap_index < stackmap_table->get_frame_count()) {

     u2 this_offset = stackmap_table->get_offset(stackmap_index);

     if (no_control_flow && this_offset > bci) {

       verify_error(ErrorContext::missing_stackmap(bci),

                    "Expecting a stack map frame");

       return 0;

     }

     if (this_offset == bci) {

       ErrorContext ctx;

       // See if current stack map can be assigned to the frame in table.

       // current_frame is the stackmap frame got from the last instruction.

       // If matched, current_frame will be updated by this method.

       bool matches = stackmap_table->match_stackmap(

         current_frame, this_offset, stackmap_index,

         !no_control_flow, true, &ctx, CHECK_VERIFY_(this, 0));

       if (!matches) {

         // report type error

         verify_error(ctx, "Instruction type does not match stack map");

         return 0;

       }

       stackmap_index++;

     } else if (this_offset < bci) {

       // current_offset should have met this_offset.

       class_format_error("Bad stack map offset %d", this_offset);

       return 0;

     }

   } else if (no_control_flow) {

     verify_error(ErrorContext::bad_code(bci), "Expecting a stack map frame");

     return 0;

   }

   return stackmap_index;

 }

 void ClassVerifier::verify_exception_handler_targets(u2 bci, bool this_uninit, StackMapFrame* current_frame,

                                                      StackMapTable* stackmap_table, TRAPS) {

   constantPoolHandle cp (THREAD, _method->constants());

   ExceptionTable exhandlers(_method());

   int exlength = exhandlers.length();

   for(int i = 0; i < exlength; i++) {

     //reacquire the table in case a GC happened

     ExceptionTable exhandlers(_method());

     u2 start_pc = exhandlers.start_pc(i);

     u2 end_pc = exhandlers.end_pc(i);

     u2 handler_pc = exhandlers.handler_pc(i);

     int catch_type_index = exhandlers.catch_type_index(i);

     if(bci >= start_pc && bci < end_pc) {

       u1 flags = current_frame->flags();

       if (this_uninit) {  flags |= FLAG_THIS_UNINIT; }

       StackMapFrame* new_frame = current_frame->frame_in_exception_handler(flags);

       if (catch_type_index != 0) {

         // We know that this index refers to a subclass of Throwable

         VerificationType catch_type = cp_index_to_type(

           catch_type_index, cp, CHECK_VERIFY(this));

         new_frame->push_stack(catch_type, CHECK_VERIFY(this));

       } else {

         VerificationType throwable =

           VerificationType::reference_type(vmSymbols::java_lang_Throwable());

         new_frame->push_stack(throwable, CHECK_VERIFY(this));

       }

       ErrorContext ctx;

       bool matches = stackmap_table->match_stackmap(

         new_frame, handler_pc, true, false, &ctx, CHECK_VERIFY(this));

       if (!matches) {

         verify_error(ctx, "Stack map does not match the one at "

             "exception handler %d", handler_pc);

         return;

       }

     }

   }

 }

 void ClassVerifier::verify_cp_index(

     u2 bci, constantPoolHandle cp, int index, TRAPS) {

   int nconstants = cp->length();

   if ((index <= 0) || (index >= nconstants)) {

     verify_error(ErrorContext::bad_cp_index(bci, index),

         "Illegal constant pool index %d in class %s",

         index, cp->pool_holder()->external_name());

     return;

   }

 }

 void ClassVerifier::verify_cp_type(

     u2 bci, int index, constantPoolHandle cp, unsigned int types, TRAPS) {

   // In some situations, bytecode rewriting may occur while we're verifying.

   // In this case, a constant pool cache exists and some indices refer to that

   // instead.  Be sure we don't pick up such indices by accident.

   // We must check was_recursively_verified() before we get here.

   guarantee(cp->cache() == NULL, "not rewritten yet");

   verify_cp_index(bci, cp, index, CHECK_VERIFY(this));

   unsigned int tag = cp->tag_at(index).value();

   if ((types & (1 << tag)) == 0) {

     verify_error(ErrorContext::bad_cp_index(bci, index),

       "Illegal type at constant pool entry %d in class %s",

       index, cp->pool_holder()->external_name());

     return;

   }

 }

 void ClassVerifier::verify_cp_class_type(

     u2 bci, int index, constantPoolHandle cp, TRAPS) {

   verify_cp_index(bci, cp, index, CHECK_VERIFY(this));

   constantTag tag = cp->tag_at(index);

   if (!tag.is_klass() && !tag.is_unresolved_klass()) {

     verify_error(ErrorContext::bad_cp_index(bci, index),

         "Illegal type at constant pool entry %d in class %s",

         index, cp->pool_holder()->external_name());

     return;

   }

 }

 void ClassVerifier::verify_error(ErrorContext ctx, const char* msg, ...) {

   stringStream ss;

   ctx.reset_frames();

   _exception_type = vmSymbols::java_lang_VerifyError();

   _error_context = ctx;

   va_list va;

   va_start(va, msg);

   ss.vprint(msg, va);

   va_end(va);

   _message = ss.as_string();

 #ifdef ASSERT

   ResourceMark rm;

   const char* exception_name = _exception_type->as_C_string();

   Exceptions::debug_check_abort(exception_name, NULL);

 #endif // ndef ASSERT

 }

 void ClassVerifier::class_format_error(const char* msg, ...) {

   stringStream ss;

   _exception_type = vmSymbols::java_lang_ClassFormatError();

   va_list va;

   va_start(va, msg);

   ss.vprint(msg, va);

   va_end(va);

   if (!_method.is_null()) {

     ss.print(" in method %s", _method->name_and_sig_as_C_string());

   }

   _message = ss.as_string();

 }

 Klass* ClassVerifier::load_class(Symbol* name, TRAPS) {

   // Get current loader and protection domain first.

   oop loader = current_class()->class_loader();

   oop protection_domain = current_class()->protection_domain();

   return SystemDictionary::resolve_or_fail(

     name, Handle(THREAD, loader), Handle(THREAD, protection_domain),

     true, CHECK_NULL);

 }

 bool ClassVerifier::is_protected_access(instanceKlassHandle this_class,

                                         Klass* target_class,

                                         Symbol* field_name,

                                         Symbol* field_sig,

                                         bool is_method) {

   No_Safepoint_Verifier nosafepoint;

   // If target class isn't a super class of this class, we don't worry about this case

   if (!this_class->is_subclass_of(target_class)) {

     return false;

   }

   // Check if the specified method or field is protected

   InstanceKlass* target_instance = InstanceKlass::cast(target_class);

   fieldDescriptor fd;

   if (is_method) {

     Method* m = target_instance->uncached_lookup_method(field_name, field_sig, Klass::find_overpass);

     if (m != NULL && m->is_protected()) {

       if (!this_class->is_same_class_package(m->method_holder())) {

         return true;

       }

     }

   } else {

     Klass* member_klass = target_instance->find_field(field_name, field_sig, &fd);

     if (member_klass != NULL && fd.is_protected()) {

       if (!this_class->is_same_class_package(member_klass)) {

         return true;

       }

     }

   }

   return false;

 }

 void ClassVerifier::verify_ldc(

     int opcode, u2 index, StackMapFrame* current_frame,

     constantPoolHandle cp, u2 bci, TRAPS) {

   verify_cp_index(bci, cp, index, CHECK_VERIFY(this));

   constantTag tag = cp->tag_at(index);

   unsigned int types;

   if (opcode == Bytecodes::_ldc || opcode == Bytecodes::_ldc_w) {

     if (!tag.is_unresolved_klass()) {

       types = (1 << JVM_CONSTANT_Integer) | (1 << JVM_CONSTANT_Float)

             | (1 << JVM_CONSTANT_String)  | (1 << JVM_CONSTANT_Class)

             | (1 << JVM_CONSTANT_MethodHandle) | (1 << JVM_CONSTANT_MethodType);

       // Note:  The class file parser already verified the legality of

       // MethodHandle and MethodType constants.

       verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));

     }

   } else {

     assert(opcode == Bytecodes::_ldc2_w, "must be ldc2_w");

     types = (1 << JVM_CONSTANT_Double) | (1 << JVM_CONSTANT_Long);

     verify_cp_type(bci, index, cp, types, CHECK_VERIFY(this));

   }

   if (tag.is_string() && cp->is_pseudo_string_at(index)) {

     current_frame->push_stack(object_type(), CHECK_VERIFY(this));

   } else if (tag.is_string()) {

     current_frame->push_stack(

       VerificationType::reference_type(

         vmSymbols::java_lang_String()), CHECK_VERIFY(this));

   } else if (tag.is_klass() || tag.is_unresolved_klass()) {

     current_frame->push_stack(

       VerificationType::reference_type(

         vmSymbols::java_lang_Class()), CHECK_VERIFY(this));

   } else if (tag.is_int()) {

     current_frame->push_stack(

       VerificationType::integer_type(), CHECK_VERIFY(this));

   } else if (tag.is_float()) {

     current_frame->push_stack(

       VerificationType::float_type(), CHECK_VERIFY(this));

   } else if (tag.is_double()) {

     current_frame->push_stack_2(

       VerificationType::double_type(),

       VerificationType::double2_type(), CHECK_VERIFY(this));

   } else if (tag.is_long()) {

     current_frame->push_stack_2(

       VerificationType::long_type(),

       VerificationType::long2_type(), CHECK_VERIFY(this));

   } else if (tag.is_method_handle()) {

     current_frame->push_stack(

       VerificationType::reference_type(

         vmSymbols::java_lang_invoke_MethodHandle()), CHECK_VERIFY(this));

   } else if (tag.is_method_type()) {

     current_frame->push_stack(

       VerificationType::reference_type(

         vmSymbols::java_lang_invoke_MethodType()), CHECK_VERIFY(this));

   } else {

     /* Unreachable? verify_cp_type has already validated the cp type. */

     verify_error(

         ErrorContext::bad_cp_index(bci, index), "Invalid index in ldc");

     return;

   }

 }

 void ClassVerifier::verify_switch(

     RawBytecodeStream* bcs, u4 code_length, char* code_data,

     StackMapFrame* current_frame, StackMapTable* stackmap_table, TRAPS) {

   int bci = bcs->bci();

   address bcp = bcs->bcp();

   address aligned_bcp = (address) round_to((intptr_t)(bcp + 1), jintSize);

   if (_klass->major_version() < NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION) {

     // 4639449 & 4647081: padding bytes must be 0

     u2 padding_offset = 1;

     while ((bcp + padding_offset) < aligned_bcp) {

       if(*(bcp + padding_offset) != 0) {

         verify_error(ErrorContext::bad_code(bci),

                      "Nonzero padding byte in lookswitch or tableswitch");

         return;

       }

       padding_offset++;

     }

   }

   int default_offset = (int) Bytes::get_Java_u4(aligned_bcp);

   int keys, delta;

   current_frame->pop_stack(

     VerificationType::integer_type(), CHECK_VERIFY(this));

   if (bcs->raw_code() == Bytecodes::_tableswitch) {

     jint low = (jint)Bytes::get_Java_u4(aligned_bcp + jintSize);

     jint high = (jint)Bytes::get_Java_u4(aligned_bcp + 2*jintSize);

     if (low > high) {

       verify_error(ErrorContext::bad_code(bci),

           "low must be less than or equal to high in tableswitch");

       return;

     }

     keys = high - low + 1;

     if (keys < 0) {

       verify_error(ErrorContext::bad_code(bci), "too many keys in tableswitch");

       return;

     }

     delta = 1;

   } else {

     keys = (int)Bytes::get_Java_u4(aligned_bcp + jintSize);

     if (keys < 0) {

       verify_error(ErrorContext::bad_code(bci),

                    "number of keys in lookupswitch less than 0");

       return;

     }

     delta = 2;

     // Make sure that the lookupswitch items are sorted

     for (int i = 0; i < (keys - 1); i++) {

       jint this_key = Bytes::get_Java_u4(aligned_bcp + (2+2*i)*jintSize);

       jint next_key = Bytes::get_Java_u4(aligned_bcp + (2+2*i+2)*jintSize);

       if (this_key >= next_key) {

         verify_error(ErrorContext::bad_code(bci),

                      "Bad lookupswitch instruction");

         return;

       }

     }

   }

   int target = bci + default_offset;

   stackmap_table->check_jump_target(current_frame, target, CHECK_VERIFY(this));

   for (int i = 0; i < keys; i++) {

     // Because check_jump_target() may safepoint, the bytecode could have

     // moved, which means 'aligned_bcp' is no good and needs to be recalculated.

     aligned_bcp = (address)round_to((intptr_t)(bcs->bcp() + 1), jintSize);

     target = bci + (jint)Bytes::get_Java_u4(aligned_bcp+(3+i*delta)*jintSize);

     stackmap_table->check_jump_target(

       current_frame, target, CHECK_VERIFY(this));

   }

   NOT_PRODUCT(aligned_bcp = NULL);  // no longer valid at this point

 }

 bool ClassVerifier::name_in_supers(

     Symbol* ref_name, instanceKlassHandle current) {

   Klass* super = current->super();

   while (super != NULL) {

     if (super->name() == ref_name) {

       return true;

     }

     super = super->super();

   }

   return false;

 }

 void ClassVerifier::verify_field_instructions(RawBytecodeStream* bcs,

                                               StackMapFrame* current_frame,

                                               constantPoolHandle cp,

                                               TRAPS) {

   u2 index = bcs->get_index_u2();

   verify_cp_type(bcs->bci(), index, cp,

       1 << JVM_CONSTANT_Fieldref, CHECK_VERIFY(this));

   // Get field name and signature

   Symbol* field_name = cp->name_ref_at(index);

   Symbol* field_sig = cp->signature_ref_at(index);

   if (!SignatureVerifier::is_valid_type_signature(field_sig)) {

     class_format_error(

       "Invalid signature for field in class %s referenced "

       "from constant pool index %d", _klass->external_name(), index);

     return;

   }

   // Get referenced class type

   VerificationType ref_class_type = cp_ref_index_to_type(

     index, cp, CHECK_VERIFY(this));

   if (!ref_class_type.is_object()) {

     /* Unreachable?  Class file parser verifies Fieldref contents */

     verify_error(ErrorContext::bad_type(bcs->bci(),

         TypeOrigin::cp(index, ref_class_type)),

         "Expecting reference to class in class %s at constant pool index %d",

         _klass->external_name(), index);

     return;

   }

   VerificationType target_class_type = ref_class_type;

   assert(sizeof(VerificationType) == sizeof(uintptr_t),

         "buffer type must match VerificationType size");

   uintptr_t field_type_buffer[2];

   VerificationType* field_type = (VerificationType*)field_type_buffer;

   // If we make a VerificationType[2] array directly, the compiler calls

   // to the c-runtime library to do the allocation instead of just

   // stack allocating it.  Plus it would run constructors.  This shows up

   // in performance profiles.

   SignatureStream sig_stream(field_sig, false);

   VerificationType stack_object_type;

   int n = change_sig_to_verificationType(

     &sig_stream, field_type, CHECK_VERIFY(this));

   u2 bci = bcs->bci();

   bool is_assignable;

   switch (bcs->raw_code()) {

     case Bytecodes::_getstatic: {

       for (int i = 0; i < n; i++) {

         current_frame->push_stack(field_type[i], CHECK_VERIFY(this));

       }

       break;

     }

     case Bytecodes::_putstatic: {

       for (int i = n - 1; i >= 0; i--) {

         current_frame->pop_stack(field_type[i], CHECK_VERIFY(this));

       }

       break;

     }

     case Bytecodes::_getfield: {

       stack_object_type = current_frame->pop_stack(

         target_class_type, CHECK_VERIFY(this));

       for (int i = 0; i < n; i++) {

         current_frame->push_stack(field_type[i], CHECK_VERIFY(this));

       }

       goto check_protected;

     }

     case Bytecodes::_putfield: {

       for (int i = n - 1; i >= 0; i--) {

         current_frame->pop_stack(field_type[i], CHECK_VERIFY(this));

       }

       stack_object_type = current_frame->pop_stack(CHECK_VERIFY(this));

       // The JVMS 2nd edition allows field initialization before the superclass

       // initializer, if the field is defined within the current class.

       fieldDescriptor fd;

       if (stack_object_type == VerificationType::uninitialized_this_type() &&

           target_class_type.equals(current_type()) &&

           _klass->find_local_field(field_name, field_sig, &fd)) {

         stack_object_type = current_type();

       }

       is_assignable = target_class_type.is_assignable_from(

         stack_object_type, this, false, CHECK_VERIFY(this));

       if (!is_assignable) {

         verify_error(ErrorContext::bad_type(bci,

             current_frame->stack_top_ctx(),

             TypeOrigin::cp(index, target_class_type)),

             "Bad type on operand stack in putfield");

         return;

       }

     }

     check_protected: {

       if (_this_type == stack_object_type)

         break; // stack_object_type must be assignable to _current_class_type

       Symbol* ref_class_name =

         cp->klass_name_at(cp->klass_ref_index_at(index));

       if (!name_in_supers(ref_class_name, current_class()))

         // stack_object_type must be assignable to _current_class_type since:

         // 1. stack_object_type must be assignable to ref_class.

         // 2. ref_class must be _current_class or a subclass of it. It can't

         //    be a superclass of it. See revised JVMS 5.4.4.

         break;

       Klass* ref_class_oop = load_class(ref_class_name, CHECK);

       if (is_protected_access(current_class(), ref_class_oop, field_name,

                               field_sig, false)) {

         // It's protected access, check if stack object is assignable to

         // current class.

         is_assignable = current_type().is_assignable_from(

           stack_object_type, this, true, CHECK_VERIFY(this));

         if (!is_assignable) {

           verify_error(ErrorContext::bad_type(bci,

               current_frame->stack_top_ctx(),

               TypeOrigin::implicit(current_type())),

               "Bad access to protected data in getfield");

           return;

         }

       }

       break;

     }

     default: ShouldNotReachHere();

   }

 }

 // Look at the method's handlers.  If the bci is in the handler's try block

 // then check if the handler_pc is already on the stack.  If not, push it

 // unless the handler has already been scanned.

 void ClassVerifier::push_handlers(ExceptionTable* exhandlers,

                                   GrowableArray<u4>* handler_list,

                                   GrowableArray<u4>* handler_stack,

                                   u4 bci) {

   int exlength = exhandlers->length();

   for(int x = 0; x < exlength; x++) {

     if (bci >= exhandlers->start_pc(x) && bci < exhandlers->end_pc(x)) {

       u4 exhandler_pc = exhandlers->handler_pc(x);

       if (!handler_list->contains(exhandler_pc)) {

         handler_stack->append_if_missing(exhandler_pc);

         handler_list->append(exhandler_pc);

       }

     }

   }

 }

 // Return TRUE if all code paths starting with start_bc_offset end in

 // bytecode athrow or loop.

 bool ClassVerifier::ends_in_athrow(u4 start_bc_offset) {

   ResourceMark rm;

   // Create bytecode stream.

   RawBytecodeStream bcs(method());

   u4 code_length = method()->code_size();

   bcs.set_start(start_bc_offset);

   u4 target;

   // Create stack for storing bytecode start offsets for if* and *switch.

   GrowableArray<u4>* bci_stack = new GrowableArray<u4>(30);

   // Create stack for handlers for try blocks containing this handler.

   GrowableArray<u4>* handler_stack = new GrowableArray<u4>(30);

   // Create list of handlers that have been pushed onto the handler_stack

   // so that handlers embedded inside of their own TRY blocks only get

   // scanned once.

   GrowableArray<u4>* handler_list = new GrowableArray<u4>(30);

   // Create list of visited branch opcodes (goto* and if*).

   GrowableArray<u4>* visited_branches = new GrowableArray<u4>(30);

   ExceptionTable exhandlers(_method());

   while (true) {

     if (bcs.is_last_bytecode()) {

       // if no more starting offsets to parse or if at the end of the

       // method then return false.

       if ((bci_stack->is_empty()) || ((u4)bcs.end_bci() == code_length))

         return false;

       // Pop a bytecode starting offset and scan from there.

       bcs.set_start(bci_stack->pop());

     }

     Bytecodes::Code opcode = bcs.raw_next();

     u4 bci = bcs.bci();

     // If the bytecode is in a TRY block, push its handlers so they

     // will get parsed.

     push_handlers(&exhandlers, handler_list, handler_stack, bci);

     switch (opcode) {

       case Bytecodes::_if_icmpeq:

       case Bytecodes::_if_icmpne:

       case Bytecodes::_if_icmplt:

       case Bytecodes::_if_icmpge:

       case Bytecodes::_if_icmpgt:

       case Bytecodes::_if_icmple:

       case Bytecodes::_ifeq:

       case Bytecodes::_ifne:

       case Bytecodes::_iflt:

       case Bytecodes::_ifge:

       case Bytecodes::_ifgt:

       case Bytecodes::_ifle:

       case Bytecodes::_if_acmpeq:

       case Bytecodes::_if_acmpne:

       case Bytecodes::_ifnull:

       case Bytecodes::_ifnonnull:

         target = bcs.dest();

         if (visited_branches->contains(bci)) {

           if (bci_stack->is_empty()) {

             if (handler_stack->is_empty()) {

               return true;

             } else {

               // Parse the catch handlers for try blocks containing athrow.

               bcs.set_start(handler_stack->pop());

             }

           } else {

             // Pop a bytecode starting offset and scan from there.

             bcs.set_start(bci_stack->pop());

           }

         } else {

           if (target > bci) { // forward branch

             if (target >= code_length) return false;

             // Push the branch target onto the stack.

             bci_stack->push(target);

             // then, scan bytecodes starting with next.

             bcs.set_start(bcs.next_bci());

           } else { // backward branch

             // Push bytecode offset following backward branch onto the stack.

             bci_stack->push(bcs.next_bci());

             // Check bytecodes starting with branch target.

             bcs.set_start(target);

           }

           // Record target so we don't branch here again.

           visited_branches->append(bci);

         }

         break;

       case Bytecodes::_goto:

       case Bytecodes::_goto_w:

         target = (opcode == Bytecodes::_goto ? bcs.dest() : bcs.dest_w());

         if (visited_branches->contains(bci)) {

           if (bci_stack->is_empty()) {

             if (handler_stack->is_empty()) {

               return true;

             } else {

               // Parse the catch handlers for try blocks containing athrow.

               bcs.set_start(handler_stack->pop());

             }

           } else {

             // Been here before, pop new starting offset from stack.

             bcs.set_start(bci_stack->pop());

           }

         } else {

           if (target >= code_length) return false;

           // Continue scanning from the target onward.

           bcs.set_start(target);

           // Record target so we don't branch here again.

           visited_branches->append(bci);

         }

         break;

       // Check that all switch alternatives end in 'athrow' bytecodes. Since it

       // is  difficult to determine where each switch alternative ends, parse

       // each switch alternative until either hit a 'return', 'athrow', or reach

       // the end of the method's bytecodes.  This is gross but should be okay

       // because:

       // 1. tableswitch and lookupswitch byte codes in handlers for ctor explicit

       //    constructor invocations should be rare.

       // 2. if each switch alternative ends in an athrow then the parsing should be

       //    short.  If there is no athrow then it is bogus code, anyway.

       case Bytecodes::_lookupswitch:

       case Bytecodes::_tableswitch:

         {

           address aligned_bcp = (address) round_to((intptr_t)(bcs.bcp() + 1), jintSize);

           u4 default_offset = Bytes::get_Java_u4(aligned_bcp) + bci;

           int keys, delta;

           if (opcode == Bytecodes::_tableswitch) {

             jint low = (jint)Bytes::get_Java_u4(aligned_bcp + jintSize);

             jint high = (jint)Bytes::get_Java_u4(aligned_bcp + 2*jintSize);

             // This is invalid, but let the regular bytecode verifier

             // report this because the user will get a better error message.

             if (low > high) return true;

             keys = high - low + 1;

             delta = 1;

           } else {

             keys = (int)Bytes::get_Java_u4(aligned_bcp + jintSize);

             delta = 2;

           }

           // Invalid, let the regular bytecode verifier deal with it.

           if (keys < 0) return true;

           // Push the offset of the next bytecode onto the stack.

           bci_stack->push(bcs.next_bci());

           // Push the switch alternatives onto the stack.

           for (int i = 0; i < keys; i++) {

             u4 target = bci + (jint)Bytes::get_Java_u4(aligned_bcp+(3+i*delta)*jintSize);

             if (target > code_length) return false;

             bci_stack->push(target);

           }

           // Start bytecode parsing for the switch at the default alternative.

           if (default_offset > code_length) return false;

           bcs.set_start(default_offset);

           break;

         }

       case Bytecodes::_return:

         return false;

       case Bytecodes::_athrow:

         {

           if (bci_stack->is_empty()) {

             if (handler_stack->is_empty()) {

               return true;

             } else {

               // Parse the catch handlers for try blocks containing athrow.

               bcs.set_start(handler_stack->pop());

             }

           } else {

             // Pop a bytecode offset and starting scanning from there.

             bcs.set_start(bci_stack->pop());

           }

         }

         break;

       default:

         ;

     } // end switch

   } // end while loop

   return false;

 }

 void ClassVerifier::verify_invoke_init(

     RawBytecodeStream* bcs, u2 ref_class_index, VerificationType ref_class_type,

     StackMapFrame* current_frame, u4 code_length, bool in_try_block,

     bool *this_uninit, constantPoolHandle cp, StackMapTable* stackmap_table,

     TRAPS) {

   u2 bci = bcs->bci();

   VerificationType type = current_frame->pop_stack(

     VerificationType::reference_check(), CHECK_VERIFY(this));

   if (type == VerificationType::uninitialized_this_type()) {

     // The method must be an <init> method of this class or its superclass

     Klass* superk = current_class()->super();

     if (ref_class_type.name() != current_class()->name() &&

         ref_class_type.name() != superk->name()) {

       verify_error(ErrorContext::bad_type(bci,

           TypeOrigin::implicit(ref_class_type),

           TypeOrigin::implicit(current_type())),

           "Bad <init> method call");

       return;

     }

     // If this invokespecial call is done from inside of a TRY block then make

     // sure that all catch clause paths end in a throw.  Otherwise, this can

     // result in returning an incomplete object.

     if (in_try_block) {

       ExceptionTable exhandlers(_method());

       int exlength = exhandlers.length();

       for(int i = 0; i < exlength; i++) {

         u2 start_pc = exhandlers.start_pc(i);

         u2 end_pc = exhandlers.end_pc(i);

         if (bci >= start_pc && bci < end_pc) {

           if (!ends_in_athrow(exhandlers.handler_pc(i))) {

             verify_error(ErrorContext::bad_code(bci),

               "Bad <init> method call from after the start of a try block");

             return;

           } else if (VerboseVerification) {

             ResourceMark rm;

             tty->print_cr(

               "Survived call to ends_in_athrow(): %s",

               current_class()->name()->as_C_string());

           }

         }

       }

       // Check the exception handler target stackmaps with the locals from the

       // incoming stackmap (before initialize_object() changes them to outgoing

       // state).

       verify_exception_handler_targets(bci, true, current_frame,

                                        stackmap_table, CHECK_VERIFY(this));

     } // in_try_block

     current_frame->initialize_object(type, current_type());

     *this_uninit = true;

   } else if (type.is_uninitialized()) {

     u2 new_offset = type.bci();

     address new_bcp = bcs->bcp() - bci + new_offset;

     if (new_offset > (code_length - 3) || (*new_bcp) != Bytecodes::_new) {

       /* Unreachable?  Stack map parsing ensures valid type and new

        * instructions have a valid BCI. */

       verify_error(ErrorContext::bad_code(new_offset),

                    "Expecting new instruction");

       return;

     }

     u2 new_class_index = Bytes::get_Java_u2(new_bcp + 1);

     verify_cp_class_type(bci, new_class_index, cp, CHECK_VERIFY(this));

     // The method must be an <init> method of the indicated class

     VerificationType new_class_type = cp_index_to_type(

       new_class_index, cp, CHECK_VERIFY(this));

     if (!new_class_type.equals(ref_class_type)) {

       verify_error(ErrorContext::bad_type(bci,

           TypeOrigin::cp(new_class_index, new_class_type),

           TypeOrigin::cp(ref_class_index, ref_class_type)),

           "Call to wrong <init> method");

       return;

     }

     // According to the VM spec, if the referent class is a superclass of the

     // current class, and is in a different runtime package, and the method is

     // protected, then the objectref must be the current class or a subclass

     // of the current class.

     VerificationType objectref_type = new_class_type;

     if (name_in_supers(ref_class_type.name(), current_class())) {

       Klass* ref_klass = load_class(ref_class_type.name(), CHECK);

       Method* m = InstanceKlass::cast(ref_klass)->uncached_lookup_method(

         vmSymbols::object_initializer_name(),

         cp->signature_ref_at(bcs->get_index_u2()), Klass::find_overpass);

       // Do nothing if method is not found.  Let resolution detect the error.

       if (m != NULL) {

         instanceKlassHandle mh(THREAD, m->method_holder());

         if (m->is_protected() && !mh->is_same_class_package(_klass())) {

           bool assignable = current_type().is_assignable_from(

             objectref_type, this, true, CHECK_VERIFY(this));

           if (!assignable) {

             verify_error(ErrorContext::bad_type(bci,

                 TypeOrigin::cp(new_class_index, objectref_type),

                 TypeOrigin::implicit(current_type())),

                 "Bad access to protected <init> method");

             return;

           }

         }

       }

     }

     // Check the exception handler target stackmaps with the locals from the

     // incoming stackmap (before initialize_object() changes them to outgoing

     // state).

     if (in_try_block) {

       verify_exception_handler_targets(bci, *this_uninit, current_frame,

                                        stackmap_table, CHECK_VERIFY(this));

     }

     current_frame->initialize_object(type, new_class_type);

   } else {

     verify_error(ErrorContext::bad_type(bci, current_frame->stack_top_ctx()),

         "Bad operand type when invoking <init>");

     return;

   }

 }

 bool ClassVerifier::is_same_or_direct_interface(

     instanceKlassHandle klass,

     VerificationType klass_type,

     VerificationType ref_class_type) {

   if (ref_class_type.equals(klass_type)) return true;

   Array<Klass*>* local_interfaces = klass->local_interfaces();

   if (local_interfaces != NULL) {

     for (int x = 0; x < local_interfaces->length(); x++) {

       Klass* k = local_interfaces->at(x);

       assert (k != NULL && k->is_interface(), "invalid interface");

       if (ref_class_type.equals(VerificationType::reference_type(k->name()))) {

         return true;

       }

     }

   }

   return false;

 }

 void ClassVerifier::verify_invoke_instructions(

     RawBytecodeStream* bcs, u4 code_length, StackMapFrame* current_frame,

     bool in_try_block, bool *this_uninit, VerificationType return_type,

     constantPoolHandle cp, StackMapTable* stackmap_table, TRAPS) {

   // Make sure the constant pool item is the right type

   u2 index = bcs->get_index_u2();

   Bytecodes::Code opcode = bcs->raw_code();

   unsigned int types;

   switch (opcode) {

     case Bytecodes::_invokeinterface:

       types = 1 << JVM_CONSTANT_InterfaceMethodref;

       break;

     case Bytecodes::_invokedynamic:

       types = 1 << JVM_CONSTANT_InvokeDynamic;

       break;

     case Bytecodes::_invokespecial:

     case Bytecodes::_invokestatic:

       types = (_klass->major_version() < STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION) ?

         (1 << JVM_CONSTANT_Methodref) :

         ((1 << JVM_CONSTANT_InterfaceMethodref) | (1 << JVM_CONSTANT_Methodref));

       break;

     default:

       types = 1 << JVM_CONSTANT_Methodref;

   }

   verify_cp_type(bcs->bci(), index, cp, types, CHECK_VERIFY(this));

   // Get method name and signature

   Symbol* method_name = cp->name_ref_at(index);

   Symbol* method_sig = cp->signature_ref_at(index);

   if (!SignatureVerifier::is_valid_method_signature(method_sig)) {

     class_format_error(

       "Invalid method signature in class %s referenced "

       "from constant pool index %d", _klass->external_name(), index);

     return;

   }

   // Get referenced class type

   VerificationType ref_class_type;

   if (opcode == Bytecodes::_invokedynamic) {

     if (!EnableInvokeDynamic ||

         _klass->major_version() < Verifier::INVOKEDYNAMIC_MAJOR_VERSION) {

         if (!EnableInvokeDynamic) {

             class_format_error("invokedynamic instructions not enabled in this JVM");