jdk8-mips64-public/hotspot: src/share/vm/classfile/verifier.cpp@40f45911050f (annotated)

src/share/vm/classfile/verifier.cpp@40f45911050f (annotated)

src/share/vm/classfile/verifier.cpp

Thu, 25 Aug 2016 09:23:45 -0400

author: zgu
date: Thu, 25 Aug 2016 09:23:45 -0400
changeset 9969: 40f45911050f
parent 9530: 9fce84e6f51a
child 10012: 73d58f4c918a
permissions: -rw-r--r--

8148854: Class names "SomeClass" and "LSomeClass;" treated by JVM as an equivalent
Summary: Added default format checking of class names loaded by the app class loader
Reviewed-by: andrew

 /*
  * Copyright (c) 1998, 2018, 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.
  *
  */
 #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_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_access_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,
 << 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");
         } else {
             class_format_error("invokedynamic instructions not supported by this class file version (%d), class %s",
                                _klass->major_version(), _klass->external_name());
         }
       return;
     }
   } else {
     ref_class_type = cp_ref_index_to_type(index, cp, CHECK_VERIFY(this));
   }
   // For a small signature length, we just allocate 128 bytes instead
   // of parsing the signature once to find its size.
   // -3 is for '(', ')' and return descriptor; multiply by 2 is for
   // longs/doubles to be consertive.
   assert(sizeof(VerificationType) == sizeof(uintptr_t),
         "buffer type must match VerificationType size");
   uintptr_t on_stack_sig_types_buffer[128];
   // If we make a VerificationType[128] 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.
   VerificationType* sig_types;
   int size = (method_sig->utf8_length() - 3) * 2;
   if (size > 128) {
     // Long and double occupies two slots here.
     ArgumentSizeComputer size_it(method_sig);
     size = size_it.size();
     sig_types = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, VerificationType, size);
   } else{
     sig_types = (VerificationType*)on_stack_sig_types_buffer;
   }
   SignatureStream sig_stream(method_sig);
   int sig_i = 0;
   while (!sig_stream.at_return_type()) {
     sig_i += change_sig_to_verificationType(
       &sig_stream, &sig_types[sig_i], CHECK_VERIFY(this));
     sig_stream.next();
   }
   int nargs = sig_i;
 #ifdef ASSERT
   {
     ArgumentSizeComputer size_it(method_sig);
     assert(nargs == size_it.size(), "Argument sizes do not match");
     assert(nargs <= (method_sig->utf8_length() - 3) * 2, "estimate of max size isn't conservative enough");
   }
 #endif
   // Check instruction operands
   u2 bci = bcs->bci();
   if (opcode == Bytecodes::_invokeinterface) {
     address bcp = bcs->bcp();
     // 4905268: count operand in invokeinterface should be nargs+1, not nargs.
     // JSR202 spec: The count operand of an invokeinterface instruction is valid if it is
     // the difference between the size of the operand stack before and after the instruction
     // executes.
     if (*(bcp+3) != (nargs+1)) {
       verify_error(ErrorContext::bad_code(bci),
           "Inconsistent args count operand in invokeinterface");
       return;
     }
     if (*(bcp+4) != 0) {
       verify_error(ErrorContext::bad_code(bci),
           "Fourth operand byte of invokeinterface must be zero");
       return;
     }
   }
   if (opcode == Bytecodes::_invokedynamic) {
     address bcp = bcs->bcp();
     if (*(bcp+3) != 0 || *(bcp+4) != 0) {
       verify_error(ErrorContext::bad_code(bci),
           "Third and fourth operand bytes of invokedynamic must be zero");
       return;
     }
   }
   if (method_name->byte_at(0) == '<') {
     // Make sure <init> can only be invoked by invokespecial
     if (opcode != Bytecodes::_invokespecial ||
         method_name != vmSymbols::object_initializer_name()) {
       verify_error(ErrorContext::bad_code(bci),
           "Illegal call to internal method");
       return;
     }
   } else if (opcode == Bytecodes::_invokespecial
              && !is_same_or_direct_interface(current_class(), current_type(), ref_class_type)
              && !ref_class_type.equals(VerificationType::reference_type(
                   current_class()->super()->name()))) {
     bool subtype = false;
     bool have_imr_indirect = cp->tag_at(index).value() == JVM_CONSTANT_InterfaceMethodref;
     if (!current_class()->is_anonymous()) {
       subtype = ref_class_type.is_assignable_from(
                  current_type(), this, false, CHECK_VERIFY(this));
     } else {
       VerificationType host_klass_type =
                         VerificationType::reference_type(current_class()->host_klass()->name());
       subtype = ref_class_type.is_assignable_from(host_klass_type, this, false, CHECK_VERIFY(this));
       // If invokespecial of IMR, need to recheck for same or
       // direct interface relative to the host class
       have_imr_indirect = (have_imr_indirect &&
                            !is_same_or_direct_interface(
                              InstanceKlass::cast(current_class()->host_klass()),
                              host_klass_type, ref_class_type));
     }
     if (!subtype) {
       verify_error(ErrorContext::bad_code(bci),
           "Bad invokespecial instruction: "
           "current class isn't assignable to reference class.");
        return;
     } else if (have_imr_indirect) {
       verify_error(ErrorContext::bad_code(bci),
           "Bad invokespecial instruction: "
           "interface method reference is in an indirect superinterface.");
       return;
     }
   }
   // Match method descriptor with operand stack
   for (int i = nargs - 1; i >= 0; i--) {  // Run backwards
     current_frame->pop_stack(sig_types[i], CHECK_VERIFY(this));
   }
   // Check objectref on operand stack
   if (opcode != Bytecodes::_invokestatic &&
       opcode != Bytecodes::_invokedynamic) {
     if (method_name == vmSymbols::object_initializer_name()) {  // <init> method
       verify_invoke_init(bcs, index, ref_class_type, current_frame,
         code_length, in_try_block, this_uninit, cp, stackmap_table,
         CHECK_VERIFY(this));
     } else {   // other methods
       // Ensures that target class is assignable to method class.
       if (opcode == Bytecodes::_invokespecial) {
         if (!current_class()->is_anonymous()) {
           current_frame->pop_stack(current_type(), CHECK_VERIFY(this));
         } else {
           // anonymous class invokespecial calls: check if the
           // objectref is a subtype of the host_klass of the current class
           // to allow an anonymous class to reference methods in the host_klass
           VerificationType top = current_frame->pop_stack(CHECK_VERIFY(this));
           VerificationType hosttype =
             VerificationType::reference_type(current_class()->host_klass()->name());
           bool subtype = hosttype.is_assignable_from(top, this, false, CHECK_VERIFY(this));
           if (!subtype) {
             verify_error( ErrorContext::bad_type(current_frame->offset(),
               current_frame->stack_top_ctx(),
               TypeOrigin::implicit(top)),
               "Bad type on operand stack");
             return;
           }
         }
       } else if (opcode == Bytecodes::_invokevirtual) {
         VerificationType stack_object_type =
           current_frame->pop_stack(ref_class_type, CHECK_VERIFY(this));
         if (current_type() != stack_object_type) {
           assert(cp->cache() == NULL, "not rewritten yet");
           Symbol* ref_class_name =
             cp->klass_name_at(cp->klass_ref_index_at(index));
           // See the comments in verify_field_instructions() for
           // the rationale behind this.
           if (name_in_supers(ref_class_name, current_class())) {
             Klass* ref_class = load_class(ref_class_name, CHECK);
             if (is_protected_access(
                   _klass, ref_class, method_name, method_sig, true)) {
               // It's protected access, check if stack object is
               // assignable to current class.
               bool is_assignable = current_type().is_assignable_from(
                 stack_object_type, this, true, CHECK_VERIFY(this));
               if (!is_assignable) {
                 if (ref_class_type.name() == vmSymbols::java_lang_Object()
                     && stack_object_type.is_array()
                     && method_name == vmSymbols::clone_name()) {
                   // Special case: arrays pretend to implement public Object
                   // clone().
                 } else {
                   verify_error(ErrorContext::bad_type(bci,
                       current_frame->stack_top_ctx(),
                       TypeOrigin::implicit(current_type())),
                       "Bad access to protected data in invokevirtual");
                   return;
                 }
               }
             }
           }
         }
       } else {
         assert(opcode == Bytecodes::_invokeinterface, "Unexpected opcode encountered");
         current_frame->pop_stack(ref_class_type, CHECK_VERIFY(this));
       }
     }
   }
   // Push the result type.
   if (sig_stream.type() != T_VOID) {
     if (method_name == vmSymbols::object_initializer_name()) {
       // <init> method must have a void return type
       /* Unreachable?  Class file parser verifies that methods with '<' have
        * void return */
       verify_error(ErrorContext::bad_code(bci),
           "Return type must be void in <init> method");
       return;
     }
     VerificationType return_type[2];
     int n = change_sig_to_verificationType(
       &sig_stream, return_type, CHECK_VERIFY(this));
     for (int i = 0; i < n; i++) {
       current_frame->push_stack(return_type[i], CHECK_VERIFY(this)); // push types backwards
     }
   }
 }
 VerificationType ClassVerifier::get_newarray_type(
     u2 index, u2 bci, TRAPS) {
   const char* from_bt[] = {
     NULL, NULL, NULL, NULL, "[Z", "[C", "[F", "[D", "[B", "[S", "[I", "[J",
   };
   if (index < T_BOOLEAN || index > T_LONG) {
     verify_error(ErrorContext::bad_code(bci), "Illegal newarray instruction");
     return VerificationType::bogus_type();
   }
   // from_bt[index] contains the array signature which has a length of 2
   Symbol* sig = create_temporary_symbol(
     from_bt[index], 2, CHECK_(VerificationType::bogus_type()));
   return VerificationType::reference_type(sig);
 }
 void ClassVerifier::verify_anewarray(
     u2 bci, u2 index, constantPoolHandle cp,
     StackMapFrame* current_frame, TRAPS) {
   verify_cp_class_type(bci, index, cp, CHECK_VERIFY(this));
   current_frame->pop_stack(
     VerificationType::integer_type(), CHECK_VERIFY(this));
   VerificationType component_type =
     cp_index_to_type(index, cp, CHECK_VERIFY(this));
   int length;
   char* arr_sig_str;
   if (component_type.is_array()) {     // it's an array
     const char* component_name = component_type.name()->as_utf8();
     // add one dimension to component
     length = (int)strlen(component_name) + 1;
     arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length);
     arr_sig_str[0] = '[';
     strncpy(&arr_sig_str[1], component_name, length - 1);
   } else {         // it's an object or interface
     const char* component_name = component_type.name()->as_utf8();
     // add one dimension to component with 'L' prepended and ';' postpended.
     length = (int)strlen(component_name) + 3;
     arr_sig_str = NEW_RESOURCE_ARRAY_IN_THREAD(THREAD, char, length);
     arr_sig_str[0] = '[';
     arr_sig_str[1] = 'L';
     strncpy(&arr_sig_str[2], component_name, length - 2);
     arr_sig_str[length - 1] = ';';
   }
   Symbol* arr_sig = create_temporary_symbol(
     arr_sig_str, length, CHECK_VERIFY(this));
   VerificationType new_array_type = VerificationType::reference_type(arr_sig);
   current_frame->push_stack(new_array_type, CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_iload(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->get_local(
     index, VerificationType::integer_type(), CHECK_VERIFY(this));
   current_frame->push_stack(
     VerificationType::integer_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_lload(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->get_local_2(
     index, VerificationType::long_type(),
     VerificationType::long2_type(), CHECK_VERIFY(this));
   current_frame->push_stack_2(
     VerificationType::long_type(),
     VerificationType::long2_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_fload(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->get_local(
     index, VerificationType::float_type(), CHECK_VERIFY(this));
   current_frame->push_stack(
     VerificationType::float_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_dload(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->get_local_2(
     index, VerificationType::double_type(),
     VerificationType::double2_type(), CHECK_VERIFY(this));
   current_frame->push_stack_2(
     VerificationType::double_type(),
     VerificationType::double2_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_aload(u2 index, StackMapFrame* current_frame, TRAPS) {
   VerificationType type = current_frame->get_local(
     index, VerificationType::reference_check(), CHECK_VERIFY(this));
   current_frame->push_stack(type, CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_istore(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->pop_stack(
     VerificationType::integer_type(), CHECK_VERIFY(this));
   current_frame->set_local(
     index, VerificationType::integer_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_lstore(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->pop_stack_2(
     VerificationType::long2_type(),
     VerificationType::long_type(), CHECK_VERIFY(this));
   current_frame->set_local_2(
     index, VerificationType::long_type(),
     VerificationType::long2_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_fstore(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->pop_stack(VerificationType::float_type(), CHECK_VERIFY(this));
   current_frame->set_local(
     index, VerificationType::float_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_dstore(u2 index, StackMapFrame* current_frame, TRAPS) {
   current_frame->pop_stack_2(
     VerificationType::double2_type(),
     VerificationType::double_type(), CHECK_VERIFY(this));
   current_frame->set_local_2(
     index, VerificationType::double_type(),
     VerificationType::double2_type(), CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_astore(u2 index, StackMapFrame* current_frame, TRAPS) {
   VerificationType type = current_frame->pop_stack(
     VerificationType::reference_check(), CHECK_VERIFY(this));
   current_frame->set_local(index, type, CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_iinc(u2 index, StackMapFrame* current_frame, TRAPS) {
   VerificationType type = current_frame->get_local(
     index, VerificationType::integer_type(), CHECK_VERIFY(this));
   current_frame->set_local(index, type, CHECK_VERIFY(this));
 }
 void ClassVerifier::verify_return_value(
     VerificationType return_type, VerificationType type, u2 bci,
     StackMapFrame* current_frame, TRAPS) {
   if (return_type == VerificationType::bogus_type()) {
     verify_error(ErrorContext::bad_type(bci,
         current_frame->stack_top_ctx(), TypeOrigin::signature(return_type)),
         "Method expects a return value");
     return;
   }
   bool match = return_type.is_assignable_from(type, this, false, CHECK_VERIFY(this));
   if (!match) {
     verify_error(ErrorContext::bad_type(bci,
         current_frame->stack_top_ctx(), TypeOrigin::signature(return_type)),
         "Bad return type");
     return;
   }
 }
 // The verifier creates symbols which are substrings of Symbols.
 // These are stored in the verifier until the end of verification so that
 // they can be reference counted.
 Symbol* ClassVerifier::create_temporary_symbol(const Symbol *s, int begin,
                                                int end, TRAPS) {
   Symbol* sym = SymbolTable::new_symbol(s, begin, end, CHECK_NULL);
   _symbols->push(sym);
   return sym;
 }
 Symbol* ClassVerifier::create_temporary_symbol(const char *s, int length, TRAPS) {
   Symbol* sym = SymbolTable::new_symbol(s, length, CHECK_NULL);
   _symbols->push(sym);
   return sym;
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/classfile/verifier.cpp@40f45911050f (annotated)

src/share/vm/classfile/verifier.cpp