jdk-sandbox: comparison src/hotspot/share/classfile/verifier.cpp

equal deleted inserted replaced

-:4ebc2e2fb97c
+:71c04702a3d5
+/*
+* Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+*
+* This code is free software; you can redistribute it and/or modify it
+* under the terms of the GNU General Public License version 2 only, as
+* published by the Free Software Foundation.
+*
+* This code is distributed in the hope that it will be useful, but WITHOUT
+* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+* FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+* version 2 for more details (a copy is included in the LICENSE file that
+* accompanied this code).
+*
+* You should have received a copy of the GNU General Public License version
+* 2 along with this work; if not, write to the Free Software Foundation,
+* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+*
+* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+* or visit www.oracle.com if you need additional information or have any
+* questions.
+*
+*/
+#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 "logging/log.hpp"
+#include "logging/logStream.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"
+#include "runtime/thread.hpp"
+#include "services/threadService.hpp"
+#include "utilities/align.hpp"
+#include "utilities/bytes.hpp"
+#define NOFAILOVER_MAJOR_VERSION                       51
+#define NONZERO_PADDING_BYTES_IN_SWITCH_MAJOR_VERSION  51
+#define STATIC_METHOD_IN_INTERFACE_MAJOR_VERSION       52
+#define MAX_ARRAY_DIMENSIONS 255
+// 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 (OrderAccess::load_ptr_acquire(&_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) {
+_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;
+}
+void Verifier::trace_class_resolution(Klass* resolve_class, InstanceKlass* verify_class) {
+assert(verify_class != NULL, "Unexpected null verify_class");
+ResourceMark rm;
+Symbol* s = verify_class->source_file_name();
+const char* source_file = (s != NULL ? s->as_C_string() : NULL);
+const char* verify = verify_class->external_name();
+const char* resolve = resolve_class->external_name();
+// print in a single call to reduce interleaving between threads
+if (source_file != NULL) {
+log_debug(class, resolve)("%s %s %s (verification)", verify, resolve, source_file);
+} else {
+log_debug(class, resolve)("%s %s (verification)", verify, resolve);
+}
+}
+// Prints the end-verification message to the appropriate output.
+void Verifier::log_end_verification(outputStream* st, const char* klassName, Symbol* exception_name, TRAPS) {
+if (HAS_PENDING_EXCEPTION) {
+st->print("Verification for %s has", klassName);
+st->print_cr(" exception pending %s ",
+PENDING_EXCEPTION->klass()->external_name());
+} else if (exception_name != NULL) {
+st->print_cr("Verification for %s failed", klassName);
+}
+st->print_cr("End class verification for: %s", klassName);
+}
+bool Verifier::verify(InstanceKlass* klass, Verifier::Mode mode, bool should_verify_class, TRAPS) {
+HandleMark hm(THREAD);
+ResourceMark rm(THREAD);
+// Eagerly allocate the identity hash code for a klass. This is a fallout
+// from 6320749 and 8059924: hash code generator is not supposed to be called
+// during the safepoint, but it allows to sneak the hashcode in during
+// verification. Without this eager hashcode generation, we may end up
+// installing the hashcode during some other operation, which may be at
+// safepoint -- blowing up the checks. It was previously done as the side
+// effect (sic!) for external_name(), but instead of doing that, we opt to
+// explicitly push the hashcode in here. This is signify the following block
+// is IMPORTANT:
+if (klass->java_mirror() != NULL) {
+klass->java_mirror()->identity_hash();
+}
+if (!is_eligible_for_verification(klass, should_verify_class)) {
+return true;
+}
+// Timer includes any side effects of class verification (resolution,
+// etc), but not recursive calls to Verifier::verify().
+JavaThread* jt = (JavaThread*)THREAD;
+PerfClassTraceTime timer(ClassLoader::perf_class_verify_time(),
+ClassLoader::perf_class_verify_selftime(),
+ClassLoader::perf_classes_verified(),
+jt->get_thread_stat()->perf_recursion_counts_addr(),
+jt->get_thread_stat()->perf_timers_addr(),
+PerfClassTraceTime::CLASS_VERIFY);
+// 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.
+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;
+log_info(class, init)("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())) {
+log_info(verification)("Fail over class verification to old verifier for: %s", klassName);
+log_info(class, init)("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);
+}
+LogTarget(Info, class, init) lt1;
+if (lt1.is_enabled()) {
+LogStream ls(lt1);
+log_end_verification(&ls, klassName, exception_name, THREAD);
+}
+LogTarget(Info, verification) lt2;
+if (lt2.is_enabled()) {
+LogStream ls(lt2);
+log_end_verification(&ls, klassName, exception_name, THREAD);
+}
+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);
+Klass* kls =
+SystemDictionary::resolve_or_fail(exception_name, true, CHECK_false);
+if (log_is_enabled(Debug, class, resolve)) {
+Verifier::trace_class_resolution(kls, klass);
+}
+while (kls != 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(InstanceKlass* 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
+// jdk/internal/reflect/SerializationConstructorAccessor.
+// NOTE: this is called too early in the bootstrapping process to be
+// guarded by Universe::is_gte_jdk14x_version().
+// Also for lambda generated code, gte jdk8
+(!is_reflect));
+}
+Symbol* Verifier::inference_verify(
+InstanceKlass* 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);
+log_info(verification)("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(_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(
+InstanceKlass* 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) {
+log_info(verification)("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 (was_recursively_verified()){
+log_info(verification)("Recursive verification detected for: %s", _klass->external_name());
+log_info(class, init)("Recursive verification detected for: %s",
+_klass->external_name());
+}
+}
+void ClassVerifier::verify_method(const methodHandle& m, TRAPS) {
+HandleMark hm(THREAD);
+_method = m;   // initialize _method
+log_info(verification)("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.
+if (was_recursively_verified()) return;
+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));
+LogTarget(Info, verification) lt;
+if (lt.is_enabled()) {
+ResourceMark rm(THREAD);
+LogStream ls(lt);
+stackmap_table.print_on(&ls);
+}
+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;
+LogTarget(Info, verification) lt;
+if (lt.is_enabled()) {
+ResourceMark rm(THREAD);
+LogStream ls(lt);
+current_frame.print_on(&ls);
+lt.print("offset = %d,  opcode = %s", bci, Bytecodes::name(opcode));
+}
+// 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) {
+if (was_recursively_verified()) return;
+verify_exception_handler_targets(
+bci, this_uninit, &current_frame, &stackmap_table, CHECK_VERIFY(this));
+verified_exc_handlers = true;
+}
+if (was_recursively_verified()) return;
+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 :
+// pass TRUE, operand can be an array type for getstatic/putstatic.
+verify_field_instructions(
+&bcs, &current_frame, cp, true, CHECK_VERIFY(this));
+no_control_flow = false; break;
+case Bytecodes::_getfield :
+case Bytecodes::_putfield :
+// pass FALSE, operand can't be an array type for getfield/putfield.
+verify_field_instructions(
+&bcs, &current_frame, cp, false, 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) {
+if (was_recursively_verified()) return;
+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(const 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;
+}
+// Since this method references the constant pool, call was_recursively_verified()
+// before calling this method to make sure a prior class load did not cause the
+// current class to get verified.
+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++) {
+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;
+}
+// Since this method references the constant pool, call was_recursively_verified()
+// before calling this method to make sure a prior class load did not cause the
+// current class to get verified.
+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++) {
+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) {
+if (was_recursively_verified()) return;
+// 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, const 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, const 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, const 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) {
+HandleMark hm(THREAD);
+// Get current loader and protection domain first.
+oop loader = current_class()->class_loader();
+oop protection_domain = current_class()->protection_domain();
+Klass* kls = SystemDictionary::resolve_or_fail(
+name, Handle(THREAD, loader), Handle(THREAD, protection_domain),
+true, THREAD);
+if (log_is_enabled(Debug, class, resolve)) {
+InstanceKlass* cur_class = InstanceKlass::cast(current_class());
+Verifier::trace_class_resolution(kls, cur_class);
+}
+return kls;
+}
+bool ClassVerifier::is_protected_access(InstanceKlass* this_class,
+Klass* target_class,
+Symbol* field_name,
+Symbol* field_sig,
+bool is_method) {
+NoSafepointVerifier 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,
+const 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 = align_up(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 lookupswitch 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 = align_up(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, InstanceKlass* 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,
+const constantPoolHandle& cp,
+bool allow_arrays,
+TRAPS) {
+u2 index = bcs->get_index_u2();
+verify_cp_type(bcs->bci(), index, cp,
+1 << JVM_CONSTANT_Fieldref, CHECK_VERIFY(this));
+// Get field name and signature
+Symbol* field_name = cp->name_ref_at(index);
+Symbol* field_sig = cp->signature_ref_at(index);
+if (!SignatureVerifier::is_valid_type_signature(field_sig)) {
+class_format_error(
+"Invalid signature for field in class %s referenced "
+"from constant pool index %d", _klass->external_name(), index);
+return;
+}
+// Get referenced class type
+VerificationType ref_class_type = cp_ref_index_to_type(
+index, cp, CHECK_VERIFY(this));
+if (!ref_class_type.is_object() &&
+(!allow_arrays || !ref_class_type.is_array())) {
+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
+if (was_recursively_verified()) return;
+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 = align_up(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, const 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 (log_is_enabled(Info, verification)) {
+ResourceMark rm(THREAD);
+log_info(verification)("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).
+if (was_recursively_verified()) return;
+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);
+if (was_recursively_verified()) return;
+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);
+if (was_recursively_verified()) return;
+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) {
+InstanceKlass* mh = 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) {
+if (was_recursively_verified()) return;
+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(
+InstanceKlass* 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,
+const 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 (_klass->major_version() < Verifier::INVOKEDYNAMIC_MAJOR_VERSION) {
+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(
+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));
+if (was_recursively_verified()) return;
+} 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) {
+if (was_recursively_verified()) return;
+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, const 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));
+if (was_recursively_verified()) return;
+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();
+// Check for more than MAX_ARRAY_DIMENSIONS
+length = (int)strlen(component_name);
+if (length > MAX_ARRAY_DIMENSIONS &&
+component_name[MAX_ARRAY_DIMENSIONS - 1] == '[') {
+verify_error(ErrorContext::bad_code(bci),
+"Illegal anewarray instruction, array has more than 255 dimensions");
+}
+// add one dimension to component
+length++;
+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;
+}

changeset 47216	71c04702a3d5
parent 46701	f559541c0daa
child 47634	6a0c42c40cd1