duke@435: /*
stefank@2314:  * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #include "precompiled.hpp"
stefank@2314: #include "classfile/stackMapFrame.hpp"
stefank@2314: #include "classfile/verifier.hpp"
stefank@2314: #include "memory/resourceArea.hpp"
stefank@2314: #include "oops/oop.inline.hpp"
coleenp@2497: #include "oops/symbol.hpp"
stefank@2314: #include "runtime/handles.inline.hpp"
stefank@2314: #include "utilities/globalDefinitions.hpp"
duke@435: 
duke@435: StackMapFrame::StackMapFrame(u2 max_locals, u2 max_stack, ClassVerifier* v) :
duke@435:                       _offset(0), _locals_size(0), _stack_size(0), _flags(0),
duke@435:                       _max_locals(max_locals), _max_stack(max_stack),
duke@435:                       _verifier(v) {
duke@435:   Thread* thr = v->thread();
duke@435:   _locals = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, max_locals);
duke@435:   _stack = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, max_stack);
duke@435:   int32_t i;
duke@435:   for(i = 0; i < max_locals; i++) {
duke@435:     _locals[i] = VerificationType::bogus_type();
duke@435:   }
duke@435:   for(i = 0; i < max_stack; i++) {
duke@435:     _stack[i] = VerificationType::bogus_type();
duke@435:   }
duke@435: }
duke@435: 
duke@435: StackMapFrame* StackMapFrame::frame_in_exception_handler(u1 flags) {
duke@435:   Thread* thr = _verifier->thread();
duke@435:   VerificationType* stack = NEW_RESOURCE_ARRAY_IN_THREAD(thr, VerificationType, 1);
duke@435:   StackMapFrame* frame = new StackMapFrame(_offset, flags, _locals_size, 0, _max_locals, _max_stack, _locals, stack, _verifier);
duke@435:   return frame;
duke@435: }
duke@435: 
duke@435: bool StackMapFrame::has_new_object() const {
duke@435:   int32_t i;
duke@435:   for (i = 0; i < _max_locals; i++) {
duke@435:     if (_locals[i].is_uninitialized()) {
duke@435:       return true;
duke@435:     }
duke@435:   }
duke@435:   for (i = 0; i < _stack_size; i++) {
duke@435:     if (_stack[i].is_uninitialized()) {
duke@435:       return true;
duke@435:     }
duke@435:   }
duke@435:   return false;
duke@435: }
duke@435: 
duke@435: void StackMapFrame::initialize_object(
duke@435:     VerificationType old_object, VerificationType new_object) {
duke@435:   int32_t i;
duke@435:   for (i = 0; i < _max_locals; i++) {
duke@435:     if (_locals[i].equals(old_object)) {
duke@435:       _locals[i] = new_object;
duke@435:     }
duke@435:   }
duke@435:   for (i = 0; i < _stack_size; i++) {
duke@435:     if (_stack[i].equals(old_object)) {
duke@435:       _stack[i] = new_object;
duke@435:     }
duke@435:   }
duke@435:   if (old_object == VerificationType::uninitialized_this_type()) {
duke@435:     // "this" has been initialized - reset flags
duke@435:     _flags = 0;
duke@435:   }
duke@435: }
duke@435: 
duke@435: VerificationType StackMapFrame::set_locals_from_arg(
duke@435:     const methodHandle m, VerificationType thisKlass, TRAPS) {
coleenp@2497:   SignatureStream ss(m->signature());
duke@435:   int init_local_num = 0;
duke@435:   if (!m->is_static()) {
duke@435:     init_local_num++;
duke@435:     // add one extra argument for instance method
duke@435:     if (m->name() == vmSymbols::object_initializer_name() &&
duke@435:        thisKlass.name() != vmSymbols::java_lang_Object()) {
duke@435:       _locals[0] = VerificationType::uninitialized_this_type();
duke@435:       _flags |= FLAG_THIS_UNINIT;
duke@435:     } else {
duke@435:       _locals[0] = thisKlass;
duke@435:     }
duke@435:   }
duke@435: 
duke@435:   // local num may be greater than size of parameters because long/double occupies two slots
duke@435:   while(!ss.at_return_type()) {
duke@435:     init_local_num += _verifier->change_sig_to_verificationType(
duke@435:       &ss, &_locals[init_local_num],
duke@435:       CHECK_VERIFY_(verifier(), VerificationType::bogus_type()));
duke@435:     ss.next();
duke@435:   }
duke@435:   _locals_size = init_local_num;
duke@435: 
duke@435:   switch (ss.type()) {
duke@435:     case T_OBJECT:
duke@435:     case T_ARRAY:
duke@435:     {
coleenp@2497:       Symbol* sig = ss.as_symbol(CHECK_(VerificationType::bogus_type()));
coleenp@2497:       // Create another symbol to save as signature stream unreferences
coleenp@2497:       // this symbol.
coleenp@2497:       Symbol* sig_copy =
coleenp@2497:         verifier()->create_temporary_symbol(sig, 0, sig->utf8_length(),
coleenp@2497:                                  CHECK_(VerificationType::bogus_type()));
coleenp@2497:       assert(sig_copy == sig, "symbols don't match");
coleenp@2497:       return VerificationType::reference_type(sig_copy);
duke@435:     }
duke@435:     case T_INT:     return VerificationType::integer_type();
duke@435:     case T_BYTE:    return VerificationType::byte_type();
duke@435:     case T_CHAR:    return VerificationType::char_type();
duke@435:     case T_SHORT:   return VerificationType::short_type();
duke@435:     case T_BOOLEAN: return VerificationType::boolean_type();
duke@435:     case T_FLOAT:   return VerificationType::float_type();
duke@435:     case T_DOUBLE:  return VerificationType::double_type();
duke@435:     case T_LONG:    return VerificationType::long_type();
duke@435:     case T_VOID:    return VerificationType::bogus_type();
duke@435:     default:
duke@435:       ShouldNotReachHere();
duke@435:   }
duke@435:   return VerificationType::bogus_type();
duke@435: }
duke@435: 
duke@435: void StackMapFrame::copy_locals(const StackMapFrame* src) {
duke@435:   int32_t len = src->locals_size() < _locals_size ?
duke@435:     src->locals_size() : _locals_size;
duke@435:   for (int32_t i = 0; i < len; i++) {
duke@435:     _locals[i] = src->locals()[i];
duke@435:   }
duke@435: }
duke@435: 
duke@435: void StackMapFrame::copy_stack(const StackMapFrame* src) {
duke@435:   int32_t len = src->stack_size() < _stack_size ?
duke@435:     src->stack_size() : _stack_size;
duke@435:   for (int32_t i = 0; i < len; i++) {
duke@435:     _stack[i] = src->stack()[i];
duke@435:   }
duke@435: }
duke@435: 
duke@435: 
duke@435: bool StackMapFrame::is_assignable_to(
duke@435:     VerificationType* from, VerificationType* to, int32_t len, TRAPS) const {
duke@435:   for (int32_t i = 0; i < len; i++) {
duke@435:     bool subtype = to[i].is_assignable_from(
coleenp@2497:       from[i], verifier(), THREAD);
duke@435:     if (!subtype) {
duke@435:       return false;
duke@435:     }
duke@435:   }
duke@435:   return true;
duke@435: }
duke@435: 
kamg@2585: bool StackMapFrame::has_flag_match_exception(
kamg@2585:     const StackMapFrame* target) const {
kamg@2585:   // We allow flags of {UninitThis} to assign to {} if-and-only-if the
kamg@2585:   // target frame does not depend upon the current type.
kamg@2585:   // This is slightly too strict, as we need only enforce that the
kamg@2585:   // slots that were initialized by the <init> (the things that were
kamg@2585:   // UninitializedThis before initialize_object() converted them) are unused.
kamg@2585:   // However we didn't save that information so we'll enforce this upon
kamg@2585:   // anything that might have been initialized.  This is a rare situation
kamg@2585:   // and javac never generates code that would end up here, but some profilers
kamg@2585:   // (such as NetBeans) might, when adding exception handlers in <init>
kamg@2585:   // methods to cover the invokespecial instruction.  See 7020118.
kamg@2585: 
kamg@2585:   assert(max_locals() == target->max_locals() &&
kamg@2585:          stack_size() == target->stack_size(), "StackMap sizes must match");
kamg@2585: 
kamg@2585:   VerificationType top = VerificationType::top_type();
kamg@2585:   VerificationType this_type = verifier()->current_type();
kamg@2585: 
kamg@2585:   if (!flag_this_uninit() || target->flags() != 0) {
kamg@2585:     return false;
kamg@2585:   }
kamg@2585: 
kamg@2585:   for (int i = 0; i < target->locals_size(); ++i) {
kamg@2585:     if (locals()[i] == this_type && target->locals()[i] != top) {
kamg@2585:       return false;
kamg@2585:     }
kamg@2585:   }
kamg@2585: 
kamg@2585:   for (int i = 0; i < target->stack_size(); ++i) {
kamg@2585:     if (stack()[i] == this_type && target->stack()[i] != top) {
kamg@2585:       return false;
kamg@2585:     }
kamg@2585:   }
kamg@2585: 
kamg@2585:   return true;
kamg@2585: }
kamg@2585: 
kamg@2754: bool StackMapFrame::is_assignable_to(
kamg@2754:     const StackMapFrame* target, bool is_exception_handler, TRAPS) const {
kamg@2754:   if (_max_locals != target->max_locals() ||
kamg@2754:       _stack_size != target->stack_size()) {
duke@435:     return false;
duke@435:   }
duke@435:   // Only need to compare type elements up to target->locals() or target->stack().
duke@435:   // The remaining type elements in this state can be ignored because they are
duke@435:   // assignable to bogus type.
duke@435:   bool match_locals = is_assignable_to(
duke@435:     _locals, target->locals(), target->locals_size(), CHECK_false);
duke@435:   bool match_stack = is_assignable_to(
duke@435:     _stack, target->stack(), _stack_size, CHECK_false);
duke@435:   bool match_flags = (_flags | target->flags()) == target->flags();
kamg@2585: 
kamg@2585:   return match_locals && match_stack &&
kamg@2754:     (match_flags || (is_exception_handler && has_flag_match_exception(target)));
duke@435: }
duke@435: 
duke@435: VerificationType StackMapFrame::pop_stack_ex(VerificationType type, TRAPS) {
duke@435:   if (_stack_size <= 0) {
duke@435:     verifier()->verify_error(_offset, "Operand stack underflow");
duke@435:     return VerificationType::bogus_type();
duke@435:   }
duke@435:   VerificationType top = _stack[--_stack_size];
duke@435:   bool subtype = type.is_assignable_from(
coleenp@2497:     top, verifier(), CHECK_(VerificationType::bogus_type()));
duke@435:   if (!subtype) {
duke@435:     verifier()->verify_error(_offset, "Bad type on operand stack");
duke@435:     return VerificationType::bogus_type();
duke@435:   }
duke@435:   NOT_PRODUCT( _stack[_stack_size] = VerificationType::bogus_type(); )
duke@435:   return top;
duke@435: }
duke@435: 
duke@435: VerificationType StackMapFrame::get_local(
duke@435:     int32_t index, VerificationType type, TRAPS) {
duke@435:   if (index >= _max_locals) {
duke@435:     verifier()->verify_error(_offset, "Local variable table overflow");
duke@435:     return VerificationType::bogus_type();
duke@435:   }
duke@435:   bool subtype = type.is_assignable_from(_locals[index],
coleenp@2497:     verifier(), CHECK_(VerificationType::bogus_type()));
duke@435:   if (!subtype) {
duke@435:     verifier()->verify_error(_offset, "Bad local variable type");
duke@435:     return VerificationType::bogus_type();
duke@435:   }
duke@435:   if(index >= _locals_size) { _locals_size = index + 1; }
duke@435:   return _locals[index];
duke@435: }
duke@435: 
duke@435: void StackMapFrame::get_local_2(
duke@435:     int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
duke@435:   assert(type1.is_long() || type1.is_double(), "must be long/double");
duke@435:   assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
duke@435:   if (index >= _locals_size - 1) {
duke@435:     verifier()->verify_error(_offset, "get long/double overflows locals");
duke@435:     return;
duke@435:   }
duke@435:   bool subtype1 = type1.is_assignable_from(
coleenp@2497:     _locals[index], verifier(), CHECK);
duke@435:   bool subtype2 = type2.is_assignable_from(
coleenp@2497:     _locals[index+1], verifier(), CHECK);
duke@435:   if (!subtype1 || !subtype2) {
duke@435:     verifier()->verify_error(_offset, "Bad local variable type");
duke@435:     return;
duke@435:   }
duke@435: }
duke@435: 
duke@435: void StackMapFrame::set_local(int32_t index, VerificationType type, TRAPS) {
duke@435:   assert(!type.is_check(), "Must be a real type");
duke@435:   if (index >= _max_locals) {
duke@435:     verifier()->verify_error("Local variable table overflow", _offset);
duke@435:     return;
duke@435:   }
duke@435:   // If type at index is double or long, set the next location to be unusable
duke@435:   if (_locals[index].is_double() || _locals[index].is_long()) {
duke@435:     assert((index + 1) < _locals_size, "Local variable table overflow");
duke@435:     _locals[index + 1] = VerificationType::bogus_type();
duke@435:   }
duke@435:   // If type at index is double_2 or long_2, set the previous location to be unusable
duke@435:   if (_locals[index].is_double2() || _locals[index].is_long2()) {
duke@435:     assert(index >= 1, "Local variable table underflow");
duke@435:     _locals[index - 1] = VerificationType::bogus_type();
duke@435:   }
duke@435:   _locals[index] = type;
duke@435:   if (index >= _locals_size) {
duke@435: #ifdef ASSERT
duke@435:     for (int i=_locals_size; i<index; i++) {
duke@435:       assert(_locals[i] == VerificationType::bogus_type(),
duke@435:              "holes must be bogus type");
duke@435:     }
duke@435: #endif
duke@435:     _locals_size = index + 1;
duke@435:   }
duke@435: }
duke@435: 
duke@435: void StackMapFrame::set_local_2(
duke@435:     int32_t index, VerificationType type1, VerificationType type2, TRAPS) {
duke@435:   assert(type1.is_long() || type1.is_double(), "must be long/double");
duke@435:   assert(type2.is_long2() || type2.is_double2(), "must be long/double_2");
duke@435:   if (index >= _max_locals - 1) {
duke@435:     verifier()->verify_error("Local variable table overflow", _offset);
duke@435:     return;
duke@435:   }
duke@435:   // If type at index+1 is double or long, set the next location to be unusable
duke@435:   if (_locals[index+1].is_double() || _locals[index+1].is_long()) {
duke@435:     assert((index + 2) < _locals_size, "Local variable table overflow");
duke@435:     _locals[index + 2] = VerificationType::bogus_type();
duke@435:   }
duke@435:   // If type at index is double_2 or long_2, set the previous location to be unusable
duke@435:   if (_locals[index].is_double2() || _locals[index].is_long2()) {
duke@435:     assert(index >= 1, "Local variable table underflow");
duke@435:     _locals[index - 1] = VerificationType::bogus_type();
duke@435:   }
duke@435:   _locals[index] = type1;
duke@435:   _locals[index+1] = type2;
duke@435:   if (index >= _locals_size - 1) {
duke@435: #ifdef ASSERT
duke@435:     for (int i=_locals_size; i<index; i++) {
duke@435:       assert(_locals[i] == VerificationType::bogus_type(),
duke@435:              "holes must be bogus type");
duke@435:     }
duke@435: #endif
duke@435:     _locals_size = index + 2;
duke@435:   }
duke@435: }
duke@435: 
duke@435: #ifndef PRODUCT
duke@435: 
duke@435: void StackMapFrame::print() const {
duke@435:   tty->print_cr("stackmap_frame[%d]:", _offset);
duke@435:   tty->print_cr("flags = 0x%x", _flags);
duke@435:   tty->print("locals[%d] = { ", _locals_size);
duke@435:   for (int32_t i = 0; i < _locals_size; i++) {
duke@435:     _locals[i].print_on(tty);
duke@435:   }
duke@435:   tty->print_cr(" }");
duke@435:   tty->print("stack[%d] = { ", _stack_size);
duke@435:   for (int32_t j = 0; j < _stack_size; j++) {
duke@435:     _stack[j].print_on(tty);
duke@435:   }
duke@435:   tty->print_cr(" }");
duke@435: }
duke@435: 
duke@435: #endif