| /* |
| * Copyright (c) 2003, 2016, 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. |
| * |
| */ |
| |
| #ifndef SHARE_VM_CLASSFILE_STACKMAPTABLE_HPP |
| #define SHARE_VM_CLASSFILE_STACKMAPTABLE_HPP |
| |
| #include "classfile/stackMapFrame.hpp" |
| #include "classfile/verifier.hpp" |
| #include "memory/allocation.hpp" |
| #include "oops/constantPool.hpp" |
| #include "oops/method.hpp" |
| #include "utilities/bytes.hpp" |
| #include "utilities/globalDefinitions.hpp" |
| |
| class StackMapReader; |
| |
| // StackMapTable class is the StackMap table used by type checker |
| class StackMapTable : public StackObj { |
| private: |
| // Logically, the _frame_count (as well as many fields in the StackFrame) |
| // should be a u2, but if we defined the variable as that type it will |
| // be difficult to detect/recover from overflow or underflow conditions. |
| // Widening the type and making it signed will help detect these. |
| int32_t _code_length; |
| int32_t _frame_count; // Stackmap frame count |
| StackMapFrame** _frame_array; |
| |
| public: |
| StackMapTable(StackMapReader* reader, StackMapFrame* init_frame, |
| u2 max_locals, u2 max_stack, |
| char* code_data, int code_len, TRAPS); |
| |
| inline int32_t get_frame_count() const { return _frame_count; } |
| inline int get_offset(int index) const { |
| return _frame_array[index]->offset(); |
| } |
| |
| // Match and/or update current_frame to the frame in stackmap table with |
| // specified offset. Return true if the two frames match. |
| bool match_stackmap( |
| StackMapFrame* current_frame, int32_t offset, |
| bool match, bool update, ErrorContext* ctx, TRAPS) const; |
| // Match and/or update current_frame to the frame in stackmap table with |
| // specified offset and frame index. Return true if the two frames match. |
| bool match_stackmap( |
| StackMapFrame* current_frame, int32_t offset, int32_t frame_index, |
| bool match, bool update, ErrorContext* ctx, TRAPS) const; |
| |
| // Check jump instructions. Make sure there are no uninitialized |
| // instances on backward branch. |
| void check_jump_target(StackMapFrame* frame, int32_t target, TRAPS) const; |
| |
| // The following methods are only used inside this class. |
| |
| // Returns the frame array index where the frame with offset is stored. |
| int get_index_from_offset(int32_t offset) const; |
| |
| void print_on(outputStream* str) const; |
| }; |
| |
| class StackMapStream : StackObj { |
| private: |
| Array<u1>* _data; |
| int _index; |
| public: |
| StackMapStream(Array<u1>* ah) |
| : _data(ah), _index(0) { |
| } |
| u1 get_u1(TRAPS) { |
| if (_data == NULL || _index >= _data->length()) { |
| stackmap_format_error("access beyond the end of attribute", CHECK_0); |
| } |
| return _data->at(_index++); |
| } |
| u2 get_u2(TRAPS) { |
| if (_data == NULL || _index >= _data->length() - 1) { |
| stackmap_format_error("access beyond the end of attribute", CHECK_0); |
| } |
| u2 res = Bytes::get_Java_u2(_data->adr_at(_index)); |
| _index += 2; |
| return res; |
| } |
| bool at_end() { |
| return (_data == NULL) || (_index == _data->length()); |
| } |
| static void stackmap_format_error(const char* msg, TRAPS); |
| }; |
| |
| class StackMapReader : StackObj { |
| private: |
| // information about the class and method |
| constantPoolHandle _cp; |
| ClassVerifier* _verifier; |
| StackMapStream* _stream; |
| char* _code_data; |
| int32_t _code_length; |
| |
| // information get from the attribute |
| int32_t _frame_count; // frame count |
| |
| int32_t chop(VerificationType* locals, int32_t length, int32_t chops); |
| VerificationType parse_verification_type(u1* flags, TRAPS); |
| void check_verification_type_array_size( |
| int32_t size, int32_t max_size, TRAPS) { |
| if (size < 0 || size > max_size) { |
| // Since this error could be caused someone rewriting the method |
| // but not knowing to update the stackmap data, we call the the |
| // verifier's error method, which may not throw an exception and |
| // failover to the old verifier instead. |
| _verifier->class_format_error( |
| "StackMapTable format error: bad type array size"); |
| } |
| } |
| |
| enum { |
| SAME_LOCALS_1_STACK_ITEM_EXTENDED = 247, |
| SAME_EXTENDED = 251, |
| FULL = 255 |
| }; |
| |
| public: |
| // Constructor |
| StackMapReader(ClassVerifier* v, StackMapStream* stream, char* code_data, |
| int32_t code_len, TRAPS) : |
| _verifier(v), _stream(stream), |
| _code_data(code_data), _code_length(code_len) { |
| methodHandle m = v->method(); |
| if (m->has_stackmap_table()) { |
| _cp = constantPoolHandle(THREAD, m->constants()); |
| _frame_count = _stream->get_u2(CHECK); |
| } else { |
| // There's no stackmap table present. Frame count and size are 0. |
| _frame_count = 0; |
| } |
| } |
| |
| inline int32_t get_frame_count() const { return _frame_count; } |
| StackMapFrame* next(StackMapFrame* pre_frame, bool first, |
| u2 max_locals, u2 max_stack, TRAPS); |
| |
| void check_end(TRAPS) { |
| if (!_stream->at_end()) { |
| StackMapStream::stackmap_format_error("wrong attribute size", CHECK); |
| } |
| } |
| }; |
| |
| #endif // SHARE_VM_CLASSFILE_STACKMAPTABLE_HPP |