| /* |
| * 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_STACKMAPFRAME_HPP |
| #define SHARE_VM_CLASSFILE_STACKMAPFRAME_HPP |
| |
| #include "classfile/verificationType.hpp" |
| #include "classfile/verifier.hpp" |
| #include "oops/method.hpp" |
| #include "runtime/handles.hpp" |
| #include "runtime/signature.hpp" |
| #include "utilities/exceptions.hpp" |
| |
| // A StackMapFrame represents one frame in the stack map attribute. |
| |
| class TypeContext; |
| |
| enum { |
| FLAG_THIS_UNINIT = 0x01 |
| }; |
| |
| class StackMapFrame : public ResourceObj { |
| private: |
| int32_t _offset; |
| |
| // See comment in StackMapTable about _frame_count about why these |
| // fields are int32_t instead of u2. |
| int32_t _locals_size; // number of valid type elements in _locals |
| int32_t _stack_size; // number of valid type elements in _stack |
| |
| int32_t _stack_mark; // Records the size of the stack prior to an |
| // instruction modification, to allow rewinding |
| // when/if an error occurs. |
| |
| int32_t _max_locals; |
| int32_t _max_stack; |
| |
| u1 _flags; |
| VerificationType* _locals; // local variable type array |
| VerificationType* _stack; // operand stack type array |
| |
| ClassVerifier* _verifier; // the verifier verifying this method |
| |
| StackMapFrame(const StackMapFrame& cp) : |
| _offset(cp._offset), _locals_size(cp._locals_size), |
| _stack_size(cp._stack_size), _stack_mark(cp._stack_mark), |
| _max_locals(cp._max_locals), _max_stack(cp._max_stack), |
| _flags(cp._flags) { |
| _locals = NEW_RESOURCE_ARRAY(VerificationType, _max_locals); |
| for (int i = 0; i < _max_locals; ++i) { |
| if (i < _locals_size) { |
| _locals[i] = cp._locals[i]; |
| } else { |
| _locals[i] = VerificationType::bogus_type(); |
| } |
| } |
| int ss = MAX2(_stack_size, _stack_mark); |
| _stack = NEW_RESOURCE_ARRAY(VerificationType, _max_stack); |
| for (int i = 0; i < _max_stack; ++i) { |
| if (i < ss) { |
| _stack[i] = cp._stack[i]; |
| } else { |
| _stack[i] = VerificationType::bogus_type(); |
| } |
| } |
| _verifier = NULL; |
| } |
| |
| public: |
| // constructors |
| |
| // This constructor is used by the type checker to allocate frames |
| // in type state, which have _max_locals and _max_stack array elements |
| // in _locals and _stack. |
| StackMapFrame(u2 max_locals, u2 max_stack, ClassVerifier* verifier); |
| |
| // This constructor is used to initialize stackmap frames in stackmap table, |
| // which have _locals_size and _stack_size array elements in _locals and _stack. |
| StackMapFrame(int32_t offset, |
| u1 flags, |
| u2 locals_size, |
| u2 stack_size, |
| u2 max_locals, |
| u2 max_stack, |
| VerificationType* locals, |
| VerificationType* stack, |
| ClassVerifier* v) : _offset(offset), _flags(flags), |
| _locals_size(locals_size), |
| _stack_size(stack_size), |
| _stack_mark(-1), |
| _max_locals(max_locals), |
| _max_stack(max_stack), |
| _locals(locals), _stack(stack), |
| _verifier(v) { } |
| |
| static StackMapFrame* copy(StackMapFrame* smf) { |
| return new StackMapFrame(*smf); |
| } |
| |
| inline void set_offset(int32_t offset) { _offset = offset; } |
| inline void set_verifier(ClassVerifier* v) { _verifier = v; } |
| inline void set_flags(u1 flags) { _flags = flags; } |
| inline void set_locals_size(u2 locals_size) { _locals_size = locals_size; } |
| inline void set_stack_size(u2 stack_size) { _stack_size = _stack_mark = stack_size; } |
| inline void clear_stack() { _stack_size = 0; } |
| inline int32_t offset() const { return _offset; } |
| inline ClassVerifier* verifier() const { return _verifier; } |
| inline u1 flags() const { return _flags; } |
| inline int32_t locals_size() const { return _locals_size; } |
| inline VerificationType* locals() const { return _locals; } |
| inline int32_t stack_size() const { return _stack_size; } |
| inline VerificationType* stack() const { return _stack; } |
| inline int32_t max_locals() const { return _max_locals; } |
| inline int32_t max_stack() const { return _max_stack; } |
| inline bool flag_this_uninit() const { return _flags & FLAG_THIS_UNINIT; } |
| |
| // Set locals and stack types to bogus |
| inline void reset() { |
| int32_t i; |
| for (i = 0; i < _max_locals; i++) { |
| _locals[i] = VerificationType::bogus_type(); |
| } |
| for (i = 0; i < _max_stack; i++) { |
| _stack[i] = VerificationType::bogus_type(); |
| } |
| } |
| |
| // Return a StackMapFrame with the same local variable array and empty stack. |
| // Stack array is allocate with unused one element. |
| StackMapFrame* frame_in_exception_handler(u1 flags); |
| |
| // Set local variable type array based on m's signature. |
| VerificationType set_locals_from_arg( |
| const methodHandle m, VerificationType thisKlass, TRAPS); |
| |
| // Search local variable type array and stack type array. |
| // Set every element with type of old_object to new_object. |
| void initialize_object( |
| VerificationType old_object, VerificationType new_object); |
| |
| // Copy local variable type array in src into this local variable type array. |
| void copy_locals(const StackMapFrame* src); |
| |
| // Copy stack type array in src into this stack type array. |
| void copy_stack(const StackMapFrame* src); |
| |
| // Return true if this stack map frame is assignable to target. |
| bool is_assignable_to( |
| const StackMapFrame* target, ErrorContext* ctx, TRAPS) const; |
| |
| inline void set_mark() { |
| #ifdef ASSERT |
| // Put bogus type to indicate it's no longer valid. |
| if (_stack_mark != -1) { |
| for (int i = _stack_mark - 1; i >= _stack_size; --i) { |
| _stack[i] = VerificationType::bogus_type(); |
| } |
| } |
| #endif // def ASSERT |
| _stack_mark = _stack_size; |
| } |
| |
| // Used when an error occurs and we want to reset the stack to the state |
| // it was before operands were popped off. |
| void restore() { |
| if (_stack_mark != -1) { |
| _stack_size = _stack_mark; |
| } |
| } |
| |
| // Push type into stack type array. |
| inline void push_stack(VerificationType type, TRAPS) { |
| assert(!type.is_check(), "Must be a real type"); |
| if (_stack_size >= _max_stack) { |
| verifier()->verify_error( |
| ErrorContext::stack_overflow(_offset, this), |
| "Operand stack overflow"); |
| return; |
| } |
| _stack[_stack_size++] = type; |
| } |
| |
| inline void push_stack_2( |
| VerificationType type1, VerificationType type2, TRAPS) { |
| assert(type1.is_long() || type1.is_double(), "must be long/double"); |
| assert(type2.is_long2() || type2.is_double2(), "must be long/double_2"); |
| if (_stack_size >= _max_stack - 1) { |
| verifier()->verify_error( |
| ErrorContext::stack_overflow(_offset, this), |
| "Operand stack overflow"); |
| return; |
| } |
| _stack[_stack_size++] = type1; |
| _stack[_stack_size++] = type2; |
| } |
| |
| // Pop and return the top type on stack without verifying. |
| inline VerificationType pop_stack(TRAPS) { |
| if (_stack_size <= 0) { |
| verifier()->verify_error( |
| ErrorContext::stack_underflow(_offset, this), |
| "Operand stack underflow"); |
| return VerificationType::bogus_type(); |
| } |
| VerificationType top = _stack[--_stack_size]; |
| return top; |
| } |
| |
| // Pop and return the top type on stack type array after verifying it |
| // is assignable to type. |
| inline VerificationType pop_stack(VerificationType type, TRAPS) { |
| if (_stack_size != 0) { |
| VerificationType top = _stack[_stack_size - 1]; |
| bool subtype = type.is_assignable_from( |
| top, verifier(), false, CHECK_(VerificationType::bogus_type())); |
| if (subtype) { |
| --_stack_size; |
| return top; |
| } |
| } |
| return pop_stack_ex(type, THREAD); |
| } |
| |
| inline void pop_stack_2( |
| VerificationType type1, VerificationType type2, TRAPS) { |
| assert(type1.is_long2() || type1.is_double2(), "must be long/double"); |
| assert(type2.is_long() || type2.is_double(), "must be long/double_2"); |
| if (_stack_size >= 2) { |
| VerificationType top1 = _stack[_stack_size - 1]; |
| bool subtype1 = type1.is_assignable_from(top1, verifier(), false, CHECK); |
| VerificationType top2 = _stack[_stack_size - 2]; |
| bool subtype2 = type2.is_assignable_from(top2, verifier(), false, CHECK); |
| if (subtype1 && subtype2) { |
| _stack_size -= 2; |
| return; |
| } |
| } |
| pop_stack_ex(type1, THREAD); |
| pop_stack_ex(type2, THREAD); |
| } |
| |
| VerificationType local_at(int index) { |
| return _locals[index]; |
| } |
| |
| VerificationType stack_at(int index) { |
| return _stack[index]; |
| } |
| |
| // Uncommon case that throws exceptions. |
| VerificationType pop_stack_ex(VerificationType type, TRAPS); |
| |
| // Return the type at index in local variable array after verifying |
| // it is assignable to type. |
| VerificationType get_local(int32_t index, VerificationType type, TRAPS); |
| // For long/double. |
| void get_local_2( |
| int32_t index, VerificationType type1, VerificationType type2, TRAPS); |
| |
| // Set element at index in local variable array to type. |
| void set_local(int32_t index, VerificationType type, TRAPS); |
| // For long/double. |
| void set_local_2( |
| int32_t index, VerificationType type1, VerificationType type2, TRAPS); |
| |
| // Private auxiliary method used only in is_assignable_to(StackMapFrame). |
| // Returns true if src is assignable to target. |
| int is_assignable_to( |
| VerificationType* src, VerificationType* target, int32_t len, TRAPS) const; |
| |
| TypeOrigin stack_top_ctx(); |
| |
| void print_on(outputStream* str) const; |
| }; |
| |
| #endif // SHARE_VM_CLASSFILE_STACKMAPFRAME_HPP |
