diff -r fd16c54261b3 -r 489c9b5090e2 hotspot/src/share/vm/classfile/stackMapFrame.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/hotspot/src/share/vm/classfile/stackMapFrame.hpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,226 @@ +/* + * Copyright 2003-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + */ + +// A StackMapFrame represents one frame in the stack map attribute. + +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 _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 + + 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), + _max_locals(max_locals), + _max_stack(max_stack), + _locals(locals), _stack(stack), + _verifier(v) { } + + 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_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. + // Return true if an uninitialized object is found. + bool has_new_object() const; + + // 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, TRAPS) const; + + // 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(_offset, "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(_offset, "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(_offset, "Operand stack underflow"); + return VerificationType::bogus_type(); + } + // Put bogus type to indicate it's no longer valid. + // Added to make it consistent with the other pop_stack method. + VerificationType top = _stack[--_stack_size]; + NOT_PRODUCT( _stack[_stack_size] = VerificationType::bogus_type(); ) + 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()->current_class(), + CHECK_(VerificationType::bogus_type())); + if (subtype) { + _stack_size --; + NOT_PRODUCT( _stack[_stack_size] = VerificationType::bogus_type(); ) + 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()->current_class(), CHECK); + VerificationType top2 = _stack[_stack_size - 2]; + bool subtype2 = type2.is_assignable_from( + top2, verifier()->current_class(), CHECK); + if (subtype1 && subtype2) { + _stack_size -= 2; + NOT_PRODUCT( _stack[_stack_size] = VerificationType::bogus_type(); ) + NOT_PRODUCT( _stack[_stack_size+1] = VerificationType::bogus_type(); ) + return; + } + } + pop_stack_ex(type1, THREAD); + pop_stack_ex(type2, THREAD); + } + + // 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. + bool is_assignable_to( + VerificationType* src, VerificationType* target, int32_t len, TRAPS) const; + + // Debugging + void print() const PRODUCT_RETURN; +};