aoqi@0: /*
aoqi@0:  * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0:  *
aoqi@0:  * This code is free software; you can redistribute it and/or modify it
aoqi@0:  * under the terms of the GNU General Public License version 2 only, as
aoqi@0:  * published by the Free Software Foundation.
aoqi@0:  *
aoqi@0:  * This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
aoqi@0:  * version 2 for more details (a copy is included in the LICENSE file that
aoqi@0:  * accompanied this code).
aoqi@0:  *
aoqi@0:  * You should have received a copy of the GNU General Public License version
aoqi@0:  * 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0:  *
aoqi@0:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0:  * or visit www.oracle.com if you need additional information or have any
aoqi@0:  * questions.
aoqi@0:  *
aoqi@0:  */
aoqi@0: 
aoqi@0: #ifndef SHARE_VM_CI_CISTREAMS_HPP
aoqi@0: #define SHARE_VM_CI_CISTREAMS_HPP
aoqi@0: 
aoqi@0: #include "ci/ciClassList.hpp"
aoqi@0: #include "ci/ciExceptionHandler.hpp"
aoqi@0: #include "ci/ciInstanceKlass.hpp"
aoqi@0: #include "ci/ciMethod.hpp"
aoqi@0: #include "interpreter/bytecode.hpp"
aoqi@0: 
aoqi@0: // ciBytecodeStream
aoqi@0: //
aoqi@0: // The class is used to iterate over the bytecodes of a method.
aoqi@0: // It hides the details of constant pool structure/access by
aoqi@0: // providing accessors for constant pool items.  It returns only pure
aoqi@0: // Java bytecodes; VM-internal _fast bytecodes are translated back to
aoqi@0: // their original form during iteration.
aoqi@0: class ciBytecodeStream : StackObj {
aoqi@0: private:
aoqi@0:   // Handling for the weird bytecodes
aoqi@0:   Bytecodes::Code next_wide_or_table(Bytecodes::Code); // Handle _wide & complicated inline table
aoqi@0: 
aoqi@0:   static Bytecodes::Code check_java(Bytecodes::Code c) {
aoqi@0:     assert(Bytecodes::is_java_code(c), "should not return _fast bytecodes");
aoqi@0:     return c;
aoqi@0:   }
aoqi@0: 
aoqi@0:   static Bytecodes::Code check_defined(Bytecodes::Code c) {
aoqi@0:     assert(Bytecodes::is_defined(c), "");
aoqi@0:     return c;
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciMethod* _method;           // the method
aoqi@0:   ciInstanceKlass* _holder;
aoqi@0:   address _bc_start;            // Start of current bytecode for table
aoqi@0:   address _was_wide;            // Address past last wide bytecode
aoqi@0:   jint* _table_base;            // Aligned start of last table or switch
aoqi@0: 
aoqi@0:   address _start;                  // Start of bytecodes
aoqi@0:   address _end;                    // Past end of bytecodes
aoqi@0:   address _pc;                     // Current PC
aoqi@0:   Bytecodes::Code _bc;             // Current bytecode
aoqi@0:   Bytecodes::Code _raw_bc;         // Current bytecode, raw form
aoqi@0: 
aoqi@0:   void reset( address base, unsigned int size ) {
aoqi@0:     _bc_start =_was_wide = 0;
aoqi@0:     _start = _pc = base; _end = base + size;
aoqi@0:   }
aoqi@0: 
aoqi@0:   void assert_wide(bool require_wide) const {
aoqi@0:     if (require_wide)
aoqi@0:          { assert(is_wide(),  "must be a wide instruction"); }
aoqi@0:     else { assert(!is_wide(), "must not be a wide instruction"); }
aoqi@0:   }
aoqi@0: 
aoqi@0:   Bytecode bytecode() const { return Bytecode(this, _bc_start); }
aoqi@0:   Bytecode next_bytecode() const { return Bytecode(this, _pc); }
aoqi@0: 
aoqi@0: public:
aoqi@0:   // End-Of-Bytecodes
aoqi@0:   static Bytecodes::Code EOBC() {
aoqi@0:     return Bytecodes::_illegal;
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciBytecodeStream(ciMethod* m) {
aoqi@0:     reset_to_method(m);
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciBytecodeStream() {
aoqi@0:     reset_to_method(NULL);
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciMethod* method() const { return _method; }
aoqi@0: 
aoqi@0:   void reset_to_method(ciMethod* m) {
aoqi@0:     _method = m;
aoqi@0:     if (m == NULL) {
aoqi@0:       _holder = NULL;
aoqi@0:       reset(NULL, 0);
aoqi@0:     } else {
aoqi@0:       _holder = m->holder();
aoqi@0:       reset(m->code(), m->code_size());
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   void reset_to_bci( int bci );
aoqi@0: 
aoqi@0:   // Force the iterator to report a certain bci.
aoqi@0:   void force_bci(int bci);
aoqi@0: 
aoqi@0:   void set_max_bci( int max ) {
aoqi@0:     _end = _start + max;
aoqi@0:   }
aoqi@0: 
aoqi@0:   address cur_bcp() const       { return _bc_start; }  // Returns bcp to current instruction
aoqi@0:   int next_bci() const          { return _pc - _start; }
aoqi@0:   int cur_bci() const           { return _bc_start - _start; }
aoqi@0:   int instruction_size() const  { return _pc - _bc_start; }
aoqi@0: 
aoqi@0:   Bytecodes::Code cur_bc() const{ return check_java(_bc); }
aoqi@0:   Bytecodes::Code cur_bc_raw() const { return check_defined(_raw_bc); }
aoqi@0:   Bytecodes::Code next_bc()     { return Bytecodes::java_code((Bytecodes::Code)* _pc); }
aoqi@0: 
aoqi@0:   // Return current ByteCode and increment PC to next bytecode, skipping all
aoqi@0:   // intermediate constants.  Returns EOBC at end.
aoqi@0:   // Expected usage:
aoqi@0:   //     ciBytecodeStream iter(m);
aoqi@0:   //     while (iter.next() != ciBytecodeStream::EOBC()) { ... }
aoqi@0:   Bytecodes::Code next() {
aoqi@0:     _bc_start = _pc;                        // Capture start of bc
aoqi@0:     if( _pc >= _end ) return EOBC();        // End-Of-Bytecodes
aoqi@0: 
aoqi@0:     // Fetch Java bytecode
aoqi@0:     // All rewritten bytecodes maintain the size of original bytecode.
aoqi@0:     _bc = Bytecodes::java_code(_raw_bc = (Bytecodes::Code)*_pc);
aoqi@0:     int csize = Bytecodes::length_for(_bc); // Expected size
aoqi@0:     _pc += csize;                           // Bump PC past bytecode
aoqi@0:     if (csize == 0) {
aoqi@0:       _bc = next_wide_or_table(_bc);
aoqi@0:     }
aoqi@0:     return check_java(_bc);
aoqi@0:   }
aoqi@0: 
aoqi@0:   bool is_wide() const { return ( _pc == _was_wide ); }
aoqi@0: 
aoqi@0:   // Does this instruction contain an index which refes into the CP cache?
aoqi@0:   bool has_cache_index() const { return Bytecodes::uses_cp_cache(cur_bc_raw()); }
aoqi@0: 
aoqi@0:   bool has_optional_appendix() { return Bytecodes::has_optional_appendix(cur_bc_raw()); }
aoqi@0: 
aoqi@0:   int get_index_u1() const {
aoqi@0:     return bytecode().get_index_u1(cur_bc_raw());
aoqi@0:   }
aoqi@0: 
aoqi@0:   int get_index_u1_cpcache() const {
aoqi@0:     return bytecode().get_index_u1_cpcache(cur_bc_raw());
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get a byte index following this bytecode.
aoqi@0:   // If prefixed with a wide bytecode, get a wide index.
aoqi@0:   int get_index() const {
aoqi@0:     assert(!has_cache_index(), "else use cpcache variant");
aoqi@0:     return (_pc == _was_wide)   // was widened?
aoqi@0:       ? get_index_u2(true)      // yes, return wide index
aoqi@0:       : get_index_u1();         // no, return narrow index
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get 2-byte index (byte swapping depending on which bytecode)
aoqi@0:   int get_index_u2(bool is_wide = false) const {
aoqi@0:     return bytecode().get_index_u2(cur_bc_raw(), is_wide);
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get 2-byte index in native byte order.  (Rewriter::rewrite makes these.)
aoqi@0:   int get_index_u2_cpcache() const {
aoqi@0:     return bytecode().get_index_u2_cpcache(cur_bc_raw());
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get 4-byte index, for invokedynamic.
aoqi@0:   int get_index_u4() const {
aoqi@0:     return bytecode().get_index_u4(cur_bc_raw());
aoqi@0:   }
aoqi@0: 
aoqi@0:   bool has_index_u4() const {
aoqi@0:     return bytecode().has_index_u4(cur_bc_raw());
aoqi@0:   }
aoqi@0: 
aoqi@0:   // Get dimensions byte (multinewarray)
aoqi@0:   int get_dimensions() const { return *(unsigned char*)(_pc-1); }
aoqi@0: 
aoqi@0:   // Sign-extended index byte/short, no widening
aoqi@0:   int get_constant_u1()                     const { return bytecode().get_constant_u1(instruction_size()-1, cur_bc_raw()); }
aoqi@0:   int get_constant_u2(bool is_wide = false) const { return bytecode().get_constant_u2(instruction_size()-2, cur_bc_raw(), is_wide); }
aoqi@0: 
aoqi@0:   // Get a byte signed constant for "iinc".  Invalid for other bytecodes.
aoqi@0:   // If prefixed with a wide bytecode, get a wide constant
aoqi@0:   int get_iinc_con() const {return (_pc==_was_wide) ? (jshort) get_constant_u2(true) : (jbyte) get_constant_u1();}
aoqi@0: 
aoqi@0:   // 2-byte branch offset from current pc
aoqi@0:   int get_dest() const {
aoqi@0:     return cur_bci() + bytecode().get_offset_s2(cur_bc_raw());
aoqi@0:   }
aoqi@0: 
aoqi@0:   // 2-byte branch offset from next pc
aoqi@0:   int next_get_dest() const {
aoqi@0:     assert(_pc < _end, "");
aoqi@0:     return next_bci() + next_bytecode().get_offset_s2(Bytecodes::_ifeq);
aoqi@0:   }
aoqi@0: 
aoqi@0:   // 4-byte branch offset from current pc
aoqi@0:   int get_far_dest() const {
aoqi@0:     return cur_bci() + bytecode().get_offset_s4(cur_bc_raw());
aoqi@0:   }
aoqi@0: 
aoqi@0:   // For a lookup or switch table, return target destination
aoqi@0:   int get_int_table( int index ) const {
aoqi@0:     return Bytes::get_Java_u4((address)&_table_base[index]); }
aoqi@0: 
aoqi@0:   // For tableswitch - get length of offset part
aoqi@0:   int get_tableswitch_length()  { return get_int_table(2)-get_int_table(1)+1; }
aoqi@0: 
aoqi@0:   int get_dest_table( int index ) const {
aoqi@0:     return cur_bci() + get_int_table(index); }
aoqi@0: 
aoqi@0:   // --- Constant pool access ---
aoqi@0:   int get_constant_raw_index() const;
aoqi@0:   int get_constant_pool_index() const;
aoqi@0:   int get_constant_cache_index() const;
aoqi@0:   int get_field_index();
aoqi@0:   int get_method_index();
aoqi@0: 
aoqi@0:   // If this bytecode is a new, newarray, multianewarray, instanceof,
aoqi@0:   // or checkcast, get the referenced klass.
aoqi@0:   ciKlass* get_klass(bool& will_link);
aoqi@0:   int get_klass_index() const;
aoqi@0: 
aoqi@0:   // If this bytecode is one of the ldc variants, get the referenced
aoqi@0:   // constant.  Do not attempt to resolve it, since that would require
aoqi@0:   // execution of Java code.  If it is not resolved, return an unloaded
aoqi@0:   // object (ciConstant.as_object()->is_loaded() == false).
aoqi@0:   ciConstant get_constant();
aoqi@0:   constantTag get_constant_pool_tag(int index) const;
aoqi@0: 
aoqi@0:   // True if the klass-using bytecode points to an unresolved klass
aoqi@0:   bool is_unresolved_klass() const {
aoqi@0:     constantTag tag = get_constant_pool_tag(get_klass_index());
aoqi@0:     return tag.is_unresolved_klass();
aoqi@0:   }
aoqi@0: 
aoqi@0:   // If this bytecode is one of get_field, get_static, put_field,
aoqi@0:   // or put_static, get the referenced field.
aoqi@0:   ciField* get_field(bool& will_link);
aoqi@0: 
aoqi@0:   ciInstanceKlass* get_declared_field_holder();
aoqi@0:   int      get_field_holder_index();
aoqi@0:   int      get_field_signature_index();
aoqi@0: 
aoqi@0:   ciMethod*     get_method(bool& will_link, ciSignature* *declared_signature_result);
aoqi@0:   bool          has_appendix();
aoqi@0:   ciObject*     get_appendix();
aoqi@0:   bool          has_method_type();
aoqi@0:   ciMethodType* get_method_type();
aoqi@0:   ciKlass*      get_declared_method_holder();
aoqi@0:   int           get_method_holder_index();
aoqi@0:   int           get_method_signature_index();
aoqi@0: 
aoqi@0:   // Get the resolved references arrays from the constant pool
aoqi@0:   ciObjArray* get_resolved_references();
aoqi@0: };
aoqi@0: 
aoqi@0: 
aoqi@0: // ciSignatureStream
aoqi@0: //
aoqi@0: // The class is used to iterate over the elements of a method signature.
aoqi@0: class ciSignatureStream : public StackObj {
aoqi@0: private:
aoqi@0:   ciSignature* _sig;
aoqi@0:   int          _pos;
aoqi@0:   // holder is a method's holder
aoqi@0:   ciKlass*     _holder;
aoqi@0: public:
aoqi@0:   ciSignatureStream(ciSignature* signature, ciKlass* holder = NULL) {
aoqi@0:     _sig = signature;
aoqi@0:     _pos = 0;
aoqi@0:     _holder = holder;
aoqi@0:   }
aoqi@0: 
aoqi@0:   bool at_return_type() { return _pos == _sig->count(); }
aoqi@0: 
aoqi@0:   bool is_done() { return _pos > _sig->count(); }
aoqi@0: 
aoqi@0:   void next() {
aoqi@0:     if (_pos <= _sig->count()) {
aoqi@0:       _pos++;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciType* type() {
aoqi@0:     if (at_return_type()) {
aoqi@0:       return _sig->return_type();
aoqi@0:     } else {
aoqi@0:       return _sig->type_at(_pos);
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   // next klass in the signature
aoqi@0:   ciKlass* next_klass() {
aoqi@0:     ciKlass* sig_k;
aoqi@0:     if (_holder != NULL) {
aoqi@0:       sig_k = _holder;
aoqi@0:       _holder = NULL;
aoqi@0:     } else {
aoqi@0:       while (!type()->is_klass()) {
aoqi@0:         next();
aoqi@0:       }
aoqi@0:       assert(!at_return_type(), "passed end of signature");
aoqi@0:       sig_k = type()->as_klass();
aoqi@0:       next();
aoqi@0:     }
aoqi@0:     return sig_k;
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: 
aoqi@0: // ciExceptionHandlerStream
aoqi@0: //
aoqi@0: // The class is used to iterate over the exception handlers of
aoqi@0: // a method.
aoqi@0: class ciExceptionHandlerStream : public StackObj {
aoqi@0: private:
aoqi@0:   // The method whose handlers we are traversing
aoqi@0:   ciMethod* _method;
aoqi@0: 
aoqi@0:   // Our current position in the list of handlers
aoqi@0:   int        _pos;
aoqi@0:   int        _end;
aoqi@0: 
aoqi@0:   ciInstanceKlass*  _exception_klass;
aoqi@0:   int        _bci;
aoqi@0:   bool       _is_exact;
aoqi@0: 
aoqi@0: public:
aoqi@0:   ciExceptionHandlerStream(ciMethod* method) {
aoqi@0:     _method = method;
aoqi@0: 
aoqi@0:     // Force loading of method code and handlers.
aoqi@0:     _method->code();
aoqi@0: 
aoqi@0:     _pos = 0;
aoqi@0:     _end = _method->_handler_count;
aoqi@0:     _exception_klass = NULL;
aoqi@0:     _bci    = -1;
aoqi@0:     _is_exact = false;
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciExceptionHandlerStream(ciMethod* method, int bci,
aoqi@0:                            ciInstanceKlass* exception_klass = NULL,
aoqi@0:                            bool is_exact = false) {
aoqi@0:     _method = method;
aoqi@0: 
aoqi@0:     // Force loading of method code and handlers.
aoqi@0:     _method->code();
aoqi@0: 
aoqi@0:     _pos = -1;
aoqi@0:     _end = _method->_handler_count + 1; // include the rethrow handler
aoqi@0:     _exception_klass = (exception_klass != NULL && exception_klass->is_loaded()
aoqi@0:                           ? exception_klass
aoqi@0:                           : NULL);
aoqi@0:     _bci = bci;
aoqi@0:     assert(_bci >= 0, "bci out of range");
aoqi@0:     _is_exact = is_exact;
aoqi@0:     next();
aoqi@0:   }
aoqi@0: 
aoqi@0:   // These methods are currently implemented in an odd way.
aoqi@0:   // Count the number of handlers the iterator has ever produced
aoqi@0:   // or will ever produce.  Do not include the final rethrow handler.
aoqi@0:   // That is, a trivial exception handler stream will have a count
aoqi@0:   // of zero and produce just the rethrow handler.
aoqi@0:   int count();
aoqi@0: 
aoqi@0:   // Count the number of handlers this stream will produce from now on.
aoqi@0:   // Include the current handler, and the final rethrow handler.
aoqi@0:   // The remaining count will be zero iff is_done() is true,
aoqi@0:   int count_remaining();
aoqi@0: 
aoqi@0:   bool is_done() {
aoqi@0:     return (_pos >= _end);
aoqi@0:   }
aoqi@0: 
aoqi@0:   void next() {
aoqi@0:     _pos++;
aoqi@0:     if (_bci != -1) {
aoqi@0:       // We are not iterating over all handlers...
aoqi@0:       while (!is_done()) {
aoqi@0:         ciExceptionHandler* handler = _method->_exception_handlers[_pos];
aoqi@0:         if (handler->is_in_range(_bci)) {
aoqi@0:           if (handler->is_catch_all()) {
aoqi@0:             // Found final active catch block.
aoqi@0:             _end = _pos+1;
aoqi@0:             return;
aoqi@0:           } else if (_exception_klass == NULL || !handler->catch_klass()->is_loaded()) {
aoqi@0:             // We cannot do any type analysis here.  Must conservatively assume
aoqi@0:             // catch block is reachable.
aoqi@0:             return;
aoqi@0:           } else if (_exception_klass->is_subtype_of(handler->catch_klass())) {
aoqi@0:             // This catch clause will definitely catch the exception.
aoqi@0:             // Final candidate.
aoqi@0:             _end = _pos+1;
aoqi@0:             return;
aoqi@0:           } else if (!_is_exact &&
aoqi@0:                      handler->catch_klass()->is_subtype_of(_exception_klass)) {
aoqi@0:             // This catch block may be reachable.
aoqi@0:             return;
aoqi@0:           }
aoqi@0:         }
aoqi@0: 
aoqi@0:         // The catch block was not pertinent.  Go on.
aoqi@0:         _pos++;
aoqi@0:       }
aoqi@0:     } else {
aoqi@0:       // This is an iteration over all handlers.
aoqi@0:       return;
aoqi@0:     }
aoqi@0:   }
aoqi@0: 
aoqi@0:   ciExceptionHandler* handler() {
aoqi@0:     return _method->_exception_handlers[_pos];
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: 
aoqi@0: 
aoqi@0: // Implementation for declarations in bytecode.hpp
aoqi@0: Bytecode::Bytecode(const ciBytecodeStream* stream, address bcp): _bcp(bcp != NULL ? bcp : stream->cur_bcp()), _code(Bytecodes::code_at(NULL, addr_at(0))) {}
aoqi@0: Bytecode_lookupswitch::Bytecode_lookupswitch(const ciBytecodeStream* stream): Bytecode(stream) { verify(); }
aoqi@0: Bytecode_tableswitch::Bytecode_tableswitch(const ciBytecodeStream* stream): Bytecode(stream) { verify(); }
aoqi@0: 
aoqi@0: #endif // SHARE_VM_CI_CISTREAMS_HPP