aoqi@0: /*
aoqi@0:  * Copyright (c) 1997, 2012, 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_INTERPRETER_BYTECODESTREAM_HPP
aoqi@0: #define SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP
aoqi@0: 
aoqi@0: #include "interpreter/bytecode.hpp"
aoqi@0: #include "memory/allocation.hpp"
aoqi@0: #include "oops/method.hpp"
aoqi@0: #include "runtime/handles.inline.hpp"
aoqi@0: #ifdef TARGET_ARCH_x86
aoqi@0: # include "bytes_x86.hpp"
aoqi@0: #endif
aoqi@0: #ifdef TARGET_ARCH_sparc
aoqi@0: # include "bytes_sparc.hpp"
aoqi@0: #endif
aoqi@0: #ifdef TARGET_ARCH_zero
aoqi@0: # include "bytes_zero.hpp"
aoqi@0: #endif
aoqi@0: #ifdef TARGET_ARCH_arm
aoqi@0: # include "bytes_arm.hpp"
aoqi@0: #endif
aoqi@0: #ifdef TARGET_ARCH_ppc
aoqi@0: # include "bytes_ppc.hpp"
aoqi@0: #endif
aoqi@0: 
aoqi@0: // A BytecodeStream is used for fast iteration over the bytecodes
aoqi@0: // of a Method*.
aoqi@0: //
aoqi@0: // Usage:
aoqi@0: //
aoqi@0: // BytecodeStream s(method);
aoqi@0: // Bytecodes::Code c;
aoqi@0: // while ((c = s.next()) >= 0) {
aoqi@0: //   ...
aoqi@0: // }
aoqi@0: 
aoqi@0: // A RawBytecodeStream is a simple version of BytecodeStream.
aoqi@0: // It is used ONLY when we know the bytecodes haven't been rewritten
aoqi@0: // yet, such as in the rewriter or the verifier.
aoqi@0: 
aoqi@0: // Here is the common base class for both RawBytecodeStream and BytecodeStream:
aoqi@0: class BaseBytecodeStream: StackObj {
aoqi@0:  protected:
aoqi@0:   // stream buffer
aoqi@0:   methodHandle    _method;                       // read from method directly
aoqi@0: 
aoqi@0:   // reading position
aoqi@0:   int             _bci;                          // bci if current bytecode
aoqi@0:   int             _next_bci;                     // bci of next bytecode
aoqi@0:   int             _end_bci;                      // bci after the current iteration interval
aoqi@0: 
aoqi@0:   // last bytecode read
aoqi@0:   Bytecodes::Code _raw_code;
aoqi@0:   bool            _is_wide;
aoqi@0:   bool            _is_raw;                       // false in 'cooked' BytecodeStream
aoqi@0: 
aoqi@0:   // Construction
aoqi@0:   BaseBytecodeStream(methodHandle method) : _method(method) {
aoqi@0:     set_interval(0, _method->code_size());
aoqi@0:     _is_raw = false;
aoqi@0:   }
aoqi@0: 
aoqi@0:  public:
aoqi@0:   // Iteration control
aoqi@0:   void set_interval(int beg_bci, int end_bci) {
aoqi@0:     // iterate over the interval [beg_bci, end_bci)
aoqi@0:     assert(0 <= beg_bci && beg_bci <= method()->code_size(), "illegal beg_bci");
aoqi@0:     assert(0 <= end_bci && end_bci <= method()->code_size(), "illegal end_bci");
aoqi@0:     // setup of iteration pointers
aoqi@0:     _bci      = beg_bci;
aoqi@0:     _next_bci = beg_bci;
aoqi@0:     _end_bci  = end_bci;
aoqi@0:   }
aoqi@0:   void set_start   (int beg_bci) {
aoqi@0:     set_interval(beg_bci, _method->code_size());
aoqi@0:   }
aoqi@0: 
aoqi@0:   bool is_raw() const { return _is_raw; }
aoqi@0: 
aoqi@0:   // Stream attributes
aoqi@0:   methodHandle    method() const                 { return _method; }
aoqi@0: 
aoqi@0:   int             bci() const                    { return _bci; }
aoqi@0:   int             next_bci() const               { return _next_bci; }
aoqi@0:   int             end_bci() const                { return _end_bci; }
aoqi@0: 
aoqi@0:   Bytecodes::Code raw_code() const               { return _raw_code; }
aoqi@0:   bool            is_wide() const                { return _is_wide; }
aoqi@0:   int             instruction_size() const       { return (_next_bci - _bci); }
aoqi@0:   bool            is_last_bytecode() const       { return _next_bci >= _end_bci; }
aoqi@0: 
aoqi@0:   address         bcp() const                    { return method()->code_base() + _bci; }
aoqi@0:   Bytecode        bytecode() const               { return Bytecode(_method(), bcp()); }
aoqi@0: 
aoqi@0:   // State changes
aoqi@0:   void            set_next_bci(int bci)          { assert(0 <= bci && bci <= method()->code_size(), "illegal bci"); _next_bci = bci; }
aoqi@0: 
aoqi@0:   // Bytecode-specific attributes
aoqi@0:   int             dest() const                   { return bci() + bytecode().get_offset_s2(raw_code()); }
aoqi@0:   int             dest_w() const                 { return bci() + bytecode().get_offset_s4(raw_code()); }
aoqi@0: 
aoqi@0:   // One-byte indices.
aoqi@0:   int             get_index_u1() const           { assert_raw_index_size(1); return *(jubyte*)(bcp()+1); }
aoqi@0: 
aoqi@0:  protected:
aoqi@0:   void assert_raw_index_size(int size) const NOT_DEBUG_RETURN;
aoqi@0:   void assert_raw_stream(bool want_raw) const NOT_DEBUG_RETURN;
aoqi@0: };
aoqi@0: 
aoqi@0: class RawBytecodeStream: public BaseBytecodeStream {
aoqi@0:  public:
aoqi@0:   // Construction
aoqi@0:   RawBytecodeStream(methodHandle method) : BaseBytecodeStream(method) {
aoqi@0:     _is_raw = true;
aoqi@0:   }
aoqi@0: 
aoqi@0:  public:
aoqi@0:   // Iteration
aoqi@0:   // Use raw_next() rather than next() for faster method reference
aoqi@0:   Bytecodes::Code raw_next() {
aoqi@0:     Bytecodes::Code code;
aoqi@0:     // set reading position
aoqi@0:     _bci = _next_bci;
aoqi@0:     assert(!is_last_bytecode(), "caller should check is_last_bytecode()");
aoqi@0: 
aoqi@0:     address bcp = this->bcp();
aoqi@0:     code        = Bytecodes::code_or_bp_at(bcp);
aoqi@0: 
aoqi@0:     // set next bytecode position
aoqi@0:     int l = Bytecodes::length_for(code);
aoqi@0:     if (l > 0 && (_bci + l) <= _end_bci) {
aoqi@0:       assert(code != Bytecodes::_wide && code != Bytecodes::_tableswitch
aoqi@0:              && code != Bytecodes::_lookupswitch, "can't be special bytecode");
aoqi@0:       _is_wide = false;
aoqi@0:       _next_bci += l;
aoqi@0:       _raw_code = code;
aoqi@0:       return code;
aoqi@0:     } else {
aoqi@0:       return raw_next_special(code);
aoqi@0:     }
aoqi@0:   }
aoqi@0:   Bytecodes::Code raw_next_special(Bytecodes::Code code);
aoqi@0: 
aoqi@0:   // Unsigned indices, widening, with no swapping of bytes
aoqi@0:   int             get_index() const          { return (is_wide()) ? get_index_u2_raw(bcp() + 2) : get_index_u1(); }
aoqi@0:   // Get an unsigned 2-byte index, with no swapping of bytes.
aoqi@0:   int             get_index_u2() const       { assert(!is_wide(), ""); return get_index_u2_raw(bcp() + 1);  }
aoqi@0: 
aoqi@0:  private:
aoqi@0:   int get_index_u2_raw(address p) const {
aoqi@0:     assert_raw_index_size(2); assert_raw_stream(true);
aoqi@0:     return Bytes::get_Java_u2(p);
aoqi@0:   }
aoqi@0: };
aoqi@0: 
aoqi@0: // In BytecodeStream, non-java bytecodes will be translated into the
aoqi@0: // corresponding java bytecodes.
aoqi@0: 
aoqi@0: class BytecodeStream: public BaseBytecodeStream {
aoqi@0:   Bytecodes::Code _code;
aoqi@0: 
aoqi@0:  public:
aoqi@0:   // Construction
aoqi@0:   BytecodeStream(methodHandle method) : BaseBytecodeStream(method) { }
aoqi@0: 
aoqi@0:   // Iteration
aoqi@0:   Bytecodes::Code next() {
aoqi@0:     Bytecodes::Code raw_code, code;
aoqi@0:     // set reading position
aoqi@0:     _bci = _next_bci;
aoqi@0:     if (is_last_bytecode()) {
aoqi@0:       // indicate end of bytecode stream
aoqi@0:       raw_code = code = Bytecodes::_illegal;
aoqi@0:     } else {
aoqi@0:       // get bytecode
aoqi@0:       address bcp = this->bcp();
aoqi@0:       raw_code = Bytecodes::code_at(_method(), bcp);
aoqi@0:       code = Bytecodes::java_code(raw_code);
aoqi@0:       // set next bytecode position
aoqi@0:       //
aoqi@0:       // note that we cannot advance before having the
aoqi@0:       // tty bytecode otherwise the stepping is wrong!
aoqi@0:       // (carefull: length_for(...) must be used first!)
aoqi@0:       int l = Bytecodes::length_for(code);
aoqi@0:       if (l == 0) l = Bytecodes::length_at(_method(), bcp);
aoqi@0:       _next_bci  += l;
aoqi@0:       assert(_bci < _next_bci, "length must be > 0");
aoqi@0:       // set attributes
aoqi@0:       _is_wide      = false;
aoqi@0:       // check for special (uncommon) cases
aoqi@0:       if (code == Bytecodes::_wide) {
aoqi@0:         raw_code = (Bytecodes::Code)bcp[1];
aoqi@0:         code = raw_code;  // wide BCs are always Java-normal
aoqi@0:         _is_wide = true;
aoqi@0:       }
aoqi@0:       assert(Bytecodes::is_java_code(code), "sanity check");
aoqi@0:     }
aoqi@0:     _raw_code = raw_code;
aoqi@0:     _code = code;
aoqi@0:     return _code;
aoqi@0:   }
aoqi@0: 
aoqi@0:   bool            is_active_breakpoint() const   { return Bytecodes::is_active_breakpoint_at(bcp()); }
aoqi@0:   Bytecodes::Code code() const                   { return _code; }
aoqi@0: 
aoqi@0:   // Unsigned indices, widening
aoqi@0:   int             get_index() const              { return is_wide() ? bytecode().get_index_u2(raw_code(), true) : get_index_u1(); }
aoqi@0:   // Get an unsigned 2-byte index, swapping the bytes if necessary.
aoqi@0:   int             get_index_u2() const           { assert_raw_stream(false);
aoqi@0:                                                    return bytecode().get_index_u2(raw_code(), false); }
aoqi@0:   // Get an unsigned 2-byte index in native order.
aoqi@0:   int             get_index_u2_cpcache() const   { assert_raw_stream(false);
aoqi@0:                                                    return bytecode().get_index_u2_cpcache(raw_code()); }
aoqi@0:   int             get_index_u4() const           { assert_raw_stream(false);
aoqi@0:                                                    return bytecode().get_index_u4(raw_code()); }
aoqi@0:   bool            has_index_u4() const           { return bytecode().has_index_u4(raw_code()); }
aoqi@0: };
aoqi@0: 
aoqi@0: #endif // SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP