duke@435: /*
never@2462:  * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #ifndef SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP
stefank@2314: #define SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP
stefank@2314: 
stefank@2314: #include "interpreter/bytecode.hpp"
stefank@2314: #include "memory/allocation.hpp"
stefank@2314: #include "oops/methodOop.hpp"
stefank@2314: #ifdef TARGET_ARCH_x86
stefank@2314: # include "bytes_x86.hpp"
stefank@2314: #endif
stefank@2314: #ifdef TARGET_ARCH_sparc
stefank@2314: # include "bytes_sparc.hpp"
stefank@2314: #endif
stefank@2314: #ifdef TARGET_ARCH_zero
stefank@2314: # include "bytes_zero.hpp"
stefank@2314: #endif
bobv@2508: #ifdef TARGET_ARCH_arm
bobv@2508: # include "bytes_arm.hpp"
bobv@2508: #endif
bobv@2508: #ifdef TARGET_ARCH_ppc
bobv@2508: # include "bytes_ppc.hpp"
bobv@2508: #endif
stefank@2314: 
duke@435: // A BytecodeStream is used for fast iteration over the bytecodes
duke@435: // of a methodOop.
duke@435: //
duke@435: // Usage:
duke@435: //
duke@435: // BytecodeStream s(method);
duke@435: // Bytecodes::Code c;
duke@435: // while ((c = s.next()) >= 0) {
duke@435: //   ...
duke@435: // }
jrose@1920: 
duke@435: // A RawBytecodeStream is a simple version of BytecodeStream.
duke@435: // It is used ONLY when we know the bytecodes haven't been rewritten
jrose@1920: // yet, such as in the rewriter or the verifier.
duke@435: 
jrose@1920: // Here is the common base class for both RawBytecodeStream and BytecodeStream:
jrose@1920: class BaseBytecodeStream: StackObj {
duke@435:  protected:
duke@435:   // stream buffer
duke@435:   methodHandle    _method;                       // read from method directly
duke@435: 
duke@435:   // reading position
duke@435:   int             _bci;                          // bci if current bytecode
duke@435:   int             _next_bci;                     // bci of next bytecode
duke@435:   int             _end_bci;                      // bci after the current iteration interval
duke@435: 
duke@435:   // last bytecode read
jrose@1920:   Bytecodes::Code _raw_code;
duke@435:   bool            _is_wide;
jrose@1920:   bool            _is_raw;                       // false in 'cooked' BytecodeStream
jrose@1920: 
jrose@1920:   // Construction
jrose@1920:   BaseBytecodeStream(methodHandle method) : _method(method) {
jrose@1920:     set_interval(0, _method->code_size());
jrose@1920:     _is_raw = false;
jrose@1920:   }
duke@435: 
duke@435:  public:
duke@435:   // Iteration control
duke@435:   void set_interval(int beg_bci, int end_bci) {
duke@435:     // iterate over the interval [beg_bci, end_bci)
duke@435:     assert(0 <= beg_bci && beg_bci <= method()->code_size(), "illegal beg_bci");
duke@435:     assert(0 <= end_bci && end_bci <= method()->code_size(), "illegal end_bci");
duke@435:     // setup of iteration pointers
duke@435:     _bci      = beg_bci;
duke@435:     _next_bci = beg_bci;
duke@435:     _end_bci  = end_bci;
duke@435:   }
duke@435:   void set_start   (int beg_bci) {
duke@435:     set_interval(beg_bci, _method->code_size());
duke@435:   }
duke@435: 
jrose@1920:   bool is_raw() const { return _is_raw; }
jrose@1920: 
jrose@1920:   // Stream attributes
jrose@1920:   methodHandle    method() const                 { return _method; }
jrose@1920: 
jrose@1920:   int             bci() const                    { return _bci; }
jrose@1920:   int             next_bci() const               { return _next_bci; }
jrose@1920:   int             end_bci() const                { return _end_bci; }
jrose@1920: 
jrose@1920:   Bytecodes::Code raw_code() const               { return _raw_code; }
jrose@1920:   bool            is_wide() const                { return _is_wide; }
jrose@1920:   int             instruction_size() const       { return (_next_bci - _bci); }
jrose@1920:   bool            is_last_bytecode() const       { return _next_bci >= _end_bci; }
jrose@1920: 
jrose@1920:   address         bcp() const                    { return method()->code_base() + _bci; }
never@2462:   Bytecode        bytecode() const               { return Bytecode(_method(), bcp()); }
jrose@1920: 
jrose@1920:   // State changes
jrose@1920:   void            set_next_bci(int bci)          { assert(0 <= bci && bci <= method()->code_size(), "illegal bci"); _next_bci = bci; }
jrose@1920: 
jrose@1920:   // Bytecode-specific attributes
never@2462:   int             dest() const                   { return bci() + bytecode().get_offset_s2(raw_code()); }
never@2462:   int             dest_w() const                 { return bci() + bytecode().get_offset_s4(raw_code()); }
jrose@1920: 
jrose@1920:   // One-byte indices.
jrose@1920:   int             get_index_u1() const           { assert_raw_index_size(1); return *(jubyte*)(bcp()+1); }
jrose@1920: 
jrose@1920:  protected:
jrose@1920:   void assert_raw_index_size(int size) const NOT_DEBUG_RETURN;
jrose@1920:   void assert_raw_stream(bool want_raw) const NOT_DEBUG_RETURN;
jrose@1920: };
jrose@1920: 
jrose@1920: class RawBytecodeStream: public BaseBytecodeStream {
jrose@1920:  public:
jrose@1920:   // Construction
jrose@1920:   RawBytecodeStream(methodHandle method) : BaseBytecodeStream(method) {
jrose@1920:     _is_raw = true;
jrose@1920:   }
jrose@1920: 
jrose@1920:  public:
duke@435:   // Iteration
duke@435:   // Use raw_next() rather than next() for faster method reference
duke@435:   Bytecodes::Code raw_next() {
duke@435:     Bytecodes::Code code;
duke@435:     // set reading position
duke@435:     _bci = _next_bci;
duke@435:     assert(!is_last_bytecode(), "caller should check is_last_bytecode()");
duke@435: 
jrose@1920:     address bcp = this->bcp();
duke@435:     code        = Bytecodes::code_or_bp_at(bcp);
duke@435: 
duke@435:     // set next bytecode position
duke@435:     int l = Bytecodes::length_for(code);
duke@435:     if (l > 0 && (_bci + l) <= _end_bci) {
duke@435:       assert(code != Bytecodes::_wide && code != Bytecodes::_tableswitch
duke@435:              && code != Bytecodes::_lookupswitch, "can't be special bytecode");
duke@435:       _is_wide = false;
duke@435:       _next_bci += l;
jrose@1920:       _raw_code = code;
duke@435:       return code;
duke@435:     } else {
duke@435:       return raw_next_special(code);
duke@435:     }
duke@435:   }
duke@435:   Bytecodes::Code raw_next_special(Bytecodes::Code code);
duke@435: 
jrose@1920:   // Unsigned indices, widening, with no swapping of bytes
jrose@1920:   int             get_index() const          { return (is_wide()) ? get_index_u2_raw(bcp() + 2) : get_index_u1(); }
jrose@1920:   // Get an unsigned 2-byte index, with no swapping of bytes.
jrose@1920:   int             get_index_u2() const       { assert(!is_wide(), ""); return get_index_u2_raw(bcp() + 1);  }
jrose@1161: 
jrose@1161:  private:
jrose@1920:   int get_index_u2_raw(address p) const {
jrose@1920:     assert_raw_index_size(2); assert_raw_stream(true);
jrose@1920:     return Bytes::get_Java_u2(p);
jrose@1161:   }
duke@435: };
duke@435: 
duke@435: // In BytecodeStream, non-java bytecodes will be translated into the
duke@435: // corresponding java bytecodes.
duke@435: 
jrose@1920: class BytecodeStream: public BaseBytecodeStream {
jrose@1920:   Bytecodes::Code _code;
jrose@1920: 
duke@435:  public:
duke@435:   // Construction
jrose@1920:   BytecodeStream(methodHandle method) : BaseBytecodeStream(method) { }
duke@435: 
duke@435:   // Iteration
duke@435:   Bytecodes::Code next() {
jrose@1920:     Bytecodes::Code raw_code, code;
duke@435:     // set reading position
duke@435:     _bci = _next_bci;
duke@435:     if (is_last_bytecode()) {
duke@435:       // indicate end of bytecode stream
jrose@1920:       raw_code = code = Bytecodes::_illegal;
duke@435:     } else {
duke@435:       // get bytecode
jrose@1920:       address bcp = this->bcp();
never@2462:       raw_code = Bytecodes::code_at(_method(), bcp);
jrose@1920:       code = Bytecodes::java_code(raw_code);
duke@435:       // set next bytecode position
duke@435:       //
duke@435:       // note that we cannot advance before having the
duke@435:       // tty bytecode otherwise the stepping is wrong!
duke@435:       // (carefull: length_for(...) must be used first!)
duke@435:       int l = Bytecodes::length_for(code);
never@2462:       if (l == 0) l = Bytecodes::length_at(_method(), bcp);
duke@435:       _next_bci  += l;
duke@435:       assert(_bci < _next_bci, "length must be > 0");
duke@435:       // set attributes
duke@435:       _is_wide      = false;
duke@435:       // check for special (uncommon) cases
duke@435:       if (code == Bytecodes::_wide) {
jrose@1920:         raw_code = (Bytecodes::Code)bcp[1];
jrose@1920:         code = raw_code;  // wide BCs are always Java-normal
duke@435:         _is_wide = true;
duke@435:       }
duke@435:       assert(Bytecodes::is_java_code(code), "sanity check");
duke@435:     }
jrose@1920:     _raw_code = raw_code;
duke@435:     _code = code;
duke@435:     return _code;
duke@435:   }
duke@435: 
duke@435:   bool            is_active_breakpoint() const   { return Bytecodes::is_active_breakpoint_at(bcp()); }
jrose@1920:   Bytecodes::Code code() const                   { return _code; }
jrose@1920: 
jrose@1920:   // Unsigned indices, widening
never@2462:   int             get_index() const              { return is_wide() ? bytecode().get_index_u2(raw_code(), true) : get_index_u1(); }
jrose@1920:   // Get an unsigned 2-byte index, swapping the bytes if necessary.
jrose@1920:   int             get_index_u2() const           { assert_raw_stream(false);
never@2462:                                                    return bytecode().get_index_u2(raw_code(), false); }
jrose@1920:   // Get an unsigned 2-byte index in native order.
jrose@1920:   int             get_index_u2_cpcache() const   { assert_raw_stream(false);
never@2462:                                                    return bytecode().get_index_u2_cpcache(raw_code()); }
jrose@1920:   int             get_index_u4() const           { assert_raw_stream(false);
never@2462:                                                    return bytecode().get_index_u4(raw_code()); }
never@2462:   bool            has_index_u4() const           { return bytecode().has_index_u4(raw_code()); }
duke@435: };
stefank@2314: 
stefank@2314: #endif // SHARE_VM_INTERPRETER_BYTECODESTREAM_HPP