src/share/vm/code/compressedStream.hpp

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   1 /*
   2  * Copyright (c) 1997, 2005, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 





  25 // Simple interface for filing out and filing in basic types
  26 // Used for writing out and reading in debugging information.
  27 
  28 class CompressedStream : public ResourceObj {
  29   friend class VMStructs;
  30  protected:
  31   u_char* _buffer;
  32   int     _position;
  33 
  34   enum {
  35     // Constants for UNSIGNED5 coding of Pack200
  36     lg_H = 6, H = 1<<lg_H,    // number of high codes (64)
  37     L = (1<<BitsPerByte)-H,   // number of low codes (192)
  38     MAX_i = 4                 // bytes are numbered in (0..4), max 5 bytes
  39   };
  40 
  41   // these inlines are defined only in compressedStream.cpp
  42   static inline juint encode_sign(jint  value);  // for Pack200 SIGNED5
  43   static inline jint  decode_sign(juint value);  // for Pack200 SIGNED5
  44   static inline juint reverse_int(juint bits);   // to trim trailing float 0's


 101  protected:
 102   int _size;
 103 
 104  public:
 105   CompressedWriteStream(int initial_size);
 106   CompressedWriteStream(u_char* buffer, int initial_size, int position = 0)
 107   : CompressedStream(buffer, position) { _size = initial_size; }
 108 
 109   void write_bool(jboolean value)      { write(value);      }
 110   void write_byte(jbyte value)         { write(value);      }
 111   void write_char(jchar value)         { write_int(value); }
 112   void write_short(jshort value)       { write_signed_int(value);  }
 113   void write_int(jint value)           { if ((juint)value < L && !full())
 114                                                store((u_char)value);
 115                                          else  write_int_mb(value);  }
 116   void write_signed_int(jint value);   // write_int(encode_sign(value))
 117   void write_float(jfloat value);      // write_int(reverse_int(jint_cast(v)))
 118   void write_double(jdouble value);    // write_int(reverse_int(<low,high>))
 119   void write_long(jlong value);        // write_signed_int(<low,high>)
 120 };


   1 /*
   2  * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_CODE_COMPRESSEDSTREAM_HPP
  26 #define SHARE_VM_CODE_COMPRESSEDSTREAM_HPP
  27 
  28 #include "memory/allocation.hpp"
  29 
  30 // Simple interface for filing out and filing in basic types
  31 // Used for writing out and reading in debugging information.
  32 
  33 class CompressedStream : public ResourceObj {
  34   friend class VMStructs;
  35  protected:
  36   u_char* _buffer;
  37   int     _position;
  38 
  39   enum {
  40     // Constants for UNSIGNED5 coding of Pack200
  41     lg_H = 6, H = 1<<lg_H,    // number of high codes (64)
  42     L = (1<<BitsPerByte)-H,   // number of low codes (192)
  43     MAX_i = 4                 // bytes are numbered in (0..4), max 5 bytes
  44   };
  45 
  46   // these inlines are defined only in compressedStream.cpp
  47   static inline juint encode_sign(jint  value);  // for Pack200 SIGNED5
  48   static inline jint  decode_sign(juint value);  // for Pack200 SIGNED5
  49   static inline juint reverse_int(juint bits);   // to trim trailing float 0's


 106  protected:
 107   int _size;
 108 
 109  public:
 110   CompressedWriteStream(int initial_size);
 111   CompressedWriteStream(u_char* buffer, int initial_size, int position = 0)
 112   : CompressedStream(buffer, position) { _size = initial_size; }
 113 
 114   void write_bool(jboolean value)      { write(value);      }
 115   void write_byte(jbyte value)         { write(value);      }
 116   void write_char(jchar value)         { write_int(value); }
 117   void write_short(jshort value)       { write_signed_int(value);  }
 118   void write_int(jint value)           { if ((juint)value < L && !full())
 119                                                store((u_char)value);
 120                                          else  write_int_mb(value);  }
 121   void write_signed_int(jint value);   // write_int(encode_sign(value))
 122   void write_float(jfloat value);      // write_int(reverse_int(jint_cast(v)))
 123   void write_double(jdouble value);    // write_int(reverse_int(<low,high>))
 124   void write_long(jlong value);        // write_signed_int(<low,high>)
 125 };
 126 
 127 #endif // SHARE_VM_CODE_COMPRESSEDSTREAM_HPP