Mercurial > hg > truffle
view src/share/vm/code/compressedStream.hpp @ 18136:52b8826ef035
Backout wrong change in 2a69cbe850a8
author | Gilles Duboscq <duboscq@ssw.jku.at> |
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date | Tue, 21 Oct 2014 10:20:33 +0200 |
parents | f95d63e2154a |
children |
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/* * Copyright (c) 1997, 2010, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. * */ #ifndef SHARE_VM_CODE_COMPRESSEDSTREAM_HPP #define SHARE_VM_CODE_COMPRESSEDSTREAM_HPP #include "memory/allocation.hpp" // Simple interface for filing out and filing in basic types // Used for writing out and reading in debugging information. class CompressedStream : public ResourceObj { friend class VMStructs; protected: u_char* _buffer; int _position; enum { // Constants for UNSIGNED5 coding of Pack200 lg_H = 6, H = 1<<lg_H, // number of high codes (64) L = (1<<BitsPerByte)-H, // number of low codes (192) MAX_i = 4 // bytes are numbered in (0..4), max 5 bytes }; // these inlines are defined only in compressedStream.cpp static inline juint encode_sign(jint value); // for Pack200 SIGNED5 static inline jint decode_sign(juint value); // for Pack200 SIGNED5 static inline juint reverse_int(juint bits); // to trim trailing float 0's public: CompressedStream(u_char* buffer, int position = 0) { _buffer = buffer; _position = position; } u_char* buffer() const { return _buffer; } // Positioning int position() const { return _position; } void set_position(int position) { _position = position; } }; class CompressedReadStream : public CompressedStream { private: inline u_char read() { return _buffer[_position++]; } jint read_int_mb(jint b0); // UNSIGNED5 coding, 2-5 byte cases public: CompressedReadStream(u_char* buffer, int position = 0) : CompressedStream(buffer, position) {} jboolean read_bool() { return (jboolean) read(); } jbyte read_byte() { return (jbyte ) read(); } jchar read_char() { return (jchar ) read_int(); } jshort read_short() { return (jshort ) read_signed_int(); } jint read_int() { jint b0 = read(); if (b0 < L) return b0; else return read_int_mb(b0); } jint read_signed_int(); jfloat read_float(); // jfloat_cast(reverse_int(read_int())) jdouble read_double(); // jdouble_cast(2*reverse_int(read_int)) jlong read_long(); // jlong_from(2*read_signed_int()) }; class CompressedWriteStream : public CompressedStream { private: bool full() { return _position >= _size; } void store(u_char b) { _buffer[_position++] = b; } void write(u_char b) { if (full()) grow(); store(b); } void grow(); void write_int_mb(jint value); // UNSIGNED5 coding, 1-5 byte cases protected: int _size; public: CompressedWriteStream(int initial_size); CompressedWriteStream(u_char* buffer, int initial_size, int position = 0) : CompressedStream(buffer, position) { _size = initial_size; } void write_bool(jboolean value) { write(value); } void write_byte(jbyte value) { write(value); } void write_char(jchar value) { write_int(value); } void write_short(jshort value) { write_signed_int(value); } void write_int(jint value) { if ((juint)value < L && !full()) store((u_char)value); else write_int_mb(value); } void write_signed_int(jint value); // write_int(encode_sign(value)) void write_float(jfloat value); // write_int(reverse_int(jint_cast(v))) void write_double(jdouble value); // write_int(reverse_int(<low,high>)) void write_long(jlong value); // write_signed_int(<low,high>) }; #endif // SHARE_VM_CODE_COMPRESSEDSTREAM_HPP