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| author | Willem Jan Palenstijn | 2017-07-24 21:01:19 +0200 |
|---|---|---|
| committer | Willem Jan Palenstijn | 2017-08-24 19:46:59 +0200 |
| commit | dde259f06813534c7179a714403d8fd6fe918d09 (patch) | |
| tree | 1379a5c2600057ba53032c722e3a5a1578db8507 /common | |
| parent | 265fc48d1590cdd503187c79dc254d65623c8d7b (diff) | |
| download | scummvm-rg350-dde259f06813534c7179a714403d8fd6fe918d09.tar.gz scummvm-rg350-dde259f06813534c7179a714403d8fd6fe918d09.tar.bz2 scummvm-rg350-dde259f06813534c7179a714403d8fd6fe918d09.zip | |
COMMON: Remove BitStream base class to allow inlining calls
All users of BitStream were in fact using a specific, hardcoded variant,
so we can hardcode that variant, removing the need for virtual calls,
and enabling inlining.
Diffstat (limited to 'common')
| -rw-r--r-- | common/bitstream.h | 74 | ||||
| -rw-r--r-- | common/huffman.cpp | 15 | ||||
| -rw-r--r-- | common/huffman.h | 18 |
3 files changed, 30 insertions, 77 deletions
diff --git a/common/bitstream.h b/common/bitstream.h index 325118bbee..ae5677da1a 100644 --- a/common/bitstream.h +++ b/common/bitstream.h @@ -32,50 +32,6 @@ namespace Common { -/** A bit stream. */ -class BitStream { -public: - virtual ~BitStream() { - } - - /** Return the stream position in bits. */ - virtual uint32 pos() const = 0; - - /** Return the stream size in bits. */ - virtual uint32 size() const = 0; - - /** Has the end of the stream been reached? */ - virtual bool eos() const = 0; - - /** Rewind the bit stream back to the start. */ - virtual void rewind() = 0; - - /** Skip the specified amount of bits. */ - virtual void skip(uint32 n) = 0; - - /** Skip the bits to closest data value border. */ - virtual void align() = 0; - - /** Read a bit from the bit stream. */ - virtual uint32 getBit() = 0; - - /** Read a multi-bit value from the bit stream. */ - virtual uint32 getBits(uint8 n) = 0; - - /** Read a bit from the bit stream, without changing the stream's position. */ - virtual uint32 peekBit() = 0; - - /** Read a multi-bit value from the bit stream, without changing the stream's position. */ - virtual uint32 peekBits(uint8 n) = 0; - - /** Add a bit to the value x, making it an n+1-bit value. */ - virtual void addBit(uint32 &x, uint32 n) = 0; - -protected: - BitStream() { - } -}; - /** * A template implementing a bit stream for different data memory layouts. * @@ -86,10 +42,10 @@ protected: * for valueBits, isLE and isMSB2LSB, reads 32bit little-endian values * from the data stream and hands out the bits in the order of LSB to MSB. */ -template<int valueBits, bool isLE, bool isMSB2LSB> -class BitStreamImpl : public BitStream { +template<class STREAM, int valueBits, bool isLE, bool isMSB2LSB> +class BitStreamImpl { private: - SeekableReadStream *_stream; ///< The input stream. + STREAM *_stream; ///< The input stream. DisposeAfterUse::Flag _disposeAfterUse; ///< Should we delete the stream on destruction? uint32 _value; ///< Current value. @@ -133,7 +89,7 @@ private: public: /** Create a bit stream using this input data stream and optionally delete it on destruction. */ - BitStreamImpl(SeekableReadStream *stream, DisposeAfterUse::Flag disposeAfterUse = DisposeAfterUse::NO) : + BitStreamImpl(STREAM *stream, DisposeAfterUse::Flag disposeAfterUse = DisposeAfterUse::NO) : _stream(stream), _disposeAfterUse(disposeAfterUse), _value(0), _inValue(0) { if ((valueBits != 8) && (valueBits != 16) && (valueBits != 32)) @@ -141,7 +97,7 @@ public: } /** Create a bit stream using this input data stream. */ - BitStreamImpl(SeekableReadStream &stream) : + BitStreamImpl(STREAM &stream) : _stream(&stream), _disposeAfterUse(DisposeAfterUse::NO), _value(0), _inValue(0) { if ((valueBits != 8) && (valueBits != 16) && (valueBits != 32)) @@ -308,27 +264,27 @@ public: // typedefs for various memory layouts. /** 8-bit data, MSB to LSB. */ -typedef BitStreamImpl<8, false, true > BitStream8MSB; +typedef BitStreamImpl<SeekableReadStream, 8, false, true > BitStream8MSB; /** 8-bit data, LSB to MSB. */ -typedef BitStreamImpl<8, false, false> BitStream8LSB; +typedef BitStreamImpl<SeekableReadStream, 8, false, false> BitStream8LSB; /** 16-bit little-endian data, MSB to LSB. */ -typedef BitStreamImpl<16, true , true > BitStream16LEMSB; +typedef BitStreamImpl<SeekableReadStream, 16, true , true > BitStream16LEMSB; /** 16-bit little-endian data, LSB to MSB. */ -typedef BitStreamImpl<16, true , false> BitStream16LELSB; +typedef BitStreamImpl<SeekableReadStream, 16, true , false> BitStream16LELSB; /** 16-bit big-endian data, MSB to LSB. */ -typedef BitStreamImpl<16, false, true > BitStream16BEMSB; +typedef BitStreamImpl<SeekableReadStream, 16, false, true > BitStream16BEMSB; /** 16-bit big-endian data, LSB to MSB. */ -typedef BitStreamImpl<16, false, false> BitStream16BELSB; +typedef BitStreamImpl<SeekableReadStream, 16, false, false> BitStream16BELSB; /** 32-bit little-endian data, MSB to LSB. */ -typedef BitStreamImpl<32, true , true > BitStream32LEMSB; +typedef BitStreamImpl<SeekableReadStream, 32, true , true > BitStream32LEMSB; /** 32-bit little-endian data, LSB to MSB. */ -typedef BitStreamImpl<32, true , false> BitStream32LELSB; +typedef BitStreamImpl<SeekableReadStream, 32, true , false> BitStream32LELSB; /** 32-bit big-endian data, MSB to LSB. */ -typedef BitStreamImpl<32, false, true > BitStream32BEMSB; +typedef BitStreamImpl<SeekableReadStream, 32, false, true > BitStream32BEMSB; /** 32-bit big-endian data, LSB to MSB. */ -typedef BitStreamImpl<32, false, false> BitStream32BELSB; +typedef BitStreamImpl<SeekableReadStream, 32, false, false> BitStream32BELSB; } // End of namespace Common diff --git a/common/huffman.cpp b/common/huffman.cpp index afb4fa00b6..3268ddf251 100644 --- a/common/huffman.cpp +++ b/common/huffman.cpp @@ -68,19 +68,4 @@ void Huffman::setSymbols(const uint32 *symbols) { _symbols[i]->symbol = symbols ? *symbols++ : i; } -uint32 Huffman::getSymbol(BitStream &bits) const { - uint32 code = 0; - - for (uint32 i = 0; i < _codes.size(); i++) { - bits.addBit(code, i); - - for (CodeList::const_iterator cCode = _codes[i].begin(); cCode != _codes[i].end(); ++cCode) - if (code == cCode->code) - return cCode->symbol; - } - - error("Unknown Huffman code"); - return 0; -} - } // End of namespace Common diff --git a/common/huffman.h b/common/huffman.h index 5ba7deca87..f703d078dc 100644 --- a/common/huffman.h +++ b/common/huffman.h @@ -31,8 +31,6 @@ namespace Common { -class BitStream; - /** * Huffman bitstream decoding * @@ -56,7 +54,21 @@ public: void setSymbols(const uint32 *symbols = 0); /** Return the next symbol in the bitstream. */ - uint32 getSymbol(BitStream &bits) const; + template<class BITSTREAM> + uint32 getSymbol(BITSTREAM &bits) const { + uint32 code = 0; + + for (uint32 i = 0; i < _codes.size(); i++) { + bits.addBit(code, i); + + for (CodeList::const_iterator cCode = _codes[i].begin(); cCode != _codes[i].end(); ++cCode) + if (code == cCode->code) + return cCode->symbol; + } + + error("Unknown Huffman code"); + return 0; + } private: struct Symbol { |