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author | mm <mm@FreeBSD.org> | 2010-05-10 06:59:50 +0000 |
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committer | mm <mm@FreeBSD.org> | 2010-05-10 06:59:50 +0000 |
commit | 5c358d45429b654efa9c8177ecd370a7965ec1a7 (patch) | |
tree | d2d916954c6a66a3168ee356b5f24da01c2017d6 /contrib/xz/src/liblzma/rangecoder/price.h | |
parent | 3e09decd1986826f54af1a47be97bb87c1220783 (diff) | |
parent | 1008b7c6744a190c5b15aaf8cab1054671e4c7c3 (diff) | |
download | FreeBSD-src-5c358d45429b654efa9c8177ecd370a7965ec1a7.zip FreeBSD-src-5c358d45429b654efa9c8177ecd370a7965ec1a7.tar.gz |
Import of liblzma, xz, xzdec, lzmainfo from vendor branch
Add support for xz and lzma to lesspipe.sh (xzless, lzless)
Bump __FreeBSD_version
Approved by: delphij (mentor)
MFC after: 2 weeks
Diffstat (limited to 'contrib/xz/src/liblzma/rangecoder/price.h')
-rw-r--r-- | contrib/xz/src/liblzma/rangecoder/price.h | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/contrib/xz/src/liblzma/rangecoder/price.h b/contrib/xz/src/liblzma/rangecoder/price.h new file mode 100644 index 0000000..8ae02ca --- /dev/null +++ b/contrib/xz/src/liblzma/rangecoder/price.h @@ -0,0 +1,92 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file price.h +/// \brief Probability price calculation +// +// Author: Igor Pavlov +// +// This file has been put into the public domain. +// You can do whatever you want with this file. +// +/////////////////////////////////////////////////////////////////////////////// + +#ifndef LZMA_PRICE_H +#define LZMA_PRICE_H + + +#define RC_MOVE_REDUCING_BITS 4 +#define RC_BIT_PRICE_SHIFT_BITS 4 +#define RC_PRICE_TABLE_SIZE (RC_BIT_MODEL_TOTAL >> RC_MOVE_REDUCING_BITS) + +#define RC_INFINITY_PRICE (UINT32_C(1) << 30) + + +/// Lookup table for the inline functions defined in this file. +extern const uint8_t lzma_rc_prices[RC_PRICE_TABLE_SIZE]; + + +static inline uint32_t +rc_bit_price(const probability prob, const uint32_t bit) +{ + return lzma_rc_prices[(prob ^ ((UINT32_C(0) - bit) + & (RC_BIT_MODEL_TOTAL - 1))) >> RC_MOVE_REDUCING_BITS]; +} + + +static inline uint32_t +rc_bit_0_price(const probability prob) +{ + return lzma_rc_prices[prob >> RC_MOVE_REDUCING_BITS]; +} + + +static inline uint32_t +rc_bit_1_price(const probability prob) +{ + return lzma_rc_prices[(prob ^ (RC_BIT_MODEL_TOTAL - 1)) + >> RC_MOVE_REDUCING_BITS]; +} + + +static inline uint32_t +rc_bittree_price(const probability *const probs, + const uint32_t bit_levels, uint32_t symbol) +{ + uint32_t price = 0; + symbol += UINT32_C(1) << bit_levels; + + do { + const uint32_t bit = symbol & 1; + symbol >>= 1; + price += rc_bit_price(probs[symbol], bit); + } while (symbol != 1); + + return price; +} + + +static inline uint32_t +rc_bittree_reverse_price(const probability *const probs, + uint32_t bit_levels, uint32_t symbol) +{ + uint32_t price = 0; + uint32_t model_index = 1; + + do { + const uint32_t bit = symbol & 1; + symbol >>= 1; + price += rc_bit_price(probs[model_index], bit); + model_index = (model_index << 1) + bit; + } while (--bit_levels != 0); + + return price; +} + + +static inline uint32_t +rc_direct_price(const uint32_t bits) +{ + return bits << RC_BIT_PRICE_SHIFT_BITS; +} + +#endif |