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author | Ferenc Arn <tagcup@yahoo.com> | 2017-10-26 16:41:47 -0400 |
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committer | Ferenc Arn <tagcup@yahoo.com> | 2017-10-26 16:41:47 -0400 |
commit | 01815e9b5f1ec97d0018ee843a07fa73f450f1bf (patch) | |
tree | e810d42b26e885a6374a657f1b1092521dfc0a94 /thirdparty/zstd/common/bitstream.h | |
parent | 2987e6ce4ffc69da5efc0903cc00ce12e72d2125 (diff) | |
download | redot-engine-01815e9b5f1ec97d0018ee843a07fa73f450f1bf.tar.gz |
Update zstd to 1.3.2.
Diffstat (limited to 'thirdparty/zstd/common/bitstream.h')
-rw-r--r-- | thirdparty/zstd/common/bitstream.h | 58 |
1 files changed, 35 insertions, 23 deletions
diff --git a/thirdparty/zstd/common/bitstream.h b/thirdparty/zstd/common/bitstream.h index 06121f21c5..2094823fe2 100644 --- a/thirdparty/zstd/common/bitstream.h +++ b/thirdparty/zstd/common/bitstream.h @@ -169,33 +169,39 @@ MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits); ****************************************************************/ MEM_STATIC unsigned BIT_highbit32 (register U32 val) { + assert(val != 0); + { # if defined(_MSC_VER) /* Visual */ - unsigned long r=0; - _BitScanReverse ( &r, val ); - return (unsigned) r; + unsigned long r=0; + _BitScanReverse ( &r, val ); + return (unsigned) r; # elif defined(__GNUC__) && (__GNUC__ >= 3) /* Use GCC Intrinsic */ - return 31 - __builtin_clz (val); + return 31 - __builtin_clz (val); # else /* Software version */ - static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, - 11, 14, 16, 18, 22, 25, 3, 30, - 8, 12, 20, 28, 15, 17, 24, 7, - 19, 27, 23, 6, 26, 5, 4, 31 }; - U32 v = val; - v |= v >> 1; - v |= v >> 2; - v |= v >> 4; - v |= v >> 8; - v |= v >> 16; - return DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27]; + static const unsigned DeBruijnClz[32] = { 0, 9, 1, 10, 13, 21, 2, 29, + 11, 14, 16, 18, 22, 25, 3, 30, + 8, 12, 20, 28, 15, 17, 24, 7, + 19, 27, 23, 6, 26, 5, 4, 31 }; + U32 v = val; + v |= v >> 1; + v |= v >> 2; + v |= v >> 4; + v |= v >> 8; + v |= v >> 16; + return DeBruijnClz[ (U32) (v * 0x07C4ACDDU) >> 27]; # endif + } } /*===== Local Constants =====*/ -static const unsigned BIT_mask[] = { 0, 1, 3, 7, 0xF, 0x1F, 0x3F, 0x7F, - 0xFF, 0x1FF, 0x3FF, 0x7FF, 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, - 0xFFFF, 0x1FFFF, 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF, - 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF }; /* up to 26 bits */ - +static const unsigned BIT_mask[] = { + 0, 1, 3, 7, 0xF, 0x1F, + 0x3F, 0x7F, 0xFF, 0x1FF, 0x3FF, 0x7FF, + 0xFFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF, 0x1FFFF, + 0x3FFFF, 0x7FFFF, 0xFFFFF, 0x1FFFFF, 0x3FFFFF, 0x7FFFFF, + 0xFFFFFF, 0x1FFFFFF, 0x3FFFFFF, 0x7FFFFFF, 0xFFFFFFF, 0x1FFFFFFF, + 0x3FFFFFFF, 0x7FFFFFFF}; /* up to 31 bits */ +#define BIT_MASK_SIZE (sizeof(BIT_mask) / sizeof(BIT_mask[0])) /*-************************************************************** * bitStream encoding @@ -217,11 +223,14 @@ MEM_STATIC size_t BIT_initCStream(BIT_CStream_t* bitC, } /*! BIT_addBits() : - * can add up to 26 bits into `bitC`. + * can add up to 31 bits into `bitC`. * Note : does not check for register overflow ! */ MEM_STATIC void BIT_addBits(BIT_CStream_t* bitC, size_t value, unsigned nbBits) { + MEM_STATIC_ASSERT(BIT_MASK_SIZE == 32); + assert(nbBits < BIT_MASK_SIZE); + assert(nbBits + bitC->bitPos < sizeof(bitC->bitContainer) * 8); bitC->bitContainer |= (value & BIT_mask[nbBits]) << bitC->bitPos; bitC->bitPos += nbBits; } @@ -232,6 +241,7 @@ MEM_STATIC void BIT_addBitsFast(BIT_CStream_t* bitC, size_t value, unsigned nbBits) { assert((value>>nbBits) == 0); + assert(nbBits + bitC->bitPos < sizeof(bitC->bitContainer) * 8); bitC->bitContainer |= value << bitC->bitPos; bitC->bitPos += nbBits; } @@ -242,7 +252,7 @@ MEM_STATIC void BIT_addBitsFast(BIT_CStream_t* bitC, MEM_STATIC void BIT_flushBitsFast(BIT_CStream_t* bitC) { size_t const nbBytes = bitC->bitPos >> 3; - assert( bitC->bitPos <= (sizeof(bitC->bitContainer)*8) ); + assert(bitC->bitPos < sizeof(bitC->bitContainer) * 8); MEM_writeLEST(bitC->ptr, bitC->bitContainer); bitC->ptr += nbBytes; assert(bitC->ptr <= bitC->endPtr); @@ -258,7 +268,7 @@ MEM_STATIC void BIT_flushBitsFast(BIT_CStream_t* bitC) MEM_STATIC void BIT_flushBits(BIT_CStream_t* bitC) { size_t const nbBytes = bitC->bitPos >> 3; - assert( bitC->bitPos <= (sizeof(bitC->bitContainer)*8) ); + assert(bitC->bitPos < sizeof(bitC->bitContainer) * 8); MEM_writeLEST(bitC->ptr, bitC->bitContainer); bitC->ptr += nbBytes; if (bitC->ptr > bitC->endPtr) bitC->ptr = bitC->endPtr; @@ -350,12 +360,14 @@ MEM_STATIC size_t BIT_getMiddleBits(size_t bitContainer, U32 const start, U32 co # endif return _bextr_u32(bitContainer, start, nbBits); #else + assert(nbBits < BIT_MASK_SIZE); return (bitContainer >> start) & BIT_mask[nbBits]; #endif } MEM_STATIC size_t BIT_getLowerBits(size_t bitContainer, U32 const nbBits) { + assert(nbBits < BIT_MASK_SIZE); return bitContainer & BIT_mask[nbBits]; } |