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	Don't initialize the first parameter of _BitScanReverse* functions
Like the document example, no need to initialize `r` to 0. https://docs.microsoft.com/en-us/cpp/intrinsics/bitscanreverse-bitscanreverse64
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		| @@ -343,8 +343,7 @@ FORCE_INLINE unsigned FSE_highbit32 (U32 val) | ||||
| { | ||||
| #   if defined(_MSC_VER)   /* Visual */ | ||||
|     unsigned long r; | ||||
|     _BitScanReverse ( &r, val ); | ||||
|     return (unsigned) r; | ||||
|     return _BitScanReverse(&r, val) ? (unsigned)r : 0; | ||||
| #   elif defined(__GNUC__) && (GCC_VERSION >= 304)   /* GCC Intrinsic */ | ||||
|     return __builtin_clz (val) ^ 31; | ||||
| #   else   /* Software version */ | ||||
|   | ||||
| @@ -353,9 +353,8 @@ MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits); | ||||
| MEM_STATIC unsigned BIT_highbit32 (U32 val) | ||||
| { | ||||
| #   if defined(_MSC_VER)   /* Visual */ | ||||
|     unsigned long r=0; | ||||
|     _BitScanReverse ( &r, val ); | ||||
|     return (unsigned) r; | ||||
|     unsigned long r; | ||||
|     return _BitScanReverse(&r, val) ? (unsigned)r : 0; | ||||
| #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */ | ||||
|     return __builtin_clz (val) ^ 31; | ||||
| #   else   /* Software version */ | ||||
|   | ||||
| @@ -356,9 +356,8 @@ MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits); | ||||
| MEM_STATIC unsigned BIT_highbit32 (U32 val) | ||||
| { | ||||
| #   if defined(_MSC_VER)   /* Visual */ | ||||
|     unsigned long r=0; | ||||
|     _BitScanReverse ( &r, val ); | ||||
|     return (unsigned) r; | ||||
|     unsigned long r; | ||||
|     return _BitScanReverse(&r, val) ? (unsigned)r : 0; | ||||
| #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */ | ||||
|     return __builtin_clz (val) ^ 31; | ||||
| #   else   /* Software version */ | ||||
|   | ||||
| @@ -627,9 +627,8 @@ MEM_STATIC size_t BIT_readBitsFast(BIT_DStream_t* bitD, unsigned nbBits); | ||||
| MEM_STATIC unsigned BIT_highbit32 (U32 val) | ||||
| { | ||||
| #   if defined(_MSC_VER)   /* Visual */ | ||||
|     unsigned long r=0; | ||||
|     _BitScanReverse ( &r, val ); | ||||
|     return (unsigned) r; | ||||
|     unsigned long r; | ||||
|     return _BitScanReverse(&r, val) ? (unsigned)r : 0; | ||||
| #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */ | ||||
|     return __builtin_clz (val) ^ 31; | ||||
| #   else   /* Software version */ | ||||
|   | ||||
| @@ -756,9 +756,8 @@ MEM_STATIC size_t BITv05_readBitsFast(BITv05_DStream_t* bitD, unsigned nbBits); | ||||
| MEM_STATIC unsigned BITv05_highbit32 (U32 val) | ||||
| { | ||||
| #   if defined(_MSC_VER)   /* Visual */ | ||||
|     unsigned long r=0; | ||||
|     _BitScanReverse ( &r, val ); | ||||
|     return (unsigned) r; | ||||
|     unsigned long r; | ||||
|     return _BitScanReverse(&r, val) ? (unsigned)r : 0; | ||||
| #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */ | ||||
|     return __builtin_clz (val) ^ 31; | ||||
| #   else   /* Software version */ | ||||
|   | ||||
| @@ -860,9 +860,8 @@ MEM_STATIC size_t BITv06_readBitsFast(BITv06_DStream_t* bitD, unsigned nbBits); | ||||
| MEM_STATIC unsigned BITv06_highbit32 ( U32 val) | ||||
| { | ||||
| #   if defined(_MSC_VER)   /* Visual */ | ||||
|     unsigned long r=0; | ||||
|     _BitScanReverse ( &r, val ); | ||||
|     return (unsigned) r; | ||||
|     unsigned long r; | ||||
|     return _BitScanReverse(&r, val) ? (unsigned)r : 0; | ||||
| #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */ | ||||
|     return __builtin_clz (val) ^ 31; | ||||
| #   else   /* Software version */ | ||||
|   | ||||
| @@ -530,9 +530,8 @@ MEM_STATIC size_t BITv07_readBitsFast(BITv07_DStream_t* bitD, unsigned nbBits); | ||||
| MEM_STATIC unsigned BITv07_highbit32 (U32 val) | ||||
| { | ||||
| #   if defined(_MSC_VER)   /* Visual */ | ||||
|     unsigned long r=0; | ||||
|     _BitScanReverse ( &r, val ); | ||||
|     return (unsigned) r; | ||||
|     unsigned long r; | ||||
|     return _BitScanReverse(&r, val) ? (unsigned)r : 0; | ||||
| #   elif defined(__GNUC__) && (__GNUC__ >= 3)   /* Use GCC Intrinsic */ | ||||
|     return __builtin_clz (val) ^ 31; | ||||
| #   else   /* Software version */ | ||||
|   | ||||
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