diff options
Diffstat (limited to 'media/libwebp/utils/utils.h')
-rw-r--r-- | media/libwebp/utils/utils.h | 34 |
1 files changed, 28 insertions, 6 deletions
diff --git a/media/libwebp/utils/utils.h b/media/libwebp/utils/utils.h index d22151b0fc..20abf03c69 100644 --- a/media/libwebp/utils/utils.h +++ b/media/libwebp/utils/utils.h @@ -42,6 +42,10 @@ extern "C" { #endif #endif // WEBP_MAX_ALLOCABLE_MEMORY +static WEBP_INLINE int CheckSizeOverflow(uint64_t size) { + return size == (size_t)size; +} + // size-checking safe malloc/calloc: verify that the requested size is not too // large, or return NULL. You don't need to call these for constructs like // malloc(sizeof(foo)), but only if there's picture-dependent size involved @@ -92,14 +96,14 @@ static WEBP_INLINE uint32_t GetLE32(const uint8_t* const data) { // Store 16, 24 or 32 bits in little-endian order. static WEBP_INLINE void PutLE16(uint8_t* const data, int val) { assert(val < (1 << 16)); - data[0] = (val >> 0); - data[1] = (val >> 8); + data[0] = (val >> 0) & 0xff; + data[1] = (val >> 8) & 0xff; } static WEBP_INLINE void PutLE24(uint8_t* const data, int val) { assert(val < (1 << 24)); PutLE16(data, val & 0xffff); - data[2] = (val >> 16); + data[2] = (val >> 16) & 0xff; } static WEBP_INLINE void PutLE32(uint8_t* const data, uint32_t val) { @@ -107,24 +111,33 @@ static WEBP_INLINE void PutLE32(uint8_t* const data, uint32_t val) { PutLE16(data + 2, (int)(val >> 16)); } -// Returns (int)floor(log2(n)). n must be > 0. // use GNU builtins where available. #if defined(__GNUC__) && \ ((__GNUC__ == 3 && __GNUC_MINOR__ >= 4) || __GNUC__ >= 4) +// Returns (int)floor(log2(n)). n must be > 0. static WEBP_INLINE int BitsLog2Floor(uint32_t n) { return 31 ^ __builtin_clz(n); } +// counts the number of trailing zero +static WEBP_INLINE int BitsCtz(uint32_t n) { return __builtin_ctz(n); } #elif defined(_MSC_VER) && _MSC_VER > 1310 && \ (defined(_M_X64) || defined(_M_IX86)) #include <intrin.h> #pragma intrinsic(_BitScanReverse) +#pragma intrinsic(_BitScanForward) static WEBP_INLINE int BitsLog2Floor(uint32_t n) { - unsigned long first_set_bit; + unsigned long first_set_bit; // NOLINT (runtime/int) _BitScanReverse(&first_set_bit, n); return first_set_bit; } -#else // default: use the C-version. +static WEBP_INLINE int BitsCtz(uint32_t n) { + unsigned long first_set_bit; // NOLINT (runtime/int) + _BitScanForward(&first_set_bit, n); + return first_set_bit; +} +#else // default: use the (slow) C-version. +#define WEBP_HAVE_SLOW_CLZ_CTZ // signal that the Clz/Ctz function are slow // Returns 31 ^ clz(n) = log2(n). This is the default C-implementation, either // based on table or not. Can be used as fallback if clz() is not available. #define WEBP_NEED_LOG_TABLE_8BIT @@ -139,6 +152,15 @@ static WEBP_INLINE int WebPLog2FloorC(uint32_t n) { } static WEBP_INLINE int BitsLog2Floor(uint32_t n) { return WebPLog2FloorC(n); } + +static WEBP_INLINE int BitsCtz(uint32_t n) { + int i; + for (i = 0; i < 32; ++i, n >>= 1) { + if (n & 1) return i; + } + return 32; +} + #endif //------------------------------------------------------------------------------ |