ffmpeg | branch: master | Martin Storsjö <mar...@martin.st> | Tue Sep 24 11:44:19 2024 +0300| [b4d9fa6cb93a3ef8209508b2fb9cd1dc95f03090] | committer: Martin Storsjö
compat: Fix the fallback definition of stdc_trailing_zeros While shifting "value" to left, we would iterate through all bits of an unsigned long long, while we only expect to count through "size * CHAR_BIT" bits; instead shift bits to the right and just count the trailing zeros. This fixes fate with MSVC. Signed-off-by: Martin Storsjö <mar...@martin.st> > http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=b4d9fa6cb93a3ef8209508b2fb9cd1dc95f03090 --- compat/stdbit/stdbit.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/compat/stdbit/stdbit.h b/compat/stdbit/stdbit.h index b434fc2357..53419cf9f9 100644 --- a/compat/stdbit/stdbit.h +++ b/compat/stdbit/stdbit.h @@ -178,11 +178,14 @@ static inline unsigned int stdc_trailing_zeros_uc(unsigned char value) static inline unsigned int __stdc_trailing_zeros(unsigned long long value, unsigned int size) { - unsigned int zeros = size * CHAR_BIT; + unsigned int zeros = 0; - while (value != 0) { - value <<= 1; - zeros--; + if (!value) + return size * CHAR_BIT; + + while ((value & 1) == 0) { + value >>= 1; + zeros++; } return zeros; _______________________________________________ ffmpeg-cvslog mailing list ffmpeg-cvslog@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-cvslog To unsubscribe, visit link above, or email ffmpeg-cvslog-requ...@ffmpeg.org with subject "unsubscribe".
