[flac-dev] about word size in bitreader/bitwriter

[lvqcl]

Miroslav Lichvar wrote:

> In the measurements comparing 32-bit and 64-bit words you posted
> later, I'm wondering why there is a slow down in decoding of 24-bit
> files. Does profiling show it comes from the read_rice_signed_block()
> function or something else? Could it be slower SWAP_BE_WORD_TO_HOST or
> COUNT_ZERO_MSBS2?

The difference is so small that it's difficult to find a place
where FLAC__BYTES_PER_WORD==8 is slower than 4.
Also I don't know how to perform profiling in MSYS/MinGW ecosystem.

Profiling in MSVS2015 hints that for some reason crc16_update_word_()
may take more time if FLAC__BYTES_PER_WORD==8. Maybe the new code
(the patch is attached) is faster?
Currently I can't measure the difference with high enough precision,
the measurement error on my current system is too high :(
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