BMI2 detection in 32-bit mode #4251
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this was previously no triggered in x86 32-bit mode, due to a limitation in `bitstream.h`, that was fixed in #4248. Now, `bmi2` will be automatically detected and triggered at compilation time, if the corresponding instruction set is enabled, even in 32-bit mode. Also: updated library documentation, to feature STATIC_BMI2 build variable
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Following the fix #4248,
bmi2mode is no longer limited tox6464-bit mode.Consequently, this patch makes it possible to automatically detect and use this instruction set at compilation time, even when the target is 32-bit.
This makes it possible to use this instruction set in 32-bit mode, resulting in significant speed gains, notably on the decompression side.
Decompression speed benchmark, measured on a i7-9700k, ubuntu 24.04, gcc 13.3.0:
-m32-m32 -mavx2 -mbmi2Also: updated library documentation, to feature
STATIC_BMI2build variable