Re: Constant divisions not converted to multiplications

LIU Hao via Gcc <[email protected]>
Newsgroups gmane.comp.gcc.devel
Message-ID <[email protected]>
在 2026-5-21 21:49, Matteo Nicoli via Gcc 写道:
> On GCC 16.1.1 I observe the same behavior (except from the fact that it uses the AVX instruction vdivss).

The option which enables such optimization is `-freciprocal-math`: https://gcc.godbolt.org/z/YovYMMdbj

It's off by default as it may result in precision loss. It can also be enabled indirectly with 
`-funsafe-math-optimizations` or `-ffast-math`.


-- 
Best regards,
LIU Hao
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