Re: new x86 cmpmemsi expander, and adjustments for cmpstrn*

2019-09-25 Thread Alexandre Oliva
On Sep 10, 2019, Alexandre Oliva wrote: > This patchset fixes some latent problems in cmpstrn* patterns for x86, > and introduces cmpmemsi for short fixed-size memcmp. Ping? https://gcc.gnu.org/ml/gcc-patches/2019-09/msg00701.html > Would it make sense to install the test program somewhere?

new x86 cmpmemsi expander, and adjustments for cmpstrn*

2019-09-10 Thread Alexandre Oliva
This patchset fixes some latent problems in cmpstrn* patterns for x86, and introduces cmpmemsi for short fixed-size memcmp. I've verified that repz cmpsb is not a good choice for memcmp, performance-wise, so I turned to movbe/bswapped loads and unsigned compares. Those have performed better than