[Bug target/54716] Select best typed instruction for bitwise operations

jakub at gcc dot gnu.org gcc-bugzilla@gcc.gnu.org
Wed Sep 26 13:46:00 GMT 2012


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54716

--- Comment #1 from Jakub Jelinek <jakub at gcc dot gnu.org> 2012-09-26 13:46:25 UTC ---
Created attachment 28282
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28282
gcc48-pr54716.patch

Untested patch to optimize this.

Unfortunately it will also change generated code for:
__m256d
i (__m256d x, __m256d y)
{
  return (__m256d) _mm256_or_si256 ((__m256i) x, (__m256i) y);
}

Not sure if that is an issue or not.  If we wanted to emit what the user for
whatever reason asked for, the builtin expander could perhaps in those cases
copy one of the arguments into a temporary pseudo before expansion.



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