[PING] [PATCH] faster string operations for bulldozer (take 2)

[Ondřej Bílka]

On Fri, Apr 26, 2013 at 12:23:21PM -0700, Roland McGrath wrote:
> > > +      /* Assume unaligned loads are fast when avx is available.  */
> 
> AVX in caps.
> 
> > > +      if ((ecx & bit_AVX) != 0)
> > > +	__cpu_features.feature[index_Fast_Rep_String]
> > > +	  |= ( bit_Fast_Unaligned_Load);
> 
> Drop the excess parens (and the excess space).
> 
> I didn't follow whatever previous discussion there was about the substance
> of this.  What is the rationale/evidence that AVX is (and always will be)
> correlated with efficiency of unaligned loads?

On bulldozer unaligned loads have small penalty. You could read about
buldozer improvements or test it by simple benchmark.

And what evidence that avx on intel processors is always
correlated with efficiency of unaligned loads?