align skvx::Vec<N,T> to N*sizeof(T)

This increases the alignment of these vector types.  I would have liked
to keep the alignment minimal, but it's probably no big deal either way.

In terms of code generation, it doesn't make much difference for x86 or
ARMv8, but it seems hugely important for good ARMv7 NEON code.  It's a
~10x difference for the bench I've been playing around with that spends
most of its time in that SkOpts::blit_row_color32 routine.

Bug: chromium:952502
Change-Id: Ib12caad6b9b3f3f6e821ed70bfb57099db37b15f
Commit-Queue: Michael Ludwig <>
Reviewed-by: Michael Ludwig <>
Auto-Submit: Mike Klein <>
1 file changed