[Bug target/59163] [4.8/4.9 Regression] program compiled with g++ -O3 segfaults

[ubizjak at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59163

--- Comment #18 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to Jakub Jelinek from comment #17)
> Perhaps add new attribute ssememalign, with default 0, which would be
> (maximum for all alternatives) required alignment for memory operands in the
> instruction pre-AVX, or 0 for GET_MODE_ALIGNMENT.  So, instructions that can
> handle completely unaligned loads/stores in all alternatives would have
> ssememalign 8,
> instructions that require everything properly aligned would have default
> ssememalign 0, and say movlps/movhps would have ssememalign 64.  The default
> would be conservatively correct, so whether instructions would have
> ssememalign attribute would be just an optimization issue (but, if it would
> be non-zero, it would have to be correct).

This sounds like a good approach to me.