https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61320
--- Comment #14 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to Richard Biener from comment #12) > (In reply to Eric Botcazou from comment #11) > > > So I am testing the patch right now and should be able to send it > > > tomorrow. > > > However, the code already shall already mark the load with the actual > > > alignment the access is being done with. Therefore it seems to me that > > > something in the backend fails to split the unaligned load into several > > > aligned load. > > > > But what would be the point of this round trip exactly? > > I'd say > > Index: tree-ssa-math-opts.c > =================================================================== > --- tree-ssa-math-opts.c (revision 211170) > +++ tree-ssa-math-opts.c (working copy) > @@ -2149,7 +2149,8 @@ bswap_replace (gimple stmt, gimple_stmt_ > unsigned align; > > align = get_object_alignment (src); > - if (bswap && SLOW_UNALIGNED_ACCESS (TYPE_MODE (load_type), align)) > + if (align < GET_MODE_ALIGNMENT (TYPE_MODE (load_type)) > + && SLOW_UNALIGNED_ACCESS (TYPE_MODE (load_type), align)) > return false; > > /* Compute address to load from and cast according to the size > > is obvious (and pre-approved). obvious as a workaround, that is.
