expr.c (emit_group_load, [...]): Rewrite considering the size and alignment of the structure being manipulated.

        * expr.c (emit_group_load, emit_group_store): Rewrite considering
        the size and alignment of the structure being manipulated.
        * expr.c, calls.c, function.c: Update all callers.
        * expr.h: Update prototypes.
        * cse.c (invalidate): Cope with parallels.

From-SVN: r20867