PR rtl-optimization/78355
	* doc/tm.texi.in (SLOW_UNALIGNED_ACCESS): Document that the macro only
	needs to deal with unaligned accesses.
	* doc/tm.texi: Regenerate.
	* lra-constraints.c (simplify_operand_subreg): Only invoke
	SLOW_UNALIGNED_ACCESS on innermode if the MEM is not aligned enough.

Co-Authored-By: Eric Botcazou <ebotcazou@adacore.com>

From-SVN: r242554