Hi,
Given tree node (thus struct dependence_info) is kept and shadow copied on RTL,
it is unsafe to pass non-dependent info to RTL in case of loop unrolling etc.
This patch adds an interface clearing all dependence_info with fixed access
length tag before entering RTL world.  We could do it just before expanding,
but for now it is done in loopdone given predcom is the only motivation pass
that I know.
Bootstrap and test in series.  Is it OK?

Thanks,
bin
2017-08-10  Bin Cheng  <bin.cheng@arm.com>

	* tree-ssa-address.c (clear_dependence_info): New function.
	(clear_all_dependence_info): New function.
	* tree-ssa-address.h (clear_all_dependence_info): New declaration.
	* tree-ssa-loop.c: Include tree-ssa-address.h.
	(tree_ssa_loop_done): Call clear_all_dependence_info.