On Thu, Aug 30, 2018 at 2:12 AM Martin Sebor <mse...@gmail.com> wrote: > > The attached patch adds code to work harder to determine whether > the destination of an assignment involving MEM_REF is the same > as the destination of a prior strncpy call. The included test > case demonstrates when this situation comes up. During ccp, > dstbase and lhsbase returned by get_addr_base_and_unit_offset() > end up looking like this:
"During CCP" means exactly when? The CCP lattice tracks copies so CCP should already know that _1 == _8. I suppose during substitute_and_fold then? But that replaces uses before folding the stmt. So I'm confused. > > _8 = &pb_3(D)->a; > _9 = _8; > _1 = _9; > strncpy (MEM_REF (&pb_3(D)->a), ...); > MEM[(struct S *)_1].a[n_7] = 0; > > so the loops follow the simple assignments until we get at > the ADDR_EXPR assigned to _8 which is the same as the strncpy > destination. > > Tested on x86_64-linux. > > Martin
