Re: PATCH: [5 Regression] r219037 caused FAIL: gcc.dg/pr44194-1.c

[Jakub Jelinek <jakub@redhat.com>]

On Mon, Jan 05, 2015 at 03:16:46PM -0500, John David Anglin wrote:
> I think there may be one situation after reload that's not handled
> by the above.  frame_read is only used for const calls.  What about
> the situation where we have a non const sibcall and the frame pointer
> isn't eliminated?

After reload DSE is run after threading prologues/epilogues, end
the prologue/epilogue sequences usually contain wild reads, e.g.
(mem:BLK (scratch)) in some insn etc.
Do you have some particular testcase in mind?

That said, DSE after reload is much more limited than the DSE before reload,
so is less important, so perhaps even
  if ((HARD_FRAME_POINTER_IS_ARG_POINTER || reload_completed)
      && SIBLING_CALL_P (insn))
    {
      add_wild_read (bb_info);                                                                                                                 
      return;                                                                                                                                  
    }
might be good enough.

	Jakub