Re: PING: PATCH [9/n]: Prepare x32: PR middle-end/47383: ivopts miscompiles Pmode != ptr_mode

["Ulrich Weigand" <uweigand at de dot ibm dot com>]

H.J. Lu wrote:

> > However, this still seems odd to me, as I had understood the address in
> > a TARGET_MEM_REF needs to be an *address*, i.e. use address_mode. =A0If
> > this is not true (has changed?) a lot of other places would need to
> > change as well ...
> 
> I was told that TARGET_MEM_REF needs ptr_mode.

Can you elaborate?  We are talking about the mode returned from
addr_for_mem_ref here.  I do now understand how this can be anything
but an address mode:

If you look at the users of addr_for_mem_ref, they all look someting
like this:

          op0 = addr_for_mem_ref (&addr, as, true);
          op0 = memory_address_addr_space (mode, op0, as);
          mem = gen_rtx_MEM (mode, op0);

So the result is used as address argument to create a MEM.  This must
certainly be address mode (Pmode) then -- that's basically the definition
of address mode (the mode of the address argument to MEM).

Bye,
Ulrich

-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com