From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Law To: TorbjXrn Lindh Cc: gcc@gcc.gnu.org Subject: Re: H8300H Tiny Date: Mon, 12 Aug 2002 15:12:00 -0000 Message-id: <200208122215.g7CMFlE06213@porcupine.slc.redhat.com> References: X-SW-Source: 2002-08/msg00697.html In message < Pine.LNX.3.91.1020810210836.7852B-100000@samuraj.c3l.tyreso.se >, To rbjXrn Lindh writes: >Hitachi have generated a number of so called Tiny H8:s, for instance the >H8/3664F. These have an h8300h cpu but are limited to a 64k address >space. > >The problem with gcc-3.1 (and as far as I can see, the current cvs version >too) is that if I use h8300 mode, I don't take advantage of the added >instructions, adressing modes etc of the h8300h cpu. But if I use the >h8300h mode the addressing gets far to long: For the H8/300H and H8/S GCC only supports "Advanced Mode". What you want is referred to as "Normal Mode" in the H8 documentation. At this time "Normal Mode" is not supported on the H8/300H or H8/S chips. There is no technical reason why "Normal Mode" couldn't be added -- however, I'm not aware of anyone working to add support for "Normal Mode" to the H8 port. >I have looked at the code, and one possible way seems to be to define a >new target that differs slightly from the h8300h target. You'd want to modify the existing H8 target. You'd want to have smaller pointers, then you'd have to audit all code which is conditional on the H8/300H or H8/S and determine which are still appropriate in normal mode. jeff