On Mon, Aug 19, 2019 at 10:07:11AM -0500, Segher Boessenkool wrote: > ? As I remember there were a few other ideas from Richard Biener and > Segher Boessenkool.? I also proposed to add a new address register which > will be always a fixed stack memory slot at the end. Unfortunately I am > not familiar with the target and the port to say in details how to do > it.? But I think it is worth to try. The m68hc11 port used the fake Z register approach, and I believe it had some special machine pass to get rid of it right before assembler output. (r171302 is when it was removed -- last version was https://gcc.gnu.org/git/?p=gcc.git;a=blob;f=gcc/config/m68hc11/m68hc11.c;h=1e414102c3f1fed985e4fb8db7954342e965190b;hb=bae8bb65d842d7ffefe990c1f0ac004491f3c105#l4061 for the machine reorg stuff). No idea how well it works... But it's only needed if you are forced to have a frame pointer IIUC? Segher
Most of these suggestions involve adding some sort of virtual registers So I hacked the machine description to add two new registers Z1 and Z2 with the same mode as X and Y. Obviously the assembler balks at this. However the compiler still ICEs at the same place as before. So this suggests that our original diagnosis, viz: there are not enough address registers was not accurate, and in fact there is some other problem? J' -- Avoid eavesdropping. Send strong encrypted email. PGP Public key ID: 1024D/2DE827B3 fingerprint = 8797 A26D 0854 2EAB 0285 A290 8A67 719C 2DE8 27B3 See http://sks-keyservers.net or any PGP keyserver for public key.