On Wed, Aug 03, 2005 at 03:50:09PM +0100, Nathan Sidwell wrote: > Gunther Nikl wrote: > >I am trying to add instructions into function prologue/epilogue. These > >instructions shall save and load "fixed" registers to avoid assembly. > > > >Register saving in the prologue appears to work. The restore code in the > >epilogue aborts in flow.c/propagate_one_insn with > > > > "Attempt to delete prologue/epilogue insn" > > > >unless the stackslot was marked with MEM_VOLATILE_P. I don't think thats > >the proper fix. > > you can add a (USE reg) after the restore in the prologue. Then flow > considers the register, and the preceding load, to be live at that point.
Thank you. With "emit_insn (gen_rtx_USE (VOIDmode, reg))" the abort disappears. The same approach seems to fix the loads in the prologue. I hope that this is the correct solution. On Wed, Aug 03, 2005 at 03:53:21PM +0100, Nathan Sidwell wrote: > Nathan Sidwell wrote: > > >you can add a (USE reg) after the restore in the prologue. Then flow > in the EPILOGUE, of course I wouldn't have notice this mistake without your mail. Thank you for the help. Gunther > >considers the register, and the preceding load, to be live at that point.
