Re: Results for egcs-2.92.23 19981122 (gcc2 ss-980609 experimental) testsuite on i386-unknown-openbsd2.4

[Jeffrey A Law <law at cygnus dot com>]

  In message <vyz90gxxy76.fsf@issan.cs.uni-dortmund.de>you write:
  > Marc Espie <espie@quatramaran.ens.fr> writes:
  > 
  > |> I should add that I STILL can't give you any results for 
  > |> m68k-unknown-openbsd2.4 as I am still running into the same wall:
  > |> 
  > |> compilation of libgcc2 by xgcc for _bb ends up with an ICE
  > |> in expmed.c: 2594: Internal compiler error in function choose_multiplier
  > 
  > This is a bug in reload, it kills the REG_UNUSED notes, which cannot be
  > recomputed accurately.  As a result the second stage compiler is
  > miscompiled (more exactly the function div_and_round_double which is
  > called by choose_multiplier).  Here is a patch:
  > 
  > 
  > 1998-11-01  Andreas Schwab  <schwab@issan.cs.uni-dortmund.de>
  > 
  > 	* reload1.c (reload): Don't remove REG_UNUSED notes here, it is
  > 	impossible in general to recompute them accurately afterwards.
You still haven't resolved the  issue I raised earlier this month about this
patch.  Let's get the issue resolved so that we can install your patch.

[ ... ]
Ugh.  Conceptually I think the patch is OK.  Do we need to worry about
flow2 adding another REG_UNUSED note to an insn with an existing REG_UNUSED
note?  That could be bad (then again, maybe not).  I think we need to resolve
this issue (if we need to do anything), then install the resulting patch.

I can't think of any cases where REG_UNUSED notes were inaccurate after
reload, so I doubt keeping them is going to hurt anything.

jeff