Combine error?

[Jeffrey A Law]

  In message < 200003201600.QAA11765@cam-mail2.cambridge.arm.com >you write:
  > Nick Clifton posted a patch to do exactly that.  I objected because I 
  > thought that it was wrong for a log-link to point to a note (it happens 
  > because flow has converted the insn pointed to into a pre/post operand in 
  > another insn, but hasn't updated the link).  However, I thought Jeff had 
  > over-ruled on this one and said the patch was OK; but it doesn't seem to 
  > have got any further than that.
I didn't remember a final resolution on whether or not we should try to
kill the dead LOG_LINKS or just handle them.

I would think the only way we could get dead LOG_LINK pointers would be
due to the optimization phase of flow (auto-inc, dead code elimination
and the like) or due to combine's actions.  So it may be possible to avoid
the dead links.  I really don't know.

jeff