A new patch for floating point conditional mov on PPo

Jeffrey A Law law@cygnus.com
Fri Jun 19 20:31:00 GMT 1998


  In message < m0yjqpP-00026AC@ocean.lucon.org >you write:
  > I have verified that the current notice_update_cc will clear cc0 for
  > all conditional moves. Given
That wasn't the point.  What the "current" notice_update_cc does is
overly conservative.  We don't want to depend on other parts of the
compiler having overly conservative code generation -- later when someone
makes notice_update_cc less conservative they'll expose a latent bug
in your code.

It's better to make your code more robust now than depend on the overly
conservative nature of other code and have a latent, hard to find bug
show up later.  That's basic software engineering.

(I use "current" since this message was referring to the code before
a recent change from John which makes notice_update_cc less conservative).

jeff



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