[RFA] Backport strcmp fixes to 3.3 branch

[Ulrich Weigand]

Hello,

a year ago, Jakub fixed a bug causing crashes in strcmp 
on s390 due to accesses beyond the end of the string,
by introducing new cmpmem* named patterns.

While this is in mainline since 3.4 and has been backported
to the vendor 3.3-based branches as well, for some reason
it never made it into the 3.3 branch proper, even though
as far as I recall it was supposed to.

Now, we've received a real-world bug report due to this
problem from a customer using a 3.3 compiler, and I'm 
wondering whether it would be a good idea to actually
backport the fix now for 3.3.5.

I've gone back to Jakub's patch:
http://gcc.gnu.org/ml/gcc-patches/2003-07/msg01153.html
and it does in fact still apply cleanly to the current
3.3 branch.  I've also completed bootstrap/regtest on
s390-ibm-linux and s390x-ibm-linux; the customer verified
that his problem is fixed by the patch as well.

Is this patch OK for 3.3?

Bye,
Ulrich


-- 
  Dr. Ulrich Weigand
  weigand@informatik.uni-erlangen.de