[PATCH] Builtin strcpy/strncpy/memcpy/strcmp/fputs fixes and optimizations

[Kaveh R. Ghazi]

 > From: Richard Henderson <rth@redhat.com>
 > 
 > On Wed, Nov 29, 2000 at 06:29:31PM -0500, Michael Meissner wrote:
 > > Assuming you change:
 > > 	strcmp ("constant-string", pointer)
 > > into
 > > 	memcmp ("constant-string", pointer, sizeof ("constant-string")-1),
 > > what happens if memcmp on the machine is aggresive and reads multiple
 > > words at a time to hide the memory latency.
 > 
 > Well, we don't do this transformation in general, only when
 > we can inline the memcmp.  There are currently only three
 > targets that implement cmpstrsi, and none of them do this
 > multiple read optimization.
 > 
 > So perhaps we just need to add commentary somewhere...
 > r~

Heh, agreed:
http://gcc.gnu.org/ml/gcc-patches/2000-03/msg00789.html

Would you then please reconsider this patch?  (It probably needs
updating, but the general concept of strncmp -> expand_builtin_memcmp
is what I'd like approval for.)
http://gcc.gnu.org/ml/gcc-patches/2000-03/msg00746.html

The current builtin strncmp becomes expand_builtin_strcmp if one of
the strings strlen < 'n' ('n' is the length parameter.)  That in turn
calls expand_builtin_memcmp.  I'd like to have strncmp call
expand_builtin_memcmp directly and use a len parameter clamped at one
of the strings strlen or 'n', which ever is lower.

		Thanks,
		--Kaveh
--
Kaveh R. Ghazi			Engagement Manager / Project Services
ghazi@caip.rutgers.edu		Qwest Internet Solutions