[Bug target/49263] SH Target: underutilized "TST #imm, R0" instruction

[kkojima at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49263

--- Comment #4 from Kazumoto Kojima <kkojima at gcc dot gnu.org> 2011-06-22 22:34:04 UTC ---
Yes, that peephole doesn't catch all the patterns which could
make tst #imm8,r0 use.  Perhaps it would be a good idea to get
numbers for the test like CSiBE test with the vanilla and new
insns/peepholes patched compilers.  Something covers 80% of
the possible cases in the usual working set, it would be enough
successful for such a micro-optimization, I guess.

Cost patch looks fine to me.  Could you propose it as a separate
patch on gcc-patches list with an appropriate ChangeLog entry?
When proposing it, please refer how you've tested it.  Also
the numbers got with the patch are highly welcome.

BTW, do you have FSF copyright assignment for your GCC work?
Although the cost patch itself is essentially several lines which
doesn't require copyright assignment, the other changes you've
proposed clearly require the paper work, I think.