[Bug rtl-optimization/37273] [4.4/4.5/4.6 Regression] IRA does not re-materializes addresses (loads from the TOC)

[law at redhat dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37273

--- Comment #7 from Jeffrey A. Law <law at redhat dot com> 2011-01-21 17:13:35 UTC ---
SPEC 2k6 testing on x86-64 is a wash for integer codes.  Small improvement for
403.gcc 462.libquantum and small regressions for 456.hmmr and 471.omnetpp are
evident.  There's a couple other tests which seem to have a tiny bias for
improvement, but without many more runs it'd be impossible to know if the
improvements are in the noise or not.  The net specint change is a 14.5 ->
14.6, but I wouldn't put a lot of stock into that.

FP shows a big improvement for 454.calculix and a small improvement for
459.gemsfdtd.  Small regressions are seen for 410.bwaves, 433.milc and
434.zeusmp, and 437.leslie3d.  The improvement for calculix dwarfs the minor
regressions and is probably responsible for the 13.6->13.7 improvement in the
FP base.

I've also verified that the patch consistently improves code density on x86 and
gives us the desired code on PPC for the testcase in the PR.

And, at least in my mind, the patch makes sense and I'll be posting it shortly.