[Bug bootstrap/41241] [4.5 regression] bootstrap comparison failure

[vmakarov at redhat dot com]

------- Comment #38 from vmakarov at redhat dot com  2009-09-04 15:25 -------
Finally, I think I found what is the reason for all these bootstrap failures. 
I've changed code dealing with register preferences.  Now regnfo::reg_pref is
not null from the start and some passes (now it is regmove) using
reg_(preferred,alternative)_class returns uninitialized data instead of
GENERAL_REGS as before.

I don't see sense for these passes to use this info (it was in the old RA too:
regclass initializing reg_pref was called only in local-alloc first time)
because code in the passes assumes that reg_preferred_class returns right class
(not GENERAL_REGS).

I'll work for a work around.  I hope to send it today.  The right solution will
take more time (may be week or two).

I apologize for all that trouble I cause with my patch.  But it permitted to
find some pitfalls in RA (and the old one too).

Thanks for all your help.


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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41241