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[RFB] IRA and regclass both ignore '!' attribute


I noticed while looking into a register allocation issue in 4.1.1,
that regclass was ignoring '!' attribute so it would sometimes give
the wrong result so we get performance issue (selecting GPR instead of
FPR).  So I saw that IRA also ignore it too which seems wrong and
seems like the code was copied from regclass.  preprocess_constraints
and find_reloads both take '!' into account.

Can someone benchmark this on x86 and PPC? I can only really benchmark
with a 4.3 or 4.1.1 based compiler with a subset of SPEC.  The 4.1.1
based compiler gets a nice but small 0.6% performance increase and a
small code decrease.

Thanks,
Andrew Pinski

ChangeLog:
* regclass.c (record_reg_classes): Take into account '!'.
(record_reg_classes): Likewise.

Attachment: t.diff.txt
Description: Text document


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