------- Comment #60 from bonzini at gnu dot org  2009-05-06 10:47 -------
Actually those are created by -fmove-loop-invariants.  With -O1
-fforward-propagate -fno-move-loop-invariants I get:

                   4.5 -O1 -ffw-prop -fno-move-loop-inv
LOOP 1                183
INNER LOOP 1.1        116
LOOP 2                25

You should be able to get performance close to 4.2 or better with options "-O1
-fforward-propagate -fno-move-loop-invariants -fschedule-insns2".  If you do,
this means two things:

1) That the bug is in the register pressure estimations of
-fno-move-loop-invariants, and merely exposed by the fwprop patch.

2) That maybe you should start from -O2 and go backwards, eliminating
optimizations that do not help you or cause high compilation time, instead of
using -O1.


-- 

bonzini at gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |WAITING


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33928

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