40% performance regression SPEC2006/leslie3d on gcc-4_2-branch

[Denis Nagorny]

H. J. Lu wrote:
> We are working on complete data of SPEC CPU 2K/2006 on Core 2 Duo.
> It will take about a week. 
There are results' comparison I got for gcc 4.2 revisions 117890,
117891 and 121952 on SPEC CPU2K/2006

SPEC CPU2000:
               117891 vs 117890  121952 vs 117890
164.gzip            -0.1%            0.0%
175.vpr             -0.1%            0.8%
176.gcc             -0.1%           -0.3%
181.mcf             -0.4%           -1.3%
186.crafty          -0.8%           -0.8%
197.parser          -0.2%           -0.1%
252.eon              0.5%            0.2%
253.perlbmk         -0.8%            0.1%
254.gap             -2.5%           -0.7%
255.vortex          -0.6%           -0.2%
256.bzip2           -1.1%            0.1%
300.twolf           -0.5%            0.0%
SPECint_base2000    -0.5%           -0.2%

168.wupwise          0.0%           -0.6%
171.swim             0.8%            0.8%
172.mgrid            0.0%           -0.1%
173.applu            0.5%            2.6%
177.mesa            -0.4%            0.0%
178.galgel           0.0%           -0.1%
179.art             -0.4%            0.1%
183.equake           0.0%           -0.2%
187.facerec         -0.1%            0.1%
188.ammp             0.1%            0.1%
189.lucas            0.0%            0.0%
191.fma3d           -1.3%           -2.3%
200.sixtrack        -0.1%            0.2%
301.apsi             0.1%            0.3%
SPECfp_base2000     -0.1%            0.1%

SPEC CPU2006
               117891 vs 117890  121952 vs 117890
400.perlbench        0.0%           -0.6%
401.bzip2            0.7%            0.0%
403.gcc              0.9%            0.9%
429.mcf             -0.7%            0.0%
445.gobmk            1.4%            0.7%
456.hmmer            1.0%            1.0%
458.sjeng           -1.4%           -0.7%
462.libquantum      -1.6%            0.0%
464.h264ref         -0.5%            0.5%
471.omnetpp          0.9%            0.9%
473.astar            0.0%           -1.0%
483.xalancbmk       -0.1%            0.4%
SPECint_base2006     0.0%            0.8%

410.bwaves           0.5%            0.4%
416.gamess           0.0%           -0.8%
433.milc             0.0%            0.0%
434.zeusmp           0.0%            0.0%
435.gromacs          0.1%            0.0%
436.cactusADM       -0.1%           -0.1%
437.leslie3d       -30.1%          -30.3%
444.namd             0.0%            0.0%
447.dealII           0.0%           -1.4%
450.soplex           0.0%            0.7%
453.povray          -0.6%           -2.5%
454.calculix         0.0%           -0.4%
459.GemsFDTD       -18.6%          -18.7%
465.tonto           -1.8%           -0.9%
470.lbm              0.0%            0.0%
481.wrf             -0.6%           -0.3%
482.sphinx3          0.0%            0.0%
SPECfp_base2006     -3.5%           -3.5%

Denis