[Bug middle-end/44297] New: Big spec cpu2006 prefetch regressions on gcc 4.6 on x86

[changpeng dot fang at amd dot com]

Tests are on amd-linux64 system with -O3 -fprefetch-loop-arrays

Compare gcc-4.6-20100522.tar.bz2 to gcc-4.6-20100515.tar.bz2
459.GemsFDTD: -32.6%
434.zeusmp:   -13.6%

If I replace tree-ssa-loop-prefetch.c in gcc-4.6-20100522.tar.bz2 with the one
in gcc-4.6-20100515.tar.bz2, The regression disappears.


-- 
           Summary: Big spec cpu2006 prefetch regressions on gcc 4.6 on x86
           Product: gcc
           Version: tree-ssa
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: changpeng dot fang at amd dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44297