[Bug middle-end/52890] Revision 185336 causes 10% degradation on cpu2000 benchmark 252.eon

[pthaugen at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52890

--- Comment #10 from Pat Haugen <pthaugen at gcc dot gnu.org> 2012-09-12 23:04:55 UTC ---
Created attachment 28181
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28181
Reduced testcase

Martin,
  Have you done any more digging on this? I just discovered that cpu2006
benchmark 471.omnetpp suffers the same problem (8 byte loads turned in to
sequence of byte loads/shifts/ors). It causes a 12% degradation on PowerPC, and
also goes away when -fno-ipa-sra is added. I'm attaching a reduced testcase
that can be compiled with g++ -S -O3 -m64 -mcpu=power7.