Running the attached testcase with trunk r131577 on SPU with -dm -fmodulo-sched -O2 flags (which enables also do-loop optimization) demonstartes the fact that the branch probability is not reserved with do-loop optimization. This causes a major preformance regression (of about 40%) when tested with some similar benchmark as there is no hardware branch prediction on SPU.
-- Summary: branch probability is not reserved with do-loop optimization Product: gcc Version: 4.3.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: rtl-optimization AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: eres at il dot ibm dot com http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34826