https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64081
Bug ID: 64081 Summary: [5 Regression] r217827 prevents RTL loop unroll Product: gcc Version: 5.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: tree-optimization Assignee: unassigned at gcc dot gnu.org Reporter: izamyatin at gmail dot com Target: x86 Created attachment 34123 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=34123&action=edit reproducer Noticed that for the attached test no RTL loop unroll started to happen. It is because of changes in dom - namely, I see in dumps that dom2 complicates loop structure. (probably because of changes in lookup_avail_expr?) Looks like r217827 doesn't mean this :) Options that should be used - just "-O2 -funroll-loops"