http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57786
Bug ID: 57786
Summary: Waste work in distribute_notes()
Product: gcc
Version: 4.9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: pchang9 at cs dot wisc.edu
CC: nistor1 at illinois dot edu
Created attachment 30424
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=30424&action=edit
Suggested patch
The problem appears in revision 200588 in version 4.9. I have attached a
one-line patch that fixes it.
In method "distribute_notes()" in combine.c, the loop on line 13584 should
break immediately after "all_used" is set to 0. All the iterations after
"all_used" set to 0 do not perform any useful work, at best they just set
"all_used" again to 0.
