This is split off from PR38474 for clarity, see steven's comment #35 in that PR.
Compiling the testcase of that PR (http://gcc.gnu.org/bugzilla/attachment.cgi?id=16873) should be illuminating -- Summary: quadratic behaviour in find_temp_slot_from_address. Product: gcc Version: 4.4.0 Status: UNCONFIRMED Keywords: compile-time-hog Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: jv244 at cam dot ac dot uk OtherBugsDependingO 38474 nThis: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38586