The testcase from PR 16975 shows the tree-ssa aliasing pass can be slow. You can get the testcase from: <http://www.math.purdue.edu/~lucier/GNATS/GNATS-12/_num.i.gz> Here is the results from my build (yes with --disable-checking): tree PTA : 35.74 (38%) usr 0.12 ( 1%) sys 37.63 (33%) wall
Note this testcase has a large number of computed gotos. -- Summary: [4.0 Regression] tree-ssa aliasing slow Product: gcc Version: 4.0.0 Status: UNCONFIRMED Keywords: compile-time-hog Severity: normal Priority: P2 Component: tree-optimization AssignedTo: dnovillo at gcc dot gnu dot org ReportedBy: pinskia at gcc dot gnu dot org CC: gcc-bugs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18419