https://gcc.gnu.org/bugzilla/show_bug.cgi?id=123417
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> --- (In reply to Andrew Pinski from comment #5) > So it turns out we set LOOPS_MAY_HAVE_MULTIPLE_LATCHES a few places through > the compiling. BUT LOOPS_MAY_HAVE_MULTIPLE_LATCHES does not mean don't > protect the latch. It rather means the current state might have multiple > latches but it is best to protect the latches. It's always best to protect latches for the purpose of tracking loops and optimization. But actual assembler can be sometimes better when you can merge loop headers of a nest, esp. when BB re-ordering confuses things (IIRC).
