On Dec 7, 2007 5:01 PM, Chris Lattner <[EMAIL PROTECTED]> wrote: > >> + // Visit all of the instructions of the loop. We want to visit > >> the subloops > >> + // first, though, so that we can hoist their invariants first > >> into their > >> + // containing loop before we process that loop. > >> + SmallVector<MachineLoop*, 16> Loops; > >> + GatherAllLoops(L, Loops); > > > > Seems to me this can be smarter. When you are gathering the loops, put > > loops of greater depth in the front of the queue then HoistRegion > > won't have to check if the BB is in the current loop level? > > This should do a simple postorder traversal of the loop nest, there > is no need to make a vector of the loops. This ensures you visit > inner loops before outer loops etc. > Doh! Yeah, it's easier to just do it without the vector.
> >> + // Now move the instructions to the predecessors. > >> + for (std::vector<MachineBasicBlock*>::iterator > >> + I = Preds.begin(), E = Preds.end(); I != E; ++I) > >> + MoveInstToBlock(*I, MI.clone()); > > > > This will create multiple copies, it seems bad. Again, this should be > > fixable with a loop preheader? > > Furthermore, this won't work, you'd have to insert phi nodes etc. > You really really really don't want to do this bill. Only handle > loops that have a header with one predecessor that is outside the > loop plz, > Ah! Good point. When there's pre-headers, I'll be able to handle this much nicer. In the meantime, I'll make sure that there's only one predecessor. -bw _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
