On Dec 12, 2007 11:32 AM, Evan Cheng <[EMAIL PROTECTED]> wrote: > On Dec 12, 2007, at 11:12 AM, Bill Wendling wrote: > > I'm sure I could move it, but as Chris asked, isn't it trivial to get > > this information anyway? Also, I'm kind of hesitant to put so much > > effort into compile-time performance issues when it doesn't even have > > partial (let alone full) functionality right now. We don't know what > > impact any of those optimizations have or if they are necessary yet. > > :-) > > It's something to keep in mind. Not critical right now if we are not > hoisting anything with implicit defs / uses. > Sounds good. :-)
> If we are keeping LICM before livevariables, we will have to compute > liveness in the BB's where the invariants are hoisted to. Now that I > think about it, we *cannot* use the register scavenger to do this > because it also depends on kill / dead markers on the operands. The > scavenger's job is not to add the kill / dead markers, it is to track > what registers are live at any point of the BB. This means you'll > have to walk the BB and track all physical register defs and uses in > the BB. > I see. Okay, so by the time I get to the point where I'm moving instructions that access physical registers, I should have the pass after LiveVariables... -bw _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
