search for: foldmemoryoperandimp

Hi, I wonder if it would be possible to extend foldMemoryOperandImp() so that targets can check for liveness of a particular phys reg? The case I am thinking of is when the new instruction clobbers the CC reg, while the old one did not. In this case the new instruction can only become a replacement if the CC reg is known to be dead. The idea is that liveness o...

Hi, I wonder if live-in lists can be trusted to be accurate during register allocation / foldMemoryOperandImp(). On SystemZ, a compare register-register which has one of the registers spilled can fold that reload into a compare register-memory instruction. In order to do this also with the first (LHS) register, the operands must be swapped. This can only reasonably be done when all the CC users are in...

...und a reference to LiveIntervalAnalysis*. Patches welcome :) - Matthias > On Apr 27, 2016, at 11:38 AM, Jonas Paulsson via llvm-dev <llvm-dev at lists.llvm.org> wrote: > > ping. > > Either this can be implemented easily, or the current SystemZ optimization LAY -> AGSI in foldMemoryOperandImpl() should be removed, since this is actually illegal. > > /Jonas > > On 2016-04-15 12:53, Jonas Paulsson wrote: >> Hi, >> >> I wonder if it would be possible to extend foldMemoryOperandImp() so that targets can check for liveness of a particular phys reg? >>...