[PATCH] D49401: TII: Generalize X86's isSafeToClobberEFLAGs

[Matthias Braun via Phabricator via llvm-commits]

MatzeB added a comment.

In https://reviews.llvm.org/D49401#1177039, @arsenm wrote:

> In https://reviews.llvm.org/D49401#1177010, @MatzeB wrote:
>
> > Also I'd generally recommend to rather look at LivePhysReg/LiveRegUnits for doing liveness queries post-ra. They can be more expensive but give more consistent results...
>
>
> I want to use this in an SSA pass, not post-RA


Fair enough. But `MachineBasicBlock::computeRegisterLiveness(TRI, Reg, I, 4) == LQR_Dead?` should work in machine SSA, shouldn't it?


https://reviews.llvm.org/D49401