[PATCH] D14632: [MachineSink] Don't break ImplicitNulls

[David Majnemer via llvm-commits]

majnemer added inline comments.

================
Comment at: lib/CodeGen/MachineSink.cpp:694
@@ +693,3 @@
+  auto *PredMBB = *MBB->pred_begin();
+  auto *PredBB = PredMBB->getBasicBlock();
+
----------------
sanjoy wrote:
> majnemer wrote:
> > Can't `getBasicBlock` fail?  IIRC, `MachineBasicBlock`s aren't obligated to map back to a `BasicBlock`.
> I think the failure mode is to return `nullptr`, which should be caught by the check below.
Ah, my eyes didn't see it.  Sorry for the noise.


http://reviews.llvm.org/D14632