Add MachineBasicBlock::getName, and use it in place of getBasicBlock()->getName.

Fix debug code that assumes getBasicBlock never returns NULL.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89428 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/MachineLICM.cpp

@@ -487,10 +487,10 @@ void MachineLICM::Hoist(MachineInstr *MI) {
       errs() << "Hoisting " << *MI;
       if (CurPreheader->getBasicBlock())
         errs() << " to MachineBasicBlock "
-               << CurPreheader->getBasicBlock()->getName();
+               << CurPreheader->getName();
       if (MI->getParent()->getBasicBlock())
         errs() << " from MachineBasicBlock "
-               << MI->getParent()->getBasicBlock()->getName();
+               << MI->getParent()->getName();
       errs() << "\n";
     });