Fix DEBUG logs in MachineLICM.

Summary:
MBBs don't necessarily have a name (in my experience, they almost never
do), in which case this logging is quite unhelpful.  The number seems to
work well.

Reviewers: iteratee

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D20533

llvm-svn: 270477

llvm/lib/CodeGen/MachineLICM.cpp

@@ -581,14 +581,14 @@ bool MachineLICM::IsGuaranteedToExecute(MachineBasicBlock *BB) {
 }
 
 void MachineLICM::EnterScope(MachineBasicBlock *MBB) {
-  DEBUG(dbgs() << "Entering: " << MBB->getName() << '\n');
+  DEBUG(dbgs() << "Entering BB#" << MBB->getNumber() << '\n');
 
   // Remember livein register pressure.
   BackTrace.push_back(RegPressure);
 }
 
 void MachineLICM::ExitScope(MachineBasicBlock *MBB) {
-  DEBUG(dbgs() << "Exiting: " << MBB->getName() << '\n');
+  DEBUG(dbgs() << "Exiting BB#" << MBB->getNumber() << '\n');
   BackTrace.pop_back();
 }
 
@@ -1317,12 +1317,10 @@ bool MachineLICM::Hoist(MachineInstr *MI, MachineBasicBlock *Preheader) {
   // terminator instructions.
   DEBUG({
       dbgs() << "Hoisting " << *MI;
-      if (Preheader->getBasicBlock())
-        dbgs() << " to MachineBasicBlock "
-               << Preheader->getName();
       if (MI->getParent()->getBasicBlock())
-        dbgs() << " from MachineBasicBlock "
-               << MI->getParent()->getName();
+        dbgs() << " from BB#" << MI->getParent()->getNumber();
+      if (Preheader->getBasicBlock())
+        dbgs() << " to BB#" << Preheader->getNumber();
       dbgs() << "\n";
     });