Switch all register list clients to the new MC*Iterator interface.

No functional change intended.

Sorry for the churn. The iterator classes are supposed to help avoid
giant commits like this one in the future. The TableGen-produced
register lists are getting quite large, and it may be necessary to
change the table representation.

This makes it possible to do so without changing all clients (again).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157854 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/ExecutionDepsFix.cpp

@@ -666,7 +666,8 @@ bool ExeDepsFix::runOnMachineFunction(MachineFunction &mf) {
     // or -1.
     AliasMap.resize(TRI->getNumRegs(), -1);
     for (unsigned i = 0, e = RC->getNumRegs(); i != e; ++i)
-      for (const uint16_t *AI = TRI->getOverlaps(RC->getRegister(i)); *AI; ++AI)
+      for (MCRegAliasIterator AI(RC->getRegister(i), TRI, true);
+           AI.isValid(); ++AI)
         AliasMap[*AI] = i;
   }