tblgen: Mechanically move dynamic_cast<> to dyn_cast<>.

Some of these dyn_cast<>'s would be better phrased as isa<> or cast<>.
That will happen in a future patch.

There are also two dyn_cast_or_null<>'s slipped in instead of
dyn_cast<>'s, since they were causing crashes with just dyn_cast<>.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165646 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/PseudoLoweringEmitter.cpp b/utils/TableGen/PseudoLoweringEmitter.cpp
index 1896a7b..b0241c7 100644
--- a/utils/TableGen/PseudoLoweringEmitter.cpp
+++ b/utils/TableGen/PseudoLoweringEmitter.cpp
@@ -74,7 +74,7 @@
                      IndexedMap<OpData> &OperandMap, unsigned BaseIdx) {
   unsigned OpsAdded = 0;
   for (unsigned i = 0, e = Dag->getNumArgs(); i != e; ++i) {
-    if (DefInit *DI = dynamic_cast<DefInit*>(Dag->getArg(i))) {
+    if (DefInit *DI = dyn_cast<DefInit>(Dag->getArg(i))) {
       // Physical register reference. Explicit check for the special case
       // "zero_reg" definition.
       if (DI->getDef()->isSubClassOf("Register") ||
@@ -100,11 +100,11 @@
       for (unsigned I = 0, E = Insn.Operands[i].MINumOperands; I != E; ++I)
         OperandMap[BaseIdx + i + I].Kind = OpData::Operand;
       OpsAdded += Insn.Operands[i].MINumOperands;
-    } else if (IntInit *II = dynamic_cast<IntInit*>(Dag->getArg(i))) {
+    } else if (IntInit *II = dyn_cast<IntInit>(Dag->getArg(i))) {
       OperandMap[BaseIdx + i].Kind = OpData::Imm;
       OperandMap[BaseIdx + i].Data.Imm = II->getValue();
       ++OpsAdded;
-    } else if (DagInit *SubDag = dynamic_cast<DagInit*>(Dag->getArg(i))) {
+    } else if (DagInit *SubDag = dyn_cast<DagInit>(Dag->getArg(i))) {
       // Just add the operands recursively. This is almost certainly
       // a constant value for a complex operand (> 1 MI operand).
       unsigned NewOps =
@@ -127,7 +127,7 @@
   assert(Dag && "Missing result instruction in pseudo expansion!");
   DEBUG(dbgs() << "  Result: " << *Dag << "\n");
 
-  DefInit *OpDef = dynamic_cast<DefInit*>(Dag->getOperator());
+  DefInit *OpDef = dyn_cast<DefInit>(Dag->getOperator());
   if (!OpDef)
     throw TGError(Rec->getLoc(), Rec->getName() +
                   " has unexpected operator type!");