Split ISD::LABEL into ISD::DBG_LABEL and ISD::EH_LABEL, eliminating
the need for a flavor operand, and add a new SDNode subclass,
LabelSDNode, for use with them to eliminate the need for a label id
operand.

Change instruction selection to let these label nodes through
unmodified instead of creating copies of them. Teach the MachineInstr
emitter how to emit a MachineInstr directly from an ISD label node.

This avoids the need for allocating SDNodes for the label id and
flavor value, as well as SDNodes for each of the post-isel label,
label id, and label flavor.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52943 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/BranchFolding.cpp b/lib/CodeGen/BranchFolding.cpp
index f629ae7..6825bfb 100644
--- a/lib/CodeGen/BranchFolding.cpp
+++ b/lib/CodeGen/BranchFolding.cpp
@@ -114,12 +114,12 @@
   while (!MBB->succ_empty())
     MBB->removeSuccessor(MBB->succ_end()-1);
   
-  // If there is DWARF info to active, check to see if there are any LABEL
+  // If there is DWARF info to active, check to see if there are any DBG_LABEL
   // records in the basic block.  If so, unregister them from MachineModuleInfo.
   if (MMI && !MBB->empty()) {
     for (MachineBasicBlock::iterator I = MBB->begin(), E = MBB->end();
          I != E; ++I) {
-      if ((unsigned)I->getOpcode() == TargetInstrInfo::LABEL) {
+      if ((unsigned)I->getOpcode() == TargetInstrInfo::DBG_LABEL) {
         // The label ID # is always operand #0, an immediate.
         MMI->InvalidateLabel(I->getOperand(0).getImm());
       }