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

utils/TableGen/InstrInfoEmitter.cpp

@@ -279,7 +279,9 @@ void InstrInfoEmitter::emitShiftedValue(Record *R, StringInit *Val,
     // This isn't an error if this is a builtin instruction.
     if (R->getName() != "PHI" &&
         R->getName() != "INLINEASM" &&
-        R->getName() != "LABEL" &&
+        R->getName() != "DBG_LABEL" &&
+        R->getName() != "EH_LABEL" &&
+        R->getName() != "GC_LABEL" &&
         R->getName() != "DECLARE" &&
         R->getName() != "EXTRACT_SUBREG" &&
         R->getName() != "INSERT_SUBREG" &&