Rename ISD::LOCATION to ISD::DBG_STOPPOINT to better reflect its
purpose, and give it a custom SDNode subclass so that it doesn't
need to have line number, column number, filename string, and
directory string, all existing as individual SDNodes to be the
operands.

This was the only user of ISD::STRING, StringSDNode, etc., so
remove those and some associated code.

This makes stop-points considerably easier to read in
-view-legalize-dags output, and reduces overhead (creating new
nodes and copying std::strings into them) on code containing
debugging information.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52924 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 3d01bb2..3665ee0 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -849,7 +849,6 @@
   case ISD::VALUETYPE:
   case ISD::SRCVALUE:
   case ISD::MEMOPERAND:
-  case ISD::STRING:
   case ISD::CONDCODE:
   case ISD::ARG_FLAGS:
     // Primitives must all be legal.
@@ -1075,11 +1074,11 @@
     return Result.getValue(Op.ResNo);
   }    
 
-  case ISD::LOCATION:
-    assert(Node->getNumOperands() == 5 && "Invalid LOCATION node!");
+  case ISD::DBG_STOPPOINT:
+    assert(Node->getNumOperands() == 1 && "Invalid DBG_STOPPOINT node!");
     Tmp1 = LegalizeOp(Node->getOperand(0));  // Legalize the input chain.
     
-    switch (TLI.getOperationAction(ISD::LOCATION, MVT::Other)) {
+    switch (TLI.getOperationAction(ISD::DBG_STOPPOINT, MVT::Other)) {
     case TargetLowering::Promote:
     default: assert(0 && "This action is not supported yet!");
     case TargetLowering::Expand: {
@@ -1087,26 +1086,22 @@
       bool useDEBUG_LOC = TLI.isOperationLegal(ISD::DEBUG_LOC, MVT::Other);
       bool useLABEL = TLI.isOperationLegal(ISD::LABEL, MVT::Other);
       
+      const DbgStopPointSDNode *DSP = cast<DbgStopPointSDNode>(Node);
       if (MMI && (useDEBUG_LOC || useLABEL)) {
-        const std::string &FName =
-          cast<StringSDNode>(Node->getOperand(3))->getValue();
-        const std::string &DirName = 
-          cast<StringSDNode>(Node->getOperand(4))->getValue();
-        unsigned SrcFile = MMI->RecordSource(DirName, FName);
+        const CompileUnitDesc *CompileUnit = DSP->getCompileUnit();
+        unsigned SrcFile = MMI->RecordSource(CompileUnit);
 
         SmallVector<SDOperand, 8> Ops;
         Ops.push_back(Tmp1);  // chain
-        SDOperand LineOp = Node->getOperand(1);
-        SDOperand ColOp = Node->getOperand(2);
+        unsigned Line = DSP->getLine();
+        unsigned Col = DSP->getColumn();
         
         if (useDEBUG_LOC) {
-          Ops.push_back(LineOp);  // line #
-          Ops.push_back(ColOp);  // col #
+          Ops.push_back(DAG.getConstant(Line, MVT::i32));  // line #
+          Ops.push_back(DAG.getConstant(Col, MVT::i32));   // col #
           Ops.push_back(DAG.getConstant(SrcFile, MVT::i32));  // source file id
           Result = DAG.getNode(ISD::DEBUG_LOC, MVT::Other, &Ops[0], Ops.size());
         } else {
-          unsigned Line = cast<ConstantSDNode>(LineOp)->getValue();
-          unsigned Col = cast<ConstantSDNode>(ColOp)->getValue();
           unsigned ID = MMI->RecordSourceLine(Line, Col, SrcFile);
           Ops.push_back(DAG.getConstant(ID, MVT::i32));
           Ops.push_back(DAG.getConstant(0, MVT::i32)); // a debug label