diff --git a/lib/TableGen/TGParser.cpp b/lib/TableGen/TGParser.cpp
index 085136d4815..d864b4f69d8 100644
--- a/lib/TableGen/TGParser.cpp
+++ b/lib/TableGen/TGParser.cpp
@@ -636,7 +636,7 @@ RecTy *TGParser::ParseType() {
 ///  IDValue ::= ID [multiclass template argument]
 ///  IDValue ::= ID [def name]
 ///
-Init *TGParser::ParseIDValue(Record *CurRec) {
+Init *TGParser::ParseIDValue(Record *CurRec, IDParseMode Mode) {
   assert(Lex.getCode() == tgtok::Id && "Expected ID in ParseIDValue");
   std::string Name = Lex.getCurStrVal();
   SMLoc Loc = Lex.getLoc();
@@ -647,7 +647,8 @@ Init *TGParser::ParseIDValue(Record *CurRec) {
 /// ParseIDValue - This is just like ParseIDValue above, but it assumes the ID
 /// has already been read.
 Init *TGParser::ParseIDValue(Record *CurRec,
-                             const std::string &Name, SMLoc NameLoc) {
+                             const std::string &Name, SMLoc NameLoc,
+                             IDParseMode Mode) {
   if (CurRec) {
     if (const RecordVal *RV = CurRec->getValue(Name))
       return VarInit::get(Name, RV->getType());
@@ -1048,7 +1049,8 @@ RecTy *TGParser::ParseOperatorType() {
 ///   SimpleValue ::= SRLTOK '(' Value ',' Value ')'
 ///   SimpleValue ::= STRCONCATTOK '(' Value ',' Value ')'
 ///
-Init *TGParser::ParseSimpleValue(Record *CurRec, RecTy *ItemType) {
+Init *TGParser::ParseSimpleValue(Record *CurRec, RecTy *ItemType,
+                                 IDParseMode Mode) {
   Init *R = 0;
   switch (Lex.getCode()) {
   default: TokError("Unknown token when parsing a value"); break;
@@ -1078,7 +1080,7 @@ Init *TGParser::ParseSimpleValue(Record *CurRec, RecTy *ItemType) {
     SMLoc NameLoc = Lex.getLoc();
     std::string Name = Lex.getCurStrVal();
     if (Lex.Lex() != tgtok::less)  // consume the Id.
-      return ParseIDValue(CurRec, Name, NameLoc);    // Value ::= IDValue
+      return ParseIDValue(CurRec, Name, NameLoc, Mode);    // Value ::= IDValue
 
     // Value ::= ID '<' ValueListNE '>'
     if (Lex.Lex() == tgtok::greater) {
@@ -1312,8 +1314,8 @@ Init *TGParser::ParseSimpleValue(Record *CurRec, RecTy *ItemType) {
 ///   ValueSuffix ::= '[' BitList ']'
 ///   ValueSuffix ::= '.' ID
 ///
-Init *TGParser::ParseValue(Record *CurRec, RecTy *ItemType) {
-  Init *Result = ParseSimpleValue(CurRec, ItemType);
+Init *TGParser::ParseValue(Record *CurRec, RecTy *ItemType, IDParseMode Mode) {
+  Init *Result = ParseSimpleValue(CurRec, ItemType, Mode);
   if (Result == 0) return 0;
 
   // Parse the suffixes now if present.
diff --git a/lib/TableGen/TGParser.h b/lib/TableGen/TGParser.h
index da52da2f798..18aeae22e29 100644
--- a/lib/TableGen/TGParser.h
+++ b/lib/TableGen/TGParser.h
@@ -53,6 +53,17 @@ class TGParser {
 
   // Record tracker
   RecordKeeper &Records;
+
+  // A "named boolean" indicating how to parse identifiers.  Usually
+  // identifiers map to some existing object but in special cases
+  // (e.g. parsing def names) no such object exists yet because we are
+  // in the middle of creating in.  For those situations, allow the
+  // parser to ignore missing object errors.
+  enum IDParseMode {
+    ParseValueMode, // We are parsing a value we expect to look up.
+    ParseNameMode // We are parsing a name of an object that does not yet exist.
+  };
+
 public:
   TGParser(SourceMgr &SrcMgr, RecordKeeper &records) : 
     Lex(SrcMgr), CurMultiClass(0), Records(records) {}
@@ -118,10 +129,13 @@ private:  // Parser methods.
   SubClassReference ParseSubClassReference(Record *CurRec, bool isDefm);
   SubMultiClassReference ParseSubMultiClassReference(MultiClass *CurMC);
 
-  Init *ParseIDValue(Record *CurRec);
-  Init *ParseIDValue(Record *CurRec, const std::string &Name, SMLoc NameLoc);
-  Init *ParseSimpleValue(Record *CurRec, RecTy *ItemType = 0);
-  Init *ParseValue(Record *CurRec, RecTy *ItemType = 0);
+  Init *ParseIDValue(Record *CurRec, IDParseMode Mode = ParseValueMode);
+  Init *ParseIDValue(Record *CurRec, const std::string &Name, SMLoc NameLoc,
+                     IDParseMode Mode = ParseValueMode);
+  Init *ParseSimpleValue(Record *CurRec, RecTy *ItemType = 0,
+                         IDParseMode Mode = ParseValueMode);
+  Init *ParseValue(Record *CurRec, RecTy *ItemType = 0,
+                   IDParseMode Mode = ParseValueMode);
   std::vector<Init*> ParseValueList(Record *CurRec, Record *ArgsRec = 0, RecTy *EltTy = 0);
   std::vector<std::pair<llvm::Init*, std::string> > ParseDagArgList(Record *);
   bool ParseOptionalRangeList(std::vector<unsigned> &Ranges);