1 files changed, 22 insertions, 8 deletions

diff --git a/utils/TableGen/Record.cpp b/utils/TableGen/Record.cpp
index b9facb4..55c9989 100644
--- a/utils/TableGen/Record.cpp
+++ b/utils/TableGen/Record.cpp
@@ -1108,12 +1108,15 @@ RecTy *VarInit::getFieldType(const std::string &FieldName) const {
   return 0;
 }
 
-Init *VarInit::getFieldInit(Record &R, const std::string &FieldName) const {
+Init *VarInit::getFieldInit(Record &R, const RecordVal *RV,
+                            const std::string &FieldName) const {
   if (dynamic_cast<RecordRecTy*>(getType()))
-    if (const RecordVal *RV = R.getValue(VarName)) {
-      Init *TheInit = RV->getValue();
+    if (const RecordVal *Val = R.getValue(VarName)) {
+      if (RV != Val && (RV || dynamic_cast<UnsetInit*>(Val->getValue())))
+        return 0;
+      Init *TheInit = Val->getValue();
       assert(TheInit != this && "Infinite loop detected!");
-      if (Init *I = TheInit->getFieldInit(R, FieldName))
+      if (Init *I = TheInit->getFieldInit(R, RV, FieldName))
         return I;
       else
         return 0;
@@ -1174,7 +1177,8 @@ RecTy *DefInit::getFieldType(const std::string &FieldName) const {
   return 0;
 }
 
-Init *DefInit::getFieldInit(Record &R, const std::string &FieldName) const {
+Init *DefInit::getFieldInit(Record &R, const RecordVal *RV,
+                            const std::string &FieldName) const {
   return Def->getValue(FieldName)->getValue();
 }
 
@@ -1185,7 +1189,7 @@ std::string DefInit::getAsString() const {
 
 Init *FieldInit::resolveBitReference(Record &R, const RecordVal *RV,
                                      unsigned Bit) {
-  if (Init *BitsVal = Rec->getFieldInit(R, FieldName))
+  if (Init *BitsVal = Rec->getFieldInit(R, RV, FieldName))
     if (BitsInit *BI = dynamic_cast<BitsInit*>(BitsVal)) {
       assert(Bit < BI->getNumBits() && "Bit reference out of range!");
       Init *B = BI->getBit(Bit);
@@ -1198,7 +1202,7 @@ Init *FieldInit::resolveBitReference(Record &R, const RecordVal *RV,
 
 Init *FieldInit::resolveListElementReference(Record &R, const RecordVal *RV,
                                              unsigned Elt) {
-  if (Init *ListVal = Rec->getFieldInit(R, FieldName))
+  if (Init *ListVal = Rec->getFieldInit(R, RV, FieldName))
     if (ListInit *LI = dynamic_cast<ListInit*>(ListVal)) {
       if (Elt >= LI->getSize()) return 0;
       Init *E = LI->getElement(Elt);
@@ -1215,7 +1219,7 @@ Init *FieldInit::resolveListElementReference(Record &R, const RecordVal *RV,
 Init *FieldInit::resolveReferences(Record &R, const RecordVal *RV) {
   Init *NewRec = RV ? Rec->resolveReferences(R, RV) : Rec;
 
-  Init *BitsVal = NewRec->getFieldInit(R, FieldName);
+  Init *BitsVal = NewRec->getFieldInit(R, RV, FieldName);
   if (BitsVal) {
     Init *BVR = BitsVal->resolveReferences(R, RV);
     return BVR->isComplete() ? BVR : this;
@@ -1303,6 +1307,16 @@ void Record::resolveReferencesTo(const RecordVal *RV) {
   }
 }
 
+RecordVal *Record::getDottedValue(StringRef Name) {
+  size_t pos = Name.find('.');
+  if (pos == StringRef::npos)
+    return getValue(Name);
+  RecordVal *RV = getValue(Name.substr(0, pos));
+  if (!RV) return 0;
+  DefInit *DI = dynamic_cast<DefInit*>(RV->getValue());
+  if (!DI) return 0;
+  return DI->getDef()->getDottedValue(Name.substr(pos+1));
+}
 
 void Record::dump() const { errs() << *this; }