3 files changed, 28 insertions, 6 deletions
diff --git a/utils/TableGen/CodeGenTarget.cpp b/utils/TableGen/CodeGenTarget.cpp
index cf33fe6b1a..bc758b75cd 100644
--- a/utils/TableGen/CodeGenTarget.cpp
+++ b/utils/TableGen/CodeGenTarget.cpp
@@ -351,6 +351,18 @@ ComplexPattern::ComplexPattern(Record *R) {
            << "' on ComplexPattern '" << R->getName() << "'!\n";
       exit(1);
     }
+  
+  // Parse the attributes.  
+  Attributes = 0;
+  PropList = R->getValueAsListOfDefs("Attributes");
+  for (unsigned i = 0, e = PropList.size(); i != e; ++i)
+    if (PropList[i]->getName() == "CPAttrParentAsRoot") {
+      Attributes |= 1 << CPAttrParentAsRoot;
+    } else {
+      cerr << "Unsupported pattern attribute '" << PropList[i]->getName()
+           << "' on ComplexPattern '" << R->getName() << "'!\n";
+      exit(1);
+    }
 }
 
 //===----------------------------------------------------------------------===//
diff --git a/utils/TableGen/CodeGenTarget.h b/utils/TableGen/CodeGenTarget.h
index 922c2b41a1..a14f6303bd 100644
--- a/utils/TableGen/CodeGenTarget.h
+++ b/utils/TableGen/CodeGenTarget.h
@@ -42,6 +42,9 @@ enum SDNP {
   SDNPSideEffect
 };
 
+// ComplexPattern attributes.
+enum CPAttr { CPAttrParentAsRoot };
+
 /// getValueType - Return the MVT::ValueType that the specified TableGen record
 /// corresponds to.
 MVT::ValueType getValueType(Record *Rec);
@@ -172,7 +175,8 @@ class ComplexPattern {
   unsigned NumOperands;
   std::string SelectFunc;
   std::vector<Record*> RootNodes;
-  unsigned Properties;
+  unsigned Properties; // Node properties
+  unsigned Attributes; // Pattern attributes
 public:
   ComplexPattern() : NumOperands(0) {};
   ComplexPattern(Record *R);
@@ -184,7 +188,7 @@ public:
     return RootNodes;
   }
   bool hasProperty(enum SDNP Prop) const { return Properties & (1 << Prop); }
-
+  bool hasAttribute(enum CPAttr Attr) const { return Attributes & (1 << Attr); }
 };
 
 } // End llvm namespace
diff --git a/utils/TableGen/DAGISelEmitter.cpp b/utils/TableGen/DAGISelEmitter.cpp
index d685f701f0..1f568ad5ee 100644
--- a/utils/TableGen/DAGISelEmitter.cpp
+++ b/utils/TableGen/DAGISelEmitter.cpp
@@ -550,7 +550,7 @@ public:
           emitCheck(MaskPredicate + RootName + "0, cast<ConstantSDNode>(" +
                     RootName + "1), " + itostr(II->getValue()) + ")");
           
-          EmitChildMatchCode(N->getChild(0), N, RootName + utostr(0),
+          EmitChildMatchCode(N->getChild(0), N, RootName + utostr(0), RootName,
                              ChainSuffix + utostr(0), FoundChain);
           return;
         }
@@ -561,7 +561,7 @@ public:
       emitInit("SDOperand " + RootName + utostr(OpNo) + " = " +
                RootName + ".getOperand(" +utostr(OpNo) + ");");
 
-      EmitChildMatchCode(N->getChild(i), N, RootName + utostr(OpNo),
+      EmitChildMatchCode(N->getChild(i), N, RootName + utostr(OpNo), RootName,
                          ChainSuffix + utostr(OpNo), FoundChain);
     }
 
@@ -593,7 +593,8 @@ public:
   }
 
   void EmitChildMatchCode(TreePatternNode *Child, TreePatternNode *Parent,
-                          const std::string &RootName,
+                          const std::string &RootName, 
+                          const std::string &ParentRootName,
                           const std::string &ChainSuffix, bool &FoundChain) {
     if (!Child->isLeaf()) {
       // If it's not a leaf, recursively match.
@@ -649,7 +650,12 @@ public:
             emitCode("SDOperand " + ChainName + ";");
           }
           
-          std::string Code = Fn + "(N, ";
+          std::string Code = Fn + "(";
+          if (CP->hasAttribute(CPAttrParentAsRoot)) {
+            Code += ParentRootName + ", ";
+          } else {
+            Code += "N, ";
+          }
           if (CP->hasProperty(SDNPHasChain)) {
             std::string ParentName(RootName.begin(), RootName.end()-1);
             Code += ParentName + ", ";