diff --git a/include/llvm/Target/TargetSchedule.td b/include/llvm/Target/TargetSchedule.td
index 31e8b17..e22e67c 100644
--- a/include/llvm/Target/TargetSchedule.td
+++ b/include/llvm/Target/TargetSchedule.td
@@ -133,7 +133,8 @@
 }
 
 // NoItineraries - A marker that can be used by processors without schedule
-// info.
+// info. Subtargets using NoItineraries can bypass the scheduler's
+// expensive HazardRecognizer because no reservation table is needed.
 def NoItineraries : ProcessorItineraries<[], [], []>;
 
 // Processor itineraries with non-unit issue width. This allows issue
diff --git a/lib/Target/ARM/ARM.td b/lib/Target/ARM/ARM.td
index 9b0cb0c..d332d20 100644
--- a/lib/Target/ARM/ARM.td
+++ b/lib/Target/ARM/ARM.td
@@ -141,7 +141,7 @@
                                     FeatureAvoidPartialCPSR]>;
 
 class ProcNoItin<string Name, list<SubtargetFeature> Features>
- : Processor<Name, GenericItineraries, Features>;
+ : Processor<Name, NoItineraries, Features>;
 
 // V4 Processors.
 def : ProcNoItin<"generic",         []>;
diff --git a/lib/Target/ARM/ARMSchedule.td b/lib/Target/ARM/ARMSchedule.td
index 45486fd..b9a07f1 100644
--- a/lib/Target/ARM/ARMSchedule.td
+++ b/lib/Target/ARM/ARMSchedule.td
@@ -258,8 +258,6 @@
 //===----------------------------------------------------------------------===//
 // Processor instruction itineraries.
 
-def GenericItineraries : ProcessorItineraries<[], [], []>;
-
 include "ARMScheduleV6.td"
 include "ARMScheduleA8.td"
 include "ARMScheduleA9.td"
diff --git a/lib/Target/MBlaze/MBlaze.td b/lib/Target/MBlaze/MBlaze.td
index b4edff0..c288855 100644
--- a/lib/Target/MBlaze/MBlaze.td
+++ b/lib/Target/MBlaze/MBlaze.td
@@ -50,7 +50,7 @@
 // MBlaze processors supported.
 //===----------------------------------------------------------------------===//
 
-def : Processor<"mblaze",  MBlazeGenericItineraries, []>;
+def : Processor<"mblaze",  NoItineraries, []>;
 def : Processor<"mblaze3", MBlazePipe3Itineraries, []>;
 def : Processor<"mblaze5", MBlazePipe5Itineraries, []>;
 
diff --git a/lib/Target/MBlaze/MBlazeSchedule.td b/lib/Target/MBlaze/MBlazeSchedule.td
index 4a3ae5f..cd5691c 100644
--- a/lib/Target/MBlaze/MBlazeSchedule.td
+++ b/lib/Target/MBlaze/MBlazeSchedule.td
@@ -40,11 +40,6 @@
 def IIC_Pseudo : InstrItinClass;
 
 //===----------------------------------------------------------------------===//
-// MBlaze generic instruction itineraries.
-//===----------------------------------------------------------------------===//
-def MBlazeGenericItineraries : ProcessorItineraries<[], [], []>;
-
-//===----------------------------------------------------------------------===//
 // MBlaze instruction itineraries for three stage pipeline.
 //===----------------------------------------------------------------------===//
 include "MBlazeSchedule3.td"
diff --git a/utils/TableGen/SubtargetEmitter.cpp b/utils/TableGen/SubtargetEmitter.cpp
index 870b8ad..19b0550 100644
--- a/utils/TableGen/SubtargetEmitter.cpp
+++ b/utils/TableGen/SubtargetEmitter.cpp
@@ -422,15 +422,18 @@
     // Get processor itinerary name
     const std::string &Name = Proc->getName();
 
-    // Skip default
-    if (Name == "NoItineraries") continue;
-
-    // Create and expand processor itinerary to cover all itinerary classes
-    std::vector<InstrItinerary> ItinList;
-    ItinList.resize(NItinClasses);
-
     // Get itinerary data list
     std::vector<Record*> ItinDataList = Proc->getValueAsListOfDefs("IID");
+    std::vector<InstrItinerary> ItinList;
+
+    // Add an empty itinerary.
+    if (ItinDataList.empty()) {
+      ProcList.push_back(ItinList);
+      continue;
+    }
+
+    // Expand processor itinerary to cover all itinerary classes
+    ItinList.resize(NItinClasses);
 
     // For each itinerary data
     for (unsigned j = 0, M = ItinDataList.size(); j < M; j++) {
@@ -559,8 +562,6 @@
     const std::string &Name = Itin->getName();
 
     // Skip default
-    if (Name == "NoItineraries") continue;
-
     // Begin processor itinerary properties
     OS << "\n";
     OS << "static const llvm::InstrItineraryProps " << Name << "Props(\n";
@@ -570,42 +571,45 @@
     EmitItineraryProp(OS, Itin, "HighLatency", ' ');
     OS << ");\n";
 
-    // Begin processor itinerary table
-    OS << "\n";
-    OS << "static const llvm::InstrItinerary " << Name << "Entries"
-       << "[] = {\n";
-
     // For each itinerary class
     std::vector<InstrItinerary> &ItinList = *ProcListIter++;
-    assert(ItinList.size() == ItinClassList.size() && "bad itinerary");
-    for (unsigned j = 0, M = ItinList.size(); j < M; ++j) {
-      InstrItinerary &Intinerary = ItinList[j];
+    if (!ItinList.empty()) {
+      assert(ItinList.size() == ItinClassList.size() && "bad itinerary");
 
-      // Emit in the form of
-      // { firstStage, lastStage, firstCycle, lastCycle } // index
-      if (Intinerary.FirstStage == 0) {
-        OS << "  { 1, 0, 0, 0, 0 }";
-      } else {
-        OS << "  { " <<
-          Intinerary.NumMicroOps << ", " <<
-          Intinerary.FirstStage << ", " <<
-          Intinerary.LastStage << ", " <<
-          Intinerary.FirstOperandCycle << ", " <<
-          Intinerary.LastOperandCycle << " }";
+      // Begin processor itinerary table
+      OS << "\n";
+      OS << "static const llvm::InstrItinerary " << Name << "Entries"
+         << "[] = {\n";
+
+      for (unsigned j = 0, M = ItinList.size(); j < M; ++j) {
+        InstrItinerary &Intinerary = ItinList[j];
+
+        // Emit in the form of
+        // { firstStage, lastStage, firstCycle, lastCycle } // index
+        if (Intinerary.FirstStage == 0) {
+          OS << "  { 1, 0, 0, 0, 0 }";
+        } else {
+          OS << "  { " <<
+            Intinerary.NumMicroOps << ", " <<
+            Intinerary.FirstStage << ", " <<
+            Intinerary.LastStage << ", " <<
+            Intinerary.FirstOperandCycle << ", " <<
+            Intinerary.LastOperandCycle << " }";
+        }
+        OS << ", // " << j << " " << ItinClassList[j]->getName() << "\n";
       }
-
-      OS << ", // " << j << " " << ItinClassList[j]->getName() << "\n";
+      // End processor itinerary table
+      OS << "  { 1, ~0U, ~0U, ~0U, ~0U } // end marker\n";
+      OS << "};\n";
     }
-
-    // End processor itinerary table
-    OS << "  { 1, ~0U, ~0U, ~0U, ~0U } // end marker\n";
-    OS << "};\n";
-
     OS << '\n';
     OS << "static const llvm::InstrItinerarySubtargetValue "
        << Name << " = {\n";
     OS << "  &" << Name << "Props,\n";
-    OS << "  " << Name << "Entries\n";
+    if (ItinList.empty())
+      OS << "  0\n";
+    else
+      OS << "  " << Name << "Entries\n";
     OS << "};\n";
   }
 }