- Added MCSubtargetInfo to capture subtarget features and scheduling

  itineraries.
- Refactor TargetSubtarget to be based on MCSubtargetInfo.
- Change tablegen generated subtarget info to initialize MCSubtargetInfo
  and hide more details from targets.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134257 91177308-0d34-0410-b5e6-96231b3b80d8

33 files changed, 402 insertions, 102 deletions

diff --git a/include/llvm/MC/MCSubtargetInfo.h b/include/llvm/MC/MCSubtargetInfo.h
new file mode 100644
index 0000000..d991f42
--- /dev/null
+++ b/include/llvm/MC/MCSubtargetInfo.h
@@ -0,0 +1,61 @@
+//==-- llvm/MC/MCSubtargetInfo.h - Subtarget Information ---------*- C++ -*-==//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file describes the subtarget options of a Target machine.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCSUBTARGET_H
+#define LLVM_MC_MCSUBTARGET_H
+
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/MC/MCInstrItineraries.h"
+
+namespace llvm {
+
+class StringRef;
+
+//===----------------------------------------------------------------------===//
+///
+/// MCSubtargetInfo - Generic base class for all target subtargets.
+///
+class MCSubtargetInfo {
+  const SubtargetFeatureKV *ProcFeatures;  // Processor feature list
+  const SubtargetFeatureKV *ProcDesc;  // Processor descriptions
+  const SubtargetInfoKV *ProcItins;    // Scheduling itineraries
+  const InstrStage *Stages;            // Instruction stages
+  const unsigned *OperandCycles;       // Operand cycles
+  const unsigned *ForwardingPathes;    // Forwarding pathes
+  unsigned NumFeatures;                // Number of processor features
+  unsigned NumProcs;                   // Number of processors
+    
+public:
+  void InitMCSubtargetInfo(const SubtargetFeatureKV *PF,
+                           const SubtargetFeatureKV *PD,
+                           const SubtargetInfoKV *PI, const InstrStage *IS,
+                           const unsigned *OC, const unsigned *FP,
+                           unsigned NF, unsigned NP) {
+    ProcFeatures = PF;
+    ProcDesc = PD;
+    ProcItins = PI;
+    Stages = IS;
+    OperandCycles = OC;
+    ForwardingPathes = FP;
+    NumFeatures = NF;
+    NumProcs = NP;
+  }
+
+  /// getInstrItineraryForCPU - Get scheduling itinerary of a CPU.
+  ///
+  InstrItineraryData getInstrItineraryForCPU(StringRef CPU) const;
+};
+
+} // End llvm namespace
+
+#endif
diff --git a/include/llvm/Target/TargetSubtarget.h b/include/llvm/Target/TargetSubtarget.h
index 22b09ba..5127a62 100644
--- a/include/llvm/Target/TargetSubtarget.h
+++ b/include/llvm/Target/TargetSubtarget.h
@@ -14,6 +14,7 @@
 #ifndef LLVM_TARGET_TARGETSUBTARGET_H
 #define LLVM_TARGET_TARGETSUBTARGET_H
 
+#include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/Target/TargetMachine.h"
 
 namespace llvm {
@@ -29,7 +30,7 @@ template <typename T> class SmallVectorImpl;
 /// Target-specific options that control code generation and printing should
 /// be exposed through a TargetSubtarget-derived class.
 ///
-class TargetSubtarget {
+class TargetSubtarget : public MCSubtargetInfo {
   TargetSubtarget(const TargetSubtarget&);   // DO NOT IMPLEMENT
   void operator=(const TargetSubtarget&);  // DO NOT IMPLEMENT
 protected: // Can only create subclasses...
diff --git a/lib/MC/CMakeLists.txt b/lib/MC/CMakeLists.txt
index 00e534f..22afa7e 100644
--- a/lib/MC/CMakeLists.txt
+++ b/lib/MC/CMakeLists.txt
@@ -28,6 +28,7 @@ add_llvm_library(LLVMMC
   MCSectionELF.cpp
   MCSectionMachO.cpp
   MCStreamer.cpp
+  MCSubtargetInfo.cpp
   MCSymbol.cpp
   MCValue.cpp
   MCWin64EH.cpp
diff --git a/lib/MC/MCSubtargetInfo.cpp b/lib/MC/MCSubtargetInfo.cpp
new file mode 100644
index 0000000..c401b7e
--- /dev/null
+++ b/lib/MC/MCSubtargetInfo.cpp
@@ -0,0 +1,44 @@
+//===-- MCSubtargetInfo.cpp - Subtarget Information -----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/MC/MCInstrItineraries.h"
+#include "llvm/MC/SubtargetFeature.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+
+using namespace llvm;
+
+InstrItineraryData
+MCSubtargetInfo::getInstrItineraryForCPU(StringRef CPU) const {
+  assert(ProcItins && "Instruction itineraries information not available!");
+
+#ifndef NDEBUG
+  for (size_t i = 1; i < NumProcs; i++) {
+    assert(strcmp(ProcItins[i - 1].Key, ProcItins[i].Key) < 0 &&
+           "Itineraries table is not sorted");
+  }
+#endif
+
+  // Find entry
+  SubtargetInfoKV KV;
+  KV.Key = CPU.data();
+  const SubtargetInfoKV *Found =
+    std::lower_bound(ProcItins, ProcItins+NumProcs, KV);
+  if (Found == ProcItins+NumProcs || StringRef(Found->Key) != CPU) {
+    errs() << "'" << CPU
+           << "' is not a recognized processor for this target"
+           << " (ignoring processor)\n";
+    return InstrItineraryData();
+  }
+
+  return InstrItineraryData(Stages, OperandCycles, ForwardingPathes,
+                            (InstrItinerary *)Found->Value);
+}
diff --git a/lib/Target/ARM/ARMSubtarget.cpp b/lib/Target/ARM/ARMSubtarget.cpp
index 694b313..01acde0 100644
--- a/lib/Target/ARM/ARMSubtarget.cpp
+++ b/lib/Target/ARM/ARMSubtarget.cpp
@@ -12,11 +12,17 @@
 //===----------------------------------------------------------------------===//
 
 #include "ARMSubtarget.h"
-#include "ARMGenSubtarget.inc"
 #include "ARMBaseRegisterInfo.h"
 #include "llvm/GlobalValue.h"
+#include "llvm/Target/TargetSubtarget.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/ADT/SmallVector.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "ARMGenSubtarget.inc"
+
 using namespace llvm;
 
 static cl::opt<bool>
@@ -32,7 +38,8 @@ StrictAlign("arm-strict-align", cl::Hidden,
 
 ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
                            const std::string &FS, bool isT)
-  : ARMArchVersion(V4)
+  : ARMGenSubtargetInfo()
+  , ARMArchVersion(V4)
   , ARMProcFamily(Others)
   , ARMFPUType(None)
   , UseNEONForSinglePrecisionFP(false)
@@ -130,6 +137,9 @@ ARMSubtarget::ARMSubtarget(const std::string &TT, const std::string &CPU,
     FSWithArch = FSWithArch + "," + FS;
   ParseSubtargetFeatures(FSWithArch, CPUString);
 
+  // Initialize scheduling itinerary for the specified CPU.
+  InstrItins = getInstrItineraryForCPU(CPUString);
+
   // After parsing Itineraries, set ItinData.IssueWidth.
   computeIssueWidth();
 
diff --git a/lib/Target/ARM/ARMSubtarget.h b/lib/Target/ARM/ARMSubtarget.h
index 7c93173..fbe8322 100644
--- a/lib/Target/ARM/ARMSubtarget.h
+++ b/lib/Target/ARM/ARMSubtarget.h
@@ -19,10 +19,13 @@
 #include "llvm/ADT/Triple.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "ARMGenSubtarget.inc"
+
 namespace llvm {
 class GlobalValue;
 
-class ARMSubtarget : public TargetSubtarget {
+class ARMSubtarget : public ARMGenSubtargetInfo {
 protected:
   enum ARMArchEnum {
     V4, V4T, V5T, V5TE, V6, V6M, V6T2, V7A, V7M
diff --git a/lib/Target/Alpha/AlphaSubtarget.cpp b/lib/Target/Alpha/AlphaSubtarget.cpp
index 7080327..5ed2d31 100644
--- a/lib/Target/Alpha/AlphaSubtarget.cpp
+++ b/lib/Target/Alpha/AlphaSubtarget.cpp
@@ -14,15 +14,24 @@
 #include "AlphaSubtarget.h"
 #include "Alpha.h"
 #include "AlphaGenSubtarget.inc"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "AlphaGenSubtarget.inc"
+
 using namespace llvm;
 
 AlphaSubtarget::AlphaSubtarget(const std::string &TT, const std::string &CPU,
                                const std::string &FS)
-  : HasCT(false) {
+  : AlphaGenSubtargetInfo(), HasCT(false) {
   std::string CPUName = CPU;
   if (CPUName.empty())
     CPUName = "generic";
 
   // Parse features string.
   ParseSubtargetFeatures(FS, CPUName);
+
+  // Initialize scheduling itinerary for the specified CPU.
+  InstrItins = getInstrItineraryForCPU(CPUName);
 }
diff --git a/lib/Target/Alpha/AlphaSubtarget.h b/lib/Target/Alpha/AlphaSubtarget.h
index b1ccf26..0bd161c 100644
--- a/lib/Target/Alpha/AlphaSubtarget.h
+++ b/lib/Target/Alpha/AlphaSubtarget.h
@@ -18,9 +18,12 @@
 #include "llvm/MC/MCInstrItineraries.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "AlphaGenSubtarget.inc"
+
 namespace llvm {
 
-class AlphaSubtarget : public TargetSubtarget {
+class AlphaSubtarget : public AlphaGenSubtargetInfo {
 protected:
 
   bool HasCT;
diff --git a/lib/Target/Blackfin/BlackfinSubtarget.cpp b/lib/Target/Blackfin/BlackfinSubtarget.cpp
index 5092026..f0328e0 100644
--- a/lib/Target/Blackfin/BlackfinSubtarget.cpp
+++ b/lib/Target/Blackfin/BlackfinSubtarget.cpp
@@ -12,6 +12,10 @@
 //===----------------------------------------------------------------------===//
 
 #include "BlackfinSubtarget.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
 #include "BlackfinGenSubtarget.inc"
 
 using namespace llvm;
@@ -19,7 +23,7 @@ using namespace llvm;
 BlackfinSubtarget::BlackfinSubtarget(const std::string &TT,
                                      const std::string &CPU,
                                      const std::string &FS)
-  : sdram(false),
+  : BlackfinGenSubtargetInfo(), sdram(false),
     icplb(false),
     wa_mi_shift(false),
     wa_csync(false),
diff --git a/lib/Target/Blackfin/BlackfinSubtarget.h b/lib/Target/Blackfin/BlackfinSubtarget.h
index a1a09ec..fecd035 100644
--- a/lib/Target/Blackfin/BlackfinSubtarget.h
+++ b/lib/Target/Blackfin/BlackfinSubtarget.h
@@ -17,9 +17,12 @@
 #include "llvm/Target/TargetSubtarget.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "BlackfinGenSubtarget.inc"
+
 namespace llvm {
 
-  class BlackfinSubtarget : public TargetSubtarget {
+  class BlackfinSubtarget : public BlackfinGenSubtargetInfo {
     bool sdram;
     bool icplb;
     bool wa_mi_shift;
diff --git a/lib/Target/CellSPU/SPUSubtarget.cpp b/lib/Target/CellSPU/SPUSubtarget.cpp
index a1a9f51..5128767 100644
--- a/lib/Target/CellSPU/SPUSubtarget.cpp
+++ b/lib/Target/CellSPU/SPUSubtarget.cpp
@@ -13,14 +13,19 @@
 
 #include "SPUSubtarget.h"
 #include "SPU.h"
-#include "SPUGenSubtarget.inc"
 #include "llvm/ADT/SmallVector.h"
 #include "SPURegisterInfo.h"
 
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "SPUGenSubtarget.inc"
+
 using namespace llvm;
 
 SPUSubtarget::SPUSubtarget(const std::string &TT, const std::string &CPU,
                            const std::string &FS) :
+  SPUGenSubtargetInfo(),
   StackAlignment(16),
   ProcDirective(SPU::DEFAULT_PROC),
   UseLargeMem(false)
@@ -31,6 +36,9 @@ SPUSubtarget::SPUSubtarget(const std::string &TT, const std::string &CPU,
 
   // Parse features string.
   ParseSubtargetFeatures(FS, default_cpu);
+
+  // Initialize scheduling itinerary for the specified CPU.
+  InstrItins = getInstrItineraryForCPU(default_cpu);
 }
 
 /// SetJITMode - This is called to inform the subtarget info that we are
diff --git a/lib/Target/CellSPU/SPUSubtarget.h b/lib/Target/CellSPU/SPUSubtarget.h
index 69a60db..2e5934b 100644
--- a/lib/Target/CellSPU/SPUSubtarget.h
+++ b/lib/Target/CellSPU/SPUSubtarget.h
@@ -18,6 +18,9 @@
 #include "llvm/MC/MCInstrItineraries.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "SPUGenSubtarget.inc"
+
 namespace llvm {
   class GlobalValue;
 
@@ -28,7 +31,7 @@ namespace llvm {
     };
   }
     
-  class SPUSubtarget : public TargetSubtarget {
+  class SPUSubtarget : public SPUGenSubtargetInfo {
   protected:
     /// stackAlignment - The minimum alignment known to hold of the stack frame
     /// on entry to the function and which must be maintained by every function.
diff --git a/lib/Target/MBlaze/MBlazeSubtarget.cpp b/lib/Target/MBlaze/MBlazeSubtarget.cpp
index 034b5ce..0ba0bea 100644
--- a/lib/Target/MBlaze/MBlazeSubtarget.cpp
+++ b/lib/Target/MBlaze/MBlazeSubtarget.cpp
@@ -14,13 +14,19 @@
 #include "MBlazeSubtarget.h"
 #include "MBlaze.h"
 #include "MBlazeRegisterInfo.h"
-#include "MBlazeGenSubtarget.inc"
 #include "llvm/Support/CommandLine.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "MBlazeGenSubtarget.inc"
+
 using namespace llvm;
 
 MBlazeSubtarget::MBlazeSubtarget(const std::string &TT,
                                  const std::string &CPU,
                                  const std::string &FS):
+  MBlazeGenSubtargetInfo(),
   HasBarrel(false), HasDiv(false), HasMul(false), HasPatCmp(false),
   HasFPU(false), HasMul64(false), HasSqrt(false)
 {
@@ -35,6 +41,9 @@ MBlazeSubtarget::MBlazeSubtarget(const std::string &TT,
   HasItin = CPUName != "mblaze";
   DEBUG(dbgs() << "CPU " << CPUName << "(" << HasItin << ")\n");
 
+  // Initialize scheduling itinerary for the specified CPU.
+  InstrItins = getInstrItineraryForCPU(CPUName);
+
   // Compute the issue width of the MBlaze itineraries
   computeIssueWidth();
 }
diff --git a/lib/Target/MBlaze/MBlazeSubtarget.h b/lib/Target/MBlaze/MBlazeSubtarget.h
index f5e0b4c..63acee2 100644
--- a/lib/Target/MBlaze/MBlazeSubtarget.h
+++ b/lib/Target/MBlaze/MBlazeSubtarget.h
@@ -18,9 +18,12 @@
 #include "llvm/MC/MCInstrItineraries.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "MBlazeGenSubtarget.inc"
+
 namespace llvm {
 
-class MBlazeSubtarget : public TargetSubtarget {
+class MBlazeSubtarget : public MBlazeGenSubtargetInfo {
 
 protected:
   bool HasBarrel;
diff --git a/lib/Target/MSP430/MSP430Subtarget.cpp b/lib/Target/MSP430/MSP430Subtarget.cpp
index a257abe..4198d20 100644
--- a/lib/Target/MSP430/MSP430Subtarget.cpp
+++ b/lib/Target/MSP430/MSP430Subtarget.cpp
@@ -13,6 +13,10 @@
 
 #include "MSP430Subtarget.h"
 #include "MSP430.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
 #include "MSP430GenSubtarget.inc"
 
 using namespace llvm;
diff --git a/lib/Target/MSP430/MSP430Subtarget.h b/lib/Target/MSP430/MSP430Subtarget.h
index f36428a..0a508e0 100644
--- a/lib/Target/MSP430/MSP430Subtarget.h
+++ b/lib/Target/MSP430/MSP430Subtarget.h
@@ -16,11 +16,14 @@
 
 #include "llvm/Target/TargetSubtarget.h"
 
+#define GET_SUBTARGETINFO_HEADER
+#include "MSP430GenSubtarget.inc"
+
 #include <string>
 
 namespace llvm {
 
-class MSP430Subtarget : public TargetSubtarget {
+class MSP430Subtarget : public MSP430GenSubtargetInfo {
   bool ExtendedInsts;
 public:
   /// This constructor initializes the data members to match that
diff --git a/lib/Target/Mips/MipsSubtarget.cpp b/lib/Target/Mips/MipsSubtarget.cpp
index 306ea11..9c69e04 100644
--- a/lib/Target/Mips/MipsSubtarget.cpp
+++ b/lib/Target/Mips/MipsSubtarget.cpp
@@ -13,11 +13,17 @@
 
 #include "MipsSubtarget.h"
 #include "Mips.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
 #include "MipsGenSubtarget.inc"
+
 using namespace llvm;
 
 MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU,
                              const std::string &FS, bool little) :
+  MipsGenSubtargetInfo(),
   MipsArchVersion(Mips1), MipsABI(O32), IsLittle(little), IsSingleFloat(false),
   IsFP64bit(false), IsGP64bit(false), HasVFPU(false), IsLinux(true),
   HasSEInReg(false), HasCondMov(false), HasMulDivAdd(false), HasMinMax(false),
@@ -31,6 +37,9 @@ MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU,
   // Parse features string.
   ParseSubtargetFeatures(FS, CPUName);
 
+  // Initialize scheduling itinerary for the specified CPU.
+  InstrItins = getInstrItineraryForCPU(CPUName);
+
   // Is the target system Linux ?
   if (TT.find("linux") == std::string::npos)
     IsLinux = false;
diff --git a/lib/Target/Mips/MipsSubtarget.h b/lib/Target/Mips/MipsSubtarget.h
index 8acbf5b..2b7d98f 100644
--- a/lib/Target/Mips/MipsSubtarget.h
+++ b/lib/Target/Mips/MipsSubtarget.h
@@ -18,9 +18,12 @@
 #include "llvm/MC/MCInstrItineraries.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "MipsGenSubtarget.inc"
+
 namespace llvm {
 
-class MipsSubtarget : public TargetSubtarget {
+class MipsSubtarget : public MipsGenSubtargetInfo {
 
 public:
   enum MipsABIEnum {
diff --git a/lib/Target/PTX/PTXSubtarget.cpp b/lib/Target/PTX/PTXSubtarget.cpp
index f8941b6..b3c8eb6 100644
--- a/lib/Target/PTX/PTXSubtarget.cpp
+++ b/lib/Target/PTX/PTXSubtarget.cpp
@@ -14,11 +14,17 @@
 #include "PTXSubtarget.h"
 #include "llvm/Support/ErrorHandling.h"
 
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "PTXGenSubtarget.inc"
+
 using namespace llvm;
 
 PTXSubtarget::PTXSubtarget(const std::string &TT, const std::string &CPU,
                            const std::string &FS, bool is64Bit)
-  : PTXTarget(PTX_COMPUTE_1_0),
+  : PTXGenSubtargetInfo(),
+    PTXTarget(PTX_COMPUTE_1_0),
     PTXVersion(PTX_VERSION_2_0),
     SupportsDouble(false),
     SupportsFMA(true),
diff --git a/lib/Target/PTX/PTXSubtarget.h b/lib/Target/PTX/PTXSubtarget.h
index 6d03377..b7b27d6 100644
--- a/lib/Target/PTX/PTXSubtarget.h
+++ b/lib/Target/PTX/PTXSubtarget.h
@@ -16,8 +16,11 @@
 
 #include "llvm/Target/TargetSubtarget.h"
 
+#define GET_SUBTARGETINFO_HEADER
+#include "PTXGenSubtarget.inc"
+
 namespace llvm {
-  class PTXSubtarget : public TargetSubtarget {
+  class PTXSubtarget : public PTXGenSubtargetInfo {
     public:
 
       /**
diff --git a/lib/Target/PowerPC/PPCSubtarget.cpp b/lib/Target/PowerPC/PPCSubtarget.cpp
index bcc4c21..ef8386c 100644
--- a/lib/Target/PowerPC/PPCSubtarget.cpp
+++ b/lib/Target/PowerPC/PPCSubtarget.cpp
@@ -15,8 +15,13 @@
 #include "PPC.h"
 #include "llvm/GlobalValue.h"
 #include "llvm/Target/TargetMachine.h"
-#include "PPCGenSubtarget.inc"
 #include <cstdlib>
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "PPCGenSubtarget.inc"
+
 using namespace llvm;
 
 #if defined(__APPLE__)
@@ -59,7 +64,8 @@ static const char *GetCurrentPowerPCCPU() {
 
 PPCSubtarget::PPCSubtarget(const std::string &TT, const std::string &CPU,
                            const std::string &FS, bool is64Bit)
-  : StackAlignment(16)
+  : PPCGenSubtargetInfo()
+  , StackAlignment(16)
   , DarwinDirective(PPC::DIR_NONE)
   , IsGigaProcessor(false)
   , Has64BitSupport(false)
@@ -84,6 +90,9 @@ PPCSubtarget::PPCSubtarget(const std::string &TT, const std::string &CPU,
   // Parse features string.
   ParseSubtargetFeatures(FS, CPUName);
 
+  // Initialize scheduling itinerary for the specified CPU.
+  InstrItins = getInstrItineraryForCPU(CPUName);
+
   // If we are generating code for ppc64, verify that options make sense.
   if (is64Bit) {
     Has64BitSupport = true;
diff --git a/lib/Target/PowerPC/PPCSubtarget.h b/lib/Target/PowerPC/PPCSubtarget.h
index 55c3fef..b4e5758 100644
--- a/lib/Target/PowerPC/PPCSubtarget.h
+++ b/lib/Target/PowerPC/PPCSubtarget.h
@@ -19,6 +19,9 @@
 #include "llvm/ADT/Triple.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "PPCGenSubtarget.inc"
+
 // GCC #defines PPC on Linux but we use it as our namespace name
 #undef PPC
 
@@ -42,7 +45,7 @@ namespace PPC {
 class GlobalValue;
 class TargetMachine;
   
-class PPCSubtarget : public TargetSubtarget {
+class PPCSubtarget : public PPCGenSubtargetInfo {
 protected:
   /// stackAlignment - The minimum alignment known to hold of the stack frame on
   /// entry to the function and which must be maintained by every function.
diff --git a/lib/Target/Sparc/SparcSubtarget.cpp b/lib/Target/Sparc/SparcSubtarget.cpp
index 06bfc64..3f7b23a 100644
--- a/lib/Target/Sparc/SparcSubtarget.cpp
+++ b/lib/Target/Sparc/SparcSubtarget.cpp
@@ -12,11 +12,17 @@
 //===----------------------------------------------------------------------===//
 
 #include "SparcSubtarget.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
 #include "SparcGenSubtarget.inc"
+
 using namespace llvm;
 
 SparcSubtarget::SparcSubtarget(const std::string &TT, const std::string &CPU,
                                const std::string &FS,  bool is64Bit) :
+  SparcGenSubtargetInfo(),
   IsV9(false),
   V8DeprecatedInsts(false),
   IsVIS(false),
diff --git a/lib/Target/Sparc/SparcSubtarget.h b/lib/Target/Sparc/SparcSubtarget.h
index eabf390..af35e4c 100644
--- a/lib/Target/Sparc/SparcSubtarget.h
+++ b/lib/Target/Sparc/SparcSubtarget.h
@@ -17,9 +17,12 @@
 #include "llvm/Target/TargetSubtarget.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "SparcGenSubtarget.inc"
+
 namespace llvm {
 
-class SparcSubtarget : public TargetSubtarget {
+class SparcSubtarget : public SparcGenSubtargetInfo {
   bool IsV9;
   bool V8DeprecatedInsts;
   bool IsVIS;
diff --git a/lib/Target/SystemZ/SystemZSubtarget.cpp b/lib/Target/SystemZ/SystemZSubtarget.cpp
index 95521b2..33c9906 100644
--- a/lib/Target/SystemZ/SystemZSubtarget.cpp
+++ b/lib/Target/SystemZ/SystemZSubtarget.cpp
@@ -13,16 +13,20 @@
 
 #include "SystemZSubtarget.h"
 #include "SystemZ.h"
-#include "SystemZGenSubtarget.inc"
 #include "llvm/GlobalValue.h"
 #include "llvm/Target/TargetMachine.h"
 
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "SystemZGenSubtarget.inc"
+
 using namespace llvm;
 
 SystemZSubtarget::SystemZSubtarget(const std::string &TT, 
                                    const std::string &CPU,
                                    const std::string &FS):
-  HasZ10Insts(false) {
+  SystemZGenSubtargetInfo(), HasZ10Insts(false) {
   std::string CPUName = CPU;
   if (CPUName.empty())
     CPUName = "z9";
diff --git a/lib/Target/SystemZ/SystemZSubtarget.h b/lib/Target/SystemZ/SystemZSubtarget.h
index 453471c..a08f2da 100644
--- a/lib/Target/SystemZ/SystemZSubtarget.h
+++ b/lib/Target/SystemZ/SystemZSubtarget.h
@@ -15,14 +15,16 @@
 #define LLVM_TARGET_SystemZ_SUBTARGET_H
 
 #include "llvm/Target/TargetSubtarget.h"
-
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "SystemZGenSubtarget.inc"
+
 namespace llvm {
 class GlobalValue;
 class TargetMachine;
 
-class SystemZSubtarget : public TargetSubtarget {
+class SystemZSubtarget : public SystemZGenSubtargetInfo {
   bool HasZ10Insts;
 public:
   /// This constructor initializes the data members to match that
diff --git a/lib/Target/X86/X86Subtarget.cpp b/lib/Target/X86/X86Subtarget.cpp
index d7f630c..5c653f6 100644
--- a/lib/Target/X86/X86Subtarget.cpp
+++ b/lib/Target/X86/X86Subtarget.cpp
@@ -14,13 +14,18 @@
 #define DEBUG_TYPE "subtarget"
 #include "X86Subtarget.h"
 #include "X86InstrInfo.h"
-#include "X86GenSubtarget.inc"
 #include "llvm/GlobalValue.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/ADT/SmallVector.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "X86GenSubtarget.inc"
+
 using namespace llvm;
 
 #if defined(_MSC_VER)
@@ -287,7 +292,8 @@ void X86Subtarget::AutoDetectSubtargetFeatures() {
 X86Subtarget::X86Subtarget(const std::string &TT, const std::string &CPU,
                            const std::string &FS, 
                            bool is64Bit, unsigned StackAlignOverride)
-  : PICStyle(PICStyles::None)
+  : X86GenSubtargetInfo()
+  , PICStyle(PICStyles::None)
   , X86SSELevel(NoMMXSSE)
   , X863DNowLevel(NoThreeDNow)
   , HasCMov(false)
diff --git a/lib/Target/X86/X86Subtarget.h b/lib/Target/X86/X86Subtarget.h
index 80a4103..cafc082 100644
--- a/lib/Target/X86/X86Subtarget.h
+++ b/lib/Target/X86/X86Subtarget.h
@@ -19,6 +19,9 @@
 #include "llvm/CallingConv.h"
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "X86GenSubtarget.inc"
+
 namespace llvm {
 class GlobalValue;
 class TargetMachine;
@@ -35,7 +38,7 @@ enum Style {
 };
 }
 
-class X86Subtarget : public TargetSubtarget {
+class X86Subtarget : public X86GenSubtargetInfo {
 protected:
   enum X86SSEEnum {
     NoMMXSSE, MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42
diff --git a/lib/Target/XCore/XCoreSubtarget.cpp b/lib/Target/XCore/XCoreSubtarget.cpp
index 0447d2e..ef13520 100644
--- a/lib/Target/XCore/XCoreSubtarget.cpp
+++ b/lib/Target/XCore/XCoreSubtarget.cpp
@@ -13,9 +13,16 @@
 
 #include "XCoreSubtarget.h"
 #include "XCore.h"
+
+#define GET_SUBTARGETINFO_CTOR
+#define GET_SUBTARGETINFO_MC_DESC
+#define GET_SUBTARGETINFO_TARGET_DESC
+#include "XCoreGenSubtarget.inc"
+
 using namespace llvm;
 
 XCoreSubtarget::XCoreSubtarget(const std::string &TT,
                                const std::string &CPU, const std::string &FS)
+  : XCoreGenSubtargetInfo()
 {
 }
diff --git a/lib/Target/XCore/XCoreSubtarget.h b/lib/Target/XCore/XCoreSubtarget.h
index ee40d36..182e5c4 100644
--- a/lib/Target/XCore/XCoreSubtarget.h
+++ b/lib/Target/XCore/XCoreSubtarget.h
@@ -16,12 +16,14 @@
 
 #include "llvm/Target/TargetSubtarget.h"
 #include "llvm/Target/TargetMachine.h"
-
 #include <string>
 
+#define GET_SUBTARGETINFO_HEADER
+#include "XCoreGenSubtarget.inc"
+
 namespace llvm {
 
-class XCoreSubtarget : public TargetSubtarget {
+class XCoreSubtarget : public XCoreGenSubtargetInfo {
 
 public:
   /// This constructor initializes the data members to match that
diff --git a/utils/TableGen/InstrInfoEmitter.cpp b/utils/TableGen/InstrInfoEmitter.cpp
index 5e2fdf0..18d4db0 100644
--- a/utils/TableGen/InstrInfoEmitter.cpp
+++ b/utils/TableGen/InstrInfoEmitter.cpp
@@ -223,7 +223,7 @@ void InstrInfoEmitter::run(raw_ostream &OS) {
   OS << "#undef GET_INSTRINFO_HEADER\n";
 
   std::string ClassName = TargetName + "GenInstrInfo";
-  OS << "namespace llvm {\n\n";
+  OS << "namespace llvm {\n";
   OS << "struct " << ClassName << " : public TargetInstrInfoImpl {\n"
      << "  explicit " << ClassName << "(int SO = -1, int DO = -1);\n"
      << "};\n";
@@ -234,7 +234,7 @@ void InstrInfoEmitter::run(raw_ostream &OS) {
   OS << "\n#ifdef GET_INSTRINFO_CTOR\n";
   OS << "#undef GET_INSTRINFO_CTOR\n";
 
-  OS << "namespace llvm {\n\n";
+  OS << "namespace llvm {\n";
   OS << ClassName << "::" << ClassName << "(int SO, int DO)\n"
      << "  : TargetInstrInfoImpl(SO, DO) {\n"
      << "  InitMCInstrInfo(" << TargetName << "Insts, "
diff --git a/utils/TableGen/SubtargetEmitter.cpp b/utils/TableGen/SubtargetEmitter.cpp
index c823cb1..a55836f 100644
--- a/utils/TableGen/SubtargetEmitter.cpp
+++ b/utils/TableGen/SubtargetEmitter.cpp
@@ -29,16 +29,20 @@ void SubtargetEmitter::Enumeration(raw_ostream &OS,
   std::vector<Record*> DefList = Records.getAllDerivedDefinitions(ClassName);
   std::sort(DefList.begin(), DefList.end(), LessRecord());
 
-  // Open enumeration
-  OS << "enum {\n";
-
-  // For each record
   unsigned N = DefList.size();
+  if (N == 0)
+    return;
   if (N > 64) {
     errs() << "Too many (> 64) subtarget features!\n";
     exit(1);
   }
 
+  OS << "namespace " << Target << " {\n";
+
+  // Open enumeration
+  OS << "enum {\n";
+
+  // For each record
   for (unsigned i = 0; i < N;) {
     // Next record
     Record *Def = DefList[i];
@@ -57,23 +61,31 @@ void SubtargetEmitter::Enumeration(raw_ostream &OS,
 
   // Close enumeration
   OS << "};\n";
+
+  OS << "}\n";
 }
 
 //
 // FeatureKeyValues - Emit data of all the subtarget features.  Used by the
 // command line.
 //
-void SubtargetEmitter::FeatureKeyValues(raw_ostream &OS) {
+unsigned SubtargetEmitter::FeatureKeyValues(raw_ostream &OS) {
   // Gather and sort all the features
   std::vector<Record*> FeatureList =
                            Records.getAllDerivedDefinitions("SubtargetFeature");
+
+  if (FeatureList.empty())
+    return 0;
+
   std::sort(FeatureList.begin(), FeatureList.end(), LessRecordFieldName());
 
   // Begin feature table
   OS << "// Sorted (by key) array of values for CPU features.\n"
-     << "static const llvm::SubtargetFeatureKV FeatureKV[] = {\n";
+     << "static const llvm::SubtargetFeatureKV "
+     << Target << "FeatureKV[] = {\n";
 
   // For each feature
+  unsigned NumFeatures = 0;
   for (unsigned i = 0, N = FeatureList.size(); i < N; ++i) {
     // Next feature
     Record *Feature = FeatureList[i];
@@ -88,7 +100,7 @@ void SubtargetEmitter::FeatureKeyValues(raw_ostream &OS) {
     OS << "  { "
        << "\"" << CommandLineName << "\", "
        << "\"" << Desc << "\", "
-       << Name << ", ";
+       << Target << "::" << Name << ", ";
 
     const std::vector<Record*> &ImpliesList =
       Feature->getValueAsListOfDefs("Implies");
@@ -97,12 +109,13 @@ void SubtargetEmitter::FeatureKeyValues(raw_ostream &OS) {
       OS << "0ULL";
     } else {
       for (unsigned j = 0, M = ImpliesList.size(); j < M;) {
-        OS << ImpliesList[j]->getName();
+        OS << Target << "::" << ImpliesList[j]->getName();
         if (++j < M) OS << " | ";
       }
     }
 
     OS << " }";
+    ++NumFeatures;
 
     // Depending on 'if more in the list' emit comma
     if ((i + 1) < N) OS << ",";
@@ -113,17 +126,14 @@ void SubtargetEmitter::FeatureKeyValues(raw_ostream &OS) {
   // End feature table
   OS << "};\n";
 
-  // Emit size of table
-  OS<<"\nenum {\n";
-  OS<<"  FeatureKVSize = sizeof(FeatureKV)/sizeof(llvm::SubtargetFeatureKV)\n";
-  OS<<"};\n";
+  return NumFeatures;
 }
 
 //
 // CPUKeyValues - Emit data of all the subtarget processors.  Used by command
 // line.
 //
-void SubtargetEmitter::CPUKeyValues(raw_ostream &OS) {
+unsigned SubtargetEmitter::CPUKeyValues(raw_ostream &OS) {
   // Gather and sort processor information
   std::vector<Record*> ProcessorList =
                           Records.getAllDerivedDefinitions("Processor");
@@ -131,7 +141,8 @@ void SubtargetEmitter::CPUKeyValues(raw_ostream &OS) {
 
   // Begin processor table
   OS << "// Sorted (by key) array of values for CPU subtype.\n"
-     << "static const llvm::SubtargetFeatureKV SubTypeKV[] = {\n";
+     << "static const llvm::SubtargetFeatureKV "
+     << Target << "SubTypeKV[] = {\n";
 
   // For each processor
   for (unsigned i = 0, N = ProcessorList.size(); i < N;) {
@@ -151,7 +162,7 @@ void SubtargetEmitter::CPUKeyValues(raw_ostream &OS) {
       OS << "0ULL";
     } else {
       for (unsigned j = 0, M = FeatureList.size(); j < M;) {
-        OS << FeatureList[j]->getName();
+        OS << Target << "::" << FeatureList[j]->getName();
         if (++j < M) OS << " | ";
       }
     }
@@ -168,10 +179,7 @@ void SubtargetEmitter::CPUKeyValues(raw_ostream &OS) {
   // End processor table
   OS << "};\n";
 
-  // Emit size of table
-  OS<<"\nenum {\n";
-  OS<<"  SubTypeKVSize = sizeof(SubTypeKV)/sizeof(llvm::SubtargetFeatureKV)\n";
-  OS<<"};\n";
+  return ProcessorList.size();
 }
 
 //
@@ -192,11 +200,6 @@ CollectAllItinClasses(raw_ostream &OS,
     ItinClassesMap[ItinClass->getName()] = i;
   }
 
-  // Emit size of table
-  OS<<"\nenum {\n";
-  OS<<"  ItinClassesSize = " << N << "\n";
-  OS<<"};\n";
-
   // Return itinerary class count
   return N;
 }
@@ -336,15 +339,18 @@ void SubtargetEmitter::EmitStageAndOperandCycleData(raw_ostream &OS,
   }
 
   // Begin stages table
-  std::string StageTable = "\nstatic const llvm::InstrStage Stages[] = {\n";
+  std::string StageTable = "\nstatic const llvm::InstrStage " + Target +
+    "Stages[] = {\n";
   StageTable += "  { 0, 0, 0, llvm::InstrStage::Required }, // No itinerary\n";
 
   // Begin operand cycle table
-  std::string OperandCycleTable = "static const unsigned OperandCycles[] = {\n";
+  std::string OperandCycleTable = "static const unsigned " + Target +
+    "OperandCycles[] = {\n";
   OperandCycleTable += "  0, // No itinerary\n";
 
   // Begin pipeline bypass table
-  std::string BypassTable = "static const unsigned ForwardingPathes[] = {\n";
+  std::string BypassTable = "static const unsigned " + Target +
+    "ForwardingPathes[] = {\n";
   BypassTable += "  0, // No itinerary\n";
 
   unsigned StageCount = 1, OperandCycleCount = 1;
@@ -457,12 +463,6 @@ void SubtargetEmitter::EmitStageAndOperandCycleData(raw_ostream &OS,
   OS << StageTable;
   OS << OperandCycleTable;
   OS << BypassTable;
-
-  // Emit size of tables
-  OS<<"\nenum {\n";
-  OS<<"  StagesSize = sizeof(Stages)/sizeof(llvm::InstrStage),\n";
-  OS<<"  OperandCyclesSize = sizeof(OperandCycles)/sizeof(unsigned)\n";
-  OS<<"};\n";
 }
 
 //
@@ -533,7 +533,8 @@ void SubtargetEmitter::EmitProcessorLookup(raw_ostream &OS) {
   // Begin processor table
   OS << "\n";
   OS << "// Sorted (by key) array of itineraries for CPU subtype.\n"
-     << "static const llvm::SubtargetInfoKV ProcItinKV[] = {\n";
+     << "static const llvm::SubtargetInfoKV "
+     << Target << "ProcItinKV[] = {\n";
 
   // For each processor
   for (unsigned i = 0, N = ProcessorList.size(); i < N;) {
@@ -559,12 +560,6 @@ void SubtargetEmitter::EmitProcessorLookup(raw_ostream &OS) {
 
   // End processor table
   OS << "};\n";
-
-  // Emit size of table
-  OS<<"\nenum {\n";
-  OS<<"  ProcItinKVSize = sizeof(ProcItinKV)/"
-                            "sizeof(llvm::SubtargetInfoKV)\n";
-  OS<<"};\n";
 }
 
 //
@@ -599,7 +594,9 @@ void SubtargetEmitter::EmitData(raw_ostream &OS) {
 // ParseFeaturesFunction - Produces a subtarget specific function for parsing
 // the subtarget features string.
 //
-void SubtargetEmitter::ParseFeaturesFunction(raw_ostream &OS) {
+void SubtargetEmitter::ParseFeaturesFunction(raw_ostream &OS,
+                                             unsigned NumFeatures,
+                                             unsigned NumProcs) {
   std::vector<Record*> Features =
                        Records.getAllDerivedDefinitions("SubtargetFeature");
   std::sort(Features.begin(), Features.end(), LessRecord());
@@ -611,11 +608,18 @@ void SubtargetEmitter::ParseFeaturesFunction(raw_ostream &OS) {
   OS << "Subtarget::ParseSubtargetFeatures(const std::string &FS,\n"
      << "                                  const std::string &CPU) {\n"
      << "  DEBUG(dbgs() << \"\\nFeatures:\" << FS);\n"
-     << "  DEBUG(dbgs() << \"\\nCPU:\" << CPU);\n"
-     << "  SubtargetFeatures Features(FS);\n"
+     << "  DEBUG(dbgs() << \"\\nCPU:\" << CPU);\n";
+
+  if (Features.empty()) {
+    OS << "}\n";
+    return;
+  }
+
+  OS << "  SubtargetFeatures Features(FS);\n"
      << "  uint64_t Bits =  Features.getFeatureBits(CPU, "
-     << "SubTypeKV, SubTypeKVSize,\n"
-     << "                                    FeatureKV, FeatureKVSize);\n";
+     << Target << "SubTypeKV, " << NumProcs << ",\n"
+     << "                                    " << Target << "FeatureKV, "
+     << NumFeatures << ");\n";
 
   for (unsigned i = 0; i < Features.size(); i++) {
     // Next record
@@ -625,20 +629,12 @@ void SubtargetEmitter::ParseFeaturesFunction(raw_ostream &OS) {
     const std::string &Attribute = R->getValueAsString("Attribute");
 
     if (Value=="true" || Value=="false")
-      OS << "  if ((Bits & " << Instance << ") != 0) "
+      OS << "  if ((Bits & " << Target << "::" << Instance << ") != 0) "
          << Attribute << " = " << Value << ";\n";
     else
-      OS << "  if ((Bits & " << Instance << ") != 0 && " << Attribute <<
-            " < " << Value << ") " << Attribute << " = " << Value << ";\n";
-  }
-
-  if (HasItineraries) {
-    OS << "\n"
-       << "  InstrItinerary *Itinerary = (InstrItinerary *)"
-       <<              "Features.getItinerary(CPU, "
-       << "ProcItinKV, ProcItinKVSize);\n"
-       << "  InstrItins = InstrItineraryData(Stages, OperandCycles, "
-       << "ForwardingPathes, Itinerary);\n";
+      OS << "  if ((Bits & " << Target << "::" << Instance << ") != 0 && "
+         << Attribute << " < " << Value << ") "
+         << Attribute << " = " << Value << ";\n";
   }
 
   OS << "}\n";
@@ -652,22 +648,90 @@ void SubtargetEmitter::run(raw_ostream &OS) {
 
   EmitSourceFileHeader("Subtarget Enumeration Source Fragment", OS);
 
-  OS << "#include \"llvm/Support/Debug.h\"\n";
-  OS << "#include \"llvm/Support/raw_ostream.h\"\n";
-  OS << "#include \"llvm/MC/SubtargetFeature.h\"\n";
-  OS << "#include \"llvm/MC/MCInstrItineraries.h\"\n\n";
+  OS << "\n#ifdef GET_SUBTARGETINFO_MC_DESC\n";
+  OS << "#undef GET_SUBTARGETINFO_MC_DESC\n";
 
-//  Enumeration(OS, "FuncUnit", true);
-//  OS<<"\n";
-//  Enumeration(OS, "InstrItinClass", false);
-//  OS<<"\n";
+  OS << "namespace llvm {\n";
   Enumeration(OS, "SubtargetFeature", true);
   OS<<"\n";
-  FeatureKeyValues(OS);
+  unsigned NumFeatures = FeatureKeyValues(OS);
   OS<<"\n";
-  CPUKeyValues(OS);
+  unsigned NumProcs = CPUKeyValues(OS);
   OS<<"\n";
   EmitData(OS);
   OS<<"\n";
-  ParseFeaturesFunction(OS);
+
+  // MCInstrInfo initialization routine.
+  OS << "static inline void Init" << Target
+     << "MCSubtargetInfo(MCSubtargetInfo *II) {\n";
+  OS << "  II->InitMCSubtargetInfo(";
+  if (NumFeatures)
+    OS << Target << "FeatureKV, ";
+  else
+    OS << "0, ";
+  if (NumProcs)
+    OS << Target << "SubTypeKV, ";
+  else
+    OS << "0, ";
+  if (HasItineraries) {
+    OS << Target << "ProcItinKV, "
+       << Target << "Stages, "
+       << Target << "OperandCycles, "
+       << Target << "ForwardingPathes, ";
+  } else
+    OS << "0, 0, 0, 0, ";
+  OS << NumFeatures << ", " << NumProcs << ");\n}\n\n";
+
+  OS << "} // End llvm namespace \n";
+
+  OS << "#endif // GET_SUBTARGETINFO_MC_DESC\n\n";
+
+  OS << "\n#ifdef GET_SUBTARGETINFO_TARGET_DESC\n";
+  OS << "#undef GET_SUBTARGETINFO_TARGET_DESC\n";
+
+  OS << "#include \"llvm/Support/Debug.h\"\n";
+  OS << "#include \"llvm/Support/raw_ostream.h\"\n";
+  ParseFeaturesFunction(OS, NumFeatures, NumProcs);
+
+  OS << "#endif // GET_SUBTARGETINFO_TARGET_DESC\n\n";
+
+  // Create a TargetSubtarget subclass to hide the MC layer initialization.
+  OS << "\n#ifdef GET_SUBTARGETINFO_HEADER\n";
+  OS << "#undef GET_SUBTARGETINFO_HEADER\n";
+
+  std::string ClassName = Target + "GenSubtargetInfo";
+  OS << "namespace llvm {\n";
+  OS << "struct " << ClassName << " : public TargetSubtarget {\n"
+     << "  explicit " << ClassName << "();\n"
+     << "};\n";
+  OS << "} // End llvm namespace \n";
+
+  OS << "#endif // GET_SUBTARGETINFO_HEADER\n\n";
+
+  OS << "\n#ifdef GET_SUBTARGETINFO_CTOR\n";
+  OS << "#undef GET_SUBTARGETINFO_CTOR\n";
+
+  OS << "namespace llvm {\n";
+  OS << ClassName << "::" << ClassName << "()\n"
+     << "  : TargetSubtarget() {\n"
+     << "  InitMCSubtargetInfo(";
+  if (NumFeatures)
+    OS << Target << "FeatureKV, ";
+  else
+    OS << "0, ";
+  if (NumProcs)
+    OS << Target << "SubTypeKV, ";
+  else
+    OS << "0, ";
+  if (HasItineraries) {
+    OS << Target << "ProcItinKV, "
+       << Target << "Stages, "
+       << Target << "OperandCycles, "
+       << Target << "ForwardingPathes, ";
+  } else
+    OS << "0, 0, 0, 0, ";
+  OS << NumFeatures << ", " << NumProcs << ");\n}\n\n";
+  OS << "} // End llvm namespace \n";
+
+  OS << "#endif // GET_SUBTARGETINFO_CTOR\n\n";
 }
diff --git a/utils/TableGen/SubtargetEmitter.h b/utils/TableGen/SubtargetEmitter.h
index cf793c8..b239f3d 100644
--- a/utils/TableGen/SubtargetEmitter.h
+++ b/utils/TableGen/SubtargetEmitter.h
@@ -30,8 +30,8 @@ class SubtargetEmitter : public TableGenBackend {
   bool HasItineraries;
 
   void Enumeration(raw_ostream &OS, const char *ClassName, bool isBits);
-  void FeatureKeyValues(raw_ostream &OS);
-  void CPUKeyValues(raw_ostream &OS);
+  unsigned FeatureKeyValues(raw_ostream &OS);
+  unsigned CPUKeyValues(raw_ostream &OS);
   unsigned CollectAllItinClasses(raw_ostream &OS,
                                  std::map<std::string,unsigned> &ItinClassesMap,
                                  std::vector<Record*> &ItinClassList);
@@ -52,7 +52,8 @@ class SubtargetEmitter : public TableGenBackend {
                          std::vector<std::vector<InstrItinerary> > &ProcList);
   void EmitProcessorLookup(raw_ostream &OS);
   void EmitData(raw_ostream &OS);
-  void ParseFeaturesFunction(raw_ostream &OS);
+  void ParseFeaturesFunction(raw_ostream &OS, unsigned NumFeatures,
+                             unsigned NumProcs);
 
 public:
   SubtargetEmitter(RecordKeeper &R) : Records(R), HasItineraries(false) {}