Add an instruction deprecation feature to TableGen.

The 'Deprecated' class allows you to specify a SubtargetFeature that the
instruction is deprecated on.

The 'ComplexDeprecationPredicate' class allows you to define a custom
predicate that is called to check for deprecation.
For example:
  ComplexDeprecationPredicate<"MCR">

would mean you would have to define the following function:
  bool getMCRDeprecationInfo(MCInst &MI, MCSubtargetInfo &STI,
                             std::string &Info)

Which returns 'false' for not deprecated, and 'true' for deprecated
and store the warning message in 'Info'.

The MCTargetAsmParser constructor was chaned to take an extra argument of
the MCInstrInfo class, so out-of-tree targets will need to be changed.

llvm-svn: 190598

include/llvm/CodeGen/AsmPrinter.h

@@ -41,6 +41,7 @@ namespace llvm {
   class MCAsmInfo;
   class MCCFIInstruction;
   class MCContext;
+  class MCInstrInfo;
   class MCSection;
   class MCStreamer;
   class MCSymbol;
@@ -64,6 +65,7 @@ namespace llvm {
     ///
     const MCAsmInfo *MAI;
 
+    const MCInstrInfo *MII;
     /// OutContext - This is the context for the output file that we are
     /// streaming.  This owns all of the global MC-related objects for the
     /// generated translation unit.

include/llvm/MC/MCInstrDesc.h

@@ -17,6 +17,7 @@
 
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCSubtargetInfo.h"
 #include "llvm/Support/DataTypes.h"
 
 namespace llvm {
@@ -145,6 +146,10 @@ public:
   const uint16_t *ImplicitUses;  // Registers implicitly read by this instr
   const uint16_t *ImplicitDefs;  // Registers implicitly defined by this instr
   const MCOperandInfo *OpInfo;   // 'NumOperands' entries about operands
+  uint64_t DeprecatedFeatureMask;// Feature bits that this is deprecated on, if any
+  // A complex method to determine is a certain is deprecated or not, and return
+  // the reason for deprecation.
+  bool (*ComplexDeprecationInfo)(MCInst &, MCSubtargetInfo &, std::string &);
 
   /// \brief Returns the value of the specific constraint if
   /// it is set. Returns -1 if it is not set.
@@ -158,6 +163,20 @@ public:
     return -1;
   }
 
+  /// \brief Returns true if a certain instruction is deprecated and if so
+  /// returns the reason in \p Info.
+  bool getDeprecatedInfo(MCInst &MI, MCSubtargetInfo &STI,
+                         std::string &Info) const {
+    if (ComplexDeprecationInfo)
+      return ComplexDeprecationInfo(MI, STI, Info);
+    if (DeprecatedFeatureMask != 0) {
+      // FIXME: it would be nice to include the subtarget feature here.
+      Info = "deprecated";
+      return true;
+    }
+    return false;
+  }
+
   /// \brief Return the opcode number for this descriptor.
   unsigned getOpcode() const {
     return Opcode;

include/llvm/Support/TargetRegistry.h

@@ -108,7 +108,8 @@ namespace llvm {
                                                 StringRef TT,
                                                 StringRef CPU);
     typedef MCTargetAsmParser *(*MCAsmParserCtorTy)(MCSubtargetInfo &STI,
-                                                    MCAsmParser &P);
+                                                    MCAsmParser &P,
+                                                    const MCInstrInfo &MII);
     typedef MCDisassembler *(*MCDisassemblerCtorTy)(const Target &T,
                                                     const MCSubtargetInfo &STI);
     typedef MCInstPrinter *(*MCInstPrinterCtorTy)(const Target &T,
@@ -386,10 +387,11 @@ namespace llvm {
     /// \param Parser The target independent parser implementation to use for
     /// parsing and lexing.
     MCTargetAsmParser *createMCAsmParser(MCSubtargetInfo &STI,
-                                         MCAsmParser &Parser) const {
+                                         MCAsmParser &Parser,
+                                         const MCInstrInfo &MII) const {
       if (!MCAsmParserCtorFn)
         return 0;
-      return MCAsmParserCtorFn(STI, Parser);
+      return MCAsmParserCtorFn(STI, Parser, MII);
     }
 
     /// createAsmPrinter - Create a target specific assembly printer pass.  This
@@ -1142,8 +1144,9 @@ namespace llvm {
     }
 
   private:
-    static MCTargetAsmParser *Allocator(MCSubtargetInfo &STI, MCAsmParser &P) {
+    static MCTargetAsmParser *Allocator(MCSubtargetInfo &STI, MCAsmParser &P,
-      return new MCAsmParserImpl(STI, P);
+                                        const MCInstrInfo &MII) {
+      return new MCAsmParserImpl(STI, P, MII);
     }
   };
 

include/llvm/Target/Target.td

@@ -1010,6 +1010,17 @@ class SubtargetFeature<string n, string a,  string v, string d,
   list<SubtargetFeature> Implies = i;
 }
 
+/// Specifies a Subtarget feature that this instruction is deprecated on.
+class Deprecated<SubtargetFeature dep> {
+  SubtargetFeature DeprecatedFeatureMask = dep;
+}
+
+/// A custom predicate used to determine if an instruction is
+/// deprecated or not.
+class ComplexDeprecationPredicate<string dep> {
+  string ComplexDeprecationPredicate = dep;
+}
+
 //===----------------------------------------------------------------------===//
 // Processor chip sets - These values represent each of the chip sets supported
 // by the scheduler.  Each Processor definition requires corresponding

lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -94,7 +94,7 @@ static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
 
 AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
   : MachineFunctionPass(ID),
-    TM(tm), MAI(tm.getMCAsmInfo()),
+    TM(tm), MAI(tm.getMCAsmInfo()), MII(tm.getInstrInfo()),
     OutContext(Streamer.getContext()),
     OutStreamer(Streamer),
     LastMI(0), LastFn(0), Counter(~0U), SetCounter(0) {

lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp

@@ -123,7 +123,7 @@ void AsmPrinter::EmitInlineAsm(StringRef Str, const MDNode *LocMDNode,
                                              TM.getTargetCPU(),
                                              TM.getTargetFeatureString()));
   OwningPtr<MCTargetAsmParser>
-    TAP(TM.getTarget().createMCAsmParser(*STI, *Parser));
+    TAP(TM.getTarget().createMCAsmParser(*STI, *Parser, *MII));
   if (!TAP)
     report_fatal_error("Inline asm not supported by this streamer because"
                        " we don't have an asm parser for this target\n");

lib/Target/AArch64/AsmParser/AArch64AsmParser.cpp

@@ -54,8 +54,9 @@ public:
 #include "AArch64GenAsmMatcher.inc"
   };
 
-  AArch64AsmParser(MCSubtargetInfo &_STI, MCAsmParser &_Parser)
+  AArch64AsmParser(MCSubtargetInfo &_STI, MCAsmParser &_Parser,
-    : MCTargetAsmParser(), STI(_STI), Parser(_Parser) {
+                   const MCInstrInfo &MII)
+      : MCTargetAsmParser(), STI(_STI), Parser(_Parser) {
     MCAsmParserExtension::Initialize(_Parser);
 
     // Initialize the set of available features.

lib/Target/ARM/ARMInstrInfo.td

@@ -1840,7 +1840,7 @@ defm PLDW : APreLoad<0, 1, "pldw">, Requires<[IsARM,HasV7,HasMP]>;
 defm PLI  : APreLoad<1, 0, "pli">,  Requires<[IsARM,HasV7]>;
 
 def SETEND : AXI<(outs), (ins setend_op:$end), MiscFrm, NoItinerary,
-                 "setend\t$end", []>, Requires<[IsARM]> {
+                 "setend\t$end", []>, Requires<[IsARM]>, Deprecated<HasV8Ops> {
   bits<1> end;
   let Inst{31-10} = 0b1111000100000001000000;
   let Inst{9} = end;
@@ -4772,7 +4772,8 @@ def MCR : MovRCopro<"mcr", 0 /* from ARM core register to coprocessor */,
                     (ins p_imm:$cop, imm0_7:$opc1, GPR:$Rt, c_imm:$CRn,
                          c_imm:$CRm, imm0_7:$opc2),
                     [(int_arm_mcr imm:$cop, imm:$opc1, GPR:$Rt, imm:$CRn,
-                                  imm:$CRm, imm:$opc2)]>;
+                                  imm:$CRm, imm:$opc2)]>,
+                    ComplexDeprecationPredicate<"MCR">;
 def : ARMInstAlias<"mcr${p} $cop, $opc1, $Rt, $CRn, $CRm",
                    (MCR p_imm:$cop, imm0_7:$opc1, GPR:$Rt, c_imm:$CRn,
                         c_imm:$CRm, 0, pred:$p)>;

lib/Target/ARM/AsmParser/ARMAsmParser.cpp

@@ -24,6 +24,7 @@
 #include "llvm/MC/MCExpr.h"
 #include "llvm/MC/MCInst.h"
 #include "llvm/MC/MCInstrDesc.h"
+#include "llvm/MC/MCInstrInfo.h"
 #include "llvm/MC/MCParser/MCAsmLexer.h"
 #include "llvm/MC/MCParser/MCAsmParser.h"
 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
@@ -47,6 +48,7 @@ enum VectorLaneTy { NoLanes, AllLanes, IndexedLane };
 class ARMAsmParser : public MCTargetAsmParser {
   MCSubtargetInfo &STI;
   MCAsmParser &Parser;
+  const MCInstrInfo &MII;
   const MCRegisterInfo *MRI;
 
   // Unwind directives state
@@ -232,8 +234,6 @@ class ARMAsmParser : public MCTargetAsmParser {
                               SmallVectorImpl<MCParsedAsmOperand*> &Operands);
   bool shouldOmitPredicateOperand(StringRef Mnemonic,
                               SmallVectorImpl<MCParsedAsmOperand*> &Operands);
-  bool isDeprecated(MCInst &Inst, StringRef &Info);
-
 public:
   enum ARMMatchResultTy {
     Match_RequiresITBlock = FIRST_TARGET_MATCH_RESULT_TY,
@@ -245,8 +245,9 @@ public:
 
   };
 
-  ARMAsmParser(MCSubtargetInfo &_STI, MCAsmParser &_Parser)
+  ARMAsmParser(MCSubtargetInfo &_STI, MCAsmParser &_Parser,
-    : MCTargetAsmParser(), STI(_STI), Parser(_Parser), FPReg(-1) {
+               const MCInstrInfo &MII)
+      : MCTargetAsmParser(), STI(_STI), Parser(_Parser), MII(MII), FPReg(-1) {
     MCAsmParserExtension::Initialize(_Parser);
 
     // Cache the MCRegisterInfo.
@@ -4972,14 +4973,6 @@ bool ARMAsmParser::shouldOmitPredicateOperand(
   return false;
 }
 
-bool ARMAsmParser::isDeprecated(MCInst &Inst, StringRef &Info) {
-  if (hasV8Ops() && Inst.getOpcode() == ARM::SETEND) {
-    Info = "armv8";
-    return true;
-  }
-  return false;
-}
-
 static bool isDataTypeToken(StringRef Tok) {
   return Tok == ".8" || Tok == ".16" || Tok == ".32" || Tok == ".64" ||
     Tok == ".i8" || Tok == ".i16" || Tok == ".i32" || Tok == ".i64" ||
@@ -5296,16 +5289,6 @@ static bool listContainsReg(MCInst &Inst, unsigned OpNo, unsigned Reg) {
   return false;
 }
 
-// FIXME: We would really prefer to have MCInstrInfo (the wrapper around
-// the ARMInsts array) instead. Getting that here requires awkward
-// API changes, though. Better way?
-namespace llvm {
-extern const MCInstrDesc ARMInsts[];
-}
-static const MCInstrDesc &getInstDesc(unsigned Opcode) {
-  return ARMInsts[Opcode];
-}
-
 // Return true if instruction has the interesting property of being
 // allowed in IT blocks, but not being predicable.
 static bool instIsBreakpoint(const MCInst &Inst) {
@@ -5320,7 +5303,7 @@ static bool instIsBreakpoint(const MCInst &Inst) {
 bool ARMAsmParser::
 validateInstruction(MCInst &Inst,
                     const SmallVectorImpl<MCParsedAsmOperand*> &Operands) {
-  const MCInstrDesc &MCID = getInstDesc(Inst.getOpcode());
+  const MCInstrDesc &MCID = MII.get(Inst.getOpcode());
   SMLoc Loc = Operands[0]->getStartLoc();
 
   // Check the IT block state first.
@@ -5513,10 +5496,6 @@ validateInstruction(MCInst &Inst,
   }
   }
 
-  StringRef DepInfo;
-  if (isDeprecated(Inst, DepInfo))
-    Warning(Loc, "deprecated on " + DepInfo);
-
   return false;
 }
 
@@ -7553,7 +7532,7 @@ unsigned ARMAsmParser::checkTargetMatchPredicate(MCInst &Inst) {
   // 16-bit thumb arithmetic instructions either require or preclude the 'S'
   // suffix depending on whether they're in an IT block or not.
   unsigned Opc = Inst.getOpcode();
-  const MCInstrDesc &MCID = getInstDesc(Opc);
+  const MCInstrDesc &MCID = MII.get(Opc);
   if (MCID.TSFlags & ARMII::ThumbArithFlagSetting) {
     assert(MCID.hasOptionalDef() &&
            "optionally flag setting instruction missing optional def operand");

lib/Target/ARM/MCTargetDesc/ARMMCTargetDesc.cpp

@@ -26,16 +26,32 @@
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/TargetRegistry.h"
 
+using namespace llvm;
+
 #define GET_REGINFO_MC_DESC
 #include "ARMGenRegisterInfo.inc"
 
+static bool getMCRDeprecationInfo(MCInst &MI, MCSubtargetInfo &STI,
+                                  std::string &Info) {
+  // Checks for the deprecated CP15ISB encoding:
+  // mcr pX, #0, rX, c7, c5, #4
+  if (STI.getFeatureBits() & llvm::ARM::HasV8Ops &&
+      (MI.getOperand(1).isImm() && MI.getOperand(1).getImm() == 0) &&
+      (MI.getOperand(3).isImm() && MI.getOperand(3).getImm() == 7) &&
+      (MI.getOperand(4).isImm() && MI.getOperand(4).getImm() == 5) &&
+      (MI.getOperand(5).isImm() && MI.getOperand(5).getImm() == 4)) {
+    Info = "deprecated on armv8";
+    return true;
+  }
+  return false;
+}
+
 #define GET_INSTRINFO_MC_DESC
 #include "ARMGenInstrInfo.inc"
 
 #define GET_SUBTARGETINFO_MC_DESC
 #include "ARMGenSubtargetInfo.inc"
 
-using namespace llvm;
 
 std::string ARM_MC::ParseARMTriple(StringRef TT, StringRef CPU) {
   Triple triple(TT);

lib/Target/Mips/AsmParser/MipsAsmParser.cpp

@@ -24,6 +24,10 @@
 
 using namespace llvm;
 
+namespace llvm {
+class MCInstrInfo;
+}
+
 namespace {
 class MipsAssemblerOptions {
 public:
@@ -201,8 +205,10 @@ class MipsAsmParser : public MCTargetAsmParser {
   bool processInstruction(MCInst &Inst, SMLoc IDLoc,
                         SmallVectorImpl<MCInst> &Instructions);
 public:
-  MipsAsmParser(MCSubtargetInfo &sti, MCAsmParser &parser)
+  MipsAsmParser(MCSubtargetInfo &sti, MCAsmParser &parser,
-    : MCTargetAsmParser(), STI(sti), Parser(parser), hasConsumedDollar(false) {
+                const MCInstrInfo &MII)
+      : MCTargetAsmParser(), STI(sti), Parser(parser),
+        hasConsumedDollar(false) {
     // Initialize the set of available features.
     setAvailableFeatures(ComputeAvailableFeatures(STI.getFeatureBits()));
   }

lib/Target/PowerPC/AsmParser/PPCAsmParser.cpp

@@ -218,8 +218,9 @@ class PPCAsmParser : public MCTargetAsmParser {
 
 
 public:
-  PPCAsmParser(MCSubtargetInfo &_STI, MCAsmParser &_Parser)
+  PPCAsmParser(MCSubtargetInfo &_STI, MCAsmParser &_Parser,
-    : MCTargetAsmParser(), STI(_STI), Parser(_Parser) {
+               const MCInstrInfo &MII)
+      : MCTargetAsmParser(), STI(_STI), Parser(_Parser) {
     // Check for 64-bit vs. 32-bit pointer mode.
     Triple TheTriple(STI.getTargetTriple());
     IsPPC64 = (TheTriple.getArch() == Triple::ppc64 ||

lib/Target/SystemZ/AsmParser/SystemZAsmParser.cpp

@@ -327,8 +327,9 @@ private:
                     StringRef Mnemonic);
 
 public:
-  SystemZAsmParser(MCSubtargetInfo &sti, MCAsmParser &parser)
+  SystemZAsmParser(MCSubtargetInfo &sti, MCAsmParser &parser,
-    : MCTargetAsmParser(), STI(sti), Parser(parser) {
+                   const MCInstrInfo &MII)
+      : MCTargetAsmParser(), STI(sti), Parser(parser) {
     MCAsmParserExtension::Initialize(Parser);
 
     // Initialize the set of available features.

lib/Target/X86/AsmParser/X86AsmParser.cpp

@@ -556,8 +556,9 @@ private:
   /// }
 
 public:
-  X86AsmParser(MCSubtargetInfo &sti, MCAsmParser &parser)
+  X86AsmParser(MCSubtargetInfo &sti, MCAsmParser &parser,
-    : MCTargetAsmParser(), STI(sti), Parser(parser), InstInfo(0) {
+               const MCInstrInfo &MII)
+      : MCTargetAsmParser(), STI(sti), Parser(parser), InstInfo(0) {
 
     // Initialize the set of available features.
     setAvailableFeatures(ComputeAvailableFeatures(STI.getFeatureBits()));

test/MC/ARM/deprecated-v8.s

@@ -1,3 +1,5 @@
 @ RUN: llvm-mc -triple armv8 -show-encoding < %s 2>&1 | FileCheck %s
 setend be
+@ CHECK: warning: deprecated
+mcr p8, #0, r5, c7, c5, #4
 @ CHECK: warning: deprecated on armv8

tools/llvm-mc/llvm-mc.cpp

@@ -319,10 +319,10 @@ static int AsLexInput(SourceMgr &SrcMgr, MCAsmInfo &MAI, tool_output_file *Out)
 
 static int AssembleInput(const char *ProgName, const Target *TheTarget, 
                          SourceMgr &SrcMgr, MCContext &Ctx, MCStreamer &Str,
-                         MCAsmInfo &MAI, MCSubtargetInfo &STI) {
+                         MCAsmInfo &MAI, MCSubtargetInfo &STI, MCInstrInfo &MCII) {
   OwningPtr<MCAsmParser> Parser(createMCAsmParser(SrcMgr, Ctx,
                                                   Str, MAI));
-  OwningPtr<MCTargetAsmParser> TAP(TheTarget->createMCAsmParser(STI, *Parser));
+  OwningPtr<MCTargetAsmParser> TAP(TheTarget->createMCAsmParser(STI, *Parser, MCII));
   if (!TAP) {
     errs() << ProgName
            << ": error: this target does not support assembly parsing.\n";
@@ -459,7 +459,7 @@ int main(int argc, char **argv) {
     Res = AsLexInput(SrcMgr, *MAI, Out.get());
     break;
   case AC_Assemble:
-    Res = AssembleInput(ProgName, TheTarget, SrcMgr, Ctx, *Str, *MAI, *STI);
+    Res = AssembleInput(ProgName, TheTarget, SrcMgr, Ctx, *Str, *MAI, *STI, *MCII);
     break;
   case AC_MDisassemble:
     assert(IP && "Expected assembly output");

utils/TableGen/AsmMatcherEmitter.cpp

@@ -430,6 +430,9 @@ struct MatchableInfo {
   /// function.
   std::string ConversionFnKind;
 
+  /// If this instruction is deprecated in some form.
+  bool HasDeprecation;
+
   MatchableInfo(const CodeGenInstruction &CGI)
     : AsmVariantID(0), TheDef(CGI.TheDef), DefRec(&CGI),
       AsmString(CGI.AsmString) {
@@ -779,6 +782,13 @@ void MatchableInfo::initialize(const AsmMatcherInfo &Info,
     if (Record *Reg = AsmOperands[i].SingletonReg)
       SingletonRegisters.insert(Reg);
   }
+
+  const RecordVal *DepMask = TheDef->getValue("DeprecatedFeatureMask");
+  if (!DepMask)
+    DepMask = TheDef->getValue("ComplexDeprecationPredicate");
+
+  HasDeprecation =
+      DepMask ? !DepMask->getValue()->getAsUnquotedString().empty() : false;
 }
 
 /// tokenizeAsmString - Tokenize a simplified assembly string.
@@ -2743,11 +2753,13 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
 
   size_t MaxNumOperands = 0;
   unsigned MaxMnemonicIndex = 0;
+  bool HasDeprecation = false;
   for (std::vector<MatchableInfo*>::const_iterator it =
          Info.Matchables.begin(), ie = Info.Matchables.end();
        it != ie; ++it) {
     MatchableInfo &II = **it;
     MaxNumOperands = std::max(MaxNumOperands, II.AsmOperands.size());
+    HasDeprecation |= II.HasDeprecation;
 
     // Store a pascal-style length byte in the mnemonic.
     std::string LenMnemonic = char(II.Mnemonic.size()) + II.Mnemonic.str();
@@ -3018,6 +3030,14 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   if (!InsnCleanupFn.empty())
     OS << "    " << InsnCleanupFn << "(Inst);\n";
 
+  if (HasDeprecation) {
+    OS << "    std::string Info;\n";
+    OS << "    if (MII.get(Inst.getOpcode()).getDeprecatedInfo(Inst, STI, Info)) {\n";
+    OS << "      SMLoc Loc = ((" << Target.getName() << "Operand*)Operands[0])->getStartLoc();\n";
+    OS << "      Parser.Warning(Loc, Info, None);\n";
+    OS << "    }\n";
+  }
+
   OS << "    return Match_Success;\n";
   OS << "  }\n\n";
 

utils/TableGen/CodeGenInstruction.cpp

@@ -337,6 +337,20 @@ CodeGenInstruction::CodeGenInstruction(Record *R)
 
   // Parse the DisableEncoding field.
   Operands.ProcessDisableEncoding(R->getValueAsString("DisableEncoding"));
+
+  // First check for a ComplexDeprecationPredicate.
+  if (R->getValue("ComplexDeprecationPredicate")) {
+    HasComplexDeprecationPredicate = true;
+    DeprecatedReason = R->getValueAsString("ComplexDeprecationPredicate");
+  } else if (RecordVal *Dep = R->getValue("DeprecatedFeatureMask")) {
+    // Check if we have a Subtarget feature mask.
+    HasComplexDeprecationPredicate = false;
+    DeprecatedReason = Dep->getValue()->getAsString();
+  } else {
+    // This instruction isn't deprecated.
+    HasComplexDeprecationPredicate = false;
+    DeprecatedReason = "";
+  }
 }
 
 /// HasOneImplicitDefWithKnownVT - If the instruction has at least one

utils/TableGen/CodeGenInstruction.h

@@ -248,6 +248,9 @@ namespace llvm {
     bool isCodeGenOnly;
     bool isPseudo;
 
+    std::string DeprecatedReason;
+    bool HasComplexDeprecationPredicate;
+
     /// Are there any undefined flags?
     bool hasUndefFlags() const {
       return mayLoad_Unset || mayStore_Unset || hasSideEffects_Unset;

utils/TableGen/InstrInfoEmitter.cpp

@@ -514,6 +514,19 @@ void InstrInfoEmitter::emitRecord(const CodeGenInstruction &Inst, unsigned Num,
   else
     OS << "OperandInfo" << OpInfo.find(OperandInfo)->second;
 
+  CodeGenTarget &Target = CDP.getTargetInfo();
+  if (Inst.HasComplexDeprecationPredicate)
+    // Emit a function pointer to the complex predicate method.
+    OS << ",0"
+       << ",&get" << Inst.DeprecatedReason << "DeprecationInfo";
+  else if (!Inst.DeprecatedReason.empty())
+    // Emit the Subtarget feature.
+    OS << "," << Target.getInstNamespace() << "::" << Inst.DeprecatedReason
+       << ",0";
+  else
+    // Instruction isn't deprecated.
+    OS << ",0,0";
+
   OS << " },  // Inst #" << Num << " = " << Inst.TheDef->getName() << "\n";
 }