Update llvm to trunk r256633.

1 files changed, 195 insertions, 177 deletions

diff --git a/contrib/llvm/utils/TableGen/AsmMatcherEmitter.cpp b/contrib/llvm/utils/TableGen/AsmMatcherEmitter.cpp
index 0d7c5ffbea1c..4177388840be 100644
--- a/contrib/llvm/utils/TableGen/AsmMatcherEmitter.cpp
+++ b/contrib/llvm/utils/TableGen/AsmMatcherEmitter.cpp
@@ -294,6 +294,15 @@ public:
   }
 };
 
+class AsmVariantInfo {
+public:
+  std::string RegisterPrefix;
+  std::string TokenizingCharacters;
+  std::string SeparatorCharacters;
+  std::string BreakCharacters;
+  int AsmVariantNo;
+};
+
 /// MatchableInfo - Helper class for storing the necessary information for an
 /// instruction or alias which is capable of being matched.
 struct MatchableInfo {
@@ -460,6 +469,20 @@ struct MatchableInfo {
         TheDef->getValueAsBit("UseInstAsmMatchConverter")) {
   }
 
+  // Could remove this and the dtor if PointerUnion supported unique_ptr
+  // elements with a dynamic failure/assertion (like the one below) in the case
+  // where it was copied while being in an owning state.
+  MatchableInfo(const MatchableInfo &RHS)
+      : AsmVariantID(RHS.AsmVariantID), AsmString(RHS.AsmString),
+        TheDef(RHS.TheDef), DefRec(RHS.DefRec), ResOperands(RHS.ResOperands),
+        Mnemonic(RHS.Mnemonic), AsmOperands(RHS.AsmOperands),
+        RequiredFeatures(RHS.RequiredFeatures),
+        ConversionFnKind(RHS.ConversionFnKind),
+        HasDeprecation(RHS.HasDeprecation),
+        UseInstAsmMatchConverter(RHS.UseInstAsmMatchConverter) {
+    assert(!DefRec.is<const CodeGenInstAlias *>());
+  }
+
   ~MatchableInfo() {
     delete DefRec.dyn_cast<const CodeGenInstAlias*>();
   }
@@ -470,18 +493,12 @@ struct MatchableInfo {
 
   void initialize(const AsmMatcherInfo &Info,
                   SmallPtrSetImpl<Record*> &SingletonRegisters,
-                  int AsmVariantNo, std::string &RegisterPrefix);
+                  AsmVariantInfo const &Variant);
 
   /// validate - Return true if this matchable is a valid thing to match against
   /// and perform a bunch of validity checking.
   bool validate(StringRef CommentDelimiter, bool Hack) const;
 
-  /// extractSingletonRegisterForAsmOperand - Extract singleton register,
-  /// if present, from specified token.
-  void
-  extractSingletonRegisterForAsmOperand(unsigned i, const AsmMatcherInfo &Info,
-                                        std::string &RegisterPrefix);
-
   /// findAsmOperand - Find the AsmOperand with the specified name and
   /// suboperand index.
   int findAsmOperand(StringRef N, int SubOpIdx) const {
@@ -576,8 +593,10 @@ struct MatchableInfo {
   void dump() const;
 
 private:
-  void tokenizeAsmString(const AsmMatcherInfo &Info);
-  void addAsmOperand(size_t Start, size_t End);
+  void tokenizeAsmString(AsmMatcherInfo const &Info,
+                         AsmVariantInfo const &Variant);
+  void addAsmOperand(size_t Start, size_t End,
+                     std::string const &SeparatorCharacters);
 };
 
 /// SubtargetFeatureInfo - Helper class for storing information on a subtarget
@@ -756,8 +775,7 @@ void MatchableInfo::formTwoOperandAlias(StringRef Constraint) {
 
   // Find the ResOperand that refers to the operand we're aliasing away
   // and update it to refer to the combined operand instead.
-  for (unsigned i = 0, e = ResOperands.size(); i != e; ++i) {
-    ResOperand &Op = ResOperands[i];
+  for (ResOperand &Op : ResOperands) {
     if (Op.Kind == ResOperand::RenderAsmOperand &&
         Op.AsmOperandNum == (unsigned)SrcAsmOperand) {
       Op.AsmOperandNum = DstAsmOperand;
@@ -768,8 +786,7 @@ void MatchableInfo::formTwoOperandAlias(StringRef Constraint) {
   AsmOperands.erase(AsmOperands.begin() + SrcAsmOperand);
   // Adjust the ResOperand references to any AsmOperands that followed
   // the one we just deleted.
-  for (unsigned i = 0, e = ResOperands.size(); i != e; ++i) {
-    ResOperand &Op = ResOperands[i];
+  for (ResOperand &Op : ResOperands) {
     switch(Op.Kind) {
     default:
       // Nothing to do for operands that don't reference AsmOperands.
@@ -786,26 +803,58 @@ void MatchableInfo::formTwoOperandAlias(StringRef Constraint) {
   }
 }
 
+/// extractSingletonRegisterForAsmOperand - Extract singleton register,
+/// if present, from specified token.
+static void
+extractSingletonRegisterForAsmOperand(MatchableInfo::AsmOperand &Op,
+                                      const AsmMatcherInfo &Info,
+                                      StringRef RegisterPrefix) {
+  StringRef Tok = Op.Token;
+
+  // If this token is not an isolated token, i.e., it isn't separated from
+  // other tokens (e.g. with whitespace), don't interpret it as a register name.
+  if (!Op.IsIsolatedToken)
+    return;
+
+  if (RegisterPrefix.empty()) {
+    std::string LoweredTok = Tok.lower();
+    if (const CodeGenRegister *Reg = Info.Target.getRegisterByName(LoweredTok))
+      Op.SingletonReg = Reg->TheDef;
+    return;
+  }
+
+  if (!Tok.startswith(RegisterPrefix))
+    return;
+
+  StringRef RegName = Tok.substr(RegisterPrefix.size());
+  if (const CodeGenRegister *Reg = Info.Target.getRegisterByName(RegName))
+    Op.SingletonReg = Reg->TheDef;
+
+  // If there is no register prefix (i.e. "%" in "%eax"), then this may
+  // be some random non-register token, just ignore it.
+  return;
+}
+
 void MatchableInfo::initialize(const AsmMatcherInfo &Info,
                                SmallPtrSetImpl<Record*> &SingletonRegisters,
-                               int AsmVariantNo, std::string &RegisterPrefix) {
-  AsmVariantID = AsmVariantNo;
+                               AsmVariantInfo const &Variant) {
+  AsmVariantID = Variant.AsmVariantNo;
   AsmString =
-    CodeGenInstruction::FlattenAsmStringVariants(AsmString, AsmVariantNo);
+    CodeGenInstruction::FlattenAsmStringVariants(AsmString,
+                                                 Variant.AsmVariantNo);
 
-  tokenizeAsmString(Info);
+  tokenizeAsmString(Info, Variant);
 
   // Compute the require features.
-  std::vector<Record*> Predicates =TheDef->getValueAsListOfDefs("Predicates");
-  for (unsigned i = 0, e = Predicates.size(); i != e; ++i)
+  for (Record *Predicate : TheDef->getValueAsListOfDefs("Predicates"))
     if (const SubtargetFeatureInfo *Feature =
-            Info.getSubtargetFeature(Predicates[i]))
+            Info.getSubtargetFeature(Predicate))
       RequiredFeatures.push_back(Feature);
 
   // Collect singleton registers, if used.
-  for (unsigned i = 0, e = AsmOperands.size(); i != e; ++i) {
-    extractSingletonRegisterForAsmOperand(i, Info, RegisterPrefix);
-    if (Record *Reg = AsmOperands[i].SingletonReg)
+  for (MatchableInfo::AsmOperand &Op : AsmOperands) {
+    extractSingletonRegisterForAsmOperand(Op, Info, Variant.RegisterPrefix);
+    if (Record *Reg = Op.SingletonReg)
       SingletonRegisters.insert(Reg);
   }
 
@@ -818,9 +867,9 @@ void MatchableInfo::initialize(const AsmMatcherInfo &Info,
 }
 
 /// Append an AsmOperand for the given substring of AsmString.
-void MatchableInfo::addAsmOperand(size_t Start, size_t End) {
+void MatchableInfo::addAsmOperand(size_t Start, size_t End,
+                                  std::string const &Separators) {
   StringRef String = AsmString;
-  StringRef Separators = "[]*! \t,";
   // Look for separators before and after to figure out is this token is
   // isolated.  Accept '$$' as that's how we escape '$'.
   bool IsIsolatedToken =
@@ -831,92 +880,86 @@ void MatchableInfo::addAsmOperand(size_t Start, size_t End) {
 }
 
 /// tokenizeAsmString - Tokenize a simplified assembly string.
-void MatchableInfo::tokenizeAsmString(const AsmMatcherInfo &Info) {
+void MatchableInfo::tokenizeAsmString(const AsmMatcherInfo &Info,
+                                      AsmVariantInfo const &Variant) {
   StringRef String = AsmString;
-  unsigned Prev = 0;
-  bool InTok = true;
-  for (unsigned i = 0, e = String.size(); i != e; ++i) {
-    switch (String[i]) {
-    case '[':
-    case ']':
-    case '*':
-    case '!':
-    case ' ':
-    case '\t':
-    case ',':
-      if (InTok) {
-        addAsmOperand(Prev, i);
+  size_t Prev = 0;
+  bool InTok = false;
+  std::string Separators = Variant.TokenizingCharacters +
+                           Variant.SeparatorCharacters;
+  for (size_t i = 0, e = String.size(); i != e; ++i) {
+    if(Variant.BreakCharacters.find(String[i]) != std::string::npos) {
+      if(InTok) {
+        addAsmOperand(Prev, i, Separators);
+        Prev = i;
+      }
+      InTok = true;
+      continue;
+    }
+    if(Variant.TokenizingCharacters.find(String[i]) != std::string::npos) {
+      if(InTok) {
+        addAsmOperand(Prev, i, Separators);
         InTok = false;
       }
-      if (!isspace(String[i]) && String[i] != ',')
-        addAsmOperand(i, i + 1);
+      addAsmOperand(i, i + 1, Separators);
       Prev = i + 1;
-      break;
-
+      continue;
+    }
+    if(Variant.SeparatorCharacters.find(String[i]) != std::string::npos) {
+      if(InTok) {
+        addAsmOperand(Prev, i, Separators);
+        InTok = false;
+      }
+      Prev = i + 1;
+      continue;
+    }
+    switch (String[i]) {
     case '\\':
       if (InTok) {
-        addAsmOperand(Prev, i);
+        addAsmOperand(Prev, i, Separators);
         InTok = false;
       }
       ++i;
       assert(i != String.size() && "Invalid quoted character");
-      addAsmOperand(i, i + 1);
+      addAsmOperand(i, i + 1, Separators);
       Prev = i + 1;
       break;
 
     case '$': {
-      if (InTok) {
-        addAsmOperand(Prev, i);
+      if (InTok && Prev != i) {
+        addAsmOperand(Prev, i, Separators);
         InTok = false;
       }
 
-      // If this isn't "${", treat like a normal token.
+      // If this isn't "${", start new identifier looking like "$xxx"
       if (i + 1 == String.size() || String[i + 1] != '{') {
         Prev = i;
         break;
       }
 
-      StringRef::iterator End = std::find(String.begin() + i, String.end(),'}');
-      assert(End != String.end() && "Missing brace in operand reference!");
-      size_t EndPos = End - String.begin();
-      addAsmOperand(i, EndPos+1);
+      size_t EndPos = String.find('}', i);
+      assert(EndPos != StringRef::npos &&
+             "Missing brace in operand reference!");
+      addAsmOperand(i, EndPos+1, Separators);
       Prev = EndPos + 1;
       i = EndPos;
       break;
     }
-
-    case '.':
-      if (!Info.AsmParser->getValueAsBit("MnemonicContainsDot")) {
-        if (InTok)
-          addAsmOperand(Prev, i);
-        Prev = i;
-      }
-      InTok = true;
-      break;
-
     default:
       InTok = true;
     }
   }
   if (InTok && Prev != String.size())
-    addAsmOperand(Prev, StringRef::npos);
+    addAsmOperand(Prev, StringRef::npos, Separators);
 
   // The first token of the instruction is the mnemonic, which must be a
   // simple string, not a $foo variable or a singleton register.
   if (AsmOperands.empty())
     PrintFatalError(TheDef->getLoc(),
                   "Instruction '" + TheDef->getName() + "' has no tokens");
-  Mnemonic = AsmOperands[0].Token;
-  if (Mnemonic.empty())
-    PrintFatalError(TheDef->getLoc(),
-                  "Missing instruction mnemonic");
-  // FIXME : Check and raise an error if it is a register.
-  if (Mnemonic[0] == '$')
-    PrintFatalError(TheDef->getLoc(),
-                    "Invalid instruction mnemonic '" + Mnemonic + "'!");
-
-  // Remove the first operand, it is tracked in the mnemonic field.
-  AsmOperands.erase(AsmOperands.begin());
+  assert(!AsmOperands[0].Token.empty());
+  if (AsmOperands[0].Token[0] != '$')
+    Mnemonic = AsmOperands[0].Token;
 }
 
 bool MatchableInfo::validate(StringRef CommentDelimiter, bool Hack) const {
@@ -946,8 +989,8 @@ bool MatchableInfo::validate(StringRef CommentDelimiter, bool Hack) const {
   // Also, check for instructions which reference the operand multiple times;
   // this implies a constraint we would not honor.
   std::set<std::string> OperandNames;
-  for (unsigned i = 0, e = AsmOperands.size(); i != e; ++i) {
-    StringRef Tok = AsmOperands[i].Token;
+  for (const AsmOperand &Op : AsmOperands) {
+    StringRef Tok = Op.Token;
     if (Tok[0] == '$' && Tok.find(':') != StringRef::npos)
       PrintFatalError(TheDef->getLoc(),
                       "matchable with operand modifier '" + Tok +
@@ -974,38 +1017,6 @@ bool MatchableInfo::validate(StringRef CommentDelimiter, bool Hack) const {
   return true;
 }
 
-/// extractSingletonRegisterForAsmOperand - Extract singleton register,
-/// if present, from specified token.
-void MatchableInfo::
-extractSingletonRegisterForAsmOperand(unsigned OperandNo,
-                                      const AsmMatcherInfo &Info,
-                                      std::string &RegisterPrefix) {
-  StringRef Tok = AsmOperands[OperandNo].Token;
-
-  // If this token is not an isolated token, i.e., it isn't separated from
-  // other tokens (e.g. with whitespace), don't interpret it as a register name.
-  if (!AsmOperands[OperandNo].IsIsolatedToken)
-    return;
-
-  if (RegisterPrefix.empty()) {
-    std::string LoweredTok = Tok.lower();
-    if (const CodeGenRegister *Reg = Info.Target.getRegisterByName(LoweredTok))
-      AsmOperands[OperandNo].SingletonReg = Reg->TheDef;
-    return;
-  }
-
-  if (!Tok.startswith(RegisterPrefix))
-    return;
-
-  StringRef RegName = Tok.substr(RegisterPrefix.size());
-  if (const CodeGenRegister *Reg = Info.Target.getRegisterByName(RegName))
-    AsmOperands[OperandNo].SingletonReg = Reg->TheDef;
-
-  // If there is no register prefix (i.e. "%" in "%eax"), then this may
-  // be some random non-register token, just ignore it.
-  return;
-}
-
 static std::string getEnumNameForToken(StringRef Str) {
   std::string Res;
 
@@ -1364,8 +1375,15 @@ void AsmMatcherInfo::buildInfo() {
     Record *AsmVariant = Target.getAsmParserVariant(VC);
     std::string CommentDelimiter =
       AsmVariant->getValueAsString("CommentDelimiter");
-    std::string RegisterPrefix = AsmVariant->getValueAsString("RegisterPrefix");
-    int AsmVariantNo = AsmVariant->getValueAsInt("Variant");
+    AsmVariantInfo Variant;
+    Variant.RegisterPrefix = AsmVariant->getValueAsString("RegisterPrefix");
+    Variant.TokenizingCharacters =
+        AsmVariant->getValueAsString("TokenizingCharacters");
+    Variant.SeparatorCharacters =
+        AsmVariant->getValueAsString("SeparatorCharacters");
+    Variant.BreakCharacters =
+        AsmVariant->getValueAsString("BreakCharacters");
+    Variant.AsmVariantNo = AsmVariant->getValueAsInt("Variant");
 
     for (const CodeGenInstruction *CGI : Target.instructions()) {
 
@@ -1378,9 +1396,9 @@ void AsmMatcherInfo::buildInfo() {
       if (CGI->TheDef->getValueAsBit("isCodeGenOnly"))
         continue;
 
-      std::unique_ptr<MatchableInfo> II(new MatchableInfo(*CGI));
+      auto II = llvm::make_unique<MatchableInfo>(*CGI);
 
-      II->initialize(*this, SingletonRegisters, AsmVariantNo, RegisterPrefix);
+      II->initialize(*this, SingletonRegisters, Variant);
 
       // Ignore instructions which shouldn't be matched and diagnose invalid
       // instruction definitions with an error.
@@ -1396,7 +1414,8 @@ void AsmMatcherInfo::buildInfo() {
       Records.getAllDerivedDefinitions("InstAlias");
     for (unsigned i = 0, e = AllInstAliases.size(); i != e; ++i) {
       auto Alias = llvm::make_unique<CodeGenInstAlias>(AllInstAliases[i],
-                                                       AsmVariantNo, Target);
+                                                       Variant.AsmVariantNo,
+                                                       Target);
 
       // If the tblgen -match-prefix option is specified (for tblgen hackers),
       // filter the set of instruction aliases we consider, based on the target
@@ -1405,9 +1424,9 @@ void AsmMatcherInfo::buildInfo() {
             .startswith( MatchPrefix))
         continue;
 
-      std::unique_ptr<MatchableInfo> II(new MatchableInfo(std::move(Alias)));
+      auto II = llvm::make_unique<MatchableInfo>(std::move(Alias));
 
-      II->initialize(*this, SingletonRegisters, AsmVariantNo, RegisterPrefix);
+      II->initialize(*this, SingletonRegisters, Variant);
 
       // Validate the alias definitions.
       II->validate(CommentDelimiter, false);
@@ -1434,7 +1453,7 @@ void AsmMatcherInfo::buildInfo() {
       StringRef Token = Op.Token;
 
       // Check for singleton registers.
-      if (Record *RegRecord = II->AsmOperands[i].SingletonReg) {
+      if (Record *RegRecord = Op.SingletonReg) {
         Op.Class = RegisterClasses[RegRecord];
         assert(Op.Class && Op.Class->Registers.size() == 1 &&
                "Unexpected class for singleton register");
@@ -1474,7 +1493,7 @@ void AsmMatcherInfo::buildInfo() {
         II->TheDef->getValueAsString("TwoOperandAliasConstraint");
       if (Constraint != "") {
         // Start by making a copy of the original matchable.
-        std::unique_ptr<MatchableInfo> AliasII(new MatchableInfo(*II));
+        auto AliasII = llvm::make_unique<MatchableInfo>(*II);
 
         // Adjust it to be a two-operand alias.
         AliasII->formTwoOperandAlias(Constraint);
@@ -1494,8 +1513,7 @@ void AsmMatcherInfo::buildInfo() {
   // information.
   std::vector<Record*> AllTokenAliases =
     Records.getAllDerivedDefinitions("TokenAlias");
-  for (unsigned i = 0, e = AllTokenAliases.size(); i != e; ++i) {
-    Record *Rec = AllTokenAliases[i];
+  for (Record *Rec : AllTokenAliases) {
     ClassInfo *FromClass = getTokenClass(Rec->getValueAsString("FromToken"));
     ClassInfo *ToClass = getTokenClass(Rec->getValueAsString("ToToken"));
     if (FromClass == ToClass)
@@ -1603,9 +1621,7 @@ void MatchableInfo::buildInstructionResultOperands() {
 
   // Loop over all operands of the result instruction, determining how to
   // populate them.
-  for (unsigned i = 0, e = ResultInst->Operands.size(); i != e; ++i) {
-    const CGIOperandList::OperandInfo &OpInfo = ResultInst->Operands[i];
-
+  for (const CGIOperandList::OperandInfo &OpInfo : ResultInst->Operands) {
     // If this is a tied operand, just copy from the previously handled operand.
     int TiedOp = -1;
     if (OpInfo.MINumOperands == 1)
@@ -1701,7 +1717,7 @@ void MatchableInfo::buildAliasResultOperands() {
 }
 
 static unsigned getConverterOperandID(const std::string &Name,
-                                      SetVector<std::string> &Table,
+                                      SmallSetVector<std::string, 16> &Table,
                                       bool &IsNew) {
   IsNew = Table.insert(Name);
 
@@ -1717,8 +1733,8 @@ static unsigned getConverterOperandID(const std::string &Name,
 static void emitConvertFuncs(CodeGenTarget &Target, StringRef ClassName,
                              std::vector<std::unique_ptr<MatchableInfo>> &Infos,
                              raw_ostream &OS) {
-  SetVector<std::string> OperandConversionKinds;
-  SetVector<std::string> InstructionConversionKinds;
+  SmallSetVector<std::string, 16> OperandConversionKinds;
+  SmallSetVector<std::string, 16> InstructionConversionKinds;
   std::vector<std::vector<uint8_t> > ConversionTable;
   size_t MaxRowLength = 2; // minimum is custom converter plus terminator.
 
@@ -1850,7 +1866,7 @@ static void emitConvertFuncs(CodeGenTarget &Target, StringRef ClassName,
 
         // Add the operand entry to the instruction kind conversion row.
         ConversionRow.push_back(ID);
-        ConversionRow.push_back(OpInfo.AsmOperandNum + 1);
+        ConversionRow.push_back(OpInfo.AsmOperandNum);
 
         if (!IsNewConverter)
           break;
@@ -1959,7 +1975,7 @@ static void emitConvertFuncs(CodeGenTarget &Target, StringRef ClassName,
       continue;
 
     // Add the row to the table.
-    ConversionTable.push_back(ConversionRow);
+    ConversionTable.push_back(std::move(ConversionRow));
   }
 
   // Finish up the converter driver function.
@@ -1979,10 +1995,8 @@ static void emitConvertFuncs(CodeGenTarget &Target, StringRef ClassName,
 
   // Output the instruction conversion kind enum.
   OS << "enum InstructionConversionKind {\n";
-  for (SetVector<std::string>::const_iterator
-         i = InstructionConversionKinds.begin(),
-         e = InstructionConversionKinds.end(); i != e; ++i)
-    OS << "  " << *i << ",\n";
+  for (const std::string &Signature : InstructionConversionKinds)
+    OS << "  " << Signature << ",\n";
   OS << "  CVT_NUM_SIGNATURES\n";
   OS << "};\n\n";
 
@@ -2105,12 +2119,7 @@ static void emitIsSubclass(CodeGenTarget &Target,
   OS << "  if (A == B)\n";
   OS << "    return true;\n\n";
 
-  std::string OStr;
-  raw_string_ostream SS(OStr);
-  unsigned Count = 0;
-  SS << "  switch (A) {\n";
-  SS << "  default:\n";
-  SS << "    return false;\n";
+  bool EmittedSwitch = false;
   for (const auto &A : Infos) {
     std::vector<StringRef> SuperClasses;
     for (const auto &B : Infos) {
@@ -2120,33 +2129,38 @@ static void emitIsSubclass(CodeGenTarget &Target,
 
     if (SuperClasses.empty())
       continue;
-    ++Count;
 
-    SS << "\n  case " << A.Name << ":\n";
+    // If this is the first SuperClass, emit the switch header.
+    if (!EmittedSwitch) {
+      OS << "  switch (A) {\n";
+      OS << "  default:\n";
+      OS << "    return false;\n";
+      EmittedSwitch = true;
+    }
+
+    OS << "\n  case " << A.Name << ":\n";
 
     if (SuperClasses.size() == 1) {
-      SS << "    return B == " << SuperClasses.back().str() << ";\n";
+      OS << "    return B == " << SuperClasses.back() << ";\n";
       continue;
     }
 
     if (!SuperClasses.empty()) {
-      SS << "    switch (B) {\n";
-      SS << "    default: return false;\n";
-      for (unsigned i = 0, e = SuperClasses.size(); i != e; ++i)
-        SS << "    case " << SuperClasses[i].str() << ": return true;\n";
-      SS << "    }\n";
+      OS << "    switch (B) {\n";
+      OS << "    default: return false;\n";
+      for (StringRef SC : SuperClasses)
+        OS << "    case " << SC << ": return true;\n";
+      OS << "    }\n";
     } else {
       // No case statement to emit
-      SS << "    return false;\n";
+      OS << "    return false;\n";
     }
   }
-  SS << "  }\n";
+  OS << "  }\n";
 
-  // If there were case statements emitted into the string stream, write them
-  // to the output stream, otherwise write the default.
-  if (Count)
-    OS << SS.str();
-  else
+  // If there were case statements emitted into the string stream write the
+  // default.
+  if (!EmittedSwitch)
     OS << "  return false;\n";
 
   OS << "}\n\n";
@@ -2575,13 +2589,17 @@ static void emitCustomOperandParsing(raw_ostream &OS, CodeGenTarget &Target,
   OS << "  uint64_t AvailableFeatures = getAvailableFeatures();\n\n";
 
   OS << "  // Get the next operand index.\n";
-  OS << "  unsigned NextOpNum = Operands.size()-1;\n";
+  OS << "  unsigned NextOpNum = Operands.size();\n";
 
   // Emit code to search the table.
   OS << "  // Search the table.\n";
   OS << "  std::pair<const OperandMatchEntry*, const OperandMatchEntry*>";
-  OS << " MnemonicRange =\n";
-  OS << "    std::equal_range(OperandMatchTable, OperandMatchTable+"
+  OS << " MnemonicRange\n";
+  OS << "       (OperandMatchTable, OperandMatchTable+";
+  OS << Info.OperandMatchInfo.size() << ");\n";
+  OS << "  if(!Mnemonic.empty())\n";
+  OS << "    MnemonicRange = std::equal_range(OperandMatchTable,";
+  OS << " OperandMatchTable+"
      << Info.OperandMatchInfo.size() << ", Mnemonic,\n"
      << "                     LessOpcodeOperand());\n\n";
 
@@ -2682,7 +2700,7 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
      << "&Operands);\n";
   OS << "  void convertToMapAndConstraints(unsigned Kind,\n                ";
   OS << "           const OperandVector &Operands) override;\n";
-  OS << "  bool mnemonicIsValid(StringRef Mnemonic, unsigned VariantID) override;\n";
+  OS << "  bool mnemonicIsValid(StringRef Mnemonic, unsigned VariantID);\n";
   OS << "  unsigned MatchInstructionImpl(const OperandVector &Operands,\n"
      << "                                MCInst &Inst,\n"
      << "                                uint64_t &ErrorInfo,"
@@ -2891,8 +2909,8 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
      << "                     bool matchingInlineAsm, unsigned VariantID) {\n";
 
   OS << "  // Eliminate obvious mismatches.\n";
-  OS << "  if (Operands.size() > " << (MaxNumOperands+1) << ") {\n";
-  OS << "    ErrorInfo = " << (MaxNumOperands+1) << ";\n";
+  OS << "  if (Operands.size() > " << MaxNumOperands << ") {\n";
+  OS << "    ErrorInfo = " << MaxNumOperands << ";\n";
   OS << "    return Match_InvalidOperand;\n";
   OS << "  }\n\n";
 
@@ -2901,7 +2919,9 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   OS << "  uint64_t AvailableFeatures = getAvailableFeatures();\n\n";
 
   OS << "  // Get the instruction mnemonic, which is the first token.\n";
-  OS << "  StringRef Mnemonic = ((" << Target.getName()
+  OS << "  StringRef Mnemonic;\n";
+  OS << "  if (Operands[0]->isToken())\n";
+  OS << "    Mnemonic = ((" << Target.getName()
      << "Operand&)*Operands[0]).getToken();\n\n";
 
   if (HasMnemonicAliases) {
@@ -2932,8 +2952,11 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   }
   OS << "  }\n";
   OS << "  // Search the table.\n";
-  OS << "  std::pair<const MatchEntry*, const MatchEntry*> MnemonicRange =\n";
-  OS << "    std::equal_range(Start, End, Mnemonic, LessOpcode());\n\n";
+  OS << "  std::pair<const MatchEntry*, const MatchEntry*> "
+        "MnemonicRange(Start, End);\n";
+  OS << "  unsigned SIndex = Mnemonic.empty() ? 0 : 1;\n";
+  OS << "  if (!Mnemonic.empty())\n";
+  OS << "    MnemonicRange = std::equal_range(Start, End, Mnemonic.lower(), LessOpcode());\n\n";
 
   OS << "  // Return a more specific error code if no mnemonics match.\n";
   OS << "  if (MnemonicRange.first == MnemonicRange.second)\n";
@@ -2943,28 +2966,23 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
      << "*ie = MnemonicRange.second;\n";
   OS << "       it != ie; ++it) {\n";
 
-  OS << "    // equal_range guarantees that instruction mnemonic matches.\n";
-  OS << "    assert(Mnemonic == it->getMnemonic());\n";
-
   // Emit check that the subclasses match.
   OS << "    bool OperandsValid = true;\n";
-  OS << "    for (unsigned i = 0; i != " << MaxNumOperands << "; ++i) {\n";
-  OS << "      if (i + 1 >= Operands.size()) {\n";
-  OS << "        OperandsValid = (it->Classes[i] == " <<"InvalidMatchClass);\n";
-  OS << "        if (!OperandsValid) ErrorInfo = i + 1;\n";
+  OS << "    for (unsigned i = SIndex; i != " << MaxNumOperands << "; ++i) {\n";
+  OS << "      auto Formal = static_cast<MatchClassKind>(it->Classes[i]);\n";
+  OS << "      if (i >= Operands.size()) {\n";
+  OS << "        OperandsValid = (Formal == " <<"InvalidMatchClass);\n";
+  OS << "        if (!OperandsValid) ErrorInfo = i;\n";
   OS << "        break;\n";
   OS << "      }\n";
-  OS << "      unsigned Diag = validateOperandClass(*Operands[i+1],\n";
-  OS.indent(43);
-  OS << "(MatchClassKind)it->Classes[i]);\n";
+  OS << "      MCParsedAsmOperand &Actual = *Operands[i];\n";
+  OS << "      unsigned Diag = validateOperandClass(Actual, Formal);\n";
   OS << "      if (Diag == Match_Success)\n";
   OS << "        continue;\n";
   OS << "      // If the generic handler indicates an invalid operand\n";
   OS << "      // failure, check for a special case.\n";
   OS << "      if (Diag == Match_InvalidOperand) {\n";
-  OS << "        Diag = validateTargetOperandClass(*Operands[i+1],\n";
-  OS.indent(43);
-  OS << "(MatchClassKind)it->Classes[i]);\n";
+  OS << "        Diag = validateTargetOperandClass(Actual, Formal);\n";
   OS << "        if (Diag == Match_Success)\n";
   OS << "          continue;\n";
   OS << "      }\n";
@@ -2973,8 +2991,8 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
   OS << "      // If we already had a match that only failed due to a\n";
   OS << "      // target predicate, that diagnostic is preferred.\n";
   OS << "      if (!HadMatchOtherThanPredicate &&\n";
-  OS << "          (it == MnemonicRange.first || ErrorInfo <= i+1)) {\n";
-  OS << "        ErrorInfo = i+1;\n";
+  OS << "          (it == MnemonicRange.first || ErrorInfo <= i)) {\n";
+  OS << "        ErrorInfo = i;\n";
   OS << "        // InvalidOperand is the default. Prefer specificity.\n";
   OS << "        if (Diag != Match_InvalidOperand)\n";
   OS << "          RetCode = Diag;\n";
@@ -3029,7 +3047,7 @@ void AsmMatcherEmitter::run(raw_ostream &OS) {
 
   if (HasDeprecation) {
     OS << "    std::string Info;\n";
-    OS << "    if (MII.get(Inst.getOpcode()).getDeprecatedInfo(Inst, STI, Info)) {\n";
+    OS << "    if (MII.get(Inst.getOpcode()).getDeprecatedInfo(Inst, getSTI(), Info)) {\n";
     OS << "      SMLoc Loc = ((" << Target.getName()
        << "Operand&)*Operands[0]).getStartLoc();\n";
     OS << "      getParser().Warning(Loc, Info, None);\n";