//===- AsmMatcherEmitter.cpp - Generate an assembly matcher ---------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This tablegen backend emits a target specifier matcher for converting parsed // assembly operands in the MCInst structures. // // The input to the target specific matcher is a list of literal tokens and // operands. The target specific parser should generally eliminate any syntax // which is not relevant for matching; for example, comma tokens should have // already been consumed and eliminated by the parser. Most instructions will // end up with a single literal token (the instruction name) and some number of // operands. // // Some example inputs, for X86: // 'addl' (immediate ...) (register ...) // 'add' (immediate ...) (memory ...) // 'call' '*' %epc // // The assembly matcher is responsible for converting this input into a precise // machine instruction (i.e., an instruction with a well defined encoding). This // mapping has several properties which complicate matching: // // - It may be ambiguous; many architectures can legally encode particular // variants of an instruction in different ways (for example, using a smaller // encoding for small immediates). Such ambiguities should never be // arbitrarily resolved by the assembler, the assembler is always responsible // for choosing the "best" available instruction. // // - It may depend on the subtarget or the assembler context. Instructions // which are invalid for the current mode, but otherwise unambiguous (e.g., // an SSE instruction in a file being assembled for i486) should be accepted // and rejected by the assembler front end. However, if the proper encoding // for an instruction is dependent on the assembler context then the matcher // is responsible for selecting the correct machine instruction for the // current mode. // // The core matching algorithm attempts to exploit the regularity in most // instruction sets to quickly determine the set of possibly matching // instructions, and the simplify the generated code. Additionally, this helps // to ensure that the ambiguities are intentionally resolved by the user. // // The matching is divided into two distinct phases: // // 1. Classification: Each operand is mapped to the unique set which (a) // contains it, and (b) is the largest such subset for which a single // instruction could match all members. // // For register classes, we can generate these subgroups automatically. For // arbitrary operands, we expect the user to define the classes and their // relations to one another (for example, 8-bit signed immediates as a // subset of 32-bit immediates). // // By partitioning the operands in this way, we guarantee that for any // tuple of classes, any single instruction must match either all or none // of the sets of operands which could classify to that tuple. // // In addition, the subset relation amongst classes induces a partial order // on such tuples, which we use to resolve ambiguities. // // FIXME: What do we do if a crazy case shows up where this is the wrong // resolution? // // 2. The input can now be treated as a tuple of classes (static tokens are // simple singleton sets). Each such tuple should generally map to a single // instruction (we currently ignore cases where this isn't true, whee!!!), // which we can emit a simple matcher for. // //===----------------------------------------------------------------------===// #include "AsmMatcherEmitter.h" #include "CodeGenTarget.h" #include "Record.h" #include "llvm/ADT/OwningPtr.h" #include "llvm/ADT/SmallVector.h" #include "llvm/ADT/STLExtras.h" #include "llvm/ADT/StringExtras.h" #include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include <list> #include <map> #include <set> using namespace llvm; static cl::opt<std::string> MatchPrefix("match-prefix", cl::init(""), cl::desc("Only match instructions with the given prefix")); /// FlattenVariants - Flatten an .td file assembly string by selecting the /// variant at index \arg N. static std::string FlattenVariants(const std::string &AsmString, unsigned N) { StringRef Cur = AsmString; std::string Res = ""; for (;;) { // Find the start of the next variant string. size_t VariantsStart = 0; for (size_t e = Cur.size(); VariantsStart != e; ++VariantsStart) if (Cur[VariantsStart] == '{' && (VariantsStart == 0 || (Cur[VariantsStart-1] != '$' && Cur[VariantsStart-1] != '\\'))) break; // Add the prefix to the result. Res += Cur.slice(0, VariantsStart); if (VariantsStart == Cur.size()) break; ++VariantsStart; // Skip the '{'. // Scan to the end of the variants string. size_t VariantsEnd = VariantsStart; unsigned NestedBraces = 1; for (size_t e = Cur.size(); VariantsEnd != e; ++VariantsEnd) { if (Cur[VariantsEnd] == '}' && Cur[VariantsEnd-1] != '\\') { if (--NestedBraces == 0) break; } else if (Cur[VariantsEnd] == '{') ++NestedBraces; } // Select the Nth variant (or empty). StringRef Selection = Cur.slice(VariantsStart, VariantsEnd); for (unsigned i = 0; i != N; ++i) Selection = Selection.split('|').second; Res += Selection.split('|').first; assert(VariantsEnd != Cur.size() && "Unterminated variants in assembly string!"); Cur = Cur.substr(VariantsEnd + 1); } return Res; } /// TokenizeAsmString - Tokenize a simplified assembly string. static void TokenizeAsmString(const StringRef &AsmString, SmallVectorImpl<StringRef> &Tokens) { unsigned Prev = 0; bool InTok = true; for (unsigned i = 0, e = AsmString.size(); i != e; ++i) { switch (AsmString[i]) { case '[': case ']': case '*': case '!': case ' ': case '\t': case ',': if (InTok) { Tokens.push_back(AsmString.slice(Prev, i)); InTok = false; } if (!isspace(AsmString[i]) && AsmString[i] != ',') Tokens.push_back(AsmString.substr(i, 1)); Prev = i + 1; break; case '\\': if (InTok) { Tokens.push_back(AsmString.slice(Prev, i)); InTok = false; } ++i; assert(i != AsmString.size() && "Invalid quoted character"); Tokens.push_back(AsmString.substr(i, 1)); Prev = i + 1; break; case '$': { // If this isn't "${", treat like a normal token. if (i + 1 == AsmString.size() || AsmString[i + 1] != '{') { if (InTok) { Tokens.push_back(AsmString.slice(Prev, i)); InTok = false; } Prev = i; break; } if (InTok) { Tokens.push_back(AsmString.slice(Prev, i)); InTok = false; } StringRef::iterator End = std::find(AsmString.begin() + i, AsmString.end(), '}'); assert(End != AsmString.end() && "Missing brace in operand reference!"); size_t EndPos = End - AsmString.begin(); Tokens.push_back(AsmString.slice(i, EndPos+1)); Prev = EndPos + 1; i = EndPos; break; } default: InTok = true; } } if (InTok && Prev != AsmString.size()) Tokens.push_back(AsmString.substr(Prev)); } static bool IsAssemblerInstruction(const StringRef &Name, const CodeGenInstruction &CGI, const SmallVectorImpl<StringRef> &Tokens) { // Ignore "codegen only" instructions. if (CGI.TheDef->getValueAsBit("isCodeGenOnly")) return false; // Ignore pseudo ops. // // FIXME: This is a hack; can we convert these instructions to set the // "codegen only" bit instead? if (const RecordVal *Form = CGI.TheDef->getValue("Form")) if (Form->getValue()->getAsString() == "Pseudo") return false; // Ignore "Int_*" and "*_Int" instructions, which are internal aliases. // // FIXME: This is a total hack. if (StringRef(Name).startswith("Int_") || StringRef(Name).endswith("_Int")) return false; // Ignore instructions with no .s string. // // FIXME: What are these? if (CGI.AsmString.empty()) return false; // FIXME: Hack; ignore any instructions with a newline in them. if (std::find(CGI.AsmString.begin(), CGI.AsmString.end(), '\n') != CGI.AsmString.end()) return false; // Ignore instructions with attributes, these are always fake instructions for // simplifying codegen. // // FIXME: Is this true? // // Also, check for instructions which reference the operand multiple times; // this implies a constraint we would not honor. std::set<std::string> OperandNames; for (unsigned i = 1, e = Tokens.size(); i < e; ++i) { if (Tokens[i][0] == '$' && std::find(Tokens[i].begin(), Tokens[i].end(), ':') != Tokens[i].end()) { DEBUG({ errs() << "warning: '" << Name << "': " << "ignoring instruction; operand with attribute '" << Tokens[i] << "'\n"; }); return false; } if (Tokens[i][0] == '$' && !OperandNames.insert(Tokens[i]).second) { std::string Err = "'" + Name.str() + "': " + "invalid assembler instruction; tied operand '" + Tokens[i].str() + "'"; throw TGError(CGI.TheDef->getLoc(), Err); } } return true; } namespace { /// ClassInfo - Helper class for storing the information about a particular /// class of operands which can be matched. struct ClassInfo { enum ClassInfoKind { /// Invalid kind, for use as a sentinel value. Invalid = 0, /// The class for a particular token. Token, /// The (first) register class, subsequent register classes are /// RegisterClass0+1, and so on. RegisterClass0, /// The (first) user defined class, subsequent user defined classes are /// UserClass0+1, and so on. UserClass0 = 1<<16 }; /// Kind - The class kind, which is either a predefined kind, or (UserClass0 + /// N) for the Nth user defined class. unsigned Kind; /// SuperClasses - The super classes of this class. Note that for simplicities /// sake user operands only record their immediate super class, while register /// operands include all superclasses. std::vector<ClassInfo*> SuperClasses; /// Name - The full class name, suitable for use in an enum. std::string Name; /// ClassName - The unadorned generic name for this class (e.g., Token). std::string ClassName; /// ValueName - The name of the value this class represents; for a token this /// is the literal token string, for an operand it is the TableGen class (or /// empty if this is a derived class). std::string ValueName; /// PredicateMethod - The name of the operand method to test whether the /// operand matches this class; this is not valid for Token or register kinds. std::string PredicateMethod; /// RenderMethod - The name of the operand method to add this operand to an /// MCInst; this is not valid for Token or register kinds. std::string RenderMethod; /// For register classes, the records for all the registers in this class. std::set<Record*> Registers; public: /// isRegisterClass() - Check if this is a register class. bool isRegisterClass() const { return Kind >= RegisterClass0 && Kind < UserClass0; } /// isUserClass() - Check if this is a user defined class. bool isUserClass() const { return Kind >= UserClass0; } /// isRelatedTo - Check whether this class is "related" to \arg RHS. Classes /// are related if they are in the same class hierarchy. bool isRelatedTo(const ClassInfo &RHS) const { // Tokens are only related to tokens. if (Kind == Token || RHS.Kind == Token) return Kind == Token && RHS.Kind == Token; // Registers classes are only related to registers classes, and only if // their intersection is non-empty. if (isRegisterClass() || RHS.isRegisterClass()) { if (!isRegisterClass() || !RHS.isRegisterClass()) return false; std::set<Record*> Tmp; std::insert_iterator< std::set<Record*> > II(Tmp, Tmp.begin()); std::set_intersection(Registers.begin(), Registers.end(), RHS.Registers.begin(), RHS.Registers.end(), II); return !Tmp.empty(); } // Otherwise we have two users operands; they are related if they are in the // same class hierarchy. // // FIXME: This is an oversimplification, they should only be related if they // intersect, however we don't have that information. assert(isUserClass() && RHS.isUserClass() && "Unexpected class!"); const ClassInfo *Root = this; while (!Root->SuperClasses.empty()) Root = Root->SuperClasses.front(); const ClassInfo *RHSRoot = &RHS; while (!RHSRoot->SuperClasses.empty()) RHSRoot = RHSRoot->SuperClasses.front(); return Root == RHSRoot; } /// isSubsetOf - Test whether this class is a subset of \arg RHS; bool isSubsetOf(const ClassInfo &RHS) const { // This is a subset of RHS if it is the same class... if (this == &RHS) return true; // ... or if any of its super classes are a subset of RHS. for (std::vector<ClassInfo*>::const_iterator it = SuperClasses.begin(), ie = SuperClasses.end(); it != ie; ++it) if ((*it)->isSubsetOf(RHS)) return true; return false; } /// operator< - Compare two classes. bool operator<(const ClassInfo &RHS) const { // Unrelated classes can be ordered by kind. if (!isRelatedTo(RHS)) return Kind < RHS.Kind; switch (Kind) { case Invalid: assert(0 && "Invalid kind!"); case Token: // Tokens are comparable by value. // // FIXME: Compare by enum value. return ValueName < RHS.ValueName; default: // This class preceeds the RHS if it is a proper subset of the RHS. return this != &RHS && isSubsetOf(RHS); } } }; /// InstructionInfo - Helper class for storing the necessary information for an /// instruction which is capable of being matched. struct InstructionInfo { struct Operand { /// The unique class instance this operand should match. ClassInfo *Class; /// The original operand this corresponds to, if any. const CodeGenInstruction::OperandInfo *OperandInfo; }; /// InstrName - The target name for this instruction. std::string InstrName; /// Instr - The instruction this matches. const CodeGenInstruction *Instr; /// AsmString - The assembly string for this instruction (with variants /// removed). std::string AsmString; /// Tokens - The tokenized assembly pattern that this instruction matches. SmallVector<StringRef, 4> Tokens; /// Operands - The operands that this instruction matches. SmallVector<Operand, 4> Operands; /// ConversionFnKind - The enum value which is passed to the generated /// ConvertToMCInst to convert parsed operands into an MCInst for this /// function. std::string ConversionFnKind; /// operator< - Compare two instructions. bool operator<(const InstructionInfo &RHS) const { if (Operands.size() != RHS.Operands.size()) return Operands.size() < RHS.Operands.size(); // Compare lexicographically by operand. The matcher validates that other // orderings wouldn't be ambiguous using \see CouldMatchAmiguouslyWith(). for (unsigned i = 0, e = Operands.size(); i != e; ++i) { if (*Operands[i].Class < *RHS.Operands[i].Class) return true; if (*RHS.Operands[i].Class < *Operands[i].Class) return false; } return false; } /// CouldMatchAmiguouslyWith - Check whether this instruction could /// ambiguously match the same set of operands as \arg RHS (without being a /// strictly superior match). bool CouldMatchAmiguouslyWith(const InstructionInfo &RHS) { // The number of operands is unambiguous. if (Operands.size() != RHS.Operands.size()) return false; // Tokens and operand kinds are unambiguous (assuming a correct target // specific parser). for (unsigned i = 0, e = Operands.size(); i != e; ++i) if (Operands[i].Class->Kind != RHS.Operands[i].Class->Kind || Operands[i].Class->Kind == ClassInfo::Token) if (*Operands[i].Class < *RHS.Operands[i].Class || *RHS.Operands[i].Class < *Operands[i].Class) return false; // Otherwise, this operand could commute if all operands are equivalent, or // there is a pair of operands that compare less than and a pair that // compare greater than. bool HasLT = false, HasGT = false; for (unsigned i = 0, e = Operands.size(); i != e; ++i) { if (*Operands[i].Class < *RHS.Operands[i].Class) HasLT = true; if (*RHS.Operands[i].Class < *Operands[i].Class) HasGT = true; } return !(HasLT ^ HasGT); } public: void dump(); }; class AsmMatcherInfo { public: /// The tablegen AsmParser record. Record *AsmParser; /// The AsmParser "CommentDelimiter" value. std::string CommentDelimiter; /// The AsmParser "RegisterPrefix" value. std::string RegisterPrefix; /// The classes which are needed for matching. std::vector<ClassInfo*> Classes; /// The information on the instruction to match. std::vector<InstructionInfo*> Instructions; /// Map of Register records to their class information. std::map<Record*, ClassInfo*> RegisterClasses; private: /// Map of token to class information which has already been constructed. std::map<std::string, ClassInfo*> TokenClasses; /// Map of RegisterClass records to their class information. std::map<Record*, ClassInfo*> RegisterClassClasses; /// Map of AsmOperandClass records to their class information. std::map<Record*, ClassInfo*> AsmOperandClasses; private: /// getTokenClass - Lookup or create the class for the given token. ClassInfo *getTokenClass(const StringRef &Token); /// getOperandClass - Lookup or create the class for the given operand. ClassInfo *getOperandClass(const StringRef &Token, const CodeGenInstruction::OperandInfo &OI); /// BuildRegisterClasses - Build the ClassInfo* instances for register /// classes. void BuildRegisterClasses(CodeGenTarget &Target, std::set<std::string> &SingletonRegisterNames); /// BuildOperandClasses - Build the ClassInfo* instances for user defined /// operand classes. void BuildOperandClasses(CodeGenTarget &Target); public: AsmMatcherInfo(Record *_AsmParser); /// BuildInfo - Construct the various tables used during matching. void BuildInfo(CodeGenTarget &Target); }; } void InstructionInfo::dump() { errs() << InstrName << " -- " << "flattened:\"" << AsmString << '\"' << ", tokens:["; for (unsigned i = 0, e = Tokens.size(); i != e; ++i) { errs() << Tokens[i]; if (i + 1 != e) errs() << ", "; } errs() << "]\n"; for (unsigned i = 0, e = Operands.size(); i != e; ++i) { Operand &Op = Operands[i]; errs() << " op[" << i << "] = " << Op.Class->ClassName << " - "; if (Op.Class->Kind == ClassInfo::Token) { errs() << '\"' << Tokens[i] << "\"\n"; continue; } if (!Op.OperandInfo) { errs() << "(singleton register)\n"; continue; } const CodeGenInstruction::OperandInfo &OI = *Op.OperandInfo; errs() << OI.Name << " " << OI.Rec->getName() << " (" << OI.MIOperandNo << ", " << OI.MINumOperands << ")\n"; } } static std::string getEnumNameForToken(const StringRef &Str) { std::string Res; for (StringRef::iterator it = Str.begin(), ie = Str.end(); it != ie; ++it) { switch (*it) { case '*': Res += "_STAR_"; break; case '%': Res += "_PCT_"; break; case ':': Res += "_COLON_"; break; default: if (isalnum(*it)) { Res += *it; } else { Res += "_" + utostr((unsigned) *it) + "_"; } } } return Res; } /// getRegisterRecord - Get the register record for \arg name, or 0. static Record *getRegisterRecord(CodeGenTarget &Target, const StringRef &Name) { for (unsigned i = 0, e = Target.getRegisters().size(); i != e; ++i) { const CodeGenRegister &Reg = Target.getRegisters()[i]; if (Name == Reg.TheDef->getValueAsString("AsmName")) return Reg.TheDef; } return 0; } ClassInfo *AsmMatcherInfo::getTokenClass(const StringRef &Token) { ClassInfo *&Entry = TokenClasses[Token]; if (!Entry) { Entry = new ClassInfo(); Entry->Kind = ClassInfo::Token; Entry->ClassName = "Token"; Entry->Name = "MCK_" + getEnumNameForToken(Token); Entry->ValueName = Token; Entry->PredicateMethod = "<invalid>"; Entry->RenderMethod = "<invalid>"; Classes.push_back(Entry); } return Entry; } ClassInfo * AsmMatcherInfo::getOperandClass(const StringRef &Token, const CodeGenInstruction::OperandInfo &OI) { if (OI.Rec->isSubClassOf("RegisterClass")) { ClassInfo *CI = RegisterClassClasses[OI.Rec]; if (!CI) { PrintError(OI.Rec->getLoc(), "register class has no class info!"); throw std::string("ERROR: Missing register class!"); } return CI; } assert(OI.Rec->isSubClassOf("Operand") && "Unexpected operand!"); Record *MatchClass = OI.Rec->getValueAsDef("ParserMatchClass"); ClassInfo *CI = AsmOperandClasses[MatchClass]; if (!CI) { PrintError(OI.Rec->getLoc(), "operand has no match class!"); throw std::string("ERROR: Missing match class!"); } return CI; } void AsmMatcherInfo::BuildRegisterClasses(CodeGenTarget &Target, std::set<std::string> &SingletonRegisterNames) { std::vector<CodeGenRegisterClass> RegisterClasses; std::vector<CodeGenRegister> Registers; RegisterClasses = Target.getRegisterClasses(); Registers = Target.getRegisters(); // The register sets used for matching. std::set< std::set<Record*> > RegisterSets; // Gather the defined sets. for (std::vector<CodeGenRegisterClass>::iterator it = RegisterClasses.begin(), ie = RegisterClasses.end(); it != ie; ++it) RegisterSets.insert(std::set<Record*>(it->Elements.begin(), it->Elements.end())); // Add any required singleton sets. for (std::set<std::string>::iterator it = SingletonRegisterNames.begin(), ie = SingletonRegisterNames.end(); it != ie; ++it) if (Record *Rec = getRegisterRecord(Target, *it)) RegisterSets.insert(std::set<Record*>(&Rec, &Rec + 1)); // Introduce derived sets where necessary (when a register does not determine // a unique register set class), and build the mapping of registers to the set // they should classify to. std::map<Record*, std::set<Record*> > RegisterMap; for (std::vector<CodeGenRegister>::iterator it = Registers.begin(), ie = Registers.end(); it != ie; ++it) { CodeGenRegister &CGR = *it; // Compute the intersection of all sets containing this register. std::set<Record*> ContainingSet; for (std::set< std::set<Record*> >::iterator it = RegisterSets.begin(), ie = RegisterSets.end(); it != ie; ++it) { if (!it->count(CGR.TheDef)) continue; if (ContainingSet.empty()) { ContainingSet = *it; } else { std::set<Record*> Tmp; std::swap(Tmp, ContainingSet); std::insert_iterator< std::set<Record*> > II(ContainingSet, ContainingSet.begin()); std::set_intersection(Tmp.begin(), Tmp.end(), it->begin(), it->end(), II); } } if (!ContainingSet.empty()) { RegisterSets.insert(ContainingSet); RegisterMap.insert(std::make_pair(CGR.TheDef, ContainingSet)); } } // Construct the register classes. std::map<std::set<Record*>, ClassInfo*> RegisterSetClasses; unsigned Index = 0; for (std::set< std::set<Record*> >::iterator it = RegisterSets.begin(), ie = RegisterSets.end(); it != ie; ++it, ++Index) { ClassInfo *CI = new ClassInfo(); CI->Kind = ClassInfo::RegisterClass0 + Index; CI->ClassName = "Reg" + utostr(Index); CI->Name = "MCK_Reg" + utostr(Index); CI->ValueName = ""; CI->PredicateMethod = ""; // unused CI->RenderMethod = "addRegOperands"; CI->Registers = *it; Classes.push_back(CI); RegisterSetClasses.insert(std::make_pair(*it, CI)); } // Find the superclasses; we could compute only the subgroup lattice edges, // but there isn't really a point. for (std::set< std::set<Record*> >::iterator it = RegisterSets.begin(), ie = RegisterSets.end(); it != ie; ++it) { ClassInfo *CI = RegisterSetClasses[*it]; for (std::set< std::set<Record*> >::iterator it2 = RegisterSets.begin(), ie2 = RegisterSets.end(); it2 != ie2; ++it2) if (*it != *it2 && std::includes(it2->begin(), it2->end(), it->begin(), it->end())) CI->SuperClasses.push_back(RegisterSetClasses[*it2]); } // Name the register classes which correspond to a user defined RegisterClass. for (std::vector<CodeGenRegisterClass>::iterator it = RegisterClasses.begin(), ie = RegisterClasses.end(); it != ie; ++it) { ClassInfo *CI = RegisterSetClasses[std::set<Record*>(it->Elements.begin(), it->Elements.end())]; if (CI->ValueName.empty()) { CI->ClassName = it->getName(); CI->Name = "MCK_" + it->getName(); CI->ValueName = it->getName(); } else CI->ValueName = CI->ValueName + "," + it->getName(); RegisterClassClasses.insert(std::make_pair(it->TheDef, CI)); } // Populate the map for individual registers. for (std::map<Record*, std::set<Record*> >::iterator it = RegisterMap.begin(), ie = RegisterMap.end(); it != ie; ++it) this->RegisterClasses[it->first] = RegisterSetClasses[it->second]; // Name the register classes which correspond to singleton registers. for (std::set<std::string>::iterator it = SingletonRegisterNames.begin(), ie = SingletonRegisterNames.end(); it != ie; ++it) { if (Record *Rec = getRegisterRecord(Target, *it)) { ClassInfo *CI = this->RegisterClasses[Rec]; assert(CI && "Missing singleton register class info!"); if (CI->ValueName.empty()) { CI->ClassName = Rec->getName(); CI->Name = "MCK_" + Rec->getName(); CI->ValueName = Rec->getName(); } else CI->ValueName = CI->ValueName + "," + Rec->getName(); } } } void AsmMatcherInfo::BuildOperandClasses(CodeGenTarget &Target) { std::vector<Record*> AsmOperands; AsmOperands = Records.getAllDerivedDefinitions("AsmOperandClass"); unsigned Index = 0; for (std::vector<Record*>::iterator it = AsmOperands.begin(), ie = AsmOperands.end(); it != ie; ++it, ++Index) { ClassInfo *CI = new ClassInfo(); CI->Kind = ClassInfo::UserClass0 + Index; Init *Super = (*it)->getValueInit("SuperClass"); if (DefInit *DI = dynamic_cast<DefInit*>(Super)) { ClassInfo *SC = AsmOperandClasses[DI->getDef()]; if (!SC) PrintError((*it)->getLoc(), "Invalid super class reference!"); else CI->SuperClasses.push_back(SC); } else { assert(dynamic_cast<UnsetInit*>(Super) && "Unexpected SuperClass field!"); } CI->ClassName = (*it)->getValueAsString("Name"); CI->Name = "MCK_" + CI->ClassName; CI->ValueName = (*it)->getName(); // Get or construct the predicate method name. Init *PMName = (*it)->getValueInit("PredicateMethod"); if (StringInit *SI = dynamic_cast<StringInit*>(PMName)) { CI->PredicateMethod = SI->getValue(); } else { assert(dynamic_cast<UnsetInit*>(PMName) && "Unexpected PredicateMethod field!"); CI->PredicateMethod = "is" + CI->ClassName; } // Get or construct the render method name. Init *RMName = (*it)->getValueInit("RenderMethod"); if (StringInit *SI = dynamic_cast<StringInit*>(RMName)) { CI->RenderMethod = SI->getValue(); } else { assert(dynamic_cast<UnsetInit*>(RMName) && "Unexpected RenderMethod field!"); CI->RenderMethod = "add" + CI->ClassName + "Operands"; } AsmOperandClasses[*it] = CI; Classes.push_back(CI); } } AsmMatcherInfo::AsmMatcherInfo(Record *_AsmParser) : AsmParser(_AsmParser), CommentDelimiter(AsmParser->getValueAsString("CommentDelimiter")), RegisterPrefix(AsmParser->getValueAsString("RegisterPrefix")) { } void AsmMatcherInfo::BuildInfo(CodeGenTarget &Target) { // Parse the instructions; we need to do this first so that we can gather the // singleton register classes. std::set<std::string> SingletonRegisterNames; for (std::map<std::string, CodeGenInstruction>::const_iterator it = Target.getInstructions().begin(), ie = Target.getInstructions().end(); it != ie; ++it) { const CodeGenInstruction &CGI = it->second; if (!StringRef(it->first).startswith(MatchPrefix)) continue; OwningPtr<InstructionInfo> II(new InstructionInfo); II->InstrName = it->first; II->Instr = &it->second; II->AsmString = FlattenVariants(CGI.AsmString, 0); // Remove comments from the asm string. if (!CommentDelimiter.empty()) { size_t Idx = StringRef(II->AsmString).find(CommentDelimiter); if (Idx != StringRef::npos) II->AsmString = II->AsmString.substr(0, Idx); } TokenizeAsmString(II->AsmString, II->Tokens); // Ignore instructions which shouldn't be matched. if (!IsAssemblerInstruction(it->first, CGI, II->Tokens)) continue; // Collect singleton registers, if used. if (!RegisterPrefix.empty()) { for (unsigned i = 0, e = II->Tokens.size(); i != e; ++i) { if (II->Tokens[i].startswith(RegisterPrefix)) { StringRef RegName = II->Tokens[i].substr(RegisterPrefix.size()); Record *Rec = getRegisterRecord(Target, RegName); if (!Rec) { std::string Err = "unable to find register for '" + RegName.str() + "' (which matches register prefix)"; throw TGError(CGI.TheDef->getLoc(), Err); } SingletonRegisterNames.insert(RegName); } } } Instructions.push_back(II.take()); } // Build info for the register classes. BuildRegisterClasses(Target, SingletonRegisterNames); // Build info for the user defined assembly operand classes. BuildOperandClasses(Target); // Build the instruction information. for (std::vector<InstructionInfo*>::iterator it = Instructions.begin(), ie = Instructions.end(); it != ie; ++it) { InstructionInfo *II = *it; for (unsigned i = 0, e = II->Tokens.size(); i != e; ++i) { StringRef Token = II->Tokens[i]; // Check for singleton registers. if (!RegisterPrefix.empty() && Token.startswith(RegisterPrefix)) { StringRef RegName = II->Tokens[i].substr(RegisterPrefix.size()); InstructionInfo::Operand Op; Op.Class = RegisterClasses[getRegisterRecord(Target, RegName)]; Op.OperandInfo = 0; assert(Op.Class && Op.Class->Registers.size() == 1 && "Unexpected class for singleton register"); II->Operands.push_back(Op); continue; } // Check for simple tokens. if (Token[0] != '$') { InstructionInfo::Operand Op; Op.Class = getTokenClass(Token); Op.OperandInfo = 0; II->Operands.push_back(Op); continue; } // Otherwise this is an operand reference. StringRef OperandName; if (Token[1] == '{') OperandName = Token.substr(2, Token.size() - 3); else OperandName = Token.substr(1); // Map this token to an operand. FIXME: Move elsewhere. unsigned Idx; try { Idx = II->Instr->getOperandNamed(OperandName); } catch(...) { throw std::string("error: unable to find operand: '" + OperandName.str() + "'"); } const CodeGenInstruction::OperandInfo &OI = II->Instr->OperandList[Idx]; InstructionInfo::Operand Op; Op.Class = getOperandClass(Token, OI); Op.OperandInfo = &OI; II->Operands.push_back(Op); } } // Reorder classes so that classes preceed super classes. std::sort(Classes.begin(), Classes.end(), less_ptr<ClassInfo>()); } static void EmitConvertToMCInst(CodeGenTarget &Target, std::vector<InstructionInfo*> &Infos, raw_ostream &OS) { // Write the convert function to a separate stream, so we can drop it after // the enum. std::string ConvertFnBody; raw_string_ostream CvtOS(ConvertFnBody); // Function we have already generated. std::set<std::string> GeneratedFns; // Start the unified conversion function. CvtOS << "static bool ConvertToMCInst(ConversionKind Kind, MCInst &Inst, " << "unsigned Opcode,\n" << " SmallVectorImpl<" << Target.getName() << "Operand> &Operands) {\n"; CvtOS << " Inst.setOpcode(Opcode);\n"; CvtOS << " switch (Kind) {\n"; CvtOS << " default:\n"; // Start the enum, which we will generate inline. OS << "// Unified function for converting operants to MCInst instances.\n\n"; OS << "enum ConversionKind {\n"; for (std::vector<InstructionInfo*>::const_iterator it = Infos.begin(), ie = Infos.end(); it != ie; ++it) { InstructionInfo &II = **it; // Order the (class) operands by the order to convert them into an MCInst. SmallVector<std::pair<unsigned, unsigned>, 4> MIOperandList; for (unsigned i = 0, e = II.Operands.size(); i != e; ++i) { InstructionInfo::Operand &Op = II.Operands[i]; if (Op.OperandInfo) MIOperandList.push_back(std::make_pair(Op.OperandInfo->MIOperandNo, i)); } std::sort(MIOperandList.begin(), MIOperandList.end()); // Compute the total number of operands. unsigned NumMIOperands = 0; for (unsigned i = 0, e = II.Instr->OperandList.size(); i != e; ++i) { const CodeGenInstruction::OperandInfo &OI = II.Instr->OperandList[i]; NumMIOperands = std::max(NumMIOperands, OI.MIOperandNo + OI.MINumOperands); } // Build the conversion function signature. std::string Signature = "Convert"; unsigned CurIndex = 0; for (unsigned i = 0, e = MIOperandList.size(); i != e; ++i) { InstructionInfo::Operand &Op = II.Operands[MIOperandList[i].second]; assert(CurIndex <= Op.OperandInfo->MIOperandNo && "Duplicate match for instruction operand!"); Signature += "_"; // Skip operands which weren't matched by anything, this occurs when the // .td file encodes "implicit" operands as explicit ones. // // FIXME: This should be removed from the MCInst structure. for (; CurIndex != Op.OperandInfo->MIOperandNo; ++CurIndex) Signature += "Imp"; // Registers are always converted the same, don't duplicate the conversion // function based on them. // // FIXME: We could generalize this based on the render method, if it // mattered. if (Op.Class->isRegisterClass()) Signature += "Reg"; else Signature += Op.Class->ClassName; Signature += utostr(Op.OperandInfo->MINumOperands); Signature += "_" + utostr(MIOperandList[i].second); CurIndex += Op.OperandInfo->MINumOperands; } // Add any trailing implicit operands. for (; CurIndex != NumMIOperands; ++CurIndex) Signature += "Imp"; II.ConversionFnKind = Signature; // Check if we have already generated this signature. if (!GeneratedFns.insert(Signature).second) continue; // If not, emit it now. // Add to the enum list. OS << " " << Signature << ",\n"; // And to the convert function. CvtOS << " case " << Signature << ":\n"; CurIndex = 0; for (unsigned i = 0, e = MIOperandList.size(); i != e; ++i) { InstructionInfo::Operand &Op = II.Operands[MIOperandList[i].second]; // Add the implicit operands. for (; CurIndex != Op.OperandInfo->MIOperandNo; ++CurIndex) CvtOS << " Inst.addOperand(MCOperand::CreateReg(0));\n"; CvtOS << " Operands[" << MIOperandList[i].second << "]." << Op.Class->RenderMethod << "(Inst, " << Op.OperandInfo->MINumOperands << ");\n"; CurIndex += Op.OperandInfo->MINumOperands; } // And add trailing implicit operands. for (; CurIndex != NumMIOperands; ++CurIndex) CvtOS << " Inst.addOperand(MCOperand::CreateReg(0));\n"; CvtOS << " break;\n"; } // Finish the convert function. CvtOS << " }\n"; CvtOS << " return false;\n"; CvtOS << "}\n\n"; // Finish the enum, and drop the convert function after it. OS << " NumConversionVariants\n"; OS << "};\n\n"; OS << CvtOS.str(); } /// EmitMatchClassEnumeration - Emit the enumeration for match class kinds. static void EmitMatchClassEnumeration(CodeGenTarget &Target, std::vector<ClassInfo*> &Infos, raw_ostream &OS) { OS << "namespace {\n\n"; OS << "/// MatchClassKind - The kinds of classes which participate in\n" << "/// instruction matching.\n"; OS << "enum MatchClassKind {\n"; OS << " InvalidMatchClass = 0,\n"; for (std::vector<ClassInfo*>::iterator it = Infos.begin(), ie = Infos.end(); it != ie; ++it) { ClassInfo &CI = **it; OS << " " << CI.Name << ", // "; if (CI.Kind == ClassInfo::Token) { OS << "'" << CI.ValueName << "'\n"; } else if (CI.isRegisterClass()) { if (!CI.ValueName.empty()) OS << "register class '" << CI.ValueName << "'\n"; else OS << "derived register class\n"; } else { OS << "user defined class '" << CI.ValueName << "'\n"; } } OS << " NumMatchClassKinds\n"; OS << "};\n\n"; OS << "}\n\n"; } /// EmitClassifyOperand - Emit the function to classify an operand. static void EmitClassifyOperand(CodeGenTarget &Target, AsmMatcherInfo &Info, raw_ostream &OS) { OS << "static MatchClassKind ClassifyOperand(" << Target.getName() << "Operand &Operand) {\n"; // Classify tokens. OS << " if (Operand.isToken())\n"; OS << " return MatchTokenString(Operand.getToken());\n\n"; // Classify registers. // // FIXME: Don't hardcode isReg, getReg. OS << " if (Operand.isReg()) {\n"; OS << " switch (Operand.getReg()) {\n"; OS << " default: return InvalidMatchClass;\n"; for (std::map<Record*, ClassInfo*>::iterator it = Info.RegisterClasses.begin(), ie = Info.RegisterClasses.end(); it != ie; ++it) OS << " case " << Target.getName() << "::" << it->first->getName() << ": return " << it->second->Name << ";\n"; OS << " }\n"; OS << " }\n\n"; // Classify user defined operands. for (std::vector<ClassInfo*>::iterator it = Info.Classes.begin(), ie = Info.Classes.end(); it != ie; ++it) { ClassInfo &CI = **it; if (!CI.isUserClass()) continue; OS << " // '" << CI.ClassName << "' class"; if (!CI.SuperClasses.empty()) { OS << ", subclass of "; for (unsigned i = 0, e = CI.SuperClasses.size(); i != e; ++i) { if (i) OS << ", "; OS << "'" << CI.SuperClasses[i]->ClassName << "'"; assert(CI < *CI.SuperClasses[i] && "Invalid class relation!"); } } OS << "\n"; OS << " if (Operand." << CI.PredicateMethod << "()) {\n"; // Validate subclass relationships. if (!CI.SuperClasses.empty()) { for (unsigned i = 0, e = CI.SuperClasses.size(); i != e; ++i) OS << " assert(Operand." << CI.SuperClasses[i]->PredicateMethod << "() && \"Invalid class relationship!\");\n"; } OS << " return " << CI.Name << ";\n"; OS << " }\n\n"; } OS << " return InvalidMatchClass;\n"; OS << "}\n\n"; } /// EmitIsSubclass - Emit the subclass predicate function. static void EmitIsSubclass(CodeGenTarget &Target, std::vector<ClassInfo*> &Infos, raw_ostream &OS) { OS << "/// IsSubclass - Compute whether \\arg A is a subclass of \\arg B.\n"; OS << "static bool IsSubclass(MatchClassKind A, MatchClassKind B) {\n"; OS << " if (A == B)\n"; OS << " return true;\n\n"; OS << " switch (A) {\n"; OS << " default:\n"; OS << " return false;\n"; for (std::vector<ClassInfo*>::iterator it = Infos.begin(), ie = Infos.end(); it != ie; ++it) { ClassInfo &A = **it; if (A.Kind != ClassInfo::Token) { std::vector<StringRef> SuperClasses; for (std::vector<ClassInfo*>::iterator it = Infos.begin(), ie = Infos.end(); it != ie; ++it) { ClassInfo &B = **it; if (&A != &B && A.isSubsetOf(B)) SuperClasses.push_back(B.Name); } if (SuperClasses.empty()) continue; OS << "\n case " << A.Name << ":\n"; if (SuperClasses.size() == 1) { OS << " return B == " << SuperClasses.back() << ";\n"; continue; } OS << " switch (B) {\n"; OS << " default: return false;\n"; for (unsigned i = 0, e = SuperClasses.size(); i != e; ++i) OS << " case " << SuperClasses[i] << ": return true;\n"; OS << " }\n"; } } OS << " }\n"; OS << "}\n\n"; } typedef std::pair<std::string, std::string> StringPair; /// FindFirstNonCommonLetter - Find the first character in the keys of the /// string pairs that is not shared across the whole set of strings. All /// strings are assumed to have the same length. static unsigned FindFirstNonCommonLetter(const std::vector<const StringPair*> &Matches) { assert(!Matches.empty()); for (unsigned i = 0, e = Matches[0]->first.size(); i != e; ++i) { // Check to see if letter i is the same across the set. char Letter = Matches[0]->first[i]; for (unsigned str = 0, e = Matches.size(); str != e; ++str) if (Matches[str]->first[i] != Letter) return i; } return Matches[0]->first.size(); } /// EmitStringMatcherForChar - Given a set of strings that are known to be the /// same length and whose characters leading up to CharNo are the same, emit /// code to verify that CharNo and later are the same. /// /// \return - True if control can leave the emitted code fragment. static bool EmitStringMatcherForChar(const std::string &StrVariableName, const std::vector<const StringPair*> &Matches, unsigned CharNo, unsigned IndentCount, raw_ostream &OS) { assert(!Matches.empty() && "Must have at least one string to match!"); std::string Indent(IndentCount*2+4, ' '); // If we have verified that the entire string matches, we're done: output the // matching code. if (CharNo == Matches[0]->first.size()) { assert(Matches.size() == 1 && "Had duplicate keys to match on"); // FIXME: If Matches[0].first has embeded \n, this will be bad. OS << Indent << Matches[0]->second << "\t // \"" << Matches[0]->first << "\"\n"; return false; } // Bucket the matches by the character we are comparing. std::map<char, std::vector<const StringPair*> > MatchesByLetter; for (unsigned i = 0, e = Matches.size(); i != e; ++i) MatchesByLetter[Matches[i]->first[CharNo]].push_back(Matches[i]); // If we have exactly one bucket to match, see how many characters are common // across the whole set and match all of them at once. if (MatchesByLetter.size() == 1) { unsigned FirstNonCommonLetter = FindFirstNonCommonLetter(Matches); unsigned NumChars = FirstNonCommonLetter-CharNo; // Emit code to break out if the prefix doesn't match. if (NumChars == 1) { // Do the comparison with if (Str[1] != 'f') // FIXME: Need to escape general characters. OS << Indent << "if (" << StrVariableName << "[" << CharNo << "] != '" << Matches[0]->first[CharNo] << "')\n"; OS << Indent << " break;\n"; } else { // Do the comparison with if (Str.substr(1,3) != "foo"). // FIXME: Need to escape general strings. OS << Indent << "if (" << StrVariableName << ".substr(" << CharNo << "," << NumChars << ") != \""; OS << Matches[0]->first.substr(CharNo, NumChars) << "\")\n"; OS << Indent << " break;\n"; } return EmitStringMatcherForChar(StrVariableName, Matches, FirstNonCommonLetter, IndentCount, OS); } // Otherwise, we have multiple possible things, emit a switch on the // character. OS << Indent << "switch (" << StrVariableName << "[" << CharNo << "]) {\n"; OS << Indent << "default: break;\n"; for (std::map<char, std::vector<const StringPair*> >::iterator LI = MatchesByLetter.begin(), E = MatchesByLetter.end(); LI != E; ++LI) { // TODO: escape hard stuff (like \n) if we ever care about it. OS << Indent << "case '" << LI->first << "':\t // " << LI->second.size() << " strings to match.\n"; if (EmitStringMatcherForChar(StrVariableName, LI->second, CharNo+1, IndentCount+1, OS)) OS << Indent << " break;\n"; } OS << Indent << "}\n"; return true; } /// EmitStringMatcher - Given a list of strings and code to execute when they /// match, output a simple switch tree to classify the input string. /// /// If a match is found, the code in Vals[i].second is executed; control must /// not exit this code fragment. If nothing matches, execution falls through. /// /// \param StrVariableName - The name of the variable to test. static void EmitStringMatcher(const std::string &StrVariableName, const std::vector<StringPair> &Matches, raw_ostream &OS) { // First level categorization: group strings by length. std::map<unsigned, std::vector<const StringPair*> > MatchesByLength; for (unsigned i = 0, e = Matches.size(); i != e; ++i) MatchesByLength[Matches[i].first.size()].push_back(&Matches[i]); // Output a switch statement on length and categorize the elements within each // bin. OS << " switch (" << StrVariableName << ".size()) {\n"; OS << " default: break;\n"; for (std::map<unsigned, std::vector<const StringPair*> >::iterator LI = MatchesByLength.begin(), E = MatchesByLength.end(); LI != E; ++LI) { OS << " case " << LI->first << ":\t // " << LI->second.size() << " strings to match.\n"; if (EmitStringMatcherForChar(StrVariableName, LI->second, 0, 0, OS)) OS << " break;\n"; } OS << " }\n"; } /// EmitMatchTokenString - Emit the function to match a token string to the /// appropriate match class value. static void EmitMatchTokenString(CodeGenTarget &Target, std::vector<ClassInfo*> &Infos, raw_ostream &OS) { // Construct the match list. std::vector<StringPair> Matches; for (std::vector<ClassInfo*>::iterator it = Infos.begin(), ie = Infos.end(); it != ie; ++it) { ClassInfo &CI = **it; if (CI.Kind == ClassInfo::Token) Matches.push_back(StringPair(CI.ValueName, "return " + CI.Name + ";")); } OS << "static MatchClassKind MatchTokenString(const StringRef &Name) {\n"; EmitStringMatcher("Name", Matches, OS); OS << " return InvalidMatchClass;\n"; OS << "}\n\n"; } /// EmitMatchRegisterName - Emit the function to match a string to the target /// specific register enum. static void EmitMatchRegisterName(CodeGenTarget &Target, Record *AsmParser, raw_ostream &OS) { // Construct the match list. std::vector<StringPair> Matches; for (unsigned i = 0, e = Target.getRegisters().size(); i != e; ++i) { const CodeGenRegister &Reg = Target.getRegisters()[i]; if (Reg.TheDef->getValueAsString("AsmName").empty()) continue; Matches.push_back(StringPair(Reg.TheDef->getValueAsString("AsmName"), "return " + utostr(i + 1) + ";")); } OS << "unsigned " << Target.getName() << AsmParser->getValueAsString("AsmParserClassName") << "::MatchRegisterName(const StringRef &Name) {\n"; EmitStringMatcher("Name", Matches, OS); OS << " return 0;\n"; OS << "}\n\n"; } void AsmMatcherEmitter::run(raw_ostream &OS) { CodeGenTarget Target; Record *AsmParser = Target.getAsmParser(); std::string ClassName = AsmParser->getValueAsString("AsmParserClassName"); // Compute the information on the instructions to match. AsmMatcherInfo Info(AsmParser); Info.BuildInfo(Target); // Sort the instruction table using the partial order on classes. std::sort(Info.Instructions.begin(), Info.Instructions.end(), less_ptr<InstructionInfo>()); DEBUG_WITH_TYPE("instruction_info", { for (std::vector<InstructionInfo*>::iterator it = Info.Instructions.begin(), ie = Info.Instructions.end(); it != ie; ++it) (*it)->dump(); }); // Check for ambiguous instructions. unsigned NumAmbiguous = 0; for (unsigned i = 0, e = Info.Instructions.size(); i != e; ++i) { for (unsigned j = i + 1; j != e; ++j) { InstructionInfo &A = *Info.Instructions[i]; InstructionInfo &B = *Info.Instructions[j]; if (A.CouldMatchAmiguouslyWith(B)) { DEBUG_WITH_TYPE("ambiguous_instrs", { errs() << "warning: ambiguous instruction match:\n"; A.dump(); errs() << "\nis incomparable with:\n"; B.dump(); errs() << "\n\n"; }); ++NumAmbiguous; } } } if (NumAmbiguous) DEBUG_WITH_TYPE("ambiguous_instrs", { errs() << "warning: " << NumAmbiguous << " ambiguous instructions!\n"; }); // Write the output. EmitSourceFileHeader("Assembly Matcher Source Fragment", OS); // Emit the function to match a register name to number. EmitMatchRegisterName(Target, AsmParser, OS); // Generate the unified function to convert operands into an MCInst. EmitConvertToMCInst(Target, Info.Instructions, OS); // Emit the enumeration for classes which participate in matching. EmitMatchClassEnumeration(Target, Info.Classes, OS); // Emit the routine to match token strings to their match class. EmitMatchTokenString(Target, Info.Classes, OS); // Emit the routine to classify an operand. EmitClassifyOperand(Target, Info, OS); // Emit the subclass predicate routine. EmitIsSubclass(Target, Info.Classes, OS); // Finally, build the match function. size_t MaxNumOperands = 0; for (std::vector<InstructionInfo*>::const_iterator it = Info.Instructions.begin(), ie = Info.Instructions.end(); it != ie; ++it) MaxNumOperands = std::max(MaxNumOperands, (*it)->Operands.size()); OS << "bool " << Target.getName() << ClassName << "::MatchInstruction(" << "SmallVectorImpl<" << Target.getName() << "Operand> &Operands, " << "MCInst &Inst) {\n"; // Emit the static match table; unused classes get initalized to 0 which is // guaranteed to be InvalidMatchClass. // // FIXME: We can reduce the size of this table very easily. First, we change // it so that store the kinds in separate bit-fields for each index, which // only needs to be the max width used for classes at that index (we also need // to reject based on this during classification). If we then make sure to // order the match kinds appropriately (putting mnemonics last), then we // should only end up using a few bits for each class, especially the ones // following the mnemonic. OS << " static const struct MatchEntry {\n"; OS << " unsigned Opcode;\n"; OS << " ConversionKind ConvertFn;\n"; OS << " MatchClassKind Classes[" << MaxNumOperands << "];\n"; OS << " } MatchTable[" << Info.Instructions.size() << "] = {\n"; for (std::vector<InstructionInfo*>::const_iterator it = Info.Instructions.begin(), ie = Info.Instructions.end(); it != ie; ++it) { InstructionInfo &II = **it; OS << " { " << Target.getName() << "::" << II.InstrName << ", " << II.ConversionFnKind << ", { "; for (unsigned i = 0, e = II.Operands.size(); i != e; ++i) { InstructionInfo::Operand &Op = II.Operands[i]; if (i) OS << ", "; OS << Op.Class->Name; } OS << " } },\n"; } OS << " };\n\n"; // Emit code to compute the class list for this operand vector. OS << " // Eliminate obvious mismatches.\n"; OS << " if (Operands.size() > " << MaxNumOperands << ")\n"; OS << " return true;\n\n"; OS << " // Compute the class list for this operand vector.\n"; OS << " MatchClassKind Classes[" << MaxNumOperands << "];\n"; OS << " for (unsigned i = 0, e = Operands.size(); i != e; ++i) {\n"; OS << " Classes[i] = ClassifyOperand(Operands[i]);\n\n"; OS << " // Check for invalid operands before matching.\n"; OS << " if (Classes[i] == InvalidMatchClass)\n"; OS << " return true;\n"; OS << " }\n\n"; OS << " // Mark unused classes.\n"; OS << " for (unsigned i = Operands.size(), e = " << MaxNumOperands << "; " << "i != e; ++i)\n"; OS << " Classes[i] = InvalidMatchClass;\n\n"; // Emit code to search the table. OS << " // Search the table.\n"; OS << " for (const MatchEntry *it = MatchTable, " << "*ie = MatchTable + " << Info.Instructions.size() << "; it != ie; ++it) {\n"; for (unsigned i = 0; i != MaxNumOperands; ++i) { OS << " if (!IsSubclass(Classes[" << i << "], it->Classes[" << i << "]))\n"; OS << " continue;\n"; } OS << "\n"; OS << " return ConvertToMCInst(it->ConvertFn, Inst, " << "it->Opcode, Operands);\n"; OS << " }\n\n"; OS << " return true;\n"; OS << "}\n\n"; }