[llvm] [NFC][TableGen] Adopt CodeGenHelpers in InstrInfoEmitter (PR #166442)

[Rahul Joshi via llvm-commits]

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@@ -383,38 +383,35 @@ void InstrInfoEmitter::emitOperandNameMappings(
   const size_t NumOperandNames = OperandNameToID.size();
   const unsigned MaxNumOperands = MaxOperandNo + 1;
 
-  OS << "#ifdef GET_INSTRINFO_OPERAND_ENUM\n";
-  OS << "#undef GET_INSTRINFO_OPERAND_ENUM\n";
-  OS << "namespace llvm::" << Namespace << " {\n";
-
-  assert(NumOperandNames <= UINT16_MAX &&
-         "Too many operands for the operand index -> name table");
-  StringRef EnumType = getMinimalTypeForRange(NumOperandNames);
-  OS << "enum class OpName : " << EnumType << " {\n";
-  for (const auto &[Op, I] : OperandNameToID)
-    OS << "  " << Op << " = " << I << ",\n";
-  OS << "  NUM_OPERAND_NAMES = " << NumOperandNames << ",\n";
-  OS << "}; // enum class OpName\n\n";
-
-  OS << "LLVM_READONLY int16_t getNamedOperandIdx(uint16_t Opcode, OpName "
-        "Name);\n";
-  OS << "LLVM_READONLY OpName getOperandIdxName(uint16_t Opcode, int16_t "
-        "Idx);\n";
-  OS << "} // end namespace llvm::" << Namespace << '\n';
-  OS << "#endif //GET_INSTRINFO_OPERAND_ENUM\n\n";
-
-  OS << "#ifdef GET_INSTRINFO_NAMED_OPS\n";
-  OS << "#undef GET_INSTRINFO_NAMED_OPS\n";
-  OS << "namespace llvm::" << Namespace << " {\n";
-
-  emitGetInstructionIndexForOpLookup(OS, OperandMap, InstructionIndex);
+  const std::string LlvmNamespace = ("llvm::" + Namespace).str();
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jurahul wrote:

Done. SmallString has a constructor that does concatenation, so used that instead of building a Twine and then calling .str() on it

https://github.com/llvm/llvm-project/pull/166442