llvm/lib/TableGen/TableGenBackendSkeleton.cpp

//===- TableGenBackendSkeleton.cpp - Skeleton TableGen backend --*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This Tablegen backend emits ...
//
//===----------------------------------------------------------------------===//

#include "llvm/ADT/StringRef.h"
#include "llvm/TableGen/TableGenBackend.h"

#define DEBUG_TYPE "skeleton-emitter"

namespace llvm {
class RecordKeeper;
class raw_ostream;
} // namespace llvm

using namespace llvm;

namespace {

// Any helper data structures can be defined here. Some backends use
// structs to collect information from the records.

class SkeletonEmitter {
private:
  const RecordKeeper &Records;

public:
  SkeletonEmitter(const RecordKeeper &RK) : Records(RK) {}

  void run(raw_ostream &OS);
}; // emitter class

} // anonymous namespace

void SkeletonEmitter::run(raw_ostream &OS) {
  emitSourceFileHeader("Skeleton data structures", OS);

  (void)Records; // To suppress unused variable warning; remove on use.
}

// Choose either option A or B.

//===----------------------------------------------------------------------===//
// Option A: Register the backed as class <SkeletonEmitter>
static TableGen::Emitter::OptClass<SkeletonEmitter>
    X("gen-skeleton-class", "Generate example skeleton class");

//===----------------------------------------------------------------------===//
// Option B: Register "EmitSkeleton" directly
// The emitter entry may be private scope.
static void EmitSkeleton(const RecordKeeper &RK, raw_ostream &OS) {
  // Instantiate the emitter class and invoke run().
  SkeletonEmitter(RK).run(OS);
}

static TableGen::Emitter::Opt Y("gen-skeleton-entry", EmitSkeleton,
                                "Generate example skeleton entry");