text: //==-- WebAssemblyTargetStreamer.cpp - WebAssembly Target Streamer Methods --=//
  //
  // 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
  //
  //===----------------------------------------------------------------------===//
  ///
  /// \file
  /// This file defines WebAssembly-specific target streamer classes.
  /// These are for implementing support for target-specific assembly directives.
  ///
  //===----------------------------------------------------------------------===//
  
  #include "MCTargetDesc/WebAssemblyTargetStreamer.h"
  #include "MCTargetDesc/WebAssemblyInstPrinter.h"
  #include "MCTargetDesc/WebAssemblyMCTargetDesc.h"
  #include "llvm/MC/MCContext.h"
  #include "llvm/MC/MCSectionWasm.h"
  #include "llvm/MC/MCSubtargetInfo.h"
  #include "llvm/MC/MCSymbolWasm.h"
  #include "llvm/Support/Casting.h"
  #include "llvm/Support/ErrorHandling.h"
  #include "llvm/Support/FormattedStream.h"
  using namespace llvm;
  
  WebAssemblyTargetStreamer::WebAssemblyTargetStreamer(MCStreamer &S)
      : MCTargetStreamer(S) {}
  
  void WebAssemblyTargetStreamer::emitValueType(wasm::ValType Type) {
    Streamer.emitIntValue(uint8_t(Type), 1);
  }
  
  WebAssemblyTargetAsmStreamer::WebAssemblyTargetAsmStreamer(
      MCStreamer &S, formatted_raw_ostream &OS)
      : WebAssemblyTargetStreamer(S), OS(OS) {}
  
  WebAssemblyTargetWasmStreamer::WebAssemblyTargetWasmStreamer(MCStreamer &S)
      : WebAssemblyTargetStreamer(S) {}
  
  static void printTypes(formatted_raw_ostream &OS,
                         ArrayRef<wasm::ValType> Types) {
    bool First = true;
    for (auto Type : Types) {
      if (First)
        First = false;
      else
        OS << ", ";
      OS << WebAssembly::typeToString(Type);
    }
    OS << '\n';
  }
  
  void WebAssemblyTargetAsmStreamer::emitLocal(ArrayRef<wasm::ValType> Types) {
    if (!Types.empty()) {
      OS << "\t.local  \t";
      printTypes(OS, Types);
    }
  }
  
  void WebAssemblyTargetAsmStreamer::emitEndFunc() { OS << "\t.endfunc\n"; }
  
  void WebAssemblyTargetAsmStreamer::emitFunctionType(const MCSymbolWasm *Sym) {
    assert(Sym->isFunction());
    OS << "\t.functype\t" << Sym->getName() << " ";
    OS << WebAssembly::signatureToString(Sym->getSignature());
    OS << "\n";
  }
  
  void WebAssemblyTargetAsmStreamer::emitGlobalType(const MCSymbolWasm *Sym) {
    assert(Sym->isGlobal());
    OS << "\t.globaltype\t" << Sym->getName() << ", "
       << WebAssembly::typeToString(
              static_cast<wasm::ValType>(Sym->getGlobalType().Type));
    if (!Sym->getGlobalType().Mutable)
      OS << ", immutable";
    OS << '\n';
  }
  
  void WebAssemblyTargetAsmStreamer::emitEventType(const MCSymbolWasm *Sym) {
    assert(Sym->isEvent());
    OS << "\t.eventtype\t" << Sym->getName() << " ";
    OS << WebAssembly::typeListToString(Sym->getSignature()->Params);
    OS << "\n";
  }
  
  void WebAssemblyTargetAsmStreamer::emitImportModule(const MCSymbolWasm *Sym,
                                                      StringRef ImportModule) {
    OS << "\t.import_module\t" << Sym->getName() << ", "
                               << ImportModule << '\n';
  }
  
  void WebAssemblyTargetAsmStreamer::emitImportName(const MCSymbolWasm *Sym,
                                                    StringRef ImportName) {
    OS << "\t.import_name\t" << Sym->getName() << ", "
                             << ImportName << '\n';
  }
  
  void WebAssemblyTargetAsmStreamer::emitExportName(const MCSymbolWasm *Sym,
                                                    StringRef ExportName) {
    OS << "\t.export_name\t" << Sym->getName() << ", "
                             << ExportName << '\n';
  }
  
  void WebAssemblyTargetAsmStreamer::emitIndIdx(const MCExpr *Value) {
    OS << "\t.indidx  \t" << *Value << '\n';
  }
  
  void WebAssemblyTargetWasmStreamer::emitLocal(ArrayRef<wasm::ValType> Types) {
    SmallVector<std::pair<wasm::ValType, uint32_t>, 4> Grouped;
    for (auto Type : Types) {
      if (Grouped.empty() || Grouped.back().first != Type)
        Grouped.push_back(std::make_pair(Type, 1));
      else
        ++Grouped.back().second;
    }
  
    Streamer.emitULEB128IntValue(Grouped.size());
    for (auto Pair : Grouped) {
      Streamer.emitULEB128IntValue(Pair.second);
      emitValueType(Pair.first);
    }
  }
  
  void WebAssemblyTargetWasmStreamer::emitEndFunc() {
    llvm_unreachable(".end_func is not needed for direct wasm output");
  }
  
  void WebAssemblyTargetWasmStreamer::emitIndIdx(const MCExpr *Value) {
    llvm_unreachable(".indidx encoding not yet implemented");
  }
  