FIREmitter.cpp

Go to the documentation of this file.

//===- FIREmitter.cpp - FIRRTL dialect to .fir emitter --------------------===//
//
// 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 implements a .fir file emitter.
//
//===----------------------------------------------------------------------===//
 
#include "circt/Dialect/FIRRTL/FIREmitter.h"
#include "circt/Dialect/FIRRTL/CHIRRTLDialect.h"
#include "circt/Dialect/FIRRTL/FIRParser.h"
#include "circt/Dialect/FIRRTL/FIRRTLDialect.h"
#include "circt/Dialect/FIRRTL/FIRRTLOps.h"
#include "circt/Dialect/FIRRTL/Namespace.h"
#include "circt/Support/LLVM.h"
#include "circt/Support/PrettyPrinterHelpers.h"
#include "mlir/IR/BuiltinOps.h"
#include "mlir/Tools/mlir-translate/Translation.h"
#include "llvm/ADT/APSInt.h"
#include "llvm/ADT/StringSet.h"
#include "llvm/ADT/TypeSwitch.h"
#include "llvm/Support/Debug.h"
 
#define DEBUG_TYPE "export-firrtl"
 
using namespace circt;
using namespace firrtl;
using namespace chirrtl;
using namespace pretty;
 
//===----------------------------------------------------------------------===//
// Emitter
//===----------------------------------------------------------------------===//
 
// NOLINTBEGIN(misc-no-recursion)
namespace {
 
constexpr size_t defaultTargetLineLength = 80;
 
/// An emitter for FIRRTL dialect operations to .fir output.
struct Emitter {
  Emitter(llvm::raw_ostream &os, FIRVersion version,
          size_t targetLineLength = defaultTargetLineLength)
      : pp(os, targetLineLength), ps(pp, saver), version(version) {
    pp.setListener(&saver);
  }
  LogicalResult finalize();
 
  // Circuit/module emission
  void emitCircuit(CircuitOp op);
  void emitModule(FModuleOp op);
  void emitModule(FExtModuleOp op);
  void emitModule(FIntModuleOp op);
  void emitModulePorts(ArrayRef<PortInfo> ports,
                       Block::BlockArgListType arguments = {});
  void emitModuleParameters(Operation *op, ArrayAttr parameters);
  void emitDeclaration(DomainOp op);
  void emitDeclaration(LayerOp op);
  void emitDeclaration(OptionOp op);
  void emitDeclaration(FormalOp op);
  void emitDeclaration(SimulationOp op);
  void emitFormalLike(Operation *op, StringRef keyword, StringAttr symName,
                      StringAttr moduleName, DictionaryAttr params);
  void emitEnabledLayers(ArrayRef<Attribute> layers);
  void emitKnownLayers(ArrayRef<Attribute> layers);
  void emitParamAssign(ParamDeclAttr param, Operation *op,
                       std::optional<PPExtString> wordBeforeLHS = std::nullopt);
  void emitParamValue(Attribute value, Operation *op);
 
  void emitGenericIntrinsic(GenericIntrinsicOp op);
 
  // Statement emission
  void emitStatementsInBlock(Block &block);
  void emitStatement(WhenOp op);
  void emitStatement(WireOp op);
  void emitStatement(RegOp op);
  void emitStatement(RegResetOp op);
  void emitStatement(NodeOp op);
  void emitStatement(StopOp op);
  void emitStatement(SkipOp op);
  void emitFormatString(Operation *op, StringRef formatString, OperandRange ops,
                        llvm::SmallVectorImpl<Value> &substitutions);
  template <class T>
  void emitPrintfLike(T op, StringAttr fileName);
  void emitStatement(PrintFOp op);
  void emitStatement(FPrintFOp op);
  void emitStatement(FFlushOp op);
  void emitStatement(ConnectOp op);
  void emitStatement(MatchingConnectOp op);
  void emitStatement(PropAssignOp op);
  void emitStatement(InstanceOp op);
  void emitStatement(InstanceChoiceOp op);
  void emitStatement(AttachOp op);
  void emitStatement(MemOp op);
  void emitStatement(InvalidValueOp op);
  void emitStatement(CombMemOp op);
  void emitStatement(SeqMemOp op);
  void emitStatement(MemoryPortOp op);
  void emitStatement(MemoryDebugPortOp op);
  void emitStatement(MemoryPortAccessOp op);
  void emitStatement(RefDefineOp op);
  void emitStatement(RefForceOp op);
  void emitStatement(RefForceInitialOp op);
  void emitStatement(RefReleaseOp op);
  void emitStatement(RefReleaseInitialOp op);
  void emitStatement(LayerBlockOp op);
  void emitStatement(GenericIntrinsicOp op);
 
  template <class T>
  void emitVerifStatement(T op, StringRef mnemonic);
  void emitStatement(AssertOp op) { emitVerifStatement(op, "assert"); }
  void emitStatement(AssumeOp op) { emitVerifStatement(op, "assume"); }
  void emitStatement(CoverOp op) { emitVerifStatement(op, "cover"); }
 
  // Exprsesion emission
  void emitExpression(Value value);
  void emitExpression(ConstantOp op);
  void emitExpression(SpecialConstantOp op);
  void emitExpression(SubfieldOp op);
  void emitExpression(SubindexOp op);
  void emitExpression(SubaccessOp op);
  void emitExpression(OpenSubfieldOp op);
  void emitExpression(OpenSubindexOp op);
  void emitExpression(RefResolveOp op);
  void emitExpression(RefSendOp op);
  void emitExpression(RefSubOp op);
  void emitExpression(RWProbeOp op);
  void emitExpression(RefCastOp op);
  void emitExpression(UninferredResetCastOp op);
  void emitExpression(ConstCastOp op);
  void emitExpression(StringConstantOp op);
  void emitExpression(FIntegerConstantOp op);
  void emitExpression(BoolConstantOp op);
  void emitExpression(DoubleConstantOp op);
  void emitExpression(ListCreateOp op);
  void emitExpression(UnresolvedPathOp op);
  void emitExpression(GenericIntrinsicOp op);
  void emitExpression(CatPrimOp op);
  void emitExpression(UnsafeDomainCastOp op);
 
  void emitPrimExpr(StringRef mnemonic, Operation *op,
                    ArrayRef<uint32_t> attrs = {});
 
  void emitExpression(BitsPrimOp op) {
    emitPrimExpr("bits", op, {op.getHi(), op.getLo()});
  }
  void emitExpression(HeadPrimOp op) {
    emitPrimExpr("head", op, op.getAmount());
  }
  void emitExpression(TailPrimOp op) {
    emitPrimExpr("tail", op, op.getAmount());
  }
  void emitExpression(PadPrimOp op) { emitPrimExpr("pad", op, op.getAmount()); }
  void emitExpression(ShlPrimOp op) { emitPrimExpr("shl", op, op.getAmount()); }
  void emitExpression(ShrPrimOp op) { emitPrimExpr("shr", op, op.getAmount()); }
 
  void emitExpression(TimeOp op){};
 
  // Funnel all ops without attrs into `emitPrimExpr`.
#define HANDLE(OPTYPE, MNEMONIC)                                               \
  void emitExpression(OPTYPE op) { emitPrimExpr(MNEMONIC, op); }
  HANDLE(AddPrimOp, "add");
  HANDLE(SubPrimOp, "sub");
  HANDLE(MulPrimOp, "mul");
  HANDLE(DivPrimOp, "div");
  HANDLE(RemPrimOp, "rem");
  HANDLE(AndPrimOp, "and");
  HANDLE(OrPrimOp, "or");
  HANDLE(XorPrimOp, "xor");
  HANDLE(LEQPrimOp, "leq");
  HANDLE(LTPrimOp, "lt");
  HANDLE(GEQPrimOp, "geq");
  HANDLE(GTPrimOp, "gt");
  HANDLE(EQPrimOp, "eq");
  HANDLE(NEQPrimOp, "neq");
  HANDLE(DShlPrimOp, "dshl");
  HANDLE(DShlwPrimOp, "dshlw");
  HANDLE(DShrPrimOp, "dshr");
  HANDLE(MuxPrimOp, "mux");
  HANDLE(AsSIntPrimOp, "asSInt");
  HANDLE(AsUIntPrimOp, "asUInt");
  HANDLE(AsAsyncResetPrimOp, "asAsyncReset");
  HANDLE(AsClockPrimOp, "asClock");
  HANDLE(CvtPrimOp, "cvt");
  HANDLE(NegPrimOp, "neg");
  HANDLE(NotPrimOp, "not");
  HANDLE(AndRPrimOp, "andr");
  HANDLE(OrRPrimOp, "orr");
  HANDLE(XorRPrimOp, "xorr");
#undef HANDLE
 
  // Attributes
  void emitAttribute(MemDirAttr attr);
  void emitAttribute(RUWBehaviorAttr attr);
 
  // Types
  void emitType(Type type, bool includeConst = true);
  void emitTypeWithColon(Type type) {
    ps << PP::space << ":" << PP::nbsp;
    emitType(type);
  }
 
  // Domains
  void emitDomains(Attribute domains,
                   const DenseMap<size_t, StringRef> &domainMap);
 
  // Locations
  void emitLocation(Location loc);
  void emitLocation(Operation *op) { emitLocation(op->getLoc()); }
  template <typename... Args>
  void emitLocationAndNewLine(Args... args) {
    // Break so previous content is not impacted by following,
    // but use a 'neverbreak' so it always fits.
    ps << PP::neverbreak;
    emitLocation(args...);
    setPendingNewline();
  }
 
  void emitAssignLike(llvm::function_ref<void()> emitLHS,
                      llvm::function_ref<void()> emitRHS,
                      PPExtString syntax = PPExtString("="),
                      std::optional<PPExtString> wordBeforeLHS = std::nullopt) {
    // If wraps, indent.
    ps.scopedBox(PP::ibox2, [&]() {
      if (wordBeforeLHS) {
        ps << *wordBeforeLHS << PP::space;
      }
      emitLHS();
      // Allow breaking before 'syntax' (e.g., '=') if long assignment.
      ps << PP::space << syntax << PP::nbsp; /* PP::space; */
      // RHS is boxed to right of the syntax.
      ps.scopedBox(PP::ibox0, [&]() { emitRHS(); });
    });
  }
 
  /// Emit the specified value as a subexpression, wrapping in an ibox2.
  void emitSubExprIBox2(Value v) {
    ps.scopedBox(PP::ibox2, [&]() { emitExpression(v); });
  }
 
  /// Emit a range of values separated by commas and a breakable space.
  /// Each value is emitted by invoking `eachFn`.
  template <typename Container, typename EachFn>
  void interleaveComma(const Container &c, EachFn eachFn) {
    llvm::interleave(c, eachFn, [&]() { ps << "," << PP::space; });
  }
 
  /// Emit a range of values separated by commas and a breakable space.
  /// Each value is emitted in an ibox2.
  void interleaveComma(ValueRange ops) {
    return interleaveComma(ops, [&](Value v) { emitSubExprIBox2(v); });
  }
 
  void emitStatementFunctionOp(PPExtString name, Operation *op) {
    startStatement();
    ps << name << "(";
    ps.scopedBox(PP::ibox0, [&]() {
      interleaveComma(op->getOperands());
      ps << ")";
    });
    emitLocationAndNewLine(op);
  }
 
  template <typename EachFn, typename Range>
  void emitLiteralExpression(Type type, const Range &r, EachFn eachFn) {
    emitType(type);
    ps << "(";
    ps.scopedBox(PP::ibox0, [&]() {
      interleaveComma(r, eachFn);
      ps << ")";
    });
  }
 
  void emitLiteralExpression(Type type, ValueRange values) {
    return emitLiteralExpression(type, values,
                                 [&](Value v) { emitSubExprIBox2(v); });
  }
 
  /// Emit a (potentially nested) symbol reference as `A.B.C`.
  void emitSymbol(SymbolRefAttr symbol) {
    ps.ibox(2, IndentStyle::Block);
    ps << symbol.getRootReference();
    for (auto nested : symbol.getNestedReferences()) {
      ps.zerobreak();
      ps << ".";
      ps << nested.getAttr();
    }
    ps.end();
  }
 
private:
  /// Emit an error and remark that emission failed.
  InFlightDiagnostic emitError(Operation *op, const Twine &message) {
    encounteredError = true;
    return op->emitError(message);
  }
 
  /// Emit an error and remark that emission failed.
  InFlightDiagnostic emitOpError(Operation *op, const Twine &message) {
    encounteredError = true;
    return op->emitOpError(message);
  }
 
  /// Return the name used during emission of a `Value`, or none if the value
  /// has not yet been emitted or it was emitted inline.
  std::optional<StringRef> lookupEmittedName(Value value) {
    auto it = valueNames.find(value);
    if (it != valueNames.end())
      return {it->second};
    return {};
  }
 
  /// If previous emission requires a newline, emit it now.
  /// This gives us opportunity to open/close boxes before linebreak.
  void emitPendingNewlineIfNeeded() {
    if (pendingNewline) {
      pendingNewline = false;
      ps << PP::newline;
    }
  }
  void setPendingNewline() {
    assert(!pendingNewline);
    pendingNewline = true;
  }
 
  void startStatement() { emitPendingNewlineIfNeeded(); }
 
private:
  /// String storage backing Tokens built from temporary strings.
  /// PrettyPrinter will clear this as appropriate.
  TokenStringSaver saver;
 
  /// Pretty printer.
  PrettyPrinter pp;
 
  /// Stream helper (pp, saver).
  TokenStream<> ps;
 
  /// Whether a newline is expected, emitted late to provide opportunity to
  /// open/close boxes we don't know we need at level of individual statement.
  /// Every statement should set this instead of directly emitting (last)
  /// newline. Most statements end with emitLocationInfoAndNewLine which handles
  /// this.
  bool pendingNewline = false;
 
  /// Whether we have encountered any errors during emission.
  bool encounteredError = false;
 
  /// The names used to emit values already encountered. Anything that gets a
  /// name in the output FIR is listed here, such that future expressions can
  /// reference it.
  DenseMap<Value, StringRef> valueNames;
  StringSet<> valueNamesStorage;
 
  /// Legalize names for emission.  Convert names which begin with a number to
  /// be escaped using backticks.
  StringAttr legalize(StringAttr attr) {
    StringRef str = attr.getValue();
    if (str.empty() || !isdigit(str.front()))
      return attr;
    return StringAttr::get(attr.getContext(), "`" + Twine(attr) + "`");
  }
 
  void addValueName(Value value, StringAttr attr) {
    valueNames.insert({value, attr.getValue()});
  }
  void addValueName(Value value, StringRef str) {
    auto it = valueNamesStorage.insert(str);
    valueNames.insert({value, it.first->getKey()});
  }
  void addForceable(Forceable op, StringAttr attr) {
    addValueName(op.getData(), attr);
    if (op.isForceable()) {
      SmallString<32> rwName;
      (Twine("rwprobe(") + attr.strref() + ")").toVector(rwName);
      addValueName(op.getDataRef(), rwName);
    }
  }
 
  /// The current circuit namespace valid within the call to `emitCircuit`.
  CircuitNamespace circuitNamespace;
 
  /// Symbol and Inner Symbol analyses, valid within the call to `emitCircuit`.
  struct SymInfos {
    SymbolTable symbolTable;
    hw::InnerSymbolTableCollection istc;
    hw::InnerRefNamespace irn{symbolTable, istc};
    SymInfos(Operation *op) : symbolTable(op), istc(op){};
  };
  std::optional<std::reference_wrapper<SymInfos>> symInfos;
 
  /// The version of the FIRRTL spec that should be emitted.
  FIRVersion version;
};
} // namespace
 
LogicalResult Emitter::finalize() { return failure(encounteredError); }
 
/// Emit an entire circuit.
void Emitter::emitCircuit(CircuitOp op) {
  circuitNamespace.add(op);
  SymInfos circuitSymInfos(op);
  symInfos = circuitSymInfos;
  startStatement();
  ps << "FIRRTL version ";
  ps.addAsString(version.major);
  ps << ".";
  ps.addAsString(version.minor);
  ps << ".";
  ps.addAsString(version.patch);
  ps << PP::newline;
  ps << "circuit " << PPExtString(legalize(op.getNameAttr())) << " :";
  setPendingNewline();
  ps.scopedBox(PP::bbox2, [&]() {
    for (auto &bodyOp : *op.getBodyBlock()) {
      if (encounteredError)
        break;
      TypeSwitch<Operation *>(&bodyOp)
          .Case<FModuleOp, FExtModuleOp, FIntModuleOp>([&](auto op) {
            emitModule(op);
            ps << PP::newline;
          })
          .Case<DomainOp, LayerOp, OptionOp, FormalOp, SimulationOp>(
              [&](auto op) { emitDeclaration(op); })
          .Default([&](auto op) {
            emitOpError(op, "not supported for emission inside circuit");
          });
    }
  });
  circuitNamespace.clear();
  symInfos = std::nullopt;
}
 
void Emitter::emitEnabledLayers(ArrayRef<Attribute> layers) {
  for (auto layer : layers) {
    ps << PP::space;
    ps.cbox(2, IndentStyle::Block);
    ps << "enablelayer" << PP::space;
    emitSymbol(cast<SymbolRefAttr>(layer));
    ps << PP::end;
  }
}
 
void Emitter::emitKnownLayers(ArrayRef<Attribute> layers) {
  for (auto layer : layers) {
    ps << PP::space;
    ps.cbox(2, IndentStyle::Block);
    ps << "knownlayer" << PP::space;
    emitSymbol(cast<SymbolRefAttr>(layer));
    ps << PP::end;
  }
}
 
void Emitter::emitParamAssign(ParamDeclAttr param, Operation *op,
                              std::optional<PPExtString> wordBeforeLHS) {
  if (wordBeforeLHS) {
    ps << *wordBeforeLHS << PP::nbsp;
  }
  ps << PPExtString(param.getName().strref()) << PP::nbsp << "=" << PP::nbsp;
  emitParamValue(param.getValue(), op);
}
 
void Emitter::emitParamValue(Attribute value, Operation *op) {
  TypeSwitch<Attribute>(value)
      .Case<IntegerAttr>([&](auto attr) { ps.addAsString(attr.getValue()); })
      .Case<FloatAttr>([&](auto attr) {
        SmallString<16> str;
        attr.getValue().toString(str);
        ps << str;
      })
      .Case<StringAttr>(
          [&](auto attr) { ps.writeQuotedEscaped(attr.getValue()); })
      .Case<ArrayAttr>([&](auto attr) {
        ps.scopedBox(PP::bbox2, [&]() {
          ps << "[";
          interleaveComma(attr.getValue(),
                          [&](auto element) { emitParamValue(element, op); });
          ps << "]";
        });
      })
      .Case<DictionaryAttr>([&](auto attr) {
        ps.scopedBox(PP::bbox2, [&]() {
          ps << "{";
          interleaveComma(attr.getValue(), [&](auto field) {
            ps << PPExtString(field.getName()) << PP::nbsp << "=" << PP::nbsp;
            emitParamValue(field.getValue(), op);
          });
          ps << "}";
        });
      })
      .Default([&](auto attr) {
        emitOpError(op, "with unsupported parameter attribute: ") << attr;
        ps << "<unsupported-attr ";
        ps.addAsString(attr);
        ps << ">";
      });
}
 
void Emitter::emitGenericIntrinsic(GenericIntrinsicOp op) {
  ps << "intrinsic(";
  ps.scopedBox(PP::cbox0, [&]() {
    ps.scopedBox(PP::ibox2, [&]() {
      ps << op.getIntrinsic();
      ps.scopedBox(PP::ibox0, [&]() {
        auto params = op.getParameters();
        if (!params.empty()) {
          ps << "<";
          ps.scopedBox(PP::ibox0, [&]() {
            interleaveComma(
                params.getAsRange<ParamDeclAttr>(),
                [&](ParamDeclAttr param) { emitParamAssign(param, op); });
          });
          ps << ">";
        }
      });
      if (op.getNumResults() != 0)
        emitTypeWithColon(op.getResult().getType());
    });
    if (op.getNumOperands() != 0) {
      ps << "," << PP::space;
      ps.scopedBox(PP::ibox0, [&]() { interleaveComma(op->getOperands()); });
    }
    ps << ")";
  });
}
 
/// Emit an entire module.
void Emitter::emitModule(FModuleOp op) {
  startStatement();
  ps.cbox(4, IndentStyle::Block);
  if (op.isPublic())
    ps << "public" << PP::nbsp;
  ps << "module " << PPExtString(legalize(op.getNameAttr()));
  emitEnabledLayers(op.getLayers());
  ps << PP::nbsp << ":" << PP::end;
  emitLocation(op);
 
  ps.scopedBox(PP::bbox2, [&]() {
    setPendingNewline();
 
    // Emit the ports.
    auto ports = op.getPorts();
    emitModulePorts(ports, op.getArguments());
    if (!ports.empty() && !op.getBodyBlock()->empty())
      ps << PP::newline;
 
    // Emit the module body.
    emitStatementsInBlock(*op.getBodyBlock());
  });
  valueNames.clear();
  valueNamesStorage.clear();
}
 
/// Emit an external module.
void Emitter::emitModule(FExtModuleOp op) {
  startStatement();
  ps.cbox(4, IndentStyle::Block);
  ps << "extmodule " << PPExtString(legalize(op.getNameAttr()));
  emitKnownLayers(op.getKnownLayers());
  emitEnabledLayers(op.getLayers());
  ps << PP::nbsp << ":" << PP::end;
  emitLocation(op);
 
  ps.scopedBox(PP::bbox2, [&]() {
    setPendingNewline();
 
    // Emit the ports.
    auto ports = op.getPorts();
    emitModulePorts(ports);
 
    // Emit the optional `defname`.
    if (op.getDefname() && !op.getDefname()->empty()) {
      startStatement();
      ps << "defname = " << PPExtString(*op.getDefname());
      setPendingNewline();
    }
 
    // Emit the parameters.
    emitModuleParameters(op, op.getParameters());
  });
}
 
/// Emit an intrinsic module
void Emitter::emitModule(FIntModuleOp op) {
  startStatement();
  ps.cbox(4, IndentStyle::Block);
  ps << "intmodule " << PPExtString(legalize(op.getNameAttr()));
  emitEnabledLayers(op.getLayers());
  ps << PP::nbsp << ":" << PP::end;
  emitLocation(op);
 
  ps.scopedBox(PP::bbox2, [&]() {
    setPendingNewline();
 
    // Emit the ports.
    auto ports = op.getPorts();
    emitModulePorts(ports);
 
    startStatement();
    ps << "intrinsic = " << PPExtString(op.getIntrinsic());
    setPendingNewline();
 
    // Emit the parameters.
    emitModuleParameters(op, op.getParameters());
  });
}
 
/// Emit the ports of a module or extmodule. If the `arguments` array is
/// non-empty, it is used to populate `emittedNames` with the port names for use
/// during expression emission.
void Emitter::emitModulePorts(ArrayRef<PortInfo> ports,
                              Block::BlockArgListType arguments) {
  DenseMap<size_t, StringRef> domainMap;
  for (unsigned i = 0, e = ports.size(); i < e; ++i) {
    startStatement();
    const auto &port = ports[i];
    ps << (port.direction == Direction::In ? "input " : "output ");
    auto legalName = legalize(port.name);
    if (isa<DomainType>(port.type))
      domainMap.insert({i, port.name});
    if (!arguments.empty())
      addValueName(arguments[i], legalName);
    ps << PPExtString(legalName) << " : ";
    emitType(port.type);
    emitDomains(port.domains, domainMap);
    emitLocation(ports[i].loc);
    setPendingNewline();
  }
}
 
void Emitter::emitModuleParameters(Operation *op, ArrayAttr parameters) {
  for (auto param : parameters.getAsRange<ParamDeclAttr>()) {
    startStatement();
    emitParamAssign(param, op, PPExtString("parameter"));
    setPendingNewline();
  }
}
 
void Emitter::emitDeclaration(DomainOp op) {
  startStatement();
  ps << "domain " << PPExtString(op.getSymName()) << " :";
  emitLocationAndNewLine(op);
}
 
/// Emit a layer definition.
void Emitter::emitDeclaration(LayerOp op) {
  startStatement();
  ps << "layer " << PPExtString(op.getSymName()) << ", "
     << PPExtString(stringifyLayerConvention(op.getConvention()));
 
  if (auto outputFile = op->getAttrOfType<hw::OutputFileAttr>("output_file")) {
    ps << ", ";
    ps.writeQuotedEscaped(outputFile.getFilename().getValue());
  }
 
  ps << " : ";
  emitLocationAndNewLine(op);
  ps.scopedBox(PP::bbox2, [&]() {
    for (auto &bodyOp : op.getBody().getOps()) {
      TypeSwitch<Operation *>(&bodyOp)
          .Case<LayerOp>([&](auto op) { emitDeclaration(op); })
          .Default([&](auto op) {
            emitOpError(op,
                        "not supported for emission inside layer definition");
          });
    }
  });
}
 
/// Emit an option declaration.
void Emitter::emitDeclaration(OptionOp op) {
  startStatement();
  ps << "option " << PPExtString(legalize(op.getSymNameAttr())) << " :";
  emitLocation(op);
  ps.scopedBox(PP::bbox2, [&] {
    for (auto caseOp : op.getBody().getOps<OptionCaseOp>()) {
      ps << PP::newline;
      ps << PPExtString(legalize(caseOp.getSymNameAttr()));
      emitLocation(caseOp);
    }
  });
  ps << PP::newline << PP::newline;
}
 
/// Emit a formal test definition.
void Emitter::emitDeclaration(FormalOp op) {
  emitFormalLike(op, "formal", op.getSymNameAttr(),
                 op.getModuleNameAttr().getAttr(), op.getParameters());
}
 
/// Emit a simulation test definition.
void Emitter::emitDeclaration(SimulationOp op) {
  emitFormalLike(op, "simulation", op.getSymNameAttr(),
                 op.getModuleNameAttr().getAttr(), op.getParameters());
}
 
/// Emit a formal or simulation test definition.
void Emitter::emitFormalLike(Operation *op, StringRef keyword,
                             StringAttr symName, StringAttr moduleName,
                             DictionaryAttr params) {
  startStatement();
  ps.cbox(4, IndentStyle::Block);
  ps << keyword << " " << PPExtString(legalize(symName));
  ps << " of " << PPExtString(legalize(moduleName));
  ps << PP::nbsp << ":" << PP::end;
  emitLocation(op);
 
  ps.scopedBox(PP::bbox2, [&]() {
    setPendingNewline();
    for (auto param : params) {
      startStatement();
      ps << PPExtString(param.getName()) << PP::nbsp << "=" << PP::nbsp;
      emitParamValue(param.getValue(), op);
      setPendingNewline();
    }
  });
}
 
/// Check if an operation is inlined into the emission of their users. For
/// example, subfields are always inlined.
static bool isEmittedInline(Operation *op) {
  // FIRRTL expressions are statically classified as always inlineable.
  // InvalidValueOp never is inlined, and is handled specially.
  // GenericIntrinsicOp is inlined if has exactly one use (only emit once)
  // that is not emitted inline.  This is to ensure it is emitted inline
  // in common cases, but only inspect one level deep.
  return (isExpression(op) && !isa<InvalidValueOp>(op)) ||
         (isa<GenericIntrinsicOp>(op) && op->hasOneUse() &&
          !isEmittedInline(*op->getUsers().begin()));
}
 
void Emitter::emitStatementsInBlock(Block &block) {
  for (auto &bodyOp : block) {
    if (encounteredError)
      return;
    if (isEmittedInline(&bodyOp))
      continue;
    TypeSwitch<Operation *>(&bodyOp)
        .Case<WhenOp, WireOp, RegOp, RegResetOp, NodeOp, StopOp, SkipOp,
              PrintFOp, FPrintFOp, FFlushOp, AssertOp, AssumeOp, CoverOp,
              ConnectOp, MatchingConnectOp, PropAssignOp, InstanceOp,
              InstanceChoiceOp, AttachOp, MemOp, InvalidValueOp, SeqMemOp,
              CombMemOp, MemoryPortOp, MemoryDebugPortOp, MemoryPortAccessOp,
              RefDefineOp, RefForceOp, RefForceInitialOp, RefReleaseOp,
              RefReleaseInitialOp, LayerBlockOp, GenericIntrinsicOp>(
            [&](auto op) { emitStatement(op); })
        .Default([&](auto op) {
          startStatement();
          ps << "// operation " << PPExtString(op->getName().getStringRef());
          setPendingNewline();
          emitOpError(op, "not supported as statement");
        });
  }
}
 
void Emitter::emitStatement(WhenOp op) {
  startStatement();
  ps << "when ";
  emitExpression(op.getCondition());
  ps << " :";
  emitLocationAndNewLine(op);
  ps.scopedBox(PP::bbox2, [&]() { emitStatementsInBlock(op.getThenBlock()); });
  // emitStatementsInBlock(op.getThenBlock());
  if (!op.hasElseRegion())
    return;
 
  startStatement();
  ps << "else ";
  // Sugar to `else when ...` if there's only a single when statement in the
  // else block.
  auto &elseBlock = op.getElseBlock();
  if (!elseBlock.empty() && &elseBlock.front() == &elseBlock.back()) {
    if (auto whenOp = dyn_cast<WhenOp>(&elseBlock.front())) {
      emitStatement(whenOp);
      return;
    }
  }
  // Otherwise print the block as `else :`.
  ps << ":";
  setPendingNewline();
  ps.scopedBox(PP::bbox2, [&]() { emitStatementsInBlock(elseBlock); });
}
 
void Emitter::emitStatement(WireOp op) {
  auto legalName = legalize(op.getNameAttr());
  addForceable(op, legalName);
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "wire " << PPExtString(legalName);
    emitTypeWithColon(op.getResult().getType());
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(RegOp op) {
  auto legalName = legalize(op.getNameAttr());
  addForceable(op, legalName);
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "reg " << PPExtString(legalName);
    emitTypeWithColon(op.getResult().getType());
    ps << "," << PP::space;
    emitExpression(op.getClockVal());
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(RegResetOp op) {
  auto legalName = legalize(op.getNameAttr());
  addForceable(op, legalName);
  startStatement();
  if (FIRVersion(3, 0, 0) <= version) {
    ps.scopedBox(PP::ibox2, [&]() {
      ps << "regreset " << legalName;
      emitTypeWithColon(op.getResult().getType());
      ps << "," << PP::space;
      emitExpression(op.getClockVal());
      ps << "," << PP::space;
      emitExpression(op.getResetSignal());
      ps << "," << PP::space;
      emitExpression(op.getResetValue());
    });
  } else {
    ps.scopedBox(PP::ibox2, [&]() {
      ps << "reg " << legalName;
      emitTypeWithColon(op.getResult().getType());
      ps << "," << PP::space;
      emitExpression(op.getClockVal());
      ps << PP::space << "with :";
      // Don't break this because of the newline.
      ps << PP::neverbreak;
      // No-paren version must be newline + indent.
      ps << PP::newline; // ibox2 will indent.
      ps << "reset => (" << PP::ibox0;
      emitExpression(op.getResetSignal());
      ps << "," << PP::space;
      emitExpression(op.getResetValue());
      ps << ")" << PP::end;
    });
  }
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(NodeOp op) {
  auto legalName = legalize(op.getNameAttr());
  addForceable(op, legalName);
  startStatement();
  emitAssignLike([&]() { ps << "node " << PPExtString(legalName); },
                 [&]() { emitExpression(op.getInput()); });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(StopOp op) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "stop(" << PP::ibox0;
    emitExpression(op.getClock());
    ps << "," << PP::space;
    emitExpression(op.getCond());
    ps << "," << PP::space;
    ps.addAsString(op.getExitCode());
    ps << ")" << PP::end;
    if (!op.getName().empty()) {
      ps << PP::space << ": " << PPExtString(legalize(op.getNameAttr()));
    }
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(SkipOp op) {
  startStatement();
  ps << "skip";
  emitLocationAndNewLine(op);
}
 
void Emitter::emitFormatString(Operation *op, StringRef origFormatString,
                               OperandRange substitutionOperands,
                               llvm::SmallVectorImpl<Value> &substitutions) {
  // Replace the generic "{{}}" special substitutions with their attributes.
  // E.g.:
  //
  //     "hello {{}} world"(%time)
  //
  // Becomes:
  //
  //     "hello {{SimulationTime}} world"
  SmallString<64> formatString;
  for (size_t i = 0, e = origFormatString.size(), opIdx = 0; i != e; ++i) {
    auto c = origFormatString[i];
    switch (c) {
    case '%': {
      formatString.push_back(c);
 
      // Parse the width specifier.
      SmallString<6> width;
      c = origFormatString[++i];
      while (isdigit(c)) {
        width.push_back(c);
        c = origFormatString[++i];
      }
 
      // Parse the radix.
      switch (c) {
      case 'b':
      case 'd':
      case 'x':
        if (!width.empty())
          formatString.append(width);
        [[fallthrough]];
      case 'c':
        substitutions.push_back(substitutionOperands[opIdx++]);
        [[fallthrough]];
      default:
        formatString.push_back(c);
      }
      break;
    }
    case '{':
      if (origFormatString.slice(i, i + 4) == "{{}}") {
        formatString.append("{{");
        TypeSwitch<Operation *>(substitutionOperands[opIdx++].getDefiningOp())
            .Case<TimeOp>(
                [&](auto time) { formatString.append("SimulationTime"); })
            .Case<HierarchicalModuleNameOp>([&](auto time) {
              formatString.append("HierarchicalModuleName");
            })
            .Default([&](auto) {
              emitError(op, "unsupported fstring substitution type");
            });
        formatString.append("}}");
      }
      i += 3;
      break;
    default:
      formatString.push_back(c);
    }
  }
  ps.writeQuotedEscaped(formatString);
}
 
void Emitter::emitStatement(PrintFOp op) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "printf(" << PP::ibox0;
    emitExpression(op.getClock());
    ps << "," << PP::space;
    emitExpression(op.getCond());
    ps << "," << PP::space;
 
    SmallVector<Value, 4> substitutions;
    emitFormatString(op, op.getFormatString(), op.getSubstitutions(),
                     substitutions);
    for (auto operand : substitutions) {
      ps << "," << PP::space;
      emitExpression(operand);
    }
    ps << ")" << PP::end;
    if (!op.getName().empty()) {
      ps << PP::space << ": " << PPExtString(legalize(op.getNameAttr()));
    }
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(FPrintFOp op) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "fprintf(" << PP::ibox0;
    emitExpression(op.getClock());
    ps << "," << PP::space;
    emitExpression(op.getCond());
    ps << "," << PP::space;
 
    SmallVector<Value, 4> outputFileSubstitutions;
    emitFormatString(op, op.getOutputFile(), op.getOutputFileSubstitutions(),
                     outputFileSubstitutions);
    if (!outputFileSubstitutions.empty()) {
      ps << "," << PP::space;
      interleaveComma(outputFileSubstitutions);
    }
 
    ps << "," << PP::space;
    SmallVector<Value, 4> substitutions;
    emitFormatString(op, op.getFormatString(), op.getSubstitutions(),
                     substitutions);
    if (!substitutions.empty()) {
      ps << "," << PP::space;
      interleaveComma(substitutions);
    }
 
    ps << ")" << PP::end;
    if (!op.getName().empty()) {
      ps << PP::space << ": " << PPExtString(legalize(op.getNameAttr()));
    }
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(FFlushOp op) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "fflush(" << PP::ibox0;
    emitExpression(op.getClock());
    ps << "," << PP::space;
    emitExpression(op.getCond());
    if (op.getOutputFileAttr()) {
      ps << "," << PP::space;
      SmallVector<Value, 4> substitutions;
      emitFormatString(op, op.getOutputFileAttr(),
                       op.getOutputFileSubstitutions(), substitutions);
      if (!substitutions.empty()) {
        ps << "," << PP::space;
        interleaveComma(substitutions);
      }
    }
    ps << ")" << PP::end;
  });
  emitLocationAndNewLine(op);
}
 
template <class T>
void Emitter::emitVerifStatement(T op, StringRef mnemonic) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << mnemonic << "(" << PP::ibox0;
    emitExpression(op.getClock());
    ps << "," << PP::space;
    emitExpression(op.getPredicate());
    ps << "," << PP::space;
    emitExpression(op.getEnable());
    ps << "," << PP::space;
    ps.writeQuotedEscaped(op.getMessage());
    ps << ")" << PP::end;
    if (!op.getName().empty()) {
      ps << PP::space << ": " << PPExtString(legalize(op.getNameAttr()));
    }
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(ConnectOp op) {
  startStatement();
  if (FIRVersion(3, 0, 0) <= version) {
    ps.scopedBox(PP::ibox2, [&]() {
      if (op.getSrc().getDefiningOp<InvalidValueOp>()) {
        ps << "invalidate" << PP::space;
        emitExpression(op.getDest());
      } else {
        ps << "connect" << PP::space;
        emitExpression(op.getDest());
        ps << "," << PP::space;
        emitExpression(op.getSrc());
      }
    });
  } else {
    auto emitLHS = [&]() { emitExpression(op.getDest()); };
    if (op.getSrc().getDefiningOp<InvalidValueOp>()) {
      emitAssignLike(
          emitLHS, [&]() { ps << "invalid"; }, PPExtString("is"));
    } else {
      emitAssignLike(
          emitLHS, [&]() { emitExpression(op.getSrc()); }, PPExtString("<="));
    }
  }
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(MatchingConnectOp op) {
  startStatement();
  if (FIRVersion(3, 0, 0) <= version) {
    ps.scopedBox(PP::ibox2, [&]() {
      if (op.getSrc().getDefiningOp<InvalidValueOp>()) {
        ps << "invalidate" << PP::space;
        emitExpression(op.getDest());
      } else {
        ps << "connect" << PP::space;
        emitExpression(op.getDest());
        ps << "," << PP::space;
        emitExpression(op.getSrc());
      }
    });
  } else {
    auto emitLHS = [&]() { emitExpression(op.getDest()); };
    if (op.getSrc().getDefiningOp<InvalidValueOp>()) {
      emitAssignLike(
          emitLHS, [&]() { ps << "invalid"; }, PPExtString("is"));
    } else {
      emitAssignLike(
          emitLHS, [&]() { emitExpression(op.getSrc()); }, PPExtString("<="));
    }
  }
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(PropAssignOp op) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "propassign" << PP::space;
    interleaveComma(op.getOperands());
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(InstanceOp op) {
  startStatement();
  auto legalName = legalize(op.getNameAttr());
  ps << "inst " << PPExtString(legalName) << " of "
     << PPExtString(legalize(op.getModuleNameAttr().getAttr()));
  emitLocationAndNewLine(op);
 
  // Make sure we have a name like `<inst>.<port>` for each of the instance
  // result values.
  SmallString<16> portName(legalName);
  portName.push_back('.');
  unsigned baseLen = portName.size();
  for (unsigned i = 0, e = op.getNumResults(); i < e; ++i) {
    portName.append(legalize(op.getPortName(i)));
    addValueName(op.getResult(i), portName);
    portName.resize(baseLen);
  }
}
 
void Emitter::emitStatement(InstanceChoiceOp op) {
  startStatement();
  auto legalName = legalize(op.getNameAttr());
  ps << "instchoice " << PPExtString(legalName) << " of "
     << PPExtString(legalize(op.getDefaultTargetAttr().getAttr())) << ", "
     << PPExtString(legalize(op.getOptionNameAttr())) << " :";
  emitLocation(op);
  ps.scopedBox(PP::bbox2, [&] {
    for (const auto &[optSym, targetSym] : op.getTargetChoices()) {
      ps << PP::newline;
      ps << PPExtString(legalize(optSym.getLeafReference()));
      ps << " => ";
      ps << PPExtString(legalize(targetSym.getAttr()));
    }
  });
  setPendingNewline();
 
  SmallString<16> portName(legalName);
  portName.push_back('.');
  unsigned baseLen = portName.size();
  for (unsigned i = 0, e = op.getNumResults(); i < e; ++i) {
    portName.append(legalize(op.getPortName(i)));
    addValueName(op.getResult(i), portName);
    portName.resize(baseLen);
  }
}
 
void Emitter::emitStatement(AttachOp op) {
  emitStatementFunctionOp(PPExtString("attach"), op);
}
 
void Emitter::emitStatement(MemOp op) {
  auto legalName = legalize(op.getNameAttr());
  SmallString<16> portName(legalName);
  portName.push_back('.');
  auto portNameBaseLen = portName.size();
  for (auto result : llvm::zip(op.getResults(), op.getPortNames())) {
    portName.resize(portNameBaseLen);
    portName.append(legalize(cast<StringAttr>(std::get<1>(result))));
    addValueName(std::get<0>(result), portName);
  }
 
  startStatement();
  ps << "mem " << PPExtString(legalName) << " :";
  emitLocationAndNewLine(op);
  ps.scopedBox(PP::bbox2, [&]() {
    startStatement();
    ps << "data-type => ";
    emitType(op.getDataType());
    ps << PP::newline;
    ps << "depth => ";
    ps.addAsString(op.getDepth());
    ps << PP::newline;
    ps << "read-latency => ";
    ps.addAsString(op.getReadLatency());
    ps << PP::newline;
    ps << "write-latency => ";
    ps.addAsString(op.getWriteLatency());
    ps << PP::newline;
 
    SmallString<16> reader, writer, readwriter;
    for (std::pair<StringAttr, MemOp::PortKind> port : op.getPorts()) {
      auto add = [&](SmallString<16> &to, StringAttr name) {
        if (!to.empty())
          to.push_back(' ');
        to.append(name.getValue());
      };
      switch (port.second) {
      case MemOp::PortKind::Read:
        add(reader, legalize(port.first));
        break;
      case MemOp::PortKind::Write:
        add(writer, legalize(port.first));
        break;
      case MemOp::PortKind::ReadWrite:
        add(readwriter, legalize(port.first));
        break;
      case MemOp::PortKind::Debug:
        emitOpError(op, "has unsupported 'debug' port");
        return;
      }
    }
    if (!reader.empty())
      ps << "reader => " << reader << PP::newline;
    if (!writer.empty())
      ps << "writer => " << writer << PP::newline;
    if (!readwriter.empty())
      ps << "readwriter => " << readwriter << PP::newline;
 
    ps << "read-under-write => ";
    emitAttribute(op.getRuwAttr());
    setPendingNewline();
  });
}
 
void Emitter::emitStatement(SeqMemOp op) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "smem " << PPExtString(legalize(op.getNameAttr()));
    emitTypeWithColon(op.getType());
    ps << "," << PP::space;
    emitAttribute(op.getRuwAttr());
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(CombMemOp op) {
  startStatement();
  ps.scopedBox(PP::ibox2, [&]() {
    ps << "cmem " << PPExtString(legalize(op.getNameAttr()));
    emitTypeWithColon(op.getType());
  });
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(MemoryPortOp op) {
  // Nothing to output for this operation.
  addValueName(op.getData(), legalize(op.getNameAttr()));
}
 
void Emitter::emitStatement(MemoryDebugPortOp op) {
  // Nothing to output for this operation.
  addValueName(op.getData(), legalize(op.getNameAttr()));
}
 
void Emitter::emitStatement(MemoryPortAccessOp op) {
  startStatement();
 
  // Print the port direction and name.
  auto port = cast<MemoryPortOp>(op.getPort().getDefiningOp());
  emitAttribute(port.getDirection());
  // TODO: emitAssignLike
  ps << " mport " << PPExtString(legalize(port.getNameAttr())) << " = ";
 
  // Print the memory name.
  auto *mem = port.getMemory().getDefiningOp();
  if (auto seqMem = dyn_cast<SeqMemOp>(mem))
    ps << legalize(seqMem.getNameAttr());
  else
    ps << legalize(cast<CombMemOp>(mem).getNameAttr());
 
  // Print the address.
  ps << "[";
  emitExpression(op.getIndex());
  ps << "], ";
 
  // Print the clock.
  emitExpression(op.getClock());
 
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(RefDefineOp op) {
  startStatement();
  emitAssignLike([&]() { emitExpression(op.getDest()); },
                 [&]() { emitExpression(op.getSrc()); }, PPExtString("="),
                 PPExtString("define"));
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(RefForceOp op) {
  emitStatementFunctionOp(PPExtString("force"), op);
}
 
void Emitter::emitStatement(RefForceInitialOp op) {
  startStatement();
  auto constantPredicate =
      dyn_cast_or_null<ConstantOp>(op.getPredicate().getDefiningOp());
  bool hasEnable = !constantPredicate || constantPredicate.getValue() == 0;
  if (hasEnable) {
    ps << "when ";
    emitExpression(op.getPredicate());
    ps << ":" << PP::bbox2 << PP::neverbreak << PP::newline;
  }
  ps << "force_initial(";
  ps.scopedBox(PP::ibox0, [&]() {
    interleaveComma({op.getDest(), op.getSrc()});
    ps << ")";
  });
  if (hasEnable)
    ps << PP::end;
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(RefReleaseOp op) {
  emitStatementFunctionOp(PPExtString("release"), op);
}
 
void Emitter::emitStatement(RefReleaseInitialOp op) {
  startStatement();
  auto constantPredicate =
      dyn_cast_or_null<ConstantOp>(op.getPredicate().getDefiningOp());
  bool hasEnable = !constantPredicate || constantPredicate.getValue() == 0;
  if (hasEnable) {
    ps << "when ";
    emitExpression(op.getPredicate());
    ps << ":" << PP::bbox2 << PP::neverbreak << PP::newline;
  }
  ps << "release_initial(";
  emitExpression(op.getDest());
  ps << ")";
  if (hasEnable)
    ps << PP::end;
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(LayerBlockOp op) {
  startStatement();
  ps << "layerblock " << op.getLayerName().getLeafReference() << " :";
  emitLocationAndNewLine(op);
  auto *body = op.getBody();
  ps.scopedBox(PP::bbox2, [&]() { emitStatementsInBlock(*body); });
}
 
void Emitter::emitStatement(InvalidValueOp op) {
  // Only emit this invalid value if it is used somewhere else than the RHS of
  // a connect.
  if (llvm::all_of(op->getUses(), [&](OpOperand &use) {
        return use.getOperandNumber() == 1 &&
               isa<ConnectOp, MatchingConnectOp>(use.getOwner());
      }))
    return;
 
  // TODO: emitAssignLike ?
  startStatement();
  auto name = circuitNamespace.newName("_invalid");
  addValueName(op, name);
  ps << "wire " << PPExtString(name) << " : ";
  emitType(op.getType());
  emitLocationAndNewLine(op);
  startStatement();
  if (FIRVersion(3, 0, 0) <= version)
    ps << "invalidate " << PPExtString(name);
  else
    ps << PPExtString(name) << " is invalid";
  emitLocationAndNewLine(op);
}
 
void Emitter::emitStatement(GenericIntrinsicOp op) {
  startStatement();
  if (op.use_empty())
    emitGenericIntrinsic(op);
  else {
    assert(!isEmittedInline(op));
    auto name = circuitNamespace.newName("_gen_int");
    addValueName(op.getResult(), name);
    emitAssignLike([&]() { ps << "node " << PPExtString(name); },
                   [&]() { emitGenericIntrinsic(op); });
  }
  emitLocationAndNewLine(op);
}
 
void Emitter::emitExpression(Value value) {
  // Handle the trivial case where we already have a name for this value which
  // we can use.
  if (auto name = lookupEmittedName(value)) {
    // Don't use PPExtString here, can't trust valueNames storage, cleared.
    ps << *name;
    return;
  }
 
  auto op = value.getDefiningOp();
  assert(op && "value must either be a block arg or the result of an op");
  TypeSwitch<Operation *>(op)
      .Case<
          // Basic expressions
          ConstantOp, SpecialConstantOp, SubfieldOp, SubindexOp, SubaccessOp,
          OpenSubfieldOp, OpenSubindexOp,
          // Binary
          AddPrimOp, SubPrimOp, MulPrimOp, DivPrimOp, RemPrimOp, AndPrimOp,
          OrPrimOp, XorPrimOp, LEQPrimOp, LTPrimOp, GEQPrimOp, GTPrimOp,
          EQPrimOp, NEQPrimOp, DShlPrimOp, DShlwPrimOp, DShrPrimOp,
          // Unary
          AsSIntPrimOp, AsUIntPrimOp, AsAsyncResetPrimOp, AsClockPrimOp,
          CvtPrimOp, NegPrimOp, NotPrimOp, AndRPrimOp, OrRPrimOp, XorRPrimOp,
          // Miscellaneous
          BitsPrimOp, HeadPrimOp, TailPrimOp, PadPrimOp, MuxPrimOp, ShlPrimOp,
          ShrPrimOp, UninferredResetCastOp, ConstCastOp, StringConstantOp,
          FIntegerConstantOp, BoolConstantOp, DoubleConstantOp, ListCreateOp,
          UnresolvedPathOp, GenericIntrinsicOp, CatPrimOp, UnsafeDomainCastOp,
          // Reference expressions
          RefSendOp, RefResolveOp, RefSubOp, RWProbeOp, RefCastOp,
          // Format String expressions
          TimeOp>([&](auto op) {
        ps.scopedBox(PP::ibox0, [&]() { emitExpression(op); });
      })
      .Default([&](auto op) {
        emitOpError(op, "not supported as expression");
        ps << "<unsupported-expr-" << PPExtString(op->getName().stripDialect())
           << ">";
      });
}
 
void Emitter::emitExpression(ConstantOp op) {
  // Don't include 'const' on the type in a literal expression
  emitType(op.getType(), false);
  // TODO: Add option to control base-2/8/10/16 output here.
  ps << "(";
  ps.addAsString(op.getValue());
  ps << ")";
}
 
void Emitter::emitExpression(SpecialConstantOp op) {
  auto emitInner = [&]() {
    ps << "UInt<1>(";
    ps.addAsString(op.getValue());
    ps << ")";
  };
  // TODO: Emit type decl for type alias.
  FIRRTLTypeSwitch<FIRRTLType>(type_cast<FIRRTLType>(op.getType()))
      .Case<ClockType>([&](auto type) {
        ps << "asClock(";
        emitInner();
        ps << ")";
      })
      .Case<ResetType>([&](auto type) { emitInner(); })
      .Case<AsyncResetType>([&](auto type) {
        ps << "asAsyncReset(";
        emitInner();
        ps << ")";
      });
}
 
// NOLINTNEXTLINE(misc-no-recursion)
void Emitter::emitExpression(SubfieldOp op) {
  BundleType type = op.getInput().getType();
  emitExpression(op.getInput());
  ps << "." << legalize(type.getElementNameAttr(op.getFieldIndex()));
}
 
// NOLINTNEXTLINE(misc-no-recursion)
void Emitter::emitExpression(SubindexOp op) {
  emitExpression(op.getInput());
  ps << "[";
  ps.addAsString(op.getIndex());
  ps << "]";
}
 
// NOLINTNEXTLINE(misc-no-recursion)
void Emitter::emitExpression(SubaccessOp op) {
  emitExpression(op.getInput());
  ps << "[";
  emitExpression(op.getIndex());
  ps << "]";
}
 
void Emitter::emitExpression(OpenSubfieldOp op) {
  auto type = op.getInput().getType();
  emitExpression(op.getInput());
  ps << "." << legalize(type.getElementNameAttr(op.getFieldIndex()));
}
 
void Emitter::emitExpression(OpenSubindexOp op) {
  emitExpression(op.getInput());
  ps << "[";
  ps.addAsString(op.getIndex());
  ps << "]";
}
 
void Emitter::emitExpression(RefSendOp op) {
  ps << "probe(";
  emitExpression(op.getBase());
  ps << ")";
}
 
void Emitter::emitExpression(RefResolveOp op) {
  ps << "read(";
  emitExpression(op.getRef());
  ps << ")";
}
 
void Emitter::emitExpression(RefSubOp op) {
  emitExpression(op.getInput());
  FIRRTLTypeSwitch<FIRRTLBaseType, void>(op.getInput().getType().getType())
      .Case<FVectorType>([&](auto type) {
        ps << "[";
        ps.addAsString(op.getIndex());
        ps << "]";
      })
      .Case<BundleType>(
          [&](auto type) { ps << "." << type.getElementName(op.getIndex()); });
}
 
void Emitter::emitExpression(RWProbeOp op) {
  ps << "rwprobe(";
 
  // Find the probe target.
  auto target = symInfos->get().irn.lookup(op.getTarget());
  Value base;
  if (target.isPort()) {
    auto mod = cast<FModuleOp>(target.getOp());
    auto port = target.getPort();
    base = mod.getArgument(port);
  } else
    base = cast<hw::InnerSymbolOpInterface>(target.getOp()).getTargetResult();
 
  // Print target.  Needs this to have a name already.
  emitExpression(base);
 
  // Print indexing for the target field.
  auto fieldID = target.getField();
  auto type = base.getType();
  while (fieldID) {
    FIRRTLTypeSwitch<Type, void>(type)
        .Case<FVectorType, OpenVectorType>([&](auto vecTy) {
          auto index = vecTy.getIndexForFieldID(fieldID);
          ps << "[";
          ps.addAsString(index);
          ps << "]";
          auto [subtype, subfieldID] = vecTy.getSubTypeByFieldID(fieldID);
          type = subtype;
          fieldID = subfieldID;
        })
        .Case<BundleType, OpenBundleType>([&](auto bundleTy) {
          auto index = bundleTy.getIndexForFieldID(fieldID);
          ps << "." << bundleTy.getElementName(index);
          auto [subtype, subfieldID] = bundleTy.getSubTypeByFieldID(fieldID);
          type = subtype;
          fieldID = subfieldID;
        });
  }
  ps << ")";
}
 
void Emitter::emitExpression(RefCastOp op) { emitExpression(op.getInput()); }
 
void Emitter::emitExpression(UninferredResetCastOp op) {
  emitExpression(op.getInput());
}
 
void Emitter::emitExpression(FIntegerConstantOp op) {
  ps << "Integer(";
  ps.addAsString(op.getValue());
  ps << ")";
}
 
void Emitter::emitExpression(BoolConstantOp op) {
  ps << "Bool(" << (op.getValue() ? "true" : "false") << ")";
}
 
void Emitter::emitExpression(DoubleConstantOp op) {
  ps << "Double(";
  // Use APFloat::toString.
  // Printing as double is not what we want,
  // and this at least handles the basic cases in a way
  // that will round-trip.
  SmallString<16> str;
  op.getValueAttr().getValue().toString(str);
  ps << str;
  ps << ")";
}
 
void Emitter::emitExpression(StringConstantOp op) {
  ps << "String(";
  ps.writeQuotedEscaped(op.getValue());
  ps << ")";
}
 
void Emitter::emitExpression(ListCreateOp op) {
  return emitLiteralExpression(op.getType(), op.getElements());
}
 
void Emitter::emitExpression(UnresolvedPathOp op) {
  ps << "path(";
  ps.writeQuotedEscaped(op.getTarget());
  ps << ")";
}
 
void Emitter::emitExpression(GenericIntrinsicOp op) {
  emitGenericIntrinsic(op);
}
 
void Emitter::emitExpression(ConstCastOp op) { emitExpression(op.getInput()); }
 
void Emitter::emitPrimExpr(StringRef mnemonic, Operation *op,
                           ArrayRef<uint32_t> attrs) {
  ps << mnemonic << "(" << PP::ibox0;
  interleaveComma(op->getOperands());
  if (!op->getOperands().empty() && !attrs.empty())
    ps << "," << PP::space;
  interleaveComma(attrs, [&](auto attr) { ps.addAsString(attr); });
  ps << ")" << PP::end;
}
 
void Emitter::emitExpression(CatPrimOp op) {
  size_t numOperands = op.getNumOperands();
  switch (numOperands) {
  case 0:
    // Emit "UInt<0>(0)"
    emitType(op.getType(), false);
    ps << "(0)";
    return;
  case 1: {
    auto operand = op->getOperand(0);
    // If there is no sign conversion, just emit the operand.
    if (isa<UIntType>(operand.getType()))
      return emitExpression(operand);
 
    // Emit cat to convert sign.
    ps << "cat(" << PP::ibox0;
    emitExpression(op->getOperand(0));
    ps << "," << PP::space << "SInt<0>(0))" << PP::end;
    return;
  }
 
  default:
    // Construct a linear tree of cats.
    for (size_t i = 0; i < numOperands - 1; ++i) {
      ps << "cat(" << PP::ibox0;
      emitExpression(op->getOperand(i));
      ps << "," << PP::space;
    }
 
    emitExpression(op->getOperand(numOperands - 1));
    for (size_t i = 0; i < numOperands - 1; ++i)
      ps << ")" << PP::end;
    return;
  }
}
 
void Emitter::emitExpression(UnsafeDomainCastOp op) {
  ps << "unsafe_domain_cast(" << PP::ibox0;
  interleaveComma(op.getOperands(),
                  [&](Value operand) { emitExpression(operand); });
  ps << ")" << PP::end;
}
 
void Emitter::emitAttribute(MemDirAttr attr) {
  switch (attr) {
  case MemDirAttr::Infer:
    ps << "infer";
    break;
  case MemDirAttr::Read:
    ps << "read";
    break;
  case MemDirAttr::Write:
    ps << "write";
    break;
  case MemDirAttr::ReadWrite:
    ps << "rdwr";
    break;
  }
}
 
void Emitter::emitAttribute(RUWBehaviorAttr attr) {
  switch (attr.getValue()) {
  case RUWBehavior::Undefined:
    ps << "undefined";
    break;
  case RUWBehavior::Old:
    ps << "old";
    break;
  case RUWBehavior::New:
    ps << "new";
    break;
  }
}
 
/// Emit a FIRRTL type into the output.
void Emitter::emitType(Type type, bool includeConst) {
  if (includeConst && isConst(type))
    ps << "const ";
  auto emitWidth = [&](std::optional<int32_t> width) {
    if (width) {
      ps << "<";
      ps.addAsString(*width);
      ps << ">";
    }
  };
  // TODO: Emit type decl for type alias.
  FIRRTLTypeSwitch<Type>(type)
      .Case<ClockType>([&](auto) { ps << "Clock"; })
      .Case<ResetType>([&](auto) { ps << "Reset"; })
      .Case<AsyncResetType>([&](auto) { ps << "AsyncReset"; })
      .Case<UIntType>([&](auto type) {
        ps << "UInt";
        emitWidth(type.getWidth());
      })
      .Case<SIntType>([&](auto type) {
        ps << "SInt";
        emitWidth(type.getWidth());
      })
      .Case<AnalogType>([&](auto type) {
        ps << "Analog";
        emitWidth(type.getWidth());
      })
      .Case<OpenBundleType, BundleType>([&](auto type) {
        ps << "{";
        if (!type.getElements().empty())
          ps << PP::nbsp;
        bool anyEmitted = false;
        ps.scopedBox(PP::cbox0, [&]() {
          for (auto &element : type.getElements()) {
            if (anyEmitted)
              ps << "," << PP::space;
            ps.scopedBox(PP::ibox2, [&]() {
              if (element.isFlip)
                ps << "flip ";
              ps << legalize(element.name);
              emitTypeWithColon(element.type);
              anyEmitted = true;
            });
          }
          if (anyEmitted)
            ps << PP::nbsp;
          ps << "}";
        });
      })
      .Case<OpenVectorType, FVectorType, CMemoryType>([&](auto type) {
        emitType(type.getElementType());
        ps << "[";
        ps.addAsString(type.getNumElements());
        ps << "]";
      })
      .Case<RefType>([&](RefType type) {
        if (type.getForceable())
          ps << "RW";
        ps << "Probe<";
        ps.cbox(2, IndentStyle::Block);
        ps.zerobreak();
        emitType(type.getType());
        if (auto layer = type.getLayer()) {
          ps << ",";
          ps.space();
          emitSymbol(type.getLayer());
        }
        ps << BreakToken(0, -2) << ">";
        ps.end();
      })
      .Case<AnyRefType>([&](AnyRefType type) { ps << "AnyRef"; })
      .Case<StringType>([&](StringType type) { ps << "String"; })
      .Case<FIntegerType>([&](FIntegerType type) { ps << "Integer"; })
      .Case<BoolType>([&](BoolType type) { ps << "Bool"; })
      .Case<DoubleType>([&](DoubleType type) { ps << "Double"; })
      .Case<PathType>([&](PathType type) { ps << "Path"; })
      .Case<ListType>([&](ListType type) {
        ps << "List<";
        emitType(type.getElementType());
        ps << ">";
      })
      .Case<DomainType>([&](DomainType type) { ps << "Domain"; })
      .Default([&](auto type) {
        llvm_unreachable("all types should be implemented");
      });
}
 
void Emitter::emitDomains(Attribute attr,
                          const DenseMap<size_t, StringRef> &domainMap) {
  if (!attr)
    return;
  if (auto domains = dyn_cast<ArrayAttr>(attr)) {
    if (domains.empty())
      return;
    ps << " domains [";
    ps.scopedBox(PP::ibox0, [&]() {
      interleaveComma(domains, [&](Attribute attr) {
        auto itr = domainMap.find(cast<IntegerAttr>(attr).getUInt());
        assert(itr != domainMap.end() && "Unable to find domain");
        ps.addAsString(itr->second);
      });
      ps << "]";
    });
  } else {
    auto kind = cast<FlatSymbolRefAttr>(attr);
    ps << " of " << PPExtString(kind.getValue());
  }
}
 
/// Emit a location as `@[<filename> <line>:<column>]` annotation, including a
/// leading space.
void Emitter::emitLocation(Location loc) {
  // TODO: Handle FusedLoc and uniquify locations, avoid repeated file names.
  ps << PP::neverbreak;
  if (auto fileLoc =
          dyn_cast_or_null<FileLineColLoc, LocationAttr>(LocationAttr(loc))) {
    ps << " @[" << fileLoc.getFilename().getValue();
    if (auto line = fileLoc.getLine()) {
      ps << " ";
      ps.addAsString(line);
      if (auto col = fileLoc.getColumn()) {
        ps << ":";
        ps.addAsString(col);
      }
    }
    ps << "]";
  }
}
// NOLINTEND(misc-no-recursion)
 
//===----------------------------------------------------------------------===//
// Driver
//===----------------------------------------------------------------------===//
 
// Emit the specified FIRRTL circuit into the given output stream.
mlir::LogicalResult
circt::firrtl::exportFIRFile(mlir::ModuleOp module, llvm::raw_ostream &os,
                             std::optional<size_t> targetLineLength,
                             FIRVersion version) {
  Emitter emitter(os, version,
                  targetLineLength.value_or(defaultTargetLineLength));
  for (auto &op : *module.getBody()) {
    if (auto circuitOp = dyn_cast<CircuitOp>(op))
      emitter.emitCircuit(circuitOp);
  }
  return emitter.finalize();
}
 
void circt::firrtl::registerToFIRFileTranslation() {
  static llvm::cl::opt<size_t> targetLineLength(
      "target-line-length",
      llvm::cl::desc("Target line length for emitted .fir"),
      llvm::cl::value_desc("number of chars"),
      llvm::cl::init(defaultTargetLineLength));
  static mlir::TranslateFromMLIRRegistration toFIR(
      "export-firrtl", "emit FIRRTL dialect operations to .fir output",
      [](ModuleOp module, llvm::raw_ostream &os) {
        return exportFIRFile(module, os, targetLineLength, exportFIRVersion);
      },
      [](mlir::DialectRegistry &registry) {
        registry.insert<chirrtl::CHIRRTLDialect>();
        registry.insert<firrtl::FIRRTLDialect>();
      });
}