Trace.h

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//===- Trace.h - Simulation trace definition --------------------*- 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 file defines the Trace class, used to handle the signal trace generation
// for the llhd-sim tool.
//
//===----------------------------------------------------------------------===//
 
#ifndef CIRCT_DIALECT_LLHD_SIMULATOR_TRACE_H
#define CIRCT_DIALECT_LLHD_SIMULATOR_TRACE_H
 
#include "State.h"
 
#include <map>
#include <vector>
 
namespace llvm {
class raw_ostream;
} // namespace llvm
 
namespace circt {
namespace llhd {
namespace sim {
 
enum class TraceMode { Full, Reduced, Merged, MergedReduce, NamedOnly, None };
 
class Trace {
  llvm::raw_ostream &out;
  std::unique_ptr<State> const &state;
  TraceMode mode;
  Time currentTime;
  // Each entry defines if the respective signal is active for tracing.
  std::vector<bool> isTraced;
  // Buffer of changes ready to be flushed.
  std::vector<std::pair<std::string, std::string>> changes;
  // Buffer of changes for the merged formats.
  std::map<std::pair<unsigned, int>, std::string> mergedChanges;
  // Buffer of last dumped change for each signal.
  std::map<std::pair<std::string, int>, std::string> lastValue;
 
  /// Push one change to the changes vector.
  void pushChange(unsigned inst, unsigned sigIndex, int elem);
  /// Push one change for each element of a signal if it is of a structured
  /// type, or the full signal otherwise.
  void pushAllChanges(unsigned inst, unsigned sigIndex);
 
  /// Add a merged change to the change buffer.
  void addChangeMerged(unsigned);
 
  /// Sorts the changes buffer lexicographically wrt. the hierarchical paths.
  void sortChanges();
 
  /// Flush the changes buffer to the output stream with full format.
  void flushFull();
  // Flush the changes buffer to the output stream with merged format.
  void flushMerged();
 
public:
  Trace(std::unique_ptr<State> const &state, llvm::raw_ostream &out,
        TraceMode mode);
 
  /// Add a value change to the trace changes buffer.
  void addChange(unsigned);
 
  /// Flush the changes buffer to the output stream. The flush can be forced for
  /// merged changes, flushing even if the next real-time step has not been
  /// reached.
  void flush(bool force = false);
};
} // namespace sim
} // namespace llhd
} // namespace circt
 
#endif // CIRCT_DIALECT_LLHD_SIMULATOR_TRACE_H