The-OpenROAD-Project_OpenSTA/dcalc/UnitDelayCalc.hh

// OpenSTA, Static Timing Analyzer
// Copyright (c) 2026, Parallax Software, Inc.
// 
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// 
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// 
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://www.gnu.org/licenses/>.
// 
// The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software.
// 
// Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 
// This notice may not be removed or altered from any source distribution.

#pragma once

#include "ArcDelayCalc.hh"

namespace sta {

// Unit delay calculator.
class UnitDelayCalc : public ArcDelayCalc
{
public:
  UnitDelayCalc(StaState *sta);
  ArcDelayCalc *copy() override;
  std::string_view name() const override { return "unit"; }
  Parasitic *findParasitic(const Pin *drvr_pin,
                           const RiseFall *rf,
                           const Scene *scene,
                           const MinMax *min_max) override;
  bool reduceSupported() const override { return false; }
  Parasitic *reduceParasitic(const Parasitic *parasitic_network,
                             const Pin *drvr_pin,
                             const RiseFall *rf,
                             const Scene *scene,
                             const MinMax *min_max) override;
  void reduceParasitic(const Parasitic *parasitic_network,
                       const Net *net,
                       const Scene *scene,
                       const MinMaxAll *min_max) override;
  void setDcalcArgParasiticSlew(ArcDcalcArg &gate,
                                const Scene *scene,
                                const MinMax *min_max) override;
  void setDcalcArgParasiticSlew(ArcDcalcArgSeq &gates,
                                const Scene *scene,
                                const MinMax *min_max) override;
  ArcDcalcResult inputPortDelay(const Pin *port_pin,
                                float in_slew,
                                const RiseFall *rf,
                                const Parasitic *parasitic,
                                const LoadPinIndexMap &load_pin_index_map,
                                const Scene *scene,
                const MinMax *min_max) override;
  ArcDcalcResult gateDelay(const Pin *drvr_pin,
                           const TimingArc *arc,
                           const Slew &in_slew,
                           // Pass in load_cap or parasitic.
                           float load_cap,
                           const Parasitic *parasitic,
                           const LoadPinIndexMap &load_pin_index_map,
                           const Scene *scene,
                           const MinMax *min_max) override;
  ArcDcalcResultSeq gateDelays(ArcDcalcArgSeq &args,
                               const LoadPinIndexMap &load_pin_index_map,
                               const Scene *scene,
                               const MinMax *min_max) override;
  ArcDelay checkDelay(const Pin *check_pin,
                      const TimingArc *arc,
                      const Slew &from_slew,
                      const Slew &to_slew,
                      float related_out_cap,
                      const Scene *scene,
                      const MinMax *min_max) override;
  std::string reportGateDelay(const Pin *drvr_pin,
                              const TimingArc *arc,
                              const Slew &in_slew,
                              float load_cap,
                              const Parasitic *parasitic,
                              const LoadPinIndexMap &load_pin_index_map,
                              const Scene *scene,
                              const MinMax *min_max,
                              int digits) override;
  std::string reportCheckDelay(const Pin *check_pin,
                               const TimingArc *arc,
                               const Slew &from_slew,
                               std::string_view from_slew_annotation,
                               const Slew &to_slew,
                               float related_out_cap,
                               const Scene *scene,
                               const MinMax *min_max,
                               int digits) override;
  void finishDrvrPin() override;

protected:
  ArcDcalcResult unitDelayResult(const LoadPinIndexMap &load_pin_index_map);
};

ArcDelayCalc *
makeUnitDelayCalc(StaState *sta);

} // namespace sta