OpenSTA/liberty/LinearModel.cc

131 lines
3.2 KiB
C++

// OpenSTA, Static Timing Analyzer
// Copyright (c) 2025, 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.
#include "LinearModel.hh"
#include "Units.hh"
#include "Liberty.hh"
namespace sta {
using std::string;
GateLinearModel::GateLinearModel(LibertyCell *cell,
float intrinsic,
float resistance) :
GateTimingModel(cell),
intrinsic_(intrinsic),
resistance_(resistance)
{
}
void
GateLinearModel::gateDelay(const Pvt *,
float,
float load_cap,
bool,
// return values
ArcDelay &gate_delay,
Slew &drvr_slew) const
{
gate_delay = intrinsic_ + resistance_ * load_cap;
drvr_slew = 0.0;
}
string
GateLinearModel::reportGateDelay(const Pvt *,
float,
float load_cap,
bool,
int digits) const
{
const LibertyLibrary *library = cell_->libertyLibrary();
const Units *units = library->units();
const Unit *time_unit = units->timeUnit();
const Unit *res_unit = units->resistanceUnit();
const Unit *cap_unit = units->capacitanceUnit();
string result = "Delay = ";
result += time_unit->asString(intrinsic_, digits);
result += " + ";
result += res_unit->asString(resistance_, digits);
result += " * ";
result += cap_unit->asString(load_cap, digits);
result += " = ";
float delay = intrinsic_ + resistance_ * load_cap;
result += time_unit->asString(delay, digits);
return result;
}
float
GateLinearModel::driveResistance(const Pvt *) const
{
return resistance_;
}
void
GateLinearModel::setIsScaled(bool)
{
}
CheckLinearModel::CheckLinearModel(LibertyCell *cell,
float intrinsic) :
CheckTimingModel(cell),
intrinsic_(intrinsic)
{
}
ArcDelay
CheckLinearModel::checkDelay(const Pvt *,
float,
float,
float,
bool) const
{
return intrinsic_;
}
string
CheckLinearModel::reportCheckDelay(const Pvt *,
float,
const char *,
float,
float,
bool,
int digits) const
{
const LibertyLibrary *library = cell_->libertyLibrary();
const Units *units = library->units();
const Unit *time_unit = units->timeUnit();
string result = "Check = ";
result += time_unit->asString(intrinsic_, digits);
return result;
}
void
CheckLinearModel::setIsScaled(bool)
{
}
} // namespace