OpenSTA/search/Latches.hh

108 lines
3.4 KiB
C++

// OpenSTA, Static Timing Analyzer
// Copyright (c) 2024, 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/>.
#pragma once
#include "GraphClass.hh"
#include "SearchClass.hh"
#include "SdcClass.hh"
#include "StaState.hh"
namespace sta {
enum class LatchEnableState { enabled, open, closed };
// Latches class defines latch behavior.
class Latches : public StaState
{
public:
Latches(StaState *sta);
void latchTimeGivenToStartpoint(Path *d_path,
Path *q_path,
Edge *d_q_edge,
// Return values.
Arrival &time_given,
PathVertex &enable_path);
void latchRequired(const Path *data_path,
const PathVertex *enable_path,
const PathVertex *disable_path,
MultiCyclePath *mcp,
PathDelay *path_delay,
Arrival src_clk_latency,
const ArcDelay &margin,
// Return values.
Required &required,
Delay &borrow,
Arrival &adjusted_data_arrival,
Delay &time_given_to_startpoint);
void latchRequired(const Path *data_path,
const PathVertex *enable_path,
const PathVertex *disable_path,
const PathAnalysisPt *path_ap,
// Return values.
Required &required,
Delay &borrow,
Arrival &adjusted_data_arrival,
Delay &time_given_to_startpoint);
void latchBorrowInfo(const Path *data_path,
const PathVertex *enable_path,
const PathVertex *disable_path,
const ArcDelay &margin,
bool ignore_clk_latency,
// Return values.
float &nom_pulse_width,
Delay &open_latency,
Delay &latency_diff,
float &open_uncertainty,
Crpr &open_crpr,
Crpr &crpr_diff,
Delay &max_borrow,
bool &borrow_limit_exists);
bool isLatchDtoQ(Edge *edge) const;
// Find the latch EN->Q edge for a D->Q edge.
void latchDtoQEnable(Edge *d_q_edge,
const Instance *inst,
// Return values.
Vertex *&enable_vertex,
const RiseFall *&enable_rf,
LatchEnableState &state) const;
LatchEnableState latchDtoQState(Edge *d_q_edge) const;
void latchEnableOtherPath(Path *path,
const PathAnalysisPt *tgt_clk_path_ap,
// Return value.
PathVertex &other_path);
void latchEnablePath(Path *q_path, Edge *d_q_edge,
// Return value.
PathVertex &enable_path) const;
void latchOutArrival(Path *data_path,
TimingArc *d_q_arc,
Edge *d_q_edge,
const PathAnalysisPt *path_ap,
Tag *&q_tag,
ArcDelay &arc_delay,
Arrival &q_arrival);
protected:
ArcDelay latchSetupMargin(Vertex *data_vertex,
const RiseFall *data_rf,
const Path *disable_path,
const PathAnalysisPt *path_ap);
ExceptionPath *exceptionTo(Path *data_path,
const ClockEdge *en_clk_edge);
};
} // namespace