OpenSTA/search/ClkLatency.cc

318 lines
11 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 "ClkLatency.hh"
#include <algorithm>
#include "Report.hh"
#include "Debug.hh"
#include "Units.hh"
#include "Liberty.hh"
#include "Network.hh"
#include "Clock.hh"
#include "Graph.hh"
#include "Path.hh"
#include "StaState.hh"
#include "Search.hh"
#include "PathAnalysisPt.hh"
#include "ClkInfo.hh"
namespace sta {
ClkLatency::ClkLatency(StaState *sta) :
StaState(sta)
{
}
ClkDelays
ClkLatency::findClkDelays(const Clock *clk,
const Corner *corner,
bool include_internal_latency)
{
ConstClockSeq clks;
clks.push_back(clk);
ClkDelayMap clk_delay_map = findClkDelays(clks, corner,
include_internal_latency);
return clk_delay_map[clk];
}
void
ClkLatency::reportClkLatency(ConstClockSeq &clks,
const Corner *corner,
bool include_internal_latency,
int digits)
{
ClkDelayMap clk_delay_map = findClkDelays(clks, corner, include_internal_latency);
// Sort the clocks to report in a stable order.
ConstClockSeq sorted_clks;
for (const Clock *clk : clks)
sorted_clks.push_back(clk);
std::sort(sorted_clks.begin(), sorted_clks.end(), ClkNameLess());
for (const Clock *clk : sorted_clks) {
ClkDelays clk_delays = clk_delay_map[clk];
reportClkLatency(clk, clk_delays, digits);
report_->reportBlankLine();
}
}
void
ClkLatency::reportClkLatency(const Clock *clk,
ClkDelays &clk_delays,
int digits)
{
Unit *time_unit = units_->timeUnit();
report_->reportLine("Clock %s", clk->name());
for (const RiseFall *src_rf : RiseFall::range()) {
for (const RiseFall *end_rf : RiseFall::range()) {
Path path_min;
Delay insertion_min;
Delay delay_min;
float internal_latency_min;
Delay latency_min;
bool exists_min;
clk_delays.delay(src_rf, end_rf, MinMax::min(), insertion_min,
delay_min, internal_latency_min, latency_min,
path_min, exists_min);
Path path_max;
Delay insertion_max;
Delay delay_max;
float internal_latency_max;
Delay latency_max;
bool exists_max;
clk_delays.delay(src_rf, end_rf, MinMax::max(), insertion_max,
delay_max, internal_latency_max, latency_max,
path_max, exists_max);
if (exists_min & exists_max) {
report_->reportLine("%s -> %s",
src_rf->name(),
end_rf->name());
report_->reportLine(" min max");
report_->reportLine("%7s %7s source latency",
delayAsString(insertion_min, this, digits),
delayAsString(insertion_max, this, digits));
report_->reportLine("%7s %7s network latency %s",
delayAsString(delay_min, this, digits),
"",
sdc_network_->pathName(path_min.pin(this)));
report_->reportLine("%7s %7s network latency %s",
"",
delayAsString(delay_max, this, digits),
sdc_network_->pathName(path_max.pin(this)));
if (internal_latency_min != 0.0
|| internal_latency_max != 0.0)
report_->reportLine("%7s %7s internal clock latency",
time_unit->asString(internal_latency_min, digits),
time_unit->asString(internal_latency_max, digits));
report_->reportLine("---------------");
report_->reportLine("%7s %7s latency",
delayAsString(latency_min, this, digits),
delayAsString(latency_max, this, digits));
Delay skew = latency_max - latency_min;
report_->reportLine(" %7s skew",
delayAsString(skew, this, digits));
report_->reportBlankLine();
}
}
}
}
ClkDelayMap
ClkLatency::findClkDelays(ConstClockSeq &clks,
const Corner *corner,
bool include_internal_latency)
{
ClkDelayMap clk_delay_map;
// Make entries for the relevant clocks to filter path clocks.
for (const Clock *clk : clks)
clk_delay_map[clk];
for (Vertex *clk_vertex : *graph_->regClkVertices()) {
VertexPathIterator path_iter(clk_vertex, this);
while (path_iter.hasNext()) {
Path *path = path_iter.next();
const ClockEdge *path_clk_edge = path->clkEdge(this);
const PathAnalysisPt *path_ap = path->pathAnalysisPt(this);
if (path_clk_edge
&& (corner == nullptr
|| path_ap->corner() == corner)) {
const Clock *path_clk = path_clk_edge->clock();
auto delays_itr = clk_delay_map.find(path_clk);
if (delays_itr != clk_delay_map.end()) {
ClkDelays &clk_delays = delays_itr->second;
const RiseFall *clk_rf = path_clk_edge->transition();
const MinMax *min_max = path->minMax(this);
const RiseFall *end_rf = path->transition(this);
Delay latency = ClkDelays::latency(path, this);
Delay clk_latency;
bool exists;
clk_delays.latency(clk_rf, end_rf, min_max, clk_latency, exists);
if (!exists || delayGreater(latency, clk_latency, min_max, this))
clk_delays.setLatency(clk_rf, end_rf, min_max, path,
include_internal_latency, this);
}
}
}
}
return clk_delay_map;
}
////////////////////////////////////////////////////////////////
ClkDelays::ClkDelays()
{
for (auto src_rf_index : RiseFall::rangeIndex()) {
for (auto end_rf_index : RiseFall::rangeIndex()) {
for (auto mm_index : MinMax::rangeIndex()) {
insertion_[src_rf_index][end_rf_index][mm_index] = 0.0;
delay_[src_rf_index][end_rf_index][mm_index] = 0.0;
internal_latency_[src_rf_index][end_rf_index][mm_index] = 0.0;
latency_[src_rf_index][end_rf_index][mm_index] = 0.0;
exists_[src_rf_index][end_rf_index][mm_index] = false;
}
}
}
}
void
ClkDelays::delay(const RiseFall *src_rf,
const RiseFall *end_rf,
const MinMax *min_max,
// Return values.
Delay &insertion,
Delay &delay,
float &lib_clk_delay,
Delay &latency,
Path &path,
bool &exists) const
{
int src_rf_index = src_rf->index();
int end_rf_index = end_rf->index();
int mm_index = min_max->index();
path = path_[src_rf_index][end_rf_index][mm_index];
insertion = insertion_[src_rf_index][end_rf_index][mm_index];
delay = delay_[src_rf_index][end_rf_index][mm_index];
lib_clk_delay = internal_latency_[src_rf_index][end_rf_index][mm_index];
latency = latency_[src_rf_index][end_rf_index][mm_index];
exists = exists_[src_rf_index][end_rf_index][mm_index];
}
void
ClkDelays::latency(const RiseFall *src_rf,
const RiseFall *end_rf,
const MinMax *min_max,
// Return values.
Delay &latency,
bool &exists) const
{
int src_rf_index = src_rf->index();
int end_rf_index = end_rf->index();
int mm_index = min_max->index();
latency = latency_[src_rf_index][end_rf_index][mm_index];
exists = exists_[src_rf_index][end_rf_index][mm_index];
}
void
ClkDelays::setLatency(const RiseFall *src_rf,
const RiseFall *end_rf,
const MinMax *min_max,
Path *path,
bool include_internal_latency,
StaState *sta)
{
int src_rf_index = src_rf->index();
int end_rf_index = end_rf->index();
int mm_index = min_max->index();
float insertion = insertionDelay(path, sta);
insertion_[src_rf_index][end_rf_index][mm_index] = insertion;
float delay1 = delay(path, sta);
delay_[src_rf_index][end_rf_index][mm_index] = delay1;
float internal_latency = 0.0;
if (include_internal_latency) {
internal_latency = clkTreeDelay(path, sta);
internal_latency_[src_rf_index][end_rf_index][mm_index] = internal_latency;
}
float latency = insertion + delay1 + internal_latency;
latency_[src_rf_index][end_rf_index][mm_index] = latency;
path_[src_rf_index][end_rf_index][mm_index] = *path;
exists_[src_rf_index][end_rf_index][mm_index] = true;
}
Delay
ClkDelays::latency(Path *clk_path,
StaState *sta)
{
float insertion = insertionDelay(clk_path, sta);
float delay1 = delay(clk_path, sta);
float lib_clk_delay = clkTreeDelay(clk_path, sta);
return insertion + delay1 + lib_clk_delay;
}
float
ClkDelays::delay(Path *clk_path,
StaState *sta)
{
Arrival arrival = clk_path->arrival();
const ClockEdge *path_clk_edge = clk_path->clkEdge(sta);
return delayAsFloat(arrival) - path_clk_edge->time();
}
float
ClkDelays::insertionDelay(Path *clk_path,
StaState *sta)
{
const ClockEdge *clk_edge = clk_path->clkEdge(sta);
const Clock *clk = clk_edge->clock();
const RiseFall *clk_rf = clk_edge->transition();
const ClkInfo *clk_info = clk_path->clkInfo(sta);
const Pin *src_pin = clk_info->clkSrc();
const PathAnalysisPt *path_ap = clk_path->pathAnalysisPt(sta);
const MinMax *min_max = clk_path->minMax(sta);
return delayAsFloat(sta->search()->clockInsertion(clk, src_pin, clk_rf, min_max,
min_max, path_ap));
}
float
ClkDelays::clkTreeDelay(Path *clk_path,
StaState *sta)
{
const Vertex *vertex = clk_path->vertex(sta);
const Pin *pin = vertex->pin();
const LibertyPort *port = sta->network()->libertyPort(pin);
const MinMax *min_max = clk_path->minMax(sta);
const RiseFall *rf = clk_path->transition(sta);
float slew = delayAsFloat(clk_path->slew(sta));
return port->clkTreeDelay(slew, rf, min_max);
}
} // namespace