PathGroup revert f1b33edd9

Signed-off-by: James Cherry <cherry@parallaxsw.com>

include/sta/PathGroup.hh

@@ -29,7 +29,6 @@
 #include <map>
 #include <mutex>
 
-#include "BoundedHeap.hh"
 #include "SdcClass.hh"
 #include "StaState.hh"
 #include "SearchClass.hh"
@@ -70,7 +69,7 @@ public:
   ~PathGroup();
   const std::string &name() const { return name_; }
   const MinMax *minMax() const { return min_max_;}
-  PathEndSeq pathEnds() const;
+  PathEndSeq pathEnds() const { return path_ends_; }
   void insert(PathEnd *path_end);
   // Push group_path_count into path_ends.
   void pushEnds(PathEndSeq &path_ends);
@@ -93,6 +92,9 @@ protected:
             bool cmp_slack,
             const MinMax *min_max,
             const StaState *sta);
+  void ensureSortedMaxPaths();
+  void prune();
+  void sort();
 
   std::string name_;
   int group_path_count_;
@@ -101,9 +103,11 @@ protected:
   bool unique_edges_;
   float slack_min_;
   float slack_max_;
+  PathEndSeq path_ends_;
   const MinMax *min_max_;
   bool cmp_slack_;
-  BoundedHeap<PathEnd*, PathEndLess> heap_;
+  float threshold_;
+
   std::mutex lock_;
   const StaState *sta_;
 };

search/PathGroup.cc

@@ -100,41 +100,42 @@ PathGroup::PathGroup(const char *name,
   slack_max_(slack_max),
   min_max_(min_max),
   cmp_slack_(cmp_slack),
-  heap_(group_path_count, PathEndLess(cmp_slack, sta)),
+  threshold_(min_max->initValue()),
   sta_(sta)
 {
 }
 
 PathGroup::~PathGroup()
 {
-  PathEndSeq path_ends = heap_.extract();
-  deleteContents(path_ends);
-}
-
-PathEndSeq
-PathGroup::pathEnds() const
-{
-  return heap_.contents();
+  deleteContents(path_ends_);
 }
 
 bool
 PathGroup::saveable(PathEnd *path_end)
 {
+  float threshold;
+  {
+    LockGuard lock(lock_);
+    threshold = threshold_;
+  }
   if (cmp_slack_) {
     // Crpr increases the slack, so check the slack
     // without crpr first because it is expensive to find.
-    Slack slack = path_end->slackNoCrpr(sta_);
-    if (!delayIsInitValue(slack, min_max_)
-        && delayLessEqual(slack, slack_max_, sta_)) {
+    Slack slack_no_crpr = path_end->slackNoCrpr(sta_);
+    if (!delayIsInitValue(slack_no_crpr, min_max_)
+        && delayLessEqual(slack_no_crpr, threshold, sta_)
+        && delayLessEqual(slack_no_crpr, slack_max_, sta_)) {
       // Now check with crpr.
-      slack = path_end->slack(sta_);
-      return delayLessEqual(slack, slack_max_, sta_)
+      Slack slack = path_end->slack(sta_);
+      return delayLessEqual(slack, threshold, sta_)
+        && delayLessEqual(slack, slack_max_, sta_)
         && delayGreaterEqual(slack, slack_min_, sta_);
     }
   }
   else {
     const Arrival &arrival = path_end->dataArrivalTime(sta_);
-    return !delayIsInitValue(arrival, min_max_);
+    return !delayIsInitValue(arrival, min_max_)
+      && delayGreaterEqual(arrival, threshold, min_max_, sta_);
   }
   return false;
 }
@@ -176,33 +177,72 @@ void
 PathGroup::insert(PathEnd *path_end)
 {
   LockGuard lock(lock_);
-  auto [inserted, displaced] = heap_.insert(path_end);
-  if (inserted)
-    path_end->setPathGroup(this);
+  path_ends_.push_back(path_end);
+   path_end->setPathGroup(this);
+  if (group_path_count_ != group_path_count_max
+      && path_ends_.size() > static_cast<size_t>(group_path_count_) * 2)
+    prune();
+}
+
+void
+PathGroup::prune()
+{
+  sort();
+  VertexPathCountMap path_counts;
+  size_t end_count = 0;
+  for (unsigned i = 0; i < path_ends_.size(); i++) {
+    PathEnd *path_end = path_ends_[i];
+    Vertex *vertex = path_end->vertex(sta_);
+    // Squish up to endpoint_path_count path ends per vertex
+    // up to the front of path_ends_.
+    if (end_count < static_cast<size_t>(group_path_count_)
+        && path_counts[vertex] < static_cast<size_t>(endpoint_path_count_)) {
+      path_ends_[end_count++] = path_end;
+      path_counts[vertex]++;
+    }
+    else
+      delete path_end;
+  }
+  path_ends_.resize(end_count);
+
+  // Set a threshold to the bottom of the sorted list that future
+  // inserts need to beat.
+  PathEnd *last_end = path_ends_[end_count - 1];
+  if (cmp_slack_)
+    threshold_ = delayAsFloat(last_end->slack(sta_));
   else
-    delete path_end;
-  if (displaced)
-    delete *displaced;
+    threshold_ = delayAsFloat(last_end->dataArrivalTime(sta_));
 }
 
 void
 PathGroup::pushEnds(PathEndSeq &path_ends)
 {
-  if (!heap_.empty()) {
-    PathEndSeq ends = heap_.contents();
-    path_ends.reserve(path_ends.size() + ends.size());
-    // Append heap path ends to path_ends.
-    path_ends.insert(path_ends.end(),
-                     std::make_move_iterator(ends.begin()),
-                     std::make_move_iterator(ends.end()));
-  }
+  ensureSortedMaxPaths();
+  for (PathEnd *path_end : path_ends_)
+    path_ends.push_back(path_end);
+}
+
+void
+PathGroup::ensureSortedMaxPaths()
+{
+  if (path_ends_.size() > static_cast<size_t>(group_path_count_))
+    prune();
+  else
+    sort();
+}
+
+void
+PathGroup::sort()
+{
+  sta::sort(path_ends_, PathEndLess(cmp_slack_, sta_));
 }
 
 void
 PathGroup::clear()
 {
+  threshold_ = min_max_->initValue();
   LockGuard lock(lock_);
-  heap_.clear();
+  path_ends_.clear();
 }
 
 ////////////////////////////////////////////////////////////////
@@ -857,8 +897,11 @@ PathGroups::enumPathEnds(PathGroup *group,
   // enumerator.
   PathEnum path_enum(group_path_count, endpoint_path_count,
                      unique_pins, unique_edges, cmp_slack, this);
-  for (PathEnd *end : group->pathEnds())
-    path_enum.insert(end);
+  for (PathEnd *end : group->pathEnds()) {
+    if (group->saveable(end)
+        || group->enumMinSlackUnderMin(end))
+      path_enum.insert(end);
+  }
   group->clear();
 
   // Parallel path enumeratation to find the endpoint_path_count/max path ends.