From 70bb5e9440861e2ef2f523300ac7b3836c6f07db Mon Sep 17 00:00:00 2001
From: James Cherry <cherry@parallaxsw.com>
Date: Wed, 15 Jan 2025 09:17:14 -0700
Subject: [PATCH] report_checks -endpoint_path_count -slack_min

Signed-off-by: James Cherry <cherry@parallaxsw.com>
---
 include/sta/PathEnd.hh   |  6 ++----
 include/sta/PathGroup.hh |  1 +
 search/PathEnd.cc        |  6 ++----
 search/PathEnum.cc       |  2 +-
 search/PathGroup.cc      | 38 ++++++++++++++++++++++++++++++++++++--
 5 files changed, 42 insertions(+), 11 deletions(-)

diff --git a/include/sta/PathEnd.hh b/include/sta/PathEnd.hh
index b004b36c..272f87e4 100644
--- a/include/sta/PathEnd.hh
+++ b/include/sta/PathEnd.hh
@@ -68,8 +68,7 @@ public:
   Path *path() { return &path_; }
   const Path *path() const { return &path_; }
   PathRef &pathRef() { return path_; }
-  virtual void setPath(PathEnumed *path,
-		       const StaState *sta);
+  virtual void setPath(const Path *path);
   Vertex *vertex(const StaState *sta) const;
   const MinMax *minMax(const StaState *sta) const;
   // Synonym for minMax().
@@ -256,8 +255,7 @@ public:
   virtual Slack slackNoCrpr(const StaState *sta) const;
   virtual int exceptPathCmp(const PathEnd *path_end,
 			    const StaState *sta) const;
-  virtual void setPath(PathEnumed *path,
-		       const StaState *sta);
+  virtual void setPath(const Path *path);
 
 protected:
   PathEndClkConstrained(Path *path,
diff --git a/include/sta/PathGroup.hh b/include/sta/PathGroup.hh
index 9e7b9e2c..586e5525 100644
--- a/include/sta/PathGroup.hh
+++ b/include/sta/PathGroup.hh
@@ -61,6 +61,7 @@ public:
   void pushEnds(PathEndSeq &path_ends);
   // Predicate to determine if a PathEnd is worth saving.
   bool saveable(PathEnd *path_end);
+  bool enumMinSlackUnderMin(PathEnd *path_end);
   int maxPaths() const { return group_path_count_; }
   PathGroupIterator *iterator();
   // This does NOT delete the path ends.
diff --git a/search/PathEnd.cc b/search/PathEnd.cc
index 02fb39a2..18c29828 100644
--- a/search/PathEnd.cc
+++ b/search/PathEnd.cc
@@ -51,8 +51,7 @@ PathEnd::~PathEnd()
 }
 
 void
-PathEnd::setPath(PathEnumed *path,
-		 const StaState *)
+PathEnd::setPath(const Path *path)
 {
   path_.init(path);
 }
@@ -523,8 +522,7 @@ PathEndClkConstrained::PathEndClkConstrained(Path *path,
 }
 
 void
-PathEndClkConstrained::setPath(PathEnumed *path,
-			       const StaState *)
+PathEndClkConstrained::setPath(const Path *path)
 {
   path_.init(path);
   crpr_valid_ = false;
diff --git a/search/PathEnum.cc b/search/PathEnum.cc
index 77621ffa..371b4a9b 100644
--- a/search/PathEnum.cc
+++ b/search/PathEnum.cc
@@ -377,7 +377,7 @@ PathEnumFaninVisitor::makeDivertedPathEnd(Path *after_div,
   path_enum_->makeDivertedPath(path_end_->path(), &before_div_, after_div,
 			       div_arc, div_path, after_div_copy);
   div_end = path_end_->copy();
-  div_end->setPath(div_path, this);
+  div_end->setPath(div_path);
 }
 
 void
diff --git a/search/PathGroup.cc b/search/PathGroup.cc
index 729d2a3c..6bd07a50 100644
--- a/search/PathGroup.cc
+++ b/search/PathGroup.cc
@@ -122,6 +122,38 @@ PathGroup::saveable(PathEnd *path_end)
   return false;
 }
 
+// endpoint_path_count > 1 with slack_min requires
+// saving endpoints with slack > slack_min so that
+// path enumeration can find them. Use the patg end
+// with the min(max) delay to prune ends that cannot
+// onion peel down to slack_min.
+bool
+PathGroup::enumMinSlackUnderMin(PathEnd *path_end)
+{
+  if (compare_slack_
+      && endpoint_path_count_ > 1
+      && slack_min_ > -INF) {
+    const Path *path = path_end->path();
+    PathAnalysisPt *other_ap = path->pathAnalysisPt(sta_)->tgtClkAnalysisPt();
+    const Tag *tag = path->tag(sta_);
+    VertexPathIterator other_iter(path->vertex(sta_),
+                                  path->transition(sta_),
+                                  other_ap, sta_);
+    while (other_iter.hasNext()) {
+      PathVertex *other = other_iter.next();
+      if (tagMatchCrpr(other->tag(sta_), tag)) {
+        PathEnd *end_min = path_end->copy();
+        end_min->setPath(other);
+        bool slack_under = fuzzyGreater(end_min->slackNoCrpr(sta_), slack_min_);
+        delete end_min;
+        if (slack_under)
+          return true;
+      }
+    }
+  }
+  return false;
+}
+
 void
 PathGroup::insert(PathEnd *path_end)
 {
@@ -700,7 +732,8 @@ MakePathEndsAll::vertexEnd(Vertex *)
                      path_end->path()->tag(sta_)->index());
 	  // Give the group a copy of the path end because
 	  // it may delete it during pruning.
-	  if (group->saveable(path_end)) {
+	  if (group->saveable(path_end)
+              || group->enumMinSlackUnderMin(path_end)) {
 	    group->insert(path_end->copy());
 	    unique_ends.insert(path_end);
 	    n++;
@@ -787,7 +820,8 @@ PathGroups::enumPathEnds(PathGroup *group,
   PathGroupIterator *end_iter = group->iterator();
   while (end_iter->hasNext()) {
     PathEnd *end = end_iter->next();
-    if (group->saveable(end))
+    if (group->saveable(end)
+        || group->enumMinSlackUnderMin(end))
       path_enum.insert(end);
   }
   delete end_iter;