crpr for clk paths

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

include/sta/Search.hh

@@ -238,25 +238,26 @@ public:
 		     const RiseFall *to_rf,
 		     const MinMax *min_max,
 		     const PathAnalysisPt *path_ap);
-  virtual Tag *thruTag(Tag *from_tag,
-		       Edge *edge,
-		       const RiseFall *to_rf,
-		       const MinMax *min_max,
- 		       const PathAnalysisPt *path_ap);
-  virtual Tag *thruClkTag(PathVertex *from_path,
-			  Tag *from_tag,
-			  bool to_propagates_clk,
-			  Edge *edge,
-			  const RiseFall *to_rf,
-			  const MinMax *min_max,
-			  const PathAnalysisPt *path_ap);
+  Tag *thruTag(Tag *from_tag,
+               Edge *edge,
+               const RiseFall *to_rf,
+               const MinMax *min_max,
+               const PathAnalysisPt *path_ap);
+  Tag *thruClkTag(PathVertex *from_path,
+                  Tag *from_tag,
+                  bool to_propagates_clk,
+                  Edge *edge,
+                  const RiseFall *to_rf,
+                  const MinMax *min_max,
+                  const PathAnalysisPt *path_ap);
   ClkInfo *thruClkInfo(PathVertex *from_path,
-		       ClkInfo *from_tag_clk,
-		       Edge *edge,
-		       Vertex *to_vertex,
-		       const Pin *to_pin,
-		       const MinMax *min_max,
- 		       const PathAnalysisPt *path_ap);
+                       ClkInfo *from_clk_info,
+                       bool from_is_clk,
+                       Edge *edge,
+                       const Pin *to_pin,
+                       bool to_is_clk,
+                       const MinMax *min_max,
+                       const PathAnalysisPt *path_ap);
   ClkInfo *clkInfoWithCrprClkPath(ClkInfo *from_clk_info,
 				  PathVertex *from_path,
 				  const PathAnalysisPt *path_ap);

search/ClkInfo.hh

@@ -54,8 +54,8 @@ public:
   const Arrival &insertion() const { return insertion_; }
   ClockUncertainties *uncertainties() const { return uncertainties_; }
   PathAPIndex pathAPIndex() const { return path_ap_index_; }
-  // Clock path for the last driver in the clock network used for
-  // crpr resolution.
+  // Clock path used for crpr resolution.
+  // Null for clocks because the path cannot point to itself.
   PathVertexRep &crprClkPath() { return crpr_clk_path_; }
   const PathVertexRep &crprClkPath() const { return crpr_clk_path_; }
   VertexId crprClkVertexId() const;

search/Crpr.cc

@@ -152,13 +152,22 @@ CheckCrpr::checkCrpr1(const Path *src_path,
 {
   crpr = 0.0;
   crpr_pin = nullptr;
-  ClkInfo *src_clk_info = src_path->tag(this)->clkInfo();
+  const Tag *src_tag = src_path->tag(this);
+  ClkInfo *src_clk_info = src_tag->clkInfo();
   ClkInfo *tgt_clk_info = tgt_clk_path->tag(this)->clkInfo();
   const Clock *src_clk = src_clk_info->clock();
   const Clock *tgt_clk = tgt_clk_info->clock();
-  const PathVertex src_clk_path1(src_clk_info->crprClkPath(), this);
-  const PathVertex *src_clk_path =
-    src_clk_path1.isNull() ? nullptr : &src_clk_path1;
+  PathVertex src_clk_path1;
+  PathVertexRep &src_crpr_clk_path = src_clk_info->crprClkPath();
+  const PathVertex *src_clk_path = nullptr;
+  if (src_tag->isClock()) {
+    src_clk_path1.init(src_path->vertex(this), src_path->tag(this), this);
+    src_clk_path = &src_clk_path1;
+  }
+  else if (!src_crpr_clk_path.isNull()) {
+    src_clk_path1.init(src_crpr_clk_path, this);
+    src_clk_path = &src_clk_path1;
+  }
   const MinMax *src_clk_min_max =
     src_clk_path ? src_clk_path->minMax(this) : src_path->minMax(this);
   if (src_clk && tgt_clk

search/Search.cc

@@ -2417,8 +2417,9 @@ Search::thruClkTag(PathVertex *from_path,
 		    && to_propagates_clk
 		    && (role->isWire()
 			|| role == TimingRole::combinational()));
-  ClkInfo *to_clk_info = thruClkInfo(from_path, from_clk_info,
-				     edge, to_vertex, to_pin, min_max, path_ap);
+  ClkInfo *to_clk_info = thruClkInfo(from_path, from_clk_info, from_is_clk,
+				     edge, to_pin, to_is_clk,
+                                     min_max, path_ap);
   Tag *to_tag = mutateTag(from_tag,from_pin,from_rf,from_is_clk,from_clk_info,
 			  to_pin, to_rf, to_is_clk, to_is_reg_clk, false,
 			  to_clk_info, nullptr, min_max, path_ap);
@@ -2429,9 +2430,10 @@ Search::thruClkTag(PathVertex *from_path,
 ClkInfo *
 Search::thruClkInfo(PathVertex *from_path,
 		    ClkInfo *from_clk_info,
+                    bool from_is_clk,
 		    Edge *edge,
-		    Vertex *to_vertex,
 		    const Pin *to_pin,
+                    bool to_is_clk,
 		    const MinMax *min_max,
 		    const PathAnalysisPt *path_ap)
 {
@@ -2462,7 +2464,7 @@ Search::thruClkInfo(PathVertex *from_path,
 
   PathVertex *to_crpr_clk_path = nullptr;
   if (sdc_->crprActive()
-      && to_vertex->isRegClk()) {
+      && from_is_clk && !to_is_clk) {
     to_crpr_clk_path = from_path;
     changed = true;
   }