Add PropertyRegistry for Clock. (The-OpenROAD-Project#298)

* Add PropertyRegistry for Clock.

Signed-off-by: Mike Inouye <mikeinouye@google.com>

* Remove extra blank line.

---------

Signed-off-by: Mike Inouye <mikeinouye@google.com>

Author: mikesinouye

include/sta/Property.hh

@@ -94,10 +94,10 @@ public:
                             const std::string property);
 
   // Define handler for external property.
-  // proerties->defineProperty("foo",
-  //                           [] (const Instance *, Sta *) -> PropertyValue {
-  //                             return PropertyValue("bar");
-  //                           });
+  // properties->defineProperty("foo",
+  //                            [] (const Instance *, Sta *) -> PropertyValue {
+  //                              return PropertyValue("bar");
+  //                            });
   void defineProperty(std::string &property,
                       PropertyRegistry<const Library *>::PropertyHandler handler);
   void defineProperty(std::string &property,
@@ -116,6 +116,8 @@ public:
                       PropertyRegistry<const Pin *>::PropertyHandler handler);
   void defineProperty(std::string &property,
                       PropertyRegistry<const Net *>::PropertyHandler handler);
+  void defineProperty(std::string &property,
+                      PropertyRegistry<const Clock *>::PropertyHandler handler);
 
 protected:
   PropertyValue portSlew(const Port *port,
@@ -159,6 +161,7 @@ protected:
   PropertyRegistry<const Instance*> registry_instance_;
   PropertyRegistry<const Pin*> registry_pin_;
   PropertyRegistry<const Net*> registry_net_;
+  PropertyRegistry<const Clock*> registry_clock_;
 
   Sta *sta_;
 };

search/Property.cc

@@ -1240,8 +1240,14 @@ Properties::getProperty(const Clock *clk,
     return PropertyValue(clk->isVirtual());
   else if (property == "is_propagated")
     return PropertyValue(clk->isPropagated());
-  else
-    throw PropertyUnknown("clock", property);
+  else {
+    PropertyValue value = registry_clock_.getProperty(clk, property,
+                                                      "clock", sta_);
+    if (value.type() != PropertyValue::Type::type_none)
+      return value;
+    else
+      throw PropertyUnknown("clock", property);
+  }
 }
 
 ////////////////////////////////////////////////////////////////
@@ -1376,6 +1382,13 @@ Properties::defineProperty(std::string &property,
   registry_net_.defineProperty(property, handler);
 }
 
+void
+Properties::defineProperty(std::string &property,
+                           PropertyRegistry<const Clock *>::PropertyHandler handler)
+{
+  registry_clock_.defineProperty(property, handler);
+}
+
 ////////////////////////////////////////////////////////////////
 
 template<class TYPE>