readLibraryAttributes only call when non-empty library

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

liberty/LibertyParser.cc

@@ -324,6 +324,24 @@ LibertyGroup::clear()
   deleteContents(variables_);
 }
 
+bool
+LibertyGroup::empty() const
+{
+  return subgroups_.empty()
+    && simple_attr_map_.empty()
+    && complex_attr_map_.empty()
+    && define_map_.empty();
+}
+
+bool
+LibertyGroup::oneGroupOnly() const
+{
+  return subgroups_.size() == 1
+    && simple_attr_map_.empty()
+    && complex_attr_map_.empty()
+    && define_map_.empty();
+}
+
 void
 LibertyGroup::addSubgroup(LibertyGroup *subgroup)
 {

liberty/LibertyParser.hh

@@ -127,6 +127,8 @@ public:
                int line);
   ~LibertyGroup();
   void clear();
+  bool empty() const;
+  bool oneGroupOnly() const;
   const std::string &type() const { return type_; }
   const LibertyAttrValueSeq &params() const { return params_; }
   // First param as a string.

liberty/LibertyReader.cc

@@ -151,7 +151,8 @@ LibertyReader::endLibrary(const LibertyGroup *library_group,
                           LibertyGroup *)
 {
   // If a library has no cells endCell is not called.
-  readLibraryAttributes(library_group);
+  if (!library_group->empty())
+    readLibraryAttributes(library_group);
   checkThresholds(library_group);
   delete library_group;
 }
@@ -166,7 +167,8 @@ LibertyReader::endCell(const LibertyGroup *cell_group,
   // Normally they are all defined by the first cell, but there
   // are libraries that define table templates and bus tyupes
   // between cells.
-  readLibraryAttributes(library_group);
+  if (!library_group->oneGroupOnly())
+    readLibraryAttributes(library_group);
 
   const char *name = cell_group->firstName();
   if (name) {