Fix memory leaks of ``Array`` objects detected by ASan.

Some of these leaks were introduced by the factory constructor for Array
objects (f049ff3bc04daead8c3bb9f06e89e71e2054c82a) but a few others have
been around for far longer.

This leak was fixed by introducing a ``ArrayCache`` object which has two
purposes

* Retains ownership of all created ``Array`` objects and destroys them when
  the ``ArrayCache`` destructor is called.
* Mimic the caching behaviour for symbolic arrays that was introduced
  by f049ff3bc04daead8c3bb9f06e89e71e2054c82a where arrays with the same
  name and size get "uniqued".

The Executor now maintains a ``arrayCache`` member that it uses and
passes by pointer to objects that need to construct ``Array`` objects (i.e.
``ObjectState``). This way when the Executor is destroyed all the
``Array`` objects get freed which seems like the right time to do this.

For Kleaver the ``ParserImpl`` has a ``TheArrayCache`` member that is
used for building ``Array`` objects. This means that the Parser must
live as long as the built expressions will be used otherwise we will
have a use after free. I'm not sure this is the right design choice.
It might be better to transfer ownership of the ``Array`` objects to
the root ``Decl`` returned by the parser.

1 files changed, 0 insertions, 35 deletions

diff --git a/lib/Expr/Expr.cpp b/lib/Expr/Expr.cpp
index baa85663..2c64aff4 100644
--- a/lib/Expr/Expr.cpp
+++ b/lib/Expr/Expr.cpp
@@ -494,41 +494,6 @@ unsigned Array::computeHash() {
   hashValue = res;
   return hashValue; 
 }
-
-std::map<unsigned, std::vector<const Array *> *> Array::symbolicArraySingletonMap;
-
-const Array * Array::CreateArray(const std::string &_name, uint64_t _size,
-                                 const ref<ConstantExpr> *constantValuesBegin,
-                                 const ref<ConstantExpr> *constantValuesEnd,
-                                 Expr::Width _domain,
-				 Expr::Width _range) {
-
-  const Array * array = new Array(_name, _size, constantValuesBegin, constantValuesEnd, _domain,_range);
-  if (array->constantValues.size() == 0) { // symbolic array
-    unsigned hash = array->hash();
-    std::vector<const Array *> * bucket = Array::symbolicArraySingletonMap[hash];
-    if (bucket){
-      for (std::vector<const Array*>::const_iterator it = bucket->begin();
-	   it != bucket->end(); it ++){
-        const Array* prospect = *it;
-	if (prospect->size == array->size && prospect->name == array->name){
-    	  delete array;
-    	  return prospect;
-    	}
-      }
-      bucket->push_back(array);
-      return array;
-    } else {
-      bucket = new std::vector<const Array *>();
-      bucket->push_back(array);
-      Array::symbolicArraySingletonMap[hash] = bucket;
-      return array;
-    }
-  } else { // concrete array
-    return array;
-  }
-}
-
 /***/
 
 ref<Expr> ReadExpr::create(const UpdateList &ul, ref<Expr> index) {