improve performance of countif

Author: taiyang-li

src/Analyzer/Passes/RewriteAggregateFunctionWithIfPass.cpp

@@ -72,15 +72,9 @@ class RewriteAggregateFunctionWithIfVisitor : public InDepthQueryTreeVisitorWith
 
                 QueryTreeNodes new_arguments{2};
 
-                /// We need to preserve the output type from if()
-                if (if_arguments_nodes[1]->getResultType()->getName() != if_node->getResultType()->getName())
-                {
-                    /// For count, adding an extra cast is too heavy for the benefit.
-                    if (lower_name == "count")
-                        return;
-
+                /// We need to preserve the output type from if(). Notice that the return type of count() is the same either way
+                if (if_arguments_nodes[1]->getResultType()->getName() != if_node->getResultType()->getName() && lower_name != "count")
                     new_arguments[0] = createCastFunction(std::move(if_arguments_nodes[1]), if_node->getResultType(), getContext());
-                }
                 else
                     new_arguments[0] = std::move(if_arguments_nodes[1]);
 
@@ -105,14 +99,9 @@ class RewriteAggregateFunctionWithIfVisitor : public InDepthQueryTreeVisitorWith
 
                 QueryTreeNodes new_arguments{2};
 
-                if (if_arguments_nodes[2]->getResultType()->getName() != if_node->getResultType()->getName())
-                {
-                    /// For count, adding an extra cast is too heavy for the benefit.
-                    if (lower_name == "count")
-                        return;
-
+                /// We need to preserve the output type from if(). Notice that the return type of count() is the same either way
+                if (if_arguments_nodes[2]->getResultType()->getName() != if_node->getResultType()->getName() && lower_name != "count")
                     new_arguments[0] = createCastFunction(std::move(if_arguments_nodes[2]), if_node->getResultType(), getContext());
-                }
                 else
                     new_arguments[0] = std::move(if_arguments_nodes[2]);