From 6c2e26cbbd3c9d64a93b3c5284135be4508aec81 Mon Sep 17 00:00:00 2001
From: Adriano dos Santos Fernandes <adrianosf@gmail.com>
Date: Mon, 17 Oct 2016 13:03:24 -0200
Subject: [PATCH] Fixed CORE-5314 - UDFs declared with large varchars take
 excessive time to execute.

---
 src/dsql/ExprNodes.cpp | 13 ++++++++++---
 src/dsql/ExprNodes.h   |  7 +++++++
 src/jrd/fun.epp        |  3 +--
 src/jrd/fun_proto.h    |  2 +-
 4 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/src/dsql/ExprNodes.cpp b/src/dsql/ExprNodes.cpp
index c023688097..83efb03a41 100644
--- a/src/dsql/ExprNodes.cpp
+++ b/src/dsql/ExprNodes.cpp
@@ -11260,7 +11260,7 @@ ValueExprNode* UdfCallNode::pass2(thread_db* tdbb, CompilerScratch* csb)
 	dsc desc;
 	getDesc(tdbb, csb, &desc);
 
-	impureOffset = CMP_impure(csb, sizeof(impure_value));
+	impureOffset = CMP_impure(csb, sizeof(Impure));
 
 	if (function->isDefined() && !function->fun_entrypoint)
 	{
@@ -11282,7 +11282,8 @@ ValueExprNode* UdfCallNode::pass2(thread_db* tdbb, CompilerScratch* csb)
 dsc* UdfCallNode::execute(thread_db* tdbb, jrd_req* request) const
 {
 	UCHAR* impure = request->getImpure<UCHAR>(impureOffset);
-	impure_value* value = request->getImpure<impure_value>(impureOffset);
+	Impure* impureArea = request->getImpure<Impure>(impureOffset);
+	impure_value* value = &impureArea->value;
 
 	USHORT& invariantFlags = value->vlu_flags;
 
@@ -11347,7 +11348,13 @@ dsc* UdfCallNode::execute(thread_db* tdbb, jrd_req* request) const
 		else
 			value->vlu_desc.dsc_address = (UCHAR*) &value->vlu_misc;
 
-		FUN_evaluate(tdbb, function, args->items, value);
+		if (!impureArea->temp)
+		{
+			impureArea->temp =
+				FB_NEW_POOL(*tdbb->getDefaultPool()) Array<UCHAR>(*tdbb->getDefaultPool());
+		}
+
+		FUN_evaluate(tdbb, function, args->items, value, *impureArea->temp);
 	}
 	else
 	{
diff --git a/src/dsql/ExprNodes.h b/src/dsql/ExprNodes.h
index 2b8b222c07..a557aa54da 100644
--- a/src/dsql/ExprNodes.h
+++ b/src/dsql/ExprNodes.h
@@ -1681,6 +1681,13 @@ public:
 
 class UdfCallNode : public TypedNode<ValueExprNode, ExprNode::TYPE_UDF_CALL>
 {
+private:
+	struct Impure
+	{
+		impure_value value;	// must be first
+		Firebird::Array<UCHAR>* temp;
+	};
+
 public:
 	explicit UdfCallNode(MemoryPool& pool, const Firebird::QualifiedName& aName,
 		ValueListNode* aArgs = NULL);
diff --git a/src/jrd/fun.epp b/src/jrd/fun.epp
index d9ded9b2bb..2efedbacb1 100644
--- a/src/jrd/fun.epp
+++ b/src/jrd/fun.epp
@@ -303,7 +303,7 @@ static bool private_move(Jrd::thread_db* tdbb, dsc* from, dsc* to);
 
 
 void FUN_evaluate(thread_db* tdbb, const Function* function, const NestValueArray& node,
-	impure_value* value)
+	impure_value* value, Array<UCHAR>& temp)
 {
 /**************************************
  *
@@ -370,7 +370,6 @@ void FUN_evaluate(thread_db* tdbb, const Function* function, const NestValueArra
 	try {
 
 	UDF_ARG args[MAX_UDF_ARGUMENTS + 1];
-	HalfStaticArray<UCHAR, 800> temp;
 
 	// Start by constructing argument list
 	UCHAR* temp_ptr = temp.getBuffer(function->fun_temp_length + FB_DOUBLE_ALIGN);
diff --git a/src/jrd/fun_proto.h b/src/jrd/fun_proto.h
index 29411694c1..b32cc0503c 100644
--- a/src/jrd/fun_proto.h
+++ b/src/jrd/fun_proto.h
@@ -37,7 +37,7 @@ public:
 };
 
 void FUN_evaluate(Jrd::thread_db*, const Jrd::Function*, const Jrd::NestValueArray&,
-	Jrd::impure_value*);
+	Jrd::impure_value*, Firebird::Array<UCHAR>& temp);
 
 
 #endif // JRD_FUN_PROTO_H