From ac5377e16186c35ae1609245838825c07d0aa79f Mon Sep 17 00:00:00 2001
From: Gael Guennebaud <g.gael@free.fr>
Date: Wed, 21 Sep 2016 17:26:04 +0200
Subject: [PATCH] Improve cost estimation of complex division

---
 Eigen/src/Core/util/XprHelper.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Eigen/src/Core/util/XprHelper.h b/Eigen/src/Core/util/XprHelper.h
index fa60008ef..088a65240 100644
--- a/Eigen/src/Core/util/XprHelper.h
+++ b/Eigen/src/Core/util/XprHelper.h
@@ -671,6 +671,14 @@ struct scalar_div_cost {
   enum { value = 8*NumTraits<T>::MulCost };
 };
 
+template<typename T,bool Vectorized>
+struct scalar_div_cost<std::complex<T>, Vectorized> {
+  enum { value = 2*scalar_div_cost<T>::value
+               + 6*NumTraits<T>::MulCost
+               + 3*NumTraits<T>::AddCost
+  };
+};
+
 
 template<bool Vectorized>
 struct scalar_div_cost<signed long,Vectorized,typename conditional<sizeof(long)==8,void,false_type>::type> { enum { value = 24 }; };