From ba6ed5fa5f41918f94c297b67d3e29d886d37522 Mon Sep 17 00:00:00 2001
From: Benoit Jacob <jacob.benoit.1@gmail.com>
Date: Sat, 2 Jan 2010 13:04:04 -0500
Subject: [PATCH] Fix CoeffReadCost in Part: it must account for the cost of
 the conditional jump. This makes Part considered an "expensive" xpr  that
 must be evaluated in operations such as Product. This fixes bug #80.

---
 Eigen/src/Core/Part.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Eigen/src/Core/Part.h b/Eigen/src/Core/Part.h
index 96229f43b..65f4bc194 100644
--- a/Eigen/src/Core/Part.h
+++ b/Eigen/src/Core/Part.h
@@ -50,7 +50,7 @@ struct ei_traits<Part<MatrixType, Mode> > : ei_traits<MatrixType>
   typedef typename ei_unref<MatrixTypeNested>::type _MatrixTypeNested;
   enum {
     Flags = (_MatrixTypeNested::Flags & (HereditaryBits) & (~(PacketAccessBit | DirectAccessBit | LinearAccessBit))) | Mode,
-    CoeffReadCost = _MatrixTypeNested::CoeffReadCost
+    CoeffReadCost = _MatrixTypeNested::CoeffReadCost + ConditionalJumpCost
   };
 };