From d5fa5001a7c6ba3ea29c5a4f18aebb8c1ec71dd6 Mon Sep 17 00:00:00 2001
From: Jeff Dean <anonymous@invalid.net>
Date: Thu, 13 Jun 2013 18:17:27 +0200
Subject: [PATCH] Fix bug #613: psqrt was incorrect for small numbers

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

diff --git a/Eigen/src/Core/arch/SSE/MathFunctions.h b/Eigen/src/Core/arch/SSE/MathFunctions.h
index 5ede55fba..1d1a98a9d 100644
--- a/Eigen/src/Core/arch/SSE/MathFunctions.h
+++ b/Eigen/src/Core/arch/SSE/MathFunctions.h
@@ -450,7 +450,7 @@ Packet4f psqrt<Packet4f>(const Packet4f& _x)
   Packet4f half = pmul(_x, pset1<Packet4f>(.5f));
 
   /* select only the inverse sqrt of non-zero inputs */
-  Packet4f non_zero_mask = _mm_cmpgt_ps(_x, pset1<Packet4f>(std::numeric_limits<float>::epsilon()));
+  Packet4f non_zero_mask = _mm_cmpgt_ps(_x, pset1<Packet4f>((std::numeric_limits<float>::min)()));
   Packet4f x = _mm_and_ps(non_zero_mask, _mm_rsqrt_ps(_x));
 
   x = pmul(x, psub(pset1<Packet4f>(1.5f), pmul(half, pmul(x,x))));