[PATCH] [BZ #17031][PowerPC64] Fix nearbyintl failure for few inputs

[Rajalakshmi Srinivasaraghavan]

This patch fixes few failures in nearbyintl() where the fraction part
is close to 0.5.

	[BZ #17031]
	sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c: Consider the low
	double, adjusted for any remainder from the high double.

Signed-off-by: Rajalakshmi Srinivasaraghavan <raji@linux.vnet.ibm.com>
---
 NEWS                                       | 2 +-
 sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c | 5 +++++
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/NEWS b/NEWS
index 622cdbf..eb6b736 100644
--- a/NEWS
+++ b/NEWS
@@ -19,7 +19,7 @@ Version 2.20
   16791, 16796, 16799, 16800, 16815, 16823, 16824, 16831, 16838, 16849,
   16854, 16876, 16877, 16878, 16882, 16885, 16888, 16890, 16912, 16915,
   16916, 16917, 16922, 16927, 16928, 16932, 16943, 16958, 16965, 16966,
-  16967, 16977, 16978, 16984, 16990, 17009.
+  16967, 16977, 16978, 16984, 16990, 17009, 17031.
 
 * The minimum Linux kernel version that this version of the GNU C Library
   can be used with is 2.6.32.
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c b/sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c
index 4e997a6..8f34604 100644
--- a/sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c
+++ b/sysdeps/ieee754/ldbl-128ibm/s_nearbyintl.c
@@ -38,6 +38,7 @@ __nearbyintl (long double x)
 
   if (fabs (u.d[0].d) < TWO52)
     {
+      double xh = u.d[0].d;
       double high = u.d[0].d;
       feholdexcept (&env);
       if (high > 0.0)
@@ -52,6 +53,10 @@ __nearbyintl (long double x)
 	  high += TWO52;
           if (high == 0.0) high = -0.0;
 	}
+      if (u.d[1].d > 0.0 && (xh - high == 0.5))
+        high += 1.0;
+      else if (u.d[1].d < 0.0 && (-(xh - high) == 0.5))
+        high -= 1.0;
       u.d[0].d = high;
       u.d[1].d = 0.0;
       math_force_eval (u.d[0]);
-- 
1.8.4.2