1 files changed, 37 insertions, 0 deletions
diff --git a/sysdeps/ieee754/float128/s_signbitf128.c b/sysdeps/ieee754/float128/s_signbitf128.c
new file mode 100644
index 0000000000..559df3b56c
--- /dev/null
+++ b/sysdeps/ieee754/float128/s_signbitf128.c
@@ -0,0 +1,37 @@
+/* Return nonzero value if number is negative.
+   Copyright (C) 2017-2018 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <float128_private.h>
+#include <math.h>
+#include <math_private.h>
+
+/* Once GCC >= 6.0 is required for building glibc, this implementation can
+   be removed and replaced with an inclusion of ldbl-128/s_signbitl.c.  */
+int
+__signbitf128 (_Float128 x)
+{
+#if __GNUC_PREREQ (6, 0)
+  return __builtin_signbit (x);
+#else
+  int64_t e;
+
+  GET_FLOAT128_MSW64 (e, x);
+  return e < 0;
+#endif
+}
+hidden_def (__signbitf128)