1 files changed, 38 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_f64xsubf128.c b/sysdeps/ieee754/ldbl-128/s_f64xsubf128.c
new file mode 100644
index 0000000000..c9a63d9e84
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/s_f64xsubf128.c
@@ -0,0 +1,38 @@
+/* Subtract _Float128 values, converting the result to _Float64x.
+   Copyright (C) 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 <math.h>
+#include <math-narrow.h>
+
+/* math_ldbl.h defines _Float128 to long double for this directory,
+   but when they are different, this function must be defined with
+   _Float128 arguments to avoid defining an alias with an incompatible
+   type.  */
+#undef _Float128
+
+_Float64x
+__f64xsubf128 (_Float128 x, _Float128 y)
+{
+#if __HAVE_FLOAT64X_LONG_DOUBLE && __HAVE_DISTINCT_FLOAT128
+  NARROW_SUB_ROUND_TO_ODD (x, y, _Float64x, union ieee854_long_double, l,
+			   mantissa3);
+#else
+  NARROW_SUB_TRIVIAL (x, y, _Float64x);
+#endif
+}
+libm_alias_float64x_float128 (sub)