1 files changed, 52 insertions, 0 deletions
diff --git a/sysdeps/riscv/rv64/rvd/s_nearbyint.c b/sysdeps/riscv/rv64/rvd/s_nearbyint.c
new file mode 100644
index 0000000000..e17f038429
--- /dev/null
+++ b/sysdeps/riscv/rv64/rvd/s_nearbyint.c
@@ -0,0 +1,52 @@
+/* nearbyint().  RISC-V version.
+   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 <math.h>
+#include <math_private.h>
+#include <libm-alias-double.h>
+#include <stdint.h>
+
+double
+__nearbyint (double x)
+{
+  int flags = riscv_getflags ();
+  bool nan = isnan (x);
+  double mag = fabs (x);
+
+  if (nan)
+    return x + x;
+
+  if (mag < (1ULL << __DBL_MANT_DIG__))
+    {
+      int64_t i;
+      double new_x;
+
+      asm volatile ("fcvt.l.d %0, %1" : "=r" (i) : "f" (x));
+      asm volatile ("fcvt.d.l %0, %1" : "=f" (new_x) : "r" (i));
+
+      /* nearbyint(-0) == -0, and in general we'll always have the same
+	 sign as our input.  */
+      x = copysign (new_x, x);
+
+      riscv_setflags (flags);
+    }
+
+  return x;
+}
+
+libm_alias_double (__nearbyint, nearbyint)