1 files changed, 83 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_fromfp_main.c b/sysdeps/ieee754/dbl-64/s_fromfp_main.c
new file mode 100644
index 0000000000..dfb70b434e
--- /dev/null
+++ b/sysdeps/ieee754/dbl-64/s_fromfp_main.c
@@ -0,0 +1,83 @@
+/* Round to integer type.  dbl-64 version.
+   Copyright (C) 2016-2018 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 <errno.h>
+#include <fenv.h>
+#include <math.h>
+#include <math_private.h>
+#include <libm-alias-double.h>
+#include <stdbool.h>
+#include <stdint.h>
+
+#define BIAS 0x3ff
+#define MANT_DIG 53
+
+#if UNSIGNED
+# define RET_TYPE uintmax_t
+#else
+# define RET_TYPE intmax_t
+#endif
+
+#include <fromfp.h>
+
+RET_TYPE
+FUNC (double x, int round, unsigned int width)
+{
+  if (width > INTMAX_WIDTH)
+    width = INTMAX_WIDTH;
+  uint64_t ix;
+  EXTRACT_WORDS64 (ix, x);
+  bool negative = (ix & 0x8000000000000000ULL) != 0;
+  if (width == 0)
+    return fromfp_domain_error (negative, width);
+  ix &= 0x7fffffffffffffffULL;
+  if (ix == 0)
+    return 0;
+  int exponent = ix >> (MANT_DIG - 1);
+  exponent -= BIAS;
+  int max_exponent = fromfp_max_exponent (negative, width);
+  if (exponent > max_exponent)
+    return fromfp_domain_error (negative, width);
+
+  ix &= ((1ULL << (MANT_DIG - 1)) - 1);
+  ix |= 1ULL << (MANT_DIG - 1);
+  uintmax_t uret;
+  bool half_bit, more_bits;
+  if (exponent >= MANT_DIG - 1)
+    {
+      uret = ix;
+      uret <<= exponent - (MANT_DIG - 1);
+      half_bit = false;
+      more_bits = false;
+    }
+  else if (exponent >= -1)
+    {
+      uint64_t h = 1ULL << (MANT_DIG - 2 - exponent);
+      half_bit = (ix & h) != 0;
+      more_bits = (ix & (h - 1)) != 0;
+      uret = ix >> (MANT_DIG - 1 - exponent);
+    }
+  else
+    {
+      uret = 0;
+      half_bit = false;
+      more_bits = true;
+    }
+  return fromfp_round_and_return (negative, uret, half_bit, more_bits, round,
+				  exponent, max_exponent, width);
+}