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-rw-r--r--sysdeps/ieee754/dbl-64/s_roundeven.c106
-rw-r--r--sysdeps/ieee754/dbl-64/wordsize-64/s_roundeven.c72
-rw-r--r--sysdeps/ieee754/flt-32/s_roundevenf.c68
-rw-r--r--sysdeps/ieee754/ldbl-128/s_roundevenl.c102
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_roundevenl.c69
-rw-r--r--sysdeps/ieee754/ldbl-96/s_roundevenl.c124
-rw-r--r--sysdeps/ieee754/ldbl-opt/Makefile4
-rw-r--r--sysdeps/ieee754/ldbl-opt/nldbl-roundeven.c26
8 files changed, 570 insertions, 1 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_roundeven.c b/sysdeps/ieee754/dbl-64/s_roundeven.c
new file mode 100644
index 0000000000..27e15e35ad
--- /dev/null
+++ b/sysdeps/ieee754/dbl-64/s_roundeven.c
@@ -0,0 +1,106 @@
+/* Round to nearest integer value, rounding halfway cases to even.
+   dbl-64 version.
+   Copyright (C) 2016 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 <stdint.h>
+
+#define BIAS 0x3ff
+#define MANT_DIG 53
+#define MAX_EXP (2 * BIAS + 1)
+
+double
+roundeven (double x)
+{
+  uint32_t hx, lx, uhx;
+  EXTRACT_WORDS (hx, lx, x);
+  uhx = hx & 0x7fffffff;
+  int exponent = uhx >> (MANT_DIG - 1 - 32);
+  if (exponent >= BIAS + MANT_DIG - 1)
+    {
+      /* Integer, infinity or NaN.  */
+      if (exponent == MAX_EXP)
+	/* Infinity or NaN; quiet signaling NaNs.  */
+	return x + x;
+      else
+	return x;
+    }
+  else if (exponent >= BIAS + MANT_DIG - 32)
+    {
+      /* Not necessarily an integer; integer bit is in low word.
+	 Locate the bits with exponents 0 and -1.  */
+      int int_pos = (BIAS + MANT_DIG - 1) - exponent;
+      int half_pos = int_pos - 1;
+      uint32_t half_bit = 1U << half_pos;
+      uint32_t int_bit = 1U << int_pos;
+      if ((lx & (int_bit | (half_bit - 1))) != 0)
+	{
+	  /* Carry into the exponent works correctly.  No need to test
+	     whether HALF_BIT is set.  */
+	  lx += half_bit;
+	  hx += lx < half_bit;
+	}
+      lx &= ~(int_bit - 1);
+    }
+  else if (exponent == BIAS + MANT_DIG - 33)
+    {
+      /* Not necessarily an integer; integer bit is bottom of high
+	 word, half bit is top of low word.  */
+      if (((hx & 1) | (lx & 0x7fffffff)) != 0)
+	{
+	  lx += 0x80000000;
+	  hx += lx < 0x80000000;
+	}
+      lx = 0;
+    }
+  else if (exponent >= BIAS)
+    {
+      /* At least 1; not necessarily an integer, integer bit and half
+	 bit are in the high word.  Locate the bits with exponents 0
+	 and -1 (when the unbiased exponent is 0, the bit with
+	 exponent 0 is implicit, but as the bias is odd it is OK to
+	 take it from the low bit of the exponent).  */
+      int int_pos = (BIAS + MANT_DIG - 33) - exponent;
+      int half_pos = int_pos - 1;
+      uint32_t half_bit = 1U << half_pos;
+      uint32_t int_bit = 1U << int_pos;
+      if (((hx & (int_bit | (half_bit - 1))) | lx) != 0)
+	hx += half_bit;
+      hx &= ~(int_bit - 1);
+      lx = 0;
+    }
+  else if (exponent == BIAS - 1 && (uhx > 0x3fe00000 || lx != 0))
+    {
+      /* Interval (0.5, 1).  */
+      hx = (hx & 0x80000000) | 0x3ff00000;
+      lx = 0;
+    }
+  else
+    {
+      /* Rounds to 0.  */
+      hx &= 0x80000000;
+      lx = 0;
+    }
+  INSERT_WORDS (x, hx, lx);
+  return x;
+}
+hidden_def (roundeven)
+#ifdef NO_LONG_DOUBLE
+weak_alias (roundeven, roundevenl)
+#endif
diff --git a/sysdeps/ieee754/dbl-64/wordsize-64/s_roundeven.c b/sysdeps/ieee754/dbl-64/wordsize-64/s_roundeven.c
new file mode 100644
index 0000000000..1fa3ef319d
--- /dev/null
+++ b/sysdeps/ieee754/dbl-64/wordsize-64/s_roundeven.c
@@ -0,0 +1,72 @@
+/* Round to nearest integer value, rounding halfway cases to even.
+   dbl-64/wordsize-64 version.
+   Copyright (C) 2016 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 <stdint.h>
+
+#define BIAS 0x3ff
+#define MANT_DIG 53
+#define MAX_EXP (2 * BIAS + 1)
+
+double
+roundeven (double x)
+{
+  uint64_t ix, ux;
+  EXTRACT_WORDS64 (ix, x);
+  ux = ix & 0x7fffffffffffffffULL;
+  int exponent = ux >> (MANT_DIG - 1);
+  if (exponent >= BIAS + MANT_DIG - 1)
+    {
+      /* Integer, infinity or NaN.  */
+      if (exponent == MAX_EXP)
+	/* Infinity or NaN; quiet signaling NaNs.  */
+	return x + x;
+      else
+	return x;
+    }
+  else if (exponent >= BIAS)
+    {
+      /* At least 1; not necessarily an integer.  Locate the bits with
+	 exponents 0 and -1 (when the unbiased exponent is 0, the bit
+	 with exponent 0 is implicit, but as the bias is odd it is OK
+	 to take it from the low bit of the exponent).  */
+      int int_pos = (BIAS + MANT_DIG - 1) - exponent;
+      int half_pos = int_pos - 1;
+      uint64_t half_bit = 1ULL << half_pos;
+      uint64_t int_bit = 1ULL << int_pos;
+      if ((ix & (int_bit | (half_bit - 1))) != 0)
+	/* Carry into the exponent works correctly.  No need to test
+	   whether HALF_BIT is set.  */
+	ix += half_bit;
+      ix &= ~(int_bit - 1);
+    }
+  else if (exponent == BIAS - 1 && ux > 0x3fe0000000000000ULL)
+    /* Interval (0.5, 1).  */
+    ix = (ix & 0x8000000000000000ULL) | 0x3ff0000000000000ULL;
+  else
+    /* Rounds to 0.  */
+    ix &= 0x8000000000000000ULL;
+  INSERT_WORDS64 (x, ix);
+  return x;
+}
+hidden_def (roundeven)
+#ifdef NO_LONG_DOUBLE
+weak_alias (roundeven, roundevenl)
+#endif
diff --git a/sysdeps/ieee754/flt-32/s_roundevenf.c b/sysdeps/ieee754/flt-32/s_roundevenf.c
new file mode 100644
index 0000000000..db2e0487d6
--- /dev/null
+++ b/sysdeps/ieee754/flt-32/s_roundevenf.c
@@ -0,0 +1,68 @@
+/* Round to nearest integer value, rounding halfway cases to even.
+   flt-32 version.
+   Copyright (C) 2016 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 <stdint.h>
+
+#define BIAS 0x7f
+#define MANT_DIG 24
+#define MAX_EXP (2 * BIAS + 1)
+
+float
+roundevenf (float x)
+{
+  uint32_t ix, ux;
+  GET_FLOAT_WORD (ix, x);
+  ux = ix & 0x7fffffff;
+  int exponent = ux >> (MANT_DIG - 1);
+  if (exponent >= BIAS + MANT_DIG - 1)
+    {
+      /* Integer, infinity or NaN.  */
+      if (exponent == MAX_EXP)
+	/* Infinity or NaN; quiet signaling NaNs.  */
+	return x + x;
+      else
+	return x;
+    }
+  else if (exponent >= BIAS)
+    {
+      /* At least 1; not necessarily an integer.  Locate the bits with
+	 exponents 0 and -1 (when the unbiased exponent is 0, the bit
+	 with exponent 0 is implicit, but as the bias is odd it is OK
+	 to take it from the low bit of the exponent).  */
+      int int_pos = (BIAS + MANT_DIG - 1) - exponent;
+      int half_pos = int_pos - 1;
+      uint32_t half_bit = 1U << half_pos;
+      uint32_t int_bit = 1U << int_pos;
+      if ((ix & (int_bit | (half_bit - 1))) != 0)
+	/* Carry into the exponent works correctly.  No need to test
+	   whether HALF_BIT is set.  */
+	ix += half_bit;
+      ix &= ~(int_bit - 1);
+    }
+  else if (exponent == BIAS - 1 && ux > 0x3f000000)
+    /* Interval (0.5, 1).  */
+    ix = (ix & 0x80000000) | 0x3f800000;
+  else
+    /* Rounds to 0.  */
+    ix &= 0x80000000;
+  SET_FLOAT_WORD (x, ix);
+  return x;
+}
diff --git a/sysdeps/ieee754/ldbl-128/s_roundevenl.c b/sysdeps/ieee754/ldbl-128/s_roundevenl.c
new file mode 100644
index 0000000000..de042acf2d
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/s_roundevenl.c
@@ -0,0 +1,102 @@
+/* Round to nearest integer value, rounding halfway cases to even.
+   ldbl-128 version.
+   Copyright (C) 2016 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 <stdint.h>
+
+#define BIAS 0x3fff
+#define MANT_DIG 113
+#define MAX_EXP (2 * BIAS + 1)
+
+_Float128
+roundevenl (_Float128 x)
+{
+  uint64_t hx, lx, uhx;
+  GET_LDOUBLE_WORDS64 (hx, lx, x);
+  uhx = hx & 0x7fffffffffffffffULL;
+  int exponent = uhx >> (MANT_DIG - 1 - 64);
+  if (exponent >= BIAS + MANT_DIG - 1)
+    {
+      /* Integer, infinity or NaN.  */
+      if (exponent == MAX_EXP)
+	/* Infinity or NaN; quiet signaling NaNs.  */
+	return x + x;
+      else
+	return x;
+    }
+  else if (exponent >= BIAS + MANT_DIG - 64)
+    {
+      /* Not necessarily an integer; integer bit is in low word.
+	 Locate the bits with exponents 0 and -1.  */
+      int int_pos = (BIAS + MANT_DIG - 1) - exponent;
+      int half_pos = int_pos - 1;
+      uint64_t half_bit = 1ULL << half_pos;
+      uint64_t int_bit = 1ULL << int_pos;
+      if ((lx & (int_bit | (half_bit - 1))) != 0)
+	{
+	  /* Carry into the exponent works correctly.  No need to test
+	     whether HALF_BIT is set.  */
+	  lx += half_bit;
+	  hx += lx < half_bit;
+	}
+      lx &= ~(int_bit - 1);
+    }
+  else if (exponent == BIAS + MANT_DIG - 65)
+    {
+      /* Not necessarily an integer; integer bit is bottom of high
+	 word, half bit is top of low word.  */
+      if (((hx & 1) | (lx & 0x7fffffffffffffffULL)) != 0)
+	{
+	  lx += 0x8000000000000000ULL;
+	  hx += lx < 0x8000000000000000ULL;
+	}
+      lx = 0;
+    }
+  else if (exponent >= BIAS)
+    {
+      /* At least 1; not necessarily an integer, integer bit and half
+	 bit are in the high word.  Locate the bits with exponents 0
+	 and -1 (when the unbiased exponent is 0, the bit with
+	 exponent 0 is implicit, but as the bias is odd it is OK to
+	 take it from the low bit of the exponent).  */
+      int int_pos = (BIAS + MANT_DIG - 65) - exponent;
+      int half_pos = int_pos - 1;
+      uint64_t half_bit = 1ULL << half_pos;
+      uint64_t int_bit = 1ULL << int_pos;
+      if (((hx & (int_bit | (half_bit - 1))) | lx) != 0)
+	hx += half_bit;
+      hx &= ~(int_bit - 1);
+      lx = 0;
+    }
+  else if (exponent == BIAS - 1 && (uhx > 0x3ffe000000000000ULL || lx != 0))
+    {
+      /* Interval (0.5, 1).  */
+      hx = (hx & 0x8000000000000000ULL) | 0x3fff000000000000ULL;
+      lx = 0;
+    }
+  else
+    {
+      /* Rounds to 0.  */
+      hx &= 0x8000000000000000ULL;
+      lx = 0;
+    }
+  SET_LDOUBLE_WORDS64 (x, hx, lx);
+  return x;
+}
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_roundevenl.c b/sysdeps/ieee754/ldbl-128ibm/s_roundevenl.c
new file mode 100644
index 0000000000..cd91d3905c
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_roundevenl.c
@@ -0,0 +1,69 @@
+/* Round to nearest integer value, rounding halfway cases to even.
+   ldbl-128ibm version.
+   Copyright (C) 2016 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>
+
+long double
+roundevenl (long double x)
+{
+  double xh, xl, hi;
+
+  ldbl_unpack (x, &xh, &xl);
+
+  if (xh != 0 && isfinite (xh))
+    {
+      hi = roundeven (xh);
+      if (hi != xh)
+	{
+	  /* The high part is not an integer; the low part only
+	     affects the result if the high part is exactly half way
+	     between two integers and the low part is nonzero in the
+	     opposite direction to the rounding of the high part.  */
+	  double diff = hi - xh;
+	  if (fabs (diff) == 0.5)
+	    {
+	      if (xl < 0 && diff > 0)
+		xh = hi - 1;
+	      else if (xl > 0 && diff < 0)
+		xh = hi + 1;
+	      else
+		xh = hi;
+	    }
+	  else
+	    xh = hi;
+	  xl = 0;
+	}
+      else
+	{
+	  /* The high part is a nonzero integer.  Rounding the low
+	     part to nearest, ties round to even, is always correct,
+	     as a high part that is an odd integer together with a low
+	     part with magnitude 0.5 is not a valid long double.  */
+	  xl = roundeven (xl);
+	  xh = hi;
+	  ldbl_canonicalize_int (&xh, &xl);
+	}
+    }
+  else
+    /* Quiet signaling NaN arguments.  */
+    xh += xh;
+
+  return ldbl_pack (xh, xl);
+}
diff --git a/sysdeps/ieee754/ldbl-96/s_roundevenl.c b/sysdeps/ieee754/ldbl-96/s_roundevenl.c
new file mode 100644
index 0000000000..f635b1f683
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-96/s_roundevenl.c
@@ -0,0 +1,124 @@
+/* Round to nearest integer value, rounding halfway cases to even.
+   ldbl-96 version.
+   Copyright (C) 2016 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 <stdint.h>
+
+#define BIAS 0x3fff
+#define MANT_DIG 64
+#define MAX_EXP (2 * BIAS + 1)
+
+long double
+roundevenl (long double x)
+{
+  uint16_t se;
+  uint32_t hx, lx;
+  GET_LDOUBLE_WORDS (se, hx, lx, x);
+  int exponent = se & 0x7fff;
+  if (exponent >= BIAS + MANT_DIG - 1)
+    {
+      /* Integer, infinity or NaN.  */
+      if (exponent == MAX_EXP)
+	/* Infinity or NaN; quiet signaling NaNs.  */
+	return x + x;
+      else
+	return x;
+    }
+  else if (exponent >= BIAS + MANT_DIG - 32)
+    {
+      /* Not necessarily an integer; integer bit is in low word.
+	 Locate the bits with exponents 0 and -1.  */
+      int int_pos = (BIAS + MANT_DIG - 1) - exponent;
+      int half_pos = int_pos - 1;
+      uint32_t half_bit = 1U << half_pos;
+      uint32_t int_bit = 1U << int_pos;
+      if ((lx & (int_bit | (half_bit - 1))) != 0)
+	{
+	  /* No need to test whether HALF_BIT is set.  */
+	  lx += half_bit;
+	  if (lx < half_bit)
+	    {
+	      hx++;
+	      if (hx == 0)
+		{
+		  hx = 0x80000000;
+		  se++;
+		}
+	    }
+	}
+      lx &= ~(int_bit - 1);
+    }
+  else if (exponent == BIAS + MANT_DIG - 33)
+    {
+      /* Not necessarily an integer; integer bit is bottom of high
+	 word, half bit is top of low word.  */
+      if (((hx & 1) | (lx & 0x7fffffff)) != 0)
+	{
+	  lx += 0x80000000;
+	  if (lx < 0x80000000)
+	    {
+	      hx++;
+	      if (hx == 0)
+		{
+		  hx = 0x80000000;
+		  se++;
+		}
+	    }
+	}
+      lx = 0;
+    }
+  else if (exponent >= BIAS)
+    {
+      /* At least 1; not necessarily an integer, integer bit and half
+	 bit are in the high word.  Locate the bits with exponents 0
+	 and -1.  */
+      int int_pos = (BIAS + MANT_DIG - 33) - exponent;
+      int half_pos = int_pos - 1;
+      uint32_t half_bit = 1U << half_pos;
+      uint32_t int_bit = 1U << int_pos;
+      if (((hx & (int_bit | (half_bit - 1))) | lx) != 0)
+	{
+	  hx += half_bit;
+	  if (hx < half_bit)
+	    {
+	      hx = 0x80000000;
+	      se++;
+	    }
+	}
+      hx &= ~(int_bit - 1);
+      lx = 0;
+    }
+  else if (exponent == BIAS - 1 && (hx > 0x80000000 || lx != 0))
+    {
+      /* Interval (0.5, 1).  */
+      se = (se & 0x8000) | 0x3fff;
+      hx = 0x80000000;
+      lx = 0;
+    }
+  else
+    {
+      /* Rounds to 0.  */
+      se &= 0x8000;
+      hx = 0;
+      lx = 0;
+    }
+  SET_LDOUBLE_WORDS (x, se, hx, lx);
+  return x;
+}
diff --git a/sysdeps/ieee754/ldbl-opt/Makefile b/sysdeps/ieee754/ldbl-opt/Makefile
index 99aa6c6e0b..006d0d59ee 100644
--- a/sysdeps/ieee754/ldbl-opt/Makefile
+++ b/sysdeps/ieee754/ldbl-opt/Makefile
@@ -43,7 +43,8 @@ libnldbl-calls = asprintf dprintf fprintf fscanf fwprintf fwscanf iovfscanf \
 		 isoc99_wscanf isoc99_fwscanf isoc99_swscanf \
 		 isoc99_vwscanf isoc99_vfwscanf isoc99_vswscanf \
 		 nextup nextdown totalorder totalordermag getpayload \
-		 canonicalize setpayload setpayloadsig llogb fmaxmag fminmag
+		 canonicalize setpayload setpayloadsig llogb fmaxmag fminmag \
+		 roundeven
 libnldbl-routines = $(libnldbl-calls:%=nldbl-%)
 libnldbl-inhibit-o = $(object-suffixes)
 libnldbl-static-only-routines = $(libnldbl-routines)
@@ -138,6 +139,7 @@ CFLAGS-nldbl-remainder.c = -fno-builtin-remainderl -fno-builtin-dreml
 CFLAGS-nldbl-remquo.c = -fno-builtin-remquol
 CFLAGS-nldbl-rint.c = -fno-builtin-rintl
 CFLAGS-nldbl-round.c = -fno-builtin-roundl
+CFLAGS-nldbl-roundeven.c = -fno-builtin-roundevenl
 CFLAGS-nldbl-scalb.c = -fno-builtin-scalbl
 CFLAGS-nldbl-scalbln.c = -fno-builtin-scalblnl
 CFLAGS-nldbl-scalbn.c = -fno-builtin-scalbnl
diff --git a/sysdeps/ieee754/ldbl-opt/nldbl-roundeven.c b/sysdeps/ieee754/ldbl-opt/nldbl-roundeven.c
new file mode 100644
index 0000000000..cd52e7376f
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-opt/nldbl-roundeven.c
@@ -0,0 +1,26 @@
+/* Compatibility routine for IEEE double as long double for roundeven.
+   Copyright (C) 2016 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 "nldbl-compat.h"
+
+double
+attribute_hidden
+roundevenl (double x)
+{
+  return roundeven (x);
+}