From 39e4d10ddeca3ffcc401cdbb6af690b50c10cc0c Mon Sep 17 00:00:00 2001
From: "Paul E. Murphy" <murphyp@linux.vnet.ibm.com>
Date: Mon, 8 Aug 2016 15:58:28 -0500
Subject: [PATCH 1/5] Merge common usage of mul_split function
A number of files share identical code for the
mul_split function.
This moves the duplicated function mul_split into its
own header, and refactors the fma usage into a single
selection macro. Likewise, mul_split when used by a
long double implementation is renamed mul_splitl for
clarity.
* sysdeps/ieee754/ldbl-128/gamma_productl.c:
(mul_split) Remove, rename as mul_splitl, remove
redundant float.h include, and include via mul_splitl.h
* sysdeps/ieee754/ldbl-128/lgamma_productl.c: Likewise.
* sysdeps/ieee754/ldbl-128/x2y2m1l.c: Likewise.
* sysdeps/ieee754/ldbl-96/gamma_product.c: Likewise.
* sysdeps/ieee754/ldbl-96/lgamma_product.c: Likewise.
* sysdeps/ieee754/ldbl-96/x2y2m1.c: Likewise.
* math/mul_splitl.h: New file.
* sysdeps/ieee754/dbl-64/gamma_product.c (mul_split):
Move into mul_split.h, and remove redundant float.h include.
* sysdeps/ieee754/dbl-64/lgamma_product.c: Likewise.
* sysdeps/ieee754/dbl-64/x2y2m1.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/s_fmal.c: Likewise.
* sysdeps/ieee754/ldbl-128ibm/x2y2m1.c: Likewise.
* math/mul_split.h: New file.
---
math/mul_split.h | 57 ++++++++++++++++++++++++++++++
math/mul_splitl.h | 57 ++++++++++++++++++++++++++++++
sysdeps/ieee754/dbl-64/gamma_product.c | 32 +----------------
sysdeps/ieee754/dbl-64/lgamma_product.c | 32 +----------------
sysdeps/ieee754/dbl-64/x2y2m1.c | 32 +----------------
sysdeps/ieee754/ldbl-128/gamma_productl.c | 34 ++----------------
sysdeps/ieee754/ldbl-128/lgamma_productl.c | 36 ++-----------------
sysdeps/ieee754/ldbl-128/x2y2m1l.c | 37 +++----------------
sysdeps/ieee754/ldbl-128ibm/s_fmal.c | 27 +-------------
sysdeps/ieee754/ldbl-128ibm/x2y2m1l.c | 32 +----------------
sysdeps/ieee754/ldbl-96/gamma_productl.c | 34 ++----------------
sysdeps/ieee754/ldbl-96/lgamma_productl.c | 36 ++-----------------
sysdeps/ieee754/ldbl-96/x2y2m1l.c | 36 ++-----------------
13 files changed, 136 insertions(+), 346 deletions(-)
create mode 100644 math/mul_split.h
create mode 100644 math/mul_splitl.h
new file mode 100644
@@ -0,0 +1,57 @@
+/* Compute full X * Y for double type.
+ Copyright (C) 2013-2016 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/>. */
+
+#ifndef _MUL_SPLIT_H
+#define _MUL_SPLIT_H
+
+#include <float.h>
+
+/* Choose an appropriate fused multiply-add function, if any. */
+#ifdef __FP_FAST_FMA
+# define __FMA __builtin_fma
+#elif defined FP_FAST_FMA
+# define __FMA __fma
+#endif
+
+/* Calculate X * Y exactly and store the result in *HI + *LO. It is
+ given that the values are small enough that no overflow occurs and
+ large enough (or zero) that no underflow occurs. */
+
+static void
+mul_split (double *hi, double *lo, double x, double y)
+{
+#ifdef __FMA
+ /* Fast built-in fused multiply-add. */
+ *hi = x * y;
+ *lo = __FMA (x, y, -*hi);
+#else
+ /* Apply Dekker's algorithm. */
+ *hi = x * y;
+# define C ((1 << (DBL_MANT_DIG + 1) / 2) + 1)
+ double x1 = x * C;
+ double y1 = y * C;
+# undef C
+ x1 = (x - x1) + x1;
+ y1 = (y - y1) + y1;
+ double x2 = x - x1;
+ double y2 = y - y1;
+ *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
+#endif
+}
+
+#endif /* _MUL_SPLIT_H */
new file mode 100644
@@ -0,0 +1,57 @@
+/* Compute full X * Y for long double type.
+ Copyright (C) 2013-2016 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/>. */
+
+#ifndef _MUL_SPLITL_H
+#define _MUL_SPLITL_H
+
+#include <float.h>
+
+/* Choose an appropriate fused multiply-add function, if any. */
+#ifdef __FP_FAST_FMAL
+# define __FMAL __builtin_fmal
+#elif defined FP_FAST_FMAL
+# define __FMAL __fmal
+#endif
+
+/* Calculate X * Y exactly and store the result in *HI + *LO. It is
+ given that the values are small enough that no overflow occurs and
+ large enough (or zero) that no underflow occurs. */
+
+static inline void
+mul_splitl (long double *hi, long double *lo, long double x, long double y)
+{
+#ifdef __FMAL
+ /* Fast library fused multiply-add, if supported. */
+ *hi = x * y;
+ *lo = __FMAL (x, y, -*hi);
+#else
+ /* Apply Dekker's algorithm. */
+ *hi = x * y;
+# define C ((1LL << (LDBL_MANT_DIG + 1) / 2) + 1)
+ long double x1 = x * C;
+ long double y1 = y * C;
+# undef C
+ x1 = (x - x1) + x1;
+ y1 = (y - y1) + y1;
+ long double x2 = x - x1;
+ long double y2 = y - y1;
+ *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
+#endif
+}
+
+#endif /* _MUL_SPLITL_H */
@@ -18,37 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
-
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static void
-mul_split (double *hi, double *lo, double x, double y)
-{
-#ifdef __FP_FAST_FMA
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fma (x, y, -*hi);
-#elif defined FP_FAST_FMA
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fma (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1 << (DBL_MANT_DIG + 1) / 2) + 1)
- double x1 = x * C;
- double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- double x2 = x - x1;
- double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
+#include <mul_split.h>
/* Compute the product of X + X_EPS, X + X_EPS + 1, ..., X + X_EPS + N
- 1, in the form R * (1 + *EPS) where the return value R is an
@@ -18,37 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
-
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static void
-mul_split (double *hi, double *lo, double x, double y)
-{
-#ifdef __FP_FAST_FMA
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fma (x, y, -*hi);
-#elif defined FP_FAST_FMA
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fma (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1 << (DBL_MANT_DIG + 1) / 2) + 1)
- double x1 = x * C;
- double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- double x2 = x - x1;
- double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
+#include <mul_split.h>
/* Compute the product of 1 + (T / (X + X_EPS)), 1 + (T / (X + X_EPS +
1)), ..., 1 + (T / (X + X_EPS + N - 1)), minus 1. X is such that
@@ -18,7 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
+#include <mul_split.h>
#include <stdlib.h>
/* Calculate X + Y exactly and store the result in *HI + *LO. It is
@@ -33,36 +33,6 @@ add_split (double *hi, double *lo, double x, double y)
*lo = (x - *hi) + y;
}
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static void
-mul_split (double *hi, double *lo, double x, double y)
-{
-#ifdef __FP_FAST_FMA
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fma (x, y, -*hi);
-#elif defined FP_FAST_FMA
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fma (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1 << (DBL_MANT_DIG + 1) / 2) + 1)
- double x1 = x * C;
- double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- double x2 = x - x1;
- double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
-
/* Compare absolute values of floating-point values pointed to by P
and Q for qsort. */
@@ -18,37 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
-
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static inline void
-mul_split (long double *hi, long double *lo, long double x, long double y)
-{
-#ifdef __FP_FAST_FMAL
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fmal (x, y, -*hi);
-#elif defined FP_FAST_FMAL
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fmal (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1LL << (LDBL_MANT_DIG + 1) / 2) + 1)
- long double x1 = x * C;
- long double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- long double x2 = x - x1;
- long double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
+#include <mul_splitl.h>
/* Compute the product of X + X_EPS, X + X_EPS + 1, ..., X + X_EPS + N
- 1, in the form R * (1 + *EPS) where the return value R is an
@@ -68,7 +38,7 @@ __gamma_productl (long double x, long double x_eps, int n, long double *eps)
{
*eps += x_eps / (x + i);
long double lo;
- mul_split (&ret, &lo, ret, x + i);
+ mul_splitl (&ret, &lo, ret, x + i);
*eps += lo / ret;
}
return ret;
@@ -18,37 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
-
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static void
-mul_split (long double *hi, long double *lo, long double x, long double y)
-{
-#ifdef __FP_FAST_FMAL
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fmal (x, y, -*hi);
-#elif defined FP_FAST_FMAL
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fmal (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1LL << (LDBL_MANT_DIG + 1) / 2) + 1)
- long double x1 = x * C;
- long double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- long double x2 = x - x1;
- long double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
+#include <mul_splitl.h>
/* Compute the product of 1 + (T / (X + X_EPS)), 1 + (T / (X + X_EPS +
1)), ..., 1 + (T / (X + X_EPS + N - 1)), minus 1. X is such that
@@ -65,11 +35,11 @@ __lgamma_productl (long double t, long double x, long double x_eps, int n)
long double xi = x + i;
long double quot = t / xi;
long double mhi, mlo;
- mul_split (&mhi, &mlo, quot, xi);
+ mul_splitl (&mhi, &mlo, quot, xi);
long double quot_lo = (t - mhi - mlo) / xi - t * x_eps / (xi * xi);
/* We want (1 + RET + RET_EPS) * (1 + QUOT + QUOT_LO) - 1. */
long double rhi, rlo;
- mul_split (&rhi, &rlo, ret, quot);
+ mul_splitl (&rhi, &rlo, ret, quot);
long double rpq = ret + quot;
long double rpq_eps = (ret - rpq) + quot;
long double nret = rpq + rhi;
@@ -18,9 +18,10 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
+#include <mul_splitl.h>
#include <stdlib.h>
+
/* Calculate X + Y exactly and store the result in *HI + *LO. It is
given that |X| >= |Y| and the values are small enough that no
overflow occurs. */
@@ -33,36 +34,6 @@ add_split (long double *hi, long double *lo, long double x, long double y)
*lo = (x - *hi) + y;
}
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static inline void
-mul_split (long double *hi, long double *lo, long double x, long double y)
-{
-#ifdef __FP_FAST_FMAL
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fmal (x, y, -*hi);
-#elif defined FP_FAST_FMAL
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fmal (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1LL << (LDBL_MANT_DIG + 1) / 2) + 1)
- long double x1 = x * C;
- long double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- long double x2 = x - x1;
- long double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
-
/* Compare absolute values of floating-point values pointed to by P
and Q for qsort. */
@@ -88,8 +59,8 @@ __x2y2m1l (long double x, long double y)
{
long double vals[5];
SET_RESTORE_ROUNDL (FE_TONEAREST);
- mul_split (&vals[1], &vals[0], x, x);
- mul_split (&vals[3], &vals[2], y, y);
+ mul_splitl (&vals[1], &vals[0], x, x);
+ mul_splitl (&vals[3], &vals[2], y, y);
vals[4] = -1.0L;
qsort (vals, 5, sizeof (long double), compare);
/* Add up the values so that each element of VALS has absolute value
@@ -22,6 +22,7 @@
#include <math.h>
#include <math_private.h>
#include <math_ldbl_opt.h>
+#include <mul_split.h>
#include <stdlib.h>
/* Calculate X + Y exactly and store the result in *HI + *LO. It is
@@ -36,32 +37,6 @@ add_split (double *hi, double *lo, double x, double y)
*lo = (x - *hi) + y;
}
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static void
-mul_split (double *hi, double *lo, double x, double y)
-{
-#ifdef __FP_FAST_FMA
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fma (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1 << (DBL_MANT_DIG + 1) / 2) + 1)
- double x1 = x * C;
- double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- double x2 = x - x1;
- double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
-
/* Value with extended range, used in intermediate computations. */
typedef struct
{
@@ -18,7 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
+#include <mul_split.h>
#include <stdlib.h>
/* Calculate X + Y exactly and store the result in *HI + *LO. It is
@@ -33,36 +33,6 @@ add_split (double *hi, double *lo, double x, double y)
*lo = (x - *hi) + y;
}
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static inline void
-mul_split (double *hi, double *lo, double x, double y)
-{
-#ifdef __FP_FAST_FMA
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fma (x, y, -*hi);
-#elif defined FP_FAST_FMA
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fma (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1 << (DBL_MANT_DIG + 1) / 2) + 1)
- double x1 = x * C;
- double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- double x2 = x - x1;
- double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
-
/* Compare absolute values of floating-point values pointed to by P
and Q for qsort. */
@@ -18,37 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
-
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static inline void
-mul_split (long double *hi, long double *lo, long double x, long double y)
-{
-#ifdef __FP_FAST_FMAL
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fmal (x, y, -*hi);
-#elif defined FP_FAST_FMAL
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fmal (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1LL << (LDBL_MANT_DIG + 1) / 2) + 1)
- long double x1 = x * C;
- long double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- long double x2 = x - x1;
- long double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
+#include <mul_splitl.h>
/* Compute the product of X + X_EPS, X + X_EPS + 1, ..., X + X_EPS + N
- 1, in the form R * (1 + *EPS) where the return value R is an
@@ -68,7 +38,7 @@ __gamma_productl (long double x, long double x_eps, int n, long double *eps)
{
*eps += x_eps / (x + i);
long double lo;
- mul_split (&ret, &lo, ret, x + i);
+ mul_splitl (&ret, &lo, ret, x + i);
*eps += lo / ret;
}
return ret;
@@ -18,37 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
-
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static void
-mul_split (long double *hi, long double *lo, long double x, long double y)
-{
-#ifdef __FP_FAST_FMAL
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fmal (x, y, -*hi);
-#elif defined FP_FAST_FMAL
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fmal (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1LL << (LDBL_MANT_DIG + 1) / 2) + 1)
- long double x1 = x * C;
- long double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- long double x2 = x - x1;
- long double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
+#include <mul_splitl.h>
/* Compute the product of 1 + (T / (X + X_EPS)), 1 + (T / (X + X_EPS +
1)), ..., 1 + (T / (X + X_EPS + N - 1)), minus 1. X is such that
@@ -65,11 +35,11 @@ __lgamma_productl (long double t, long double x, long double x_eps, int n)
long double xi = x + i;
long double quot = t / xi;
long double mhi, mlo;
- mul_split (&mhi, &mlo, quot, xi);
+ mul_splitl (&mhi, &mlo, quot, xi);
long double quot_lo = (t - mhi - mlo) / xi - t * x_eps / (xi * xi);
/* We want (1 + RET + RET_EPS) * (1 + QUOT + QUOT_LO) - 1. */
long double rhi, rlo;
- mul_split (&rhi, &rlo, ret, quot);
+ mul_splitl (&rhi, &rlo, ret, quot);
long double rpq = ret + quot;
long double rpq_eps = (ret - rpq) + quot;
long double nret = rpq + rhi;
@@ -18,7 +18,7 @@
#include <math.h>
#include <math_private.h>
-#include <float.h>
+#include <mul_splitl.h>
#include <stdlib.h>
/* Calculate X + Y exactly and store the result in *HI + *LO. It is
@@ -33,36 +33,6 @@ add_split (long double *hi, long double *lo, long double x, long double y)
*lo = (x - *hi) + y;
}
-/* Calculate X * Y exactly and store the result in *HI + *LO. It is
- given that the values are small enough that no overflow occurs and
- large enough (or zero) that no underflow occurs. */
-
-static inline void
-mul_split (long double *hi, long double *lo, long double x, long double y)
-{
-#ifdef __FP_FAST_FMAL
- /* Fast built-in fused multiply-add. */
- *hi = x * y;
- *lo = __builtin_fmal (x, y, -*hi);
-#elif defined FP_FAST_FMAL
- /* Fast library fused multiply-add, compiler before GCC 4.6. */
- *hi = x * y;
- *lo = __fmal (x, y, -*hi);
-#else
- /* Apply Dekker's algorithm. */
- *hi = x * y;
-# define C ((1LL << (LDBL_MANT_DIG + 1) / 2) + 1)
- long double x1 = x * C;
- long double y1 = y * C;
-# undef C
- x1 = (x - x1) + x1;
- y1 = (y - y1) + y1;
- long double x2 = x - x1;
- long double y2 = y - y1;
- *lo = (((x1 * y1 - *hi) + x1 * y2) + x2 * y1) + x2 * y2;
-#endif
-}
-
/* Compare absolute values of floating-point values pointed to by P
and Q for qsort. */
@@ -88,8 +58,8 @@ __x2y2m1l (long double x, long double y)
{
long double vals[5];
SET_RESTORE_ROUNDL (FE_TONEAREST);
- mul_split (&vals[1], &vals[0], x, x);
- mul_split (&vals[3], &vals[2], y, y);
+ mul_splitl (&vals[1], &vals[0], x, x);
+ mul_splitl (&vals[3], &vals[2], y, y);
vals[4] = -1.0L;
qsort (vals, 5, sizeof (long double), compare);
/* Add up the values so that each element of VALS has absolute value
--
2.4.11