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Diffstat (limited to 'sysdeps/ieee754/dbl-64/halfulp.c')
-rw-r--r--sysdeps/ieee754/dbl-64/halfulp.c52
1 files changed, 25 insertions, 27 deletions
diff --git a/sysdeps/ieee754/dbl-64/halfulp.c b/sysdeps/ieee754/dbl-64/halfulp.c
index 7901ec4e36..929ca91c50 100644
--- a/sysdeps/ieee754/dbl-64/halfulp.c
+++ b/sysdeps/ieee754/dbl-64/halfulp.c
@@ -5,9 +5,9 @@
*
* This program 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 of the License, or
+ * the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
- *
+ *
* This program 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
@@ -15,12 +15,12 @@
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
/************************************************************************/
/* */
-/* MODULE_NAME:halfulp.c */
-/* */
+/* MODULE_NAME:halfulp.c */
+/* */
/* FUNCTIONS:halfulp */
/* FILES NEEDED: mydefs.h dla.h endian.h */
/* uroot.c */
@@ -35,11 +35,11 @@
/*3. if x can be represented by x=2**n for some integer n. */
/************************************************************************/
-#include "endian.h"
+#include "endian.h"
#include "mydefs.h"
#include "dla.h"
-double usqrt(double x);
+double __ieee754_sqrt(double x);
int4 tab54[32] = {
262143, 11585, 1782, 511, 210, 107, 63, 42,
@@ -48,17 +48,17 @@ int4 tab54[32] = {
3, 3, 3, 3, 3, 3, 3, 3 };
-double halfulp(double x, double y)
+double __halfulp(double x, double y)
{
mynumber v;
double z,u,uu,j1,j2,j3,j4,j5;
int4 k,l,m,n;
if (y <= 0) { /*if power is negative or zero */
v.x = y;
- if (v.i[LOW_HALF] != 0) return -10.0;
+ if (v.i[LOW_HALF] != 0) return -10.0;
v.x = x;
- if (v.i[LOW_HALF] != 0) return -10.0;
- if ((v.i[HIGH_HALF]&0x000fffff) != 0) return -10; /* if x =2 ^ n */
+ if (v.i[LOW_HALF] != 0) return -10.0;
+ if ((v.i[HIGH_HALF]&0x000fffff) != 0) return -10; /* if x =2 ^ n */
k = ((v.i[HIGH_HALF]&0x7fffffff)>>20)-1023; /* find this n */
z = (double) k;
return (z*y == -1075.0)?0: -10.0;
@@ -66,19 +66,19 @@ double halfulp(double x, double y)
/* if y > 0 */
v.x = y;
if (v.i[LOW_HALF] != 0) return -10.0;
-
+
v.x=x;
- /* case where x = 2**n for some integer n */
+ /* case where x = 2**n for some integer n */
if (((v.i[HIGH_HALF]&0x000fffff)|v.i[LOW_HALF]) == 0) {
k=(v.i[HIGH_HALF]>>20)-1023;
return (((double) k)*y == -1075.0)?0:-10.0;
- }
-
+ }
+
v.x = y;
k = v.i[HIGH_HALF];
m = k<<12;
l = 0;
- while (m)
+ while (m)
{m = m<<1; l++; }
n = (k&0x000fffff)|0x00100000;
n = n>>(20-l); /* n is the odd integer of y */
@@ -88,19 +88,19 @@ double halfulp(double x, double y)
if (n > 34) return -10.0;
k = -k;
if (k>5) return -10.0;
-
+
/* now treat x */
while (k>0) {
- z = usqrt(x);
+ z = __ieee754_sqrt(x);
EMULV(z,z,u,uu,j1,j2,j3,j4,j5);
if (((u-x)+uu) != 0) break;
x = z;
k--;
}
- if (k) return -10.0;
-
+ if (k) return -10.0;
+
/* it is impossible that n == 2, so the mantissa of x must be short */
-
+
v.x = x;
if (v.i[LOW_HALF]) return -10.0;
k = v.i[HIGH_HALF];
@@ -109,16 +109,14 @@ double halfulp(double x, double y)
while (m) {m = m<<1; l++; }
m = (k&0x000fffff)|0x00100000;
m = m>>(20-l); /* m is the odd integer of x */
-
+
/* now check whether the length of m**n is at most 54 bits */
-
+
if (m > tab54[n-3]) return -10.0;
-
+
/* yes, it is - now compute x**n by simple multiplications */
-
+
u = x;
for (k=1;k<n;k++) u = u*x;
return u;
}
-
-