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-rw-r--r--sysdeps/ieee754/cabs.c4
-rw-r--r--sysdeps/ieee754/hypot.c197
-rw-r--r--sysdeps/ieee754/ieee754.h6
3 files changed, 205 insertions, 2 deletions
diff --git a/sysdeps/ieee754/cabs.c b/sysdeps/ieee754/cabs.c
index 6b0d4c4cde..eed81ece58 100644
--- a/sysdeps/ieee754/cabs.c
+++ b/sysdeps/ieee754/cabs.c
@@ -89,6 +89,8 @@ static char sccsid[] = "@(#)cabs.c 5.6 (Berkeley) 10/9/90";
*/
#include "mathimpl.h"
+#if 0 /* Moved to separate file. */
+
vc(r2p1hi, 2.4142135623730950345E0 ,8279,411a,ef32,99fc, 2, .9A827999FCEF32)
vc(r2p1lo, 1.4349369327986523769E-17 ,597d,2484,754b,89b3, -55, .84597D89B3754B)
vc(sqrt2, 1.4142135623730950622E0 ,04f3,40b5,de65,33f9, 1, .B504F333F9DE65)
@@ -157,6 +159,8 @@ double x, y;
else return(copysign(y,one)); /* y is INF */
}
+#endif /* 0 */
+
/* CABS(Z)
* RETURN THE ABSOLUTE VALUE OF THE COMPLEX NUMBER Z = X + iY
* DOUBLE PRECISION (VAX D format 56 bits, IEEE DOUBLE 53 BITS)
diff --git a/sysdeps/ieee754/hypot.c b/sysdeps/ieee754/hypot.c
new file mode 100644
index 0000000000..cdc2ed02b9
--- /dev/null
+++ b/sysdeps/ieee754/hypot.c
@@ -0,0 +1,197 @@
+/*
+ * Copyright (c) 1985 Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+/* HYPOT(X,Y)
+ * RETURN THE SQUARE ROOT OF X^2 + Y^2 WHERE Z=X+iY
+ * DOUBLE PRECISION (VAX D format 56 bits, IEEE DOUBLE 53 BITS)
+ * CODED IN C BY K.C. NG, 11/28/84;
+ * REVISED BY K.C. NG, 7/12/85.
+ *
+ * Required system supported functions :
+ * copysign(x,y)
+ * finite(x)
+ * scalb(x,N)
+ * sqrt(x)
+ *
+ * Method :
+ * 1. replace x by |x| and y by |y|, and swap x and
+ * y if y > x (hence x is never smaller than y).
+ * 2. Hypot(x,y) is computed by:
+ * Case I, x/y > 2
+ *
+ * y
+ * hypot = x + -----------------------------
+ * 2
+ * sqrt ( 1 + [x/y] ) + x/y
+ *
+ * Case II, x/y <= 2
+ * y
+ * hypot = x + --------------------------------------------------
+ * 2
+ * [x/y] - 2
+ * (sqrt(2)+1) + (x-y)/y + -----------------------------
+ * 2
+ * sqrt ( 1 + [x/y] ) + sqrt(2)
+ *
+ *
+ *
+ * Special cases:
+ * hypot(x,y) is INF if x or y is +INF or -INF; else
+ * hypot(x,y) is NAN if x or y is NAN.
+ *
+ * Accuracy:
+ * hypot(x,y) returns the sqrt(x^2+y^2) with error less than 1 ulps (units
+ * in the last place). See Kahan's "Interval Arithmetic Options in the
+ * Proposed IEEE Floating Point Arithmetic Standard", Interval Mathematics
+ * 1980, Edited by Karl L.E. Nickel, pp 99-128. (A faster but less accurate
+ * code follows in comments.) In a test run with 500,000 random arguments
+ * on a VAX, the maximum observed error was .959 ulps.
+ *
+ * Constants:
+ * The hexadecimal values are the intended ones for the following constants.
+ * The decimal values may be used, provided that the compiler will convert
+ * from decimal to binary accurately enough to produce the hexadecimal values
+ * shown.
+ */
+#include "mathimpl.h"
+
+vc(r2p1hi, 2.4142135623730950345E0 ,8279,411a,ef32,99fc, 2, .9A827999FCEF32)
+vc(r2p1lo, 1.4349369327986523769E-17 ,597d,2484,754b,89b3, -55, .84597D89B3754B)
+vc(sqrt2, 1.4142135623730950622E0 ,04f3,40b5,de65,33f9, 1, .B504F333F9DE65)
+
+ic(r2p1hi, 2.4142135623730949234E0 , 1, 1.3504F333F9DE6)
+ic(r2p1lo, 1.2537167179050217666E-16 , -53, 1.21165F626CDD5)
+ic(sqrt2, 1.4142135623730951455E0 , 0, 1.6A09E667F3BCD)
+
+#ifdef vccast
+#define r2p1hi vccast(r2p1hi)
+#define r2p1lo vccast(r2p1lo)
+#define sqrt2 vccast(sqrt2)
+#endif
+
+double
+hypot(x,y)
+double x, y;
+{
+ static const double zero=0, one=1,
+ small=1.0E-18; /* fl(1+small)==1 */
+ static const ibig=30; /* fl(1+2**(2*ibig))==1 */
+ double t,r;
+ int exp;
+
+ if(finite(x))
+ if(finite(y))
+ {
+ x=copysign(x,one);
+ y=copysign(y,one);
+ if(y > x)
+ { t=x; x=y; y=t; }
+ if(x == zero) return(zero);
+ if(y == zero) return(x);
+ exp= logb(x);
+ if(exp-(int)logb(y) > ibig )
+ /* raise inexact flag and return |x| */
+ { one+small; return(x); }
+
+ /* start computing sqrt(x^2 + y^2) */
+ r=x-y;
+ if(r>y) { /* x/y > 2 */
+ r=x/y;
+ r=r+sqrt(one+r*r); }
+ else { /* 1 <= x/y <= 2 */
+ r/=y; t=r*(r+2.0);
+ r+=t/(sqrt2+sqrt(2.0+t));
+ r+=r2p1lo; r+=r2p1hi; }
+
+ r=y/r;
+ return(x+r);
+
+ }
+
+ else if(y==y) /* y is +-INF */
+ return(copysign(y,one));
+ else
+ return(y); /* y is NaN and x is finite */
+
+ else if(x==x) /* x is +-INF */
+ return (copysign(x,one));
+ else if(finite(y))
+ return(x); /* x is NaN, y is finite */
+#if !defined(vax)&&!defined(tahoe)
+ else if(y!=y) return(y); /* x and y is NaN */
+#endif /* !defined(vax)&&!defined(tahoe) */
+ else return(copysign(y,one)); /* y is INF */
+}
+
+/* A faster but less accurate version of cabs(x,y) */
+#if 0
+double hypot(x,y)
+double x, y;
+{
+ static const double zero=0, one=1;
+ small=1.0E-18; /* fl(1+small)==1 */
+ static const ibig=30; /* fl(1+2**(2*ibig))==1 */
+ double temp;
+ int exp;
+
+ if(finite(x))
+ if(finite(y))
+ {
+ x=copysign(x,one);
+ y=copysign(y,one);
+ if(y > x)
+ { temp=x; x=y; y=temp; }
+ if(x == zero) return(zero);
+ if(y == zero) return(x);
+ exp= logb(x);
+ x=scalb(x,-exp);
+ if(exp-(int)logb(y) > ibig )
+ /* raise inexact flag and return |x| */
+ { one+small; return(scalb(x,exp)); }
+ else y=scalb(y,-exp);
+ return(scalb(sqrt(x*x+y*y),exp));
+ }
+
+ else if(y==y) /* y is +-INF */
+ return(copysign(y,one));
+ else
+ return(y); /* y is NaN and x is finite */
+
+ else if(x==x) /* x is +-INF */
+ return (copysign(x,one));
+ else if(finite(y))
+ return(x); /* x is NaN, y is finite */
+ else if(y!=y) return(y); /* x and y is NaN */
+ else return(copysign(y,one)); /* y is INF */
+}
+#endif
diff --git a/sysdeps/ieee754/ieee754.h b/sysdeps/ieee754/ieee754.h
index 9cc6f14707..632564e330 100644
--- a/sysdeps/ieee754/ieee754.h
+++ b/sysdeps/ieee754/ieee754.h
@@ -135,14 +135,16 @@ union ieee854_long_double
unsigned int negative:1;
unsigned int exponent:15;
unsigned int empty:16;
+ unsigned int one:1;
unsigned int quiet_nan:1;
- unsigned int mantissa0:31;
+ unsigned int mantissa0:30;
unsigned int mantissa1:32;
#endif
#if __BYTE_ORDER == __LITTLE_ENDIAN
unsigned int mantissa1:32;
- unsigned int mantissa0:31;
+ unsigned int mantissa0:30;
unsigned int quiet_nan:1;
+ unsigned int one:1
unsigned int exponent:15;
unsigned int negative:1;
unsigned int empty:16;
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-19 18:14:23 +0000