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11210 libm should be cstyle(1ONBLD) clean
@@ -20,18 +20,19 @@
*/
/*
* Copyright 2011 Nexenta Systems, Inc. All rights reserved.
*/
+
/*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma weak __cacos = cacos
-/* INDENT OFF */
+
/*
* dcomplex cacos(dcomplex z);
*
* Alogrithm
* (based on T.E.Hull, Thomas F. Fairgrieve and Ping Tak Peter Tang's
@@ -188,18 +189,15 @@
* = 0.5*log(1+2y(y+sqrt(1+y^2)));
* = 0.5*log1p(2y(y+A));
*
* cacos(z) = acos(B) - i sign(y) log (A + sqrt(A*A-1)),
*/
-/* INDENT ON */
#include "libm.h"
#include "complex_wrapper.h"
-/* INDENT OFF */
-static const double
- zero = 0.0,
+static const double zero = 0.0,
one = 1.0,
E = 1.11022302462515654042e-16, /* 2**-53 */
ln2 = 6.93147180559945286227e-01,
pi = 3.1415926535897931159979634685,
pi_l = 1.224646799147353177e-16,
@@ -211,14 +209,15 @@
pi3_4_l = 9.184850993605148829195e-17,
Foursqrtu = 5.96667258496016539463e-154, /* 2**(-509) */
Acrossover = 1.5,
Bcrossover = 0.6417,
half = 0.5;
-/* INDENT ON */
+
dcomplex
-cacos(dcomplex z) {
+cacos(dcomplex z)
+{
double x, y, t, R, S, A, Am1, B, y2, xm1, xp1, Apx;
int ix, iy, hx, hy;
unsigned lx, ly;
dcomplex ans;
@@ -242,10 +241,11 @@
/* |y| is inf or NaN */
if (iy >= 0x7ff00000) {
if (ISINF(iy, ly)) { /* cacos(x + i inf) = pi/2 - i inf */
D_IM(ans) = -y;
+
if (ix < 0x7ff00000) {
D_RE(ans) = pi_2 + pi_2_l;
} else if (ISINF(ix, lx)) {
if (hx >= 0)
D_RE(ans) = pi_4 + pi_4_l;
@@ -254,81 +254,88 @@
} else {
D_RE(ans) = x;
}
} else { /* cacos(x + i NaN) = NaN + i NaN */
D_RE(ans) = y + x;
+
if (ISINF(ix, lx))
D_IM(ans) = -fabs(x);
else
D_IM(ans) = y;
}
+
return (ans);
}
x = fabs(x);
y = fabs(y);
/* x is inf or NaN */
if (ix >= 0x7ff00000) { /* x is inf or NaN */
if (ISINF(ix, lx)) { /* x is INF */
D_IM(ans) = -x;
+
if (iy >= 0x7ff00000) {
if (ISINF(iy, ly)) {
- /* INDENT OFF */
- /* cacos(inf + i inf) = pi/4 - i inf */
- /* cacos(-inf+ i inf) =3pi/4 - i inf */
- /* INDENT ON */
+ /*
+ * cacos(inf + i inf) = pi/4 - i inf
+ * cacos(-inf+ i inf) =3pi/4 - i inf
+ */
if (hx >= 0)
D_RE(ans) = pi_4 + pi_4_l;
else
D_RE(ans) = pi3_4 + pi3_4_l;
- } else
- /* INDENT OFF */
- /* cacos(inf + i NaN) = NaN - i inf */
- /* INDENT ON */
+ } else {
+ /*
+ * cacos(inf + i NaN) = NaN - i inf
+ */
D_RE(ans) = y + y;
+ }
} else
- /* INDENT OFF */
- /* cacos(inf + iy ) = 0 - i inf */
- /* cacos(-inf+ iy ) = pi - i inf */
- /* INDENT ON */
- if (hx >= 0)
+ /*
+ * cacos(inf + iy ) = 0 - i inf
+ * cacos(-inf+ iy ) = pi - i inf
+ */
+ if (hx >= 0) {
D_RE(ans) = zero;
- else
+ } else {
D_RE(ans) = pi + pi_l;
+ }
} else { /* x is NaN */
- /* INDENT OFF */
+
/*
* cacos(NaN + i inf) = NaN - i inf
* cacos(NaN + i y ) = NaN + i NaN
* cacos(NaN + i NaN) = NaN + i NaN
*/
- /* INDENT ON */
D_RE(ans) = x + y;
- if (iy >= 0x7ff00000) {
+
+ if (iy >= 0x7ff00000)
D_IM(ans) = -y;
- } else {
+ else
D_IM(ans) = x;
}
- }
+
if (hy < 0)
D_IM(ans) = -D_IM(ans);
+
return (ans);
}
if ((iy | ly) == 0) { /* region 1: y=0 */
if (ix < 0x3ff00000) { /* |x| < 1 */
D_RE(ans) = acos(x);
D_IM(ans) = zero;
} else {
D_RE(ans) = zero;
- if (ix >= 0x43500000) /* |x| >= 2**54 */
+
+ if (ix >= 0x43500000) { /* |x| >= 2**54 */
D_IM(ans) = ln2 + log(x);
- else if (ix >= 0x3ff80000) /* x > Acrossover */
+ } else if (ix >= 0x3ff80000) { /* x > Acrossover */
D_IM(ans) = log(x + sqrt((x - one) * (x +
one)));
- else {
+ } else {
xm1 = x - one;
D_IM(ans) = log1p(xm1 + sqrt(xm1 * (x + one)));
}
}
} else if (y <= E * fabs(x - one)) { /* region 2: y < tiny*|x-1| */
@@ -339,10 +346,11 @@
D_RE(ans) = y / x;
D_IM(ans) = ln2 + log(x);
} else {
t = sqrt((x - one) * (x + one));
D_RE(ans) = y / t;
+
if (ix >= 0x3ff80000) /* x > Acrossover */
D_IM(ans) = log(x + t);
else
D_IM(ans) = log1p((x - one) + t);
}
@@ -360,10 +368,11 @@
D_IM(ans) = ln2 + log(y) + half * log1p(t * t);
} else if (x < Foursqrtu) {
/* region 6: x is very small, < 4sqrt(min) */
D_RE(ans) = pi_2;
A = sqrt(one + y * y);
+
if (iy >= 0x3ff80000) /* if y > Acrossover */
D_IM(ans) = log(y + A);
else
D_IM(ans) = half * log1p((y + y) * (y + A));
} else { /* safe region */
@@ -372,33 +381,40 @@
xm1 = x - one;
R = sqrt(xp1 * xp1 + y2);
S = sqrt(xm1 * xm1 + y2);
A = half * (R + S);
B = x / A;
- if (B <= Bcrossover)
+
+ if (B <= Bcrossover) {
D_RE(ans) = acos(B);
- else { /* use atan and an accurate approx to a-x */
+ } else { /* use atan and an accurate approx to a-x */
Apx = A + x;
+
if (x <= one)
D_RE(ans) = atan(sqrt(half * Apx * (y2 / (R +
xp1) + (S - xm1))) / x);
else
D_RE(ans) = atan((y * sqrt(half * (Apx / (R +
xp1) + Apx / (S + xm1)))) / x);
}
+
if (A <= Acrossover) {
/* use log1p and an accurate approx to A-1 */
if (x < one)
Am1 = half * (y2 / (R + xp1) + y2 / (S - xm1));
else
Am1 = half * (y2 / (R + xp1) + (S + xm1));
+
D_IM(ans) = log1p(Am1 + sqrt(Am1 * (A + one)));
} else {
D_IM(ans) = log(A + sqrt(A * A - one));
}
}
+
if (hx < 0)
D_RE(ans) = pi - D_RE(ans);
+
if (hy >= 0)
D_IM(ans) = -D_IM(ans);
+
return (ans);
}