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Diffstat (limited to 'lib/mlibc/options/ansi/musl-generic-math/atan2l.c')
-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/atan2l.c85
1 files changed, 85 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/atan2l.c b/lib/mlibc/options/ansi/musl-generic-math/atan2l.c
new file mode 100644
index 0000000..f0937a9
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+++ b/lib/mlibc/options/ansi/musl-generic-math/atan2l.c
@@ -0,0 +1,85 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/e_atan2l.c */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunSoft, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ *
+ */
+/*
+ * See comments in atan2.c.
+ * Converted to long double by David Schultz <das@FreeBSD.ORG>.
+ */
+
+#include "libm.h"
+
+#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
+long double atan2l(long double y, long double x)
+{
+ return atan2(y, x);
+}
+#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
+#include "__invtrigl.h"
+
+long double atan2l(long double y, long double x)
+{
+ union ldshape ux, uy;
+ long double z;
+ int m, ex, ey;
+
+ if (isnan(x) || isnan(y))
+ return x+y;
+ if (x == 1)
+ return atanl(y);
+ ux.f = x;
+ uy.f = y;
+ ex = ux.i.se & 0x7fff;
+ ey = uy.i.se & 0x7fff;
+ m = 2*(ux.i.se>>15) | uy.i.se>>15;
+ if (y == 0) {
+ switch(m) {
+ case 0:
+ case 1: return y; /* atan(+-0,+anything)=+-0 */
+ case 2: return 2*pio2_hi; /* atan(+0,-anything) = pi */
+ case 3: return -2*pio2_hi; /* atan(-0,-anything) =-pi */
+ }
+ }
+ if (x == 0)
+ return m&1 ? -pio2_hi : pio2_hi;
+ if (ex == 0x7fff) {
+ if (ey == 0x7fff) {
+ switch(m) {
+ case 0: return pio2_hi/2; /* atan(+INF,+INF) */
+ case 1: return -pio2_hi/2; /* atan(-INF,+INF) */
+ case 2: return 1.5*pio2_hi; /* atan(+INF,-INF) */
+ case 3: return -1.5*pio2_hi; /* atan(-INF,-INF) */
+ }
+ } else {
+ switch(m) {
+ case 0: return 0.0; /* atan(+...,+INF) */
+ case 1: return -0.0; /* atan(-...,+INF) */
+ case 2: return 2*pio2_hi; /* atan(+...,-INF) */
+ case 3: return -2*pio2_hi; /* atan(-...,-INF) */
+ }
+ }
+ }
+ if (ex+120 < ey || ey == 0x7fff)
+ return m&1 ? -pio2_hi : pio2_hi;
+ /* z = atan(|y/x|) without spurious underflow */
+ if ((m&2) && ey+120 < ex) /* |y/x| < 0x1p-120, x<0 */
+ z = 0.0;
+ else
+ z = atanl(fabsl(y/x));
+ switch (m) {
+ case 0: return z; /* atan(+,+) */
+ case 1: return -z; /* atan(-,+) */
+ case 2: return 2*pio2_hi-(z-2*pio2_lo); /* atan(+,-) */
+ default: /* case 3 */
+ return (z-2*pio2_lo)-2*pio2_hi; /* atan(-,-) */
+ }
+}
+#endif