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authorRaghuram Subramani <raghus2247@gmail.com>2022-06-19 19:47:51 +0530
committerRaghuram Subramani <raghus2247@gmail.com>2022-06-19 19:47:51 +0530
commit4fd287655a72b9aea14cdac715ad5b90ed082ed2 (patch)
tree65d393bc0e699dd12d05b29ba568e04cea666207 /circuitpython/lib/libm/asinfacosf.c
parent0150f70ce9c39e9e6dd878766c0620c85e47bed0 (diff)
add circuitpython code
Diffstat (limited to 'circuitpython/lib/libm/asinfacosf.c')
-rw-r--r--circuitpython/lib/libm/asinfacosf.c130
1 files changed, 130 insertions, 0 deletions
diff --git a/circuitpython/lib/libm/asinfacosf.c b/circuitpython/lib/libm/asinfacosf.c
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+++ b/circuitpython/lib/libm/asinfacosf.c
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+/*****************************************************************************/
+/*****************************************************************************/
+// asinf from musl-0.9.15
+/*****************************************************************************/
+/*****************************************************************************/
+
+/* origin: FreeBSD /usr/src/lib/msun/src/e_asinf.c */
+/*
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+#include "libm.h"
+
+// dpgeorge: pio2 was double in original implementation of asinf
+static const float
+pio2_hi = 1.5707962513e+00f, /* 0x3fc90fda */
+pio2_lo = 7.5497894159e-08f; /* 0x33a22168 */
+
+static const float
+/* coefficients for R(x^2) */
+pS0 = 1.6666586697e-01f,
+pS1 = -4.2743422091e-02f,
+pS2 = -8.6563630030e-03f,
+qS1 = -7.0662963390e-01f;
+
+static float R(float z)
+{
+ float_t p, q;
+ p = z*(pS0+z*(pS1+z*pS2));
+ q = 1.0f+z*qS1;
+ return p/q;
+}
+
+float asinf(float x)
+{
+ // dpgeorge: s was double in original implementation
+ float s,z;
+ uint32_t hx,ix;
+
+ GET_FLOAT_WORD(hx, x);
+ ix = hx & 0x7fffffff;
+ if (ix >= 0x3f800000) { /* |x| >= 1 */
+ if (ix == 0x3f800000) /* |x| == 1 */
+ return x*pio2_hi + 0x1p-120f; /* asin(+-1) = +-pi/2 with inexact */
+ return 0/(x-x); /* asin(|x|>1) is NaN */
+ }
+ if (ix < 0x3f000000) { /* |x| < 0.5 */
+ /* if 0x1p-126 <= |x| < 0x1p-12, avoid raising underflow */
+ if (ix < 0x39800000 && ix >= 0x00800000)
+ return x;
+ return x + x*R(x*x);
+ }
+ /* 1 > |x| >= 0.5 */
+ z = (1 - fabsf(x))*0.5f;
+ s = sqrtf(z);
+ x = pio2_hi - (2*(s+s*R(z)) - pio2_lo); // dpgeorge: use pio2_hi and pio2_lo
+ if (hx >> 31)
+ return -x;
+ return x;
+}
+
+/*****************************************************************************/
+/*****************************************************************************/
+// acosf from musl-0.9.15
+/*****************************************************************************/
+/*****************************************************************************/
+
+/* origin: FreeBSD /usr/src/lib/msun/src/e_acosf.c */
+/*
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+float acosf(float x)
+{
+ float z,w,s,c,df;
+ uint32_t hx,ix;
+
+ GET_FLOAT_WORD(hx, x);
+ ix = hx & 0x7fffffff;
+ /* |x| >= 1 or nan */
+ if (ix >= 0x3f800000) {
+ if (ix == 0x3f800000) {
+ if (hx >> 31)
+ return 2*pio2_hi + 0x1p-120f;
+ return 0;
+ }
+ return 0/(x-x);
+ }
+ /* |x| < 0.5 */
+ if (ix < 0x3f000000) {
+ if (ix <= 0x32800000) /* |x| < 2**-26 */
+ return pio2_hi + 0x1p-120f;
+ return pio2_hi - (x - (pio2_lo-x*R(x*x)));
+ }
+ /* x < -0.5 */
+ if (hx >> 31) {
+ z = (1+x)*0.5f;
+ s = sqrtf(z);
+ w = R(z)*s-pio2_lo;
+ return 2*(pio2_hi - (s+w));
+ }
+ /* x > 0.5 */
+ z = (1-x)*0.5f;
+ s = sqrtf(z);
+ GET_FLOAT_WORD(hx,s);
+ SET_FLOAT_WORD(df,hx&0xfffff000);
+ c = (z-df*df)/(s+df);
+ w = R(z)*s+c;
+ return 2*(df+w);
+}