feat: add gzip and new headers

1 files changed, 69 insertions, 0 deletions

diff --git a/lib/libm/cbrtf.c b/lib/libm/cbrtf.c
new file mode 100644
index 00000000..c394310d
--- /dev/null
+++ b/lib/libm/cbrtf.c
@@ -0,0 +1,69 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/s_cbrtf.c */
+/*
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ * Debugged and optimized by Bruce D. Evans.
+ */
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+/* cbrtf(x)
+ * Return cube root of x
+ */
+
+#include <math.h>
+#include <stdint.h>
+
+static const unsigned B1 = 709958130, /* B1 = (127-127.0/3-0.03306235651)*2**23
+				       */
+	B2 = 642849266; /* B2 = (127-127.0/3-24/3-0.03306235651)*2**23 */
+
+float cbrtf(float x)
+{
+	double_t r, T;
+	union {
+		float f;
+		uint32_t i;
+	} u = { x };
+	uint32_t hx = u.i & 0x7fffffff;
+
+	if (hx >= 0x7f800000) /* cbrt(NaN,INF) is itself */
+		return x + x;
+
+	/* rough cbrt to 5 bits */
+	if (hx < 0x00800000) { /* zero or subnormal? */
+		if (hx == 0)
+			return x; /* cbrt(+-0) is itself */
+		u.f = x * 0x1p24f;
+		hx = u.i & 0x7fffffff;
+		hx = hx / 3 + B2;
+	} else
+		hx = hx / 3 + B1;
+	u.i &= 0x80000000;
+	u.i |= hx;
+
+	/*
+	 * First step Newton iteration (solving t*t-x/t == 0) to 16 bits.  In
+	 * double precision so that its terms can be arranged for efficiency
+	 * without causing overflow or underflow.
+	 */
+	T = u.f;
+	r = T * T * T;
+	T = T * ((double_t)x + x + r) / (x + r + r);
+
+	/*
+	 * Second step Newton iteration to 47 bits.  In double precision for
+	 * efficiency and accuracy.
+	 */
+	r = T * T * T;
+	T = T * ((double_t)x + x + r) / (x + r + r);
+
+	/* rounding to 24 bits is perfect in round-to-nearest mode */
+	return T;
+}