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-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/cbrtf.c66
1 files changed, 0 insertions, 66 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/cbrtf.c b/lib/mlibc/options/ansi/musl-generic-math/cbrtf.c
deleted file mode 100644
index 89c2c86..0000000
--- a/lib/mlibc/options/ansi/musl-generic-math/cbrtf.c
+++ /dev/null
@@ -1,66 +0,0 @@
-/* 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;
-}