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authorIan Moffett <ian@osmora.org>2024-03-07 17:28:00 -0500
committerIan Moffett <ian@osmora.org>2024-03-07 17:28:32 -0500
commitbd5969fc876a10b18613302db7087ef3c40f18e1 (patch)
tree7c2b8619afe902abf99570df2873fbdf40a4d1a1 /lib/mlibc/options/ansi/musl-generic-math/cosf.c
parenta95b38b1b92b172e6cc4e8e56a88a30cc65907b0 (diff)
lib: Add mlibc
Signed-off-by: Ian Moffett <ian@osmora.org>
Diffstat (limited to 'lib/mlibc/options/ansi/musl-generic-math/cosf.c')
-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/cosf.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/cosf.c b/lib/mlibc/options/ansi/musl-generic-math/cosf.c
new file mode 100644
index 0000000..23f3e5b
--- /dev/null
+++ b/lib/mlibc/options/ansi/musl-generic-math/cosf.c
@@ -0,0 +1,78 @@
+/* origin: FreeBSD /usr/src/lib/msun/src/s_cosf.c */
+/*
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ * 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.
+ * ====================================================
+ */
+
+#include "libm.h"
+
+/* Small multiples of pi/2 rounded to double precision. */
+static const double
+c1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
+c2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
+c3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
+c4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
+
+float cosf(float x)
+{
+ double y;
+ uint32_t ix;
+ unsigned n, sign;
+
+ GET_FLOAT_WORD(ix, x);
+ sign = ix >> 31;
+ ix &= 0x7fffffff;
+
+ if (ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
+ if (ix < 0x39800000) { /* |x| < 2**-12 */
+ /* raise inexact if x != 0 */
+ FORCE_EVAL(x + 0x1p120f);
+ return 1.0f;
+ }
+ return __cosdf(x);
+ }
+ if (ix <= 0x407b53d1) { /* |x| ~<= 5*pi/4 */
+ if (ix > 0x4016cbe3) /* |x| ~> 3*pi/4 */
+ return -__cosdf(sign ? x+c2pio2 : x-c2pio2);
+ else {
+ if (sign)
+ return __sindf(x + c1pio2);
+ else
+ return __sindf(c1pio2 - x);
+ }
+ }
+ if (ix <= 0x40e231d5) { /* |x| ~<= 9*pi/4 */
+ if (ix > 0x40afeddf) /* |x| ~> 7*pi/4 */
+ return __cosdf(sign ? x+c4pio2 : x-c4pio2);
+ else {
+ if (sign)
+ return __sindf(-x - c3pio2);
+ else
+ return __sindf(x - c3pio2);
+ }
+ }
+
+ /* cos(Inf or NaN) is NaN */
+ if (ix >= 0x7f800000)
+ return x-x;
+
+ /* general argument reduction needed */
+ n = __rem_pio2f(x,&y);
+ switch (n&3) {
+ case 0: return __cosdf(y);
+ case 1: return __sindf(-y);
+ case 2: return -__cosdf(y);
+ default:
+ return __sindf(y);
+ }
+}