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-rw-r--r--modules/fdlibm/src/s_tanf.cpp71
1 files changed, 71 insertions, 0 deletions
diff --git a/modules/fdlibm/src/s_tanf.cpp b/modules/fdlibm/src/s_tanf.cpp
new file mode 100644
index 0000000000..f72d28382b
--- /dev/null
+++ b/modules/fdlibm/src/s_tanf.cpp
@@ -0,0 +1,71 @@
+/* s_tanf.c -- float version of s_tan.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 <sys/cdefs.h>
+//__FBSDID("$FreeBSD$");
+
+#include <float.h>
+
+#define INLINE_KERNEL_TANDF
+#define INLINE_REM_PIO2F
+#include "math_private.h"
+#include "e_rem_pio2f.cpp"
+#include "k_tanf.cpp"
+
+/* Small multiples of pi/2 rounded to double precision. */
+static const double
+t1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
+t2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
+t3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
+t4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
+
+float
+tanf(float x)
+{
+ double y;
+ int32_t n, hx, ix;
+
+ GET_FLOAT_WORD(hx,x);
+ ix = hx & 0x7fffffff;
+
+ if(ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
+ if(ix<0x39800000) /* |x| < 2**-12 */
+ if(((int)x)==0) return x; /* x with inexact if x != 0 */
+ return __kernel_tandf(x,1);
+ }
+ if(ix<=0x407b53d1) { /* |x| ~<= 5*pi/4 */
+ if(ix<=0x4016cbe3) /* |x| ~<= 3pi/4 */
+ return __kernel_tandf(x + (hx>0 ? -t1pio2 : t1pio2), -1);
+ else
+ return __kernel_tandf(x + (hx>0 ? -t2pio2 : t2pio2), 1);
+ }
+ if(ix<=0x40e231d5) { /* |x| ~<= 9*pi/4 */
+ if(ix<=0x40afeddf) /* |x| ~<= 7*pi/4 */
+ return __kernel_tandf(x + (hx>0 ? -t3pio2 : t3pio2), -1);
+ else
+ return __kernel_tandf(x + (hx>0 ? -t4pio2 : t4pio2), 1);
+ }
+
+ /* tan(Inf or NaN) is NaN */
+ else if (ix>=0x7f800000) return x-x;
+
+ /* general argument reduction needed */
+ else {
+ n = __ieee754_rem_pio2f(x,&y);
+ /* integer parameter: 1 -- n even; -1 -- n odd */
+ return __kernel_tandf(y,1-((n&1)<<1));
+ }
+}