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@@ -0,0 +1,63 @@
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+
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+ * ====================================================
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+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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+ *
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+ * Developed at SunPro, a Sun Microsystems, Inc. business.
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+ * Permission to use, copy, modify, and distribute this
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+ * software is freely granted, provided that this notice
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+ * is preserved.
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+ * ====================================================
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+ */
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+
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+
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+ * scalbn (double x, int n)
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+ * scalbn(x,n) returns x* 2**n computed by exponent
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+ * manipulation rather than by actually performing an
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+ * exponentiation or a multiplication.
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+ */
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+
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+#include "math.h"
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+#include "math_private.h"
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+
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+libm_hidden_proto(scalbln)
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+#ifdef __STDC__
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+static const double
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+#else
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+static double
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+#endif
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+two54 = 1.80143985094819840000e+16,
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+twom54 = 5.55111512312578270212e-17,
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+huge = 1.0e+300,
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+tiny = 1.0e-300;
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+
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+#ifdef __STDC__
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+ double scalbln (double x, long int n)
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+#else
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+ double scalbln (x,n)
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+ double x; long int n;
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+#endif
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+{
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+ int32_t k,hx,lx;
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+ EXTRACT_WORDS(hx,lx,x);
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+ k = (hx&0x7ff00000)>>20;
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+ if (k==0) {
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+ if ((lx|(hx&0x7fffffff))==0) return x;
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+ x *= two54;
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+ GET_HIGH_WORD(hx,x);
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+ k = ((hx&0x7ff00000)>>20) - 54;
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+ }
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+ if (k==0x7ff) return x+x;
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+ k = k+n;
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+ if (n> 50000 || k > 0x7fe)
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+ return huge*copysign(huge,x);
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+ if (n< -50000) return tiny*copysign(tiny,x);
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+ if (k > 0)
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+ {SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;}
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+ if (k <= -54)
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+ return tiny*copysign(tiny,x);
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+ k += 54;
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+ SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20));
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+ return x*twom54;
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+}
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+libm_hidden_def(scalbln)
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