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Diffstat (limited to 'sysdeps/ieee754/flt-32/s_scalbnf.c')
-rw-r--r--sysdeps/ieee754/flt-32/s_scalbnf.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/sysdeps/ieee754/flt-32/s_scalbnf.c b/sysdeps/ieee754/flt-32/s_scalbnf.c
new file mode 100644
index 0000000000..11b77bd6c2
--- /dev/null
+++ b/sysdeps/ieee754/flt-32/s_scalbnf.c
@@ -0,0 +1,63 @@
+/* s_scalbnf.c -- float version of s_scalbn.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: s_scalbnf.c,v 1.4 1995/05/10 20:48:10 jtc Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const float
+#else
+static float
+#endif
+two25 = 3.355443200e+07, /* 0x4c000000 */
+twom25 = 2.9802322388e-08, /* 0x33000000 */
+huge = 1.0e+30,
+tiny = 1.0e-30;
+
+#ifdef __STDC__
+ float __scalbnf (float x, int n)
+#else
+ float __scalbnf (x,n)
+ float x; int n;
+#endif
+{
+ int32_t k,ix;
+ GET_FLOAT_WORD(ix,x);
+ k = (ix&0x7f800000)>>23; /* extract exponent */
+ if (k==0) { /* 0 or subnormal x */
+ if ((ix&0x7fffffff)==0) return x; /* +-0 */
+ x *= two25;
+ GET_FLOAT_WORD(ix,x);
+ k = ((ix&0x7f800000)>>23) - 25;
+ }
+ if (k==0xff) return x+x; /* NaN or Inf */
+ k = k+n;
+ if (n> 50000 || k > 0xfe)
+ return huge*copysignf(huge,x); /* overflow */
+ if (n< -50000)
+ return tiny*copysignf(tiny,x); /*underflow*/
+ if (k > 0) /* normal result */
+ {SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23)); return x;}
+ if (k <= -25)
+ return tiny*copysignf(tiny,x); /*underflow*/
+ k += 25; /* subnormal result */
+ SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23));
+ return x*twom25;
+}
+weak_alias (__scalbnf, scalbnf)