1 files changed, 63 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/dbl-64/e_ilogb.c b/REORG.TODO/sysdeps/ieee754/dbl-64/e_ilogb.c
new file mode 100644
index 0000000000..1e338a59c1
--- /dev/null
+++ b/REORG.TODO/sysdeps/ieee754/dbl-64/e_ilogb.c
@@ -0,0 +1,63 @@
+/* @(#)s_ilogb.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * 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_ilogb.c,v 1.9 1995/05/10 20:47:28 jtc Exp $";
+#endif
+
+/* ilogb(double x)
+ * return the binary exponent of non-zero x
+ * ilogb(0) = FP_ILOGB0
+ * ilogb(NaN) = FP_ILOGBNAN (no signal is raised)
+ * ilogb(+-Inf) = INT_MAX (no signal is raised)
+ */
+
+#include <limits.h>
+#include <math.h>
+#include <math_private.h>
+
+int
+__ieee754_ilogb (double x)
+{
+  int32_t hx, lx, ix;
+
+  GET_HIGH_WORD (hx, x);
+  hx &= 0x7fffffff;
+  if (hx < 0x00100000)
+    {
+      GET_LOW_WORD (lx, x);
+      if ((hx | lx) == 0)
+	return FP_ILOGB0;               /* ilogb(0) = FP_ILOGB0 */
+      else                              /* subnormal x */
+      if (hx == 0)
+	{
+	  for (ix = -1043; lx > 0; lx <<= 1)
+	    ix -= 1;
+	}
+      else
+	{
+	  for (ix = -1022, hx <<= 11; hx > 0; hx <<= 1)
+	    ix -= 1;
+	}
+      return ix;
+    }
+  else if (hx < 0x7ff00000)
+    return (hx >> 20) - 1023;
+  else if (FP_ILOGBNAN != INT_MAX)
+    {
+      /* ISO C99 requires ilogb(+-Inf) == INT_MAX.  */
+      GET_LOW_WORD (lx, x);
+      if (((hx ^ 0x7ff00000) | lx) == 0)
+	return INT_MAX;
+    }
+  return FP_ILOGBNAN;
+}