1 files changed, 52 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/dbl-64/s_logb.c b/REORG.TODO/sysdeps/ieee754/dbl-64/s_logb.c
new file mode 100644
index 0000000000..3a26b18f78
--- /dev/null
+++ b/REORG.TODO/sysdeps/ieee754/dbl-64/s_logb.c
@@ -0,0 +1,52 @@
+/* @(#)s_logb.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.
+ * ====================================================
+ */
+
+/*
+ * double logb(x)
+ * IEEE 754 logb. Included to pass IEEE test suite. Not recommend.
+ * Use ilogb instead.
+ */
+
+#include <math.h>
+#include <math_private.h>
+#include <fix-int-fp-convert-zero.h>
+
+double
+__logb (double x)
+{
+  int32_t lx, ix, rix;
+
+  EXTRACT_WORDS (ix, lx, x);
+  ix &= 0x7fffffff;             /* high |x| */
+  if ((ix | lx) == 0)
+    return -1.0 / fabs (x);
+  if (ix >= 0x7ff00000)
+    return x * x;
+  if (__glibc_unlikely ((rix = ix >> 20) == 0))
+    {
+      /* POSIX specifies that denormal number is treated as
+         though it were normalized.  */
+      int ma;
+      if (ix == 0)
+	ma = __builtin_clz (lx) + 32;
+      else
+	ma = __builtin_clz (ix);
+      rix -= ma - 12;
+    }
+  if (FIX_INT_FP_CONVERT_ZERO && rix == 1023)
+    return 0.0;
+  return (double) (rix - 1023);
+}
+weak_alias (__logb, logb)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__logb, __logbl) weak_alias (__logb, logbl)
+#endif