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Diffstat (limited to 'ports/sysdeps/m68k/m680x0/fpu/s_logbl.c')
-rw-r--r--ports/sysdeps/m68k/m680x0/fpu/s_logbl.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/ports/sysdeps/m68k/m680x0/fpu/s_logbl.c b/ports/sysdeps/m68k/m680x0/fpu/s_logbl.c
new file mode 100644
index 0000000000..2586622bf7
--- /dev/null
+++ b/ports/sysdeps/m68k/m680x0/fpu/s_logbl.c
@@ -0,0 +1,49 @@
+/* s_logbl.c -- long double version of s_logb.c.
+ * Conversion to long double by Ulrich Drepper,
+ * Cygnus Support, drepper@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.
+ * ====================================================
+ */
+
+/*
+ * long double logbl(x)
+ * IEEE 754 logb. Included to pass IEEE test suite. Not recommend.
+ * Use ilogb instead.
+ */
+
+#include <math.h>
+#include <math_private.h>
+
+long double
+__logbl (long double x)
+{
+ int32_t es, lx, ix;
+
+ GET_LDOUBLE_WORDS (es, ix, lx, x);
+ es &= 0x7fff; /* exponent */
+ if ((es | ix | lx) == 0)
+ return -1.0 / fabsl (x);
+ if (es == 0x7fff)
+ return x * x;
+ if (es == 0) /* IEEE 754 logb */
+ {
+ /* POSIX specifies that denormal number is treated as
+ though it were normalized. */
+ if (ix == 0)
+ es = -(__builtin_clz (lx) + 32);
+ else
+ es = -__builtin_clz (ix);
+ }
+ return (long double) (es - 16383);
+}
+
+weak_alias (__logbl, logbl)