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-rw-r--r--sysdeps/m68k/fpu/s_frexpl.c59
1 files changed, 59 insertions, 0 deletions
diff --git a/sysdeps/m68k/fpu/s_frexpl.c b/sysdeps/m68k/fpu/s_frexpl.c
new file mode 100644
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--- /dev/null
+++ b/sysdeps/m68k/fpu/s_frexpl.c
@@ -0,0 +1,59 @@
+/* Copyright (C) 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, write to the Free
+ Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ 02111-1307 USA. */
+
+#include <math.h>
+
+long double
+__frexpl (long double value, int *expptr)
+{
+ long double mantissa, exponent;
+ int iexponent;
+ unsigned long fpsr;
+
+ __asm ("ftst%.x %1\n"
+ "fmove%.l %/fpsr, %0"
+ : "=dm" (fpsr) : "f" (value));
+ if (fpsr & (7 << 24))
+ {
+ /* Not finite or zero. */
+ *expptr = 0;
+ return value;
+ }
+ __asm ("fgetexp%.x %1, %0" : "=f" (exponent) : "f" (value));
+ iexponent = (int) exponent + 1;
+ *expptr = iexponent;
+ /* Unnormalized numbers must be handled specially, otherwise fscale
+ results in overflow. */
+ if (iexponent <= -16384)
+ {
+ value *= 0x1p16383L;
+ iexponent += 16383;
+ }
+ else if (iexponent >= 16384)
+ {
+ value *= 0x1p-16383L;
+ iexponent -= 16383;
+ }
+
+ __asm ("fscale%.l %2, %0"
+ : "=f" (mantissa)
+ : "0" (value), "dmi" (-iexponent));
+ return mantissa;
+}
+
+weak_alias (__frexpl, frexpl)