remquo implementation for double according to IEEE.

sysdeps/m68k/fpu/s_remquo.c

@@ -0,0 +1,58 @@
+/* Compute remainder and a congruent to the quotient.  m68k fpu version
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#define __LIBC_M81_MATH_INLINES
+#include <math.h>
+
+#ifndef SUFF
+#define SUFF
+#endif
+#ifndef float_type
+#define float_type double
+#endif
+
+#define CONCATX(a,b) __CONCAT(a,b)
+#define s(name) CONCATX(name,SUFF)
+
+float_type
+s(__remquo) (float_type x, float_type y, int *quo)
+{
+  float_type result;
+  int cquo, fpsr;
+
+  /* FIXME: Which of frem and fmod is correct?  */
+#if 1
+  __asm ("frem%.x %2,%0\n\tfmove%.l %/fpsr,%1"
+	 : "=f" (result), "=dm" (fpsr) : "f" (y), "0" (x));
+  cquo = (fpsr >> 16) & 0x7f;
+  if ((result > 0) != (x > 0))
+    cquo--;
+#else
+  __asm ("fmod%.x %2,%0\n\tfmove%.l %/fpsr,%1"
+	 : "=f" (result), "=dm" (fpsr) : "f" (y), "0" (x));
+  cquo = (fpsr >> 16) & 0x7f;
+#endif
+  if (fpsr & (1 << 23))
+    cquo = -cquo;
+  *quo = cquo;
+  return result;
+}
+#define weak_aliasx(a,b) weak_alias(a,b)
+weak_aliasx (s(__remquo), s(remquo))