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-rw-r--r--sysdeps/libm-ieee754/s_remquof.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_remquof.c b/sysdeps/libm-ieee754/s_remquof.c
new file mode 100644
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+++ b/sysdeps/libm-ieee754/s_remquof.c
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+/* Compute remainder and a congruent to the quotient.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   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.  */
+
+#include <math.h>
+
+#include "math_private.h"
+
+
+static const float zero = 0.0;
+
+
+float
+__remquof (float x, float y, int *quo)
+{
+  int32_t hx,hp;
+  u_int32_t sx;
+  int cquo;
+
+  GET_FLOAT_WORD (hx, x);
+  GET_FLOAT_WORD (hp, p);
+  sx = hx & 0x80000000;
+  qs = (sx ^ (hp & 0x80000000)) >> 31;
+  hp &= 0x7fffffff;
+  hx &= 0x7fffffff;
+
+  /* Purge off exception values.  */
+  if (hp == 0)
+    return (x * p) / (x * p); 			/* p = 0 */
+  if ((hx >= 0x7f800000)			/* x not finite */
+      || (hp > 0x7f800000))			/* p is NaN */
+    return (x * p) / (x * p);
+
+  if (hp <= 0x7dffffff)
+    {
+      x = __ieee754_fmodf (x, 8 * p);		/* now x < 8p */
+
+      if (fabs (x) >= 4 * fabs (p))
+	cquo += 4;
+    }
+
+  if ((hx - hp) == 0)
+    {
+      *quo = qs ? -1 : 1;
+      return zero * x;
+    }
+
+  x  = fabsf (x);
+  p  = fabsf (p);
+  cquo = 0;
+
+  if (x >= 2 * p)
+    {
+      x -= 4 * p;
+      cquo += 2;
+    }
+  if (x >= p)
+    {
+      x -= 2 * p;
+      ++cquo;
+    }
+
+  if (hp < 0x01000000)
+    {
+      if (x + x > p)
+	{
+	  x -= p;
+	  if (x + x >= p)
+	    x -= p;
+	}
+    }
+  else
+    {
+      float p_half = 0.5 * p;
+      if(x > p_half)
+	{
+	  x -= p;
+	  if (x >= p_half)
+	    x -= p;
+	}
+    }
+
+  *quo = qs ? -cquo : cquo;
+
+  GET_FLOAT_WORD (hx, x);
+  SET_FLOAT_WORD (x, hx ^ sx);
+  return x;
+}
+weak_alias (__remquof, remquof)