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authorUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
committerUlrich Drepper <drepper@redhat.com>2004-12-22 20:10:10 +0000
commita334319f6530564d22e775935d9c91663623a1b4 (patch)
treeb5877475619e4c938e98757d518bb1e9cbead751 /sysdeps/m68k/fpu/e_pow.c
parent0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (diff)
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(CFLAGS-tst-align.c): Add -mpreferred-stack-boundary=4.
Diffstat (limited to 'sysdeps/m68k/fpu/e_pow.c')
-rw-r--r--sysdeps/m68k/fpu/e_pow.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/sysdeps/m68k/fpu/e_pow.c b/sysdeps/m68k/fpu/e_pow.c
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+++ b/sysdeps/m68k/fpu/e_pow.c
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+/* Copyright (C) 1997, 1999 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>
+#include "math_private.h"
+#include "mathimpl.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)
+#define m81(func) __m81_u(s(func))
+
+float_type
+s(__ieee754_pow) (float_type x, float_type y)
+{
+  float_type z;
+  float_type ax;
+  unsigned long x_cond, y_cond;
+
+  y_cond = __m81_test (y);
+  if (y_cond & __M81_COND_ZERO)
+    return 1.0;
+  if (y_cond & __M81_COND_NAN)
+    return x == 1.0 ? x : x + y;
+
+  x_cond = __m81_test (x);
+  if (x_cond & __M81_COND_NAN)
+    return x + y;
+
+  if (y_cond & __M81_COND_INF)
+    {
+      ax = s(fabs) (x);
+      if (ax == 1.0)
+	return ax;
+      if (ax > 1.0)
+	return y_cond & __M81_COND_NEG ? 0 : y;
+      else
+	return y_cond & __M81_COND_NEG ? -y : 0;
+    }
+
+  if (s(fabs) (y) == 1.0)
+    return y_cond & __M81_COND_NEG ? 1 / x : x;
+
+  if (y == 2)
+    return x * x;
+  if (y == 0.5 && !(x_cond & __M81_COND_NEG))
+    return m81(__ieee754_sqrt) (x);
+
+  if (x == 10.0)
+    {
+      __asm ("ftentox%.x %1, %0" : "=f" (z) : "f" (y));
+      return z;
+    }
+  if (x == 2.0)
+    {
+      __asm ("ftwotox%.x %1, %0" : "=f" (z) : "f" (y));
+      return z;
+    }
+
+  ax = s(fabs) (x);
+  if (x_cond & (__M81_COND_INF | __M81_COND_ZERO) || ax == 1.0)
+    {
+      z = ax;
+      if (y_cond & __M81_COND_NEG)
+	z = 1 / z;
+      if (x_cond & __M81_COND_NEG)
+	{
+	  if (y != m81(__rint) (y))
+	    {
+	      if (x == -1)
+		z = (z - z) / (z - z);
+	    }
+	  else
+	    goto maybe_negate;
+	}
+      return z;
+    }
+
+  if (x_cond & __M81_COND_NEG)
+    {
+      if (y == m81(__rint) (y))
+	{
+	  z = m81(__ieee754_exp) (y * m81(__ieee754_log) (-x));
+	maybe_negate:
+	  /* We always use the long double format, since y is already in
+	     this format and rounding won't change the result.  */
+	  {
+	    int32_t exponent;
+	    u_int32_t i0, i1;
+	    GET_LDOUBLE_WORDS (exponent, i0, i1, y);
+	    exponent = (exponent & 0x7fff) - 0x3fff;
+	    if (exponent <= 31
+		? i0 & (1 << (31 - exponent))
+		: (exponent <= 63
+		   && i1 & (1 << (63 - exponent))))
+	      z = -z;
+	  }
+	}
+      else
+	z = (y - y) / (y - y);
+    }
+  else
+    z = m81(__ieee754_exp) (y * m81(__ieee754_log) (x));
+  return z;
+}