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-rw-r--r--sysdeps/powerpc/q_dtoq.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/sysdeps/powerpc/q_dtoq.c b/sysdeps/powerpc/q_dtoq.c
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+++ b/sysdeps/powerpc/q_dtoq.c
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+/* 64-bit floating point to 128-bit floating point.
+   Copyright (C) 1997 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 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 <quad_float.h>
+
+/* long double _q_dtoq(double a);
+   Convert 'a' to long double. Don't raise exceptions.
+   */
+
+void
+__q_dtoq(unsigned long long result[2], double a)
+{
+  unsigned ux, rx;
+  union {
+    double d;
+    unsigned long long u;
+  } u;
+
+  u.d = a;
+  result[1] = u.u << 64-4;
+  result[0] = u.u >> 4;
+  /* correct exponent bias */
+  rx = ((long long)u.u >> 52 & 0x87ff) + 16383-1023;
+
+  ux = u.u >> 52 & 0x7ff;
+  if (ux == 0)
+    {
+      if ((u.u & 0x7fffffffffffffffULL) == 0)
+	{
+	  /* +0.0 or -0.0.  */
+	  rx &= 0x8000;
+	}
+      else
+	{
+	  /* Denormalised number.  Renormalise.  */
+	  unsigned long long um = u.u & 0x000fffffffffffffULL;
+	  int cs = cntlzd(um) - 12 + 1;
+	  rx -= cs;
+	  um <<= cs;
+	  result[0] = um >> 4;
+	  result[1] = um << 64-4;
+	}
+    }
+  else if (ux == 0x7ff)
+    {
+      /* Inf or NaN.  */
+      rx |= 0x7fff;
+    }
+  *(unsigned short *)result = rx;
+}