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-rw-r--r--sysdeps/powerpc/q_qtou.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/sysdeps/powerpc/q_qtou.c b/sysdeps/powerpc/q_qtou.c
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+/* 128-bit floating point to 32-bit fixed point unsigned integer.
+   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>
+
+/* unsigned int _q_qtou(const long double *a);
+   Convert 'a' to unsigned int by truncation.
+
+   Special cases:
+   -0: return 0
+   NaN: raise VXCVI, return 0
+   SNaN: raise VXSNAN, VXCVI, and return 0
+   Negative numbers (other than -0, but including -Inf): raise VXCVI, return 0
+   >= 2^32: raise VXCVI, return 0xffffffff
+   */
+
+unsigned int
+__q_qtou(const unsigned long long a[2])
+{
+  int ax;
+  unsigned result;
+  unsigned long long a0;
+
+  /* Deal with non-special cases.  */
+  a0 = a[0];
+  ax = (a0 >> 48) - 16383;
+  if (ax <= 31)
+    /* If we had a '>>' operator that behaved properly with respect to
+       large shifts, we wouldn't need the '& -(ax >> 31)' term, which
+       clears 'result' if ax is negative.  */
+    return (unsigned)(a0 >> 17  |  0x80000000) >> 31-ax  &  -(ax >> 31);
+
+  /* 'result' is 1 if a is negative, 0 otherwise.  */
+  result = a0 >> 63;
+  /* Check for -0, otherwise raise VXCVI.  */
+  if (a0 != 0x8000000000000000ULL  ||  a[1] != 0)
+  {
+    /* Check for SNaN, if so raise VXSNAN.  */
+    if ((a0 >> 32  &  0x7fff8000) == 0x7fff0000
+	&& (a[1]  |  a0 & 0x00007fffffffffffULL) != 0)
+      set_fpscr_bit(FPSCR_VXSNAN);
+    /* Treat all NaNs as large negative numbers.  */
+    result |= cntlzw(~(a0 >> 32)  &  0x7fff0000) >> 5;
+
+    set_fpscr_bit(FPSCR_VXCVI);
+  }
+  return result-1;
+}