Retro68/gcc/libgfortran/intrinsics/bit_intrinsics.c
2014-09-21 19:33:12 +02:00

139 lines
2.4 KiB
C

/* Implementation of the bit intrinsics not implemented as GCC builtins.
Copyright (C) 2009-2014 Free Software Foundation, Inc.
This file is part of the GNU Fortran runtime library (libgfortran).
Libgfortran is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public
License as published by the Free Software Foundation; either
version 3 of the License, or (at your option) any later version.
Libgfortran 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 General Public License for more details.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
#include "libgfortran.h"
#ifdef HAVE_GFC_INTEGER_16
extern int clz128 (GFC_INTEGER_16);
export_proto(clz128);
int
clz128 (GFC_INTEGER_16 x)
{
int res = 127;
// We can't write 0xFFFFFFFFFFFFFFFF0000000000000000, so we work around it
if (x & ((__uint128_t) 0xFFFFFFFFFFFFFFFF << 64))
{
res -= 64;
x >>= 64;
}
if (x & 0xFFFFFFFF00000000)
{
res -= 32;
x >>= 32;
}
if (x & 0xFFFF0000)
{
res -= 16;
x >>= 16;
}
if (x & 0xFF00)
{
res -= 8;
x >>= 8;
}
if (x & 0xF0)
{
res -= 4;
x >>= 4;
}
if (x & 0xC)
{
res -= 2;
x >>= 2;
}
if (x & 0x2)
{
res -= 1;
x >>= 1;
}
return res;
}
#endif
#ifdef HAVE_GFC_INTEGER_16
extern int ctz128 (GFC_INTEGER_16);
export_proto(ctz128);
int
ctz128 (GFC_INTEGER_16 x)
{
int res = 0;
if ((x & 0xFFFFFFFFFFFFFFFF) == 0)
{
res += 64;
x >>= 64;
}
if ((x & 0xFFFFFFFF) == 0)
{
res += 32;
x >>= 32;
}
if ((x & 0xFFFF) == 0)
{
res += 16;
x >>= 16;
}
if ((x & 0xFF) == 0)
{
res += 8;
x >>= 8;
}
if ((x & 0xF) == 0)
{
res += 4;
x >>= 4;
}
if ((x & 0x3) == 0)
{
res += 2;
x >>= 2;
}
if ((x & 0x1) == 0)
{
res += 1;
x >>= 1;
}
return res;
}
#endif