101 lines
3.2 KiB
C
101 lines
3.2 KiB
C
/* Implementation of ishftc intrinsic.
|
|
Copyright (C) 2002-2017 Free Software Foundation, Inc.
|
|
Contributed by Paul Brook <paul@nowt.org>
|
|
|
|
This file is part of the GNU Fortran 95 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"
|
|
|
|
extern GFC_INTEGER_4 ishftc4 (GFC_INTEGER_4, GFC_INTEGER_4, GFC_INTEGER_4);
|
|
export_proto(ishftc4);
|
|
|
|
GFC_INTEGER_4
|
|
ishftc4 (GFC_INTEGER_4 i, GFC_INTEGER_4 shift, GFC_INTEGER_4 size)
|
|
{
|
|
GFC_UINTEGER_4 mask, bits;
|
|
|
|
if (shift < 0)
|
|
shift = shift + size;
|
|
|
|
if (shift == 0 || shift == size)
|
|
return i;
|
|
|
|
/* In C, the result of the shift operator is undefined if the right operand
|
|
is greater than or equal to the number of bits in the left operand. So we
|
|
have to special case it for fortran. */
|
|
mask = ~((size == 32) ? (GFC_UINTEGER_4)0 : (~(GFC_UINTEGER_4)0 << size));
|
|
|
|
bits = i & mask;
|
|
|
|
return (i & ~mask) | ((bits << shift) & mask) | (bits >> (size - shift));
|
|
}
|
|
|
|
extern GFC_INTEGER_8 ishftc8 (GFC_INTEGER_8, GFC_INTEGER_4, GFC_INTEGER_4);
|
|
export_proto(ishftc8);
|
|
|
|
GFC_INTEGER_8
|
|
ishftc8 (GFC_INTEGER_8 i, GFC_INTEGER_4 shift, GFC_INTEGER_4 size)
|
|
{
|
|
GFC_UINTEGER_8 mask, bits;
|
|
|
|
if (shift < 0)
|
|
shift = shift + size;
|
|
|
|
if (shift == 0 || shift == size)
|
|
return i;
|
|
|
|
/* In C, the result of the shift operator is undefined if the right operand
|
|
is greater than or equal to the number of bits in the left operand. So we
|
|
have to special case it for fortran. */
|
|
mask = ~((size == 64) ? (GFC_UINTEGER_8)0 : (~(GFC_UINTEGER_8)0 << size));
|
|
|
|
bits = i & mask;
|
|
|
|
return (i & ~mask) | ((bits << shift) & mask) | (bits >> (size - shift));
|
|
}
|
|
|
|
#ifdef HAVE_GFC_INTEGER_16
|
|
extern GFC_INTEGER_16 ishftc16 (GFC_INTEGER_16, GFC_INTEGER_4, GFC_INTEGER_4);
|
|
export_proto(ishftc16);
|
|
|
|
GFC_INTEGER_16
|
|
ishftc16 (GFC_INTEGER_16 i, GFC_INTEGER_4 shift, GFC_INTEGER_4 size)
|
|
{
|
|
GFC_UINTEGER_16 mask, bits;
|
|
|
|
if (shift < 0)
|
|
shift = shift + size;
|
|
|
|
if (shift == 0 || shift == size)
|
|
return i;
|
|
|
|
/* In C, the result of the shift operator is undefined if the right operand
|
|
is greater than or equal to the number of bits in the left operand. So we
|
|
have to special case it for fortran. */
|
|
mask = ~((size == 128) ? (GFC_UINTEGER_16)0 : (~(GFC_UINTEGER_16)0 << size));
|
|
|
|
bits = i & mask;
|
|
|
|
return (i & ~mask) | ((bits << shift) & mask) | (bits >> (size - shift));
|
|
}
|
|
#endif
|