| /* Implementation of ishftc intrinsic. |
| Copyright 2002, 2004 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 2 of the License, or (at your option) any later version. |
| |
| In addition to the permissions in the GNU General Public License, the |
| Free Software Foundation gives you unlimited permission to link the |
| compiled version of this file into combinations with other programs, |
| and to distribute those combinations without any restriction coming |
| from the use of this file. (The General Public License restrictions |
| do apply in other respects; for example, they cover modification of |
| the file, and distribution when not linked into a combine |
| executable.) |
| |
| 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. |
| |
| You should have received a copy of the GNU General Public |
| License along with libgfortran; see the file COPYING. If not, |
| write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| Boston, MA 02110-1301, USA. */ |
| |
| #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) ? 0 : (~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) ? 0 : (~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) ? 0 : (~0 << size)); |
| |
| bits = i & mask; |
| |
| return (i & ~mask) | ((bits << shift) & mask) | (bits >> (size - shift)); |
| } |
| #endif |