/* Implementation of ishftc intrinsic. | |

Copyright (C) 2002-2021 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 |