chromium / chromiumos / third_party / glibc-ports / refs/heads/factory-1987.B / . / sysdeps / alpha / fpu / s_trunc.c

/* Copyright (C) 2007 Free Software Foundation, Inc. | |

This file is part of the GNU C Library. | |

Contributed by Richard Henderson. | |

The GNU C Library is free software; you can redistribute it and/or | |

modify it under the terms of the GNU Lesser General Public | |

License as published by the Free Software Foundation; either | |

version 2.1 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 | |

Lesser General Public License for more details. | |

You should have received a copy of the GNU Lesser General Public | |

License along with the GNU C Library; if not, write to the Free | |

Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA | |

02111-1307 USA. */ | |

#include <math.h> | |

#include <math_ldbl_opt.h> | |

/* Use the chopped rounding mode conversion instructions to implement trunc. */ | |

double | |

__trunc (double x) | |

{ | |

double two52 = copysign (0x1.0p52, x); | |

double r, tmp; | |

__asm ( | |

#ifdef _IEEE_FP_INEXACT | |

"addt/suic %2, %3, %1\n\tsubt/suic %1, %3, %0" | |

#else | |

"addt/suc %2, %3, %1\n\tsubt/suc %1, %3, %0" | |

#endif | |

: "=&f"(r), "=&f"(tmp) | |

: "f"(x), "f"(two52)); | |

/* trunc(-0) == -0, and in general we'll always have the same | |

sign as our input. */ | |

return copysign (r, x); | |

} | |

weak_alias (__trunc, trunc) | |

#ifdef NO_LONG_DOUBLE | |

strong_alias (__trunc, __truncl) | |

weak_alias (__trunc, truncl) | |

#endif | |

#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_1) | |

compat_symbol (libm, __trunc, truncl, GLIBC_2_1); | |

#endif |