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

/* Copyright (C) 1998, 1999, 2000, 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> | |

/* Use the -inf rounding mode conversion instructions to implement | |

floor. We note when the exponent is large enough that the value | |

must be integral, as this avoids unpleasant integer overflows. */ | |

float | |

__floorf (float x) | |

{ | |

if (isless (fabsf (x), 16777216.0f)) /* 1 << FLT_MANT_DIG */ | |

{ | |

/* Note that Alpha S_Floating is stored in registers in a | |

restricted T_Floating format, so we don't even need to | |

convert back to S_Floating in the end. The initial | |

conversion to T_Floating is needed to handle denormals. */ | |

float tmp1, tmp2, new_x; | |

__asm ("cvtst/s %3,%2\n\t" | |

#ifdef _IEEE_FP_INEXACT | |

"cvttq/svim %2,%1\n\t" | |

#else | |

"cvttq/svm %2,%1\n\t" | |

#endif | |

"cvtqt/m %1,%0\n\t" | |

: "=f"(new_x), "=&f"(tmp1), "=&f"(tmp2) | |

: "f"(x)); | |

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

sign as our input. */ | |

x = copysignf(new_x, x); | |

} | |

return x; | |

} | |

weak_alias (__floorf, floorf) |