nest-open-source / nest-learning-thermostat / 5.1.7 / nspr / refs/heads/master / . / nspr-4.8.6 / mozilla / nsprpub / pr / src / misc / prlog2.c

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#include "prbit.h" | |

/* | |

** Compute the log of the least power of 2 greater than or equal to n | |

*/ | |

PR_IMPLEMENT(PRIntn) PR_CeilingLog2(PRUint32 n) | |

{ | |

PRIntn log2; | |

PR_CEILING_LOG2(log2, n); | |

return log2; | |

} | |

/* | |

** Compute the log of the greatest power of 2 less than or equal to n. | |

** This really just finds the highest set bit in the word. | |

*/ | |

PR_IMPLEMENT(PRIntn) PR_FloorLog2(PRUint32 n) | |

{ | |

PRIntn log2; | |

PR_FLOOR_LOG2(log2, n); | |

return log2; | |

} |