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 | //===-- Support/MathExtras.h - Useful math functions ------------*- C++ -*-===//
//
// This file contains some functions that are useful for math stuff.
//
//===----------------------------------------------------------------------===//
#ifndef SUPPORT_MATHEXTRAS_H
#define SUPPORT_MATHEXTRAS_H
#include "Support/DataTypes.h"
inline unsigned log2(uint64_t C) {
  unsigned getPow;
  for (getPow = 0; C > 1; ++getPow)
    C >>= 1;
  return getPow;
}
inline bool isPowerOf2(int64_t C, unsigned &getPow) {
  if (C < 0) C = -C;
  if (C > 0 && C == (C & ~(C - 1))) {
    getPow = log2((uint64_t)C);
    return true;
  }
  return false;
}
#endif
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