| //===-- Support/MathExtras.h - Useful math functions ------------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by the LLVM research group and is distributed under |
| // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // 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 |
