/*
   * Copyright 2013 Tilera Corporation. All Rights Reserved.
   *
   *   This program is free software; you can redistribute it and/or
   *   modify it under the terms of the GNU General Public License
   *   as published by the Free Software Foundation, version 2.
   *
   *   This program 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, GOOD TITLE or
   *   NON INFRINGEMENT.  See the GNU General Public License for
   *   more details.
   *
   * Provide a mask based on the pointer alignment that
   * sets up non-zero bytes before the beginning of the string.
   * The MASK expression works because shift counts are taken mod 64.
   * Also, specify how to count "first" and "last" bits
   * when the bits have been read as a word.
   */
  
  #include <asm/byteorder.h>
  
  #ifdef __LITTLE_ENDIAN
  #define MASK(x) (__insn_shl(1ULL, (x << 3)) - 1)
  #define NULMASK(x) ((2ULL << x) - 1)
  #define CFZ(x) __insn_ctz(x)
  #define REVCZ(x) __insn_clz(x)
  #else
  #define MASK(x) (__insn_shl(-2LL, ((-x << 3) - 1)))
  #define NULMASK(x) (-2LL << (63 - x))
  #define CFZ(x) __insn_clz(x)
  #define REVCZ(x) __insn_ctz(x)
  #endif
  
  /*
   * Create eight copies of the byte in a uint64_t.  Byte Shuffle uses
   * the bytes of srcB as the index into the dest vector to select a
   * byte.  With all indices of zero, the first byte is copied into all
   * the other bytes.
   */
  static inline uint64_t copy_byte(uint8_t byte)
  {
  	return __insn_shufflebytes(byte, 0, 0);
  }