ceph/src/boost/libs/numeric/ublas/include/boost/numeric/ublas/detail/duff.hpp

   1 //
   2 //  Copyright (c) 2000-2002
   3 //  Joerg Walter, Mathias Koch
   4 //
   5 //  Distributed under the Boost Software License, Version 1.0. (See
   6 //  accompanying file LICENSE_1_0.txt or copy at
   7 //  http://www.boost.org/LICENSE_1_0.txt)
   8 //
   9 //  The authors gratefully acknowledge the support of
  10 //  GeNeSys mbH & Co. KG in producing this work.
  11 //
  12
  13 #ifndef _BOOST_UBLAS_DUFF_
  14 #define _BOOST_UBLAS_DUFF_
  15
  16 #define DD_SWITCH(n, d, r, expr) \
  17     { \
  18         unsigned r = ((n) + (d) - 1) / (d); \
  19         switch ((n) % (d))  { \
  20         case 0: do { expr;
  21 #define DD_CASE_I(i, expr) \
  22         case (i): expr;
  23 #define DD_WHILE(r) \
  24             } while (-- (r) > 0); \
  25         } \
  26     }
  27
  28 #define DD_1T(n, d, r, expr) \
  29     DD_WHILE(r)
  30 #define DD_2T(n, d, r, expr) \
  31     DD_CASE_I(1, expr) \
  32     DD_1T(n, d, r, expr)
  33 #define DD_3T(n, d, r, expr) \
  34     DD_CASE_I(2, expr) \
  35     DD_2T(n, d, r, expr)
  36 #define DD_4T(n, d, r, expr) \
  37     DD_CASE_I(3, expr) \
  38     DD_3T(n, d, r, expr)
  39 #define DD_5T(n, d, r, expr) \
  40     DD_CASE_I(4, expr) \
  41     DD_4T(n, d, r, expr)
  42 #define DD_6T(n, d, r, expr) \
  43     DD_CASE_I(5, expr) \
  44     DD_5T(n, d, r, expr)
  45 #define DD_7T(n, d, r, expr) \
  46     DD_CASE_I(6, expr) \
  47     DD_6T(n, d, r, expr)
  48 #define DD_8T(n, d, r, expr) \
  49     DD_CASE_I(7, expr) \
  50     DD_7T(n, d, r, expr)
  51
  52 #define DD(n, d, r, expr) \
  53     DD_SWITCH(n, d, r, expr) \
  54     DD_##d##T(n, d, r, expr)
  55
  56 #endif