include/polly/FlattenAlgo.h

   1 //===------ FlattenAlgo.h --------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // Main algorithm of the FlattenSchedulePass. This is a separate file to avoid
  11 // the unittest for this requiring linking against LLVM.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #ifndef POLLY_FLATTENALGO_H
  16 #define POLLY_FLATTENALGO_H
  17
  18 #include "polly/Support/GICHelper.h"
  19
  20 namespace polly {
  21 /// Recursively flatten a schedule.
  22 ///
  23 /// Reduce the number of scatter dimensions as much as possible without changing
  24 /// the relative order of instances in a schedule. Ideally, this results in a
  25 /// single scatter dimension, but it may not always be possible to combine
  26 /// dimensions, eg. if a dimension is unbounded. In worst case, the original
  27 /// schedule is returned.
  28 ///
  29 /// Schedules with fewer dimensions may be easier to understand for humans, but
  30 /// it should make no difference to the computer.
  31 ///
  32 /// @param Schedule The input schedule.
  33 ///
  34 /// @return The flattened schedule.
  35 isl::union_map flattenSchedule(isl::union_map Schedule);
  36 } // namespace polly
  37
  38 #endif /* POLLY_FLATTENALGO_H */