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#include "cutlass_unit_test.h"

#include <cutlass/trace.h>
#include <iostream>
#include <cute/layout.hpp>
#include <cute/layout_composed.hpp>  // cute::composition
#include <cute/swizzle.hpp>          // cute::Swizzle
#include <cute/swizzle_layout.hpp>   // cute::composition
#include <cute/tensor.hpp>

using namespace cute;

template <class Layout>
void
test_left_inverse(Layout const& layout)
{
  auto inv_layout = left_inverse(layout);

  CUTLASS_TRACE_HOST(layout << " ^ -1\n" << "  =>  \n" << inv_layout);

  for (int i = 0; i < size(layout); ++i) {
    //printf("%3d: %3d  %3d\n", i, int(layout(i)), int(inv_layout(layout(i))));
    EXPECT_EQ(inv_layout(layout(i)), i);
  }

  CUTLASS_TRACE_HOST("Composition: " << coalesce(composition(inv_layout, layout)));
}

TEST(CuTe_core, Inverse_left)
{
  {
  auto layout = Layout<Shape <_1>,
                       Stride<_0>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <Shape <_1,_1>>,
                       Stride<Stride<_0,_0>>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <_1>,
                       Stride<_1>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <_4>,
                       Stride<_1>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <_4>,
                       Stride<_2>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <_8, _4>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <_8, _4>,
                       Stride<_4, _1>>{};

  test_left_inverse(filter(layout));
  }

  {
  auto layout = Layout<Shape< _2,_4,_6>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <_2,_4,_6>,
                       Stride<_4,_1,_8>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = Layout<Shape <_4, _2>,
                       Stride<_1,_16>>{};

  test_left_inverse(layout);
  }

  //
  // Swizzle left_inverse
  //

  {
  auto layout = ComposedLayout<Swizzle<1,0,2>, _0, Layout<Shape <_4, _4>,
                                                          Stride<_1, _4>>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = ComposedLayout<Swizzle<1,0,2>, _0, Layout<Shape <_4, _4>,
                                                          Stride<_4, _1>>>{};

  test_left_inverse(layout);
  }

  {
  auto layout = ComposedLayout<Swizzle<1,0,1>, _0, Layout<Shape <_4, _4>,
                                                          Stride<_8, _1>>>{};

  test_left_inverse(layout);
  }

  //
  // Negative strides (beta support)
  // Post-conditions/layout indexing aren't generalized enough to support these yet
  // However, the composition post-condition is general enough.
  {
  auto layout = make_layout(Shape<_4>{}, Stride<Int<-1>>{});

  test_left_inverse(layout);
  }

  //{
  //auto layout = Layout<Shape < _2,_4>,
  //                     Stride<_m1,_2>>{};

  //test_left_inverse(layout);
  //}

  //{
  //auto layout = Layout<Shape < _2, _4>,
  //                     Stride< _4,_m1>>{};

  //test_left_inverse(layout);
  //}

  //{
  //auto layout = Layout<Shape < _2, _4, _6>,
  //                     Stride<_m1,_12,_m2>>{};

  //test_left_inverse(layout);
  //}
}