SparseHalo test failure with different halo parameters

[JStewart28]

I am using the SparseHalo object in Cabana. I have been exploring the sparse halo test (grid/unit_test/tstSparseHalo.hpp) to understand how it works.

I noticed that the test only tests a halo using a sparse local grid with four cells per tile. I tested the different parameter values and the test either failed or seg faulted:

constexpr int size_tile_per_dim = 32;
constexpr int cell_per_tile_dim = 8;
constexpr int cell_bits_per_tile_dim = decltype(sparse_map)::cell_bits_per_tile_dim;
int halo_width = 8;
int halo_tile_width = 1;

constexpr int size_tile_per_dim = 16;
constexpr int cell_per_tile_dim = 2;
constexpr int cell_bits_per_tile_dim = decltype(sparse_map)::cell_bits_per_tile_dim;
int halo_width = 4;
int halo_tile_width = 2;

Am I not understanding the sparse halo correctly, or is there a bug in the SparseHalo?

Update: If the cell_per_tile_dim is 4, the data value (EXPECT_DOUBLE_EQ) checks are failing. When cell_per_tile_dim is 2, a runtime error is thrown because tiles are not found.