Reshape method #1760
Reshape method #1760
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artv3
requested review from
MrBurmark,
adayton1,
rhornung67,
mdavis36,
johnbowen42,
rchen20 and
long58
| * to correspond to the matrix entry in the row, r, | ||
| * column, c, of matrix, e. Below we describe the two |
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I'm not sure what the right way to put commas here is, it feels a bit awkward to have so many commas so close together.
| // make_permuted_layout takes the number of entries in each dimension and a | ||
| // templated array indicating index arguments with slowest to fastest stride. |
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Should this just be an array? Do you mean to say that any array-like class can be used or that it has to be a std::array but the types stored in the array can vary but have to be convertible to integers, or something else?
| // RAJA::Layout objects may be templated on dimension, argument type, and | ||
| // index with unit stride. Here, the column index has unit stride (argument 2). |
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Can you supply the permutation at compile time, via camp::list or std::index_sequence, and have it produce a view with the right unit stride index?
| // | ||
| // _permutedlayout_permviews_start | ||
| #if 0 | ||
| std::array<RAJA::idx_t, 3> perm2 {{0, 1, 2}}; |
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Isn't perm 2 the same as perm 1?
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hey.. .thats right. Sorry this was just a scratch pad to prototype the reshape methods. I can give a 2 mins overview at the meeting on the general direction I was going.
| Cview(e, 0, 0) = Aview(e, 0, 0) * Bview(e, 0, 0) | ||
| + Aview(e, 0, 1) * Bview(e, 1, 0) | ||
| + Aview(e, 0, 2) * Bview(e, 2, 0); |
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This spacing does not spark joy.
| { | ||
| constexpr int N = sizeof...(Ts); |
| ///Should be a away to do this at compile time... | ||
| std::array<RAJA::idx_t, N> reverse_indices_array; | ||
| for(int i = N-1, j=0; i>-1; --i, j++) {reverse_indices_array[j] = i; } |
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Make an array of {s...} and an integer_sequence of 0...(N-1), pass them into a function, and then you'll have all the information you need to do the re-indexing.
| static auto get(T *ptr, Ts... s) | ||
| { | ||
| constexpr int N = sizeof...(Ts); | ||
| return RAJA::View<T, RAJA::Layout<N, RAJA::Index_type, N-1>>(ptr, s...); |
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Can you add an alias for the view_type?
| struct layout_left{}; | ||
| struct layout_right{}; | ||
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| template<typename LAYOUT> |
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Can we add a specialization for a generic index sequence like std::index_sequence?
Summary
This PR adds helper methods to views to create Reshape methods with compile time options C and Fortran style indexing