[Mlir-commits] [mlir] [mlir][sparse] introduce `sparse_tensor.extract_iteration_space` operation. (PR #88554)

[Aart Bik]

================
@@ -1430,6 +1430,57 @@ def SparseTensor_ForeachOp : SparseTensor_Op<"foreach",
   let hasVerifier = 1;
 }
 
+//===----------------------------------------------------------------------===//
+// Sparse Tensor Iteration Operations.
+//===----------------------------------------------------------------------===//
+
+def ExtractIterSpaceOp : SparseTensor_Op<"extract_iteration_space",
+    [Pure, DeclareOpInterfaceMethods<InferTypeOpInterface>]> {
+
+  let arguments = (ins AnySparseTensor:$tensor,
+                       Optional<AnySparseIterator>:$parentIter,
+                       LevelAttr:$loLvl, LevelAttr:$hiLvl);
+
+  let results = (outs AnySparseIterSpace:$resultSpace);
+
+  let summary = "Extract an iteration space from a sparse tensor between certain levels";
+  let description = [{
+      Extracts a `!sparse_tensor.iter_space` from a sparse tensor between
+      certian (consecutive) levels.
+
+      `tensor`: the input sparse tensor that defines the iteration space.
+      `parentIter`: the iterator for the previous level, at which the iteration space
+      at the current levels will be extracted.
+      `loLvl`, `hiLvl`: the level range between [loLvl, hiLvl) in the input tensor that
+      the returned iteration space covers. `hiLvl - loLvl` defines the dimension of the
+      iteration space.
+
+      Example:
+      ```mlir
+      // Extracts a 1-D iteration space from a COO tensor at level 1.
+      %space = sparse_tensor.iteration.extract_space %sp at %it1 lvls = 1
----------------
aartbik wrote:

for now, since you only introduce one op, this can be as is, but we need to expand this example later with operations on the %space object

https://github.com/llvm/llvm-project/pull/88554