[examples][MLIRSparseTensor] Add sparse tensor pack example

Signed-off-by: Avimitin <dev@avimit.in>

examples/MLIRSparseTensor/makefile

@@ -31,3 +31,16 @@ sparse-tensor-new-run:
 	TENSOR0=${SPARSE_MATRIX_A} TENSOR1=${SPARSE_MATRIX_B} \
 	${MLIR_CPU_RUNNER} -e main -O0 --entry-point-result=void \
 		--shared-libs=${MLIR_RUNNER_UTILS},${MLIR_C_RUNNER_UTILS}
+
+sparse-tensor-pack-lower:
+	@${MLIR_OPT} ./sparse-tensor-pack.mlir \
+		--sparse-compiler="enable-runtime-library=false" -o log.mlir
+sparse-tensor-pack-translate:
+	@${MLIR_OPT} ./sparse-tensor-pack.mlir \
+		--sparse-compiler="enable-runtime-library=false" | \
+	${MLIR_TRANSLATE} --mlir-to-llvmir -o log.ll
+sparse-tensor-pack-run:
+	@${MLIR_OPT} ./sparse-tensor-pack.mlir \
+		--sparse-compiler="enable-runtime-library=false" | \
+	${MLIR_CPU_RUNNER} -e main -O0 --entry-point-result=void \
+		--shared-libs=${MLIR_RUNNER_UTILS},${MLIR_C_RUNNER_UTILS}

examples/MLIRSparseTensor/sparse-tensor-pack.mlir

@@ -0,0 +1,56 @@
+#SortedCOO = #sparse_tensor.encoding<{
+  dimLevelType = [ "compressed-nu", "singleton" ]
+}>
+
+//func.func private @printMemrefF64()
+
+/// Operating on sparse matrix
+///
+/// [
+///  [0.0, 0.0, 1.1, 0.0],
+///  [2.2, 0.0, 0.0, 0.0],
+///  [0.0, 0.0, 0.0, 0.0],
+///  [0.0, 3.3, 0.0, 0.0],
+/// ]
+///
+func.func @main() {
+  // Pack the coordinate list into a sparse tensor
+  // <https://en.wikipedia.org/wiki/Sparse_matrix#Coordinate_list_(COO)>
+  %data = arith.constant dense<[1.1, 2.2, 3.3]> : tensor<3xf64>
+  %idxs = arith.constant dense<[[0,2], [1,0], [3,1]]> : tensor<3x2xindex>
+  %sm = sparse_tensor.pack %data, %idxs : tensor<3xf64>, tensor<3x2xindex> to tensor<4x4xf64, #SortedCOO>
+
+  // Iterate all the non-zero entry and print their coordinate and value
+  // Expect output:
+  // row col val
+  // 0   2   1   1   0   2  3   1   3
+  sparse_tensor.foreach in %sm : tensor<4x4xf64, #SortedCOO> do {
+    ^bb0(%row:index, %col: index, %val: f64) :
+      vector.print %row : index
+      vector.print %col : index
+      vector.print %val : f64
+  }
+
+  // Unpack the packed sparse tensor back to values, coordinate tensor, plus the amount of the non-zero.
+  %val, %coords, %count = sparse_tensor.unpack %sm : tensor<4x4xf64, #SortedCOO>
+      to tensor<3xf64>, tensor<3x2xindex>, i32
+
+  %c0 = arith.constant 0 : index
+  %f0 = arith.constant 0.0 : f64
+
+  // Print the value of the sparse tensor
+  // Expect ( 1.1, 2.2, 3.3 )
+  %vval = vector.transfer_read %val[%c0], %f0 : tensor<3xf64>, vector<3xf64>
+  vector.print %vval : vector<3xf64>
+
+  // print the coordinate of the non-zero
+  // Expect ( (0, 2), ( 1, 0 ), ( 3, 1 ) )
+  %vcoords = vector.transfer_read %coords[%c0, %c0], %c0 : tensor<3x2xindex>, vector<3x2xindex>
+  vector.print %vcoords : vector<3x2xindex>
+
+  // Print the amount of the sparse tensor
+  // Expect 3
+  vector.print %count : i32
+
+  return
+}