Split delinearize_index out of broadcast_util (#9056)

Left an #include behind for backward compatibility. Just needed so that broadcast_indexes_range.h can use delinearize_index

Author: swolchok

kernels/portable/cpu/util/broadcast_util.cpp

@@ -269,28 +269,6 @@ ET_NODISCARD Error get_broadcast_target_size(
       a.sizes(), b.sizes(), out_sizes, out_sizes_len, out_dim);
 }
 
-void delinearize_index(
-    size_t linear_index,
-    executorch::aten::ArrayRef<Tensor::SizesType> shape,
-    size_t* out_indexes,
-    const size_t out_indexes_len) {
-  ET_CHECK(shape.size() <= out_indexes_len);
-  for (size_t i = 0; i < shape.size(); ++i) {
-    auto dim = shape.size() - 1 - i;
-    auto dim_size = shape[dim];
-    out_indexes[dim] = linear_index % dim_size;
-    linear_index /= dim_size;
-  }
-}
-
-void delinearize_index(
-    size_t linear_index,
-    const Tensor& t,
-    size_t* out_indexes,
-    const size_t out_indexes_len) {
-  delinearize_index(linear_index, t.sizes(), out_indexes, out_indexes_len);
-}
-
 size_t linearize_access_indexes(
     ArrayRef<size_t> indexes_broadcast_to,
     ssize_t broadcast_to_ndim,

kernels/portable/cpu/util/broadcast_util.h

@@ -10,6 +10,7 @@
 
 #include <c10/util/irange.h>
 #include <executorch/kernels/portable/cpu/util/broadcast_indexes_range.h>
+#include <executorch/kernels/portable/cpu/util/delinearize_index.h>
 #include <executorch/runtime/core/exec_aten/exec_aten.h>
 #include <executorch/runtime/core/exec_aten/util/tensor_util.h>
 
@@ -207,36 +208,6 @@ ET_NODISCARD inline Error resize_to_broadcast_target_size(
 ET_DEPRECATED void free_broadcast_tensor(
     const executorch::aten::Tensor& broadcast_tensor);
 
-/**
- * Delinearize a flattened index to per-dimension indexes.
- *
- * @param[in] linear_index The flattened index
- * @param[in] shape The tensor shape
- * @param[out] out_indexes The per-dimension indexes
- * @param[in] out_indexes_len The maximum size of the out_indexes array
- * @returns void
- */
-void delinearize_index(
-    size_t linear_index,
-    executorch::aten::ArrayRef<Tensor::SizesType> shape,
-    size_t* out_indexes,
-    const size_t out_indexes_len);
-
-/**
- * Delinearize a flattened index to per-dimension indexes.
- *
- * @param[in] linear_index The flattened index
- * @param[in] t The tensor object
- * @param[out] out_indexes The per-dimension indexes
- * @param[in] out_indexes_len The maximum size of the out_indexes array
- * @returns void
- */
-void delinearize_index(
-    size_t linear_index,
-    const Tensor& t,
-    size_t* out_indexes,
-    const size_t out_indexes_len);
-
 /**
  * Return the linear index for broatcast_from tensor, given the indexes and
  * number of dimensions of broadcast_to tensor, and the shape and strides

kernels/portable/cpu/util/delinearize_index.cpp

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+#include <executorch/kernels/portable/cpu/util/delinearize_index.h>
+#include <executorch/runtime/core/exec_aten/exec_aten.h>
+
+namespace torch::executor {
+void delinearize_index(
+    size_t linear_index,
+    executorch::aten::ArrayRef<Tensor::SizesType> shape,
+    size_t* out_indexes,
+    const size_t out_indexes_len) {
+  ET_CHECK(shape.size() <= out_indexes_len);
+  for (size_t i = 0; i < shape.size(); ++i) {
+    auto dim = shape.size() - 1 - i;
+    auto dim_size = shape[dim];
+    out_indexes[dim] = linear_index % dim_size;
+    linear_index /= dim_size;
+  }
+}
+
+void delinearize_index(
+    size_t linear_index,
+    const Tensor& t,
+    size_t* out_indexes,
+    const size_t out_indexes_len) {
+  delinearize_index(linear_index, t.sizes(), out_indexes, out_indexes_len);
+}
+} // namespace torch::executor

kernels/portable/cpu/util/delinearize_index.h

@@ -0,0 +1,43 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <executorch/runtime/core/exec_aten/exec_aten.h>
+
+namespace torch::executor {
+/**
+ * Delinearize a flattened index to per-dimension indexes.
+ *
+ * @param[in] linear_index The flattened index
+ * @param[in] shape The tensor shape
+ * @param[out] out_indexes The per-dimension indexes
+ * @param[in] out_indexes_len The maximum size of the out_indexes array
+ * @returns void
+ */
+void delinearize_index(
+    size_t linear_index,
+    executorch::aten::ArrayRef<Tensor::SizesType> shape,
+    size_t* out_indexes,
+    const size_t out_indexes_len);
+
+/**
+ * Delinearize a flattened index to per-dimension indexes.
+ *
+ * @param[in] linear_index The flattened index
+ * @param[in] t The tensor object
+ * @param[out] out_indexes The per-dimension indexes
+ * @param[in] out_indexes_len The maximum size of the out_indexes array
+ * @returns void
+ */
+void delinearize_index(
+    size_t linear_index,
+    const Tensor& t,
+    size_t* out_indexes,
+    const size_t out_indexes_len);
+} // namespace torch::executor

kernels/portable/cpu/util/targets.bzl

@@ -66,9 +66,13 @@ def define_common_targets():
 
     runtime.cxx_library(
         name = "broadcast_util",
-        srcs = ["broadcast_util.cpp"],
+        srcs = [
+            "broadcast_util.cpp",
+            "delinearize_index.cpp",
+        ],
         exported_headers = [
             "broadcast_util.h",
+            "delinearize_index.h",
         ],
         exported_deps = [
             ":broadcast_indexes_range",