From b1cd65d75ff061f9e4ad69ea174fe37e321073d2 Mon Sep 17 00:00:00 2001
From: Evgeny Kotov <evgeny.kotov@intel.com>
Date: Wed, 22 Feb 2023 12:23:14 +0100
Subject: [PATCH] refactor

---
 .../gather_sinking_transpose_reshape.cpp      | 53 +++++++++----------
 1 file changed, 25 insertions(+), 28 deletions(-)

diff --git a/src/plugins/intel_gna/src/transformations/gather_sinking_transpose_reshape.cpp b/src/plugins/intel_gna/src/transformations/gather_sinking_transpose_reshape.cpp
index b277f2f24b0f35..54680bbd68ce49 100644
--- a/src/plugins/intel_gna/src/transformations/gather_sinking_transpose_reshape.cpp
+++ b/src/plugins/intel_gna/src/transformations/gather_sinking_transpose_reshape.cpp
@@ -22,49 +22,46 @@ namespace {
 using NodePtr = std::shared_ptr<ov::Node>;
 using NodePair = std::pair<NodePtr, NodePtr>;
 
-std::vector<std::vector<size_t>> slice_by_increment_order(const Shape& transpose_order) {
-    if (transpose_order.empty())
-        return {};
-
-    std::vector<std::vector<size_t>> partition;
-    std::vector<size_t> sub_order;
-
-    for (size_t i = 0; i < transpose_order.size(); ++i) {
-        if (!i || transpose_order[i] == transpose_order[i - 1] + 1) {
-            sub_order.push_back(transpose_order[i]);
-            continue;
-        }
-        if (!sub_order.empty()) {
-            partition.push_back(sub_order);
-        }
-        sub_order.clear();
-        sub_order.push_back(transpose_order[i]);
-    }
-    if (!sub_order.empty()) {
-        partition.push_back(sub_order);
+size_t FindEndOfSlice(const Shape& transpose_order, size_t start_idx) {
+    size_t slice_end = start_idx;
+    for (size_t i = start_idx + 1; i < transpose_order.size(); ++i) {
+        if (transpose_order[i] != transpose_order[slice_end] + 1)
+            break;
+        slice_end = i;
     }
-
-    return partition;
+    return slice_end;
 }
 
 std::vector<int64_t> CreateGatherIndices(const Shape& transpose_input_shape,
                                                        const Shape& reshape_output_shape,
                                                        const Shape& transpose_order) {
-    const auto partition = slice_by_increment_order(transpose_order);
-    if (partition.size() != 3)
-        return {};
-    const int64_t transpose_part_0 = std::accumulate(partition[2].begin(), partition[2].end(), 1,
+
+    const size_t slice_0_end = FindEndOfSlice(transpose_order, 0);
+    const size_t slice_1_start = slice_0_end + 1;
+    const size_t slice_1_end = FindEndOfSlice(transpose_order, slice_1_start);
+    const size_t slice_2_start = slice_1_end + 1;
+
+    if (slice_0_end >= transpose_input_shape.size() ||
+        slice_1_start >= transpose_input_shape.size() ||
+        slice_1_end >= transpose_input_shape.size() ||
+        slice_2_start >= transpose_input_shape.size()) {
+            return {};
+        }
+
+    const int64_t transpose_part_0 = std::accumulate(transpose_order.begin() + slice_1_start,
+                                                     transpose_order.begin() + slice_1_end + 1, 1,
                                  [&transpose_input_shape](int64_t result, int64_t order_value) {
                                     return result *= transpose_input_shape[order_value];
                                  });
-    const int64_t transpose_part_1 = std::accumulate(partition[1].begin(), partition[1].end(), 1,
+    const int64_t transpose_part_1 = std::accumulate(transpose_order.begin() + slice_2_start,
+                                                     transpose_order.end(), 1,
                                  [&transpose_input_shape](int64_t result, int64_t order_value) {
                                     return result *= transpose_input_shape[order_value];
                                  });
 
     std::vector<int64_t> gather_indices_value(reshape_output_shape.back());
     for (size_t i = 0; i < gather_indices_value.size(); ++i) {
-        gather_indices_value[i] = transpose_part_1 * (i % transpose_part_0) + i / transpose_part_0;
+        gather_indices_value[i] = transpose_part_0 * (i % transpose_part_1) + i / transpose_part_1;
     }
 
     return gather_indices_value;