Fix StridedSlicePadIndices made output empty

PiperOrigin-RevId: 262864322

tensorflow/lite/kernels/internal/BUILD

@@ -785,6 +785,19 @@ cc_test(
     ],
 )
 
+cc_test(
+    name = "strided_slice_logic_test",
+    timeout = "moderate",
+    srcs = [
+        "strided_slice_logic_test.cc",
+    ],
+    shard_count = 4,
+    deps = [
+        ":strided_slice_logic",
+        "@com_google_googletest//:gtest_main",
+    ],
+)
+
 cc_test(
     name = "logsoftmax_quantized_test",
     timeout = "long",

tensorflow/lite/kernels/internal/strided_slice_logic.h

@@ -43,14 +43,14 @@ inline void StridedSlicePadIndices(tflite::StridedSliceParams* p,
   const int pad_count = dim_count - p->start_indices_count;
 
   // Pad indices at start, so move arrays by pad_count.
-  for (int i = p->start_indices_count - 1; i > 0; --i) {
+  for (int i = p->start_indices_count - 1; i >= 0; --i) {
     p->strides[i + pad_count] = p->strides[i];
     p->start_indices[i + pad_count] = p->start_indices[i];
     p->stop_indices[i + pad_count] = p->stop_indices[i];
   }
   for (int i = 0; i < pad_count; ++i) {
     p->start_indices[i] = 0;
-    p->stop_indices[i] = 0;
+    p->stop_indices[i] = 1;
     p->strides[i] = 1;
   }
 

tensorflow/lite/kernels/internal/strided_slice_logic_test.cc

@@ -0,0 +1,80 @@
+/* Copyright 2019 The TensorFlow Authors. All Rights Reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+==============================================================================*/
+#include "tensorflow/lite/kernels/internal/strided_slice_logic.h"
+
+#include <gtest/gtest.h>
+
+namespace tflite {
+namespace {
+
+void RunStridedSlicePadIndices(std::initializer_list<int> begin,
+                               std::initializer_list<int> end,
+                               std::initializer_list<int> stride,
+                               std::initializer_list<int> expected_begin,
+                               std::initializer_list<int> expected_end,
+                               std::initializer_list<int> expected_stride) {
+  StridedSliceParams op_params;
+  int dims = begin.size();
+  op_params.start_indices_count = dims;
+  op_params.stop_indices_count = dims;
+  op_params.strides_count = dims;
+
+  for (int i = 0; i < dims; ++i) {
+    op_params.start_indices[i] = begin.begin()[i];
+    op_params.stop_indices[i] = end.begin()[i];
+    op_params.strides[i] = stride.begin()[i];
+  }
+
+  strided_slice::StridedSlicePadIndices(&op_params, 4);
+
+  for (int i = 0; i < 4; ++i) {
+    EXPECT_EQ(op_params.start_indices[i], expected_begin.begin()[i]);
+    EXPECT_EQ(op_params.stop_indices[i], expected_end.begin()[i]);
+    EXPECT_EQ(op_params.strides[i], expected_stride.begin()[i]);
+  }
+}
+
+TEST(RunStridedSlicePadIndices, Pad1) {
+  RunStridedSlicePadIndices({1, 2, 3},     // begin
+                            {4, 5, 6},     // end
+                            {2, 2, 2},     // stride
+                            {0, 1, 2, 3},  // expected_begin
+                            {1, 4, 5, 6},  // expected_end
+                            {1, 2, 2, 2}   // expected_stride
+  );
+}
+
+TEST(RunStridedSlicePadIndices, Pad2) {
+  RunStridedSlicePadIndices({1, 2},        // begin
+                            {4, 5},        // end
+                            {2, 2},        // stride
+                            {0, 0, 1, 2},  // expected_begin
+                            {1, 1, 4, 5},  // expected_end
+                            {1, 1, 2, 2}   // expected_stride
+  );
+}
+
+TEST(RunStridedSlicePadIndices, Pad3) {
+  RunStridedSlicePadIndices({1},           // begin
+                            {4},           // end
+                            {2},           // stride
+                            {0, 0, 0, 1},  // expected_begin
+                            {1, 1, 1, 4},  // expected_end
+                            {1, 1, 1, 2}   // expected_stride
+  );
+}
+
+}  // namespace
+}  // namespace tflite