feat: add features to tflite::Span (#2664)
To tflite::Span, add constructors for arrays and std::arrays, equality
and inequality operators, and tests thereof.
BUG=see description
diff --git a/tensorflow/lite/micro/BUILD b/tensorflow/lite/micro/BUILD
index 97d6897..1753465 100644
--- a/tensorflow/lite/micro/BUILD
+++ b/tensorflow/lite/micro/BUILD
@@ -569,6 +569,18 @@
)
cc_test(
+ name = "span_test",
+ size = "small",
+ srcs = [
+ "span_test.cc",
+ ],
+ deps = [
+ ":span",
+ "//tensorflow/lite/micro/testing:micro_test",
+ ],
+)
+
+cc_test(
name = "testing_helpers_test",
srcs = [
"testing_helpers_test.cc",
diff --git a/tensorflow/lite/micro/span.h b/tensorflow/lite/micro/span.h
index eeb4c0b..9399f1d 100644
--- a/tensorflow/lite/micro/span.h
+++ b/tensorflow/lite/micro/span.h
@@ -16,6 +16,7 @@
#ifndef TENSORFLOW_LITE_MICRO_SPAN_H_
#define TENSORFLOW_LITE_MICRO_SPAN_H_
+#include <array>
#include <cstddef>
namespace tflite {
@@ -26,6 +27,13 @@
public:
constexpr Span(T* data, size_t size) noexcept : data_(data), size_(size) {}
+ template <size_t N>
+ constexpr Span(T (&data)[N]) noexcept : data_(data), size_(N) {}
+
+ template <size_t N>
+ constexpr Span(std::array<T, N>& array) noexcept
+ : data_(array.data()), size_(N) {}
+
constexpr T& operator[](size_t idx) const noexcept { return *(data_ + idx); }
constexpr T* data() const noexcept { return data_; }
@@ -36,6 +44,26 @@
size_t size_;
};
+template <typename A, typename B>
+bool operator==(const Span<A>& a, const Span<B>& b) {
+ if (a.size() != b.size()) {
+ return false;
+ }
+
+ for (size_t i = 0; i < a.size(); ++i) {
+ if (a[i] != b[i]) {
+ return false;
+ }
+ }
+
+ return true;
+}
+
+template <typename A, typename B>
+bool operator!=(const Span<A>& a, const Span<B>& b) {
+ return !(a == b);
+}
+
} // end namespace tflite
#endif // TENSORFLOW_LITE_MICRO_SPAN_H_
diff --git a/tensorflow/lite/micro/span_test.cc b/tensorflow/lite/micro/span_test.cc
new file mode 100644
index 0000000..ef906c6
--- /dev/null
+++ b/tensorflow/lite/micro/span_test.cc
@@ -0,0 +1,59 @@
+// Copyright 2024 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/micro/span.h"
+
+#include <array>
+
+#include "tensorflow/lite/micro/testing/micro_test.h"
+
+TF_LITE_MICRO_TESTS_BEGIN
+
+TF_LITE_MICRO_TEST(TestArrayInitialization) {
+ int a[]{1, 2, 3};
+ tflite::Span<int> s{a};
+ TF_LITE_MICRO_EXPECT(s.data() == a);
+ TF_LITE_MICRO_EXPECT(s.size() == sizeof(a) / sizeof(int));
+}
+
+TF_LITE_MICRO_TEST(TestStdArrayInitialization) {
+ std::array<char, 20> a;
+ tflite::Span<char> s{a};
+ TF_LITE_MICRO_EXPECT(s.data() == a.data());
+ TF_LITE_MICRO_EXPECT(s.size() == a.size());
+}
+
+TF_LITE_MICRO_TEST(TestEquality) {
+ constexpr int a[]{1, 2, 3};
+ constexpr int b[]{1, 2, 3};
+ constexpr int c[]{3, 2, 1};
+ tflite::Span<const int> s_a{a};
+ tflite::Span<const int> s_b{b};
+ tflite::Span<const int> s_c{c};
+ TF_LITE_MICRO_EXPECT_TRUE(s_a == s_b);
+ TF_LITE_MICRO_EXPECT_FALSE(s_a == s_c);
+}
+
+TF_LITE_MICRO_TEST(TestInequality) {
+ constexpr int a[]{1, 2, 3};
+ constexpr int b[]{1, 2, 3};
+ constexpr int c[]{3, 2, 1};
+ tflite::Span<const int> s_a{a};
+ tflite::Span<const int> s_b{b};
+ tflite::Span<const int> s_c{c};
+ TF_LITE_MICRO_EXPECT_FALSE(s_a != s_b);
+ TF_LITE_MICRO_EXPECT_TRUE(s_a != s_c);
+}
+
+TF_LITE_MICRO_TESTS_END
