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diff --git a/src/dsp/x86/common_avx2_test.cc b/src/dsp/x86/common_avx2_test.cc
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+++ b/src/dsp/x86/common_avx2_test.cc
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+// Copyright 2021 The libgav1 Authors
+//
+// 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 "src/dsp/x86/common_avx2.h"
+
+#include "gtest/gtest.h"
+
+#if LIBGAV1_TARGETING_AVX2
+
+#include <cstdint>
+
+#include "src/utils/common.h"
+
+namespace libgav1 {
+namespace dsp {
+namespace {
+
+// Show that RightShiftWithRounding_S16() is equal to
+// RightShiftWithRounding() only for values less than or equal to
+// INT16_MAX - ((1 << bits) >> 1). In particular, if bits == 16, then
+// RightShiftWithRounding_S16() is equal to RightShiftWithRounding() only for
+// negative values.
+TEST(CommonDspTest, AVX2RightShiftWithRoundingS16) {
+  for (int bits = 0; bits < 16; ++bits) {
+    const int bias = (1 << bits) >> 1;
+    for (int32_t value = INT16_MIN; value <= INT16_MAX; ++value) {
+      const __m256i v_val_d = _mm256_set1_epi16(value);
+      const __m256i v_result_d = RightShiftWithRounding_S16(v_val_d, bits);
+      // Note _mm256_extract_epi16 is avoided for compatibility with Visual
+      // Studio < 2017.
+      const int16_t result =
+          _mm_extract_epi16(_mm256_extracti128_si256(v_result_d, 0), 0);
+      const int32_t expected = RightShiftWithRounding(value, bits);
+      if (value <= INT16_MAX - bias) {
+        EXPECT_EQ(result, expected) << "value: " << value << ", bits: " << bits;
+      } else {
+        EXPECT_EQ(expected, 1 << (15 - bits));
+        EXPECT_EQ(result, -expected)
+            << "value: " << value << ", bits: " << bits;
+      }
+    }
+  }
+}
+
+}  // namespace
+}  // namespace dsp
+}  // namespace libgav1
+
+#else  // !LIBGAV1_TARGETING_AVX2
+
+TEST(CommonDspTest, AVX2) {
+  GTEST_SKIP() << "Build this module for x86(-64) with AVX2 enabled to enable "
+                  "the tests.";
+}
+
+#endif  // LIBGAV1_TARGETING_AVX2