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diff --git a/absl/crc/internal/crc32c_inline.h b/absl/crc/internal/crc32c_inline.h
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+// Copyright 2022 The Abseil 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
+//
+// https://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.
+
+#ifndef ABSL_CRC_INTERNAL_CRC32C_INLINE_H_
+#define ABSL_CRC_INTERNAL_CRC32C_INLINE_H_
+
+#include <cstdint>
+
+#include "absl/base/config.h"
+#include "absl/base/internal/endian.h"
+#include "absl/crc/internal/crc32_x86_arm_combined_simd.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace crc_internal {
+
+// CRC32C implementation optimized for small inputs.
+// Either computes crc and return true, or if there is
+// no hardware support does nothing and returns false.
+inline bool ExtendCrc32cInline(uint32_t* crc, const char* p, size_t n) {
+#if defined(ABSL_CRC_INTERNAL_HAVE_ARM_SIMD) || \
+ defined(ABSL_CRC_INTERNAL_HAVE_X86_SIMD)
+ constexpr uint32_t kCrc32Xor = 0xffffffffU;
+ *crc ^= kCrc32Xor;
+ if (n & 1) {
+ *crc = CRC32_u8(*crc, *p);
+ n--;
+ p++;
+ }
+ if (n & 2) {
+ *crc = CRC32_u16(*crc, absl::little_endian::Load16(p));
+ n -= 2;
+ p += 2;
+ }
+ if (n & 4) {
+ *crc = CRC32_u32(*crc, absl::little_endian::Load32(p));
+ n -= 4;
+ p += 4;
+ }
+ while (n) {
+ *crc = CRC32_u64(*crc, absl::little_endian::Load64(p));
+ n -= 8;
+ p += 8;
+ }
+ *crc ^= kCrc32Xor;
+ return true;
+#else
+ // No hardware support, signal the need to fallback.
+ static_cast<void>(crc);
+ static_cast<void>(p);
+ static_cast<void>(n);
+ return false;
+#endif // defined(ABSL_CRC_INTERNAL_HAVE_ARM_SIMD) ||
+ // defined(ABSL_CRC_INTERNAL_HAVE_X86_SIMD)
+}
+
+} // namespace crc_internal
+ABSL_NAMESPACE_END
+} // namespace absl
+
+#endif // ABSL_CRC_INTERNAL_CRC32C_INLINE_H_