Add 'third_party/abseil_cpp/' from commit '768eb2ca2857342673fcd462792ce04b8bac3fa3' r/781

git-subtree-dir: third_party/abseil_cpp
git-subtree-mainline: ffb2ae54beb5796cd408fbe15d2d2da09ff37adf
git-subtree-split: 768eb2ca2857342673fcd462792ce04b8bac3fa3

1 files changed, 55 insertions, 0 deletions

diff --git a/third_party/abseil_cpp/absl/hash/internal/hash.cc b/third_party/abseil_cpp/absl/hash/internal/hash.cc
new file mode 100644
index 000000000000..b44ecb3a6b66
--- /dev/null
+++ b/third_party/abseil_cpp/absl/hash/internal/hash.cc
@@ -0,0 +1,55 @@
+// Copyright 2018 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.
+
+#include "absl/hash/internal/hash.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+namespace hash_internal {
+
+uint64_t CityHashState::CombineLargeContiguousImpl32(uint64_t state,
+                                                     const unsigned char* first,
+                                                     size_t len) {
+  while (len >= PiecewiseChunkSize()) {
+    state =
+        Mix(state, absl::hash_internal::CityHash32(reinterpret_cast<const char*>(first),
+                                         PiecewiseChunkSize()));
+    len -= PiecewiseChunkSize();
+    first += PiecewiseChunkSize();
+  }
+  // Handle the remainder.
+  return CombineContiguousImpl(state, first, len,
+                               std::integral_constant<int, 4>{});
+}
+
+uint64_t CityHashState::CombineLargeContiguousImpl64(uint64_t state,
+                                                     const unsigned char* first,
+                                                     size_t len) {
+  while (len >= PiecewiseChunkSize()) {
+    state =
+        Mix(state, absl::hash_internal::CityHash64(reinterpret_cast<const char*>(first),
+                                         PiecewiseChunkSize()));
+    len -= PiecewiseChunkSize();
+    first += PiecewiseChunkSize();
+  }
+  // Handle the remainder.
+  return CombineContiguousImpl(state, first, len,
+                               std::integral_constant<int, 8>{});
+}
+
+ABSL_CONST_INIT const void* const CityHashState::kSeed = &kSeed;
+
+}  // namespace hash_internal
+ABSL_NAMESPACE_END
+}  // namespace absl