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authorvitalyisaev <vitalyisaev@yandex-team.com>2023-06-29 10:00:50 +0300
committervitalyisaev <vitalyisaev@yandex-team.com>2023-06-29 10:00:50 +0300
commit6ffe9e53658409f212834330e13564e4952558f6 (patch)
tree85b1e00183517648b228aafa7c8fb07f5276f419 /contrib/libs/llvm14/include/llvm/ADT/CachedHashString.h
parent726057070f9c5a91fc10fde0d5024913d10f1ab9 (diff)
downloadydb-6ffe9e53658409f212834330e13564e4952558f6.tar.gz
YQ Connector: support managed ClickHouse
Со стороны dqrun можно обратиться к инстансу коннектора, который работает на streaming стенде, и извлечь данные из облачного CH.
Diffstat (limited to 'contrib/libs/llvm14/include/llvm/ADT/CachedHashString.h')
-rw-r--r--contrib/libs/llvm14/include/llvm/ADT/CachedHashString.h195
1 files changed, 195 insertions, 0 deletions
diff --git a/contrib/libs/llvm14/include/llvm/ADT/CachedHashString.h b/contrib/libs/llvm14/include/llvm/ADT/CachedHashString.h
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+++ b/contrib/libs/llvm14/include/llvm/ADT/CachedHashString.h
@@ -0,0 +1,195 @@
+#pragma once
+
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+#endif
+
+//===- llvm/ADT/CachedHashString.h - Prehashed string/StringRef -*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file defines CachedHashString and CachedHashStringRef. These are
+/// owning and not-owning string types that store their hash in addition to
+/// their string data.
+///
+/// Unlike std::string, CachedHashString can be used in DenseSet/DenseMap
+/// (because, unlike std::string, CachedHashString lets us have empty and
+/// tombstone values).
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ADT_CACHEDHASHSTRING_H
+#define LLVM_ADT_CACHEDHASHSTRING_H
+
+#include "llvm/ADT/DenseMapInfo.h"
+#include "llvm/ADT/StringRef.h"
+
+namespace llvm {
+
+/// A container which contains a StringRef plus a precomputed hash.
+class CachedHashStringRef {
+ const char *P;
+ uint32_t Size;
+ uint32_t Hash;
+
+public:
+ // Explicit because hashing a string isn't free.
+ explicit CachedHashStringRef(StringRef S)
+ : CachedHashStringRef(S, DenseMapInfo<StringRef>::getHashValue(S)) {}
+
+ CachedHashStringRef(StringRef S, uint32_t Hash)
+ : P(S.data()), Size(S.size()), Hash(Hash) {
+ assert(S.size() <= std::numeric_limits<uint32_t>::max());
+ }
+
+ StringRef val() const { return StringRef(P, Size); }
+ const char *data() const { return P; }
+ uint32_t size() const { return Size; }
+ uint32_t hash() const { return Hash; }
+};
+
+template <> struct DenseMapInfo<CachedHashStringRef> {
+ static CachedHashStringRef getEmptyKey() {
+ return CachedHashStringRef(DenseMapInfo<StringRef>::getEmptyKey(), 0);
+ }
+ static CachedHashStringRef getTombstoneKey() {
+ return CachedHashStringRef(DenseMapInfo<StringRef>::getTombstoneKey(), 1);
+ }
+ static unsigned getHashValue(const CachedHashStringRef &S) {
+ assert(!isEqual(S, getEmptyKey()) && "Cannot hash the empty key!");
+ assert(!isEqual(S, getTombstoneKey()) && "Cannot hash the tombstone key!");
+ return S.hash();
+ }
+ static bool isEqual(const CachedHashStringRef &LHS,
+ const CachedHashStringRef &RHS) {
+ return LHS.hash() == RHS.hash() &&
+ DenseMapInfo<StringRef>::isEqual(LHS.val(), RHS.val());
+ }
+};
+
+/// A container which contains a string, which it owns, plus a precomputed hash.
+///
+/// We do not null-terminate the string.
+class CachedHashString {
+ friend struct DenseMapInfo<CachedHashString>;
+
+ char *P;
+ uint32_t Size;
+ uint32_t Hash;
+
+ static char *getEmptyKeyPtr() { return DenseMapInfo<char *>::getEmptyKey(); }
+ static char *getTombstoneKeyPtr() {
+ return DenseMapInfo<char *>::getTombstoneKey();
+ }
+
+ bool isEmptyOrTombstone() const {
+ return P == getEmptyKeyPtr() || P == getTombstoneKeyPtr();
+ }
+
+ struct ConstructEmptyOrTombstoneTy {};
+
+ CachedHashString(ConstructEmptyOrTombstoneTy, char *EmptyOrTombstonePtr)
+ : P(EmptyOrTombstonePtr), Size(0), Hash(0) {
+ assert(isEmptyOrTombstone());
+ }
+
+ // TODO: Use small-string optimization to avoid allocating.
+
+public:
+ explicit CachedHashString(const char *S) : CachedHashString(StringRef(S)) {}
+
+ // Explicit because copying and hashing a string isn't free.
+ explicit CachedHashString(StringRef S)
+ : CachedHashString(S, DenseMapInfo<StringRef>::getHashValue(S)) {}
+
+ CachedHashString(StringRef S, uint32_t Hash)
+ : P(new char[S.size()]), Size(S.size()), Hash(Hash) {
+ memcpy(P, S.data(), S.size());
+ }
+
+ // Ideally this class would not be copyable. But SetVector requires copyable
+ // keys, and we want this to be usable there.
+ CachedHashString(const CachedHashString &Other)
+ : Size(Other.Size), Hash(Other.Hash) {
+ if (Other.isEmptyOrTombstone()) {
+ P = Other.P;
+ } else {
+ P = new char[Size];
+ memcpy(P, Other.P, Size);
+ }
+ }
+
+ CachedHashString &operator=(CachedHashString Other) {
+ swap(*this, Other);
+ return *this;
+ }
+
+ CachedHashString(CachedHashString &&Other) noexcept
+ : P(Other.P), Size(Other.Size), Hash(Other.Hash) {
+ Other.P = getEmptyKeyPtr();
+ }
+
+ ~CachedHashString() {
+ if (!isEmptyOrTombstone())
+ delete[] P;
+ }
+
+ StringRef val() const { return StringRef(P, Size); }
+ uint32_t size() const { return Size; }
+ uint32_t hash() const { return Hash; }
+
+ operator StringRef() const { return val(); }
+ operator CachedHashStringRef() const {
+ return CachedHashStringRef(val(), Hash);
+ }
+
+ friend void swap(CachedHashString &LHS, CachedHashString &RHS) {
+ using std::swap;
+ swap(LHS.P, RHS.P);
+ swap(LHS.Size, RHS.Size);
+ swap(LHS.Hash, RHS.Hash);
+ }
+};
+
+template <> struct DenseMapInfo<CachedHashString> {
+ static CachedHashString getEmptyKey() {
+ return CachedHashString(CachedHashString::ConstructEmptyOrTombstoneTy(),
+ CachedHashString::getEmptyKeyPtr());
+ }
+ static CachedHashString getTombstoneKey() {
+ return CachedHashString(CachedHashString::ConstructEmptyOrTombstoneTy(),
+ CachedHashString::getTombstoneKeyPtr());
+ }
+ static unsigned getHashValue(const CachedHashString &S) {
+ assert(!isEqual(S, getEmptyKey()) && "Cannot hash the empty key!");
+ assert(!isEqual(S, getTombstoneKey()) && "Cannot hash the tombstone key!");
+ return S.hash();
+ }
+ static bool isEqual(const CachedHashString &LHS,
+ const CachedHashString &RHS) {
+ if (LHS.hash() != RHS.hash())
+ return false;
+ if (LHS.P == CachedHashString::getEmptyKeyPtr())
+ return RHS.P == CachedHashString::getEmptyKeyPtr();
+ if (LHS.P == CachedHashString::getTombstoneKeyPtr())
+ return RHS.P == CachedHashString::getTombstoneKeyPtr();
+
+ // This is safe because if RHS.P is the empty or tombstone key, it will have
+ // length 0, so we'll never dereference its pointer.
+ return LHS.val() == RHS.val();
+ }
+};
+
+} // namespace llvm
+
+#endif
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif