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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/FuzzMutate/Random.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/FuzzMutate/Random.h')
-rw-r--r--contrib/libs/llvm14/include/llvm/FuzzMutate/Random.h107
1 files changed, 107 insertions, 0 deletions
diff --git a/contrib/libs/llvm14/include/llvm/FuzzMutate/Random.h b/contrib/libs/llvm14/include/llvm/FuzzMutate/Random.h
new file mode 100644
index 0000000000..2f04bf63b1
--- /dev/null
+++ b/contrib/libs/llvm14/include/llvm/FuzzMutate/Random.h
@@ -0,0 +1,107 @@
+#pragma once
+
+#ifdef __GNUC__
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Wunused-parameter"
+#endif
+
+//===--- Random.h - Utilities for random sampling -------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Utilities for random sampling.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_FUZZMUTATE_RANDOM_H
+#define LLVM_FUZZMUTATE_RANDOM_H
+
+#include <random>
+#include "llvm/Support/raw_ostream.h"
+namespace llvm {
+
+/// Return a uniformly distributed random value between \c Min and \c Max
+template <typename T, typename GenT> T uniform(GenT &Gen, T Min, T Max) {
+ return std::uniform_int_distribution<T>(Min, Max)(Gen);
+}
+
+/// Return a uniformly distributed random value of type \c T
+template <typename T, typename GenT> T uniform(GenT &Gen) {
+ return uniform<T>(Gen, std::numeric_limits<T>::min(),
+ std::numeric_limits<T>::max());
+}
+
+/// Randomly selects an item by sampling into a set with an unknown number of
+/// elements, which may each be weighted to be more likely choices.
+template <typename T, typename GenT> class ReservoirSampler {
+ GenT &RandGen;
+ std::remove_const_t<T> Selection = {};
+ uint64_t TotalWeight = 0;
+
+public:
+ ReservoirSampler(GenT &RandGen) : RandGen(RandGen) {}
+
+ uint64_t totalWeight() const { return TotalWeight; }
+ bool isEmpty() const { return TotalWeight == 0; }
+
+ const T &getSelection() const {
+ assert(!isEmpty() && "Nothing selected");
+ return Selection;
+ }
+
+ explicit operator bool() const { return !isEmpty();}
+ const T &operator*() const { return getSelection(); }
+
+ /// Sample each item in \c Items with unit weight
+ template <typename RangeT> ReservoirSampler &sample(RangeT &&Items) {
+ for (auto &I : Items)
+ sample(I, 1);
+ return *this;
+ }
+
+ /// Sample a single item with the given weight.
+ ReservoirSampler &sample(const T &Item, uint64_t Weight) {
+ if (!Weight)
+ // If the weight is zero, do nothing.
+ return *this;
+ TotalWeight += Weight;
+ // Consider switching from the current element to this one.
+ if (uniform<uint64_t>(RandGen, 1, TotalWeight) <= Weight)
+ Selection = Item;
+ return *this;
+ }
+};
+
+template <typename GenT, typename RangeT,
+ typename ElT = std::remove_reference_t<
+ decltype(*std::begin(std::declval<RangeT>()))>>
+ReservoirSampler<ElT, GenT> makeSampler(GenT &RandGen, RangeT &&Items) {
+ ReservoirSampler<ElT, GenT> RS(RandGen);
+ RS.sample(Items);
+ return RS;
+}
+
+template <typename GenT, typename T>
+ReservoirSampler<T, GenT> makeSampler(GenT &RandGen, const T &Item,
+ uint64_t Weight) {
+ ReservoirSampler<T, GenT> RS(RandGen);
+ RS.sample(Item, Weight);
+ return RS;
+}
+
+template <typename T, typename GenT>
+ReservoirSampler<T, GenT> makeSampler(GenT &RandGen) {
+ return ReservoirSampler<T, GenT>(RandGen);
+}
+
+} // End llvm namespace
+
+#endif // LLVM_FUZZMUTATE_RANDOM_H
+
+#ifdef __GNUC__
+#pragma GCC diagnostic pop
+#endif