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-rw-r--r--third_party/abseil_cpp/absl/random/log_uniform_int_distribution.h254
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diff --git a/third_party/abseil_cpp/absl/random/log_uniform_int_distribution.h b/third_party/abseil_cpp/absl/random/log_uniform_int_distribution.h
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index 960816e2f8..0000000000
--- a/third_party/abseil_cpp/absl/random/log_uniform_int_distribution.h
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@@ -1,254 +0,0 @@
-// Copyright 2017 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_RANDOM_LOG_UNIFORM_INT_DISTRIBUTION_H_
-#define ABSL_RANDOM_LOG_UNIFORM_INT_DISTRIBUTION_H_
-
-#include <algorithm>
-#include <cassert>
-#include <cmath>
-#include <istream>
-#include <limits>
-#include <ostream>
-#include <type_traits>
-
-#include "absl/random/internal/fastmath.h"
-#include "absl/random/internal/generate_real.h"
-#include "absl/random/internal/iostream_state_saver.h"
-#include "absl/random/internal/traits.h"
-#include "absl/random/uniform_int_distribution.h"
-
-namespace absl {
-ABSL_NAMESPACE_BEGIN
-
-// log_uniform_int_distribution:
-//
-// Returns a random variate R in range [min, max] such that
-// floor(log(R-min, base)) is uniformly distributed.
-// We ensure uniformity by discretization using the
-// boundary sets [0, 1, base, base * base, ... min(base*n, max)]
-//
-template <typename IntType = int>
-class log_uniform_int_distribution {
- private:
-  using unsigned_type =
-      typename random_internal::make_unsigned_bits<IntType>::type;
-
- public:
-  using result_type = IntType;
-
-  class param_type {
-   public:
-    using distribution_type = log_uniform_int_distribution;
-
-    explicit param_type(
-        result_type min = 0,
-        result_type max = (std::numeric_limits<result_type>::max)(),
-        result_type base = 2)
-        : min_(min),
-          max_(max),
-          base_(base),
-          range_(static_cast<unsigned_type>(max_) -
-                 static_cast<unsigned_type>(min_)),
-          log_range_(0) {
-      assert(max_ >= min_);
-      assert(base_ > 1);
-
-      if (base_ == 2) {
-        // Determine where the first set bit is on range(), giving a log2(range)
-        // value which can be used to construct bounds.
-        log_range_ = (std::min)(random_internal::LeadingSetBit(range()),
-                                std::numeric_limits<unsigned_type>::digits);
-      } else {
-        // NOTE: Computing the logN(x) introduces error from 2 sources:
-        // 1. Conversion of int to double loses precision for values >=
-        // 2^53, which may cause some log() computations to operate on
-        // different values.
-        // 2. The error introduced by the division will cause the result
-        // to differ from the expected value.
-        //
-        // Thus a result which should equal K may equal K +/- epsilon,
-        // which can eliminate some values depending on where the bounds fall.
-        const double inv_log_base = 1.0 / std::log(base_);
-        const double log_range = std::log(static_cast<double>(range()) + 0.5);
-        log_range_ = static_cast<int>(std::ceil(inv_log_base * log_range));
-      }
-    }
-
-    result_type(min)() const { return min_; }
-    result_type(max)() const { return max_; }
-    result_type base() const { return base_; }
-
-    friend bool operator==(const param_type& a, const param_type& b) {
-      return a.min_ == b.min_ && a.max_ == b.max_ && a.base_ == b.base_;
-    }
-
-    friend bool operator!=(const param_type& a, const param_type& b) {
-      return !(a == b);
-    }
-
-   private:
-    friend class log_uniform_int_distribution;
-
-    int log_range() const { return log_range_; }
-    unsigned_type range() const { return range_; }
-
-    result_type min_;
-    result_type max_;
-    result_type base_;
-    unsigned_type range_;  // max - min
-    int log_range_;        // ceil(logN(range_))
-
-    static_assert(std::is_integral<IntType>::value,
-                  "Class-template absl::log_uniform_int_distribution<> must be "
-                  "parameterized using an integral type.");
-  };
-
-  log_uniform_int_distribution() : log_uniform_int_distribution(0) {}
-
-  explicit log_uniform_int_distribution(
-      result_type min,
-      result_type max = (std::numeric_limits<result_type>::max)(),
-      result_type base = 2)
-      : param_(min, max, base) {}
-
-  explicit log_uniform_int_distribution(const param_type& p) : param_(p) {}
-
-  void reset() {}
-
-  // generating functions
-  template <typename URBG>
-  result_type operator()(URBG& g) {  // NOLINT(runtime/references)
-    return (*this)(g, param_);
-  }
-
-  template <typename URBG>
-  result_type operator()(URBG& g,  // NOLINT(runtime/references)
-                         const param_type& p) {
-    return (p.min)() + Generate(g, p);
-  }
-
-  result_type(min)() const { return (param_.min)(); }
-  result_type(max)() const { return (param_.max)(); }
-  result_type base() const { return param_.base(); }
-
-  param_type param() const { return param_; }
-  void param(const param_type& p) { param_ = p; }
-
-  friend bool operator==(const log_uniform_int_distribution& a,
-                         const log_uniform_int_distribution& b) {
-    return a.param_ == b.param_;
-  }
-  friend bool operator!=(const log_uniform_int_distribution& a,
-                         const log_uniform_int_distribution& b) {
-    return a.param_ != b.param_;
-  }
-
- private:
-  // Returns a log-uniform variate in the range [0, p.range()]. The caller
-  // should add min() to shift the result to the correct range.
-  template <typename URNG>
-  unsigned_type Generate(URNG& g,  // NOLINT(runtime/references)
-                         const param_type& p);
-
-  param_type param_;
-};
-
-template <typename IntType>
-template <typename URBG>
-typename log_uniform_int_distribution<IntType>::unsigned_type
-log_uniform_int_distribution<IntType>::Generate(
-    URBG& g,  // NOLINT(runtime/references)
-    const param_type& p) {
-  // sample e over [0, log_range]. Map the results of e to this:
-  // 0 => 0
-  // 1 => [1, b-1]
-  // 2 => [b, (b^2)-1]
-  // n => [b^(n-1)..(b^n)-1]
-  const int e = absl::uniform_int_distribution<int>(0, p.log_range())(g);
-  if (e == 0) {
-    return 0;
-  }
-  const int d = e - 1;
-
-  unsigned_type base_e, top_e;
-  if (p.base() == 2) {
-    base_e = static_cast<unsigned_type>(1) << d;
-
-    top_e = (e >= std::numeric_limits<unsigned_type>::digits)
-                ? (std::numeric_limits<unsigned_type>::max)()
-                : (static_cast<unsigned_type>(1) << e) - 1;
-  } else {
-    const double r = std::pow(p.base(), d);
-    const double s = (r * p.base()) - 1.0;
-
-    base_e =
-        (r > static_cast<double>((std::numeric_limits<unsigned_type>::max)()))
-            ? (std::numeric_limits<unsigned_type>::max)()
-            : static_cast<unsigned_type>(r);
-
-    top_e =
-        (s > static_cast<double>((std::numeric_limits<unsigned_type>::max)()))
-            ? (std::numeric_limits<unsigned_type>::max)()
-            : static_cast<unsigned_type>(s);
-  }
-
-  const unsigned_type lo = (base_e >= p.range()) ? p.range() : base_e;
-  const unsigned_type hi = (top_e >= p.range()) ? p.range() : top_e;
-
-  // choose uniformly over [lo, hi]
-  return absl::uniform_int_distribution<result_type>(lo, hi)(g);
-}
-
-template <typename CharT, typename Traits, typename IntType>
-std::basic_ostream<CharT, Traits>& operator<<(
-    std::basic_ostream<CharT, Traits>& os,  // NOLINT(runtime/references)
-    const log_uniform_int_distribution<IntType>& x) {
-  using stream_type =
-      typename random_internal::stream_format_type<IntType>::type;
-  auto saver = random_internal::make_ostream_state_saver(os);
-  os << static_cast<stream_type>((x.min)()) << os.fill()
-     << static_cast<stream_type>((x.max)()) << os.fill()
-     << static_cast<stream_type>(x.base());
-  return os;
-}
-
-template <typename CharT, typename Traits, typename IntType>
-std::basic_istream<CharT, Traits>& operator>>(
-    std::basic_istream<CharT, Traits>& is,       // NOLINT(runtime/references)
-    log_uniform_int_distribution<IntType>& x) {  // NOLINT(runtime/references)
-  using param_type = typename log_uniform_int_distribution<IntType>::param_type;
-  using result_type =
-      typename log_uniform_int_distribution<IntType>::result_type;
-  using stream_type =
-      typename random_internal::stream_format_type<IntType>::type;
-
-  stream_type min;
-  stream_type max;
-  stream_type base;
-
-  auto saver = random_internal::make_istream_state_saver(is);
-  is >> min >> max >> base;
-  if (!is.fail()) {
-    x.param(param_type(static_cast<result_type>(min),
-                       static_cast<result_type>(max),
-                       static_cast<result_type>(base)));
-  }
-  return is;
-}
-
-ABSL_NAMESPACE_END
-}  // namespace absl
-
-#endif  // ABSL_RANDOM_LOG_UNIFORM_INT_DISTRIBUTION_H_