intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 561 insertions, 0 deletions

diff --git a/contrib/libs/cxxsupp/libcxx/src/hash.cpp b/contrib/libs/cxxsupp/libcxx/src/hash.cpp
new file mode 100644
index 0000000000..89bb736c86
--- /dev/null
+++ b/contrib/libs/cxxsupp/libcxx/src/hash.cpp
@@ -0,0 +1,561 @@
+//===-------------------------- hash.cpp ----------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "__hash_table"
+#include "algorithm"
+#include "stdexcept"
+#include "type_traits"
+
+#ifdef __clang__
+#pragma clang diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace {
+
+// handle all next_prime(i) for i in [1, 210), special case 0
+const unsigned small_primes[] =
+{
+    0,
+    2,
+    3,
+    5,
+    7,
+    11,
+    13,
+    17,
+    19,
+    23,
+    29,
+    31,
+    37,
+    41,
+    43,
+    47,
+    53,
+    59,
+    61,
+    67,
+    71,
+    73,
+    79,
+    83,
+    89,
+    97,
+    101,
+    103,
+    107,
+    109,
+    113,
+    127,
+    131,
+    137,
+    139,
+    149,
+    151,
+    157,
+    163,
+    167,
+    173,
+    179,
+    181,
+    191,
+    193,
+    197,
+    199,
+    211
+};
+
+// potential primes = 210*k + indices[i], k >= 1
+//   these numbers are not divisible by 2, 3, 5 or 7
+//   (or any integer 2 <= j <= 10 for that matter).
+const unsigned indices[] =
+{
+    1,
+    11,
+    13,
+    17,
+    19,
+    23,
+    29,
+    31,
+    37,
+    41,
+    43,
+    47,
+    53,
+    59,
+    61,
+    67,
+    71,
+    73,
+    79,
+    83,
+    89,
+    97,
+    101,
+    103,
+    107,
+    109,
+    113,
+    121,
+    127,
+    131,
+    137,
+    139,
+    143,
+    149,
+    151,
+    157,
+    163,
+    167,
+    169,
+    173,
+    179,
+    181,
+    187,
+    191,
+    193,
+    197,
+    199,
+    209
+};
+
+}
+
+// Returns:  If n == 0, returns 0.  Else returns the lowest prime number that
+// is greater than or equal to n.
+//
+// The algorithm creates a list of small primes, plus an open-ended list of
+// potential primes.  All prime numbers are potential prime numbers.  However
+// some potential prime numbers are not prime.  In an ideal world, all potential
+// prime numbers would be prime.  Candidate prime numbers are chosen as the next
+// highest potential prime.  Then this number is tested for prime by dividing it
+// by all potential prime numbers less than the sqrt of the candidate.
+//
+// This implementation defines potential primes as those numbers not divisible
+// by 2, 3, 5, and 7.  Other (common) implementations define potential primes
+// as those not divisible by 2.  A few other implementations define potential
+// primes as those not divisible by 2 or 3.  By raising the number of small
+// primes which the potential prime is not divisible by, the set of potential
+// primes more closely approximates the set of prime numbers.  And thus there
+// are fewer potential primes to search, and fewer potential primes to divide
+// against.
+
+template <size_t _Sz = sizeof(size_t)>
+inline _LIBCPP_INLINE_VISIBILITY
+typename enable_if<_Sz == 4, void>::type
+__check_for_overflow(size_t N)
+{
+    if (N > 0xFFFFFFFB)
+        __throw_overflow_error("__next_prime overflow");
+}
+
+template <size_t _Sz = sizeof(size_t)>
+inline _LIBCPP_INLINE_VISIBILITY
+typename enable_if<_Sz == 8, void>::type
+__check_for_overflow(size_t N)
+{
+    if (N > 0xFFFFFFFFFFFFFFC5ull)
+        __throw_overflow_error("__next_prime overflow");
+}
+
+size_t
+__next_prime(size_t n)
+{
+    const size_t L = 210;
+    const size_t N = sizeof(small_primes) / sizeof(small_primes[0]);
+    // If n is small enough, search in small_primes
+    if (n <= small_primes[N-1])
+        return *std::lower_bound(small_primes, small_primes + N, n);
+    // Else n > largest small_primes
+    // Check for overflow
+    __check_for_overflow(n);
+    // Start searching list of potential primes: L * k0 + indices[in]
+    const size_t M = sizeof(indices) / sizeof(indices[0]);
+    // Select first potential prime >= n
+    //   Known a-priori n >= L
+    size_t k0 = n / L;
+    size_t in = static_cast<size_t>(std::lower_bound(indices, indices + M, n - k0 * L)
+                                    - indices);
+    n = L * k0 + indices[in];
+    while (true)
+    {
+        // Divide n by all primes or potential primes (i) until:
+        //    1.  The division is even, so try next potential prime.
+        //    2.  The i > sqrt(n), in which case n is prime.
+        // It is known a-priori that n is not divisible by 2, 3, 5 or 7,
+        //    so don't test those (j == 5 ->  divide by 11 first).  And the
+        //    potential primes start with 211, so don't test against the last
+        //    small prime.
+        for (size_t j = 5; j < N - 1; ++j)
+        {
+            const std::size_t p = small_primes[j];
+            const std::size_t q = n / p;
+            if (q < p)
+                return n;
+            if (n == q * p)
+                goto next;
+        }
+        // n wasn't divisible by small primes, try potential primes
+        {
+            size_t i = 211;
+            while (true)
+            {
+                std::size_t q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 10;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 8;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 8;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 6;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 4;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 2;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                i += 10;
+                q = n / i;
+                if (q < i)
+                    return n;
+                if (n == q * i)
+                    break;
+
+                // This will loop i to the next "plane" of potential primes
+                i += 2;
+            }
+        }
+next:
+        // n is not prime.  Increment n to next potential prime.
+        if (++in == M)
+        {
+            ++k0;
+            in = 0;
+        }
+        n = L * k0 + indices[in];
+    }
+}
+
+_LIBCPP_END_NAMESPACE_STD