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diff --git a/contrib/llvm-project/llvm/lib/Support/OptimizedStructLayout.cpp b/contrib/llvm-project/llvm/lib/Support/OptimizedStructLayout.cpp
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+++ b/contrib/llvm-project/llvm/lib/Support/OptimizedStructLayout.cpp
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+//===--- OptimizedStructLayout.cpp - Optimal data layout algorithm ----------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the performOptimizedStructLayout interface.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/OptimizedStructLayout.h"
+#include <optional>
+
+using namespace llvm;
+
+using Field = OptimizedStructLayoutField;
+
+#ifndef NDEBUG
+static void checkValidLayout(ArrayRef<Field> Fields, uint64_t Size,
+                             Align MaxAlign) {
+  uint64_t LastEnd = 0;
+  Align ComputedMaxAlign;
+  for (auto &Field : Fields) {
+    assert(Field.hasFixedOffset() &&
+           "didn't assign a fixed offset to field");
+    assert(isAligned(Field.Alignment, Field.Offset) &&
+           "didn't assign a correctly-aligned offset to field");
+    assert(Field.Offset >= LastEnd &&
+           "didn't assign offsets in ascending order");
+    LastEnd = Field.getEndOffset();
+    assert(Field.Alignment <= MaxAlign &&
+           "didn't compute MaxAlign correctly");
+    ComputedMaxAlign = std::max(Field.Alignment, MaxAlign);
+  }
+  assert(LastEnd == Size && "didn't compute LastEnd correctly");
+  assert(ComputedMaxAlign == MaxAlign && "didn't compute MaxAlign correctly");
+}
+#endif
+
+std::pair<uint64_t, Align>
+llvm::performOptimizedStructLayout(MutableArrayRef<Field> Fields) {
+#ifndef NDEBUG
+  // Do some simple precondition checks.
+  {
+    bool InFixedPrefix = true;
+    size_t LastEnd = 0;
+    for (auto &Field : Fields) {
+      assert(Field.Size > 0 && "field of zero size");
+      if (Field.hasFixedOffset()) {
+        assert(InFixedPrefix &&
+               "fixed-offset fields are not a strict prefix of array");
+        assert(LastEnd <= Field.Offset &&
+               "fixed-offset fields overlap or are not in order");
+        LastEnd = Field.getEndOffset();
+        assert(LastEnd > Field.Offset &&
+               "overflow in fixed-offset end offset");
+      } else {
+        InFixedPrefix = false;
+      }
+    }
+  }
+#endif
+
+  // Do an initial pass over the fields.
+  Align MaxAlign;
+
+  // Find the first flexible-offset field, tracking MaxAlign.
+  auto FirstFlexible = Fields.begin(), E = Fields.end();
+  while (FirstFlexible != E && FirstFlexible->hasFixedOffset()) {
+    MaxAlign = std::max(MaxAlign, FirstFlexible->Alignment);
+    ++FirstFlexible;
+  }
+
+  // If there are no flexible fields, we're done.
+  if (FirstFlexible == E) {
+    uint64_t Size = 0;
+    if (!Fields.empty())
+      Size = Fields.back().getEndOffset();
+
+#ifndef NDEBUG
+    checkValidLayout(Fields, Size, MaxAlign);
+#endif
+    return std::make_pair(Size, MaxAlign);
+  }
+
+  // Walk over the flexible-offset fields, tracking MaxAlign and
+  // assigning them a unique number in order of their appearance.
+  // We'll use this unique number in the comparison below so that
+  // we can use array_pod_sort, which isn't stable.  We won't use it
+  // past that point.
+  {
+    uintptr_t UniqueNumber = 0;
+    for (auto I = FirstFlexible; I != E; ++I) {
+      I->Scratch = reinterpret_cast<void*>(UniqueNumber++);
+      MaxAlign = std::max(MaxAlign, I->Alignment);
+    }
+  }
+
+  // Sort the flexible elements in order of decreasing alignment,
+  // then decreasing size, and then the original order as recorded
+  // in Scratch.  The decreasing-size aspect of this is only really
+  // important if we get into the gap-filling stage below, but it
+  // doesn't hurt here.
+  array_pod_sort(FirstFlexible, E,
+                 [](const Field *lhs, const Field *rhs) -> int {
+    // Decreasing alignment.
+    if (lhs->Alignment != rhs->Alignment)
+      return (lhs->Alignment < rhs->Alignment ? 1 : -1);
+
+    // Decreasing size.
+    if (lhs->Size != rhs->Size)
+      return (lhs->Size < rhs->Size ? 1 : -1);
+
+    // Original order.
+    auto lhsNumber = reinterpret_cast<uintptr_t>(lhs->Scratch);
+    auto rhsNumber = reinterpret_cast<uintptr_t>(rhs->Scratch);
+    if (lhsNumber != rhsNumber)
+      return (lhsNumber < rhsNumber ? -1 : 1);
+
+    return 0;
+  });
+
+  // Do a quick check for whether that sort alone has given us a perfect
+  // layout with no interior padding.  This is very common: if the
+  // fixed-layout fields have no interior padding, and they end at a
+  // sufficiently-aligned offset for all the flexible-layout fields,
+  // and the flexible-layout fields all have sizes that are multiples
+  // of their alignment, then this will reliably trigger.
+  {
+    bool HasPadding = false;
+    uint64_t LastEnd = 0;
+
+    // Walk the fixed-offset fields.
+    for (auto I = Fields.begin(); I != FirstFlexible; ++I) {
+      assert(I->hasFixedOffset());
+      if (LastEnd != I->Offset) {
+        HasPadding = true;
+        break;
+      }
+      LastEnd = I->getEndOffset();
+    }
+
+    // Walk the flexible-offset fields, optimistically assigning fixed
+    // offsets.  Note that we maintain a strict division between the
+    // fixed-offset and flexible-offset fields, so if we end up
+    // discovering padding later in this loop, we can just abandon this
+    // work and we'll ignore the offsets we already assigned.
+    if (!HasPadding) {
+      for (auto I = FirstFlexible; I != E; ++I) {
+        auto Offset = alignTo(LastEnd, I->Alignment);
+        if (LastEnd != Offset) {
+          HasPadding = true;
+          break;
+        }
+        I->Offset = Offset;
+        LastEnd = I->getEndOffset();
+      }
+    }
+
+    // If we already have a perfect layout, we're done.
+    if (!HasPadding) {
+#ifndef NDEBUG
+      checkValidLayout(Fields, LastEnd, MaxAlign);
+#endif
+      return std::make_pair(LastEnd, MaxAlign);
+    }
+  }
+
+  // The algorithm sketch at this point is as follows.
+  //
+  // Consider the padding gaps between fixed-offset fields in ascending
+  // order.  Let LastEnd be the offset of the first byte following the
+  // field before the gap, or 0 if the gap is at the beginning of the
+  // structure.  Find the "best" flexible-offset field according to the
+  // criteria below.  If no such field exists, proceed to the next gap.
+  // Otherwise, add the field at the first properly-aligned offset for
+  // that field that is >= LastEnd, then update LastEnd and repeat in
+  // order to fill any remaining gap following that field.
+  //
+  // Next, let LastEnd to be the offset of the first byte following the
+  // last fixed-offset field, or 0 if there are no fixed-offset fields.
+  // While there are flexible-offset fields remaining, find the "best"
+  // flexible-offset field according to the criteria below, add it at
+  // the first properly-aligned offset for that field that is >= LastEnd,
+  // and update LastEnd to the first byte following the field.
+  //
+  // The "best" field is chosen by the following criteria, considered
+  // strictly in order:
+  //
+  // - When filling a gap betweeen fields, the field must fit.
+  // - A field is preferred if it requires less padding following LastEnd.
+  // - A field is preferred if it is more aligned.
+  // - A field is preferred if it is larger.
+  // - A field is preferred if it appeared earlier in the initial order.
+  //
+  // Minimizing leading padding is a greedy attempt to avoid padding
+  // entirely.  Preferring more-aligned fields is an attempt to eliminate
+  // stricter constraints earlier, with the idea that weaker alignment
+  // constraints may be resolvable with less padding elsewhere.  These
+  // These two rules are sufficient to ensure that we get the optimal
+  // layout in the "C-style" case.  Preferring larger fields tends to take
+  // better advantage of large gaps and may be more likely to have a size
+  // that's a multiple of a useful alignment.  Preferring the initial
+  // order may help somewhat with locality but is mostly just a way of
+  // ensuring deterministic output.
+  //
+  // Note that this algorithm does not guarantee a minimal layout.  Picking
+  // a larger object greedily may leave a gap that cannot be filled as
+  // efficiently.  Unfortunately, solving this perfectly is an NP-complete
+  // problem (by reduction from bin-packing: let B_i be the bin sizes and
+  // O_j be the object sizes; add fixed-offset fields such that the gaps
+  // between them have size B_i, and add flexible-offset fields with
+  // alignment 1 and size O_j; if the layout size is equal to the end of
+  // the last fixed-layout field, the objects fit in the bins; note that
+  // this doesn't even require the complexity of alignment).
+
+  // The implementation below is essentially just an optimized version of
+  // scanning the list of remaining fields looking for the best, which
+  // would be O(n^2).  In the worst case, it doesn't improve on that.
+  // However, in practice it'll just scan the array of alignment bins
+  // and consider the first few elements from one or two bins.  The
+  // number of bins is bounded by a small constant: alignments are powers
+  // of two that are vanishingly unlikely to be over 64 and fairly unlikely
+  // to be over 8.  And multiple elements only need to be considered when
+  // filling a gap between fixed-offset fields, which doesn't happen very
+  // often.  We could use a data structure within bins that optimizes for
+  // finding the best-sized match, but it would require allocating memory
+  // and copying data, so it's unlikely to be worthwhile.
+
+
+  // Start by organizing the flexible-offset fields into bins according to
+  // their alignment.  We expect a small enough number of bins that we
+  // don't care about the asymptotic costs of walking this.
+  struct AlignmentQueue {
+    /// The minimum size of anything currently in this queue.
+    uint64_t MinSize;
+
+    /// The head of the queue.  A singly-linked list.  The order here should
+    /// be consistent with the earlier sort, i.e. the elements should be
+    /// monotonically descending in size and otherwise in the original order.
+    ///
+    /// We remove the queue from the array as soon as this is empty.
+    OptimizedStructLayoutField *Head;
+
+    /// The alignment requirement of the queue.
+    Align Alignment;
+
+    static Field *getNext(Field *Cur) {
+      return static_cast<Field *>(Cur->Scratch);
+    }
+  };
+  SmallVector<AlignmentQueue, 8> FlexibleFieldsByAlignment;
+  for (auto I = FirstFlexible; I != E; ) {
+    auto Head = I;
+    auto Alignment = I->Alignment;
+
+    uint64_t MinSize = I->Size;
+    auto LastInQueue = I;
+    for (++I; I != E && I->Alignment == Alignment; ++I) {
+      LastInQueue->Scratch = I;
+      LastInQueue = I;
+      MinSize = std::min(MinSize, I->Size);
+    }
+    LastInQueue->Scratch = nullptr;
+
+    FlexibleFieldsByAlignment.push_back({MinSize, Head, Alignment});
+  }
+
+#ifndef NDEBUG
+  // Verify that we set the queues up correctly.
+  auto checkQueues = [&]{
+    bool FirstQueue = true;
+    Align LastQueueAlignment;
+    for (auto &Queue : FlexibleFieldsByAlignment) {
+      assert((FirstQueue || Queue.Alignment < LastQueueAlignment) &&
+             "bins not in order of descending alignment");
+      LastQueueAlignment = Queue.Alignment;
+      FirstQueue = false;
+
+      assert(Queue.Head && "queue was empty");
+      uint64_t LastSize = ~(uint64_t)0;
+      for (auto I = Queue.Head; I; I = Queue.getNext(I)) {
+        assert(I->Alignment == Queue.Alignment && "bad field in queue");
+        assert(I->Size <= LastSize && "queue not in descending size order");
+        LastSize = I->Size;
+      }
+    }
+  };
+  checkQueues();
+#endif
+
+  /// Helper function to remove a field from a queue.
+  auto spliceFromQueue = [&](AlignmentQueue *Queue, Field *Last, Field *Cur) {
+    assert(Last ? Queue->getNext(Last) == Cur : Queue->Head == Cur);
+
+    // If we're removing Cur from a non-initial position, splice it out
+    // of the linked list.
+    if (Last) {
+      Last->Scratch = Cur->Scratch;
+
+      // If Cur was the last field in the list, we need to update MinSize.
+      // We can just use the last field's size because the list is in
+      // descending order of size.
+      if (!Cur->Scratch)
+        Queue->MinSize = Last->Size;
+
+    // Otherwise, replace the head.
+    } else {
+      if (auto NewHead = Queue->getNext(Cur))
+        Queue->Head = NewHead;
+
+      // If we just emptied the queue, destroy its bin.
+      else
+        FlexibleFieldsByAlignment.erase(Queue);
+    }
+  };
+
+  // Do layout into a local array.  Doing this in-place on Fields is
+  // not really feasible.
+  SmallVector<Field, 16> Layout;
+  Layout.reserve(Fields.size());
+
+  // The offset that we're currently looking to insert at (or after).
+  uint64_t LastEnd = 0;
+
+  // Helper function to splice Cur out of the given queue and add it
+  // to the layout at the given offset.
+  auto addToLayout = [&](AlignmentQueue *Queue, Field *Last, Field *Cur,
+                         uint64_t Offset) -> bool {
+    assert(Offset == alignTo(LastEnd, Cur->Alignment));
+
+    // Splice out.  This potentially invalidates Queue.
+    spliceFromQueue(Queue, Last, Cur);
+
+    // Add Cur to the layout.
+    Layout.push_back(*Cur);
+    Layout.back().Offset = Offset;
+    LastEnd = Layout.back().getEndOffset();
+
+    // Always return true so that we can be tail-called.
+    return true;
+  };
+
+  // Helper function to try to find a field in the given queue that'll
+  // fit starting at StartOffset but before EndOffset (if present).
+  // Note that this never fails if EndOffset is not provided.
+  auto tryAddFillerFromQueue = [&](AlignmentQueue *Queue, uint64_t StartOffset,
+                                   std::optional<uint64_t> EndOffset) -> bool {
+    assert(Queue->Head);
+    assert(StartOffset == alignTo(LastEnd, Queue->Alignment));
+    assert(!EndOffset || StartOffset < *EndOffset);
+
+    // Figure out the maximum size that a field can be, and ignore this
+    // queue if there's nothing in it that small.
+    auto MaxViableSize =
+      (EndOffset ? *EndOffset - StartOffset : ~(uint64_t)0);
+    if (Queue->MinSize > MaxViableSize)
+      return false;
+
+    // Find the matching field.  Note that this should always find
+    // something because of the MinSize check above.
+    for (Field *Cur = Queue->Head, *Last = nullptr; true;
+           Last = Cur, Cur = Queue->getNext(Cur)) {
+      assert(Cur && "didn't find a match in queue despite its MinSize");
+      if (Cur->Size <= MaxViableSize)
+        return addToLayout(Queue, Last, Cur, StartOffset);
+    }
+
+    llvm_unreachable("didn't find a match in queue despite its MinSize");
+  };
+
+  // Helper function to find the "best" flexible-offset field according
+  // to the criteria described above.
+  auto tryAddBestField = [&](std::optional<uint64_t> BeforeOffset) -> bool {
+    assert(!BeforeOffset || LastEnd < *BeforeOffset);
+    auto QueueB = FlexibleFieldsByAlignment.begin();
+    auto QueueE = FlexibleFieldsByAlignment.end();
+
+    // Start by looking for the most-aligned queue that doesn't need any
+    // leading padding after LastEnd.
+    auto FirstQueueToSearch = QueueB;
+    for (; FirstQueueToSearch != QueueE; ++FirstQueueToSearch) {
+      if (isAligned(FirstQueueToSearch->Alignment, LastEnd))
+        break;
+    }
+
+    uint64_t Offset = LastEnd;
+    while (true) {
+      // Invariant: all of the queues in [FirstQueueToSearch, QueueE)
+      // require the same initial padding offset.
+
+      // Search those queues in descending order of alignment for a
+      // satisfactory field.
+      for (auto Queue = FirstQueueToSearch; Queue != QueueE; ++Queue) {
+        if (tryAddFillerFromQueue(Queue, Offset, BeforeOffset))
+          return true;
+      }
+
+      // Okay, we don't need to scan those again.
+      QueueE = FirstQueueToSearch;
+
+      // If we started from the first queue, we're done.
+      if (FirstQueueToSearch == QueueB)
+        return false;
+
+      // Otherwise, scan backwards to find the most-aligned queue that
+      // still has minimal leading padding after LastEnd.  If that
+      // minimal padding is already at or past the end point, we're done.
+      --FirstQueueToSearch;
+      Offset = alignTo(LastEnd, FirstQueueToSearch->Alignment);
+      if (BeforeOffset && Offset >= *BeforeOffset)
+        return false;
+      while (FirstQueueToSearch != QueueB &&
+             Offset == alignTo(LastEnd, FirstQueueToSearch[-1].Alignment))
+        --FirstQueueToSearch;
+    }
+  };
+
+  // Phase 1: fill the gaps between fixed-offset fields with the best
+  // flexible-offset field that fits.
+  for (auto I = Fields.begin(); I != FirstFlexible; ++I) {
+    assert(LastEnd <= I->Offset);
+    while (LastEnd != I->Offset) {
+      if (!tryAddBestField(I->Offset))
+        break;
+    }
+    Layout.push_back(*I);
+    LastEnd = I->getEndOffset();
+  }
+
+#ifndef NDEBUG
+  checkQueues();
+#endif
+
+  // Phase 2: repeatedly add the best flexible-offset field until
+  // they're all gone.
+  while (!FlexibleFieldsByAlignment.empty()) {
+    bool Success = tryAddBestField(std::nullopt);
+    assert(Success && "didn't find a field with no fixed limit?");
+    (void) Success;
+  }
+
+  // Copy the layout back into place.
+  assert(Layout.size() == Fields.size());
+  memcpy(Fields.data(), Layout.data(),
+         Fields.size() * sizeof(OptimizedStructLayoutField));
+
+#ifndef NDEBUG
+  // Make a final check that the layout is valid.
+  checkValidLayout(Fields, LastEnd, MaxAlign);
+#endif
+
+  return std::make_pair(LastEnd, MaxAlign);
+}