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diff --git a/vendor/ar_archive_writer/src/Alignment.h b/vendor/ar_archive_writer/src/Alignment.h
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+// Copied from https://github.com/llvm/llvm-project/blob/3d3ef9d073e1e27ea57480b371b7f5a9f5642ed2/llvm/include/llvm/Support/Alignment.h
+
+//===-- llvm/Support/Alignment.h - Useful alignment functions ---*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains types to represent alignments.
+// They are instrumented to guarantee some invariants are preserved and prevent
+// invalid manipulations.
+//
+// - Align represents an alignment in bytes, it is always set and always a valid
+// power of two, its minimum value is 1 which means no alignment requirements.
+//
+// - MaybeAlign is an optional type, it may be undefined or set. When it's set
+// you can get the underlying Align type by using the getValue() method.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_SUPPORT_ALIGNMENT_H_
+#define LLVM_SUPPORT_ALIGNMENT_H_
+
+#include "llvm/ADT/Optional.h"
+#include "llvm/Support/MathExtras.h"
+#include <cassert>
+#ifndef NDEBUG
+#include <string>
+#endif // NDEBUG
+
+namespace llvm {
+
+#define ALIGN_CHECK_ISPOSITIVE(decl)                                           \
+  assert(decl > 0 && (#decl " should be defined"))
+
+/// This struct is a compact representation of a valid (non-zero power of two)
+/// alignment.
+/// It is suitable for use as static global constants.
+struct Align {
+private:
+  uint8_t ShiftValue = 0; /// The log2 of the required alignment.
+                          /// ShiftValue is less than 64 by construction.
+
+  friend struct MaybeAlign;
+  friend unsigned Log2(Align);
+  friend bool operator==(Align Lhs, Align Rhs);
+  friend bool operator!=(Align Lhs, Align Rhs);
+  friend bool operator<=(Align Lhs, Align Rhs);
+  friend bool operator>=(Align Lhs, Align Rhs);
+  friend bool operator<(Align Lhs, Align Rhs);
+  friend bool operator>(Align Lhs, Align Rhs);
+  friend unsigned encode(struct MaybeAlign A);
+  friend struct MaybeAlign decodeMaybeAlign(unsigned Value);
+
+  /// A trivial type to allow construction of constexpr Align.
+  /// This is currently needed to workaround a bug in GCC 5.3 which prevents
+  /// definition of constexpr assign operators.
+  /// https://stackoverflow.com/questions/46756288/explicitly-defaulted-function-cannot-be-declared-as-constexpr-because-the-implic
+  /// FIXME: Remove this, make all assign operators constexpr and introduce user
+  /// defined literals when we don't have to support GCC 5.3 anymore.
+  /// https://llvm.org/docs/GettingStarted.html#getting-a-modern-host-c-toolchain
+  struct LogValue {
+    uint8_t Log;
+  };
+
+public:
+  /// Default is byte-aligned.
+  constexpr Align() = default;
+  /// Do not perform checks in case of copy/move construct/assign, because the
+  /// checks have been performed when building `Other`.
+  constexpr Align(const Align &Other) = default;
+  constexpr Align(Align &&Other) = default;
+  Align &operator=(const Align &Other) = default;
+  Align &operator=(Align &&Other) = default;
+
+  explicit Align(uint64_t Value) {
+    assert(Value > 0 && "Value must not be 0");
+    assert(llvm::isPowerOf2_64(Value) && "Alignment is not a power of 2");
+    ShiftValue = Log2_64(Value);
+    assert(ShiftValue < 64 && "Broken invariant");
+  }
+
+  /// This is a hole in the type system and should not be abused.
+  /// Needed to interact with C for instance.
+  uint64_t value() const { return uint64_t(1) << ShiftValue; }
+
+  // Returns the previous alignment.
+  Align previous() const {
+    assert(ShiftValue != 0 && "Undefined operation");
+    Align Out;
+    Out.ShiftValue = ShiftValue - 1;
+    return Out;
+  }
+
+  /// Allow constructions of constexpr Align.
+  template <size_t kValue> constexpr static LogValue Constant() {
+    return LogValue{static_cast<uint8_t>(CTLog2<kValue>())};
+  }
+
+  /// Allow constructions of constexpr Align from types.
+  /// Compile time equivalent to Align(alignof(T)).
+  template <typename T> constexpr static LogValue Of() {
+    return Constant<std::alignment_of<T>::value>();
+  }
+
+  /// Constexpr constructor from LogValue type.
+  constexpr Align(LogValue CA) : ShiftValue(CA.Log) {}
+};
+
+/// Treats the value 0 as a 1, so Align is always at least 1.
+inline Align assumeAligned(uint64_t Value) {
+  return Value ? Align(Value) : Align();
+}
+
+/// This struct is a compact representation of a valid (power of two) or
+/// undefined (0) alignment.
+struct MaybeAlign : public llvm::Optional<Align> {
+private:
+  using UP = llvm::Optional<Align>;
+
+public:
+  /// Default is undefined.
+  MaybeAlign() = default;
+  /// Do not perform checks in case of copy/move construct/assign, because the
+  /// checks have been performed when building `Other`.
+  MaybeAlign(const MaybeAlign &Other) = default;
+  MaybeAlign &operator=(const MaybeAlign &Other) = default;
+  MaybeAlign(MaybeAlign &&Other) = default;
+  MaybeAlign &operator=(MaybeAlign &&Other) = default;
+
+  /// Use llvm::Optional<Align> constructor.
+  using UP::UP;
+
+  explicit MaybeAlign(uint64_t Value) {
+    assert((Value == 0 || llvm::isPowerOf2_64(Value)) &&
+           "Alignment is neither 0 nor a power of 2");
+    if (Value)
+      emplace(Value);
+  }
+
+  /// For convenience, returns a valid alignment or 1 if undefined.
+  Align valueOrOne() const { return value_or(Align()); }
+};
+
+/// Checks that SizeInBytes is a multiple of the alignment.
+inline bool isAligned(Align Lhs, uint64_t SizeInBytes) {
+  return SizeInBytes % Lhs.value() == 0;
+}
+
+/// Checks that Addr is a multiple of the alignment.
+inline bool isAddrAligned(Align Lhs, const void *Addr) {
+  return isAligned(Lhs, reinterpret_cast<uintptr_t>(Addr));
+}
+
+/// Returns a multiple of A needed to store `Size` bytes.
+inline uint64_t alignTo(uint64_t Size, Align A) {
+  const uint64_t Value = A.value();
+  // The following line is equivalent to `(Size + Value - 1) / Value * Value`.
+
+  // The division followed by a multiplication can be thought of as a right
+  // shift followed by a left shift which zeros out the extra bits produced in
+  // the bump; `~(Value - 1)` is a mask where all those bits being zeroed out
+  // are just zero.
+
+  // Most compilers can generate this code but the pattern may be missed when
+  // multiple functions gets inlined.
+  return (Size + Value - 1) & ~(Value - 1U);
+}
+
+/// If non-zero \p Skew is specified, the return value will be a minimal integer
+/// that is greater than or equal to \p Size and equal to \p A * N + \p Skew for
+/// some integer N. If \p Skew is larger than \p A, its value is adjusted to '\p
+/// Skew mod \p A'.
+///
+/// Examples:
+/// \code
+///   alignTo(5, Align(8), 7) = 7
+///   alignTo(17, Align(8), 1) = 17
+///   alignTo(~0LL, Align(8), 3) = 3
+/// \endcode
+inline uint64_t alignTo(uint64_t Size, Align A, uint64_t Skew) {
+  const uint64_t Value = A.value();
+  Skew %= Value;
+  return alignTo(Size - Skew, A) + Skew;
+}
+
+/// Aligns `Addr` to `Alignment` bytes, rounding up.
+inline uintptr_t alignAddr(const void *Addr, Align Alignment) {
+  uintptr_t ArithAddr = reinterpret_cast<uintptr_t>(Addr);
+  assert(static_cast<uintptr_t>(ArithAddr + Alignment.value() - 1) >=
+             ArithAddr &&
+         "Overflow");
+  return alignTo(ArithAddr, Alignment);
+}
+
+/// Returns the offset to the next integer (mod 2**64) that is greater than
+/// or equal to \p Value and is a multiple of \p Align.
+inline uint64_t offsetToAlignment(uint64_t Value, Align Alignment) {
+  return alignTo(Value, Alignment) - Value;
+}
+
+/// Returns the necessary adjustment for aligning `Addr` to `Alignment`
+/// bytes, rounding up.
+inline uint64_t offsetToAlignedAddr(const void *Addr, Align Alignment) {
+  return offsetToAlignment(reinterpret_cast<uintptr_t>(Addr), Alignment);
+}
+
+/// Returns the log2 of the alignment.
+inline unsigned Log2(Align A) { return A.ShiftValue; }
+
+/// Returns the alignment that satisfies both alignments.
+/// Same semantic as MinAlign.
+inline Align commonAlignment(Align A, uint64_t Offset) {
+  return Align(MinAlign(A.value(), Offset));
+}
+
+/// Returns a representation of the alignment that encodes undefined as 0.
+inline unsigned encode(MaybeAlign A) { return A ? A->ShiftValue + 1 : 0; }
+
+/// Dual operation of the encode function above.
+inline MaybeAlign decodeMaybeAlign(unsigned Value) {
+  if (Value == 0)
+    return MaybeAlign();
+  Align Out;
+  Out.ShiftValue = Value - 1;
+  return Out;
+}
+
+/// Returns a representation of the alignment, the encoded value is positive by
+/// definition.
+inline unsigned encode(Align A) { return encode(MaybeAlign(A)); }
+
+/// Comparisons between Align and scalars. Rhs must be positive.
+inline bool operator==(Align Lhs, uint64_t Rhs) {
+  ALIGN_CHECK_ISPOSITIVE(Rhs);
+  return Lhs.value() == Rhs;
+}
+inline bool operator!=(Align Lhs, uint64_t Rhs) {
+  ALIGN_CHECK_ISPOSITIVE(Rhs);
+  return Lhs.value() != Rhs;
+}
+inline bool operator<=(Align Lhs, uint64_t Rhs) {
+  ALIGN_CHECK_ISPOSITIVE(Rhs);
+  return Lhs.value() <= Rhs;
+}
+inline bool operator>=(Align Lhs, uint64_t Rhs) {
+  ALIGN_CHECK_ISPOSITIVE(Rhs);
+  return Lhs.value() >= Rhs;
+}
+inline bool operator<(Align Lhs, uint64_t Rhs) {
+  ALIGN_CHECK_ISPOSITIVE(Rhs);
+  return Lhs.value() < Rhs;
+}
+inline bool operator>(Align Lhs, uint64_t Rhs) {
+  ALIGN_CHECK_ISPOSITIVE(Rhs);
+  return Lhs.value() > Rhs;
+}
+
+/// Comparisons operators between Align.
+inline bool operator==(Align Lhs, Align Rhs) {
+  return Lhs.ShiftValue == Rhs.ShiftValue;
+}
+inline bool operator!=(Align Lhs, Align Rhs) {
+  return Lhs.ShiftValue != Rhs.ShiftValue;
+}
+inline bool operator<=(Align Lhs, Align Rhs) {
+  return Lhs.ShiftValue <= Rhs.ShiftValue;
+}
+inline bool operator>=(Align Lhs, Align Rhs) {
+  return Lhs.ShiftValue >= Rhs.ShiftValue;
+}
+inline bool operator<(Align Lhs, Align Rhs) {
+  return Lhs.ShiftValue < Rhs.ShiftValue;
+}
+inline bool operator>(Align Lhs, Align Rhs) {
+  return Lhs.ShiftValue > Rhs.ShiftValue;
+}
+
+// Don't allow relational comparisons with MaybeAlign.
+bool operator<=(Align Lhs, MaybeAlign Rhs) = delete;
+bool operator>=(Align Lhs, MaybeAlign Rhs) = delete;
+bool operator<(Align Lhs, MaybeAlign Rhs) = delete;
+bool operator>(Align Lhs, MaybeAlign Rhs) = delete;
+
+bool operator<=(MaybeAlign Lhs, Align Rhs) = delete;
+bool operator>=(MaybeAlign Lhs, Align Rhs) = delete;
+bool operator<(MaybeAlign Lhs, Align Rhs) = delete;
+bool operator>(MaybeAlign Lhs, Align Rhs) = delete;
+
+bool operator<=(MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+bool operator>=(MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+bool operator<(MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+bool operator>(MaybeAlign Lhs, MaybeAlign Rhs) = delete;
+
+#ifndef NDEBUG
+// For usage in LLVM_DEBUG macros.
+inline std::string DebugStr(const Align &A) {
+  return std::to_string(A.value());
+}
+// For usage in LLVM_DEBUG macros.
+inline std::string DebugStr(const MaybeAlign &MA) {
+  if (MA)
+    return std::to_string(MA->value());
+  return "None";
+}
+#endif // NDEBUG
+
+#undef ALIGN_CHECK_ISPOSITIVE
+
+} // namespace llvm
+
+#endif // LLVM_SUPPORT_ALIGNMENT_H_