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b72788c27a
This adds the `__swift::__runtime` inline namespace to the LLVMSupport interfaces. This avoids an ODR violation when LLVM and Swift are in the same address space. It also will aid in the process of pruning the LLVMSupport library by ensuring that accidental leakage of the llvm namespace does not allow us to remove symbols which we rely on.
58 lines
1.7 KiB
C++
58 lines
1.7 KiB
C++
//===--- AlignOf.h - Portable calculation of type alignment -----*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file defines the AlignedCharArrayUnion class.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_SUPPORT_ALIGNOF_H
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#define LLVM_SUPPORT_ALIGNOF_H
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#include "llvm/Support/Compiler.h"
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#include <cstddef>
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inline namespace __swift { inline namespace __runtime {
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namespace llvm {
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namespace detail {
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template <typename T, typename... Ts> class AlignerImpl {
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T t;
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AlignerImpl<Ts...> rest;
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AlignerImpl() = delete;
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};
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template <typename T> class AlignerImpl<T> {
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T t;
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AlignerImpl() = delete;
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};
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template <typename T, typename... Ts> union SizerImpl {
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char arr[sizeof(T)];
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SizerImpl<Ts...> rest;
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};
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template <typename T> union SizerImpl<T> { char arr[sizeof(T)]; };
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} // end namespace detail
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/// A suitably aligned and sized character array member which can hold elements
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/// of any type.
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///
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/// These types may be arrays, structs, or any other types. This exposes a
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/// `buffer` member which can be used as suitable storage for a placement new of
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/// any of these types.
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template <typename T, typename... Ts> struct AlignedCharArrayUnion {
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alignas(__swift::__runtime::llvm::detail::AlignerImpl<T, Ts...>)
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char buffer[sizeof(llvm::detail::SizerImpl<T, Ts...>)];
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};
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} // end namespace llvm
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}} // namespace swift::runtime
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#endif // LLVM_SUPPORT_ALIGNOF_H
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