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Diffstat (limited to 'externals/demangle/llvm/Demangle/Utility.h')
-rw-r--r-- | externals/demangle/llvm/Demangle/Utility.h | 192 |
1 files changed, 192 insertions, 0 deletions
diff --git a/externals/demangle/llvm/Demangle/Utility.h b/externals/demangle/llvm/Demangle/Utility.h new file mode 100644 index 000000000..50d05c6b1 --- /dev/null +++ b/externals/demangle/llvm/Demangle/Utility.h @@ -0,0 +1,192 @@ +//===--- Utility.h ----------------------------------------------*- 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-FileCopyrightText: Part of the LLVM Project +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// Provide some utility classes for use in the demangler(s). +// +//===----------------------------------------------------------------------===// + +#ifndef DEMANGLE_UTILITY_H +#define DEMANGLE_UTILITY_H + +#include "StringView.h" +#include <cstdint> +#include <cstdlib> +#include <cstring> +#include <iterator> +#include <limits> + +DEMANGLE_NAMESPACE_BEGIN + +// Stream that AST nodes write their string representation into after the AST +// has been parsed. +class OutputStream { + char *Buffer; + size_t CurrentPosition; + size_t BufferCapacity; + + // Ensure there is at least n more positions in buffer. + void grow(size_t N) { + if (N + CurrentPosition >= BufferCapacity) { + BufferCapacity *= 2; + if (BufferCapacity < N + CurrentPosition) + BufferCapacity = N + CurrentPosition; + Buffer = static_cast<char *>(std::realloc(Buffer, BufferCapacity)); + if (Buffer == nullptr) + std::terminate(); + } + } + + void writeUnsigned(uint64_t N, bool isNeg = false) { + // Handle special case... + if (N == 0) { + *this << '0'; + return; + } + + char Temp[21]; + char *TempPtr = std::end(Temp); + + while (N) { + *--TempPtr = '0' + char(N % 10); + N /= 10; + } + + // Add negative sign... + if (isNeg) + *--TempPtr = '-'; + this->operator<<(StringView(TempPtr, std::end(Temp))); + } + +public: + OutputStream(char *StartBuf, size_t Size) + : Buffer(StartBuf), CurrentPosition(0), BufferCapacity(Size) {} + OutputStream() = default; + void reset(char *Buffer_, size_t BufferCapacity_) { + CurrentPosition = 0; + Buffer = Buffer_; + BufferCapacity = BufferCapacity_; + } + + /// If a ParameterPackExpansion (or similar type) is encountered, the offset + /// into the pack that we're currently printing. + unsigned CurrentPackIndex = std::numeric_limits<unsigned>::max(); + unsigned CurrentPackMax = std::numeric_limits<unsigned>::max(); + + OutputStream &operator+=(StringView R) { + size_t Size = R.size(); + if (Size == 0) + return *this; + grow(Size); + std::memmove(Buffer + CurrentPosition, R.begin(), Size); + CurrentPosition += Size; + return *this; + } + + OutputStream &operator+=(char C) { + grow(1); + Buffer[CurrentPosition++] = C; + return *this; + } + + OutputStream &operator<<(StringView R) { return (*this += R); } + + OutputStream &operator<<(char C) { return (*this += C); } + + OutputStream &operator<<(long long N) { + if (N < 0) + writeUnsigned(static_cast<unsigned long long>(-N), true); + else + writeUnsigned(static_cast<unsigned long long>(N)); + return *this; + } + + OutputStream &operator<<(unsigned long long N) { + writeUnsigned(N, false); + return *this; + } + + OutputStream &operator<<(long N) { + return this->operator<<(static_cast<long long>(N)); + } + + OutputStream &operator<<(unsigned long N) { + return this->operator<<(static_cast<unsigned long long>(N)); + } + + OutputStream &operator<<(int N) { + return this->operator<<(static_cast<long long>(N)); + } + + OutputStream &operator<<(unsigned int N) { + return this->operator<<(static_cast<unsigned long long>(N)); + } + + size_t getCurrentPosition() const { return CurrentPosition; } + void setCurrentPosition(size_t NewPos) { CurrentPosition = NewPos; } + + char back() const { + return CurrentPosition ? Buffer[CurrentPosition - 1] : '\0'; + } + + bool empty() const { return CurrentPosition == 0; } + + char *getBuffer() { return Buffer; } + char *getBufferEnd() { return Buffer + CurrentPosition - 1; } + size_t getBufferCapacity() { return BufferCapacity; } +}; + +template <class T> class SwapAndRestore { + T &Restore; + T OriginalValue; + bool ShouldRestore = true; + +public: + SwapAndRestore(T &Restore_) : SwapAndRestore(Restore_, Restore_) {} + + SwapAndRestore(T &Restore_, T NewVal) + : Restore(Restore_), OriginalValue(Restore) { + Restore = std::move(NewVal); + } + ~SwapAndRestore() { + if (ShouldRestore) + Restore = std::move(OriginalValue); + } + + void shouldRestore(bool ShouldRestore_) { ShouldRestore = ShouldRestore_; } + + void restoreNow(bool Force) { + if (!Force && !ShouldRestore) + return; + + Restore = std::move(OriginalValue); + ShouldRestore = false; + } + + SwapAndRestore(const SwapAndRestore &) = delete; + SwapAndRestore &operator=(const SwapAndRestore &) = delete; +}; + +inline bool initializeOutputStream(char *Buf, size_t *N, OutputStream &S, + size_t InitSize) { + size_t BufferSize; + if (Buf == nullptr) { + Buf = static_cast<char *>(std::malloc(InitSize)); + if (Buf == nullptr) + return false; + BufferSize = InitSize; + } else + BufferSize = *N; + + S.reset(Buf, BufferSize); + return true; +} + +DEMANGLE_NAMESPACE_END + +#endif |