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-rw-r--r--externals/demangle/llvm/Demangle/StringView.h127
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diff --git a/externals/demangle/llvm/Demangle/StringView.h b/externals/demangle/llvm/Demangle/StringView.h
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+++ b/externals/demangle/llvm/Demangle/StringView.h
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+//===--- StringView.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
+//
+//===----------------------------------------------------------------------===//
+//
+// FIXME: Use std::string_view instead when we support C++17.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef DEMANGLE_STRINGVIEW_H
+#define DEMANGLE_STRINGVIEW_H
+
+#include "DemangleConfig.h"
+#include <algorithm>
+#include <cassert>
+#include <cstring>
+
+DEMANGLE_NAMESPACE_BEGIN
+
+class StringView {
+ const char *First;
+ const char *Last;
+
+public:
+ static const size_t npos = ~size_t(0);
+
+ template <size_t N>
+ StringView(const char (&Str)[N]) : First(Str), Last(Str + N - 1) {}
+ StringView(const char *First_, const char *Last_)
+ : First(First_), Last(Last_) {}
+ StringView(const char *First_, size_t Len)
+ : First(First_), Last(First_ + Len) {}
+ StringView(const char *Str) : First(Str), Last(Str + std::strlen(Str)) {}
+ StringView() : First(nullptr), Last(nullptr) {}
+
+ StringView substr(size_t From) const {
+ return StringView(begin() + From, size() - From);
+ }
+
+ size_t find(char C, size_t From = 0) const {
+ size_t FindBegin = std::min(From, size());
+ // Avoid calling memchr with nullptr.
+ if (FindBegin < size()) {
+ // Just forward to memchr, which is faster than a hand-rolled loop.
+ if (const void *P = ::memchr(First + FindBegin, C, size() - FindBegin))
+ return size_t(static_cast<const char *>(P) - First);
+ }
+ return npos;
+ }
+
+ StringView substr(size_t From, size_t To) const {
+ if (To >= size())
+ To = size() - 1;
+ if (From >= size())
+ From = size() - 1;
+ return StringView(First + From, First + To);
+ }
+
+ StringView dropFront(size_t N = 1) const {
+ if (N >= size())
+ N = size();
+ return StringView(First + N, Last);
+ }
+
+ StringView dropBack(size_t N = 1) const {
+ if (N >= size())
+ N = size();
+ return StringView(First, Last - N);
+ }
+
+ char front() const {
+ assert(!empty());
+ return *begin();
+ }
+
+ char back() const {
+ assert(!empty());
+ return *(end() - 1);
+ }
+
+ char popFront() {
+ assert(!empty());
+ return *First++;
+ }
+
+ bool consumeFront(char C) {
+ if (!startsWith(C))
+ return false;
+ *this = dropFront(1);
+ return true;
+ }
+
+ bool consumeFront(StringView S) {
+ if (!startsWith(S))
+ return false;
+ *this = dropFront(S.size());
+ return true;
+ }
+
+ bool startsWith(char C) const { return !empty() && *begin() == C; }
+
+ bool startsWith(StringView Str) const {
+ if (Str.size() > size())
+ return false;
+ return std::equal(Str.begin(), Str.end(), begin());
+ }
+
+ const char &operator[](size_t Idx) const { return *(begin() + Idx); }
+
+ const char *begin() const { return First; }
+ const char *end() const { return Last; }
+ size_t size() const { return static_cast<size_t>(Last - First); }
+ bool empty() const { return First == Last; }
+};
+
+inline bool operator==(const StringView &LHS, const StringView &RHS) {
+ return LHS.size() == RHS.size() &&
+ std::equal(LHS.begin(), LHS.end(), RHS.begin());
+}
+
+DEMANGLE_NAMESPACE_END
+
+#endif