[llvm] [cmake] Add possibility to use ChooseMSVCCRT.cmake when include LLVM library
[llvm-core.git] / include / llvm / Support / StringSaver.h
blobc54044e3986ca64579d7663beb81e315bd72d864
1 //===- llvm/Support/StringSaver.h -------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
9 #ifndef LLVM_SUPPORT_STRINGSAVER_H
10 #define LLVM_SUPPORT_STRINGSAVER_H
12 #include "llvm/ADT/DenseSet.h"
13 #include "llvm/ADT/StringRef.h"
14 #include "llvm/ADT/Twine.h"
15 #include "llvm/Support/Allocator.h"
17 namespace llvm {
19 /// Saves strings in the provided stable storage and returns a
20 /// StringRef with a stable character pointer.
21 class StringSaver final {
22 BumpPtrAllocator &Alloc;
24 public:
25 StringSaver(BumpPtrAllocator &Alloc) : Alloc(Alloc) {}
27 // All returned strings are null-terminated: *save(S).end() == 0.
28 StringRef save(const char *S) { return save(StringRef(S)); }
29 StringRef save(StringRef S);
30 StringRef save(const Twine &S) { return save(StringRef(S.str())); }
31 StringRef save(const std::string &S) { return save(StringRef(S)); }
34 /// Saves strings in the provided stable storage and returns a StringRef with a
35 /// stable character pointer. Saving the same string yields the same StringRef.
36 ///
37 /// Compared to StringSaver, it does more work but avoids saving the same string
38 /// multiple times.
39 ///
40 /// Compared to StringPool, it performs fewer allocations but doesn't support
41 /// refcounting/deletion.
42 class UniqueStringSaver final {
43 StringSaver Strings;
44 llvm::DenseSet<llvm::StringRef> Unique;
46 public:
47 UniqueStringSaver(BumpPtrAllocator &Alloc) : Strings(Alloc) {}
49 // All returned strings are null-terminated: *save(S).end() == 0.
50 StringRef save(const char *S) { return save(StringRef(S)); }
51 StringRef save(StringRef S);
52 StringRef save(const Twine &S) { return save(StringRef(S.str())); }
53 StringRef save(const std::string &S) { return save(StringRef(S)); }
57 #endif