xref: /netbsd-src/external/apache2/llvm/dist/llvm/include/llvm/Support/ItaniumManglingCanonicalizer.h (revision 82d56013d7b633d116a93943de88e08335357a7c)
1 //===--- ItaniumManglingCanonicalizer.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 //===----------------------------------------------------------------------===//
8 //
9 // This file defines a class for computing equivalence classes of mangled names
10 // given a set of equivalences between name fragments.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_SUPPORT_ITANIUMMANGLINGCANONICALIZER_H
15 #define LLVM_SUPPORT_ITANIUMMANGLINGCANONICALIZER_H
16 
17 #include <cstddef>
18 #include <cstdint>
19 
20 namespace llvm {
21 
22 class StringRef;
23 
24 /// Canonicalizer for mangled names.
25 ///
26 /// This class allows specifying a list of "equivalent" manglings. For example,
27 /// you can specify that Ss is equivalent to
28 ///   NSt3__112basic_stringIcNS_11char_traitsIcEENS_9allocatorIcEEEE
29 /// and then manglings that refer to libstdc++'s 'std::string' will be
30 /// considered equivalent to manglings that are the same except that they refer
31 /// to libc++'s 'std::string'.
32 ///
33 /// This can be used when data (eg, profiling data) is available for a version
34 /// of a program built in a different configuration, with correspondingly
35 /// different manglings.
36 class ItaniumManglingCanonicalizer {
37 public:
38   ItaniumManglingCanonicalizer();
39   ItaniumManglingCanonicalizer(const ItaniumManglingCanonicalizer &) = delete;
40   void operator=(const ItaniumManglingCanonicalizer &) = delete;
41   ~ItaniumManglingCanonicalizer();
42 
43   enum class EquivalenceError {
44     Success,
45 
46     /// Both the equivalent manglings have already been used as components of
47     /// some other mangling we've looked at. It's too late to add this
48     /// equivalence.
49     ManglingAlreadyUsed,
50 
51     /// The first equivalent mangling is invalid.
52     InvalidFirstMangling,
53 
54     /// The second equivalent mangling is invalid.
55     InvalidSecondMangling,
56   };
57 
58   enum class FragmentKind {
59     /// The mangling fragment is a <name> (or a predefined <substitution>).
60     Name,
61     /// The mangling fragment is a <type>.
62     Type,
63     /// The mangling fragment is an <encoding>.
64     Encoding,
65   };
66 
67   /// Add an equivalence between \p First and \p Second. Both manglings must
68   /// live at least as long as the canonicalizer.
69   EquivalenceError addEquivalence(FragmentKind Kind, StringRef First,
70                                   StringRef Second);
71 
72   using Key = uintptr_t;
73 
74   /// Form a canonical key for the specified mangling. They key will be the
75   /// same for all equivalent manglings, and different for any two
76   /// non-equivalent manglings, but is otherwise unspecified.
77   ///
78   /// Returns Key() if (and only if) the mangling is not a valid Itanium C++
79   /// ABI mangling.
80   ///
81   /// The string denoted by Mangling must live as long as the canonicalizer.
82   Key canonicalize(StringRef Mangling);
83 
84   /// Find a canonical key for the specified mangling, if one has already been
85   /// formed. Otherwise returns Key().
86   Key lookup(StringRef Mangling);
87 
88 private:
89   struct Impl;
90   Impl *P;
91 };
92 } // namespace llvm
93 
94 #endif // LLVM_SUPPORT_ITANIUMMANGLINGCANONICALIZER_H
95