LLVM  13.0.0git
SymbolRemappingReader.h
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1 //===- SymbolRemappingReader.h - Read symbol remapping file -----*- 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 contains definitions needed for reading and applying symbol
10 // remapping files.
11 //
12 // Support is provided only for the Itanium C++ name mangling scheme for now.
13 //
14 // NOTE: If you are making changes to this file format, please remember
15 // to document them in the Clang documentation at
16 // tools/clang/docs/UsersManual.rst.
17 //
18 // File format
19 // -----------
20 //
21 // The symbol remappings are written as an ASCII text file. Blank lines and
22 // lines starting with a # are ignored. All other lines specify a kind of
23 // mangled name fragment, along with two fragments of that kind that should
24 // be treated as equivalent, separated by spaces.
25 //
26 // See http://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangling for a
27 // description of the Itanium name mangling scheme.
28 //
29 // The accepted fragment kinds are:
30 //
31 // * name A <name>, such as 6foobar or St3__1
32 // * type A <type>, such as Ss or N4llvm9StringRefE
33 // * encoding An <encoding> (a complete mangling without the leading _Z)
34 //
35 // For example:
36 //
37 // # Ignore int / long differences to treat symbols from 32-bit and 64-bit
38 // # builds with differing size_t / ptrdiff_t / intptr_t as equivalent.
39 // type i l
40 // type j m
41 //
42 // # Ignore differences between libc++ and libstdc++, and between libstdc++'s
43 // # C++98 and C++11 ABIs.
44 // name 3std St3__1
45 // name 3std St7__cxx11
46 //
47 // # Remap a function overload to a specialization of a template (including
48 // # any local symbols declared within it).
49 // encoding N2NS1fEi N2NS1fIiEEvT_
50 //
51 // # Substitutions must be remapped separately from namespace 'std' for now.
52 // name Sa NSt3__19allocatorE
53 // name Sb NSt3__112basic_stringE
54 // type Ss NSt3__112basic_stringIcSt11char_traitsIcESaE
55 // # ...
56 //
57 //===----------------------------------------------------------------------===//
58 
59 #ifndef LLVM_SUPPORT_SYMBOLREMAPPINGREADER_H
60 #define LLVM_SUPPORT_SYMBOLREMAPPINGREADER_H
61 
62 #include "llvm/ADT/StringRef.h"
63 #include "llvm/Support/Error.h"
66 
67 namespace llvm {
68 
69 class SymbolRemappingParseError : public ErrorInfo<SymbolRemappingParseError> {
70 public:
71  SymbolRemappingParseError(StringRef File, int64_t Line, const Twine &Message)
72  : File(File), Line(Line), Message(Message.str()) {}
73 
74  void log(llvm::raw_ostream &OS) const override {
75  OS << File << ':' << Line << ": " << Message;
76  }
77  std::error_code convertToErrorCode() const override {
79  }
80 
81  StringRef getFileName() const { return File; }
82  int64_t getLineNum() const { return Line; }
83  StringRef getMessage() const { return Message; }
84 
85  static char ID;
86 
87 private:
88  std::string File;
89  int64_t Line;
90  std::string Message;
91 };
92 
93 /// Reader for symbol remapping files.
94 ///
95 /// Remaps the symbol names in profile data to match those in the program
96 /// according to a set of rules specified in a given file.
98 public:
99  /// Read remappings from the given buffer, which must live as long as
100  /// the remapper.
102 
103  /// A Key represents an equivalence class of symbol names.
104  using Key = uintptr_t;
105 
106  /// Construct a key for the given symbol, or return an existing one if an
107  /// equivalent name has already been inserted. The symbol name must live
108  /// as long as the remapper.
109  ///
110  /// The result will be Key() if the name cannot be remapped (typically
111  /// because it is not a valid mangled name).
112  Key insert(StringRef FunctionName) {
113  return Canonicalizer.canonicalize(FunctionName);
114  }
115 
116  /// Map the given symbol name into the key for the corresponding equivalence
117  /// class.
118  ///
119  /// The result will typically be Key() if no equivalent symbol has been
120  /// inserted, but this is not guaranteed: a Key different from all keys ever
121  /// returned by \c insert may be returned instead.
122  Key lookup(StringRef FunctionName) {
123  return Canonicalizer.lookup(FunctionName);
124  }
125 
126 private:
127  ItaniumManglingCanonicalizer Canonicalizer;
128 };
129 
130 } // end namespace llvm
131 
132 #endif // LLVM_SUPPORT_SYMBOLREMAPPINGREADER_H
MemoryBuffer.h
llvm
Definition: AllocatorList.h:23
StringRef.h
llvm::ItaniumManglingCanonicalizer
Canonicalizer for mangled names.
Definition: ItaniumManglingCanonicalizer.h:36
Error.h
llvm::SymbolRemappingParseError::getMessage
StringRef getMessage() const
Definition: SymbolRemappingReader.h:83
llvm::SymbolRemappingReader::lookup
Key lookup(StringRef FunctionName)
Map the given symbol name into the key for the corresponding equivalence class.
Definition: SymbolRemappingReader.h:122
llvm::MemoryBuffer
This interface provides simple read-only access to a block of memory, and provides simple methods for...
Definition: MemoryBuffer.h:50
llvm::SymbolRemappingParseError::SymbolRemappingParseError
SymbolRemappingParseError(StringRef File, int64_t Line, const Twine &Message)
Definition: SymbolRemappingReader.h:71
llvm::SymbolRemappingReader::insert
Key insert(StringRef FunctionName)
Construct a key for the given symbol, or return an existing one if an equivalent name has already bee...
Definition: SymbolRemappingReader.h:112
llvm::SymbolRemappingReader
Reader for symbol remapping files.
Definition: SymbolRemappingReader.h:97
llvm::SymbolRemappingParseError::getLineNum
int64_t getLineNum() const
Definition: SymbolRemappingReader.h:82
llvm::SymbolRemappingReader::read
Error read(MemoryBuffer &B)
Read remappings from the given buffer, which must live as long as the remapper.
Definition: SymbolRemappingReader.cpp:27
ItaniumManglingCanonicalizer.h
B
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
llvm::raw_ostream
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:50
llvm::SymbolRemappingParseError::getFileName
StringRef getFileName() const
Definition: SymbolRemappingReader.h:81
llvm::SymbolRemappingParseError::ID
static char ID
Definition: SymbolRemappingReader.h:85
llvm::SymbolRemappingReader::Key
uintptr_t Key
A Key represents an equivalence class of symbol names.
Definition: SymbolRemappingReader.h:104
llvm::ErrorInfo
Base class for user error types.
Definition: Error.h:350
llvm::StringRef
StringRef - Represent a constant reference to a string, i.e.
Definition: StringRef.h:58
llvm::Twine
Twine - A lightweight data structure for efficiently representing the concatenation of temporary valu...
Definition: Twine.h:80
llvm::inconvertibleErrorCode
std::error_code inconvertibleErrorCode()
The value returned by this function can be returned from convertToErrorCode for Error values where no...
Definition: Error.cpp:77
llvm::SymbolRemappingParseError::convertToErrorCode
std::error_code convertToErrorCode() const override
Convert this error to a std::error_code.
Definition: SymbolRemappingReader.h:77
llvm::Error
Lightweight error class with error context and mandatory checking.
Definition: Error.h:157
llvm::SymbolRemappingParseError::log
void log(llvm::raw_ostream &OS) const override
Print an error message to an output stream.
Definition: SymbolRemappingReader.h:74
llvm::ItaniumManglingCanonicalizer::canonicalize
Key canonicalize(StringRef Mangling)
Form a canonical key for the specified mangling.
Definition: ItaniumManglingCanonicalizer.cpp:315
llvm::SymbolRemappingParseError
Definition: SymbolRemappingReader.h:69
llvm::ItaniumManglingCanonicalizer::lookup
Key lookup(StringRef Mangling)
Find a canonical key for the specified mangling, if one has already been formed.
Definition: ItaniumManglingCanonicalizer.cpp:320