//===- SymbolRemappingReader.h - Read symbol remapping file -----*- 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-License-Identifier: Apache-2.0 WITH LLVM-exception
 
//
 
//===----------------------------------------------------------------------===//
 
//
 
// This file contains definitions needed for reading and applying symbol
 
// remapping files.
 
//
 
// Support is provided only for the Itanium C++ name mangling scheme for now.
 
//
 
// NOTE: If you are making changes to this file format, please remember
 
//       to document them in the Clang documentation at
 
//       tools/clang/docs/UsersManual.rst.
 
//
 
// File format
 
// -----------
 
//
 
// The symbol remappings are written as an ASCII text file. Blank lines and
 
// lines starting with a # are ignored. All other lines specify a kind of
 
// mangled name fragment, along with two fragments of that kind that should
 
// be treated as equivalent, separated by spaces.
 
//
 
// See http://itanium-cxx-abi.github.io/cxx-abi/abi.html#mangling for a
 
// description of the Itanium name mangling scheme.
 
//
 
// The accepted fragment kinds are:
 
//
 
//  * name  A <name>, such as 6foobar or St3__1
 
//  * type  A <type>, such as Ss or N4llvm9StringRefE
 
//  * encoding  An <encoding> (a complete mangling without the leading _Z)
 
//
 
// For example:
 
//
 
// # Ignore int / long differences to treat symbols from 32-bit and 64-bit
 
// # builds with differing size_t / ptrdiff_t / intptr_t as equivalent.
 
// type i l
 
// type j m
 
//
 
// # Ignore differences between libc++ and libstdc++, and between libstdc++'s
 
// # C++98 and C++11 ABIs.
 
// name 3std St3__1
 
// name 3std St7__cxx11
 
//
 
// # Remap a function overload to a specialization of a template (including
 
// # any local symbols declared within it).
 
// encoding N2NS1fEi N2NS1fIiEEvT_
 
//
 
// # Substitutions must be remapped separately from namespace 'std' for now.
 
// name Sa NSt3__19allocatorE
 
// name Sb NSt3__112basic_stringE
 
// type Ss NSt3__112basic_stringIcSt11char_traitsIcESaE
 
// # ...
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_SUPPORT_SYMBOLREMAPPINGREADER_H
 
#define LLVM_SUPPORT_SYMBOLREMAPPINGREADER_H
 
 
 
#include "llvm/ADT/StringRef.h"
 
#include "llvm/Support/Error.h"
 
#include "llvm/Support/ItaniumManglingCanonicalizer.h"
 
 
 
namespace llvm {
 
 
 
class MemoryBuffer;
 
 
 
class SymbolRemappingParseError : public ErrorInfo<SymbolRemappingParseError> {
 
public:
 
  SymbolRemappingParseError(StringRef File, int64_t Line, const Twine &Message)
 
      : File(File), Line(Line), Message(Message.str()) {}
 
 
 
  void log(llvm::raw_ostream &OS) const override {
 
    OS << File << ':' << Line << ": " << Message;
 
  }
 
  std::error_code convertToErrorCode() const override {
 
    return llvm::inconvertibleErrorCode();
 
  }
 
 
 
  StringRef getFileName() const { return File; }
 
  int64_t getLineNum() const { return Line; }
 
  StringRef getMessage() const { return Message; }
 
 
 
  static char ID;
 
 
 
private:
 
  std::string File;
 
  int64_t Line;
 
  std::string Message;
 
};
 
 
 
/// Reader for symbol remapping files.
 
///
 
/// Remaps the symbol names in profile data to match those in the program
 
/// according to a set of rules specified in a given file.
 
class SymbolRemappingReader {
 
public:
 
  /// Read remappings from the given buffer, which must live as long as
 
  /// the remapper.
 
  Error read(MemoryBuffer &B);
 
 
 
  /// A Key represents an equivalence class of symbol names.
 
  using Key = uintptr_t;
 
 
 
  /// Construct a key for the given symbol, or return an existing one if an
 
  /// equivalent name has already been inserted. The symbol name must live
 
  /// as long as the remapper.
 
  ///
 
  /// The result will be Key() if the name cannot be remapped (typically
 
  /// because it is not a valid mangled name).
 
  Key insert(StringRef FunctionName) {
 
    return Canonicalizer.canonicalize(FunctionName);
 
  }
 
 
 
  /// Map the given symbol name into the key for the corresponding equivalence
 
  /// class.
 
  ///
 
  /// The result will typically be Key() if no equivalent symbol has been
 
  /// inserted, but this is not guaranteed: a Key different from all keys ever
 
  /// returned by \c insert may be returned instead.
 
  Key lookup(StringRef FunctionName) {
 
    return Canonicalizer.lookup(FunctionName);
 
  }
 
 
 
private:
 
  ItaniumManglingCanonicalizer Canonicalizer;
 
};
 
 
 
} // end namespace llvm
 
 
 
#endif // LLVM_SUPPORT_SYMBOLREMAPPINGREADER_H