lib/Support/SymbolRemappingReader.cpp

   1 //===- SymbolRemappingReader.cpp - Read symbol remapping file -------------===//
   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 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Support/SymbolRemappingReader.h"
  15 #include "llvm/ADT/StringSwitch.h"
  16 #include "llvm/ADT/Twine.h"
  17 #include "llvm/Support/LineIterator.h"
  18
  19 using namespace llvm;
  20
  21 char SymbolRemappingParseError::ID;
  22
  23 /// Load a set of name remappings from a text file.
  24 ///
  25 /// See the documentation at the top of the file for an explanation of
  26 /// the expected format.
  27 Error SymbolRemappingReader::read(MemoryBuffer &B) {
  28   line_iterator LineIt(B, /*SkipBlanks=*/true, '#');
  29
  30   auto ReportError = [&](Twine Msg) {
  31     return llvm::make_error<SymbolRemappingParseError>(
  32         B.getBufferIdentifier(), LineIt.line_number(), Msg);
  33   };
  34
  35   for (; !LineIt.is_at_eof(); ++LineIt) {
  36     StringRef Line = *LineIt;
  37     Line = Line.ltrim(' ');
  38     // line_iterator only detects comments starting in column 1.
  39     if (Line.startswith("#") || Line.empty())
  40       continue;
  41
  42     SmallVector<StringRef, 4> Parts;
  43     Line.split(Parts, ' ', /*MaxSplits*/-1, /*KeepEmpty*/false);
  44
  45     if (Parts.size() != 3)
  46       return ReportError("Expected 'kind mangled_name mangled_name', "
  47                          "found '" + Line + "'");
  48
  49     using FK = ItaniumManglingCanonicalizer::FragmentKind;
  50     Optional<FK> FragmentKind = StringSwitch<Optional<FK>>(Parts[0])
  51                                     .Case("name", FK::Name)
  52                                     .Case("type", FK::Type)
  53                                     .Case("encoding", FK::Encoding)
  54                                     .Default(None);
  55     if (!FragmentKind)
  56       return ReportError("Invalid kind, expected 'name', 'type', or 'encoding',"
  57                          " found '" + Parts[0] + "'");
  58
  59     using EE = ItaniumManglingCanonicalizer::EquivalenceError;
  60     switch (Canonicalizer.addEquivalence(*FragmentKind, Parts[1], Parts[2])) {
  61     case EE::Success:
  62       break;
  63
  64     case EE::ManglingAlreadyUsed:
  65       return ReportError("Manglings '" + Parts[1] + "' and '" + Parts[2] + "' "
  66                          "have both been used in prior remappings. Move this "
  67                          "remapping earlier in the file.");
  68
  69     case EE::InvalidFirstMangling:
  70       return ReportError("Could not demangle '" + Parts[1] + "' "
  71                          "as a <" + Parts[0] + ">; invalid mangling?");
  72
  73     case EE::InvalidSecondMangling:
  74       return ReportError("Could not demangle '" + Parts[2] + "' "
  75                          "as a <" + Parts[0] + ">; invalid mangling?");
  76     }
  77   }
  78
  79   return Error::success();
  80 }