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
19using namespace llvm;
20
21char 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.
27Error 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}
81