1//===- xray-extract.cpp: XRay Instrumentation Map Extraction --------------===//
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// Implementation of the xray-extract.h interface.
10//
11// FIXME: Support other XRay-instrumented binary formats other than ELF.
12//
13//===----------------------------------------------------------------------===//
14
15
16#include "func-id-helper.h"
17#include "xray-registry.h"
18#include "llvm/Object/ObjectFile.h"
19#include "llvm/Support/CommandLine.h"
20#include "llvm/Support/Error.h"
21#include "llvm/Support/FileSystem.h"
22#include "llvm/Support/Format.h"
23#include "llvm/Support/raw_ostream.h"
24#include "llvm/XRay/InstrumentationMap.h"
25
26using namespace llvm;
27using namespace llvm::xray;
28using namespace llvm::yaml;
29
30// llvm-xray extract
31// ----------------------------------------------------------------------------
32static cl::SubCommand Extract("extract", "Extract instrumentation maps");
33static cl::opt<std::string> ExtractInput(cl::Positional,
34                                         cl::desc("<input file>"), cl::Required,
35                                         cl::sub(Extract));
36static cl::opt<std::string>
37    ExtractOutput("output", cl::value_desc("output file"), cl::init("-"),
38                  cl::desc("output file; use '-' for stdout"),
39                  cl::sub(Extract));
40static cl::alias ExtractOutput2("o", cl::aliasopt(ExtractOutput),
41                                cl::desc("Alias for -output"));
42static cl::opt<bool> ExtractSymbolize("symbolize", cl::value_desc("symbolize"),
43                                      cl::init(false),
44                                      cl::desc("symbolize functions"),
45                                      cl::sub(Extract));
46static cl::alias ExtractSymbolize2("s", cl::aliasopt(ExtractSymbolize),
47                                   cl::desc("alias for -symbolize"));
48
49namespace {
50
51void exportAsYAML(const InstrumentationMap &Map, raw_ostream &OS,
52                  FuncIdConversionHelper &FH) {
53  // First we translate the sleds into the YAMLXRaySledEntry objects in a deque.
54  std::vector<YAMLXRaySledEntry> YAMLSleds;
55  auto Sleds = Map.sleds();
56  YAMLSleds.reserve(std::distance(Sleds.begin(), Sleds.end()));
57  for (const auto &Sled : Sleds) {
58    auto FuncId = Map.getFunctionId(Sled.Function);
59    if (!FuncId)
60      return;
61    YAMLSleds.push_back({*FuncId, Sled.Address, Sled.Function, Sled.Kind,
62                         Sled.AlwaysInstrument,
63                         ExtractSymbolize ? FH.SymbolOrNumber(*FuncId) : ""});
64  }
65  Output Out(OS, nullptr, 0);
66  Out << YAMLSleds;
67}
68
69} // namespace
70
71static CommandRegistration Unused(&Extract, []() -> Error {
72  auto InstrumentationMapOrError = loadInstrumentationMap(ExtractInput);
73  if (!InstrumentationMapOrError)
74    return joinErrors(make_error<StringError>(
75                          Twine("Cannot extract instrumentation map from '") +
76                              ExtractInput + "'.",
77                          std::make_error_code(std::errc::invalid_argument)),
78                      InstrumentationMapOrError.takeError());
79
80  std::error_code EC;
81  raw_fd_ostream OS(ExtractOutput, EC, sys::fs::OpenFlags::OF_Text);
82  if (EC)
83    return make_error<StringError>(
84        Twine("Cannot open file '") + ExtractOutput + "' for writing.", EC);
85  const auto &FunctionAddresses =
86      InstrumentationMapOrError->getFunctionAddresses();
87  symbolize::LLVMSymbolizer Symbolizer;
88  llvm::xray::FuncIdConversionHelper FuncIdHelper(ExtractInput, Symbolizer,
89                                                  FunctionAddresses);
90  exportAsYAML(*InstrumentationMapOrError, OS, FuncIdHelper);
91  return Error::success();
92});
93