tools/llvm-xray/xray-extract.cpp

   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
  26 using namespace llvm;
  27 using namespace llvm::xray;
  28 using namespace llvm::yaml;
  29
  30 // llvm-xray extract
  31 // ----------------------------------------------------------------------------
  32 static cl::SubCommand Extract("extract", "Extract instrumentation maps");
  33 static cl::opt<std::string> ExtractInput(cl::Positional,
  34                                          cl::desc("<input file>"), cl::Required,
  35                                          cl::sub(Extract));
  36 static 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));
  40 static cl::alias ExtractOutput2("o", cl::aliasopt(ExtractOutput),
  41                                 cl::desc("Alias for -output"),
  42                                 cl::sub(Extract));
  43 static cl::opt<bool> ExtractSymbolize("symbolize", cl::value_desc("symbolize"),
  44                                       cl::init(false),
  45                                       cl::desc("symbolize functions"),
  46                                       cl::sub(Extract));
  47 static cl::alias ExtractSymbolize2("s", cl::aliasopt(ExtractSymbolize),
  48                                    cl::desc("alias for -symbolize"),
  49                                    cl::sub(Extract));
  50
  51 namespace {
  52
  53 void exportAsYAML(const InstrumentationMap &Map, raw_ostream &OS,
  54                   FuncIdConversionHelper &FH) {
  55   // First we translate the sleds into the YAMLXRaySledEntry objects in a deque.
  56   std::vector<YAMLXRaySledEntry> YAMLSleds;
  57   auto Sleds = Map.sleds();
  58   YAMLSleds.reserve(std::distance(Sleds.begin(), Sleds.end()));
  59   for (const auto &Sled : Sleds) {
  60     auto FuncId = Map.getFunctionId(Sled.Function);
  61     if (!FuncId)
  62       return;
  63     YAMLSleds.push_back({*FuncId, Sled.Address, Sled.Function, Sled.Kind,
  64                          Sled.AlwaysInstrument,
  65                          ExtractSymbolize ? FH.SymbolOrNumber(*FuncId) : ""});
  66   }
  67   Output Out(OS, nullptr, 0);
  68   Out << YAMLSleds;
  69 }
  70
  71 } // namespace
  72
  73 static CommandRegistration Unused(&Extract, []() -> Error {
  74   auto InstrumentationMapOrError = loadInstrumentationMap(ExtractInput);
  75   if (!InstrumentationMapOrError)
  76     return joinErrors(make_error<StringError>(
  77                           Twine("Cannot extract instrumentation map from '") +
  78                               ExtractInput + "'.",
  79                           std::make_error_code(std::errc::invalid_argument)),
  80                       InstrumentationMapOrError.takeError());
  81
  82   std::error_code EC;
  83   raw_fd_ostream OS(ExtractOutput, EC, sys::fs::OpenFlags::OF_Text);
  84   if (EC)
  85     return make_error<StringError>(
  86         Twine("Cannot open file '") + ExtractOutput + "' for writing.", EC);
  87   const auto &FunctionAddresses =
  88       InstrumentationMapOrError->getFunctionAddresses();
  89   symbolize::LLVMSymbolizer Symbolizer;
  90   llvm::xray::FuncIdConversionHelper FuncIdHelper(ExtractInput, Symbolizer,
  91                                                   FunctionAddresses);
  92   exportAsYAML(*InstrumentationMapOrError, OS, FuncIdHelper);
  93   return Error::success();
  94 });