bolt/tools/bat-dump/bat-dump.cpp

   1 //===- bolt/tools/bat-dump/bat-dump.cpp - BAT dumper utility --------------===//
   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 #include "bolt/Profile/BoltAddressTranslation.h"
  10 #include "llvm/ADT/ArrayRef.h"
  11 #include "llvm/ADT/SmallString.h"
  12 #include "llvm/ADT/StringRef.h"
  13 #include "llvm/ADT/Twine.h"
  14 #include "llvm/Object/Binary.h"
  15 #include "llvm/Object/ELFObjectFile.h"
  16 #include "llvm/Object/Error.h"
  17 #include "llvm/Object/ObjectFile.h"
  18 #include "llvm/Object/SymbolicFile.h"
  19 #include "llvm/Support/Casting.h"
  20 #include "llvm/Support/CommandLine.h"
  21 #include "llvm/Support/Errc.h"
  22 #include "llvm/Support/Error.h"
  23 #include "llvm/Support/ErrorHandling.h"
  24 #include "llvm/Support/ErrorOr.h"
  25 #include "llvm/Support/FileSystem.h"
  26 #include "llvm/Support/Program.h"
  27 #include "llvm/Support/raw_ostream.h"
  28 #include <assert.h>
  29 #include <cstdint>
  30 #include <map>
  31 #include <stdlib.h>
  32 #include <string>
  33 #include <system_error>
  34 #include <type_traits>
  35 #include <utility>
  36
  37 using namespace llvm;
  38 using namespace bolt;
  39
  40 namespace opts {
  41
  42 cl::OptionCategory BatDumpCategory("BAT dump options");
  43
  44 static cl::OptionCategory *BatDumpCategories[] = {&BatDumpCategory};
  45
  46 static cl::opt<std::string> InputFilename(cl::Positional,
  47                                           cl::desc("<executable>"),
  48                                           cl::Required,
  49                                           cl::cat(BatDumpCategory));
  50
  51 static cl::list<uint64_t> Translate("translate",
  52                                     cl::desc("translate addresses using BAT"),
  53                                     cl::value_desc("addr"),
  54                                     cl::cat(BatDumpCategory));
  55
  56 static cl::opt<bool> DumpAll("dump-all", cl::desc("dump all BAT tables"),
  57                              cl::cat(BatDumpCategory));
  58
  59 } // namespace opts
  60
  61 static StringRef ToolName;
  62
  63 static void report_error(StringRef Message, std::error_code EC) {
  64   assert(EC);
  65   errs() << ToolName << ": '" << Message << "': " << EC.message() << ".\n";
  66   exit(1);
  67 }
  68
  69 static void report_error(StringRef Message, Error E) {
  70   assert(E);
  71   errs() << ToolName << ": '" << Message << "': " << toString(std::move(E))
  72          << ".\n";
  73   exit(1);
  74 }
  75
  76 static std::string GetExecutablePath(const char *Argv0) {
  77   SmallString<256> ExecutablePath(Argv0);
  78   // Do a PATH lookup if Argv0 isn't a valid path.
  79   if (!llvm::sys::fs::exists(ExecutablePath))
  80     if (llvm::ErrorOr<std::string> P =
  81             llvm::sys::findProgramByName(ExecutablePath))
  82       ExecutablePath = *P;
  83   return std::string(ExecutablePath);
  84 }
  85
  86 void dumpBATFor(llvm::object::ELFObjectFileBase *InputFile) {
  87   BoltAddressTranslation BAT;
  88   if (!BAT.enabledFor(InputFile)) {
  89     errs() << "error: no BAT table found.\n";
  90     exit(1);
  91   }
  92
  93   // Look for BAT section
  94   bool Found = false;
  95   StringRef SectionContents;
  96   for (const llvm::object::SectionRef &Section : InputFile->sections()) {
  97     Expected<StringRef> SectionNameOrErr = Section.getName();
  98     if (Error E = SectionNameOrErr.takeError())
  99       continue;
 100
 101     if (SectionNameOrErr.get() != BoltAddressTranslation::SECTION_NAME)
 102       continue;
 103
 104     Found = true;
 105     Expected<StringRef> ContentsOrErr = Section.getContents();
 106     if (Error E = ContentsOrErr.takeError())
 107       continue;
 108     SectionContents = ContentsOrErr.get();
 109   }
 110
 111   if (!Found) {
 112     errs() << "BOLT-ERROR: failed to parse BOLT address translation "
 113               "table. No BAT section found\n";
 114     exit(1);
 115   }
 116
 117   if (std::error_code EC = BAT.parse(outs(), SectionContents)) {
 118     errs() << "BOLT-ERROR: failed to parse BOLT address translation "
 119               "table. Malformed BAT section\n";
 120     exit(1);
 121   }
 122
 123   if (opts::DumpAll)
 124     BAT.dump(outs());
 125
 126   if (!opts::Translate.empty()) {
 127     // Build map of <Address, SymbolName> for InputFile
 128     std::map<uint64_t, StringRef> FunctionsMap;
 129     for (const llvm::object::ELFSymbolRef &Symbol : InputFile->symbols()) {
 130       Expected<StringRef> NameOrError = Symbol.getName();
 131       if (NameOrError.takeError())
 132         continue;
 133       if (cantFail(Symbol.getType()) != llvm::object::SymbolRef::ST_Function)
 134         continue;
 135       const StringRef Name = *NameOrError;
 136       const uint64_t Address = cantFail(Symbol.getAddress());
 137       FunctionsMap[Address] = Name;
 138     }
 139
 140     outs() << "Translating addresses according to parsed BAT tables:\n";
 141     for (uint64_t Address : opts::Translate) {
 142       auto FI = FunctionsMap.upper_bound(Address);
 143       if (FI == FunctionsMap.begin()) {
 144         outs() << "No function symbol found for 0x" << Twine::utohexstr(Address)
 145                << "\n";
 146         continue;
 147       }
 148       --FI;
 149       outs() << "0x" << Twine::utohexstr(Address) << " -> " << FI->second
 150              << " + 0x"
 151              << Twine::utohexstr(
 152                     BAT.translate(FI->first, Address - FI->first, false))
 153              << "\n";
 154     }
 155   }
 156 }
 157
 158 int main(int argc, char **argv) {
 159   cl::HideUnrelatedOptions(ArrayRef(opts::BatDumpCategories));
 160   cl::ParseCommandLineOptions(argc, argv, "");
 161
 162   if (!sys::fs::exists(opts::InputFilename))
 163     report_error(opts::InputFilename, errc::no_such_file_or_directory);
 164
 165   ToolName = argv[0];
 166   std::string ToolPath = GetExecutablePath(argv[0]);
 167   Expected<llvm::object::OwningBinary<llvm::object::Binary>> BinaryOrErr =
 168       llvm::object::createBinary(opts::InputFilename);
 169   if (Error E = BinaryOrErr.takeError())
 170     report_error(opts::InputFilename, std::move(E));
 171   llvm::object::Binary &Binary = *BinaryOrErr.get().getBinary();
 172
 173   if (auto *InputFile = dyn_cast<llvm::object::ELFObjectFileBase>(&Binary))
 174     dumpBATFor(InputFile);
 175   else
 176     report_error(opts::InputFilename,
 177                  llvm::object::object_error::invalid_file_type);
 178
 179   return EXIT_SUCCESS;
 180 }