lib/Object/FunctionIndexObjectFile.cpp

   1 //===- FunctionIndexObjectFile.cpp - Function index file implementation ---===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // Part of the FunctionIndexObjectFile class implementation.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Object/FunctionIndexObjectFile.h"
  15 #include "llvm/ADT/STLExtras.h"
  16 #include "llvm/Bitcode/ReaderWriter.h"
  17 #include "llvm/IR/FunctionInfo.h"
  18 #include "llvm/MC/MCStreamer.h"
  19 #include "llvm/Object/ObjectFile.h"
  20 #include "llvm/Support/MemoryBuffer.h"
  21 #include "llvm/Support/raw_ostream.h"
  22 using namespace llvm;
  23 using namespace object;
  24
  25 FunctionIndexObjectFile::FunctionIndexObjectFile(
  26     MemoryBufferRef Object, std::unique_ptr<FunctionInfoIndex> I)
  27     : SymbolicFile(Binary::ID_FunctionIndex, Object), Index(std::move(I)) {}
  28
  29 FunctionIndexObjectFile::~FunctionIndexObjectFile() {}
  30
  31 std::unique_ptr<FunctionInfoIndex> FunctionIndexObjectFile::takeIndex() {
  32   return std::move(Index);
  33 }
  34
  35 ErrorOr<MemoryBufferRef>
  36 FunctionIndexObjectFile::findBitcodeInObject(const ObjectFile &Obj) {
  37   for (const SectionRef &Sec : Obj.sections()) {
  38     StringRef SecName;
  39     if (std::error_code EC = Sec.getName(SecName))
  40       return EC;
  41     if (SecName == ".llvmbc") {
  42       StringRef SecContents;
  43       if (std::error_code EC = Sec.getContents(SecContents))
  44         return EC;
  45       return MemoryBufferRef(SecContents, Obj.getFileName());
  46     }
  47   }
  48
  49   return object_error::bitcode_section_not_found;
  50 }
  51
  52 ErrorOr<MemoryBufferRef>
  53 FunctionIndexObjectFile::findBitcodeInMemBuffer(MemoryBufferRef Object) {
  54   sys::fs::file_magic Type = sys::fs::identify_magic(Object.getBuffer());
  55   switch (Type) {
  56   case sys::fs::file_magic::bitcode:
  57     return Object;
  58   case sys::fs::file_magic::elf_relocatable:
  59   case sys::fs::file_magic::macho_object:
  60   case sys::fs::file_magic::coff_object: {
  61     ErrorOr<std::unique_ptr<ObjectFile>> ObjFile =
  62         ObjectFile::createObjectFile(Object, Type);
  63     if (!ObjFile)
  64       return ObjFile.getError();
  65     return findBitcodeInObject(*ObjFile->get());
  66   }
  67   default:
  68     return object_error::invalid_file_type;
  69   }
  70 }
  71
  72 // Looks for function index in the given memory buffer.
  73 // returns true if found, else false.
  74 bool FunctionIndexObjectFile::hasFunctionSummaryInMemBuffer(
  75     MemoryBufferRef Object, LLVMContext &Context) {
  76   ErrorOr<MemoryBufferRef> BCOrErr = findBitcodeInMemBuffer(Object);
  77   if (!BCOrErr)
  78     return false;
  79
  80   return hasFunctionSummary(BCOrErr.get(), Context, nullptr);
  81 }
  82
  83 // Parse function index in the given memory buffer.
  84 // Return new FunctionIndexObjectFile instance containing parsed
  85 // function summary/index.
  86 ErrorOr<std::unique_ptr<FunctionIndexObjectFile>>
  87 FunctionIndexObjectFile::create(MemoryBufferRef Object, LLVMContext &Context,
  88                                 const Module *ExportingModule, bool IsLazy) {
  89   std::unique_ptr<FunctionInfoIndex> Index;
  90
  91   ErrorOr<MemoryBufferRef> BCOrErr = findBitcodeInMemBuffer(Object);
  92   if (!BCOrErr)
  93     return BCOrErr.getError();
  94
  95   ErrorOr<std::unique_ptr<FunctionInfoIndex>> IOrErr = getFunctionInfoIndex(
  96       BCOrErr.get(), Context, nullptr, ExportingModule, IsLazy);
  97
  98   if (std::error_code EC = IOrErr.getError())
  99     return EC;
 100
 101   Index = std::move(IOrErr.get());
 102
 103   return llvm::make_unique<FunctionIndexObjectFile>(Object, std::move(Index));
 104 }
 105
 106 // Parse the function summary information for function with the
 107 // given name out of the given buffer. Parsed information is
 108 // stored on the index object saved in this object.
 109 std::error_code FunctionIndexObjectFile::findFunctionSummaryInMemBuffer(
 110     MemoryBufferRef Object, LLVMContext &Context, StringRef FunctionName) {
 111   sys::fs::file_magic Type = sys::fs::identify_magic(Object.getBuffer());
 112   switch (Type) {
 113   case sys::fs::file_magic::bitcode: {
 114     return readFunctionSummary(Object, Context, nullptr, FunctionName,
 115                                std::move(Index));
 116   }
 117   default:
 118     return object_error::invalid_file_type;
 119   }
 120 }