Revert [ThinLTO] Fix ThinLTOCodegenerator to export llvm.used symbols

This reverts r357931 (git commit 8b70a5c)

llvm-svn: 357932

Author: cachemeifyoucan

llvm/include/llvm/LTO/LTO.h

@@ -131,7 +131,6 @@ class InputFile {
     using irsymtab::Symbol::isWeak;
     using irsymtab::Symbol::isIndirect;
     using irsymtab::Symbol::getName;
-    using irsymtab::Symbol::getIRName;
     using irsymtab::Symbol::getVisibility;
     using irsymtab::Symbol::canBeOmittedFromSymbolTable;
     using irsymtab::Symbol::isTLS;
@@ -162,9 +161,6 @@ class InputFile {
   // Returns a table with all the comdats used by this file.
   ArrayRef<StringRef> getComdatTable() const { return ComdatTable; }
 
-  // Returns the only BitcodeModule from InputFile.
-  BitcodeModule &getSingleBitcodeModule();
-
 private:
   ArrayRef<Symbol> module_symbols(unsigned I) const {
     const auto &Indices = ModuleSymIndices[I];

llvm/include/llvm/LTO/legacy/ThinLTOCodeGenerator.h

@@ -19,7 +19,6 @@
 #include "llvm/ADT/StringSet.h"
 #include "llvm/ADT/Triple.h"
 #include "llvm/IR/ModuleSummaryIndex.h"
-#include "llvm/LTO/LTO.h"
 #include "llvm/Support/CachePruning.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Support/MemoryBuffer.h"
@@ -32,6 +31,23 @@ class StringRef;
 class LLVMContext;
 class TargetMachine;
 
+/// Wrapper around MemoryBufferRef, owning the identifier
+class ThinLTOBuffer {
+  std::string OwnedIdentifier;
+  StringRef Buffer;
+
+public:
+  ThinLTOBuffer(StringRef Buffer, StringRef Identifier)
+      : OwnedIdentifier(Identifier), Buffer(Buffer) {}
+
+  MemoryBufferRef getMemBuffer() const {
+    return MemoryBufferRef(Buffer,
+                           {OwnedIdentifier.c_str(), OwnedIdentifier.size()});
+  }
+  StringRef getBuffer() const { return Buffer; }
+  StringRef getBufferIdentifier() const { return OwnedIdentifier; }
+};
+
 /// Helper to gather options relevant to the target machine creation
 struct TargetMachineBuilder {
   Triple TheTriple;
@@ -251,36 +267,31 @@ class ThinLTOCodeGenerator {
    * and additionally resolve weak and linkonce symbols.
    * Index is updated to reflect linkage changes from weak resolution.
    */
-  void promote(Module &Module, ModuleSummaryIndex &Index,
-               const lto::InputFile &File);
+  void promote(Module &Module, ModuleSummaryIndex &Index);
 
   /**
    * Compute and emit the imported files for module at \p ModulePath.
    */
   void emitImports(Module &Module, StringRef OutputName,
-                   ModuleSummaryIndex &Index,
-                   const lto::InputFile &File);
+                   ModuleSummaryIndex &Index);
 
   /**
    * Perform cross-module importing for the module identified by
    * ModuleIdentifier.
    */
-  void crossModuleImport(Module &Module, ModuleSummaryIndex &Index,
-                         const lto::InputFile &File);
+  void crossModuleImport(Module &Module, ModuleSummaryIndex &Index);
 
   /**
    * Compute the list of summaries needed for importing into module.
    */
   void gatherImportedSummariesForModule(
       Module &Module, ModuleSummaryIndex &Index,
-      std::map<std::string, GVSummaryMapTy> &ModuleToSummariesForIndex,
-      const lto::InputFile &File);
+      std::map<std::string, GVSummaryMapTy> &ModuleToSummariesForIndex);
 
   /**
    * Perform internalization. Index is updated to reflect linkage changes.
    */
-  void internalize(Module &Module, ModuleSummaryIndex &Index,
-                   const lto::InputFile &File);
+  void internalize(Module &Module, ModuleSummaryIndex &Index);
 
   /**
    * Perform post-importing ThinLTO optimizations.
@@ -302,7 +313,7 @@ class ThinLTOCodeGenerator {
 
   /// Vector holding the input buffers containing the bitcode modules to
   /// process.
-  std::vector<std::unique_ptr<lto::InputFile>> Modules;
+  std::vector<ThinLTOBuffer> Modules;
 
   /// Set of symbols that need to be preserved outside of the set of bitcode
   /// files.

llvm/lib/LTO/LTO.cpp

@@ -420,11 +420,6 @@ StringRef InputFile::getName() const {
   return Mods[0].getModuleIdentifier();
 }
 
-BitcodeModule &InputFile::getSingleBitcodeModule() {
-  assert(Mods.size() == 1 && "Expect only one bitcode module");
-  return Mods[0];
-}
-
 LTO::RegularLTOState::RegularLTOState(unsigned ParallelCodeGenParallelismLevel,
                                       Config &Conf)
     : ParallelCodeGenParallelismLevel(ParallelCodeGenParallelismLevel),