Revert "Support for ThinLTO function importing and symbol linking."

This reverts commit r251837, due to a number of bot failures of the form:

/home/grosser/buildslave/perf-x86_64-penryn-O3-polly-fast/llvm.obj/tools/llvm-link/Release+Asserts/llvm-link.o:llvm-link.cpp:function
loadIndex(llvm::LLVMContext&, llvm::Module const*): error: undefined
reference to
'llvm::object::FunctionIndexObjectFile::create(llvm::MemoryBufferRef,
llvm::LLVMContext&, llvm::Module const*, bool)'
/home/grosser/buildslave/perf-x86_64-penryn-O3-polly-fast/llvm.obj/tools/llvm-link/Release+Asserts/llvm-link.o:llvm-link.cpp:function
loadIndex(llvm::LLVMContext&, llvm::Module const*): error: undefined
reference to 'llvm::object::FunctionIndexObjectFile::takeIndex()'

I'm not sure why these are happening - I added Object to the requred
libraries in tools/llvm-link/LLVMBuild.txt and the LLVM_LINK_COMPONENTS
in tools/llvm-link/CMakeLists.txt. Confirmed for my build that these
symbols come out of libLLVMObject.a. What am I missing?

llvm-svn: 251841

3 files changed, 2 insertions, 124 deletions

diff --git a/llvm/tools/llvm-link/CMakeLists.txt b/llvm/tools/llvm-link/CMakeLists.txt
index e4ced186336..d4f5be74904 100644
--- a/llvm/tools/llvm-link/CMakeLists.txt
+++ b/llvm/tools/llvm-link/CMakeLists.txt
@@ -3,7 +3,6 @@ set(LLVM_LINK_COMPONENTS
   Core
   IRReader
   Linker
-  Object
   Support
   )
 
diff --git a/llvm/tools/llvm-link/LLVMBuild.txt b/llvm/tools/llvm-link/LLVMBuild.txt
index 807823820ed..2e386f3c231 100644
--- a/llvm/tools/llvm-link/LLVMBuild.txt
+++ b/llvm/tools/llvm-link/LLVMBuild.txt
@@ -19,4 +19,4 @@
 type = Tool
 name = llvm-link
 parent = Tools
-required_libraries = AsmParser BitReader BitWriter IRReader Linker Object
+required_libraries = AsmParser BitReader BitWriter IRReader Linker
diff --git a/llvm/tools/llvm-link/llvm-link.cpp b/llvm/tools/llvm-link/llvm-link.cpp
index 718d57a343f..7f294f3e719 100644
--- a/llvm/tools/llvm-link/llvm-link.cpp
+++ b/llvm/tools/llvm-link/llvm-link.cpp
@@ -18,12 +18,10 @@
 #include "llvm/IR/AutoUpgrade.h"
 #include "llvm/IR/DiagnosticInfo.h"
 #include "llvm/IR/DiagnosticPrinter.h"
-#include "llvm/IR/FunctionInfo.h"
 #include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Module.h"
 #include "llvm/IR/Verifier.h"
 #include "llvm/IRReader/IRReader.h"
-#include "llvm/Object/FunctionIndexObjectFile.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/ManagedStatic.h"
@@ -45,23 +43,6 @@ static cl::list<std::string> OverridingInputs(
     cl::desc(
         "input bitcode file which can override previously defined symbol(s)"));
 
-// Option to simulate function importing for testing. This enables using
-// llvm-link to simulate ThinLTO backend processes.
-static cl::list<std::string> Imports(
-    "import", cl::ZeroOrMore, cl::value_desc("function:filename"),
-    cl::desc("Pair of function name and filename, where function should be "
-             "imported from bitcode in filename"));
-
-// Option to support testing of function importing. The function index
-// must be specified in the case were we request imports via the -import
-// option, as well as when compiling any module with functions that may be
-// exported (imported by a different llvm-link -import invocation), to ensure
-// consistent promotion and renaming of locals.
-static cl::opt<std::string> FunctionIndex("functionindex",
-                                          cl::desc("Function index filename"),
-                                          cl::init(""),
-                                          cl::value_desc("filename"));
-
 static cl::opt<std::string>
 OutputFilename("o", cl::desc("Override output filename"), cl::init("-"),
                cl::value_desc("filename"));
@@ -137,90 +118,6 @@ static void diagnosticHandler(const DiagnosticInfo &DI) {
   errs() << '\n';
 }
 
-/// Load a function index if requested by the -functionindex option.
-static ErrorOr<std::unique_ptr<FunctionInfoIndex>>
-loadIndex(LLVMContext &Context, const Module *ExportingModule = nullptr) {
-  assert(!FunctionIndex.empty());
-  ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
-      MemoryBuffer::getFileOrSTDIN(FunctionIndex);
-  std::error_code EC = FileOrErr.getError();
-  if (EC)
-    return EC;
-  MemoryBufferRef BufferRef = (FileOrErr.get())->getMemBufferRef();
-  ErrorOr<std::unique_ptr<object::FunctionIndexObjectFile>> ObjOrErr =
-      object::FunctionIndexObjectFile::create(BufferRef, Context,
-                                              ExportingModule);
-  EC = ObjOrErr.getError();
-  if (EC)
-    return EC;
-
-  object::FunctionIndexObjectFile &Obj = **ObjOrErr;
-  return Obj.takeIndex();
-}
-
-/// Import any functions requested via the -import option.
-static bool importFunctions(const char *argv0, LLVMContext &Context,
-                            Linker &L) {
-  for (const auto &Import : Imports) {
-    // Identify the requested function and its bitcode source file.
-    size_t Idx = Import.find(':');
-    if (Idx == std::string::npos) {
-      errs() << "Import parameter bad format: " << Import << "\n";
-      return false;
-    }
-    std::string FunctionName = Import.substr(0, Idx);
-    std::string FileName = Import.substr(Idx + 1, std::string::npos);
-
-    // Load the specified source module.
-    std::unique_ptr<Module> M = loadFile(argv0, FileName, Context);
-    if (!M.get()) {
-      errs() << argv0 << ": error loading file '" << FileName << "'\n";
-      return false;
-    }
-
-    if (verifyModule(*M, &errs())) {
-      errs() << argv0 << ": " << FileName
-             << ": error: input module is broken!\n";
-      return false;
-    }
-
-    Function *F = M->getFunction(FunctionName);
-    if (!F) {
-      errs() << "Ignoring import request for non-existent function "
-             << FunctionName << " from " << FileName << "\n";
-      continue;
-    }
-    // We cannot import weak_any functions without possibly affecting the
-    // order they are seen and selected by the linker, changing program
-    // semantics.
-    if (F->hasWeakAnyLinkage()) {
-      errs() << "Ignoring import request for weak-any function " << FunctionName
-             << " from " << FileName << "\n";
-      continue;
-    }
-
-    if (Verbose)
-      errs() << "Importing " << FunctionName << " from " << FileName << "\n";
-
-    std::unique_ptr<FunctionInfoIndex> Index;
-    if (!FunctionIndex.empty()) {
-      ErrorOr<std::unique_ptr<FunctionInfoIndex>> IndexOrErr =
-          loadIndex(Context);
-      std::error_code EC = IndexOrErr.getError();
-      if (EC) {
-        errs() << EC.message() << '\n';
-        return false;
-      }
-      Index = std::move(IndexOrErr.get());
-    }
-
-    // Link in the specified function.
-    if (L.linkInModule(M.get(), false, Index.get(), F))
-      return false;
-  }
-  return true;
-}
-
 static bool linkFiles(const char *argv0, LLVMContext &Context, Linker &L,
                       const cl::list<std::string> &Files,
                       unsigned Flags) {
@@ -238,24 +135,10 @@ static bool linkFiles(const char *argv0, LLVMContext &Context, Linker &L,
       return false;
     }
 
-    // If a function index is supplied, load it so linkInModule can treat
-    // local functions/variables as exported and promote if necessary.
-    std::unique_ptr<FunctionInfoIndex> Index;
-    if (!FunctionIndex.empty()) {
-      ErrorOr<std::unique_ptr<FunctionInfoIndex>> IndexOrErr =
-          loadIndex(Context, &*M);
-      std::error_code EC = IndexOrErr.getError();
-      if (EC) {
-        errs() << EC.message() << '\n';
-        return false;
-      }
-      Index = std::move(IndexOrErr.get());
-    }
-
     if (Verbose)
       errs() << "Linking in '" << File << "'\n";
 
-    if (L.linkInModule(M.get(), ApplicableFlags, Index.get()))
+    if (L.linkInModule(M.get(), ApplicableFlags))
       return false;
     // All linker flags apply to linking of subsequent files.
     ApplicableFlags = Flags;
@@ -291,10 +174,6 @@ int main(int argc, char **argv) {
                  Flags | Linker::Flags::OverrideFromSrc))
     return 1;
 
-  // Import any functions requested via -import
-  if (!importFunctions(argv[0], Context, L))
-    return 1;
-
   if (DumpAsm) errs() << "Here's the assembly:\n" << *Composite;
 
   std::error_code EC;