add bitcode support


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@36855 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Linker/Linker.cpp b/lib/Linker/Linker.cpp
index d7959b4..bfa3004 100644
--- a/lib/Linker/Linker.cpp
+++ b/lib/Linker/Linker.cpp
@@ -14,11 +14,15 @@
 #include "llvm/Linker.h"
 #include "llvm/Module.h"
 #include "llvm/Bytecode/Reader.h"
+#include "llvm/Bitcode/ReaderWriter.h"
 #include "llvm/Config/config.h"
+#include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Support/Streams.h"
 #include "llvm/Support/Compressor.h"
 using namespace llvm;
 
+static const bool Bitcode = false;
+
 Linker::Linker(const std::string& progname, const std::string& modname, unsigned flags)
   : Composite(0)
   , LibPaths()
@@ -100,9 +104,21 @@
 std::auto_ptr<Module>
 Linker::LoadObject(const sys::Path &FN) {
   std::string ParseErrorMessage;
-  Module *Result = ParseBytecodeFile(FN.toString(), 
-                                     Compressor::decompressToNewBuffer,
-                                     &ParseErrorMessage);
+  Module *Result = 0;
+  
+  const std::string &FNS = FN.toString();
+  if (Bitcode) {
+    std::auto_ptr<MemoryBuffer> Buffer(
+                          MemoryBuffer::getFileOrSTDIN(&FNS[0], FNS.size()));
+    if (Buffer.get())
+      Result = ParseBitcodeFile(Buffer.get(), &ParseErrorMessage);
+    else
+      ParseErrorMessage = "Error reading file '" + FNS + "'";
+    
+  } else {
+    Result = ParseBytecodeFile(FNS, Compressor::decompressToNewBuffer,
+                               &ParseErrorMessage);
+  }
   if (Result)
     return std::auto_ptr<Module>(Result);
   Error = "Bytecode file '" + FN.toString() + "' could not be loaded";
@@ -137,6 +153,8 @@
     return FullPath;
   if (FullPath.isBytecodeFile())    // .so file containing bytecode?
     return FullPath;
+  if (FullPath.isBitcodeFile())    // .so file containing bitcode?
+    return FullPath;
 
   // Not found .. fall through