Output ELF files after ThinLTO is run.

Summary:
The gold linker allowed you to output the ELF files after LTO was run. It did
it by using the 'obj-path' option. This replicates that behavior.

Reviewers: espindola, ruiu, MaskRay, pcc

Reviewed By: MaskRay, pcc

Subscribers: grimar, emaste, inglorion, arichardson, steven_wu, dexonsmith, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D56046

llvm-svn: 354917
diff --git a/lld/ELF/LTO.cpp b/lld/ELF/LTO.cpp
index 6eecb79..e0011f7 100644
--- a/lld/ELF/LTO.cpp
+++ b/lld/ELF/LTO.cpp
@@ -276,20 +276,23 @@
   if (!Config->ThinLTOCacheDir.empty())
     pruneCache(Config->ThinLTOCacheDir, Config->ThinLTOCachePolicy);
 
-  std::vector<InputFile *> Ret;
-  for (unsigned I = 0; I != MaxTasks; ++I) {
-    if (Buf[I].empty())
-      continue;
-    if (Config->SaveTemps) {
-      if (I == 0)
-        saveBuffer(Buf[I], Config->OutputFile + ".lto.o");
-      else
-        saveBuffer(Buf[I], Config->OutputFile + Twine(I) + ".lto.o");
-    }
-    InputFile *Obj = createObjectFile(MemoryBufferRef(Buf[I], "lto.tmp"));
-    Ret.push_back(Obj);
+  if (!Config->LTOObjPath.empty()) {
+    saveBuffer(Buf[0], Config->LTOObjPath);
+    for (unsigned I = 1; I != MaxTasks; ++I)
+      saveBuffer(Buf[I], Config->LTOObjPath + Twine(I));
   }
 
+  if (Config->SaveTemps) {
+    saveBuffer(Buf[0], Config->OutputFile + ".lto.o");
+    for (unsigned I = 1; I != MaxTasks; ++I)
+      saveBuffer(Buf[I], Config->OutputFile + Twine(I) + ".lto.o");
+  }
+
+  std::vector<InputFile *> Ret;
+  for (unsigned I = 0; I != MaxTasks; ++I)
+    if (!Buf[I].empty())
+      Ret.push_back(createObjectFile(MemoryBufferRef(Buf[I], "lto.tmp")));
+
   for (std::unique_ptr<MemoryBuffer> &File : Files)
     if (File)
       Ret.push_back(createObjectFile(*File));