Don't own the buffer in object::Binary.

Owning the buffer is somewhat inflexible. Some Binaries have sub Binaries
(like Archive) and we had to create dummy buffers just to handle that. It is
also a bad fit for IRObjectFile where the Module wants to own the buffer too.

Keeping this ownership would make supporting IR inside native objects
particularly painful.

This patch focuses in lib/Object. If something elsewhere used to own an Binary,
now it also owns a MemoryBuffer.

This patch introduces a few new types.

* MemoryBufferRef. This is just a pair of StringRefs for the data and name.
  This is to MemoryBuffer as StringRef is to std::string.
* OwningBinary. A combination of Binary and a MemoryBuffer. This is needed
  for convenience functions that take a filename and return both the
  buffer and the Binary using that buffer.

The C api now uses OwningBinary to avoid any change in semantics. I will start
a new thread to see if we want to change it and how.

llvm-svn: 216002

1 files changed, 5 insertions, 4 deletions

diff --git a/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
index 65e2aba29ee..9583fb2add6 100644
--- a/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
+++ b/llvm/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -119,7 +119,7 @@ void MCJIT::addObjectFile(std::unique_ptr<object::ObjectFile> Obj) {
   NotifyObjectEmitted(*LoadedObject);
 }
 
-void MCJIT::addArchive(std::unique_ptr<object::Archive> A) {
+void MCJIT::addArchive(object::OwningBinary<object::Archive> A) {
   Archives.push_back(std::move(A));
 }
 
@@ -161,8 +161,8 @@ ObjectBufferStream* MCJIT::emitObject(Module *M) {
   if (ObjCache) {
     // MemoryBuffer is a thin wrapper around the actual memory, so it's OK
     // to create a temporary object here and delete it after the call.
-    std::unique_ptr<MemoryBuffer> MB = CompiledObject->getMemBuffer();
-    ObjCache->notifyObjectCompiled(M, MB.get());
+    MemoryBufferRef MB = CompiledObject->getMemBuffer();
+    ObjCache->notifyObjectCompiled(M, MB);
   }
 
   return CompiledObject.release();
@@ -295,7 +295,8 @@ uint64_t MCJIT::getSymbolAddress(const std::string &Name,
   if (Addr)
     return Addr;
 
-  for (std::unique_ptr<object::Archive> &A : Archives) {
+  for (object::OwningBinary<object::Archive> &OB : Archives) {
+    object::Archive *A = OB.getBinary().get();
     // Look for our symbols in each Archive
     object::Archive::child_iterator ChildIt = A->findSym(Name);
     if (ChildIt != A->child_end()) {