[llvm] r213557 - Correct the ownership passing semantics of object::createBinary and make them explicit in the type system.

[David Blaikie]

Author: dblaikie
Date: Mon Jul 21 11:26:24 2014
New Revision: 213557

URL: http://llvm.org/viewvc/llvm-project?rev=213557&view=rev
Log:
Correct the ownership passing semantics of object::createBinary and make them explicit in the type system.

createBinary documented that it destroyed the parameter in error cases,
though by observation it does not. By passing the unique_ptr by value
rather than lvalue reference, callers are now explicit about passing
ownership and the function implements the documented contract. Remove
the explicit documentation, since now the behavior cannot be anything
other than what was documented, so it's redundant.

Also drops a unique_ptr::release in llvm-nm that was always run on a
null unique_ptr anyway.

Modified:
    llvm/trunk/include/llvm/Object/Binary.h
    llvm/trunk/lib/Object/Archive.cpp
    llvm/trunk/lib/Object/Binary.cpp
    llvm/trunk/tools/llvm-nm/llvm-nm.cpp

Modified: llvm/trunk/include/llvm/Object/Binary.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Object/Binary.h?rev=213557&r1=213556&r2=213557&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Object/Binary.h (original)
+++ llvm/trunk/include/llvm/Object/Binary.h Mon Jul 21 11:26:24 2014
@@ -125,10 +125,8 @@ public:
 
 /// @brief Create a Binary from Source, autodetecting the file type.
 ///
-/// @param Source The data to create the Binary from. Ownership is transferred
-///        to the Binary if successful. If an error is returned,
-///        Source is destroyed by createBinary before returning.
-ErrorOr<Binary *> createBinary(std::unique_ptr<MemoryBuffer> &Source,
+/// @param Source The data to create the Binary from.
+ErrorOr<Binary *> createBinary(std::unique_ptr<MemoryBuffer> Source,
                                LLVMContext *Context = nullptr);
 
 ErrorOr<Binary *> createBinary(StringRef Path);

Modified: llvm/trunk/lib/Object/Archive.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/Archive.cpp?rev=213557&r1=213556&r2=213557&view=diff
==============================================================================
--- llvm/trunk/lib/Object/Archive.cpp (original)
+++ llvm/trunk/lib/Object/Archive.cpp Mon Jul 21 11:26:24 2014
@@ -181,7 +181,7 @@ Archive::Child::getAsBinary(LLVMContext
   if (std::error_code EC = BuffOrErr.getError())
     return EC;
 
-  return createBinary(*BuffOrErr, Context);
+  return createBinary(std::move(*BuffOrErr), Context);
 }
 
 ErrorOr<Archive *> Archive::create(std::unique_ptr<MemoryBuffer> Source) {

Modified: llvm/trunk/lib/Object/Binary.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Object/Binary.cpp?rev=213557&r1=213556&r2=213557&view=diff
==============================================================================
--- llvm/trunk/lib/Object/Binary.cpp (original)
+++ llvm/trunk/lib/Object/Binary.cpp Mon Jul 21 11:26:24 2014
@@ -38,7 +38,7 @@ StringRef Binary::getFileName() const {
   return Data->getBufferIdentifier();
 }
 
-ErrorOr<Binary *> object::createBinary(std::unique_ptr<MemoryBuffer> &Buffer,
+ErrorOr<Binary *> object::createBinary(std::unique_ptr<MemoryBuffer> Buffer,
                                        LLVMContext *Context) {
   sys::fs::file_magic Type = sys::fs::identify_magic(Buffer->getBuffer());
 
@@ -79,5 +79,5 @@ ErrorOr<Binary *> object::createBinary(S
       MemoryBuffer::getFileOrSTDIN(Path);
   if (std::error_code EC = FileOrErr.getError())
     return EC;
-  return createBinary(FileOrErr.get());
+  return createBinary(std::move(*FileOrErr));
 }

Modified: llvm/trunk/tools/llvm-nm/llvm-nm.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-nm/llvm-nm.cpp?rev=213557&r1=213556&r2=213557&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-nm/llvm-nm.cpp (original)
+++ llvm/trunk/tools/llvm-nm/llvm-nm.cpp Mon Jul 21 11:26:24 2014
@@ -993,13 +993,12 @@ static void dumpSymbolNamesFromFile(std:
       MemoryBuffer::getFileOrSTDIN(Filename);
   if (error(BufferOrErr.getError(), Filename))
     return;
-  std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
 
   LLVMContext &Context = getGlobalContext();
-  ErrorOr<Binary *> BinaryOrErr = createBinary(Buffer, &Context);
+  ErrorOr<Binary *> BinaryOrErr =
+      createBinary(std::move(*BufferOrErr), &Context);
   if (error(BinaryOrErr.getError(), Filename))
     return;
-  Buffer.release();
   std::unique_ptr<Binary> Bin(BinaryOrErr.get());
 
   if (Archive *A = dyn_cast<Archive>(Bin.get())) {