Re-apply r174919 - smarter copy/move assignment/construction, with fixes for

bitfield related issues.

The original commit broke Takumi's builder. The bug was caused by bitfield sizes
being determined by their underlying type, rather than the field info. A similar
issue with bitfield alignments showed up on closer testing. Both have been fixed
in this patch.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175389 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 5 insertions, 0 deletions

diff --git a/lib/CodeGen/CodeGenFunction.cpp b/lib/CodeGen/CodeGenFunction.cpp
index cba3316600..dd8906ed3d 100644
--- a/lib/CodeGen/CodeGenFunction.cpp
+++ b/lib/CodeGen/CodeGenFunction.cpp
@@ -560,6 +560,11 @@ void CodeGenFunction::GenerateCode(GlobalDecl GD, llvm::Function *Fn,
     // The lambda "__invoke" function is special, because it forwards or
     // clones the body of the function call operator (but is actually static).
     EmitLambdaStaticInvokeFunction(cast<CXXMethodDecl>(FD));
+  } else if (FD->isDefaulted() && isa<CXXMethodDecl>(FD) &&
+             cast<CXXMethodDecl>(FD)->isCopyAssignmentOperator()) {
+    // Implicit copy-assignment gets the same special treatment as implicit
+    // copy-constructors.
+    emitImplicitAssignmentOperatorBody(Args);
   }
   else
     EmitFunctionBody(Args);