Revert "Repress sanitization on User dtor. Modify msan macros for applying attribute"

This reverts commit 5e3bfbb38eb3fb6f568b107f6b239e0aa4c5f334.

llvm-svn: 246450
diff --git a/llvm/lib/IR/Metadata.cpp b/llvm/lib/IR/Metadata.cpp
index 51548a8..7d8c352 100644
--- a/llvm/lib/IR/Metadata.cpp
+++ b/llvm/lib/IR/Metadata.cpp
@@ -401,9 +401,7 @@
   return Ptr;
 }
 
-// Repress memory sanitization, due to use-after-destroy by operator
-// delete. Bug report 24578 identifies this issue.
-LLVM_NO_SANITIZE_MEMORY_ATTRIBUTE void MDNode::operator delete(void *Mem) {
+void MDNode::operator delete(void *Mem) {
   MDNode *N = static_cast<MDNode *>(Mem);
   size_t OpSize = N->NumOperands * sizeof(MDOperand);
   OpSize = RoundUpToAlignment(OpSize, llvm::alignOf<uint64_t>());