Introduce a new temporary MDNode concept. Temporary MDNodes are

not part of the IR, are not uniqued, and may be safely RAUW'd.
This replaces a variety of alternate mechanisms for achieving
the same effect.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@111681 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 0 deletions

diff --git a/include/llvm/Metadata.h b/include/llvm/Metadata.h
index ef9646e977..f773817e82 100644
--- a/include/llvm/Metadata.h
+++ b/include/llvm/Metadata.h
@@ -128,6 +128,16 @@ public:
                                        
   static MDNode *getIfExists(LLVMContext &Context, Value *const *Vals,
                              unsigned NumVals);
+
+  /// getTemporary - Return a temporary MDNode, for use in constructing
+  /// cyclic MDNode structures. A temporary MDNode is not uniqued,
+  /// may be RAUW'd, and must be manually deleted with deleteTemporary.
+  static MDNode *getTemporary(LLVMContext &Context, Value *const *Vals,
+                              unsigned NumVals);
+
+  /// deleteTemporary - Deallocate a node created by getTemporary. The
+  /// node must not have any users.
+  static void deleteTemporary(MDNode *N);
   
   /// getOperand - Return specified operand.
   Value *getOperand(unsigned i) const;