[llvm] 77bc5cc - Fix possible self assign issue for DIEValue

[via llvm-commits]

Author: Wang, Xin10
Date: 2023-05-08T05:55:39-04:00
New Revision: 77bc5cc658a3b57a1fffbcb0490988ce7047d5b9

URL: https://github.com/llvm/llvm-project/commit/77bc5cc658a3b57a1fffbcb0490988ce7047d5b9
DIFF: https://github.com/llvm/llvm-project/commit/77bc5cc658a3b57a1fffbcb0490988ce7047d5b9.diff

LOG: Fix possible self assign issue for DIEValue

In DIEValue's operator assignment constructor, it didn't identify if
the two obj is the same.
I add code to identify them so that it will work correctly when we do
self assign here.

Reviewed By: skan

Differential Revision: https://reviews.llvm.org/D150020

Added: 
    

Modified: 
    llvm/include/llvm/CodeGen/DIE.h

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/CodeGen/DIE.h b/llvm/include/llvm/CodeGen/DIE.h
index a598e0ae0688..c2450f9418bb 100644
--- a/llvm/include/llvm/CodeGen/DIE.h
+++ b/llvm/include/llvm/CodeGen/DIE.h
@@ -464,6 +464,8 @@ class DIEValue {
   }
 
   DIEValue &operator=(const DIEValue &X) {
+    if (this == &X)
+      return *this;
     destroyVal();
     Ty = X.Ty;
     Attribute = X.Attribute;