[clang] [Clang][UBSan] Use EmitCheckedLValue for C++ trivial operator= operands (PR #203737)

[Tony Varghese via cfe-commits]

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@@ -277,22 +277,27 @@ RValue CodeGenFunction::EmitCXXMemberOrOperatorMemberCallExpr(
     }
   }
 
-  LValue This;
-  if (IsArrow) {
-    LValueBaseInfo BaseInfo;
-    TBAAAccessInfo TBAAInfo;
-    Address ThisValue = EmitPointerWithAlignment(Base, &BaseInfo, &TBAAInfo);
-    This = MakeAddrLValue(ThisValue, Base->getType()->getPointeeType(),
-                          BaseInfo, TBAAInfo);
-  } else {
-    This = EmitLValue(Base);
-  }
+  auto getLValueForThis = [this, IsArrow,
+                           Base](bool EmitCheckedForStore = false) {
+    // FIXME: Respect EmitCheckedForStore for the IsArrow case.
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tonykuttai wrote:

Maybe we can add a test to capture its current behaviour.

https://github.com/llvm/llvm-project/pull/203737