[PATCH] D39562: [CodeGen][ObjC] Fix an assertion failure caused by copy elision

[John McCall via Phabricator via cfe-commits]

rjmccall added inline comments.


================
Comment at: include/clang/AST/Expr.h:875
+  /// is set to true.
+  bool IsUnique = false;
+
----------------
Humor me and pack this in the bitfields in Stmt, please. :)


================
Comment at: include/clang/AST/Expr.h:932
 
+  void setIsUnique() { IsUnique = true; }
+  bool isUnique() const { return IsUnique; }
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Can we assert that there's a source expression?


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Comment at: lib/Sema/SemaPseudoObject.cpp:432
+  if (capturedRHS->getType()->getAsCXXRecordDecl() && capturedRHS->isRValue())
+    capturedRHS->setIsUnique();
+
----------------
I think you can unconditionally set this here, actually.  You just need to teach the other two exhaustive emitters in IRGen (scalar and complex) to look through unique OVEs.  Plenty of other things in IRGen could benefit from being able to peephole through unique OVEs.

Also, you can set it on the OVE for the base expression if this is a simple assignment or load.


https://reviews.llvm.org/D39562