[llvm] Remove the optional bitcast between a musttail call and its ret (PR #201280)

[Matt Arsenault via llvm-commits]

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@@ -7165,6 +7151,21 @@ Error BitcodeReader::materialize(GlobalValue *GV) {
     }
   }
 
+  // Old bitcode allowed an optional bitcast between a musttail call and its
+  // return. Under opaque pointers that cast is always a no-op, and the verifier
+  // no longer accepts it, so drop it.
+  for (Instruction &I : instructions(F)) {
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arsenm wrote:

This should not require a new loop over all instructions 

https://github.com/llvm/llvm-project/pull/201280