[clang] [clang] Replace uses of CreatePointerBitCastOrAddrSpaceCast (NFC) (PR #68277)

[Nikita Popov via cfe-commits]

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@@ -2138,6 +2138,8 @@ class IRBuilderBase {
     return Insert(CastInst::CreatePointerCast(V, DestTy), Name);
   }
 
+  // With opaque pointers enabled, this is same as CreateAddressSpaceCast.
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nikic wrote:

All the IRBuilder cast methods are no-ops if old type == new type.

https://github.com/llvm/llvm-project/pull/68277