[llvm] [nfc] Common utility macros for `Error` / `Expect<T>` (PR #92150)

[Mircea Trofin via llvm-commits]

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@@ -1420,6 +1420,32 @@ inline Error unwrap(LLVMErrorRef ErrRef) {
       reinterpret_cast<ErrorInfoBase *>(ErrRef)));
 }
 
+/// Common scenarios macros for handling Error or Expect<T> returns
+/// Forward Error.
+#ifndef RETURN_IF_ERROR
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mtrofin wrote:

not too opposed, not sure how pervasive that is - I see stuff like LLVM_VERSION, which makes sense (and other similar cases); this, I'm on the fence. Waiting for others' feedback.

https://github.com/llvm/llvm-project/pull/92150