[llvm] [llvm-dlltool] Remove the i386 underscore prefix from COFFImportFile::ImportName. NFC. (PR #98226)

[Martin Storsjö via llvm-commits]

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@@ -691,10 +692,15 @@ Error writeImportLibrary(StringRef ImportName, StringRef Path,
       }
 
       if (!E.ImportName.empty() && Name != E.ImportName) {
+        StringRef Prefix = "";
+        if (Machine == IMAGE_FILE_MACHINE_I386 && AddUnderscores)
+          Prefix = "_";
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mstorsjo wrote:

FWIW, I traced the addition of the `isDecorated` call to 284ab80f8d055, and it doesn't necessarily seem motivated there. On current git main, we can also remove the call entirely, without affecting any testcase in either `check-llvm` or `check-lld`.

So it seems like the whole call may have been misguided to begin with.

https://github.com/llvm/llvm-project/pull/98226