[llvm] [DirectX] Add `only-section` to `llvm-objcopy` for `DXContainer` (PR #156372)

[Justin Bogner via llvm-commits]

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@@ -28,6 +28,13 @@ static Error handleArgs(const CommonConfig &Config, Object &Obj) {
       return Config.ToRemove.matches(P.Name);
     };
 
+  if (!Config.OnlySection.empty())
+    RemovePred = [&Config](const Part &P) {
+      // Explicitly keep these sections regardless of previous removes and
+      // remove everything else.
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bogner wrote:

Can/should we error if both `--remove-section` and `--only-section` are specified together?

https://github.com/llvm/llvm-project/pull/156372