[llvm] [llvm-exegesis] Make duplicate snippet repetitor produce whole snippets (PR #77224)

[Clement Courbet via llvm-commits]

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@@ -31,7 +31,11 @@ class DuplicateSnippetRepetitor : public SnippetRepetitor {
       if (!Instructions.empty()) {
         // Add the whole snippet at least once.
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legrosbuffle wrote:

We no longer need the special case to add the snippet once, because we're now always adding the snippet in an all-or-nothing way.

https://github.com/llvm/llvm-project/pull/77224