[llvm] [HLSL] Fix Root signature test error (PR #127261)

[via llvm-commits]

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@@ -155,6 +155,7 @@ analyzeModule(Module &M) {
 
     if (RootElementListNode == nullptr) {
       reportError(Ctx, "Missing Root Element List Metadata node.");
+      continue;
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joaosaffran wrote:

There was a test for this at some point in time, might get lost during one of the iterations from the original PR. Will make a new one with this fix, a test and I will double-check the current tests.

https://github.com/llvm/llvm-project/pull/127261