[llvm] MTM: fix style after cursory reading (NFC) (PR #100404)

[Michael Maitland via llvm-commits]

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@@ -546,7 +540,7 @@ MachineTraceMetrics::Ensemble::invalidate(const MachineBasicBlock *BadMBB) {
   if (BadTBI.hasValidHeight()) {
     BadTBI.invalidateHeight();
     WorkList.push_back(BadMBB);
-    do {
+    while (!WorkList.empty()) {
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michaelmaitland wrote:

I missed the `WorkList.push_back(BadMBB);`. We know the worklist will never start out empty. So this change is good.

https://github.com/llvm/llvm-project/pull/100404