[llvm] [coro][pgo] Don't promote pgo counters in the suspend basic block (PR #71263)

[Chuanqi Xu via llvm-commits]

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@@ -242,8 +242,16 @@ class PGOCounterPromoter {
     if (!isPromotionPossible(&L, LoopExitBlocks))
       return;
 
+    auto IsSuspendBB = [&](BasicBlock *BB) {
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ChuanqiXu9 wrote:

In fact, there are other passes failed to handle the suspend intrinsic. Originally we were wondering if we can fix the issues by providing a new analysis pass (e.g., CoroInfoPass). But we failed to go on (due to limited development resources). So it sounds a good idea to extract the common patterns to common utilities. Although I don't think this should be a requirement for this specific PR. 

https://github.com/llvm/llvm-project/pull/71263