[llvm] [ctxprof] Scale up everything under a root by its `TotalRootEntryCount` (PR #136015)

[Mircea Trofin via llvm-commits]

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@@ -44,11 +44,13 @@
 ; PIPELINE-LABEL: loop:
 ; PIPELINE:         br i1 %cond, label %loop, label %exit, !prof ![[LOOP_BW_ORIG:[0-9]+]]
 
-; PIPELINE: ![[ENTRYPOINT_COUNT]] = !{!"function_entry_count", i64 10}
+; NOTE! all values are multiplied by the TotalRootEntryCount, which is 24
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mtrofin wrote:

not very frequently used from what I can see. Also not used elsewhere in these tests. IIUC it's for commenting a line where you have a legit directive. (https://llvm.org/docs/CommandGuide/FileCheck.html#the-com-directive)

I can further avoid nuances here by not capitalizing "note"

https://github.com/llvm/llvm-project/pull/136015