[llvm] [InstrProf] Support conditional counter updates (PR #102542)

[via llvm-commits]

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@@ -132,6 +132,11 @@ cl::opt<bool> AtomicFirstCounter(
              "the entry counter)"),
     cl::init(false));
 
+cl::opt<bool> ConditionalCounterUpdate(
+    "conditional-counter-update",
+    cl::desc("Do conditional counter updates in single byte counters mode)"),
+    cl::init(false));
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gulfemsavrun wrote:

I did not enable it by default in case there are any cases where this might not beneficial, and @ellishg raised a good point why we should not make it by default because of the original motivation of single byte counters in PGO.

https://github.com/llvm/llvm-project/pull/102542