[llvm] [LLVM][SLSR] Add a debug counter (PR #119981)

[via llvm-commits]

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@@ -690,7 +694,8 @@ bool StraightLineStrengthReduce::runOnFunction(Function &F) {
   while (!Candidates.empty()) {
     const Candidate &C = Candidates.back();
     if (C.Basis != nullptr) {
-      rewriteCandidateWithBasis(C, *C.Basis);
+      if (DebugCounter::shouldExecute(StraightLineStrengthReduceCounter))
+        rewriteCandidateWithBasis(C, *C.Basis);
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GrumpyPigSkin wrote:

Good point, I have moved it to the top of `rewriteCandidateWithBasis` :)

https://github.com/llvm/llvm-project/pull/119981