[llvm] Avoid BlockFrequency overflow problems (PR #66280)

[Matthias Braun via llvm-commits]

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@@ -36,3 +37,10 @@ BlockFrequency BlockFrequency::operator/(BranchProbability Prob) const {
   Freq /= Prob;
   return Freq;
 }
+
+bool BlockFrequency::mul(uint64_t Factor, BlockFrequency *Result) const {
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MatzeB wrote:

Good suggestion!

https://github.com/llvm/llvm-project/pull/66280