[llvm] [SimplifyCFG] Fix uint32_t overflow in cbranch to cbranch merge prevention check. (PR #72329)

[Arthur Eubanks via llvm-commits]

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@@ -4351,10 +4351,10 @@ static bool SimplifyCondBranchToCondBranch(BranchInst *PBI, BranchInst *BI,
   SmallVector<uint32_t, 2> PredWeights;
   if (!PBI->getMetadata(LLVMContext::MD_unpredictable) &&
       extractBranchWeights(*PBI, PredWeights) &&
-      (PredWeights[0] + PredWeights[1]) != 0) {
+      ((uint64_t)PredWeights[0] + PredWeights[1]) != 0) {
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aeubanks wrote:

`static_cast` is clearer

https://github.com/llvm/llvm-project/pull/72329