[llvm] [BOLT] Add sink block to flow CFG in profile inference (PR #95047)

[via llvm-commits]

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@@ -307,25 +307,32 @@ void BinaryFunction::computeBlockHashes(HashFunction HashFunction) const {
 FlowFunction
 createFlowFunction(const BinaryFunction::BasicBlockOrderType &BlockOrder) {
   FlowFunction Func;
+  std::vector<uint64_t> ExitBlocksIndices;
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WenleiHe wrote:

Again, we have to have a consistent definition of what is an exit block. It doesn't matter where you put it, another flag in `FlowBlock` or extra bookkeeping here. Why do we need to have extra bookkeeping given FlowBlock already has `isExitBlock`.

https://github.com/llvm/llvm-project/pull/95047