[PATCH] D120508: introducing profi flags

[Hongtao Yu via Phabricator via llvm-commits]

hoy added inline comments.


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Comment at: llvm/include/llvm/Transforms/Utils/SampleProfileLoaderBaseImpl.h:923
     const BasicBlockT *EntryBB = getEntryBB(&F);
+    ErrorOr<uint64_t> EntryWeight = getBlockWeight(EntryBB);
     if (BlockWeights[EntryBB] > 0) {
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Remove this since it's not used anywhere?


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Comment at: llvm/lib/Transforms/Utils/SampleProfileInference.cpp:744-746
+        std::max(MinCostMaxFlow::MinBaseDistance,
+                 std::min(Func.Blocks[Func.Entry].Flow,
+                          MinCostMaxFlow::AuxCostUnlikely / (NumBlocks() + 1)));
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wenlei wrote:
> Could you explain this a bit more, how does this minimizes total multiplicative Flow increase for the remaining edges?
Same question here. Looks like we are turning the previous subtraction into a division. So it's not a linear reduction anymore. For edges with smaller flow, the cost now will be much larger than previously, which would prevent adding more flow to that edge?


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  https://reviews.llvm.org/D120508/new/

https://reviews.llvm.org/D120508