[PATCH] D97350: [SampleFDO] Another fix to prevent repeated indirect call promotion in sample loader pass

[Hongtao Yu via Phabricator via llvm-commits]

hoy added inline comments.


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Comment at: llvm/lib/Transforms/IPO/SampleProfile.cpp:769
+    if (Pair.first->second != NOMORE_ICP_MAGICNUM &&
+        Data.Count == NOMORE_ICP_MAGICNUM) {
+      OldSum -= Pair.first->second;
----------------
IIUC, `Data` is from profile, why can it be -1?


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Comment at: llvm/lib/Transforms/IPO/SampleProfile.cpp:762
+               Data.Count != NOMORE_ICP_MAGICNUM) {
+      Sum -= Data.Count;
+    } else if (Pair.first->second != NOMORE_ICP_MAGICNUM &&
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wmi wrote:
> davidxl wrote:
> > can it become negative?
> It won't. Sum is got by adding up the counts of all the targets so it should never be less than Data.Count. I add an assertion for it. 
Looks like `Sum` could be zero in one of the callsites of `updateIDTMetaData` where no value is passed and the default value 0 is used.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D97350/new/

https://reviews.llvm.org/D97350