[PATCH] D137601: Only hash the start of keys in StringMap

[Jamie Hill-Daniel via Phabricator via llvm-commits]

clubby789 added inline comments.


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Comment at: llvm/lib/Support/StringMap.cpp:87
     init(16);
-  unsigned FullHashValue = djbHash(Name, 0);
+  unsigned FullHashValue = djbHash(Name.take_front(1024), 0);
   unsigned BucketNo = FullHashValue & (NumBuckets - 1);
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1024 was chosen arbitrarily and different numbers may give a better tradeoff between collisions and hash time.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D137601/new/

https://reviews.llvm.org/D137601