[GitHub] [incubator-brpc] pexeer commented on a change in pull request #1009: bugfix to the hash function HashInts32.

[GitBox <gi...@apache.org>]

pexeer commented on a change in pull request #1009: bugfix to the hash function HashInts32.
URL: https://github.com/apache/incubator-brpc/pull/1009#discussion_r364665770
 
 

 ##########
 File path: src/butil/containers/hash_tables.h
 ##########
 @@ -129,8 +129,10 @@ using BUTIL_HASH_NAMESPACE::hash_set;
 //
 // Contact danakj@chromium.org for any questions.
 inline std::size_t HashInts32(uint32_t value1, uint32_t value2) {
-  uint64_t value1_64 = value1;
-  uint64_t hash64 = (value1_64 << 32) | value2;
+  uint64_t short_random1 = 842304669U;
+  uint64_t short_random2 = 619063811U;
+
+  uint64_t hash64 =  short_random1 * value1 + short_random2 * value2;
 
 Review comment:
   good idea!

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