[msan] Better hash function for chained origins.

llvm-svn: 212440

diff --git a/compiler-rt/lib/msan/msan_chained_origin_depot.cc b/compiler-rt/lib/msan/msan_chained_origin_depot.cc
index a98bcf5..cc7e537 100644 (file)
--- a/compiler-rt/lib/msan/msan_chained_origin_depot.cc
+++ b/compiler-rt/lib/msan/msan_chained_origin_depot.cc
@@ -19,7 +19,7 @@ namespace __msan {
 struct ChainedOriginDepotDesc {
   u32 here_id;
   u32 prev_id;
-  u32 hash() const { return here_id ^ prev_id; }
+  u32 hash() const { return (here_id * 0x1f1f1f1f) ^ prev_id; }
   bool is_valid() { return true; }
 };