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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32962 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/StringMap.cpp b/lib/Support/StringMap.cpp
index 3229bfe..6cd3745 100644
--- a/lib/Support/StringMap.cpp
+++ b/lib/Support/StringMap.cpp
@@ -33,8 +33,11 @@
/// HashString - Compute a hash code for the specified string.
///
static unsigned HashString(const char *Start, const char *End) {
+ // Bernstein hash function.
unsigned int Result = 0;
- // Perl hash function.
+ // TODO: investigate whether a modified bernstein hash function performs
+ // better: http://eternallyconfuzzled.com/tuts/hashing.html#existing
+ // X*33+c -> X*33^c
while (Start != End)
Result = Result * 33 + *Start++;
Result = Result + (Result >> 5);