[Lldb-commits] [lldb] r326081 - [Support] Replace HashString with djbHash.

[Jonas Devlieghere via lldb-commits]

Author: jdevlieghere
Date: Mon Feb 26 03:30:13 2018
New Revision: 326081

URL: http://llvm.org/viewvc/llvm-project?rev=326081&view=rev
Log:
[Support] Replace HashString with djbHash.

This removes the HashString function from StringExtraces and replaces
its uses with calls to djbHash from DJB.h

This is *almost* NFC. While the algorithm is identical, the djbHash
implementation in StringExtras used 0 as its seed while the
implementation in DJB uses 5381. The latter has been shown to result in
less collisions and improved avalanching.

https://reviews.llvm.org/D43615
(cherry picked from commit 77f7f965bc9499a9ae768a296ca5a1f7347d1d2c)

Modified:
    lldb/trunk/source/Utility/ConstString.cpp

Modified: lldb/trunk/source/Utility/ConstString.cpp
URL: http://llvm.org/viewvc/llvm-project/lldb/trunk/source/Utility/ConstString.cpp?rev=326081&r1=326080&r2=326081&view=diff
==============================================================================
--- lldb/trunk/source/Utility/ConstString.cpp (original)
+++ lldb/trunk/source/Utility/ConstString.cpp Mon Feb 26 03:30:13 2018
@@ -11,10 +11,10 @@
 
 #include "lldb/Utility/Stream.h"
 
-#include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/iterator.h"            // for iterator_facade_base
 #include "llvm/Support/Allocator.h"       // for BumpPtrAllocator
+#include "llvm/Support/DJB.h"             // for djbHash
 #include "llvm/Support/FormatProviders.h" // for format_provider
 #include "llvm/Support/RWMutex.h"
 #include "llvm/Support/Threading.h"
@@ -171,7 +171,7 @@ public:
 
 protected:
   uint8_t hash(const llvm::StringRef &s) const {
-    uint32_t h = llvm::HashString(s);
+    uint32_t h = llvm::djbHash(s);
     return ((h >> 24) ^ (h >> 16) ^ (h >> 8) ^ h) & 0xff;
   }