Replace HashStringUsingDJB with llvm::djbHash

Summary:
The llvm function is equivalent to this one. Where possible I tried to
replace const char* with llvm::StringRef to avoid extra strlen
computations. In most places, I was able to track the c string back to
the ConstString it was created from.

I also create a test that verifies we are able to lookup names with
unicode characters, as a bug in the llvm compiler (it accidentally used
a different hash function) meant this was not working until recently.

This also removes the unused ExportTable class.

Reviewers: aprantl, davide

Subscribers: JDevlieghere, lldb-commits

Differential Revision: https://reviews.llvm.org/D43596

llvm-svn: 325927

1 files changed, 3 insertions, 4 deletions

diff --git a/lldb/source/Target/ObjCLanguageRuntime.cpp b/lldb/source/Target/ObjCLanguageRuntime.cpp
index d3cc7c019dc..e50167dcb58 100644
--- a/lldb/source/Target/ObjCLanguageRuntime.cpp
+++ b/lldb/source/Target/ObjCLanguageRuntime.cpp
@@ -23,6 +23,7 @@
 #include "lldb/Utility/Timer.h"
 
 #include "llvm/ADT/StringRef.h"
+#include "llvm/Support/DJB.h"
 
 using namespace lldb;
 using namespace lldb_private;
@@ -45,8 +46,7 @@ bool ObjCLanguageRuntime::AddClass(ObjCISA isa,
   if (isa != 0) {
     m_isa_to_descriptor[isa] = descriptor_sp;
     // class_name is assumed to be valid
-    m_hash_to_isa_map.insert(
-        std::make_pair(MappedHash::HashStringUsingDJB(class_name), isa));
+    m_hash_to_isa_map.insert(std::make_pair(llvm::djbHash(class_name), isa));
     return true;
   }
   return false;
@@ -180,8 +180,7 @@ ObjCLanguageRuntime::GetDescriptorIterator(const ConstString &name) {
     } else {
       // Name hashes were provided, so use them to efficiently lookup name to
       // isa/descriptor
-      const uint32_t name_hash =
-          MappedHash::HashStringUsingDJB(name.GetCString());
+      const uint32_t name_hash = llvm::djbHash(name.GetStringRef());
       std::pair<HashToISAIterator, HashToISAIterator> range =
           m_hash_to_isa_map.equal_range(name_hash);
       for (HashToISAIterator range_pos = range.first; range_pos != range.second;