From 6159d0fe2d40708b5a3caab91c8292253894ebf3 Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Wed, 2 Feb 2011 19:04:30 +0000
Subject: [PATCH] Revert r124704, which uniqued code-completion strings. The
 space savings of 25% sounds impressive, except that this amounted to only
 about 360k in our standard "large" completion result set (40,000 results).
 Since code completion is performance-sensitive, the 4% slowdown due to
 uniquing outweighs the 360k benefit.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124737 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/clang/Sema/CodeCompleteConsumer.h | 38 -----------------------
 lib/Sema/CodeCompleteConsumer.cpp         | 31 ------------------
 2 files changed, 69 deletions(-)

diff --git a/include/clang/Sema/CodeCompleteConsumer.h b/include/clang/Sema/CodeCompleteConsumer.h
index bd9a868101..8cb8e75393 100644
--- a/include/clang/Sema/CodeCompleteConsumer.h
+++ b/include/clang/Sema/CodeCompleteConsumer.h
@@ -15,9 +15,7 @@
 
 #include "clang/AST/Type.h"
 #include "clang/AST/CanonicalType.h"
-#include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/StringExtras.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/Allocator.h"
 #include "clang-c/Index.h"
@@ -423,47 +421,11 @@ public:
   std::string getAsString() const;   
 };
 
-/// \brief \c DenseMap information object for StringRefs.
-struct DenseMapStringRefInfo {
-  static inline llvm::StringRef getEmptyKey() {
-    return llvm::StringRef(reinterpret_cast<const char*>((intptr_t)-1), 0);
-  }
-  static inline llvm::StringRef getTombstoneKey() {
-    return llvm::StringRef(reinterpret_cast<const char *>((intptr_t)-2), 0);
-  }
-  static unsigned getHashValue(llvm::StringRef Str) {
-    return llvm::HashString(Str);
-  }
-  static bool isEqual(llvm::StringRef LHS, llvm::StringRef RHS) { 
-    if (LHS.size() == 0 && RHS.size() == 0) {
-      intptr_t LHSVal = reinterpret_cast<intptr_t>(LHS.data());
-      intptr_t RHSVal = reinterpret_cast<intptr_t>(RHS.data());
-      if (LHSVal == -1 || LHSVal == -2 || RHSVal == -1 || RHSVal == -2)
-        return LHSVal == RHSVal;
-      
-      return true;
-    }
-    
-    return LHS == RHS;
-  }
-};
-
 /// \brief An allocator used specifically for the purpose of code completion.
 class CodeCompletionAllocator : public llvm::BumpPtrAllocator { 
-  llvm::DenseSet<llvm::StringRef, DenseMapStringRefInfo> UniqueStrings;
-  unsigned StringBytesAllocated;
-  unsigned StringBytesUniqued;
-  unsigned StringsAllocated;
-  unsigned StringsUniqued;
-  
 public:
-  CodeCompletionAllocator();
-  ~CodeCompletionAllocator();
-  
   /// \brief Copy the given string into this allocator.
   const char *CopyString(llvm::StringRef String);
-  
-  void PrintStats();
 };
   
 /// \brief A builder class used to construct new code-completion strings.
diff --git a/lib/Sema/CodeCompleteConsumer.cpp b/lib/Sema/CodeCompleteConsumer.cpp
index 572c8dcbd0..cb2dd234b4 100644
--- a/lib/Sema/CodeCompleteConsumer.cpp
+++ b/lib/Sema/CodeCompleteConsumer.cpp
@@ -220,41 +220,10 @@ const char *CodeCompletionString::getTypedText() const {
   return 0;
 }
 
-CodeCompletionAllocator::CodeCompletionAllocator()
-  : llvm::BumpPtrAllocator(), StringBytesAllocated(0), StringBytesUniqued(0), 
-    StringsAllocated(0), StringsUniqued(0)
-{
-}
-
-CodeCompletionAllocator::~CodeCompletionAllocator() { }
-
-void CodeCompletionAllocator::PrintStats() {
-  llvm::errs() << "---Code completion memory allocation---\n" 
-    << "String bytes uniqued: " << StringBytesUniqued << "/"
-    << StringBytesAllocated << " (" 
-    << ((float)StringBytesUniqued*100/StringBytesAllocated)
-    << ")\nStrings uniqued: " << StringsUniqued << "/" << StringsAllocated
-    << " (" << ((float)StringsUniqued*100/StringsAllocated)
-  << ")\n";
-  
-  llvm::BumpPtrAllocator::PrintStats();
-}
-
 const char *CodeCompletionAllocator::CopyString(llvm::StringRef String) {
-  llvm::DenseSet<llvm::StringRef, DenseMapStringRefInfo>::iterator Uniqued
-    = UniqueStrings.find(String);
-  ++StringsAllocated;
-  StringBytesAllocated += String.size() + 1;
-  if (Uniqued != UniqueStrings.end()) {
-    StringBytesUniqued += String.size() + 1;
-    ++StringsUniqued;
-    return Uniqued->data();
-  }
-  
   char *Mem = (char *)Allocate(String.size() + 1, 1);
   std::copy(String.begin(), String.end(), Mem);
   Mem[String.size()] = 0;
-  UniqueStrings.insert(llvm::StringRef(Mem, String.size()));
   return Mem;
 }
 
-- 
2.40.0