Revert "Add StringMap::insert(pair) consistent with the standard associative container concept."

This reverts commit r211309.

It looks like it broke some bots:

http://lab.llvm.org:8011/builders/clang-x86_64-ubuntu-gdb-75/builds/15563/steps/compile/logs/stdio

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@211328 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ADT/StringMap.h

@@ -64,7 +64,7 @@ protected:
   }
 
   StringMapImpl(unsigned InitSize, unsigned ItemSize);
-  unsigned RehashTable(unsigned BucketNo = 0);
+  void RehashTable();
 
   /// LookupBucketFor - Look up the bucket that the specified string should end
   /// up in.  If it already exists as a key in the map, the Item pointer for the
@@ -323,28 +323,6 @@ public:
     return true;
   }
 
-  /// insert - Inserts the specified key/value pair into the map if the key
-  /// isn't already in the map. The bool component of the returned pair is true
-  /// if and only if the insertion takes place, and the iterator component of
-  /// the pair points to the element with key equivalent to the key of the pair.
-  std::pair<iterator, bool> insert(std::pair<StringRef, ValueTy> KV) {
-    unsigned BucketNo = LookupBucketFor(KV.first);
-    StringMapEntryBase *&Bucket = TheTable[BucketNo];
-    if (Bucket && Bucket != getTombstoneVal())
-      return std::make_pair(iterator(TheTable + BucketNo, false),
-                            false); // Already exists in map.
-
-    if (Bucket == getTombstoneVal())
-      --NumTombstones;
-    Bucket =
-        MapEntryTy::Create(KV.first, Allocator, std::move(KV.second));
-    ++NumItems;
-    assert(NumItems + NumTombstones <= NumBuckets);
-
-    BucketNo = RehashTable(BucketNo);
-    return std::make_pair(iterator(TheTable + BucketNo, false), true);
-  }
-
   // clear - Empties out the StringMap
   void clear() {
     if (empty()) return;
@@ -368,7 +346,24 @@ public:
   /// return.
   template <typename InitTy>
   MapEntryTy &GetOrCreateValue(StringRef Key, InitTy Val) {
-    return *insert(std::make_pair(Key, std::move(Val))).first;
+    unsigned BucketNo = LookupBucketFor(Key);
+    StringMapEntryBase *&Bucket = TheTable[BucketNo];
+    if (Bucket && Bucket != getTombstoneVal())
+      return *static_cast<MapEntryTy*>(Bucket);
+
+    MapEntryTy *NewItem = MapEntryTy::Create(Key, Allocator, std::move(Val));
+
+    if (Bucket == getTombstoneVal())
+      --NumTombstones;
+    ++NumItems;
+    assert(NumItems + NumTombstones <= NumBuckets);
+
+    // Fill in the bucket for the hash table.  The FullHashValue was already
+    // filled in by LookupBucketFor.
+    Bucket = NewItem;
+
+    RehashTable();
+    return *NewItem;
   }
 
   MapEntryTy &GetOrCreateValue(StringRef Key) {

lib/Support/StringMap.cpp

@@ -181,7 +181,7 @@ StringMapEntryBase *StringMapImpl::RemoveKey(StringRef Key) {
 
 /// RehashTable - Grow the table, redistributing values into the buckets with
 /// the appropriate mod-of-hashtable-size.
-unsigned StringMapImpl::RehashTable(unsigned BucketNo) {
+void StringMapImpl::RehashTable() {
   unsigned NewSize;
   unsigned *HashTable = (unsigned *)(TheTable + NumBuckets + 1);
 
@@ -193,10 +193,9 @@ unsigned StringMapImpl::RehashTable(unsigned BucketNo) {
   } else if (NumBuckets-(NumItems+NumTombstones) <= NumBuckets/8) {
     NewSize = NumBuckets;
   } else {
-    return BucketNo;
+    return;
   }
 
-  unsigned NewBucketNo = BucketNo;
   // Allocate one extra bucket which will always be non-empty.  This allows the
   // iterators to stop at end.
   StringMapEntryBase **NewTableArray =
@@ -216,8 +215,6 @@ unsigned StringMapImpl::RehashTable(unsigned BucketNo) {
       if (!NewTableArray[NewBucket]) {
         NewTableArray[FullHash & (NewSize-1)] = Bucket;
         NewHashArray[FullHash & (NewSize-1)] = FullHash;
-        if (I == BucketNo)
-          NewBucketNo = NewBucket;
         continue;
       }
       
@@ -230,8 +227,6 @@ unsigned StringMapImpl::RehashTable(unsigned BucketNo) {
       // Finally found a slot.  Fill it in.
       NewTableArray[NewBucket] = Bucket;
       NewHashArray[NewBucket] = FullHash;
-      if (I == BucketNo)
-        NewBucketNo = NewBucket;
     }
   }
   
@@ -240,5 +235,4 @@ unsigned StringMapImpl::RehashTable(unsigned BucketNo) {
   TheTable = NewTableArray;
   NumBuckets = NewSize;
   NumTombstones = 0;
-  return NewBucketNo;
 }

unittests/ADT/StringMapTest.cpp

@@ -10,7 +10,6 @@
 #include "gtest/gtest.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/Support/DataTypes.h"
-#include <tuple>
 using namespace llvm;
 
 namespace {
@@ -204,43 +203,6 @@ TEST_F(StringMapTest, InsertTest) {
   assertSingleItemMap();
 }
 
-// Test insert(pair<K, V>) method
-TEST_F(StringMapTest, InsertPairTest) {
-  bool Inserted;
-  StringMap<uint32_t>::iterator NewIt;
-  std::tie(NewIt, Inserted) =
-      testMap.insert(std::make_pair(testKeyFirst, testValue));
-  EXPECT_EQ(1u, testMap.size());
-  EXPECT_EQ(testValue, testMap[testKeyFirst]);
-  EXPECT_EQ(testKeyFirst, NewIt->first());
-  EXPECT_EQ(testValue, NewIt->second);
-  EXPECT_TRUE(Inserted);
-
-  StringMap<uint32_t>::iterator ExistingIt;
-  std::tie(ExistingIt, Inserted) =
-      testMap.insert(std::make_pair(testKeyFirst, testValue + 1));
-  EXPECT_EQ(1u, testMap.size());
-  EXPECT_EQ(testValue, testMap[testKeyFirst]);
-  EXPECT_FALSE(Inserted);
-  EXPECT_EQ(NewIt, ExistingIt);
-}
-
-// Test insert(pair<K, V>) method when rehashing occurs
-TEST_F(StringMapTest, InsertRehashingPairTest) {
-  // Check that the correct iterator is returned when the inserted element is
-  // moved to a different bucket during internal rehashing. This depends on
-  // the particular key, and the implementation of StringMap and HashString.
-  // Changes to those might result in this test not actually checking that.
-  StringMap<uint32_t> t(1);
-  EXPECT_EQ(1u, t.getNumBuckets());
-
-  StringMap<uint32_t>::iterator It =
-    t.insert(std::make_pair("abcdef", 42)).first;
-  EXPECT_EQ(2u, t.getNumBuckets());
-  EXPECT_EQ("abcdef", It->first());
-  EXPECT_EQ(42u, It->second);
-}
-
 // Create a non-default constructable value
 struct StringMapTestStruct {
   StringMapTestStruct(int i) : i(i) {}