*** old/src/share/vm/opto/library_call.cpp	Fri Feb  6 14:00:20 2009
--- new/src/share/vm/opto/library_call.cpp	Fri Feb  6 14:00:20 2009

*** 134,143 ****
--- 134,144 ----
    }
  
    bool inline_string_compareTo();
    bool inline_string_indexOf();
    Node* string_indexOf(Node* string_object, ciTypeArray* target_array, jint offset, jint cache_i, jint md2_i);
+   bool inline_string_equals();
    Node* pop_math_arg();
    bool runtime_math(const TypeFunc* call_type, address funcAddr, const char* funcName);
    bool inline_math_native(vmIntrinsics::ID id);
    bool inline_trig(vmIntrinsics::ID id);
    bool inline_trans(vmIntrinsics::ID id);

*** 258,267 ****
--- 259,269 ----
    // -XX:-InlineNatives disables nearly all intrinsics:
    if (!InlineNatives) {
      switch (id) {
      case vmIntrinsics::_indexOf:
      case vmIntrinsics::_compareTo:
+     case vmIntrinsics::_equals:
      case vmIntrinsics::_equalsC:
        break;  // InlineNatives does not control String.compareTo
      default:
        return NULL;
      }

*** 272,281 ****
--- 274,286 ----
      if (!SpecialStringCompareTo)  return NULL;
      break;
    case vmIntrinsics::_indexOf:
      if (!SpecialStringIndexOf)  return NULL;
      break;
+   case vmIntrinsics::_equals:
+     if (!SpecialStringEquals)  return NULL;
+     break;
    case vmIntrinsics::_equalsC:
      if (!SpecialArraysEquals)  return NULL;
      break;
    case vmIntrinsics::_arraycopy:
      if (!InlineArrayCopy)  return NULL;

*** 434,443 ****
--- 439,450 ----
  
    case vmIntrinsics::_compareTo:
      return inline_string_compareTo();
    case vmIntrinsics::_indexOf:
      return inline_string_indexOf();
+   case vmIntrinsics::_equals:
+     return inline_string_equals();
  
    case vmIntrinsics::_getObject:
      return inline_unsafe_access(!is_native_ptr, !is_store, T_OBJECT, false);
    case vmIntrinsics::_getBoolean:
      return inline_unsafe_access(!is_native_ptr, !is_store, T_BOOLEAN, false);

*** 818,827 ****
--- 825,910 ----
                          argument));
    push(compare);
    return true;
  }
  
+ //------------------------------inline_string_equals------------------------
+ bool LibraryCallKit::inline_string_equals() {
+ 
+   if (!Matcher::has_match_rule(Op_StrEquals)) return false;
+ 
+   const int value_offset = java_lang_String::value_offset_in_bytes();
+   const int count_offset = java_lang_String::count_offset_in_bytes();
+   const int offset_offset = java_lang_String::offset_offset_in_bytes();
+ 
+   _sp += 2;
+   Node* argument = pop();  // pop non-receiver first:  it was pushed second
+   Node* receiver = pop();
+  
+   
+   // Null check on self without removing any arguments.  The argument
+   // null check technically happens in the wrong place, which can lead to
+   // invalid stack traces when string compare is inlined into a method
+   // which handles NullPointerExceptions.
+   _sp += 2;
+   receiver = do_null_check(receiver, T_OBJECT);
+   //should not do null check for argument for String.equals(), because spec 
+   //allows to specify NULL as argument. 
+   _sp -= 2;
+   if (stopped()) {
+     return true;
+   }
+ 
+   // get String klass for instanceOf
+   ciInstanceKlass* klass = env()->String_klass();
+ 
+   // two paths (plus control) merge
+   RegionNode* region = new (C, 3) RegionNode(3);
+   Node* phi = new (C, 3) PhiNode(region, TypeInt::BOOL);
+ 
+   Node* inst = gen_instanceof(argument, makecon(TypeKlassPtr::make(klass)));
+   Node* cmp = _gvn.transform(new (C, 3) CmpINode(inst, intcon(1)));
+   Node* bol  = _gvn.transform(new (C, 2) BoolNode(cmp, BoolTest::eq));
+ 
+   IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
+ 
+   Node* if_true  = _gvn.transform(new (C, 1) IfTrueNode(iff));
+   set_control(if_true);
+ 
+   const TypeInstPtr* string_type =
+     TypeInstPtr::make(TypePtr::BotPTR, klass, false, NULL, 0);
+ 
+ // instanceOf == true
+   Node* equals =    
+     _gvn.transform(new (C, 7) StrEqualsNode(
+                         control(),
+                         memory(TypeAryPtr::CHARS),
+                         memory(string_type->add_offset(value_offset)),
+                         memory(string_type->add_offset(count_offset)),
+                         memory(string_type->add_offset(offset_offset)),
+                         receiver,

+                         argument));
+ 
+   phi->init_req(1, _gvn.transform(equals));
+   region->init_req(1, if_true);
+ 
+   //instanceOf == false, fallthrough
+   Node* if_false = _gvn.transform(new (C, 1) IfFalseNode(iff));
+   set_control(if_false);
+ 
+   phi->init_req(2, _gvn.transform(intcon(0)));
+   region->init_req(2, if_false);
+ 
+   // post merge
+   set_control(_gvn.transform(region));
+   record_for_igvn(region);
+ 
+   push(_gvn.transform(phi));
+ 
+   return true;
+ }
+ 
  //------------------------------inline_array_equals----------------------------
  bool LibraryCallKit::inline_array_equals() {
  
    if (!Matcher::has_match_rule(Op_AryEq)) return false;
  

*** 982,992 ****
--- 1065,1074 ----
  #undef __
    C->set_has_loops(true);
    return result;
  }
  
  
  //------------------------------inline_string_indexOf------------------------
  bool LibraryCallKit::inline_string_indexOf() {
  
    _sp += 2;
    Node *argument = pop();  // pop non-receiver first:  it was pushed second

*** 1039,1048 ****
--- 1121,1149 ----
    if (c == 0) {
      push(intcon(0));
      return true;
    }
  
+   Node* result;
+   if (Matcher::has_match_rule(Op_StrIndexOf) &&
+       UseSSE >= 4 && UseSSE42Intrinsics) {
+     // Generate SSE4.2 version of indexOf
+     // We currently only have match rules that use SSE4.2
+     const TypeInstPtr* string_type =
+       TypeInstPtr::make(TypePtr::BotPTR, klass, false, NULL, 0);
+ 
+     result =
+       _gvn.transform(new (C, 7)
+                      StrIndexOfNode(control(),
+                                     memory(TypeAryPtr::CHARS),
+                                     memory(string_type->add_offset(value_offset)),
+                                     memory(string_type->add_offset(count_offset)),
+                                     memory(string_type->add_offset(offset_offset)),
+                                     receiver,
+                                     argument));
+   } else {
+     // Generate default indexOf
      jchar lastChar = pat->char_at(o + (c - 1));
      int cache = 0;
      int i;
      for (i = 0; i < c - 1; i++) {
        assert(i < pat->length(), "out of range");

*** 1055,1065 ****
--- 1156,1167 ----
        if (pat->char_at(o + i) == lastChar) {
          md2 = (c - 1) - i;
        }
      }
  
!   Node* result = string_indexOf(receiver, pat, o, cache, md2);
!     result = string_indexOf(receiver, pat, o, cache, md2);
+   }
    push(result);
    return true;
  }
  
  //--------------------------pop_math_arg--------------------------------