--- a/src/share/vm/opto/library_call.cpp	Mon Sep 14 09:49:54 2009 -0700
+++ b/src/share/vm/opto/library_call.cpp	Mon Sep 14 12:14:20 2009 -0700
@@ -133,6 +133,7 @@
     return generate_method_call(method_id, true, false);
   }
 
+  Node* make_string_method_node(int opcode, Node* str1, Node* cnt1, Node* str2, Node* cnt2);
   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);
@@ -796,6 +797,64 @@
 }
 
 
+//------------------------------make_string_method_node------------------------
+// Helper method for String intrinsic finctions.
+Node* LibraryCallKit::make_string_method_node(int opcode, Node* str1, Node* cnt1, Node* str2, Node* cnt2) {
+  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();
+
+  Node* no_ctrl = NULL;
+
+  ciInstanceKlass* klass = env()->String_klass();
+  const TypeInstPtr* string_type =
+        TypeInstPtr::make(TypePtr::BotPTR, klass, false, NULL, 0);
+
+  const TypeAryPtr* value_type =
+        TypeAryPtr::make(TypePtr::NotNull,
+                         TypeAry::make(TypeInt::CHAR,TypeInt::POS),
+                         ciTypeArrayKlass::make(T_CHAR), true, 0);
+
+  // Get start addr of string and substring
+  Node* str1_valuea  = basic_plus_adr(str1, str1, value_offset);
+  Node* str1_value   = make_load(no_ctrl, str1_valuea, value_type, T_OBJECT, string_type->add_offset(value_offset));
+  Node* str1_offseta = basic_plus_adr(str1, str1, offset_offset);
+  Node* str1_offset  = make_load(no_ctrl, str1_offseta, TypeInt::INT, T_INT, string_type->add_offset(offset_offset));
+  Node* str1_start   = array_element_address(str1_value, str1_offset, T_CHAR);
+
+  // Pin loads from String::equals() argument since it could be NULL.
+  Node* str2_ctrl = (opcode == Op_StrEquals) ? control() : no_ctrl;
+  Node* str2_valuea  = basic_plus_adr(str2, str2, value_offset);
+  Node* str2_value   = make_load(str2_ctrl, str2_valuea, value_type, T_OBJECT, string_type->add_offset(value_offset));
+  Node* str2_offseta = basic_plus_adr(str2, str2, offset_offset);
+  Node* str2_offset  = make_load(str2_ctrl, str2_offseta, TypeInt::INT, T_INT, string_type->add_offset(offset_offset));
+  Node* str2_start   = array_element_address(str2_value, str2_offset, T_CHAR);
+
+  Node* result = NULL;
+  switch (opcode) {
+  case Op_StrIndexOf:
+    result = new (C, 6) StrIndexOfNode(control(), memory(TypeAryPtr::CHARS),
+                                       str1_start, cnt1, str2_start, cnt2);
+    break;
+  case Op_StrComp:
+    result = new (C, 6) StrCompNode(control(), memory(TypeAryPtr::CHARS),
+                                    str1_start, cnt1, str2_start, cnt2);
+    break;
+  case Op_StrEquals:
+    result = new (C, 5) StrEqualsNode(control(), memory(TypeAryPtr::CHARS),
+                                      str1_start, str2_start, cnt1);
+    break;
+  default:
+    ShouldNotReachHere();
+    return NULL;
+  }
+
+  // All these intrinsics have checks.
+  C->set_has_split_ifs(true); // Has chance for split-if optimization
+
+  return _gvn.transform(result);
+}
+
 //------------------------------inline_string_compareTo------------------------
 bool LibraryCallKit::inline_string_compareTo() {
 
@@ -824,16 +883,16 @@
   ciInstanceKlass* klass = env()->String_klass();
   const TypeInstPtr* string_type =
     TypeInstPtr::make(TypePtr::BotPTR, klass, false, NULL, 0);
-
-  Node* compare =
-    _gvn.transform(new (C, 7) StrCompNode(
-                        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));
+  Node* no_ctrl = NULL;
+
+  // Get counts for string and argument
+  Node* receiver_cnta = basic_plus_adr(receiver, receiver, count_offset);
+  Node* receiver_cnt  = make_load(no_ctrl, receiver_cnta, TypeInt::INT, T_INT, string_type->add_offset(count_offset));
+
+  Node* argument_cnta = basic_plus_adr(argument, argument, count_offset);
+  Node* argument_cnt  = make_load(no_ctrl, argument_cnta, TypeInt::INT, T_INT, string_type->add_offset(count_offset));
+
+  Node* compare = make_string_method_node(Op_StrComp, receiver, receiver_cnt, argument, argument_cnt);
   push(compare);
   return true;
 }
@@ -865,45 +924,71 @@
     return true;
   }
 
+  // paths (plus control) merge
+  RegionNode* region = new (C, 5) RegionNode(5);
+  Node* phi = new (C, 5) PhiNode(region, TypeInt::BOOL);
+
+  // does source == target string?
+  Node* cmp = _gvn.transform(new (C, 3) CmpPNode(receiver, argument));
+  Node* bol = _gvn.transform(new (C, 2) BoolNode(cmp, BoolTest::eq));
+
+  Node* if_eq = generate_slow_guard(bol, NULL);
+  if (if_eq != NULL) {
+    // receiver == argument
+    phi->init_req(2, intcon(1));
+    region->init_req(2, if_eq);
+  }
+
   // 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);
+  if (!stopped()) {
+    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::ne));
+
+    Node* inst_false = generate_guard(bol, NULL, PROB_MIN);
+    //instanceOf == true, fallthrough
+
+    if (inst_false != NULL) {
+      phi->init_req(3, intcon(0));
+      region->init_req(3, inst_false);
+    }
+  }
 
   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);
+  Node* no_ctrl = NULL;
+  Node* receiver_cnt;
+  Node* argument_cnt;
+
+  if (!stopped()) {
+    // Get counts for string and argument
+    Node* receiver_cnta = basic_plus_adr(receiver, receiver, count_offset);
+    receiver_cnt  = make_load(no_ctrl, receiver_cnta, TypeInt::INT, T_INT, string_type->add_offset(count_offset));
+
+    // Pin load from argument string since it could be NULL.
+    Node* argument_cnta = basic_plus_adr(argument, argument, count_offset);
+    argument_cnt  = make_load(control(), argument_cnta, TypeInt::INT, T_INT, string_type->add_offset(count_offset));
+
+    // Check for receiver count != argument count
+    Node* cmp = _gvn.transform( new(C, 3) CmpINode(receiver_cnt, argument_cnt) );
+    Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::ne) );
+    Node* if_ne = generate_slow_guard(bol, NULL);
+    if (if_ne != NULL) {
+      phi->init_req(4, intcon(0));
+      region->init_req(4, if_ne);
+    }
+  }
+
+  // Check for count == 0 is done by mach node StrEquals.
+
+  if (!stopped()) {
+    Node* equals = make_string_method_node(Op_StrEquals, receiver, receiver_cnt, argument, argument_cnt);
+    phi->init_req(1, equals);
+    region->init_req(1, control());
+  }
 
   // post merge
   set_control(_gvn.transform(region));
@@ -924,10 +1009,8 @@
   Node *argument1 = pop();
 
   Node* equals =
-    _gvn.transform(new (C, 3) AryEqNode(control(),
-                                        argument1,
-                                        argument2)
-                   );
+    _gvn.transform(new (C, 4) AryEqNode(control(), memory(TypeAryPtr::CHARS),
+                                        argument1, argument2) );
   push(equals);
   return true;
 }
@@ -1108,19 +1191,40 @@
       return true;
     }
 
+    // Make the merge point
+    RegionNode* result_rgn = new (C, 3) RegionNode(3);
+    Node*       result_phi = new (C, 3) PhiNode(result_rgn, TypeInt::INT);
+    Node* no_ctrl  = NULL;
+
     ciInstanceKlass* klass = env()->String_klass();
     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));
+    // Get counts for string and substr
+    Node* source_cnta = basic_plus_adr(receiver, receiver, count_offset);
+    Node* source_cnt  = make_load(no_ctrl, source_cnta, TypeInt::INT, T_INT, string_type->add_offset(count_offset));
+
+    Node* substr_cnta = basic_plus_adr(argument, argument, count_offset);
+    Node* substr_cnt  = make_load(no_ctrl, substr_cnta, TypeInt::INT, T_INT, string_type->add_offset(count_offset));
+
+    // Check for substr count > string count
+    Node* cmp = _gvn.transform( new(C, 3) CmpINode(substr_cnt, source_cnt) );
+    Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::gt) );
+    Node* if_gt = generate_slow_guard(bol, NULL);
+    if (if_gt != NULL) {
+      result_phi->init_req(2, intcon(-1));
+      result_rgn->init_req(2, if_gt);
+    }
+
+    if (!stopped()) {
+      result = make_string_method_node(Op_StrIndexOf, receiver, source_cnt, argument, substr_cnt);
+      result_phi->init_req(1, result);
+      result_rgn->init_req(1, control());
+    }
+    set_control(_gvn.transform(result_rgn));
+    record_for_igvn(result_rgn);
+    result = _gvn.transform(result_phi);
+
   } else { //Use LibraryCallKit::string_indexOf
     // don't intrinsify is argument isn't a constant string.
     if (!argument->is_Con()) {