Introduce extra IC state to record additional feedback from IC-s.

src/x64/stub-cache-x64.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1309 matching lines @@
     __ cmpq(FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset), rax);
     __ j(not_equal, miss);
   } else {
     __ Cmp(rdi, Handle<JSFunction>(function));
     __ j(not_equal, miss);
   }
 }
 
 
 MaybeObject* CallStubCompiler::GenerateMissBranch() {
-  MaybeObject* maybe_obj =
-      StubCache::ComputeCallMiss(arguments().immediate(), kind_);
+  MaybeObject* maybe_obj = StubCache::ComputeCallMiss(arguments().immediate(),
+                                                      kind_);
   Object* obj;
   if (!maybe_obj->ToObject(&obj)) return maybe_obj;
   __ Jump(Handle<Code>(Code::cast(obj)), RelocInfo::CODE_TARGET);
   return obj;
 }
 
 
 MaybeObject* CallStubCompiler::CompileCallField(JSObject* object,
                                                 JSObject* holder,
                                                 int index,
@@ skipping 311 matching lines @@
   //  -- ...
   //  -- rsp[(argc + 1) * 8] : receiver
   // -----------------------------------
 
   // If object is not a string, bail out to regular call.
   if (!object->IsString() || cell != NULL) return Heap::undefined_value();
 
   const int argc = arguments().immediate();
 
   Label miss;
+  Label name_miss;
   Label index_out_of_range;
+  Label* index_out_of_range_label = &index_out_of_range;
 
-  GenerateNameCheck(name, &miss);
+  if (kind_ == Code::CALL_IC && extra_ic_state_ == DEFAULT_STRING_STUB) {
+    index_out_of_range_label = &miss;
+  }
+
+  GenerateNameCheck(name, &name_miss);
 
   // Check that the maps starting from the prototype haven't changed.
   GenerateDirectLoadGlobalFunctionPrototype(masm(),
                                             Context::STRING_FUNCTION_INDEX,
                                             rax,
                                             &miss);
   ASSERT(object != holder);
   CheckPrototypes(JSObject::cast(object->GetPrototype()), rax, holder,
                   rbx, rdx, rdi, name, &miss);
 
   Register receiver = rbx;
   Register index = rdi;
   Register scratch = rdx;
   Register result = rax;
   __ movq(receiver, Operand(rsp, (argc + 1) * kPointerSize));
   if (argc > 0) {
     __ movq(index, Operand(rsp, (argc - 0) * kPointerSize));
   } else {
     __ LoadRoot(index, Heap::kUndefinedValueRootIndex);
   }
 
   StringCharCodeAtGenerator char_code_at_generator(receiver,
                                                    index,
                                                    scratch,
                                                    result,
                                                    &miss,  // When not a string.
                                                    &miss,  // When not a number.
-                                                   &index_out_of_range,
+                                                   index_out_of_range_label,
                                                    STRING_INDEX_IS_NUMBER);
   char_code_at_generator.GenerateFast(masm());
   __ ret((argc + 1) * kPointerSize);
 
   StubRuntimeCallHelper call_helper;
   char_code_at_generator.GenerateSlow(masm(), call_helper);
 
-  __ bind(&index_out_of_range);
-  __ LoadRoot(rax, Heap::kNanValueRootIndex);
-  __ ret((argc + 1) * kPointerSize);
+  if (index_out_of_range.is_linked()) {
+    __ bind(&index_out_of_range);
+    __ LoadRoot(rax, Heap::kNanValueRootIndex);
+    __ ret((argc + 1) * kPointerSize);
+  }
 
   __ bind(&miss);
+  // Restore function name in rcx.
+  __ Move(rcx, Handle<String>(name));
+  __ bind(&name_miss);
   Object* obj;
   { MaybeObject* maybe_obj = GenerateMissBranch();
     if (!maybe_obj->ToObject(&obj)) return maybe_obj;
   }
 
   // Return the generated code.
   return GetCode(function);
 }
 
 
@@ skipping 10 matching lines @@
   //  -- ...
   //  -- rsp[(argc + 1) * 8] : receiver
   // -----------------------------------
 
   // If object is not a string, bail out to regular call.
   if (!object->IsString() || cell != NULL) return Heap::undefined_value();
 
   const int argc = arguments().immediate();
 
   Label miss;
+  Label name_miss;
   Label index_out_of_range;
+  Label* index_out_of_range_label = &index_out_of_range;
 
-  GenerateNameCheck(name, &miss);
+  if (kind_ == Code::CALL_IC && extra_ic_state_ == DEFAULT_STRING_STUB) {
+    index_out_of_range_label = &miss;
+  }
+
+  GenerateNameCheck(name, &name_miss);
 
   // Check that the maps starting from the prototype haven't changed.
   GenerateDirectLoadGlobalFunctionPrototype(masm(),
                                             Context::STRING_FUNCTION_INDEX,
                                             rax,
                                             &miss);
   ASSERT(object != holder);
   CheckPrototypes(JSObject::cast(object->GetPrototype()), rax, holder,
                   rbx, rdx, rdi, name, &miss);
 
   Register receiver = rax;
   Register index = rdi;
   Register scratch1 = rbx;
   Register scratch2 = rdx;
   Register result = rax;
   __ movq(receiver, Operand(rsp, (argc + 1) * kPointerSize));
   if (argc > 0) {
     __ movq(index, Operand(rsp, (argc - 0) * kPointerSize));
   } else {
     __ LoadRoot(index, Heap::kUndefinedValueRootIndex);
   }
 
   StringCharAtGenerator char_at_generator(receiver,
                                           index,
                                           scratch1,
                                           scratch2,
                                           result,
                                           &miss,  // When not a string.
                                           &miss,  // When not a number.
-                                          &index_out_of_range,
+                                          index_out_of_range_label,
                                           STRING_INDEX_IS_NUMBER);
   char_at_generator.GenerateFast(masm());
   __ ret((argc + 1) * kPointerSize);
 
   StubRuntimeCallHelper call_helper;
   char_at_generator.GenerateSlow(masm(), call_helper);
 
-  __ bind(&index_out_of_range);
-  __ LoadRoot(rax, Heap::kEmptyStringRootIndex);
-  __ ret((argc + 1) * kPointerSize);
+  if (index_out_of_range.is_linked()) {
+    __ bind(&index_out_of_range);
+    __ LoadRoot(rax, Heap::kEmptyStringRootIndex);
+    __ ret((argc + 1) * kPointerSize);
+  }
 
   __ bind(&miss);
+  // Restore function name in rcx.
+  __ Move(rcx, Handle<String>(name));
+  __ bind(&name_miss);
   Object* obj;
   { MaybeObject* maybe_obj = GenerateMissBranch();
     if (!maybe_obj->ToObject(&obj)) return maybe_obj;
   }
 
   // Return the generated code.
   return GetCode(function);
 }
 
 
@@ skipping 1322 matching lines @@
   // Return the generated code.
   return GetCode();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64