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

src/ia32/stub-cache-ia32.cc

 // Copyright 2006-2009 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 1343 matching lines @@
     __ cmp(FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset),
            Immediate(Handle<SharedFunctionInfo>(function->shared())));
     __ j(not_equal, miss, not_taken);
   } else {
     __ cmp(Operand(edi), Immediate(Handle<JSFunction>(function)));
     __ j(not_equal, miss, not_taken);
   }
 }
 
 
-MaybeObject* CallStubCompiler::GenerateMissBranch() {
+MaybeObject* CallStubCompiler::GenerateBranchHelper(
+    Code::ExtraICState extra_ic_state) {
+  MaybeObject* maybe_obj = StubCache::ComputeCallMiss(arguments().immediate(),
+                                                      kind_,
+                                                      extra_ic_state);
   Object* obj;
-  { MaybeObject* maybe_obj =
-        StubCache::ComputeCallMiss(arguments().immediate(), kind_);
-    if (!maybe_obj->ToObject(&obj)) return maybe_obj;
-  }
+  if (!maybe_obj->ToObject(&obj)) return maybe_obj;
   __ jmp(Handle<Code>(Code::cast(obj)), RelocInfo::CODE_TARGET);
   return obj;
 }
 
 
 MUST_USE_RESULT MaybeObject* CallStubCompiler::CompileCallField(
     JSObject* object,
     JSObject* holder,
     int index,
     String* name) {
@@ skipping 337 matching lines @@
                                                    &miss,  // When not a number.
                                                    &index_out_of_range,
                                                    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);
-  __ Set(eax, Immediate(Factory::nan_value()));
-  __ ret((argc + 1) * kPointerSize);
+  // Restore function name in ecx.
+  __ Set(ecx, Immediate(Handle<String>(name)));
+  if (kind_ == Code::CALL_IC && extra_ic_state_ == DEFAULT_STRING_STUB) {
+    // Change the extra state to record the fact that we've seen an
+    // out of bounds index.
+    MaybeObject* maybe_obj =
+        GenerateExtraStateChangeBranch(STRING_INDEX_OUT_OF_BOUNDS);
+    if (maybe_obj->IsFailure()) return maybe_obj;
+  } else {
+    __ Set(eax, Immediate(Factory::nan_value()));
+    __ ret((argc + 1) * kPointerSize);
+  }
 
   __ bind(&miss);
   Object* obj;
   { MaybeObject* maybe_obj = GenerateMissBranch();
     if (!maybe_obj->ToObject(&obj)) return maybe_obj;
   }
 
   // Return the generated code.
   return GetCode(function);
 }
@@ skipping 53 matching lines @@
                                           &miss,  // When not a number.
                                           &index_out_of_range,
                                           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);
-  __ Set(eax, Immediate(Factory::empty_string()));
-  __ ret((argc + 1) * kPointerSize);
+  // Restore function name in ecx.
+  __ Set(ecx, Immediate(Handle<String>(name)));
+  if (kind_ == Code::CALL_IC && extra_ic_state_ == DEFAULT_STRING_STUB) {
+    // Change the extra state to record the fact that we've seen an
+    // out of bounds index.
+    MaybeObject* maybe_obj =
+        GenerateExtraStateChangeBranch(STRING_INDEX_OUT_OF_BOUNDS);
+    if (maybe_obj->IsFailure()) return maybe_obj;
+  } else {
+    __ Set(eax, Immediate(Factory::empty_string()));
+    __ ret((argc + 1) * kPointerSize);
+  }
 
   __ bind(&miss);
   Object* obj;
   { MaybeObject* maybe_obj = GenerateMissBranch();
     if (!maybe_obj->ToObject(&obj)) return maybe_obj;
   }
 
   // Return the generated code.
   return GetCode(function);
 }
@@ skipping 1469 matching lines @@
   // Return the generated code.
   return GetCode();
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32