vector-based ICs did not update type feedback counts correctly.

src/ia32/code-stubs-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 2215 matching lines @@
   __ bind(&extra_checks_or_miss);
   Label miss;
 
   __ mov(ecx, FieldOperand(ebx, edx, times_half_pointer_size,
                            FixedArray::kHeaderSize));
   __ cmp(ecx, Immediate(TypeFeedbackVector::MegamorphicSentinel(isolate)));
   __ j(equal, &slow_start);
   __ cmp(ecx, Immediate(TypeFeedbackVector::UninitializedSentinel(isolate)));
   __ j(equal, &miss);
 
-  if (!FLAG_trace_ic) {
-    // We are going megamorphic. If the feedback is a JSFunction, it is fine
-    // to handle it here. More complex cases are dealt with in the runtime.
-    __ AssertNotSmi(ecx);
-    __ CmpObjectType(ecx, JS_FUNCTION_TYPE, ecx);
-    __ j(not_equal, &miss);
-    __ mov(FieldOperand(ebx, edx, times_half_pointer_size,
-                        FixedArray::kHeaderSize),
-           Immediate(TypeFeedbackVector::MegamorphicSentinel(isolate)));
-    __ jmp(&slow_start);
-  }
-
   // We are here because tracing is on or we are going monomorphic.
   __ bind(&miss);
   GenerateMiss(masm);
 
   // the slow case
   __ bind(&slow_start);
 
   // Check that the function really is a JavaScript function.
   __ JumpIfSmi(edi, &non_function);
 
@@ skipping 2444 matching lines @@
                               Operand(ebp, 7 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32