Only to the relevant checks in LoadFunctionPrototype

src/ia32/macro-assembler-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/bootstrapper.h"
 #include "src/codegen.h"
@@ skipping 1958 matching lines @@
   j(sign, then_label);
   bind(&ok);
 }
 
 
 void MacroAssembler::TryGetFunctionPrototype(Register function,
                                              Register result,
                                              Register scratch,
                                              Label* miss,
                                              bool miss_on_bound_function) {
-  // Check that the receiver isn't a smi.
-  JumpIfSmi(function, miss);
+  Label non_instance;
+  if (miss_on_bound_function) {
+    // Check that the receiver isn't a smi.
+    JumpIfSmi(function, miss);
 
-  // Check that the function really is a function.
-  CmpObjectType(function, JS_FUNCTION_TYPE, result);
-  j(not_equal, miss);
+    // Check that the function really is a function.
+    CmpObjectType(function, JS_FUNCTION_TYPE, result);
+    j(not_equal, miss);
 
-  if (miss_on_bound_function) {
     // If a bound function, go to miss label.
     mov(scratch,
         FieldOperand(function, JSFunction::kSharedFunctionInfoOffset));
     BooleanBitTest(scratch, SharedFunctionInfo::kCompilerHintsOffset,
                    SharedFunctionInfo::kBoundFunction);
     j(not_zero, miss);
+
+    // Make sure that the function has an instance prototype.
+    movzx_b(scratch, FieldOperand(result, Map::kBitFieldOffset));
+    test(scratch, Immediate(1 << Map::kHasNonInstancePrototype));
+    j(not_zero, &non_instance);
   }
 
-  // Make sure that the function has an instance prototype.
-  Label non_instance;
-  movzx_b(scratch, FieldOperand(result, Map::kBitFieldOffset));
-  test(scratch, Immediate(1 << Map::kHasNonInstancePrototype));
-  j(not_zero, &non_instance);
-
   // Get the prototype or initial map from the function.
   mov(result,
       FieldOperand(function, JSFunction::kPrototypeOrInitialMapOffset));
 
   // If the prototype or initial map is the hole, don't return it and
   // simply miss the cache instead. This will allow us to allocate a
   // prototype object on-demand in the runtime system.
   cmp(result, Immediate(isolate()->factory()->the_hole_value()));
   j(equal, miss);
 
   // If the function does not have an initial map, we're done.
   Label done;
   CmpObjectType(result, MAP_TYPE, scratch);
   j(not_equal, &done);
 
   // Get the prototype from the initial map.
   mov(result, FieldOperand(result, Map::kPrototypeOffset));
-  jmp(&done);
 
-  // Non-instance prototype: Fetch prototype from constructor field
-  // in initial map.
-  bind(&non_instance);
-  mov(result, FieldOperand(result, Map::kConstructorOffset));
+  if (miss_on_bound_function) {
+    jmp(&done);
+
+    // Non-instance prototype: Fetch prototype from constructor field
+    // in initial map.
+    bind(&non_instance);
+    mov(result, FieldOperand(result, Map::kConstructorOffset));
+  }
 
   // All done.
   bind(&done);
 }
 
 
 void MacroAssembler::CallStub(CodeStub* stub, TypeFeedbackId ast_id) {
   ASSERT(AllowThisStubCall(stub));  // Calls are not allowed in some stubs.
   call(stub->GetCode(), RelocInfo::CODE_TARGET, ast_id);
 }
@@ skipping 1393 matching lines @@
   if (ms.shift() > 0) sar(edx, ms.shift());
   mov(eax, dividend);
   shr(eax, 31);
   add(edx, eax);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32