Handle all kind of arguments in the ToBooleanStub. While this is not very

src/x64/code-stubs-x64.cc

 // Copyright 2011 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 217 matching lines @@
 
   __ bind(&slow_case);
   __ TailCallRuntime(Runtime::kCreateArrayLiteralShallow, 3, 1);
 }
 
 
 void ToBooleanStub::Generate(MacroAssembler* masm) {
   Label false_result, true_result, not_string;
   __ movq(rax, Operand(rsp, 1 * kPointerSize));
 
+  // undefined -> false
+  __ CompareRoot(rax, Heap::kUndefinedValueRootIndex);
+  __ j(equal, &false_result);
+
+  // Boolean -> its value
+  __ CompareRoot(rax, Heap::kFalseValueRootIndex);
+  __ j(equal, &false_result);
+  __ CompareRoot(rax, Heap::kTrueValueRootIndex);
+  __ j(equal, &true_result);
+
+  // Smis: 0 -> false, all other -> true
+  __ Cmp(rax, Smi::FromInt(0));
+  __ j(equal, &false_result);
+  Condition is_smi = __ CheckSmi(rax);
+  __ j(is_smi, &true_result);
+
   // 'null' => false.
   __ CompareRoot(rax, Heap::kNullValueRootIndex);
   __ j(equal, &false_result, Label::kNear);
 
   // Get the map and type of the heap object.
   // We don't use CmpObjectType because we manipulate the type field.
   __ movq(rdx, FieldOperand(rax, HeapObject::kMapOffset));
   __ movzxbq(rcx, FieldOperand(rdx, Map::kInstanceTypeOffset));
 
   // Undetectable => false.
@@ skipping 4858 matching lines @@
   __ Drop(1);
   __ ret(2 * kPointerSize);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64