Revert of Revert of X87: Reimplement Maps and Sets in JS

src/x87/code-stubs-x87.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_X87
 
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 2168 matching lines @@
   }
 
   // Call C function.
   __ mov(Operand(esp, 0 * kPointerSize), edi);  // argc.
   __ mov(Operand(esp, 1 * kPointerSize), esi);  // argv.
   __ mov(Operand(esp, 2 * kPointerSize),
          Immediate(ExternalReference::isolate_address(isolate())));
   __ call(ebx);
   // Result is in eax or edx:eax - do not destroy these registers!
 
-  // Runtime functions should not return 'the hole'.  Allowing it to escape may
-  // lead to crashes in the IC code later.
-  if (FLAG_debug_code) {
-    Label okay;
-    __ cmp(eax, isolate()->factory()->the_hole_value());
-    __ j(not_equal, &okay, Label::kNear);
-    __ int3();
-    __ bind(&okay);
-  }
-
   // Check result for exception sentinel.
   Label exception_returned;
   __ cmp(eax, isolate()->factory()->exception());
   __ j(equal, &exception_returned);
 
   // Check that there is no pending exception, otherwise we
   // should have returned the exception sentinel.
   if (FLAG_debug_code) {
     __ push(edx);
     __ mov(edx, Immediate(isolate()->factory()->the_hole_value()));
@@ skipping 2859 matching lines @@
                            ApiParameterOperand(2), kStackSpace, nullptr,
                            Operand(ebp, 7 * kPointerSize), NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X87