[assembler] Remove unnecessary cast.

src/x87/assembler-x87-inl.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 214 matching lines @@
   Address location = pc_ + Assembler::kPatchDebugBreakSlotAddressOffset;
   return Assembler::target_address_at(location, host_);
 }
 
 
 void RelocInfo::set_debug_call_address(Address target) {
   DCHECK(IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence());
   Address location = pc_ + Assembler::kPatchDebugBreakSlotAddressOffset;
   Assembler::set_target_address_at(isolate_, location, host_, target);
   if (host() != NULL) {
-    Object* target_code = Code::GetCodeFromTargetAddress(target);
-    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(
-        host(), this, HeapObject::cast(target_code));
+    Code* target_code = Code::GetCodeFromTargetAddress(target);
+    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(host(), this,
+                                                                  target_code);
   }
 }
 
 
 void RelocInfo::WipeOut() {
   if (IsEmbeddedObject(rmode_) || IsExternalReference(rmode_) ||
       IsInternalReference(rmode_)) {
     Memory::Address_at(pc_) = NULL;
   } else if (IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_)) {
     // Effectively write zero into the relocation.
@@ skipping 297 matching lines @@
 
 Operand::Operand(Immediate imm) {
   // [disp/r]
   set_modrm(0, ebp);
   set_dispr(imm.x_, imm.rmode_);
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_X87_ASSEMBLER_X87_INL_H_