[turbofan] support for Int64 in CheckedLoad/CheckedStore on 64-bit platforms.

src/compiler/x87/code-generator-x87.cc

 // Copyright 2013 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/compiler/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/osr.h"
@@ skipping 1206 matching lines @@
       break;
     case kCheckedStoreFloat64:
       ASSEMBLE_CHECKED_STORE_FLOAT(fst_d);
       break;
     case kX87StackCheck: {
       ExternalReference const stack_limit =
           ExternalReference::address_of_stack_limit(isolate());
       __ cmp(esp, Operand::StaticVariable(stack_limit));
       break;
     }
+    case kCheckedLoadWord64:
+    case kCheckedStoreWord64:
+      UNREACHABLE();  // currently unsupported checked int64 load/store.
+      break;
   }
 }  // NOLINT(readability/fn_size)
 
 
 // Assembles a branch after an instruction.
 void CodeGenerator::AssembleArchBranch(Instruction* instr, BranchInfo* branch) {
   X87OperandConverter i(this, instr);
   Label::Distance flabel_distance =
       branch->fallthru ? Label::kNear : Label::kFar;
   Label* tlabel = branch->true_label;
@@ skipping 613 matching lines @@
     int padding_size = last_lazy_deopt_pc_ + space_needed - current_pc;
     __ Nop(padding_size);
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8