Fix problem in r4998. Initialize target of break and continue in fast smi lo...

src/x64/codegen-x64.cc

 // Copyright 2010 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 1627 matching lines @@
     default:
       UNREACHABLE();
   }
   if (initially_false) return;
 
   // Only check loop condition at the end.
 
   Visit(node->init());
 
   JumpTarget loop(JumpTarget::BIDIRECTIONAL);
+  // Set type and stack height of BreakTargets.
+  node->continue_target()->set_direction(JumpTarget::FORWARD_ONLY);
+  node->break_target()->set_direction(JumpTarget::FORWARD_ONLY);
 
   IncrementLoopNesting();
   loop.Bind();
 
   // Set number type of the loop variable to smi.
   CheckStack();  // TODO(1222600): ignore if body contains calls.
 
   SetTypeForStackSlot(loop_var->slot(), TypeInfo::Smi());
   Visit(node->body());
 
@@ skipping 10393 matching lines @@
 }
 
 #endif
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64