small misspelling fixes.

src/x64/lithium-codegen-x64.cc

 // Copyright 2013 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 2385 matching lines @@
 
   DeferredInstanceOfKnownGlobal* deferred;
   deferred = new(zone()) DeferredInstanceOfKnownGlobal(this, instr);
 
   Label done, false_result;
   Register object = ToRegister(instr->value());
 
   // A Smi is not an instance of anything.
   __ JumpIfSmi(object, &false_result);
 
-  // This is the inlined call site instanceof cache. The two occurences of the
+  // This is the inlined call site instanceof cache. The two occurrences of the
   // hole value will be patched to the last map/result pair generated by the
   // instanceof stub.
   Label cache_miss;
   // Use a temp register to avoid memory operands with variable lengths.
   Register map = ToRegister(instr->temp());
   __ movq(map, FieldOperand(object, HeapObject::kMapOffset));
   __ bind(deferred->map_check());  // Label for calculating code patching.
   Handle<JSGlobalPropertyCell> cache_cell =
       factory()->NewJSGlobalPropertyCell(factory()->the_hole_value());
   __ movq(kScratchRegister, cache_cell, RelocInfo::GLOBAL_PROPERTY_CELL);
@@ skipping 3313 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64