Fix a bunch of spelling mistakes :\

src/macro-assembler-arm.cc

 // Copyright 2006-2008 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 895 matching lines @@
   Abort(msg);
   // will not return here
   bind(&L);
 }
 
 
 void MacroAssembler::Abort(const char* msg) {
   // We want to pass the msg string like a smi to avoid GC
   // problems, however msg is not guaranteed to be aligned
   // properly. Instead, we pass an aligned pointer that is
-  // a proper v8 smi, but also pass the aligment difference
+  // a proper v8 smi, but also pass the alignment difference
   // from the real pointer as a smi.
   intptr_t p1 = reinterpret_cast<intptr_t>(msg);
   intptr_t p0 = (p1 & ~kSmiTagMask) + kSmiTag;
   ASSERT(reinterpret_cast<Object*>(p0)->IsSmi());
 #ifdef DEBUG
   if (msg != NULL) {
     RecordComment("Abort message: ");
     RecordComment(msg);
   }
 #endif
   mov(r0, Operand(p0));
   push(r0);
   mov(r0, Operand(Smi::FromInt(p1 - p0)));
   push(r0);
   CallRuntime(Runtime::kAbort, 2);
   // will not return here
 }
 
 } }  // namespace v8::internal