Documentation: fix comments for CommuteCondition.

src/x64/assembler-x64.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 308 matching lines @@
 
 // Returns the equivalent of !cc.
 // Negation of the default no_condition (-1) results in a non-default
 // no_condition value (-2). As long as tests for no_condition check
 // for condition < 0, this will work as expected.
 inline Condition NegateCondition(Condition cc) {
   return static_cast<Condition>(cc ^ 1);
 }
 
 
-// Commute a condition such that a cond b == b cond' b.
+// Commute a condition such that {a cond b == b cond' a}.
 inline Condition CommuteCondition(Condition cc) {
   switch (cc) {
     case below:
       return above;
     case above:
       return below;
     case above_equal:
       return below_equal;
     case below_equal:
       return above_equal;
@@ skipping 1241 matching lines @@
  private:
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_ASSEMBLER_X64_H_