Request for reviews (M): 6769124 various 64-bit fixes for c1

[Roland Westrelin]

http://cr.openjdk.java.net/~roland/6769124/webrev.00/

These are 64-bit fixes to c1 that were first performed as part of the RTS  
development. The problems are listed in the CR (linked from the webrev).  
Each fix is relatively simple but there are 10 or so in the webrev. Tests  
are included for the bugs that can't be reproduced with existing tests.

Roland.