[Bug target/29560] [avr] Poor optimization for byte shifts

[gjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29560

--- Comment #9 from Georg-Johann Lay <gjl at gcc dot gnu.org> 2011-07-25 
12:48:29 UTC ---
Created attachment 24827
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24827
Fix PR29560 by adding peephole2 pattern.


    PR target/29560
    * config/avr/avr.md: Add peephole2 to map ashlhi3 to ashlqi3 if
    high part of shift target is unused.