[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 #10 from Georg-Johann Lay <gjl at gcc dot gnu.org> 2011-08-10 
08:58:07 UTC ---
Author: gjl
Date: Wed Aug 10 08:58:03 2011
New Revision: 177616

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=177616
Log:

    PR target/29560
    * config/avr/avr.md (*ashlhiqi3): New insn-and-split.
    (*ashl<extend_prefix>qihiqi3): New insn-and-splits.
    (*ashl<extend_prefix>qihiqi3.mem): New insn-and-splits.
    Add peephole2 to map ashlhi3 to ashlqi3 if high part of
    shift target is unused.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/config/avr/avr.md