[Bug target/49687] [4.6 Regression][avr] Missed optimization for widening MUL

[gjl at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49687

--- Comment #8 from Georg-Johann Lay <gjl at gcc dot gnu.org> 2011-08-11 07:50:42 UTC ---
Author: gjl
Date: Thu Aug 11 07:50:37 2011
New Revision: 177648

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=177648
Log:

    PR target/49687
    * config/avr/avr.md (smulqi3_highpart): New insn.
    (umulqi3_highpart): New insn.
    (*subqi3.ashiftrt7): New insn.
    (smulhi3_highpart): New expander.
    (umulhi3_highpart): Nex expander.
    (*smulhi3_highpart_call): New insn.
    (*umulhi3_highpart_call): New insn.
    (extend_u): New code attribute.
    (extend_prefix): Rename code attribute to extend_su.
    * config/avr/avr.c (avr_rtx_costs): Report costs of highpart of
    widening QI/HI multiply.


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