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[Bug rtl-optimization/18560] better optimalization of EOR/MOV block.


------- Additional Comments From rearnsha at gcc dot gnu dot org  2004-12-14 15:16 -------
As Andrew pointed out, the merge of the eor and the rotate is now done on
mainline in 4.0.  The initial redundant MOV is a register allocation artifact. 
This particular testcase compiles optimally with the new register allocator:

reverse:
        eor     r3, r0, r0, ror #16
        bic     r3, r3, #16711680
        mov     r3, r3, lsr #8
        eor     r0, r3, r0, ror #8
        bx      lr

but for other reasons, I wouldn't recommend you use that option (too many other
bugs).

-- 
           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |RESOLVED
         Resolution|                            |FIXED
   Target Milestone|---                         |4.0.0


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=18560


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