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[Bug target/40697] inefficient code to extract least bits from an integer value



------- Comment #2 from steven at gcc dot gnu dot org  2009-07-09 09:59 -------
Maybe we can fix this in expand instead: if we see (x & CONST) and CONST is a
masking constant that isn't a legitimate constant for the the target, then see
if the sum of the rtx_cost of expressing the mask as shifts is less than the
rtx_cost of a load and an AND.

I think (but I'm not sure...) that if you do this with a peephole, you're too
late to avoid the constant pool.

Is this also a size issue?


-- 

steven at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-07-09 09:59:30
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40697


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