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[Bug rtl-optimization/50037] Unroll factor exceeds max trip count


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50037

Michael Matz <matz at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |matz at gcc dot gnu.org

--- Comment #4 from Michael Matz <matz at gcc dot gnu.org> 2011-08-10 16:56:47 UTC ---
(In reply to comment #3)
> Using
> 
> int foo (int n, int *addr)
> {
>   int count, sum;
>   for ( count = n & 0x3; count >= 0; count--, addr++ )
>     sum += *addr;
>   return sum;
> }
> 
> it works.

Not for me.  It's still unrolled by 7.

> neither works with
> 
> int foo (int n, int *addr)
> {
>   int count, sum;
>   for ( count = 0; count < n & 0x3; count++, addr++ )

Careful.  Operator precedence.  count < (n & 3)

Doesn't work with those examples either, though.


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