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Re: Add __builtin_clrsb, similar to clz/ctz

On 06/20/2011 12:38 PM, Bernd Schmidt wrote:
> D'oh. Blackfin has a (clrsb:HI (operand:SI)) instruction, so adding this
> showed a problem with some of the existing simplify_const_unop cases:
> for ffs/clz/ctz/clrsb/parity/popcount, we should look at the mode of the
> operand, rather than the mode of the operation. This limits what we can
> do in that function, since op_mode is sometimes VOIDmode - we really
> should add builtin folders for these at some point.
> 
> New patch below. Retested on i686 and bfin.
> 

Ok.

I'm not going to bike-shed the function name.  If, at some point
before 4.7 is released we agree on another name, we can change it.


r~
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