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Re: RFC: Simplify rules for ctz/clz patterns and RTL
>>>>> Segher Boessenkool writes:
>> I think the cost would be something like:
>> + case POPCOUNT:
>> + *total = COSTS_N_INSNS (3);
>> + return false;
Segher> Is that the cost when using popcountb? It is a lot more
Segher> expensive when that instruction isn't available (like on
Segher> most current machines).
Yes, but do we even create POPCOUNT rtx if the insn isn't
supported? Wouldn't we expand or create libcall early?
David