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Re: RFC: Simplify rules for ctz/clz patterns and RTL

I think the cost would be something like: 

+    case POPCOUNT:
+      *total = COSTS_N_INSNS (3);
+      return false;


Is that the cost when using popcountb?  It is a lot more
expensive when that instruction isn't available (like on
most current machines).

The rest (i.e. CLZ, CTZ) looks good to me.


Segher

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