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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;


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?

I don't know, there's only one way to find out... :-)


Segher

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