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 // Copyright (c) 2004 by Arthur Langereis (arthur_ext at domain xfinitegames, tld com

 // 1 op = 6 ANDs, 3 SHRs, 3 SHLs, 4 assigns, 2 ADDs

 // O(1)

 function fast3bitlookup(b) {

 var c, bi3b = 0xE994; // 0b1110 1001 1001 0100; // 3 2 2 1  2 1 1 0

 c  = 3 & (bi3b >> ((b << 1) & 14));

 c += 3 & (bi3b >> ((b >> 2) & 14));

 c += 3 & (bi3b >> ((b >> 5) & 6));

 return c;

 /*

 lir4,0xE994; 9 instructions, no memory access, minimal register dependence, 6 shifts, 2 adds, 1 inline assign

 rlwinmr5,r3,1,28,30

 rlwinmr6,r3,30,28,30

 rlwinmr7,r3,27,29,30

 rlwnmr8,r4,r5,30,31

 rlwnmr9,r4,r6,30,31

 rlwnmr10,r4,r7,30,31

 addr3,r8,r9

 addr3,r3,r10

 */

 }

 var ret = 0;

 function TimeFunc(func) {

   var x, y, t;

   for(var x=0; x<500; x++)

   for(var y=0; y<256; y++) {

     ret += func(y);

   }

 }

 TimeFunc(fast3bitlookup);

 assertEq(ret, 512000)