chrome/test/data/dromaeo/tests/sunspider-bitops-3bit-bits-in-byte.html

   1 <html>
   2 <head>
   3 <script src="../htmlrunner.js"></script>
   4 <script>
   5 // Copyright (c) 2004 by Arthur Langereis (arthur_ext at domain xfinitegames, tld com
   6
   7 // 1 op = 6 ANDs, 3 SHRs, 3 SHLs, 4 assigns, 2 ADDs
   8 // O(1)
   9 function fast3bitlookup(b) {
  10 var c, bi3b = 0xE994; // 0b1110 1001 1001 0100; // 3 2 2 1  2 1 1 0
  11 c  = 3 & (bi3b >> ((b << 1) & 14));
  12 c += 3 & (bi3b >> ((b >> 2) & 14));
  13 c += 3 & (bi3b >> ((b >> 5) & 6));
  14 return c;
  15
  16 /*
  17 lir4,0xE994; 9 instructions, no memory access, minimal register dependence, 6 shifts, 2 adds, 1 inline assign
  18 rlwinmr5,r3,1,28,30
  19 rlwinmr6,r3,30,28,30
  20 rlwinmr7,r3,27,29,30
  21 rlwnmr8,r4,r5,30,31
  22 rlwnmr9,r4,r6,30,31
  23 rlwnmr10,r4,r7,30,31
  24 addr3,r8,r9
  25 addr3,r3,r10
  26 */
  27 }
  28
  29
  30 function TimeFunc(func) {
  31 var x, y, t;
  32 for(var x=0; x<250; x++)
  33 for(var y=0; y<256; y++) func(y);
  34 }
  35
  36 window.onload = function(){ startTest("sunspider-bitops-3bit-bits-in-byte", '3664f684');
  37
  38 test("3bit bits in byte", function(){
  39         TimeFunc(fast3bitlookup);
  40 });
  41
  42 endTest(); };
  43 </script>
  44 </head>
  45 <body></body>
  46 </html>