The Tor Browser / file diff

     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/js/src/devtools/jint/sunspider/bitops-3bit-bits-in-byte.js	Wed Dec 31 06:09:35 2014 +0100
     1.3 @@ -0,0 +1,37 @@
     1.4 +// Copyright (c) 2004 by Arthur Langereis (arthur_ext at domain xfinitegames, tld com
     1.5 +
     1.6 +// 1 op = 6 ANDs, 3 SHRs, 3 SHLs, 4 assigns, 2 ADDs
     1.7 +// O(1)
     1.8 +function fast3bitlookup(b) {
     1.9 +var c, bi3b = 0xE994; // 0b1110 1001 1001 0100; // 3 2 2 1  2 1 1 0
    1.10 +c  = 3 & (bi3b >> ((b << 1) & 14));
    1.11 +c += 3 & (bi3b >> ((b >> 2) & 14));
    1.12 +c += 3 & (bi3b >> ((b >> 5) & 6));
    1.13 +return c;
    1.14 +
    1.15 +/*
    1.16 +lir4,0xE994; 9 instructions, no memory access, minimal register dependence, 6 shifts, 2 adds, 1 inline assign
    1.17 +rlwinmr5,r3,1,28,30
    1.18 +rlwinmr6,r3,30,28,30
    1.19 +rlwinmr7,r3,27,29,30
    1.20 +rlwnmr8,r4,r5,30,31
    1.21 +rlwnmr9,r4,r6,30,31
    1.22 +rlwnmr10,r4,r7,30,31
    1.23 +addr3,r8,r9
    1.24 +addr3,r3,r10
    1.25 +*/
    1.26 +}
    1.27 +
    1.28 +
    1.29 +function TimeFunc(func) {
    1.30 +var x, y, t;
    1.31 +/* BEGIN LOOP */
    1.32 +for(var x=0; x<500; x++) {
    1.33 +	/* BEGIN LOOP */
    1.34 +for(var y=0; y<256; y++) func(y);
    1.35 +	/* END LOOP */
    1.36 +}
    1.37 +/* END LOOP */
    1.38 +}
    1.39 +
    1.40 +TimeFunc(fast3bitlookup);