js/src/devtools/jint/sunspider/bitops-3bit-bits-in-byte.js@129ffea94266
js/src/devtools/jint/sunspider/bitops-3bit-bits-in-byte.js
Sat, 03 Jan 2015 20:18:00 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Sat, 03 Jan 2015 20:18:00 +0100
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
- permissions
- -rw-r--r--
Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.
1 // Copyright (c) 2004 by Arthur Langereis (arthur_ext at domain xfinitegames, tld com
3 // 1 op = 6 ANDs, 3 SHRs, 3 SHLs, 4 assigns, 2 ADDs
4 // O(1)
5 function fast3bitlookup(b) {
6 var c, bi3b = 0xE994; // 0b1110 1001 1001 0100; // 3 2 2 1 2 1 1 0
7 c = 3 & (bi3b >> ((b << 1) & 14));
8 c += 3 & (bi3b >> ((b >> 2) & 14));
9 c += 3 & (bi3b >> ((b >> 5) & 6));
10 return c;
12 /*
13 lir4,0xE994; 9 instructions, no memory access, minimal register dependence, 6 shifts, 2 adds, 1 inline assign
14 rlwinmr5,r3,1,28,30
15 rlwinmr6,r3,30,28,30
16 rlwinmr7,r3,27,29,30
17 rlwnmr8,r4,r5,30,31
18 rlwnmr9,r4,r6,30,31
19 rlwnmr10,r4,r7,30,31
20 addr3,r8,r9
21 addr3,r3,r10
22 */
23 }
26 function TimeFunc(func) {
27 var x, y, t;
28 /* BEGIN LOOP */
29 for(var x=0; x<500; x++) {
30 /* BEGIN LOOP */
31 for(var y=0; y<256; y++) func(y);
32 /* END LOOP */
33 }
34 /* END LOOP */
35 }
37 TimeFunc(fast3bitlookup);
