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helper for dealing with uint64
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// helper for dealing with uint64 | |
var u64 = function (h, l) { | |
h = h|0; l = l|0; | |
this.hi = h >>> 0; | |
this.lo = l >>> 0; | |
} | |
function new64(num) { | |
var hi = 0, lo = num >>> 0; | |
if ((+(Math.abs(num))) >= 1) { | |
if (num > 0) { | |
hi = ((Math.min((+(Math.floor(num/4294967296))), 4294967295))|0) >>> 0; | |
} else { | |
hi = (~~((+(Math.ceil((num - +(((~~(num)))>>>0))/4294967296))))) >>> 0; | |
} | |
} | |
return new u64(hi, lo); | |
} | |
function shr64(x, c) { | |
var h = 0, l = 0; | |
if (c < 32) { | |
l = (x.lo >>> c) | (x.hi & (((1 << c) - 1)|0)) << (32 - c); | |
h = x.hi >>> c; | |
} else { | |
l = x.hi >>> (c - 32); | |
} | |
return new u64(h, l); | |
} | |
function shl64(x, c) { | |
var h = 0, l = 0; | |
if (c < 32) { | |
h = (x.hi << c) | ((x.lo & (((1 << c) - 1)|0) << (32 - c)) >>> (32 - c)); | |
l = x.lo << c; | |
} else { | |
h = x.lo << (c - 32); | |
} | |
return new u64(h, l); | |
} | |
function rotl64(x, c) { | |
var t1 = shl64(x, c); | |
var t2 = shr64(x, 64 - c); | |
return new u64(t1.hi | t2.hi, t1.lo | t2.lo); | |
} | |
function rotr64(x, c) { | |
return rotl64(x, 64 - c); | |
} | |
function mul(a, b, make64) { | |
make64 = make64|0; | |
var ah, al, bh, bl, c, d, e, x, y, z; // TODO: reduce variable | |
ah = a >>> 16; al = a & 0xffff; | |
bh = b >>> 16; bl = b & 0xffff; | |
c = al*bl; d = ah*bl; e = al*bh; | |
var l = (c + ((d + e) << 16) >>> 0)|0; | |
if (!make64) return l; | |
x = d + (c >>> 16); | |
y = (e + (x & 0xffff)) >>> 16; | |
z = x >>> 16; | |
return new u64((ah*bh + y + z), l); | |
} | |
function mul64(x, y) { | |
var z = mul(x.lo, y.lo, 1); | |
z.hi += ((mul(x.hi, y.lo) + mul(y.hi, x.lo))|0); | |
return z; | |
} | |
function add64() { | |
var a = arguments, t, | |
l = a[0].lo, h = a[0].hi; | |
for (var i = 1; i < a.length; i++) { | |
t = l; l = (t + a[i].lo)>>>0; | |
h = (h + a[i].hi + ((l < t) ? 1 : 0))>>>0; | |
} | |
return new u64(h, l); | |
} | |
function sub64(x, y) { | |
return new u64(x.hi - y.hi - ((x.lo < y.lo) ? 1 : 0), x.lo - y.lo); | |
} | |
function flatten64(x) { | |
// caveat: it will loose precision with big numbers | |
return (x.hi * 4294967296 + x.lo); | |
} | |
function xor64() { | |
var a = arguments, h = a[0].hi, l = a[0].lo; | |
for (var i = 1; i < a.length; i++) { | |
h = (h ^ a[i].hi) >>> 0; | |
l = (l ^ a[i].lo) >>> 0; | |
} | |
return new u64(h, l); | |
} |
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