wasm-crypto-compiler-issue.ts

// tslint:disable-next-line:no-reference
/// <reference path="../node_modules/assemblyscript/index.d.ts" />

@sealed @unmanaged
class Ge {
    x: Int64Array;
    y: Int64Array;
    z: Int64Array;
    t: Int64Array;

    @inline constructor() {
        this.x = new Int64Array(16);
        this.y = new Int64Array(16);
        this.z = new Int64Array(16);
        this.t = new Int64Array(16);
    }
}

@inline function fe25519Cmov(p: Int64Array, q: Int64Array, b: i64): void {
    let mask = ~(b - 1);
    unchecked(p[0] ^= (p[0] ^ q[0]) & mask);
    unchecked(p[1] ^= (p[1] ^ q[1]) & mask);
    unchecked(p[2] ^= (p[2] ^ q[2]) & mask);
    unchecked(p[3] ^= (p[3] ^ q[3]) & mask);
    unchecked(p[4] ^= (p[4] ^ q[4]) & mask);
    unchecked(p[5] ^= (p[5] ^ q[5]) & mask);
    unchecked(p[6] ^= (p[6] ^ q[6]) & mask);
    unchecked(p[7] ^= (p[7] ^ q[7]) & mask);
    unchecked(p[8] ^= (p[8] ^ q[8]) & mask);
    unchecked(p[9] ^= (p[9] ^ q[9]) & mask);
    unchecked(p[10] ^= (p[10] ^ q[10]) & mask);
    unchecked(p[11] ^= (p[11] ^ q[11]) & mask);
    unchecked(p[12] ^= (p[12] ^ q[12]) & mask);
    unchecked(p[13] ^= (p[13] ^ q[13]) & mask);
    unchecked(p[14] ^= (p[14] ^ q[14]) & mask);
    unchecked(p[15] ^= (p[15] ^ q[15]) & mask);
}

// @inline  // --  comment out this @inline attr will cause to exponential compilation time
function cmov(p: Ge, q: Ge, b: i64): void {
    fe25519Cmov(p.x, q.x, b);
    fe25519Cmov(p.y, q.y, b);
    fe25519Cmov(p.z, q.z, b);
    fe25519Cmov(p.t, q.t, b);
}

export function scalarmult(p: Ge, s: Uint8Array, q: Ge): void {
    let pc = [
        new Ge(), new Ge(),
        new Ge(), new Ge(),
        new Ge(), new Ge(),
        new Ge(), new Ge(),
        new Ge(), new Ge(),
        new Ge(), new Ge(),
        new Ge(), new Ge(),
        new Ge(), new Ge()
    ];

    let t = new Ge();

    for (let i = 252; i >= 0; i -= 4) {
        cmov(t, unchecked(pc[15]), i & 1);
        cmov(t, unchecked(pc[14]), i & 1);
        cmov(t, unchecked(pc[13]), i & 1);
        cmov(t, unchecked(pc[12]), i & 1);
        cmov(t, unchecked(pc[11]), i & 1);
        cmov(t, unchecked(pc[10]), i & 1);
        cmov(t, unchecked(pc[9]),  i & 1);
        cmov(t, unchecked(pc[8]),  i & 1);
        cmov(t, unchecked(pc[7]),  i & 1);
        cmov(t, unchecked(pc[6]),  i & 1);
        cmov(t, unchecked(pc[5]),  i & 1);
        cmov(t, unchecked(pc[4]),  i & 1);
        cmov(t, unchecked(pc[3]),  i & 1);
        cmov(t, unchecked(pc[2]),  i & 1);
        cmov(t, unchecked(pc[1]),  i & 1);
        cmov(t, unchecked(pc[0]),  i & 1);
    }
}