Method multiply256

core/src/main/java/io/questdb/std/Decimal256.java:2480–2599

(long hh, long hl, long lh, long ll)

    }

    private void multiply256(long hh, long hl, long lh, long ll) {
        // Perform 256-bit × 256-bit multiplication
        // Result is at most 512 bits, but we keep only the lower 256 bits

        // Split this into eight 32-bit parts
        long a7 = this.hh >>> 32;
        long a6 = this.hh & 0xFFFFFFFFL;
        long a5 = this.hl >>> 32;
        long a4 = this.hl & 0xFFFFFFFFL;
        long a3 = this.lh >>> 32;
        long a2 = this.lh & 0xFFFFFFFFL;
        long a1 = this.ll >>> 32;
        long a0 = this.ll & 0xFFFFFFFFL;

        long b7 = hh >>> 32;
        long b6 = hh & 0xFFFFFFFFL;
        long b5 = hl >>> 32;
        long b4 = hl & 0xFFFFFFFFL;
        long b3 = lh >>> 32;
        long b2 = lh & 0xFFFFFFFFL;
        long b1 = ll >>> 32;
        long b0 = ll & 0xFFFFFFFFL;

        // Compute all partial products
        long p00 = a0 * b0;
        long p01 = a0 * b1;
        long p02 = a0 * b2;
        long p03 = a0 * b3;
        long p04 = a0 * b4;
        long p05 = a0 * b5;
        long p06 = a0 * b6;
        long p07 = a0 * b7;
        long p10 = a1 * b0;
        long p11 = a1 * b1;
        long p12 = a1 * b2;
        long p13 = a1 * b3;
        long p14 = a1 * b4;
        long p15 = a1 * b5;
        long p16 = a1 * b6;
        long p17 = a1 * b7;
        long p20 = a2 * b0;
        long p21 = a2 * b1;
        long p22 = a2 * b2;
        long p23 = a2 * b3;
        long p24 = a2 * b4;
        long p25 = a2 * b5;
        long p26 = a2 * b6;
        long p27 = a2 * b7;
        long p30 = a3 * b0;
        long p31 = a3 * b1;
        long p32 = a3 * b2;
        long p33 = a3 * b3;
        long p34 = a3 * b4;
        long p35 = a3 * b5;
        long p36 = a3 * b6;
        long p37 = a3 * b7;
        long p40 = a4 * b0;
        long p41 = a4 * b1;