TestMul64to128(t *testing.T) { a := uint64(5) b := uint64(5) r := mul64(a, b) if r.lo != 0x19 || r.hi != 0 { t.Errorf("lo-range wide mult failed, got %d + %d*(2**64)", r.lo, r.hi) } a = uint64(18014398509481983) // 2^54 - 1 b = uint64(18014398509481983) // 2^54 - 1 r = mul64(a, b) if r.lo != 0xff80000000000001 || r.hi != 0xfffffffffff { t.Errorf("hi-range wide mult failed, got %d + %d*(2**64)", r.lo, r.hi) } a = uint64(1125899906842661) b = uint64(2097155) r = mul64(a, b) r = addMul64(r, a, b) r...