l63               127 src/dps8/dps8_math128.c     uint64_t l63 = al63 + bl63;    // low 63 bits of a + b, with carry into bit 64
l63               128 src/dps8/dps8_math128.c     uint64_t c63 = l63 & SIGN64;   // the carry out of low 63 a + b
l63               129 src/dps8/dps8_math128.c     l63 &= MASK63;                 // lose the carry bit
l63               137 src/dps8/dps8_math128.c     l64 |= l63;                          // put low 63 bits in