into
CODE
1: ADDS $t0.lo, $t0.lo, #1 // $t0[31..0] += 1
1: ADD $t1.lo, $t1.lo, #1 // $t1[31..0] += 1
2: ADC $t0.hi, $t0.hi, #0 // $t0[63..32] += carry of $t0[31..0] += 1
2: MOV $t1.hi, $t1.lo, ASR #31 // $t1[63..32] = $t1[31] * 0xFFFFFFFF (0 or -1 according bit 31 of $t1)
of course, the...