5.81 · exercise

Predict: binary arithmetic

Trace a 32-bit add that wraps around, a carry passed from one add to the next, and a signed multiply with a 64-bit result.

0 of 3 correct

mov w20, -1
add w20, w20, 2

What exact decimal value does w20 hold after this code runs?

mov x20, 5
mov x23, 7
mov x21, -1
mov x24, 1
adds x27, x21, x24
adcs x26, x20, x23

What exact decimal value does x26 hold after this code runs?

mov w20, 2
mov w21, -5
smull x22, w20, w21

What exact hex value does x22 hold after this code runs? Write all 16 hex digits, starting with 0x.