5.76 · exercise

Predict: binary logic

For each shift, mask, and sign-extension snippet, give the exact value left in the destination register.

0 of 4 correct

mov w20, 5
lsl w19, w20, 3

What value does w19 hold after these two instructions? Answer in decimal.

mov w20, -8
lsr w19, w20, 1

What value does w19 hold after the shift? Write it as 0x followed by eight hex digits.

mov w22, 0xB7
mov w23, 0x0F
bic w24, w22, w23

Write the low 8 bits of w24 as eight binary digits, with no prefix.

mov w20, 0xFF
sxtb w19, w20

What value does w19 hold after the sign extension? Write it as 0x followed by eight hex digits.