Look at the logic program below. Set a breakpoint after each commented instruction. You can also single step through the
Posted: Fri Jul 08, 2022 6:16 am
Look at the logic program below. Set a breakpoint after eachcommented instruction. You can also single step through theprogram. Answer the questions in the program.
.data
sourceword: .word 0xABwordmask: .word 0xCFoperand: .long 0xAA
.text
.globl _start
_start: movw sourceword, %ax movw %ax, %bx xorw %cx, %cx# What's in ax?# What's in bx?# What's in cx?
andw wordmask, %ax# What's in ax? orw wordmask, %bx# What's in bx? xorw wordmask, %cx# What's in cx?
movl operand, %eax movl %eax, %ebx movl %eax, %ecx# What's in eax?# What's in ebx?# What's in ecx?
shll $3,%eax# What's in eax?
rorl $4,%ebx# What's in ebx?
sarl %ecx# Now what's in ecx?
done:
.data
sourceword: .word 0xABwordmask: .word 0xCFoperand: .long 0xAA
.text
.globl _start
_start: movw sourceword, %ax movw %ax, %bx xorw %cx, %cx# What's in ax?# What's in bx?# What's in cx?
andw wordmask, %ax# What's in ax? orw wordmask, %bx# What's in bx? xorw wordmask, %cx# What's in cx?
movl operand, %eax movl %eax, %ebx movl %eax, %ecx# What's in eax?# What's in ebx?# What's in ecx?
shll $3,%eax# What's in eax?
rorl $4,%ebx# What's in ebx?
sarl %ecx# Now what's in ecx?
done: