li x0, program_end
li x1, 512

mv x2, x0

.align 2
loop_write_word:

xori x3, x2, 0xaaa
sw x3, 0(x2)
addi x2, x2, 1
blt x2, x1, loop_write_word

mv x2, x0

.align 2
loop_read_word:

xori x3, x2, 0xaaa
lw x4, 0(x2)
bne x3, x4, error
addi x2, x2, 1
blt x2, x1, loop_read_word

.align 2
loop_write_double:

xori x6, x2, 0xaaa
xori x7, x2, 0x555
sd x67, 0(x2)
addi x2, x2, 2
blt x2, x1, loop_write_double

mv x2, x0

.align 2
loop_read_double:

xori x6, x2, 0xaaa
xori x7, x2, 0x555
ld x45, 0(x2)
bne x4, x6, error
bne x5, x7, error
lw x4, 0(x2)
bne x4, x6, error
lw x5, 1(x2)
bne x5, x7, error
addi x2, x2, 2
blt x2, x1, loop_read_double

success:

li x0, 0
wfi

error:

mv x0, x2
wfi

.align 2
program_end: