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# This code has been originally copied from max.s
# It has been modified to:
# - Find the smallest value, instead of the largest
# - Use Start/End addresses to delimit the boundaries of the number list
#
# %rax - holds the current element being examined
# %rbx - Holds the smallest number
.section .data
# This version has 2 labels, one to point to the start of the list, and another
# to point to the address right after it, so we can use it to search the list
# boundary.
data_items:
.quad 234,10,9,230,66,77,23,66,101,69,100
data_end:
.section .text
.globl _start
_start:
# Using immediate mode with a label, will give you the ADDRESS of the
# instruction/data it points to. Once the label itself contains an ADDRESS, the
# immediate mode will give you the ADDRESS itself.
# Using direct mode with a label, will give you the DATA into the address the
# label points to. Once the label itself contains an address, the direct mode,
# as expected will give you the DATA into the address pointed by the label.
movq $data_items, %rax
cmpq $data_end, %rax # We need this check here in case
je exit_loop_empty # the items list is empty
movq (%rax), %rbx
loop_start:
addq $8, %rax # We are using QuadWords, so 8 bytes
cmpq $data_end, %rax
je exit_loop
cmpq (%rax), %rbx
jle loop_start
movq (%rax), %rbx
jmp loop_start
exit_loop_empty:
movq $255, %rbx
exit_loop:
movq $1, %rax
int $0x80
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