argv arithmetic

Every number on the command line gets added into one total. The args box already holds four of them.

main receives argc in x0argument and return register (x0-x7): carries the first eight arguments and the return value. and argv, an array of string pointers, in x1argument and return register (x0-x7): carries the first eight arguments and the return value.. Entry zero is the program's own name, so start at one. Each entry is eight bytes, which is what the scaled form ldr x0, [argv_r, i_r, lsl 3] is for; bl atoi turns the string into a number.

Change the args box and run again: the total should follow.

what is checked

• the total of the arguments is printed on its own line
• the program exits cleanly
• the numbers really come from argv (atoi called, total not written in)