(c) Describe the purpose of the value maintained in register %rcx.

(d) Does the main loop progress forward or backward through str? Justify your answer.

#include int mystery (char*, int) char *str "Good mood food." void main int n -15 printf ("The return: return value was: %d. ", mystery (str ,n)); .globl mystery 2 3 mysterY: $0, %eax movl leaq %rdi, %rsi), %rcx loop: 7 8 9 10 jle endl decq jne loop incl %ead jmp loop 12 13 14 15 16 endl: ret