Fibonacci functions. You will write three functions, each of which computes Fibonacci numbers.

Question

Write the assembly code for the functions fibonacci_recursive.s, fibonacci_iterative.s, fibonacci_closed.s. Provide the assembly code as the answers for all three functions separately.

main.c code

#include <stdio.h>

#include <inttypes.h>

#include <math.h>

uint64_t fibonacci_recursive(uint64_t n);

uint64_t fibonacci_iterative(uint64_t n);

uint64_t fibonacci_closed(uint64_t n);

double phi;

int main() {

uint64_t n;

scanf("%" SCNu64, &n);

phi = (1.0 + sqrt(5.0)) / 2.0;

printf("Recursive: %" PRIu64 "\n", fibonacci_recursive(n));

printf("Iterative: %" PRIu64 "\n", fibonacci_iterative(n));

printf("Closed: %" PRIu64 "\n", fibonacci_closed(n));

return 0;

}

Code for the functions:

#include <stdio.h>

#include <inttypes.h>

#include <math.h>

uint64_t fibonacci_recursive(uint64_t n);

uint64_t fibonacci_iterative(uint64_t n);

uint64_t fibonacci_closed(uint64_t n);

double phi;

int main() {

    uint64_t n;

    scanf("%" SCNu64, &n);

    phi = (1.0 + sqrt(5.0)) / 2.0;

    

    printf("Recursive: %" PRIu64 "\n", fibonacci_recursive(n));

    printf("Iterative: %" PRIu64 "\n", fibonacci_iterative(n));

    printf("Closed: %" PRIu64 "\n", fibonacci_closed(n));

    

    return 0;

}

uint64_t fibonacci_recursive(uint64_t n)

{

    if(n == 0)

        return 0;

    else if (n == 1)

        return  1;

    return (fibonacci_recursive(n - 1) + fibonacci_recursive(n - 2));

}

uint64_t fibonacci_iterative(uint64_t n)

{

    uint64_t fn = 1, fn_1 = 0;

    for(int i = 2; i <= n; i++)

    {

        uint64_t temp = fn + fn_1;

        fn_1 = fn;

        fn = temp;

    }

    return fn;

}

uint64_t fibonacci_closed(uint64_t n)

{

    return (pow(phi,n) - pow(-1,n)/pow(phi,n))/sqrt(5);

}

Answer 1

fibonacci_recursive:

push r14

push rbx

push rax

mov rbx, rdi

xor r14d, r14d

cmp rdi, 2

jb .B2

.B1:

lea rdi, [rbx - 1]

call fibonacci_recursive

add rbx, -2

add r14, rax

cmp rbx, 1

ja .B1

.B2:

add r14, rbx

mov rax, r14

add rsp, 8

pop rbx

pop r14

ret