testmul.c

#include <avr/io.h>
#include <stdint.h>

int main(void)
{
    /* Replace with your application code */
    while (1) 
    {
		const volatile uint8_t a = 10;
		const volatile uint8_t b = 20;
		volatile uint16_t result = a * b;
    }
}

Output for mega328:
000000cc

:
#include <avr/io.h>
#include <stdint.h>

int main(void)
{
cc: cf 93 push r28
ce: df 93 push r29
d0: 00 d0 rcall .+0 ; 0xd2 <main+0x6>
d2: 00 d0 rcall .+0 ; 0xd4 <main+0x8>
d4: cd b7 in r28, 0x3d ; 61
d6: de b7 in r29, 0x3e ; 62
/* Replace with your application code /
while (1)
{
const volatile uint8_t a = 10;
d8: 3a e0 ldi r19, 0x0A ; 10
const volatile uint8_t b = 20;
da: 24 e1 ldi r18, 0x14 ; 20
int main(void)
{
/ Replace with your application code */
while (1)
{
const volatile uint8_t a = 10;
dc: 3c 83 std Y+4, r19 ; 0x04
const volatile uint8_t b = 20;
de: 2b 83 std Y+3, r18 ; 0x03
volatile uint16_t result = a * b;
e0: 8c 81 ldd r24, Y+4 ; 0x04
e2: 9b 81 ldd r25, Y+3 ; 0x03
e4: 89 9f mul r24, r25
e6: c0 01 movw r24, r0
e8: 11 24 eor r1, r1
ea: 9a 83 std Y+2, r25 ; 0x02
ec: 89 83 std Y+1, r24 ; 0x01
}
ee: f6 cf rjmp .-20 ; 0xdc <main+0x10>

000000f0 <_exit>:
f0: f8 94 cli

000000f2 <__stop_program>:
f2: ff cf rjmp .-2 ; 0xf2 <__stop_program>