clock cycles reading data from RAM

hi

i'm trying to make an PWM of an sine wave, 

i'm going to save my look_up table in the RAM of the MSP430G2553 .

i'm going to use one timer in up/down mode, the register TA0CCR0, will be fixed, to set the period of my carrier signal

but registers TA0CCR1 and TA0CCR2 need to be updated each time an CCIFG occurred. that mean i need to 

write something like this 

switch(TA0IV)

{

case  0x02 : TA0CCR1 = look_up_sine[pointer_position] ; break ;

case 0x04 : TA0CCR2 = look_up_sine[pointer_position] ; break ;

....

}

what i need to know is :

1) clock cycle of the switch statement

2) clock cycle of this operation : TA0CCR1 = look_up_sine[pointer_position] ;

thank you