How to know what pin triggered an interrupt?

[xnihilo]

I would read the port as fast as possible (immediately on interrupt) by saving it in an 8-bit
variable, and then testing for the port bit in question stored in my variable.

MyPort VAR BYTE. MyPort=PORTA. Now test bits in MyPort for the change.

Edit:
The only interrupt flags available are those shown in the data sheet.

That's exactly what I'm doing (see my code below) but I have the feeling it makes me waste some time doing all the stuff only to know which pin triggered the int

DISABLE 				'disable individual interrupts while executing the interrupt routine (do not put check interrupts calls after each instruction)


in_sig: 


'MEMO: first read the port THEN clear the flag otherwise mismatch still exists
'Contribution from: Darrel Taylor (www.picbasic.co.uk/forum/)
a = porta               'read port to clear mismatch

'TEST block
HIGH portc.2

'check what pin triggered the int
'we have the time of the header pulse to manage that work
if (a.0(0) == 0) THEN
    pin = 0
    GOTO got_pin        'bypass 
ENDIF
if (a.0(1) == 0) THEN
    pin = 1
    GOTO got_pin        'bypass 
ENDIF
if (a.0(2) == 0) THEN
    pin = 2
    GOTO got_pin        'bypass 
ENDIF
if (a.0(3) == 0) THEN
    pin = 3
    GOTO got_pin        'bypass 
ENDIF
if (a.0(4) == 0) THEN
    pin = 4
    GOTO got_pin        'bypass 
ENDIF

got_pin:

This works, then I have to use porta.0(pin).