[Sdcc-user] Pic port ISR generation problem

[<pa...@li...>]

Hi all the ML,
may be i'm doing some mistake since i'm really not a C guru, but please give
a look at this problem...

Compiling the following isr_test.c file and searching in the generated asm
file,
it seems that SDCC generates a wrong code in the start of  the interrupt
routine that makes it not working
( GOTO END_OF_INTERRUPT+1 look at the extracted part of isr_test.asm file
down here).

Searching in the sdcc source, i see that the code is generated by gen.c
source in /sdcc/src/pic directory at the line 2697:
addpCode2pBlock(pb,newpCode(POC_GOTO,newpCodeOp("END_OF_INTERRUPT+1",PO_STR)
));
      emitpcodeNULLop(POC_NOP);
      emitpcodeNULLop(POC_NOP);
      emitpcodeNULLop(POC_NOP);

Commenting out these four lines and rebuilting SDCC seem to generate working
code again...at least i hope it :-)
Please give it a try and let me know.

Bye,
Onny.

/////   Start of isr_test.c  /////
#include <p16f877.h>

typedef unsigned int word;

word at 0x2007  __CONFIG = _CP_OFF & _WDT_OFF & _BODEN_ON & \
         _PWRTE_ON & _XT_OSC & _WRT_ENABLE_ON & \
         _LVP_OFF & _DEBUG_OFF & _CPD_OFF;

void isr() interrupt 0 {
  TMR2IF=0;    // just for make it generate something...
}

void main(void)
{
     PORTA=255;
}
///////////////////////////////////////////////// END OF isr_test.c



^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
extracted from the genarated isr_test.asm
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
;--------------------------------------------------------
; reset and interrupt vectors
;--------------------------------------------------------
STARTUP code
 goto __sdcc_gsinit_startup
 nop
 nop
 goto __sdcc_interrupt
;--------------------------------------------------------
; initialization and interrupt code
;--------------------------------------------------------
code_init code 0x10
__sdcc_gsinit_startup:
;***
;  pBlock Stats: dbName = D
;***
;; Starting pCode block

 pagesel _main
 goto _main
__sdcc_interrupt:
;***
;  pBlock Stats: dbName = I
;***
;entry:  _isr ;Function start
; 0 exit points
;; Starting pCode block
_isr ;Function start
; 0 exit points
;#CSRC isr_test.c 11
;  void isr() interrupt 0 {
 GOTO END_OF_INTERRUPT+1       ;;; <------------- Here's the problem...
 NOP
 NOP
 NOP
 MOVWF WSAVE
 SWAPF STATUS,W
 CLRF STATUS
 MOVWF SSAVE
;#CSRC isr_test.c 12
;  TMR2IF=0;    // just for make it generate something
 BCF (_TMR2IF >> 3), (_TMR2IF & 7)
 CLRF STATUS
 SWAPF SSAVE,W
 MOVWF STATUS
 SWAPF WSAVE,F
 SWAPF WSAVE,W
END_OF_INTERRUPT
 RETFIE

 goto $                                  <--------------   The program
remains here!!!!!  (END_OF_INTERRUPT + 1)
;--------------------------------------------------------
; code
;--------------------------------------------------------
code_isr_test code
;***
;  pBlock Stats: dbName = M
;***
;entry:  _main ;Function start
; 2 exit points
;has an exit
;; Starting pCode block
_main ;Function start
; 2 exit points
;#CSRC isr_test.c 19
;  PORTA=255;
 MOVLW 0xff
 MOVWF _PORTA
 RETURN
; exit point of _main

 end