;***************************************************************
;* Macro   LONGC           ;Long Call	;by Walter Quitt
;***************************************************************
LONGC MACRO SUBROUTINE

   bsf     CPUSTA,GLINTD       ;interrupts off
   movlw   HIGH (SUBROUTINE)
   movfp   WREG,PCLATH         ;Z unaffected
   bcf     CPUSTA,GLINTD       ;interrupts on
   lcall   LOW  (SUBROUTINE)

   ENDM

Olin Lathrop [olin at cognivis.com] of cognivis (978) 772-3129 says

;
;********************
;
;   Macro SKIP_WLE
;
;   Skip the next instruction if W was less than or equal to the value
;   it was subtracted from.  This assumes that the carry flag has been
;   preserved from the last SUBWF or SUBLW instruction.
;
skip_wle macro
  if fam_17
         btfss   alusta, c
         exitm
    endif

         btfss   status, c   ;skip if no borrow occurred
         endm
;
;********************
;
;   Macro SKIP_WGT
;
;   Skip the next instruction if W was greater than the value
;   it was subtracted from.  This assumes that the carry flag has been
;   preserved from the last SUBWF or SUBLW instruction.
;
skip_wgt macro
  if fam_17
         btfsc   alusta, c
         exitm
    endif

         btfsc   status, c   ;skip if a borrow occurred
         endm
;
;********************
;
;   Macro SKIP_Z
;
;   Skip the next instruction if the zero flag is set.
;
skip_z   macro
  if fam_17
         btfss   alusta, z
         exitm
    endif

         btfss   status, z
         endm
;
;********************
;
;   Macro SKIP_NZ
;
;   Skip the next instruction if the zero flag is not set.
;
skip_nz  macro
  if fam_17
         btfsc   alusta, z
         exitm
    endif

         btfsc   status, z
         endm
;
;********************
;
;   Macro SKIP_CARR
;
;   Skip the next instruction if a carry occurred.
;
skip_carr macro
  if fam_17
         btfss   alusta, c
         exitm
    endif

         btfss   status, c
         endm
;
;********************
;
;   Macro SKIP_NCARR
;
;   Skip the next instruction if no carry occurred.
;
skip_ncarr macro
  if fam_17
         btfsc   alusta, c
         exitm
    endif

         btfsc   status, c
         endm
;
;********************
;
;   Macro SKIP_BORR
;
;   Skip the next instruction if a borrow occurred.
;
skip_borr macro
  if fam_17
         btfsc   alusta, c
         exitm
    endif

         btfsc   status, c
         endm
;
;********************
;
;   Macro SKIP_NBORR
;
;   Skip the next instruction if no borrow occurred.
;
skip_nborr macro
  if fam_17
         btfss   alusta, c
         exitm
    endif

         btfss   status, c
         endm
;
;********************
;
;   Macro INTR_OFF
;
;   Globally disable interrupts without changing which interrupts are
;   individually disabled.  This macro together with INTR_ON can be used
;   around small sections of code that need to run with interrupts off.
;
intr_off macro
  if fam_16
         bcf     intcon, gie
    endif
  if fam_17
         bsf     cpusta, glintd
    endif
         endm
;
;********************
;
;   Macro INTR_ON
;
;   Globally enable interrupts without changing which interrupts are
;   individually enabled.  This macro together with INTR_OFF can be used
;   around small sections of code that need to run with interrupts off.
;
intr_on  macro
  if fam_16
         bsf     intcon, gie
    endif
  if fam_17
         bcf     cpusta, glintd
    endif
         endm

Simon says:

BETTER?:
 intr_off macro
   if fam_16
 foo:
          bcf     intcon, gie
          btfsc   intcon, gie
          goto    foo
     endif
   if fam_17
 bar:
          bsf     cpusta, glintd
          btfss   cpusta, glintd
          goto    bar
     endif
          endm

cut & paste of the reasoning behind the code from Thomas' code:
;If an IRQ happens when the "bcf intcon,gie" line is executing,
;the GIE bit will be cleared, but the interrupt will still occur.
;If the interrupt routine has a RETFIE instruction at the
;end, (which is the usual state of affairs),then GIE will
;be set to 1 again.

Questions:

• David A Cary of Motorguide Pinpoint asks: "

  What does the LONGC macro do ? Why would anyone ever want to use it ? I'm missing the point."

  .