Hello Everyone....
I am trying to write the wrapper class for PIC24FJ256GB210 controller using the MPLAB C30 compiler v3.25 . An outline of the assembly code wrapper is as below

  
#include 
#include  
#include "ISR_Support.h"

.set        nomips16
 .set         noreorder
 
 .externvUART_ISR_Handler

.externxISRStackTop

 .global_U1TXInterrupt

.set        noreorder
.set         noat
.ent      _U1TXInterrupt

_U1TXInterrupt:
portSAVE_CONTEXT
jalvUART_ISR_Handler
nop
portRESTORE_CONTEXT

.end_U1TXInterrupt

The included file "sys/asm.h" is a C32 file . I need to know which file needs to be included for the C30 compiler and also the best method to handle interrupts.

Sorry I'm not sure what it is you are trying to achieve. You mention a PIC24 MCU but have posted PIC32 code. Which MCU family are you writing the code for? If a PIC24 then you do not need the wrapper. The documentation page for the PIC24 code has the following text in the "Interrupt Service Routines" section:

“Interrupt service routines that cannot cause a context switch have no special requirements and can be written as per the compiler documentation.

Interrupt service routines that can cause a context switch must execute with priority portKERNEL_INTERRUPT_PRIORITY, and only call taskYIELD() at the very end of the service routine after the interrupt source has been cleared. See the file serial.c included in the demo application for an example.”

Regards.