LP-MSPM0G3507: How the startup code of mspm0g3507 works.

I am using mspm0g3507 IC and when I was checking the startup code, I saw the following comment in that file.
"SystemInit can be called here, but not necessary for MSPM0".

Can someone tell me about this in some detail. 

I want to understand startup sequence code of mspm0g3507(IDE: IAR and Keil). 

file name: startup_mspm0g3507_uvision.s

Reset_Handler PROC
EXPORT Reset_Handler [WEAK]
;IMPORT SystemInit
IMPORT __main
; SystemInit can be called here, but not necessary for MSPM0
;LDR R0, =SystemInit
;BLX R0
LDR R0, =__main
BX R0
ENDP

file name: startup_mspm0g3507_iar.c

__weak void Reset_Handler(void)
{
/* Initialize the device */
// SystemInit();

/* Call the application's entry point. */
__iar_program_start();
}