8051 megawin MCU register declarations on C

Question

Are these declarations correct?

#include <stdint.h>
#include <stdbool.h>
#include <reg_mg82f6d64.h>

uint8_t data *R0      = 0x00;
uint8_t data *R1      = 0x01;
uint8_t data *R2      = 0x02;
uint8_t data *R3      = 0x03;
uint8_t data *R6      = 0x06;
uint8_t data *R7      = 0x07;

uint16_t code  *DPTRc     = 0x0000;
uint16_t xdata *DPTRx     = 0x0000; // pdata
uint8_t  data  *DPTRd     = 0x00;

uint8_t idata *STACK[10] = {(uint8_t idata *)0x81};

In here I am trying to use them exact same on 8051 assembler with C features but sometime it goes wrong, for example i can not use SP register for PUSH, POP like on assembly.

void wrb(void) // (write read byte)
{
    *STACK[1] = ACC; // i want to do PUSH(ACC);
    while ((SPSTAT & 0x80) != 0); 
    ACC   = STACK[1]; // // i want to do POP(ACC);
    SPDAT = ACC;
    while ((SPSTAT & 0x80) == 0);
    ACC = SPDAT;
}


void PUSH(void)
{
    SP++;
    *(uint8_t idata *)SP = ACC;
}

void POP(void)
{
    ACC = *(uint8_t idata *)SP;
    SP--;
}

So when MCU has Stack Pointer why would i declare another array and use more memory size which is a bad development!