Global symbols in arithmetic operations use one register more than needed

[JordiChauzi]

Global symbols are not treated as 32-bit immediates in arithmetic instructions. We are losing one move.

Code:

#include <stdint.h>

uint8_t dpu_mram_buffer[(8 << 20)];

extern void bar(uint8_t *ptr);

void foo(uint32_t i) {
    bar(dpu_mram_buffer+i);
}

Output:

foo:                                    // @foo
        sd r22, 0, d22
        add r22, r22, 8
        move r1, dpu_mram_buffer
        add r0, r1, r0
        call r23, bar
        ld d22, r22, -8
        jump r23

https://dpu.dev/z/WI12nI