#include <libregexis024vm/vm_opcodes.h>

#ifndef __ORDER_LITTLE_ENDIAN__
#error "Big endian is currently unsupported"
#endif

bool vmprog_check_inboundness(regex_near_ptr_t prgSz, regex_near_ptr_t IP, regex_near_ptr_t region) {
    return IP + region <= prgSz;
}

uint8_t vmprog_extract_b(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    return prg[(*IPptr)++];
}

uint16_t vmprog_extract_w(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    uint16_t answer = *(uint16_t*)(&prg[*IPptr]);
    *IPptr += 2;
    return answer;
}

uint32_t vmprog_extract_dw(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    uint32_t answer = *(uint32_t *)(&prg[*IPptr]);
    *IPptr += 4;
    return answer;
}

uint64_t vmprog_extract_qw(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    uint64_t answer = *(uint64_t *)(&prg[*IPptr]);
    *IPptr += 8;
    return answer;
}

uint8_t vmprog_extract_instruction(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    return vmprog_extract_b(IPptr, prg);
}

regex_sslot_id_t vmprog_extract_sslot_id(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    return vmprog_extract_dw(IPptr, prg);
}

regex_near_ptr_t vmprog_extract_near_pointer(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    return vmprog_extract_qw(IPptr, prg);
}

regex_tai_t vmprog_extrack_track_array_index(regex_near_ptr_t *IPptr, const uint8_t *prg) {
    return vmprog_extract_w(IPptr, prg);
}