pnx/m16vm
1
0
Fork 0
mirror of https://github.com/pnx/m16vm synced 2026-06-16 03:44:55 +02:00
Code Releases Activity

vm/mm.c: remove base_addr variable, we can do the stuff with macros and pointer casts :)

Browse source
This commit is contained in:
Henrik Hautakoski 2019-04-25 14:29:44 +02:00
parent 67a272b715
commit e92b7ee551
No known key found for this signature in database
GPG key ID: 839F3A7EAFAEAFAA
1 changed files with 11 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

21
vm/mm.c
View file

@ -26,29 +26,30 @@
#define MEM_SIZE 65536
#endif
// Get a WORD aligned (16-bit) address.
// Casts the 8-bit pointer (memory) to 16-bit (WORD) and add offset.
#define addr_align_word(offset) \
(((uint16_t*) memory) + (offset))
#define EXCEPTION_STRING "Runtime exception: Memory address '%u' is out of bounds.\n"
int16_t* base_addr = NULL;
uint8_t *memory = NULL;
#define __check_bounds(addr) \
if ((addr) > MEM_SIZE) { \
if ((addr) + 1 > MEM_SIZE) { \
fprintf(stderr, EXCEPTION_STRING, addr);\
exit(1); \
}
void mm_init() {
base_addr = malloc(MEM_SIZE);
memory = (uint8_t*) base_addr;
memory = (uint8_t*) malloc(MEM_SIZE);
}
void mm_exit() {
if (base_addr) {
free(base_addr);
base_addr = NULL;
if (memory) {
free(memory);
memory = NULL;
}
}
@ -57,12 +58,12 @@ void mm_sw(uint16_t addr, int16_t value) {
__check_bounds(addr);
base_addr[addr] = value;
*addr_align_word(addr) = value;
}
int16_t mm_lw(uint16_t addr) {
__check_bounds(addr);
return base_addr[addr];
return *addr_align_word(addr);
}