Added a forced alignment. Shame it makes small allocations bigger but it works for now

This commit is contained in:
Warwick 2025-11-23 21:36:13 +00:00
parent 90ff13c07a
commit 257012f6ac
2 changed files with 7 additions and 4 deletions

View file

@ -21,8 +21,8 @@ Arena arena_init(Arena *parent, size_t capacity) {
if (parent != NULL) { if (parent != NULL) {
// Allocate new arena in parent to reduce likelyhood of loss // Allocate new arena in parent to reduce likelyhood of loss
Arena *current_arena = arena_alloc(parent, sizeof(Arena)); Arena *current_arena = arena_alloc(parent, sizeof(Arena));
*current_arena = (Arena){ *current_arena =
.begin = region, .end = region, .child = NULL, .sibling = NULL}; (Arena){.begin = region, .end = region, .child = NULL, .sibling = NULL};
// if parent has no children this arena is now it's child // if parent has no children this arena is now it's child
if (parent->child == NULL) { if (parent->child == NULL) {
@ -66,6 +66,8 @@ void arena_deinit(Arena *arena) {
} }
void *arena_alloc(Arena *arena, size_t size) { void *arena_alloc(Arena *arena, size_t size) {
// TODO: only align when needed
size = (size + 7) & ~7; // align size increase to multiple of 8
Region *region = arena->end; Region *region = arena->end;
assert(region != NULL); assert(region != NULL);

View file

@ -13,14 +13,14 @@
int main(int argc, char *argv[]) { int main(int argc, char *argv[]) {
// arena allocation test // arena allocation test
printf("Allocation test"); printf("Allocation test\n");
Arena global_arena = arena_init(NULL, 0); Arena global_arena = arena_init(NULL, 0);
for (int i = 0; i <= 1048576+100; i++) { for (int i = 0; i <= 1048576+100; i++) {
int *number = arena_alloc(&global_arena, sizeof(int)); int *number = arena_alloc(&global_arena, sizeof(int));
*number = 42; *number = 42;
} }
printf("children test"); printf("children test\n");
// arena children test // arena children test
Arena child_arena = arena_init(&global_arena, 0); Arena child_arena = arena_init(&global_arena, 0);
@ -29,6 +29,7 @@ int main(int argc, char *argv[]) {
arena_deinit(&global_arena); arena_deinit(&global_arena);
printf("tests complete\n");
} }