cameron
/
cs241-project
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
Browse Source

Thick refactor in attempt to fix things

tree_alloc
Cameron Weinfurt 2 years ago
parent
748cd262c3
commit
ac2bc19ef1
2 changed files with 406 additions and 399 deletions
Whitespace
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Split View
Diff Options
Show Stats Download Patch File Download Diff File
  1. 1
      Makefile
  2. 804
      tree_alloc.c

1
Makefile
View File

@ -6,6 +6,7 @@ OUT_NAME = the_alloc
dev: CFLAGS= $(COMMON_FLAGS) -g -D UNIT_TESTS -D DEBUG=1
dev: $(OUT_NAME)
rm -f vgcore.*
valgrind ./$(OUT_NAME)
release: CFLAGS= $(COMMON_FLAGS) -O2

804
tree_alloc.c
View File

@ -8,28 +8,28 @@
#include <stdio.h>
int debug_tree_black_height(TreeAlloc *node) {
if (node == NULL) {
return 1;
}
return ((node->color == COLOR_BLACK) ? 1 : 0) + debug_tree_black_height(node->left);
if (node == NULL) {
return 1;
}
return ((node->color == COLOR_BLACK) ? 1 : 0) + debug_tree_black_height(node->left);
}
void debug_print_tree(int indent, void *p) {
TreeAlloc *node = (TreeAlloc*) p;
if (node != NULL) {
int bad = debug_tree_black_height(node->left) != debug_tree_black_height(node->right);
bad |= node->color == COLOR_RED && ((node->left != NULL && node->left->color == COLOR_RED) ||
(node->right != NULL && node->right->color == COLOR_RED) || (node->parent != NULL &&
node->parent->color == COLOR_RED));
debug_print_tree(indent + 1, node->left);
for (int ii = 0; ii < indent; ii++) { printf(" "); }
if (node->color == COLOR_RED) { printf(bad ? "\e[30m]" : "\e[31m"); }
if (bad) { printf("\e[43m"); }
printf("%p %lu\n", node, node->size);
if (node->color == COLOR_RED) { printf("\e[37m"); }
if (bad) { printf("\e[40m"); }
debug_print_tree(indent + 1, node->right);
}
TreeAlloc *node = (TreeAlloc*) p;
if (node != NULL) {
int bad = debug_tree_black_height(node->left) != debug_tree_black_height(node->right);
bad |= node->color == COLOR_RED && ((node->left != NULL && node->left->color == COLOR_RED) ||
(node->right != NULL && node->right->color == COLOR_RED) || (node->parent != NULL &&
node->parent->color == COLOR_RED));
debug_print_tree(indent + 1, node->left);
for (int ii = 0; ii < indent; ii++) { printf(" "); }
if (node->color == COLOR_RED) { printf(bad ? "\e[30m]" : "\e[31m"); }
if (bad) { printf("\e[43m"); }
printf("%p %lu\n", node, node->size);
if (node->color == COLOR_RED) { printf("\e[37m"); }
if (bad) { printf("\e[40m"); }
debug_print_tree(indent + 1, node->right);
}
}
#endif
@ -42,26 +42,26 @@ TreeAlloc *insert_node_at(void *address, uintptr_t padding, uintptr_t align, uin
* Search for the node whose allocated region contains an address.
*/
TreeAlloc *search_by_address(TreeAlloc *root, void *address) {
TreeAlloc *head = root;
while (1) {
if (head > (TreeAlloc*) address) {
if (head->left == NULL) {
return NULL;
} else {
head = head->left;
}
} else {
if (head->right == NULL || head->right > (TreeAlloc*) address) {
return head;
} else {
head = head->right;
}
}
}
TreeAlloc *head = root;
while (1) {
if (head > (TreeAlloc*) address) {
if (head->left == NULL) {
return NULL;
} else {
head = head->left;
}
} else {
if (head->right == NULL || head->right > (TreeAlloc*) address) {
return head;
} else {
head = head->right;
}
}
}
}
static uintptr_t effective_size(TreeAlloc *head, uintptr_t padding, uintptr_t align) {
return head->size - (align_after(head + padding, align) - (void*) head);
return head->size - (align_after(head + padding, align) - (void*) head);
}
/*
@ -70,55 +70,55 @@ static uintptr_t effective_size(TreeAlloc *head, uintptr_t padding, uintptr_t al
* ordering.
*/
static uintptr_t pessimistic_size(TreeAlloc *head, uintptr_t padding, uintptr_t align) {
return head->size - padding - align + 1;
return head->size - padding - align + 1;
}
TreeAlloc *search_by_size(TreeAlloc *root, uintptr_t padding, uintptr_t align, uintptr_t size) {
TreeAlloc *head = root;
while (1) {
uintptr_t esize = pessimistic_size(head, padding, align);
if (esize < size) {
if (head->right == NULL) {
return NULL;
} else {
head = head->right;
}
} else {
if (head->left == NULL || pessimistic_size(head->left, padding, align) < size) {
return head;
} else {
head = head->left;
}
}
}
TreeAlloc *head = root;
while (1) {
uintptr_t esize = pessimistic_size(head, padding, align);
if (esize < size) {
if (head->right == NULL) {
return NULL;
} else {
head = head->right;
}
} else {
if (head->left == NULL || pessimistic_size(head->left, padding, align) < size) {
return head;
} else {
head = head->left;
}
}
}
}
TreeAlloc *succ(TreeAlloc *el) {
if (el->right != NULL) {
el = el->right;
while (el->left != NULL) {
el = el->left;
}
return el;
}
while (el->parent != NULL && el == el->parent->right) {
el = el->parent;
}
return el->parent;
if (el->right != NULL) {
el = el->right;
while (el->left != NULL) {
el = el->left;
}
return el;
}
while (el->parent != NULL && el == el->parent->right) {
el = el->parent;
}
return el->parent;
}
TreeAlloc *pred(TreeAlloc *el) {
if (el->left != NULL) {
el = el->left;
while (el->right != NULL) {
el = el->right;
}
return el;
}
while (el->parent != NULL && el == el->parent->left) {
el = el->parent;
}
return el->parent;
if (el->left != NULL) {
el = el->left;
while (el->right != NULL) {
el = el->right;
}
return el;
}
while (el->parent != NULL && el == el->parent->left) {
el = el->parent;
}
return el->parent;
}
TreeAlloc *get_sibling(TreeAlloc *ta) {
@ -132,51 +132,47 @@ TreeAlloc *get_sibling(TreeAlloc *ta) {
}
void rotate_left(TreeAlloc **root_ptr, TreeAlloc *ta) {
TreeAlloc *parent, *tmp;
parent = ta->parent;
tmp = ta->right;
if (!tmp) return;
ta->right = tmp->left;
tmp->left = ta;
ta->parent = tmp;
if (ta->right) ta->right->parent = ta;
if (parent == NULL) {
*root_ptr = tmp;
} else {
if (ta == parent->left)
parent->left = tmp;
else
parent->right = tmp;
}
tmp->parent = parent;
TreeAlloc *parent, *tmp;
tmp = ta->right;
parent = ta->parent;
ta->right = tmp->left;
if (ta->right) ta->right->parent = ta;
tmp->left = ta;
ta->parent = tmp;
tmp->parent = parent;
if (!parent) {
*root_ptr = tmp;
} else if (ta == parent->left) {
parent->left = tmp;
} else {
parent->right = tmp;
}
}
void rotate_right(TreeAlloc **root_ptr, TreeAlloc *ta) {
TreeAlloc *parent, *tmp;
parent = ta->parent;
tmp = ta->left;
if (!tmp) return;
ta->left = tmp->right;
tmp->right = ta;
ta->parent = tmp;
if (ta->left) ta->left->parent = ta;
if (parent == NULL) {
*root_ptr = tmp;
} else {
if (ta == parent->left)
parent->left = tmp;
else
parent->right = tmp;
}
tmp->parent = parent;
TreeAlloc *parent, *tmp;
tmp = ta->left;
parent = ta->parent;
ta->left = tmp->right;
if (ta->left) ta->left->parent = ta;
tmp->right = ta;
ta->parent = tmp;
tmp->parent = parent;
if (!parent) {
*root_ptr = tmp;
} else if (ta == parent->left) {
parent->left = tmp;
} else {
parent->right = tmp;
}
}
#define IS_BLACK_NODE(n) (n == NULL || n->color == COLOR_BLACK)
@ -185,51 +181,115 @@ void rotate_right(TreeAlloc **root_ptr, TreeAlloc *ta) {
void repair_tree_after_insert(TreeAlloc **root_ptr, TreeAlloc *ta) {
TreeAlloc *parent = ta->parent;
#ifdef DEBUG
printf("=== PRE-INSERT-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
printf("=== PRE-INSERT-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
if (parent == NULL) {
if (ta == *root_ptr) {
ta->color = COLOR_BLACK;
} else if (IS_BLACK_NODE(parent)) {
return;
}
TreeAlloc *grandparent = parent->parent;
TreeAlloc *uncle = get_sibling(parent);
} else {
TreeAlloc *uncle = get_sibling(parent);
TreeAlloc *grandparent = parent->parent;
if (IS_RED_NODE(parent)) {
if (IS_RED_NODE(uncle)) {
parent->color = COLOR_BLACK;
uncle->color = COLOR_BLACK;
grandparent->color = COLOR_RED;
grandparent->color = COLOR_RED;
repair_tree_after_insert(root_ptr, grandparent);
} else {
if (ta == parent->left && parent == grandparent->left) {
rotate_left(root_ptr, parent);
ta = ta->left;
parent = parent->left;
if (parent->left == ta) {
if (grandparent->left == parent) {
rotate_right(root_ptr, grandparent);
grandparent->color = COLOR_RED;
parent->color = COLOR_BLACK;
} else {
rotate_right(root_ptr, parent);
rotate_left(root_ptr, grandparent);
grandparent->color = COLOR_RED;
ta->color = COLOR_BLACK;
}
} else {
rotate_right(root_ptr, parent);
ta = ta->right;
parent = parent->right;
if (grandparent->left == parent) {
rotate_left(root_ptr, parent);
rotate_right(root_ptr, grandparent);
grandparent->color = COLOR_RED;
ta->color = COLOR_BLACK;
} else {
rotate_left(root_ptr, grandparent);
grandparent->color = COLOR_RED;
parent->color = COLOR_BLACK;
}
}
grandparent = parent->parent;
if (ta == parent->left) {
rotate_right(root_ptr, grandparent);
} else {
rotate_left(root_ptr, grandparent);
}
parent->color = COLOR_BLACK;
grandparent->color = COLOR_RED;
}
}
}
// Inserts a node into an empty tree.
void insert_singleton(TreeAlloc **root_ptr, TreeAlloc *to_insert) {
#ifdef DEBUG
printf("= PRE-INSERT-SINGLETON =\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
*root_ptr = to_insert;
to_insert->parent = NULL;
to_insert->color = COLOR_BLACK;
#ifdef DEBUG
printf("= POST-INSERT-SINGLETON =\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
}
void insert_right(TreeAlloc** root_ptr, TreeAlloc* to_insert, TreeAlloc* after) {
#ifdef DEBUG
printf("=== PRE-INSERT-RIGHT ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
if (after->right != NULL) {
after->right->parent = to_insert;
to_insert->right = after->right;
}
after->right = to_insert;
to_insert->parent = after;
to_insert->color = COLOR_RED;
repair_tree_after_insert(root_ptr, to_insert);
#ifdef DEBUG
printf("== POST-INSERT-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
}
void insert_left(TreeAlloc** root_ptr, TreeAlloc* to_insert, TreeAlloc* before) {
#ifdef DEBUG
printf("=== PRE-INSERT-LEFT ====\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
if (before->left != NULL) {
before->left->parent = to_insert;
to_insert->left = before->left;
}
before->left = to_insert;
to_insert->parent = before;
to_insert->color = COLOR_RED;
repair_tree_after_insert(root_ptr, to_insert);
#ifdef DEBUG
printf("== POST-INSERT-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
printf("== POST-INSERT-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
}
@ -291,10 +351,10 @@ void repair_after_remove(TreeAlloc **root_ptr, TreeAlloc *node) {
void remove_node(TreeAlloc **root_ptr, TreeAlloc *node) {
char do_repair = 0;
#ifdef DEBUG
printf("====== PRE-REMOVE ======\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
printf("====== PRE-REMOVE ======\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
TreeAlloc *replace;
TreeAlloc *parent = node->parent;
@ -322,295 +382,241 @@ void remove_node(TreeAlloc **root_ptr, TreeAlloc *node) {
node->left->parent = tmp;
}
// Make sure that it doesn't have any tree pointers it shouldn't have.
node->parent = node->left = node->right = NULL;
// Make sure that it doesn't have any tree pointers it shouldn't have.
node->parent = node->left = node->right = NULL;
if (replace && replace->parent == NULL) {
#ifdef DEBUG
printf("=== PRE-REMOVE-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
printf("=== PRE-REMOVE-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
replace->color = COLOR_BLACK;
replace->color = COLOR_BLACK;
} else if (do_repair && replace) {
#ifdef DEBUG
printf("=== PRE-REMOVE-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
printf("=== PRE-REMOVE-FIXUP ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
repair_after_remove(root_ptr, replace);
}
#ifdef DEBUG
printf("=== POST-REMOVE ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
}
// Inserts a node into an empty tree.
void insert_singleton(TreeAlloc **root_ptr, TreeAlloc *to_insert) {
#ifdef DEBUG
printf("= PRE-INSERT-SINGLETON =\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
*root_ptr = to_insert;
to_insert->parent = NULL;
to_insert->color = COLOR_BLACK;
#ifdef DEBUG
printf("= POST-INSERT-SINGLETON =\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
}
void insert_right(TreeAlloc** root_ptr, TreeAlloc* to_insert, TreeAlloc* after) {
#ifdef DEBUG
printf("=== PRE-INSERT-RIGHT ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
printf("=== POST-REMOVE ===\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
if (after->right != NULL) {
after->right->parent = to_insert;
to_insert->right = after->right;
}
after->right = to_insert;
to_insert->parent = after;
to_insert->color = COLOR_RED;
repair_tree_after_insert(root_ptr, to_insert);
}
void insert_left(TreeAlloc** root_ptr, TreeAlloc* to_insert, TreeAlloc* before) {
#ifdef DEBUG
printf("=== PRE-INSERT-LEFT ====\n");
printf("===== CURRENT TREE =====\n");
debug_print_tree(0, *root_ptr);
printf("===== END OF TREES =====\n");
#endif
if (before->left != NULL) {
before->left->parent = to_insert;
to_insert->left = before->left;
}
before->left = to_insert;
to_insert->parent = before;
to_insert->color = COLOR_RED;
repair_tree_after_insert(root_ptr, to_insert);
}
int add_new_region(Arena *arena, uintptr_t size, uintptr_t padding, uintptr_t align) {
uintptr_t realsize = size + align + alignof(WatermarkAlloc) + padding - 1;
if (realsize < MIN_NEW_MEM_SIZE) {
realsize = MIN_NEW_MEM_SIZE;
}
FreeSpace *reg = (FreeSpace*) arena->get_new_region(realsize);
if (reg == NULL) {
arena->error("can't allocate a new memory region!");
return 0;
}
FreeSpace *newreg = align_after(reg, alignof(WatermarkAlloc));
newreg->left = NULL;
newreg->right = NULL;
realsize -= (void*) newreg - (void*) reg;
realsize -= realsize % alignof(WatermarkAlloc);
newreg->size = realsize;
if (arena->root_freespace == NULL) {
insert_singleton((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) newreg);
} else {
FreeSpace *head = arena->root_freespace;
while (head->right != NULL) {
head = head->right;
}
insert_right((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) newreg, (TreeAlloc*) head);
}
uintptr_t realsize = size + align + alignof(WatermarkAlloc) + padding - 1;
if (realsize < MIN_NEW_MEM_SIZE) {
realsize = MIN_NEW_MEM_SIZE;
}
FreeSpace *reg = (FreeSpace*) arena->get_new_region(realsize);
if (reg == NULL) {
arena->error("can't allocate a new memory region!");
return 0;
}
FreeSpace *newreg = align_after(reg, alignof(WatermarkAlloc));
newreg->left = NULL;
newreg->right = NULL;
realsize -= (void*) newreg - (void*) reg;
realsize -= realsize % alignof(WatermarkAlloc);
newreg->size = realsize;
if (arena->root_freespace == NULL) {
insert_singleton((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) newreg);
} else {
FreeSpace *head = arena->root_freespace;
while (head->right != NULL) {
head = head->right;
}
insert_right((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) newreg, (TreeAlloc*) head);
}
#ifdef DEBUG
printf("= POST-REGION-CREATION =\n");
printf("==== FREESPACE TREE ====\n");
debug_print_tree(0, arena->root_freespace);
printf("==== TREEALLOC TREE ====\n");
debug_print_tree(0, arena->root_treealloc);
printf("===== END OF TREES =====\n");
printf("= POST-REGION-CREATION =\n");
printf("==== FREESPACE TREE ====\n");
debug_print_tree(0, arena->root_freespace);
printf("==== TREEALLOC TREE ====\n");
debug_print_tree(0, arena->root_treealloc);
printf("===== END OF TREES =====\n");
#endif
return 1;
return 1;
}
void unalloc(Arena *arena, void *addr) {
#ifdef DEBUG
printf("==== UNALLOCATING ====\n");
printf("=== FREESPACE TREE ===\n");
debug_print_tree(0, arena->root_freespace);
printf("=== TREEALLOC TREE ===\n");
debug_print_tree(0, arena->root_treealloc);
printf("==== END OF TREES ====\n");
printf("==== UNALLOCATING ====\n");
printf("=== FREESPACE TREE ===\n");
debug_print_tree(0, arena->root_freespace);
printf("=== TREEALLOC TREE ===\n");
debug_print_tree(0, arena->root_treealloc);
printf("==== END OF TREES ====\n");
#endif
if (arena->root_treealloc == NULL) {
arena->error("attempt to unallocate when there are no allocations!");
return;
}
// Find the node this address belongs to
TreeAlloc *node = search_by_address(arena->root_treealloc, addr);
if (node == NULL) {
arena->error("attempt to free memory outside any allocations!");
return;
}
// Handle the watermark allocator in this region
if (node->type == RT_WATERMARK) {
// TODO: handle watermark deallocation
return;
}
// Get rid of it
remove_node(&arena->root_treealloc, node);
// If there's free space on either side of it, merge it with the free space into a bigger chunk of
// free space.
uintptr_t size = node->size;
FreeSpace *start = (FreeSpace*) node;
if (node->before != NULL && node->before->type == RT_FREESPACE) {
start = (FreeSpace*) node->before;
size += node->before->size;
remove_node((TreeAlloc**) &arena->root_freespace, node->before);
}
if (node->after != NULL && node->after->type == RT_FREESPACE) {
size += node->after->size;
remove_node((TreeAlloc**) &arena->root_freespace, node->after);
}
start->type = RT_FREESPACE;
start->size = size;
// And finally, insert the resulting free space.
if (arena->root_freespace == NULL) {
insert_singleton((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) start);
} else {
TreeAlloc *insert_point = search_by_size((TreeAlloc*) arena->root_freespace, 0, 1, size);
if (insert_point == NULL) {
TreeAlloc *head = (TreeAlloc*) arena->root_freespace;
while (head->right != NULL) {
head = head->right;
}
insert_right((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) start, head);
} else {
insert_left((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) start, insert_point);
}
}
if (arena->root_treealloc == NULL) {
arena->error("attempt to unallocate when there are no allocations!");
return;
}
// Find the node this address belongs to
TreeAlloc *node = search_by_address(arena->root_treealloc, addr);
if (node == NULL) {
arena->error("attempt to free memory outside any allocations!");
return;
}
// Handle the watermark allocator in this region
if (node->type == RT_WATERMARK) {
// TODO: handle watermark deallocation
return;
}
// Get rid of it
remove_node(&arena->root_treealloc, node);
// If there's free space on either side of it, merge it with the free space into a bigger chunk of
// free space.
uintptr_t size = node->size;
FreeSpace *start = (FreeSpace*) node;
if (node->before != NULL && node->before->type == RT_FREESPACE) {
start = (FreeSpace*) node->before;
size += node->before->size;
remove_node((TreeAlloc**) &arena->root_freespace, node->before);
}
if (node->after != NULL && node->after->type == RT_FREESPACE) {
size += node->after->size;
remove_node((TreeAlloc**) &arena->root_freespace, node->after);
}
start->type = RT_FREESPACE;
start->size = size;
// And finally, insert the resulting free space.
if (arena->root_freespace == NULL) {
insert_singleton((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) start);
} else {
TreeAlloc *insert_point = search_by_size((TreeAlloc*) arena->root_freespace, 0, 1, size);
if (insert_point == NULL) {
TreeAlloc *head = (TreeAlloc*) arena->root_freespace;
while (head->right != NULL) {
head = head->right;
}
insert_right((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) start, head);
} else {
insert_left((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) start, insert_point);
}
}
}
void *alloc(Arena *arena, uintptr_t size, uintptr_t align) {
uintptr_t actual_align = lcm(alignof(struct WatermarkAlloc), align);
uintptr_t actual_align = lcm(alignof(struct WatermarkAlloc), align);
#ifdef DEBUG
printf("==== ALLOCATING =====\n");
printf("=== FREESPACE TREE ===\n");
debug_print_tree(0, arena->root_freespace);
printf("=== TREEALLOC TREE ===\n");
debug_print_tree(0, arena->root_treealloc);
printf("==== END OF TREES ====\n");
printf("==== ALLOCATING =====\n");
printf("=== FREESPACE TREE ===\n");
debug_print_tree(0, arena->root_freespace);
printf("=== TREEALLOC TREE ===\n");
debug_print_tree(0, arena->root_treealloc);
printf("==== END OF TREES ====\n");
#endif
if (arena->root_freespace == NULL) {
// Handle being out of freespace.
if (arena->root_freespace == NULL) {
// Handle being out of freespace.
#ifdef DEBUG
printf("Out of freespace nodes; getting more\n");
printf("Out of freespace nodes; getting more\n");
#endif
if (!add_new_region(arena, size, sizeof(TreeAlloc), actual_align)) {
return NULL;
}
return alloc(arena, size, align);
} else {
TreeAlloc *region = search_by_size((TreeAlloc*) arena->root_freespace, sizeof(TreeAlloc), actual_align, size);
if (region == NULL) {
// Handle insufficient freespace or fragmentation.
if (!add_new_region(arena, size, sizeof(TreeAlloc), actual_align)) {
return NULL;
}
return alloc(arena, size, align);
} else {
TreeAlloc *region = search_by_size((TreeAlloc*) arena->root_freespace, sizeof(TreeAlloc), actual_align, size);
if (region == NULL) {
// Handle insufficient freespace or fragmentation.
#ifdef DEBUG
printf("Out of sufficiently large freespace nodes; getting more\n");
printf("Out of sufficiently large freespace nodes; getting more\n");
#endif
if (!add_new_region(arena, size, sizeof(TreeAlloc), actual_align)) {
return NULL;
}
return alloc(arena, size, align);
}
remove_node((TreeAlloc**) &arena->root_freespace, region);
void *true_end = align_after(align_after(((void*) region) + sizeof(TreeAlloc), actual_align) + size, alignof(WatermarkAlloc));
// The size of the new allocation (adjusted for region header and alignment
uintptr_t new_size = true_end - (void*) region;
// The size of the free space region following the new allocation
uintptr_t new_free_size = region->size - new_size;
region->right = NULL;
region->left = NULL;
region->type = RT_TREE_NODE;
if (!add_new_region(arena, size, sizeof(TreeAlloc), actual_align)) {
return NULL;
}
return alloc(arena, size, align);
}
remove_node((TreeAlloc**) &arena->root_freespace, region);
void *true_end = align_after(align_after(((void*) region) + sizeof(TreeAlloc), actual_align) + size, alignof(WatermarkAlloc));
// The size of the new allocation (adjusted for region header and alignment
uintptr_t new_size = true_end - (void*) region;
// The size of the free space region following the new allocation
uintptr_t new_free_size = region->size - new_size;
region->right = NULL;
region->left = NULL;
region->type = RT_TREE_NODE;
#ifdef DEBUG
printf("start: %p, end: %p, adjusted end: %p\n", region, ((void*) region) + size, true_end);
printf("size: %lu -> %lu\n", size, new_size);
printf("start: %p, end: %p, adjusted end: %p\n", region, ((void*) region) + size, true_end);
printf("size: %lu -> %lu\n", size, new_size);
#endif
if (arena->root_treealloc == NULL) {
insert_singleton((TreeAlloc**) &arena->root_treealloc, region);
} else {
if (arena->root_treealloc == NULL) {
insert_singleton((TreeAlloc**) &arena->root_treealloc, region);
} else {
#ifdef DEBUG
printf("searching for an insert point\n");
printf("searching for an insert point\n");
#endif
TreeAlloc *insert_point = search_by_address((TreeAlloc*) arena->root_treealloc, region);
if (insert_point == NULL) {
TreeAlloc *head = arena->root_treealloc;
while (head->left != NULL) {
head = head->left;
}
TreeAlloc *insert_point = search_by_address((TreeAlloc*) arena->root_treealloc, region);
if (insert_point == NULL) {
TreeAlloc *head = arena->root_treealloc;
while (head->left != NULL) {
head = head->left;
}
#ifdef DEBUG
printf("none found; inserting before %p\n", head);
printf("none found; inserting before %p\n", head);
#endif
insert_left(&arena->root_treealloc, region, head);
} else {
insert_left(&arena->root_treealloc, region, head);
} else {
#ifdef DEBUG
printf("found one: %p\n", insert_point);
printf("found one: %p\n", insert_point);
#endif
insert_right(&arena->root_treealloc, region, insert_point);
}
}
if (new_free_size >= sizeof(FreeSpace)) {
// If there's enough free space after the allocation, use it!
region->size = new_size; // Safe because the allocated region tree is not sorted by size.
FreeSpace *new_free = (FreeSpace*) ((void*) region + new_size);
new_free->left = NULL;
new_free->right = NULL;
new_free->type = RT_FREESPACE;
new_free->size = new_free_size;
if (arena->root_freespace == NULL) {
insert_singleton((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) new_free);
} else {
FreeSpace *insert_point = (FreeSpace*) search_by_size((TreeAlloc*) arena->root_freespace, 0, 1, new_free_size);
insert_left((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) new_free, (TreeAlloc*) insert_point);
}
// Set the region following this one to be the new free space
region->after = (TreeAlloc*) new_free;
} else {
// There isn't a free space after this one, so put the `next` pointer at the next allocated
// region.
region->after = succ(region);
}
// I seem to have forgotten about the fact that memory may not be contiguous
if (region->after != NULL && region->after != (void*) region + region->size) {
region->after = NULL;
}
// Also make sure the `before` pointer is correct.
TreeAlloc *before_alloc = pred(region);
if (before_alloc == NULL || ((void*) before_alloc) + before_alloc->size < (void*) region) {
region->before = search_by_address((TreeAlloc*) arena->root_freespace, region);
} else {
region->before = before_alloc;
}
// I seem to have forgotten about the fact that memory may not be contiguous
if (region->before != NULL && region->before != (void*) region->before + region->before->size) {
region->before = NULL;
}
insert_right(&arena->root_treealloc, region, insert_point);
}
}
if (new_free_size >= sizeof(FreeSpace)) {
// If there's enough free space after the allocation, use it!
region->size = new_size; // Safe because the allocated region tree is not sorted by size.
FreeSpace *new_free = (FreeSpace*) ((void*) region + new_size);
new_free->left = NULL;
new_free->right = NULL;
new_free->type = RT_FREESPACE;
new_free->size = new_free_size;
if (arena->root_freespace == NULL) {
insert_singleton((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) new_free);
} else {
FreeSpace *insert_point = (FreeSpace*) search_by_size((TreeAlloc*) arena->root_freespace, 0, 1, new_free_size);
insert_left((TreeAlloc**) &arena->root_freespace, (TreeAlloc*) new_free, (TreeAlloc*) insert_point);
}
// Set the region following this one to be the new free space
region->after = (TreeAlloc*) new_free;
} else {
// There isn't a free space after this one, so put the `next` pointer at the next allocated
// region.
region->after = succ(region);
}
// I seem to have forgotten about the fact that memory may not be contiguous
if (region->after != NULL && region->after != (void*) region + region->size) {
region->after = NULL;
}
// Also make sure the `before` pointer is correct.
TreeAlloc *before_alloc = pred(region);
if (before_alloc == NULL || ((void*) before_alloc) + before_alloc->size < (void*) region) {
region->before = search_by_address((TreeAlloc*) arena->root_freespace, region);
} else {
region->before = before_alloc;
}
// I seem to have forgotten about the fact that memory may not be contiguous
if (region->before != NULL && region->before != (void*) region->before + region->before->size) {
region->before = NULL;
}
#ifdef DEBUG
printf("region is still at %p\n", region);
printf("region is still at %p\n", region);
#endif
return align_after((void*) region + sizeof(TreeAlloc), actual_align);
}
return align_after((void*) region + sizeof(TreeAlloc), actual_align);
}
}
void *alloc_growable(Arena *arena, uintptr_t size, uintptr_t align) {
// TODO: Basically the same as above, but put the allocated region in the center of the largest free
// space. Due to alignment and whatnot, the code will be gory.
return NULL;
// TODO: Basically the same as above, but put the allocated region in the center of the largest free
// space. Due to alignment and whatnot, the code will be gory.
return NULL;
}
Write Preview
Loading…
Cancel
Save