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-rw-r--r--sys/base/mem/arena.c119
1 files changed, 0 insertions, 119 deletions
diff --git a/sys/base/mem/arena.c b/sys/base/mem/arena.c
deleted file mode 100644
index b2ce044..0000000
--- a/sys/base/mem/arena.c
+++ /dev/null
@@ -1,119 +0,0 @@
-#include "internal.h"
-
-#define ARENA_ALIGN 8
-#define ARENA_BLOCK_SIZE 1024 * 1024
-
-#define ALIGN_DOWN(n, a) ((n) & ~((a)-1))
-#define ALIGN_UP(n, a) ALIGN_DOWN((n) + (a)-1, (a))
-#define ALIGN_DOWN_PTR(p, a) ((void*)ALIGN_DOWN((uintptr)(p), (a)))
-#define ALIGN_UP_PTR(p, a) ((void*)ALIGN_UP((uintptr)(p), (a)))
-
-struct Block
-{
- struct Block *next;
- byte buf[];
-};
-
-struct mem·Arena
-{
- void *heap;
- mem·Allocator mem;
-
- byte *off;
- byte *end;
- struct Block *curr;
- struct Block first;
-};
-
-static
-void*
-·arenaalloc(void *heap, uint n, ulong size)
-{
- return mem·arenaalloc(heap, n, size);
-}
-
-static
-void
-·arenafree(void *heap, void *ptr)
-{
- /* no-op */
-}
-
-mem·Allocator mem·ArenaAllocator = {
- .alloc = ·arenaalloc,
- .free = ·arenafree,
-};
-
-
-static
-void
-grow(mem·Arena *a, vlong min)
-{
- uintptr size;
- struct Block *blk;
-
- size = ALIGN_UP(MAX(min, ARENA_BLOCK_SIZE), ARENA_ALIGN);
- blk = a->mem.alloc(a->heap, 1, sizeof(*blk) + size);
- a->off = blk->buf;
- a->end = a->off + size;
-
- assert(a->curr->next == nil);
- assert(a->off == ALIGN_DOWN_PTR(a->off, ARENA_ALIGN));
-
- a->curr->next = blk;
- a->curr = blk;
-}
-
-mem·Arena*
-mem·makearena(mem·Allocator from, void *impl)
-{
- mem·Arena *a = from.alloc(impl, 1, sizeof(*a) + ARENA_BLOCK_SIZE);
- a->mem = from;
- a->heap = impl;
- a->off = a->first.buf;
- a->end = a->first.buf + ARENA_BLOCK_SIZE;
- a->curr = &a->first;
- a->first.next = nil;
-
- return a;
-}
-
-void
-mem·freearena(mem·Arena *a)
-{
- struct Block *it, *next;
-
- it = a->first.next;
- while (it != nil) {
- next = it->next;
- a->mem.free(a->heap, it);
- it = next;
- }
-
- a->mem.free(a->heap, a);
-}
-
-void*
-mem·arenaalloc(mem·Arena *a, uint n, ulong size)
-{
- if(!n) {
- return nil;
- }
-
- void *ptr;
- // TODO(nnoll): check for overflow
- size = n * size;
-
- if (size > (ulong)(a->end - a->off)) {
- grow(a, size);
- assert(size <= (uintptr)(a->end - a->off));
- }
-
- ptr = a->off;
- a->off = ALIGN_UP_PTR(a->off + size, ARENA_ALIGN);
-
- assert(a->off <= a->end);
- assert(ptr == ALIGN_DOWN_PTR(ptr, ARENA_ALIGN));
-
- return ptr;
-}