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authorOri Bernstein <ori@eigenstate.org>2021-06-14 00:00:37 +0000
committerOri Bernstein <ori@eigenstate.org>2021-06-14 00:00:37 +0000
commita73a964e51247ed169d322c725a3a18859f109a3 (patch)
tree3f752d117274d444bda44e85609aeac1acf313f3 /sys/src/cmd/python/Python/pyarena.c
parente64efe273fcb921a61bf27d33b230c4e64fcd425 (diff)
python, hg: tow outside the environment.
they've served us well, and can ride off into the sunset.
Diffstat (limited to 'sys/src/cmd/python/Python/pyarena.c')
-rw-r--r--sys/src/cmd/python/Python/pyarena.c220
1 files changed, 0 insertions, 220 deletions
diff --git a/sys/src/cmd/python/Python/pyarena.c b/sys/src/cmd/python/Python/pyarena.c
deleted file mode 100644
index f4cc474f4..000000000
--- a/sys/src/cmd/python/Python/pyarena.c
+++ /dev/null
@@ -1,220 +0,0 @@
-#include "Python.h"
-#include "pyarena.h"
-
-/* A simple arena block structure.
-
- Measurements with standard library modules suggest the average
- allocation is about 20 bytes and that most compiles use a single
- block.
-
- TODO(jhylton): Think about a realloc API, maybe just for the last
- allocation?
-*/
-
-#define DEFAULT_BLOCK_SIZE 8192
-#define ALIGNMENT 8
-#define ALIGNMENT_MASK (ALIGNMENT - 1)
-#define ROUNDUP(x) (((x) + ALIGNMENT_MASK) & ~ALIGNMENT_MASK)
-
-typedef struct _block {
- /* Total number of bytes owned by this block available to pass out.
- * Read-only after initialization. The first such byte starts at
- * ab_mem.
- */
- size_t ab_size;
-
- /* Total number of bytes already passed out. The next byte available
- * to pass out starts at ab_mem + ab_offset.
- */
- size_t ab_offset;
-
- /* An arena maintains a singly-linked, NULL-terminated list of
- * all blocks owned by the arena. These are linked via the
- * ab_next member.
- */
- struct _block *ab_next;
-
- /* Pointer to the first allocatable byte owned by this block. Read-
- * only after initialization.
- */
- void *ab_mem;
-} block;
-
-/* The arena manages two kinds of memory, blocks of raw memory
- and a list of PyObject* pointers. PyObjects are decrefed
- when the arena is freed.
-*/
-
-struct _arena {
- /* Pointer to the first block allocated for the arena, never NULL.
- It is used only to find the first block when the arena is
- being freed.
- */
- block *a_head;
-
- /* Pointer to the block currently used for allocation. It's
- ab_next field should be NULL. If it is not-null after a
- call to block_alloc(), it means a new block has been allocated
- and a_cur should be reset to point it.
- */
- block *a_cur;
-
- /* A Python list object containing references to all the PyObject
- pointers associated with this area. They will be DECREFed
- when the arena is freed.
- */
- PyObject *a_objects;
-
-#if defined(Py_DEBUG)
- /* Debug output */
- size_t total_allocs;
- size_t total_size;
- size_t total_blocks;
- size_t total_block_size;
- size_t total_big_blocks;
-#endif
-};
-
-static block *
-block_new(size_t size)
-{
- /* Allocate header and block as one unit.
- ab_mem points just past header. */
- block *b = (block *)malloc(sizeof(block) + size);
- if (!b)
- return NULL;
- b->ab_size = size;
- b->ab_mem = (void *)(b + 1);
- b->ab_next = NULL;
- b->ab_offset = ROUNDUP((Py_uintptr_t)(b->ab_mem)) -
- (Py_uintptr_t)(b->ab_mem);
- return b;
-}
-
-static void
-block_free(block *b) {
- while (b) {
- block *next = b->ab_next;
- free(b);
- b = next;
- }
-}
-
-static void *
-block_alloc(block *b, size_t size)
-{
- void *p;
- assert(b);
- size = ROUNDUP(size);
- if (b->ab_offset + size > b->ab_size) {
- /* If we need to allocate more memory than will fit in
- the default block, allocate a one-off block that is
- exactly the right size. */
- /* TODO(jhylton): Think about space waste at end of block */
- block *newbl = block_new(
- size < DEFAULT_BLOCK_SIZE ?
- DEFAULT_BLOCK_SIZE : size);
- if (!newbl)
- return NULL;
- assert(!b->ab_next);
- b->ab_next = newbl;
- b = newbl;
- }
-
- assert(b->ab_offset + size <= b->ab_size);
- p = (void *)(((char *)b->ab_mem) + b->ab_offset);
- b->ab_offset += size;
- return p;
-}
-
-PyArena *
-PyArena_New()
-{
- PyArena* arena = (PyArena *)malloc(sizeof(PyArena));
- if (!arena)
- return (PyArena*)PyErr_NoMemory();
-
- arena->a_head = block_new(DEFAULT_BLOCK_SIZE);
- arena->a_cur = arena->a_head;
- if (!arena->a_head) {
- free((void *)arena);
- return (PyArena*)PyErr_NoMemory();
- }
- arena->a_objects = PyList_New(0);
- if (!arena->a_objects) {
- block_free(arena->a_head);
- free((void *)arena);
- return (PyArena*)PyErr_NoMemory();
- }
-#if defined(Py_DEBUG)
- arena->total_allocs = 0;
- arena->total_size = 0;
- arena->total_blocks = 1;
- arena->total_block_size = DEFAULT_BLOCK_SIZE;
- arena->total_big_blocks = 0;
-#endif
- return arena;
-}
-
-void
-PyArena_Free(PyArena *arena)
-{
- int r;
- assert(arena);
-#if defined(Py_DEBUG)
- /*
- fprintf(stderr,
- "alloc=%d size=%d blocks=%d block_size=%d big=%d objects=%d\n",
- arena->total_allocs, arena->total_size, arena->total_blocks,
- arena->total_block_size, arena->total_big_blocks,
- PyList_Size(arena->a_objects));
- */
-#endif
- block_free(arena->a_head);
- /* This property normally holds, except when the code being compiled
- is sys.getobjects(0), in which case there will be two references.
- assert(arena->a_objects->ob_refcnt == 1);
- */
-
- /* Clear all the elements from the list. This is necessary
- to guarantee that they will be DECREFed. */
- r = PyList_SetSlice(arena->a_objects,
- 0, PyList_GET_SIZE(arena->a_objects), NULL);
- assert(r == 0);
- assert(PyList_GET_SIZE(arena->a_objects) == 0);
- Py_DECREF(arena->a_objects);
- free(arena);
-}
-
-void *
-PyArena_Malloc(PyArena *arena, size_t size)
-{
- void *p = block_alloc(arena->a_cur, size);
- if (!p)
- return PyErr_NoMemory();
-#if defined(Py_DEBUG)
- arena->total_allocs++;
- arena->total_size += size;
-#endif
- /* Reset cur if we allocated a new block. */
- if (arena->a_cur->ab_next) {
- arena->a_cur = arena->a_cur->ab_next;
-#if defined(Py_DEBUG)
- arena->total_blocks++;
- arena->total_block_size += arena->a_cur->ab_size;
- if (arena->a_cur->ab_size > DEFAULT_BLOCK_SIZE)
- ++arena->total_big_blocks;
-#endif
- }
- return p;
-}
-
-int
-PyArena_AddPyObject(PyArena *arena, PyObject *obj)
-{
- int r = PyList_Append(arena->a_objects, obj);
- if (r >= 0) {
- Py_DECREF(obj);
- }
- return r;
-}