| #include "Python.h" |
| |
| #include "pycore_hamt.h" |
| #include "pycore_object.h" |
| #include "pycore_pystate.h" |
| #include "structmember.h" |
| |
| /* |
| This file provides an implemention of an immutable mapping using the |
| Hash Array Mapped Trie (or HAMT) datastructure. |
| |
| This design allows to have: |
| |
| 1. Efficient copy: immutable mappings can be copied by reference, |
| making it an O(1) operation. |
| |
| 2. Efficient mutations: due to structural sharing, only a portion of |
| the trie needs to be copied when the collection is mutated. The |
| cost of set/delete operations is O(log N). |
| |
| 3. Efficient lookups: O(log N). |
| |
| (where N is number of key/value items in the immutable mapping.) |
| |
| |
| HAMT |
| ==== |
| |
| The core idea of HAMT is that the shape of the trie is encoded into the |
| hashes of keys. |
| |
| Say we want to store a K/V pair in our mapping. First, we calculate the |
| hash of K, let's say it's 19830128, or in binary: |
| |
| 0b1001011101001010101110000 = 19830128 |
| |
| Now let's partition this bit representation of the hash into blocks of |
| 5 bits each: |
| |
| 0b00_00000_10010_11101_00101_01011_10000 = 19830128 |
| (6) (5) (4) (3) (2) (1) |
| |
| Each block of 5 bits represents a number between 0 and 31. So if we have |
| a tree that consists of nodes, each of which is an array of 32 pointers, |
| those 5-bit blocks will encode a position on a single tree level. |
| |
| For example, storing the key K with hash 19830128, results in the following |
| tree structure: |
| |
| (array of 32 pointers) |
| +---+ -- +----+----+----+ -- +----+ |
| root node | 0 | .. | 15 | 16 | 17 | .. | 31 | 0b10000 = 16 (1) |
| (level 1) +---+ -- +----+----+----+ -- +----+ |
| | |
| +---+ -- +----+----+----+ -- +----+ |
| a 2nd level node | 0 | .. | 10 | 11 | 12 | .. | 31 | 0b01011 = 11 (2) |
| +---+ -- +----+----+----+ -- +----+ |
| | |
| +---+ -- +----+----+----+ -- +----+ |
| a 3rd level node | 0 | .. | 04 | 05 | 06 | .. | 31 | 0b00101 = 5 (3) |
| +---+ -- +----+----+----+ -- +----+ |
| | |
| +---+ -- +----+----+----+----+ |
| a 4th level node | 0 | .. | 04 | 29 | 30 | 31 | 0b11101 = 29 (4) |
| +---+ -- +----+----+----+----+ |
| | |
| +---+ -- +----+----+----+ -- +----+ |
| a 5th level node | 0 | .. | 17 | 18 | 19 | .. | 31 | 0b10010 = 18 (5) |
| +---+ -- +----+----+----+ -- +----+ |
| | |
| +--------------+ |
| | |
| +---+ -- +----+----+----+ -- +----+ |
| a 6th level node | 0 | .. | 15 | 16 | 17 | .. | 31 | 0b00000 = 0 (6) |
| +---+ -- +----+----+----+ -- +----+ |
| | |
| V -- our value (or collision) |
| |
| To rehash: for a K/V pair, the hash of K encodes where in the tree V will |
| be stored. |
| |
| To optimize memory footprint and handle hash collisions, our implementation |
| uses three different types of nodes: |
| |
| * A Bitmap node; |
| * An Array node; |
| * A Collision node. |
| |
| Because we implement an immutable dictionary, our nodes are also |
| immutable. Therefore, when we need to modify a node, we copy it, and |
| do that modification to the copy. |
| |
| |
| Array Nodes |
| ----------- |
| |
| These nodes are very simple. Essentially they are arrays of 32 pointers |
| we used to illustrate the high-level idea in the previous section. |
| |
| We use Array nodes only when we need to store more than 16 pointers |
| in a single node. |
| |
| Array nodes do not store key objects or value objects. They are used |
| only as an indirection level - their pointers point to other nodes in |
| the tree. |
| |
| |
| Bitmap Node |
| ----------- |
| |
| Allocating a new 32-pointers array for every node of our tree would be |
| very expensive. Unless we store millions of keys, most of tree nodes would |
| be very sparse. |
| |
| When we have less than 16 elements in a node, we don't want to use the |
| Array node, that would mean that we waste a lot of memory. Instead, |
| we can use bitmap compression and can have just as many pointers |
| as we need! |
| |
| Bitmap nodes consist of two fields: |
| |
| 1. An array of pointers. If a Bitmap node holds N elements, the |
| array will be of N pointers. |
| |
| 2. A 32bit integer -- a bitmap field. If an N-th bit is set in the |
| bitmap, it means that the node has an N-th element. |
| |
| For example, say we need to store a 3 elements sparse array: |
| |
| +---+ -- +---+ -- +----+ -- +----+ |
| | 0 | .. | 4 | .. | 11 | .. | 17 | |
| +---+ -- +---+ -- +----+ -- +----+ |
| | | | |
| o1 o2 o3 |
| |
| We allocate a three-pointer Bitmap node. Its bitmap field will be |
| then set to: |
| |
| 0b_00100_00010_00000_10000 == (1 << 17) | (1 << 11) | (1 << 4) |
| |
| To check if our Bitmap node has an I-th element we can do: |
| |
| bitmap & (1 << I) |
| |
| |
| And here's a formula to calculate a position in our pointer array |
| which would correspond to an I-th element: |
| |
| popcount(bitmap & ((1 << I) - 1)) |
| |
| |
| Let's break it down: |
| |
| * `popcount` is a function that returns a number of bits set to 1; |
| |
| * `((1 << I) - 1)` is a mask to filter the bitmask to contain bits |
| set to the *right* of our bit. |
| |
| |
| So for our 17, 11, and 4 indexes: |
| |
| * bitmap & ((1 << 17) - 1) == 0b100000010000 => 2 bits are set => index is 2. |
| |
| * bitmap & ((1 << 11) - 1) == 0b10000 => 1 bit is set => index is 1. |
| |
| * bitmap & ((1 << 4) - 1) == 0b0 => 0 bits are set => index is 0. |
| |
| |
| To conclude: Bitmap nodes are just like Array nodes -- they can store |
| a number of pointers, but use bitmap compression to eliminate unused |
| pointers. |
| |
| |
| Bitmap nodes have two pointers for each item: |
| |
| +----+----+----+----+ -- +----+----+ |
| | k1 | v1 | k2 | v2 | .. | kN | vN | |
| +----+----+----+----+ -- +----+----+ |
| |
| When kI == NULL, vI points to another tree level. |
| |
| When kI != NULL, the actual key object is stored in kI, and its |
| value is stored in vI. |
| |
| |
| Collision Nodes |
| --------------- |
| |
| Collision nodes are simple arrays of pointers -- two pointers per |
| key/value. When there's a hash collision, say for k1/v1 and k2/v2 |
| we have `hash(k1)==hash(k2)`. Then our collision node will be: |
| |
| +----+----+----+----+ |
| | k1 | v1 | k2 | v2 | |
| +----+----+----+----+ |
| |
| |
| Tree Structure |
| -------------- |
| |
| All nodes are PyObjects. |
| |
| The `PyHamtObject` object has a pointer to the root node (h_root), |
| and has a length field (h_count). |
| |
| High-level functions accept a PyHamtObject object and dispatch to |
| lower-level functions depending on what kind of node h_root points to. |
| |
| |
| Operations |
| ========== |
| |
| There are three fundamental operations on an immutable dictionary: |
| |
| 1. "o.assoc(k, v)" will return a new immutable dictionary, that will be |
| a copy of "o", but with the "k/v" item set. |
| |
| Functions in this file: |
| |
| hamt_node_assoc, hamt_node_bitmap_assoc, |
| hamt_node_array_assoc, hamt_node_collision_assoc |
| |
| `hamt_node_assoc` function accepts a node object, and calls |
| other functions depending on its actual type. |
| |
| 2. "o.find(k)" will lookup key "k" in "o". |
| |
| Functions: |
| |
| hamt_node_find, hamt_node_bitmap_find, |
| hamt_node_array_find, hamt_node_collision_find |
| |
| 3. "o.without(k)" will return a new immutable dictionary, that will be |
| a copy of "o", buth without the "k" key. |
| |
| Functions: |
| |
| hamt_node_without, hamt_node_bitmap_without, |
| hamt_node_array_without, hamt_node_collision_without |
| |
| |
| Further Reading |
| =============== |
| |
| 1. http://blog.higher-order.net/2009/09/08/understanding-clojures-persistenthashmap-deftwice.html |
| |
| 2. http://blog.higher-order.net/2010/08/16/assoc-and-clojures-persistenthashmap-part-ii.html |
| |
| 3. Clojure's PersistentHashMap implementation: |
| https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/PersistentHashMap.java |
| |
| |
| Debug |
| ===== |
| |
| The HAMT datatype is accessible for testing purposes under the |
| `_testcapi` module: |
| |
| >>> from _testcapi import hamt |
| >>> h = hamt() |
| >>> h2 = h.set('a', 2) |
| >>> h3 = h2.set('b', 3) |
| >>> list(h3) |
| ['a', 'b'] |
| |
| When CPython is built in debug mode, a '__dump__()' method is available |
| to introspect the tree: |
| |
| >>> print(h3.__dump__()) |
| HAMT(len=2): |
| BitmapNode(size=4 count=2 bitmap=0b110 id=0x10eb9d9e8): |
| 'a': 2 |
| 'b': 3 |
| */ |
| |
| |
| #define IS_ARRAY_NODE(node) (Py_TYPE(node) == &_PyHamt_ArrayNode_Type) |
| #define IS_BITMAP_NODE(node) (Py_TYPE(node) == &_PyHamt_BitmapNode_Type) |
| #define IS_COLLISION_NODE(node) (Py_TYPE(node) == &_PyHamt_CollisionNode_Type) |
| |
| |
| /* Return type for 'find' (lookup a key) functions. |
| |
| * F_ERROR - an error occurred; |
| * F_NOT_FOUND - the key was not found; |
| * F_FOUND - the key was found. |
| */ |
| typedef enum {F_ERROR, F_NOT_FOUND, F_FOUND} hamt_find_t; |
| |
| |
| /* Return type for 'without' (delete a key) functions. |
| |
| * W_ERROR - an error occurred; |
| * W_NOT_FOUND - the key was not found: there's nothing to delete; |
| * W_EMPTY - the key was found: the node/tree would be empty |
| if the key is deleted; |
| * W_NEWNODE - the key was found: a new node/tree is returned |
| without that key. |
| */ |
| typedef enum {W_ERROR, W_NOT_FOUND, W_EMPTY, W_NEWNODE} hamt_without_t; |
| |
| |
| /* Low-level iterator protocol type. |
| |
| * I_ITEM - a new item has been yielded; |
| * I_END - the whole tree was visited (similar to StopIteration). |
| */ |
| typedef enum {I_ITEM, I_END} hamt_iter_t; |
| |
| |
| #define HAMT_ARRAY_NODE_SIZE 32 |
| |
| |
| typedef struct { |
| PyObject_HEAD |
| PyHamtNode *a_array[HAMT_ARRAY_NODE_SIZE]; |
| Py_ssize_t a_count; |
| } PyHamtNode_Array; |
| |
| |
| typedef struct { |
| PyObject_VAR_HEAD |
| uint32_t b_bitmap; |
| PyObject *b_array[1]; |
| } PyHamtNode_Bitmap; |
| |
| |
| typedef struct { |
| PyObject_VAR_HEAD |
| int32_t c_hash; |
| PyObject *c_array[1]; |
| } PyHamtNode_Collision; |
| |
| |
| static PyHamtNode_Bitmap *_empty_bitmap_node; |
| static PyHamtObject *_empty_hamt; |
| |
| |
| static PyHamtObject * |
| hamt_alloc(void); |
| |
| static PyHamtNode * |
| hamt_node_assoc(PyHamtNode *node, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject *val, int* added_leaf); |
| |
| static hamt_without_t |
| hamt_node_without(PyHamtNode *node, |
| uint32_t shift, int32_t hash, |
| PyObject *key, |
| PyHamtNode **new_node); |
| |
| static hamt_find_t |
| hamt_node_find(PyHamtNode *node, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject **val); |
| |
| #ifdef Py_DEBUG |
| static int |
| hamt_node_dump(PyHamtNode *node, |
| _PyUnicodeWriter *writer, int level); |
| #endif |
| |
| static PyHamtNode * |
| hamt_node_array_new(Py_ssize_t); |
| |
| static PyHamtNode * |
| hamt_node_collision_new(int32_t hash, Py_ssize_t size); |
| |
| static inline Py_ssize_t |
| hamt_node_collision_count(PyHamtNode_Collision *node); |
| |
| |
| #ifdef Py_DEBUG |
| static void |
| _hamt_node_array_validate(void *obj_raw) |
| { |
| PyObject *obj = _PyObject_CAST(obj_raw); |
| assert(IS_ARRAY_NODE(obj)); |
| PyHamtNode_Array *node = (PyHamtNode_Array*)obj; |
| Py_ssize_t i = 0, count = 0; |
| for (; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| if (node->a_array[i] != NULL) { |
| count++; |
| } |
| } |
| assert(count == node->a_count); |
| } |
| |
| #define VALIDATE_ARRAY_NODE(NODE) \ |
| do { _hamt_node_array_validate(NODE); } while (0); |
| #else |
| #define VALIDATE_ARRAY_NODE(NODE) |
| #endif |
| |
| |
| /* Returns -1 on error */ |
| static inline int32_t |
| hamt_hash(PyObject *o) |
| { |
| Py_hash_t hash = PyObject_Hash(o); |
| |
| #if SIZEOF_PY_HASH_T <= 4 |
| return hash; |
| #else |
| if (hash == -1) { |
| /* exception */ |
| return -1; |
| } |
| |
| /* While it's suboptimal to reduce Python's 64 bit hash to |
| 32 bits via XOR, it seems that the resulting hash function |
| is good enough (this is also how Long type is hashed in Java.) |
| Storing 10, 100, 1000 Python strings results in a relatively |
| shallow and uniform tree structure. |
| |
| Please don't change this hashing algorithm, as there are many |
| tests that test some exact tree shape to cover all code paths. |
| */ |
| int32_t xored = (int32_t)(hash & 0xffffffffl) ^ (int32_t)(hash >> 32); |
| return xored == -1 ? -2 : xored; |
| #endif |
| } |
| |
| static inline uint32_t |
| hamt_mask(int32_t hash, uint32_t shift) |
| { |
| return (((uint32_t)hash >> shift) & 0x01f); |
| } |
| |
| static inline uint32_t |
| hamt_bitpos(int32_t hash, uint32_t shift) |
| { |
| return (uint32_t)1 << hamt_mask(hash, shift); |
| } |
| |
| static inline uint32_t |
| hamt_bitcount(uint32_t i) |
| { |
| /* We could use native popcount instruction but that would |
| require to either add configure flags to enable SSE4.2 |
| support or to detect it dynamically. Otherwise, we have |
| a risk of CPython not working properly on older hardware. |
| |
| In practice, there's no observable difference in |
| performance between using a popcount instruction or the |
| following fallback code. |
| |
| The algorithm is copied from: |
| https://graphics.stanford.edu/~seander/bithacks.html |
| */ |
| i = i - ((i >> 1) & 0x55555555); |
| i = (i & 0x33333333) + ((i >> 2) & 0x33333333); |
| return (((i + (i >> 4)) & 0xF0F0F0F) * 0x1010101) >> 24; |
| } |
| |
| static inline uint32_t |
| hamt_bitindex(uint32_t bitmap, uint32_t bit) |
| { |
| return hamt_bitcount(bitmap & (bit - 1)); |
| } |
| |
| |
| /////////////////////////////////// Dump Helpers |
| #ifdef Py_DEBUG |
| |
| static int |
| _hamt_dump_ident(_PyUnicodeWriter *writer, int level) |
| { |
| /* Write `' ' * level` to the `writer` */ |
| PyObject *str = NULL; |
| PyObject *num = NULL; |
| PyObject *res = NULL; |
| int ret = -1; |
| |
| str = PyUnicode_FromString(" "); |
| if (str == NULL) { |
| goto error; |
| } |
| |
| num = PyLong_FromLong((long)level); |
| if (num == NULL) { |
| goto error; |
| } |
| |
| res = PyNumber_Multiply(str, num); |
| if (res == NULL) { |
| goto error; |
| } |
| |
| ret = _PyUnicodeWriter_WriteStr(writer, res); |
| |
| error: |
| Py_XDECREF(res); |
| Py_XDECREF(str); |
| Py_XDECREF(num); |
| return ret; |
| } |
| |
| static int |
| _hamt_dump_format(_PyUnicodeWriter *writer, const char *format, ...) |
| { |
| /* A convenient helper combining _PyUnicodeWriter_WriteStr and |
| PyUnicode_FromFormatV. |
| */ |
| PyObject* msg; |
| int ret; |
| |
| va_list vargs; |
| #ifdef HAVE_STDARG_PROTOTYPES |
| va_start(vargs, format); |
| #else |
| va_start(vargs); |
| #endif |
| msg = PyUnicode_FromFormatV(format, vargs); |
| va_end(vargs); |
| |
| if (msg == NULL) { |
| return -1; |
| } |
| |
| ret = _PyUnicodeWriter_WriteStr(writer, msg); |
| Py_DECREF(msg); |
| return ret; |
| } |
| |
| #endif /* Py_DEBUG */ |
| /////////////////////////////////// Bitmap Node |
| |
| |
| static PyHamtNode * |
| hamt_node_bitmap_new(Py_ssize_t size) |
| { |
| /* Create a new bitmap node of size 'size' */ |
| |
| PyHamtNode_Bitmap *node; |
| Py_ssize_t i; |
| |
| assert(size >= 0); |
| assert(size % 2 == 0); |
| |
| if (size == 0 && _empty_bitmap_node != NULL) { |
| Py_INCREF(_empty_bitmap_node); |
| return (PyHamtNode *)_empty_bitmap_node; |
| } |
| |
| /* No freelist; allocate a new bitmap node */ |
| node = PyObject_GC_NewVar( |
| PyHamtNode_Bitmap, &_PyHamt_BitmapNode_Type, size); |
| if (node == NULL) { |
| return NULL; |
| } |
| |
| Py_SIZE(node) = size; |
| |
| for (i = 0; i < size; i++) { |
| node->b_array[i] = NULL; |
| } |
| |
| node->b_bitmap = 0; |
| |
| _PyObject_GC_TRACK(node); |
| |
| if (size == 0 && _empty_bitmap_node == NULL) { |
| /* Since bitmap nodes are immutable, we can cache the instance |
| for size=0 and reuse it whenever we need an empty bitmap node. |
| */ |
| _empty_bitmap_node = node; |
| Py_INCREF(_empty_bitmap_node); |
| } |
| |
| return (PyHamtNode *)node; |
| } |
| |
| static inline Py_ssize_t |
| hamt_node_bitmap_count(PyHamtNode_Bitmap *node) |
| { |
| return Py_SIZE(node) / 2; |
| } |
| |
| static PyHamtNode_Bitmap * |
| hamt_node_bitmap_clone(PyHamtNode_Bitmap *node) |
| { |
| /* Clone a bitmap node; return a new one with the same child notes. */ |
| |
| PyHamtNode_Bitmap *clone; |
| Py_ssize_t i; |
| |
| clone = (PyHamtNode_Bitmap *)hamt_node_bitmap_new(Py_SIZE(node)); |
| if (clone == NULL) { |
| return NULL; |
| } |
| |
| for (i = 0; i < Py_SIZE(node); i++) { |
| Py_XINCREF(node->b_array[i]); |
| clone->b_array[i] = node->b_array[i]; |
| } |
| |
| clone->b_bitmap = node->b_bitmap; |
| return clone; |
| } |
| |
| static PyHamtNode_Bitmap * |
| hamt_node_bitmap_clone_without(PyHamtNode_Bitmap *o, uint32_t bit) |
| { |
| assert(bit & o->b_bitmap); |
| assert(hamt_node_bitmap_count(o) > 1); |
| |
| PyHamtNode_Bitmap *new = (PyHamtNode_Bitmap *)hamt_node_bitmap_new( |
| Py_SIZE(o) - 2); |
| if (new == NULL) { |
| return NULL; |
| } |
| |
| uint32_t idx = hamt_bitindex(o->b_bitmap, bit); |
| uint32_t key_idx = 2 * idx; |
| uint32_t val_idx = key_idx + 1; |
| uint32_t i; |
| |
| for (i = 0; i < key_idx; i++) { |
| Py_XINCREF(o->b_array[i]); |
| new->b_array[i] = o->b_array[i]; |
| } |
| |
| assert(Py_SIZE(o) >= 0 && Py_SIZE(o) <= 32); |
| for (i = val_idx + 1; i < (uint32_t)Py_SIZE(o); i++) { |
| Py_XINCREF(o->b_array[i]); |
| new->b_array[i - 2] = o->b_array[i]; |
| } |
| |
| new->b_bitmap = o->b_bitmap & ~bit; |
| return new; |
| } |
| |
| static PyHamtNode * |
| hamt_node_new_bitmap_or_collision(uint32_t shift, |
| PyObject *key1, PyObject *val1, |
| int32_t key2_hash, |
| PyObject *key2, PyObject *val2) |
| { |
| /* Helper method. Creates a new node for key1/val and key2/val2 |
| pairs. |
| |
| If key1 hash is equal to the hash of key2, a Collision node |
| will be created. If they are not equal, a Bitmap node is |
| created. |
| */ |
| |
| int32_t key1_hash = hamt_hash(key1); |
| if (key1_hash == -1) { |
| return NULL; |
| } |
| |
| if (key1_hash == key2_hash) { |
| PyHamtNode_Collision *n; |
| n = (PyHamtNode_Collision *)hamt_node_collision_new(key1_hash, 4); |
| if (n == NULL) { |
| return NULL; |
| } |
| |
| Py_INCREF(key1); |
| n->c_array[0] = key1; |
| Py_INCREF(val1); |
| n->c_array[1] = val1; |
| |
| Py_INCREF(key2); |
| n->c_array[2] = key2; |
| Py_INCREF(val2); |
| n->c_array[3] = val2; |
| |
| return (PyHamtNode *)n; |
| } |
| else { |
| int added_leaf = 0; |
| PyHamtNode *n = hamt_node_bitmap_new(0); |
| if (n == NULL) { |
| return NULL; |
| } |
| |
| PyHamtNode *n2 = hamt_node_assoc( |
| n, shift, key1_hash, key1, val1, &added_leaf); |
| Py_DECREF(n); |
| if (n2 == NULL) { |
| return NULL; |
| } |
| |
| n = hamt_node_assoc(n2, shift, key2_hash, key2, val2, &added_leaf); |
| Py_DECREF(n2); |
| if (n == NULL) { |
| return NULL; |
| } |
| |
| return n; |
| } |
| } |
| |
| static PyHamtNode * |
| hamt_node_bitmap_assoc(PyHamtNode_Bitmap *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject *val, int* added_leaf) |
| { |
| /* assoc operation for bitmap nodes. |
| |
| Return: a new node, or self if key/val already is in the |
| collection. |
| |
| 'added_leaf' is later used in '_PyHamt_Assoc' to determine if |
| `hamt.set(key, val)` increased the size of the collection. |
| */ |
| |
| uint32_t bit = hamt_bitpos(hash, shift); |
| uint32_t idx = hamt_bitindex(self->b_bitmap, bit); |
| |
| /* Bitmap node layout: |
| |
| +------+------+------+------+ --- +------+------+ |
| | key1 | val1 | key2 | val2 | ... | keyN | valN | |
| +------+------+------+------+ --- +------+------+ |
| where `N < Py_SIZE(node)`. |
| |
| The `node->b_bitmap` field is a bitmap. For a given |
| `(shift, hash)` pair we can determine: |
| |
| - If this node has the corresponding key/val slots. |
| - The index of key/val slots. |
| */ |
| |
| if (self->b_bitmap & bit) { |
| /* The key is set in this node */ |
| |
| uint32_t key_idx = 2 * idx; |
| uint32_t val_idx = key_idx + 1; |
| |
| assert(val_idx < (size_t)Py_SIZE(self)); |
| |
| PyObject *key_or_null = self->b_array[key_idx]; |
| PyObject *val_or_node = self->b_array[val_idx]; |
| |
| if (key_or_null == NULL) { |
| /* key is NULL. This means that we have a few keys |
| that have the same (hash, shift) pair. */ |
| |
| assert(val_or_node != NULL); |
| |
| PyHamtNode *sub_node = hamt_node_assoc( |
| (PyHamtNode *)val_or_node, |
| shift + 5, hash, key, val, added_leaf); |
| if (sub_node == NULL) { |
| return NULL; |
| } |
| |
| if (val_or_node == (PyObject *)sub_node) { |
| Py_DECREF(sub_node); |
| Py_INCREF(self); |
| return (PyHamtNode *)self; |
| } |
| |
| PyHamtNode_Bitmap *ret = hamt_node_bitmap_clone(self); |
| if (ret == NULL) { |
| return NULL; |
| } |
| Py_SETREF(ret->b_array[val_idx], (PyObject*)sub_node); |
| return (PyHamtNode *)ret; |
| } |
| |
| assert(key != NULL); |
| /* key is not NULL. This means that we have only one other |
| key in this collection that matches our hash for this shift. */ |
| |
| int comp_err = PyObject_RichCompareBool(key, key_or_null, Py_EQ); |
| if (comp_err < 0) { /* exception in __eq__ */ |
| return NULL; |
| } |
| if (comp_err == 1) { /* key == key_or_null */ |
| if (val == val_or_node) { |
| /* we already have the same key/val pair; return self. */ |
| Py_INCREF(self); |
| return (PyHamtNode *)self; |
| } |
| |
| /* We're setting a new value for the key we had before. |
| Make a new bitmap node with a replaced value, and return it. */ |
| PyHamtNode_Bitmap *ret = hamt_node_bitmap_clone(self); |
| if (ret == NULL) { |
| return NULL; |
| } |
| Py_INCREF(val); |
| Py_SETREF(ret->b_array[val_idx], val); |
| return (PyHamtNode *)ret; |
| } |
| |
| /* It's a new key, and it has the same index as *one* another key. |
| We have a collision. We need to create a new node which will |
| combine the existing key and the key we're adding. |
| |
| `hamt_node_new_bitmap_or_collision` will either create a new |
| Collision node if the keys have identical hashes, or |
| a new Bitmap node. |
| */ |
| PyHamtNode *sub_node = hamt_node_new_bitmap_or_collision( |
| shift + 5, |
| key_or_null, val_or_node, /* existing key/val */ |
| hash, |
| key, val /* new key/val */ |
| ); |
| if (sub_node == NULL) { |
| return NULL; |
| } |
| |
| PyHamtNode_Bitmap *ret = hamt_node_bitmap_clone(self); |
| if (ret == NULL) { |
| Py_DECREF(sub_node); |
| return NULL; |
| } |
| Py_SETREF(ret->b_array[key_idx], NULL); |
| Py_SETREF(ret->b_array[val_idx], (PyObject *)sub_node); |
| |
| *added_leaf = 1; |
| return (PyHamtNode *)ret; |
| } |
| else { |
| /* There was no key before with the same (shift,hash). */ |
| |
| uint32_t n = hamt_bitcount(self->b_bitmap); |
| |
| if (n >= 16) { |
| /* When we have a situation where we want to store more |
| than 16 nodes at one level of the tree, we no longer |
| want to use the Bitmap node with bitmap encoding. |
| |
| Instead we start using an Array node, which has |
| simpler (faster) implementation at the expense of |
| having preallocated 32 pointers for its keys/values |
| pairs. |
| |
| Small hamt objects (<30 keys) usually don't have any |
| Array nodes at all. Between ~30 and ~400 keys hamt |
| objects usually have one Array node, and usually it's |
| a root node. |
| */ |
| |
| uint32_t jdx = hamt_mask(hash, shift); |
| /* 'jdx' is the index of where the new key should be added |
| in the new Array node we're about to create. */ |
| |
| PyHamtNode *empty = NULL; |
| PyHamtNode_Array *new_node = NULL; |
| PyHamtNode *res = NULL; |
| |
| /* Create a new Array node. */ |
| new_node = (PyHamtNode_Array *)hamt_node_array_new(n + 1); |
| if (new_node == NULL) { |
| goto fin; |
| } |
| |
| /* Create an empty bitmap node for the next |
| hamt_node_assoc call. */ |
| empty = hamt_node_bitmap_new(0); |
| if (empty == NULL) { |
| goto fin; |
| } |
| |
| /* Make a new bitmap node for the key/val we're adding. |
| Set that bitmap node to new-array-node[jdx]. */ |
| new_node->a_array[jdx] = hamt_node_assoc( |
| empty, shift + 5, hash, key, val, added_leaf); |
| if (new_node->a_array[jdx] == NULL) { |
| goto fin; |
| } |
| |
| /* Copy existing key/value pairs from the current Bitmap |
| node to the new Array node we've just created. */ |
| Py_ssize_t i, j; |
| for (i = 0, j = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| if (((self->b_bitmap >> i) & 1) != 0) { |
| /* Ensure we don't accidentally override `jdx` element |
| we set few lines above. |
| */ |
| assert(new_node->a_array[i] == NULL); |
| |
| if (self->b_array[j] == NULL) { |
| new_node->a_array[i] = |
| (PyHamtNode *)self->b_array[j + 1]; |
| Py_INCREF(new_node->a_array[i]); |
| } |
| else { |
| int32_t rehash = hamt_hash(self->b_array[j]); |
| if (rehash == -1) { |
| goto fin; |
| } |
| |
| new_node->a_array[i] = hamt_node_assoc( |
| empty, shift + 5, |
| rehash, |
| self->b_array[j], |
| self->b_array[j + 1], |
| added_leaf); |
| |
| if (new_node->a_array[i] == NULL) { |
| goto fin; |
| } |
| } |
| j += 2; |
| } |
| } |
| |
| VALIDATE_ARRAY_NODE(new_node) |
| |
| /* That's it! */ |
| res = (PyHamtNode *)new_node; |
| |
| fin: |
| Py_XDECREF(empty); |
| if (res == NULL) { |
| Py_XDECREF(new_node); |
| } |
| return res; |
| } |
| else { |
| /* We have less than 16 keys at this level; let's just |
| create a new bitmap node out of this node with the |
| new key/val pair added. */ |
| |
| uint32_t key_idx = 2 * idx; |
| uint32_t val_idx = key_idx + 1; |
| uint32_t i; |
| |
| *added_leaf = 1; |
| |
| /* Allocate new Bitmap node which can have one more key/val |
| pair in addition to what we have already. */ |
| PyHamtNode_Bitmap *new_node = |
| (PyHamtNode_Bitmap *)hamt_node_bitmap_new(2 * (n + 1)); |
| if (new_node == NULL) { |
| return NULL; |
| } |
| |
| /* Copy all keys/values that will be before the new key/value |
| we are adding. */ |
| for (i = 0; i < key_idx; i++) { |
| Py_XINCREF(self->b_array[i]); |
| new_node->b_array[i] = self->b_array[i]; |
| } |
| |
| /* Set the new key/value to the new Bitmap node. */ |
| Py_INCREF(key); |
| new_node->b_array[key_idx] = key; |
| Py_INCREF(val); |
| new_node->b_array[val_idx] = val; |
| |
| /* Copy all keys/values that will be after the new key/value |
| we are adding. */ |
| assert(Py_SIZE(self) >= 0 && Py_SIZE(self) <= 32); |
| for (i = key_idx; i < (uint32_t)Py_SIZE(self); i++) { |
| Py_XINCREF(self->b_array[i]); |
| new_node->b_array[i + 2] = self->b_array[i]; |
| } |
| |
| new_node->b_bitmap = self->b_bitmap | bit; |
| return (PyHamtNode *)new_node; |
| } |
| } |
| } |
| |
| static hamt_without_t |
| hamt_node_bitmap_without(PyHamtNode_Bitmap *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, |
| PyHamtNode **new_node) |
| { |
| uint32_t bit = hamt_bitpos(hash, shift); |
| if ((self->b_bitmap & bit) == 0) { |
| return W_NOT_FOUND; |
| } |
| |
| uint32_t idx = hamt_bitindex(self->b_bitmap, bit); |
| |
| uint32_t key_idx = 2 * idx; |
| uint32_t val_idx = key_idx + 1; |
| |
| PyObject *key_or_null = self->b_array[key_idx]; |
| PyObject *val_or_node = self->b_array[val_idx]; |
| |
| if (key_or_null == NULL) { |
| /* key == NULL means that 'value' is another tree node. */ |
| |
| PyHamtNode *sub_node = NULL; |
| |
| hamt_without_t res = hamt_node_without( |
| (PyHamtNode *)val_or_node, |
| shift + 5, hash, key, &sub_node); |
| |
| switch (res) { |
| case W_EMPTY: |
| /* It's impossible for us to receive a W_EMPTY here: |
| |
| - Array nodes are converted to Bitmap nodes when |
| we delete 16th item from them; |
| |
| - Collision nodes are converted to Bitmap when |
| there is one item in them; |
| |
| - Bitmap node's without() inlines single-item |
| sub-nodes. |
| |
| So in no situation we can have a single-item |
| Bitmap child of another Bitmap node. |
| */ |
| Py_UNREACHABLE(); |
| |
| case W_NEWNODE: { |
| assert(sub_node != NULL); |
| |
| if (IS_BITMAP_NODE(sub_node)) { |
| PyHamtNode_Bitmap *sub_tree = (PyHamtNode_Bitmap *)sub_node; |
| if (hamt_node_bitmap_count(sub_tree) == 1 && |
| sub_tree->b_array[0] != NULL) |
| { |
| /* A bitmap node with one key/value pair. Just |
| merge it into this node. |
| |
| Note that we don't inline Bitmap nodes that |
| have a NULL key -- those nodes point to another |
| tree level, and we cannot simply move tree levels |
| up or down. |
| */ |
| |
| PyHamtNode_Bitmap *clone = hamt_node_bitmap_clone(self); |
| if (clone == NULL) { |
| Py_DECREF(sub_node); |
| return W_ERROR; |
| } |
| |
| PyObject *key = sub_tree->b_array[0]; |
| PyObject *val = sub_tree->b_array[1]; |
| |
| Py_INCREF(key); |
| Py_XSETREF(clone->b_array[key_idx], key); |
| Py_INCREF(val); |
| Py_SETREF(clone->b_array[val_idx], val); |
| |
| Py_DECREF(sub_tree); |
| |
| *new_node = (PyHamtNode *)clone; |
| return W_NEWNODE; |
| } |
| } |
| |
| #ifdef Py_DEBUG |
| /* Ensure that Collision.without implementation |
| converts to Bitmap nodes itself. |
| */ |
| if (IS_COLLISION_NODE(sub_node)) { |
| assert(hamt_node_collision_count( |
| (PyHamtNode_Collision*)sub_node) > 1); |
| } |
| #endif |
| |
| PyHamtNode_Bitmap *clone = hamt_node_bitmap_clone(self); |
| if (clone == NULL) { |
| return W_ERROR; |
| } |
| |
| Py_SETREF(clone->b_array[val_idx], |
| (PyObject *)sub_node); /* borrow */ |
| |
| *new_node = (PyHamtNode *)clone; |
| return W_NEWNODE; |
| } |
| |
| case W_ERROR: |
| case W_NOT_FOUND: |
| assert(sub_node == NULL); |
| return res; |
| |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| else { |
| /* We have a regular key/value pair */ |
| |
| int cmp = PyObject_RichCompareBool(key_or_null, key, Py_EQ); |
| if (cmp < 0) { |
| return W_ERROR; |
| } |
| if (cmp == 0) { |
| return W_NOT_FOUND; |
| } |
| |
| if (hamt_node_bitmap_count(self) == 1) { |
| return W_EMPTY; |
| } |
| |
| *new_node = (PyHamtNode *) |
| hamt_node_bitmap_clone_without(self, bit); |
| if (*new_node == NULL) { |
| return W_ERROR; |
| } |
| |
| return W_NEWNODE; |
| } |
| } |
| |
| static hamt_find_t |
| hamt_node_bitmap_find(PyHamtNode_Bitmap *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject **val) |
| { |
| /* Lookup a key in a Bitmap node. */ |
| |
| uint32_t bit = hamt_bitpos(hash, shift); |
| uint32_t idx; |
| uint32_t key_idx; |
| uint32_t val_idx; |
| PyObject *key_or_null; |
| PyObject *val_or_node; |
| int comp_err; |
| |
| if ((self->b_bitmap & bit) == 0) { |
| return F_NOT_FOUND; |
| } |
| |
| idx = hamt_bitindex(self->b_bitmap, bit); |
| key_idx = idx * 2; |
| val_idx = key_idx + 1; |
| |
| assert(val_idx < (size_t)Py_SIZE(self)); |
| |
| key_or_null = self->b_array[key_idx]; |
| val_or_node = self->b_array[val_idx]; |
| |
| if (key_or_null == NULL) { |
| /* There are a few keys that have the same hash at the current shift |
| that match our key. Dispatch the lookup further down the tree. */ |
| assert(val_or_node != NULL); |
| return hamt_node_find((PyHamtNode *)val_or_node, |
| shift + 5, hash, key, val); |
| } |
| |
| /* We have only one key -- a potential match. Let's compare if the |
| key we are looking at is equal to the key we are looking for. */ |
| assert(key != NULL); |
| comp_err = PyObject_RichCompareBool(key, key_or_null, Py_EQ); |
| if (comp_err < 0) { /* exception in __eq__ */ |
| return F_ERROR; |
| } |
| if (comp_err == 1) { /* key == key_or_null */ |
| *val = val_or_node; |
| return F_FOUND; |
| } |
| |
| return F_NOT_FOUND; |
| } |
| |
| static int |
| hamt_node_bitmap_traverse(PyHamtNode_Bitmap *self, visitproc visit, void *arg) |
| { |
| /* Bitmap's tp_traverse */ |
| |
| Py_ssize_t i; |
| |
| for (i = Py_SIZE(self); --i >= 0; ) { |
| Py_VISIT(self->b_array[i]); |
| } |
| |
| return 0; |
| } |
| |
| static void |
| hamt_node_bitmap_dealloc(PyHamtNode_Bitmap *self) |
| { |
| /* Bitmap's tp_dealloc */ |
| |
| Py_ssize_t len = Py_SIZE(self); |
| Py_ssize_t i; |
| |
| PyObject_GC_UnTrack(self); |
| Py_TRASHCAN_BEGIN(self, hamt_node_bitmap_dealloc) |
| |
| if (len > 0) { |
| i = len; |
| while (--i >= 0) { |
| Py_XDECREF(self->b_array[i]); |
| } |
| } |
| |
| Py_TYPE(self)->tp_free((PyObject *)self); |
| Py_TRASHCAN_END |
| } |
| |
| #ifdef Py_DEBUG |
| static int |
| hamt_node_bitmap_dump(PyHamtNode_Bitmap *node, |
| _PyUnicodeWriter *writer, int level) |
| { |
| /* Debug build: __dump__() method implementation for Bitmap nodes. */ |
| |
| Py_ssize_t i; |
| PyObject *tmp1; |
| PyObject *tmp2; |
| |
| if (_hamt_dump_ident(writer, level + 1)) { |
| goto error; |
| } |
| |
| if (_hamt_dump_format(writer, "BitmapNode(size=%zd count=%zd ", |
| Py_SIZE(node), Py_SIZE(node) / 2)) |
| { |
| goto error; |
| } |
| |
| tmp1 = PyLong_FromUnsignedLong(node->b_bitmap); |
| if (tmp1 == NULL) { |
| goto error; |
| } |
| tmp2 = _PyLong_Format(tmp1, 2); |
| Py_DECREF(tmp1); |
| if (tmp2 == NULL) { |
| goto error; |
| } |
| if (_hamt_dump_format(writer, "bitmap=%S id=%p):\n", tmp2, node)) { |
| Py_DECREF(tmp2); |
| goto error; |
| } |
| Py_DECREF(tmp2); |
| |
| for (i = 0; i < Py_SIZE(node); i += 2) { |
| PyObject *key_or_null = node->b_array[i]; |
| PyObject *val_or_node = node->b_array[i + 1]; |
| |
| if (_hamt_dump_ident(writer, level + 2)) { |
| goto error; |
| } |
| |
| if (key_or_null == NULL) { |
| if (_hamt_dump_format(writer, "NULL:\n")) { |
| goto error; |
| } |
| |
| if (hamt_node_dump((PyHamtNode *)val_or_node, |
| writer, level + 2)) |
| { |
| goto error; |
| } |
| } |
| else { |
| if (_hamt_dump_format(writer, "%R: %R", key_or_null, |
| val_or_node)) |
| { |
| goto error; |
| } |
| } |
| |
| if (_hamt_dump_format(writer, "\n")) { |
| goto error; |
| } |
| } |
| |
| return 0; |
| error: |
| return -1; |
| } |
| #endif /* Py_DEBUG */ |
| |
| |
| /////////////////////////////////// Collision Node |
| |
| |
| static PyHamtNode * |
| hamt_node_collision_new(int32_t hash, Py_ssize_t size) |
| { |
| /* Create a new Collision node. */ |
| |
| PyHamtNode_Collision *node; |
| Py_ssize_t i; |
| |
| assert(size >= 4); |
| assert(size % 2 == 0); |
| |
| node = PyObject_GC_NewVar( |
| PyHamtNode_Collision, &_PyHamt_CollisionNode_Type, size); |
| if (node == NULL) { |
| return NULL; |
| } |
| |
| for (i = 0; i < size; i++) { |
| node->c_array[i] = NULL; |
| } |
| |
| Py_SIZE(node) = size; |
| node->c_hash = hash; |
| |
| _PyObject_GC_TRACK(node); |
| |
| return (PyHamtNode *)node; |
| } |
| |
| static hamt_find_t |
| hamt_node_collision_find_index(PyHamtNode_Collision *self, PyObject *key, |
| Py_ssize_t *idx) |
| { |
| /* Lookup `key` in the Collision node `self`. Set the index of the |
| found key to 'idx'. */ |
| |
| Py_ssize_t i; |
| PyObject *el; |
| |
| for (i = 0; i < Py_SIZE(self); i += 2) { |
| el = self->c_array[i]; |
| |
| assert(el != NULL); |
| int cmp = PyObject_RichCompareBool(key, el, Py_EQ); |
| if (cmp < 0) { |
| return F_ERROR; |
| } |
| if (cmp == 1) { |
| *idx = i; |
| return F_FOUND; |
| } |
| } |
| |
| return F_NOT_FOUND; |
| } |
| |
| static PyHamtNode * |
| hamt_node_collision_assoc(PyHamtNode_Collision *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject *val, int* added_leaf) |
| { |
| /* Set a new key to this level (currently a Collision node) |
| of the tree. */ |
| |
| if (hash == self->c_hash) { |
| /* The hash of the 'key' we are adding matches the hash of |
| other keys in this Collision node. */ |
| |
| Py_ssize_t key_idx = -1; |
| hamt_find_t found; |
| PyHamtNode_Collision *new_node; |
| Py_ssize_t i; |
| |
| /* Let's try to lookup the new 'key', maybe we already have it. */ |
| found = hamt_node_collision_find_index(self, key, &key_idx); |
| switch (found) { |
| case F_ERROR: |
| /* Exception. */ |
| return NULL; |
| |
| case F_NOT_FOUND: |
| /* This is a totally new key. Clone the current node, |
| add a new key/value to the cloned node. */ |
| |
| new_node = (PyHamtNode_Collision *)hamt_node_collision_new( |
| self->c_hash, Py_SIZE(self) + 2); |
| if (new_node == NULL) { |
| return NULL; |
| } |
| |
| for (i = 0; i < Py_SIZE(self); i++) { |
| Py_INCREF(self->c_array[i]); |
| new_node->c_array[i] = self->c_array[i]; |
| } |
| |
| Py_INCREF(key); |
| new_node->c_array[i] = key; |
| Py_INCREF(val); |
| new_node->c_array[i + 1] = val; |
| |
| *added_leaf = 1; |
| return (PyHamtNode *)new_node; |
| |
| case F_FOUND: |
| /* There's a key which is equal to the key we are adding. */ |
| |
| assert(key_idx >= 0); |
| assert(key_idx < Py_SIZE(self)); |
| Py_ssize_t val_idx = key_idx + 1; |
| |
| if (self->c_array[val_idx] == val) { |
| /* We're setting a key/value pair that's already set. */ |
| Py_INCREF(self); |
| return (PyHamtNode *)self; |
| } |
| |
| /* We need to replace old value for the key |
| with a new value. Create a new Collision node.*/ |
| new_node = (PyHamtNode_Collision *)hamt_node_collision_new( |
| self->c_hash, Py_SIZE(self)); |
| if (new_node == NULL) { |
| return NULL; |
| } |
| |
| /* Copy all elements of the old node to the new one. */ |
| for (i = 0; i < Py_SIZE(self); i++) { |
| Py_INCREF(self->c_array[i]); |
| new_node->c_array[i] = self->c_array[i]; |
| } |
| |
| /* Replace the old value with the new value for the our key. */ |
| Py_DECREF(new_node->c_array[val_idx]); |
| Py_INCREF(val); |
| new_node->c_array[val_idx] = val; |
| |
| return (PyHamtNode *)new_node; |
| |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| else { |
| /* The hash of the new key is different from the hash that |
| all keys of this Collision node have. |
| |
| Create a Bitmap node inplace with two children: |
| key/value pair that we're adding, and the Collision node |
| we're replacing on this tree level. |
| */ |
| |
| PyHamtNode_Bitmap *new_node; |
| PyHamtNode *assoc_res; |
| |
| new_node = (PyHamtNode_Bitmap *)hamt_node_bitmap_new(2); |
| if (new_node == NULL) { |
| return NULL; |
| } |
| new_node->b_bitmap = hamt_bitpos(self->c_hash, shift); |
| Py_INCREF(self); |
| new_node->b_array[1] = (PyObject*) self; |
| |
| assoc_res = hamt_node_bitmap_assoc( |
| new_node, shift, hash, key, val, added_leaf); |
| Py_DECREF(new_node); |
| return assoc_res; |
| } |
| } |
| |
| static inline Py_ssize_t |
| hamt_node_collision_count(PyHamtNode_Collision *node) |
| { |
| return Py_SIZE(node) / 2; |
| } |
| |
| static hamt_without_t |
| hamt_node_collision_without(PyHamtNode_Collision *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, |
| PyHamtNode **new_node) |
| { |
| if (hash != self->c_hash) { |
| return W_NOT_FOUND; |
| } |
| |
| Py_ssize_t key_idx = -1; |
| hamt_find_t found = hamt_node_collision_find_index(self, key, &key_idx); |
| |
| switch (found) { |
| case F_ERROR: |
| return W_ERROR; |
| |
| case F_NOT_FOUND: |
| return W_NOT_FOUND; |
| |
| case F_FOUND: |
| assert(key_idx >= 0); |
| assert(key_idx < Py_SIZE(self)); |
| |
| Py_ssize_t new_count = hamt_node_collision_count(self) - 1; |
| |
| if (new_count == 0) { |
| /* The node has only one key/value pair and it's for the |
| key we're trying to delete. So a new node will be empty |
| after the removal. |
| */ |
| return W_EMPTY; |
| } |
| |
| if (new_count == 1) { |
| /* The node has two keys, and after deletion the |
| new Collision node would have one. Collision nodes |
| with one key shouldn't exist, so convert it to a |
| Bitmap node. |
| */ |
| PyHamtNode_Bitmap *node = (PyHamtNode_Bitmap *) |
| hamt_node_bitmap_new(2); |
| if (node == NULL) { |
| return W_ERROR; |
| } |
| |
| if (key_idx == 0) { |
| Py_INCREF(self->c_array[2]); |
| node->b_array[0] = self->c_array[2]; |
| Py_INCREF(self->c_array[3]); |
| node->b_array[1] = self->c_array[3]; |
| } |
| else { |
| assert(key_idx == 2); |
| Py_INCREF(self->c_array[0]); |
| node->b_array[0] = self->c_array[0]; |
| Py_INCREF(self->c_array[1]); |
| node->b_array[1] = self->c_array[1]; |
| } |
| |
| node->b_bitmap = hamt_bitpos(hash, shift); |
| |
| *new_node = (PyHamtNode *)node; |
| return W_NEWNODE; |
| } |
| |
| /* Allocate a new Collision node with capacity for one |
| less key/value pair */ |
| PyHamtNode_Collision *new = (PyHamtNode_Collision *) |
| hamt_node_collision_new( |
| self->c_hash, Py_SIZE(self) - 2); |
| if (new == NULL) { |
| return W_ERROR; |
| } |
| |
| /* Copy all other keys from `self` to `new` */ |
| Py_ssize_t i; |
| for (i = 0; i < key_idx; i++) { |
| Py_INCREF(self->c_array[i]); |
| new->c_array[i] = self->c_array[i]; |
| } |
| for (i = key_idx + 2; i < Py_SIZE(self); i++) { |
| Py_INCREF(self->c_array[i]); |
| new->c_array[i - 2] = self->c_array[i]; |
| } |
| |
| *new_node = (PyHamtNode*)new; |
| return W_NEWNODE; |
| |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| |
| static hamt_find_t |
| hamt_node_collision_find(PyHamtNode_Collision *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject **val) |
| { |
| /* Lookup `key` in the Collision node `self`. Set the value |
| for the found key to 'val'. */ |
| |
| Py_ssize_t idx = -1; |
| hamt_find_t res; |
| |
| res = hamt_node_collision_find_index(self, key, &idx); |
| if (res == F_ERROR || res == F_NOT_FOUND) { |
| return res; |
| } |
| |
| assert(idx >= 0); |
| assert(idx + 1 < Py_SIZE(self)); |
| |
| *val = self->c_array[idx + 1]; |
| assert(*val != NULL); |
| |
| return F_FOUND; |
| } |
| |
| |
| static int |
| hamt_node_collision_traverse(PyHamtNode_Collision *self, |
| visitproc visit, void *arg) |
| { |
| /* Collision's tp_traverse */ |
| |
| Py_ssize_t i; |
| |
| for (i = Py_SIZE(self); --i >= 0; ) { |
| Py_VISIT(self->c_array[i]); |
| } |
| |
| return 0; |
| } |
| |
| static void |
| hamt_node_collision_dealloc(PyHamtNode_Collision *self) |
| { |
| /* Collision's tp_dealloc */ |
| |
| Py_ssize_t len = Py_SIZE(self); |
| |
| PyObject_GC_UnTrack(self); |
| Py_TRASHCAN_BEGIN(self, hamt_node_collision_dealloc) |
| |
| if (len > 0) { |
| |
| while (--len >= 0) { |
| Py_XDECREF(self->c_array[len]); |
| } |
| } |
| |
| Py_TYPE(self)->tp_free((PyObject *)self); |
| Py_TRASHCAN_END |
| } |
| |
| #ifdef Py_DEBUG |
| static int |
| hamt_node_collision_dump(PyHamtNode_Collision *node, |
| _PyUnicodeWriter *writer, int level) |
| { |
| /* Debug build: __dump__() method implementation for Collision nodes. */ |
| |
| Py_ssize_t i; |
| |
| if (_hamt_dump_ident(writer, level + 1)) { |
| goto error; |
| } |
| |
| if (_hamt_dump_format(writer, "CollisionNode(size=%zd id=%p):\n", |
| Py_SIZE(node), node)) |
| { |
| goto error; |
| } |
| |
| for (i = 0; i < Py_SIZE(node); i += 2) { |
| PyObject *key = node->c_array[i]; |
| PyObject *val = node->c_array[i + 1]; |
| |
| if (_hamt_dump_ident(writer, level + 2)) { |
| goto error; |
| } |
| |
| if (_hamt_dump_format(writer, "%R: %R\n", key, val)) { |
| goto error; |
| } |
| } |
| |
| return 0; |
| error: |
| return -1; |
| } |
| #endif /* Py_DEBUG */ |
| |
| |
| /////////////////////////////////// Array Node |
| |
| |
| static PyHamtNode * |
| hamt_node_array_new(Py_ssize_t count) |
| { |
| Py_ssize_t i; |
| |
| PyHamtNode_Array *node = PyObject_GC_New( |
| PyHamtNode_Array, &_PyHamt_ArrayNode_Type); |
| if (node == NULL) { |
| return NULL; |
| } |
| |
| for (i = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| node->a_array[i] = NULL; |
| } |
| |
| node->a_count = count; |
| |
| _PyObject_GC_TRACK(node); |
| return (PyHamtNode *)node; |
| } |
| |
| static PyHamtNode_Array * |
| hamt_node_array_clone(PyHamtNode_Array *node) |
| { |
| PyHamtNode_Array *clone; |
| Py_ssize_t i; |
| |
| VALIDATE_ARRAY_NODE(node) |
| |
| /* Create a new Array node. */ |
| clone = (PyHamtNode_Array *)hamt_node_array_new(node->a_count); |
| if (clone == NULL) { |
| return NULL; |
| } |
| |
| /* Copy all elements from the current Array node to the new one. */ |
| for (i = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| Py_XINCREF(node->a_array[i]); |
| clone->a_array[i] = node->a_array[i]; |
| } |
| |
| VALIDATE_ARRAY_NODE(clone) |
| return clone; |
| } |
| |
| static PyHamtNode * |
| hamt_node_array_assoc(PyHamtNode_Array *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject *val, int* added_leaf) |
| { |
| /* Set a new key to this level (currently a Collision node) |
| of the tree. |
| |
| Array nodes don't store values, they can only point to |
| other nodes. They are simple arrays of 32 BaseNode pointers/ |
| */ |
| |
| uint32_t idx = hamt_mask(hash, shift); |
| PyHamtNode *node = self->a_array[idx]; |
| PyHamtNode *child_node; |
| PyHamtNode_Array *new_node; |
| Py_ssize_t i; |
| |
| if (node == NULL) { |
| /* There's no child node for the given hash. Create a new |
| Bitmap node for this key. */ |
| |
| PyHamtNode_Bitmap *empty = NULL; |
| |
| /* Get an empty Bitmap node to work with. */ |
| empty = (PyHamtNode_Bitmap *)hamt_node_bitmap_new(0); |
| if (empty == NULL) { |
| return NULL; |
| } |
| |
| /* Set key/val to the newly created empty Bitmap, thus |
| creating a new Bitmap node with our key/value pair. */ |
| child_node = hamt_node_bitmap_assoc( |
| empty, |
| shift + 5, hash, key, val, added_leaf); |
| Py_DECREF(empty); |
| if (child_node == NULL) { |
| return NULL; |
| } |
| |
| /* Create a new Array node. */ |
| new_node = (PyHamtNode_Array *)hamt_node_array_new(self->a_count + 1); |
| if (new_node == NULL) { |
| Py_DECREF(child_node); |
| return NULL; |
| } |
| |
| /* Copy all elements from the current Array node to the |
| new one. */ |
| for (i = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| Py_XINCREF(self->a_array[i]); |
| new_node->a_array[i] = self->a_array[i]; |
| } |
| |
| assert(new_node->a_array[idx] == NULL); |
| new_node->a_array[idx] = child_node; /* borrow */ |
| VALIDATE_ARRAY_NODE(new_node) |
| } |
| else { |
| /* There's a child node for the given hash. |
| Set the key to it./ */ |
| child_node = hamt_node_assoc( |
| node, shift + 5, hash, key, val, added_leaf); |
| if (child_node == NULL) { |
| return NULL; |
| } |
| else if (child_node == (PyHamtNode *)self) { |
| Py_DECREF(child_node); |
| return (PyHamtNode *)self; |
| } |
| |
| new_node = hamt_node_array_clone(self); |
| if (new_node == NULL) { |
| Py_DECREF(child_node); |
| return NULL; |
| } |
| |
| Py_SETREF(new_node->a_array[idx], child_node); /* borrow */ |
| VALIDATE_ARRAY_NODE(new_node) |
| } |
| |
| return (PyHamtNode *)new_node; |
| } |
| |
| static hamt_without_t |
| hamt_node_array_without(PyHamtNode_Array *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, |
| PyHamtNode **new_node) |
| { |
| uint32_t idx = hamt_mask(hash, shift); |
| PyHamtNode *node = self->a_array[idx]; |
| |
| if (node == NULL) { |
| return W_NOT_FOUND; |
| } |
| |
| PyHamtNode *sub_node = NULL; |
| hamt_without_t res = hamt_node_without( |
| (PyHamtNode *)node, |
| shift + 5, hash, key, &sub_node); |
| |
| switch (res) { |
| case W_NOT_FOUND: |
| case W_ERROR: |
| assert(sub_node == NULL); |
| return res; |
| |
| case W_NEWNODE: { |
| /* We need to replace a node at the `idx` index. |
| Clone this node and replace. |
| */ |
| assert(sub_node != NULL); |
| |
| PyHamtNode_Array *clone = hamt_node_array_clone(self); |
| if (clone == NULL) { |
| Py_DECREF(sub_node); |
| return W_ERROR; |
| } |
| |
| Py_SETREF(clone->a_array[idx], sub_node); /* borrow */ |
| *new_node = (PyHamtNode*)clone; /* borrow */ |
| return W_NEWNODE; |
| } |
| |
| case W_EMPTY: { |
| assert(sub_node == NULL); |
| /* We need to remove a node at the `idx` index. |
| Calculate the size of the replacement Array node. |
| */ |
| Py_ssize_t new_count = self->a_count - 1; |
| |
| if (new_count == 0) { |
| return W_EMPTY; |
| } |
| |
| if (new_count >= 16) { |
| /* We convert Bitmap nodes to Array nodes, when a |
| Bitmap node needs to store more than 15 key/value |
| pairs. So we will create a new Array node if we |
| the number of key/values after deletion is still |
| greater than 15. |
| */ |
| |
| PyHamtNode_Array *new = hamt_node_array_clone(self); |
| if (new == NULL) { |
| return W_ERROR; |
| } |
| new->a_count = new_count; |
| Py_CLEAR(new->a_array[idx]); |
| |
| *new_node = (PyHamtNode*)new; /* borrow */ |
| return W_NEWNODE; |
| } |
| |
| /* New Array node would have less than 16 key/value |
| pairs. We need to create a replacement Bitmap node. */ |
| |
| Py_ssize_t bitmap_size = new_count * 2; |
| uint32_t bitmap = 0; |
| |
| PyHamtNode_Bitmap *new = (PyHamtNode_Bitmap *) |
| hamt_node_bitmap_new(bitmap_size); |
| if (new == NULL) { |
| return W_ERROR; |
| } |
| |
| Py_ssize_t new_i = 0; |
| for (uint32_t i = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| if (i == idx) { |
| /* Skip the node we are deleting. */ |
| continue; |
| } |
| |
| PyHamtNode *node = self->a_array[i]; |
| if (node == NULL) { |
| /* Skip any missing nodes. */ |
| continue; |
| } |
| |
| bitmap |= 1 << i; |
| |
| if (IS_BITMAP_NODE(node)) { |
| PyHamtNode_Bitmap *child = (PyHamtNode_Bitmap *)node; |
| |
| if (hamt_node_bitmap_count(child) == 1 && |
| child->b_array[0] != NULL) |
| { |
| /* node is a Bitmap with one key/value pair, just |
| merge it into the new Bitmap node we're building. |
| |
| Note that we don't inline Bitmap nodes that |
| have a NULL key -- those nodes point to another |
| tree level, and we cannot simply move tree levels |
| up or down. |
| */ |
| PyObject *key = child->b_array[0]; |
| PyObject *val = child->b_array[1]; |
| |
| Py_INCREF(key); |
| new->b_array[new_i] = key; |
| Py_INCREF(val); |
| new->b_array[new_i + 1] = val; |
| } |
| else { |
| new->b_array[new_i] = NULL; |
| Py_INCREF(node); |
| new->b_array[new_i + 1] = (PyObject*)node; |
| } |
| } |
| else { |
| |
| #ifdef Py_DEBUG |
| if (IS_COLLISION_NODE(node)) { |
| Py_ssize_t child_count = hamt_node_collision_count( |
| (PyHamtNode_Collision*)node); |
| assert(child_count > 1); |
| } |
| else if (IS_ARRAY_NODE(node)) { |
| assert(((PyHamtNode_Array*)node)->a_count >= 16); |
| } |
| #endif |
| |
| /* Just copy the node into our new Bitmap */ |
| new->b_array[new_i] = NULL; |
| Py_INCREF(node); |
| new->b_array[new_i + 1] = (PyObject*)node; |
| } |
| |
| new_i += 2; |
| } |
| |
| new->b_bitmap = bitmap; |
| *new_node = (PyHamtNode*)new; /* borrow */ |
| return W_NEWNODE; |
| } |
| |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| |
| static hamt_find_t |
| hamt_node_array_find(PyHamtNode_Array *self, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject **val) |
| { |
| /* Lookup `key` in the Array node `self`. Set the value |
| for the found key to 'val'. */ |
| |
| uint32_t idx = hamt_mask(hash, shift); |
| PyHamtNode *node; |
| |
| node = self->a_array[idx]; |
| if (node == NULL) { |
| return F_NOT_FOUND; |
| } |
| |
| /* Dispatch to the generic hamt_node_find */ |
| return hamt_node_find(node, shift + 5, hash, key, val); |
| } |
| |
| static int |
| hamt_node_array_traverse(PyHamtNode_Array *self, |
| visitproc visit, void *arg) |
| { |
| /* Array's tp_traverse */ |
| |
| Py_ssize_t i; |
| |
| for (i = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| Py_VISIT(self->a_array[i]); |
| } |
| |
| return 0; |
| } |
| |
| static void |
| hamt_node_array_dealloc(PyHamtNode_Array *self) |
| { |
| /* Array's tp_dealloc */ |
| |
| Py_ssize_t i; |
| |
| PyObject_GC_UnTrack(self); |
| Py_TRASHCAN_BEGIN(self, hamt_node_array_dealloc) |
| |
| for (i = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| Py_XDECREF(self->a_array[i]); |
| } |
| |
| Py_TYPE(self)->tp_free((PyObject *)self); |
| Py_TRASHCAN_END |
| } |
| |
| #ifdef Py_DEBUG |
| static int |
| hamt_node_array_dump(PyHamtNode_Array *node, |
| _PyUnicodeWriter *writer, int level) |
| { |
| /* Debug build: __dump__() method implementation for Array nodes. */ |
| |
| Py_ssize_t i; |
| |
| if (_hamt_dump_ident(writer, level + 1)) { |
| goto error; |
| } |
| |
| if (_hamt_dump_format(writer, "ArrayNode(id=%p):\n", node)) { |
| goto error; |
| } |
| |
| for (i = 0; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| if (node->a_array[i] == NULL) { |
| continue; |
| } |
| |
| if (_hamt_dump_ident(writer, level + 2)) { |
| goto error; |
| } |
| |
| if (_hamt_dump_format(writer, "%zd::\n", i)) { |
| goto error; |
| } |
| |
| if (hamt_node_dump(node->a_array[i], writer, level + 1)) { |
| goto error; |
| } |
| |
| if (_hamt_dump_format(writer, "\n")) { |
| goto error; |
| } |
| } |
| |
| return 0; |
| error: |
| return -1; |
| } |
| #endif /* Py_DEBUG */ |
| |
| |
| /////////////////////////////////// Node Dispatch |
| |
| |
| static PyHamtNode * |
| hamt_node_assoc(PyHamtNode *node, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject *val, int* added_leaf) |
| { |
| /* Set key/value to the 'node' starting with the given shift/hash. |
| Return a new node, or the same node if key/value already |
| set. |
| |
| added_leaf will be set to 1 if key/value wasn't in the |
| tree before. |
| |
| This method automatically dispatches to the suitable |
| hamt_node_{nodetype}_assoc method. |
| */ |
| |
| if (IS_BITMAP_NODE(node)) { |
| return hamt_node_bitmap_assoc( |
| (PyHamtNode_Bitmap *)node, |
| shift, hash, key, val, added_leaf); |
| } |
| else if (IS_ARRAY_NODE(node)) { |
| return hamt_node_array_assoc( |
| (PyHamtNode_Array *)node, |
| shift, hash, key, val, added_leaf); |
| } |
| else { |
| assert(IS_COLLISION_NODE(node)); |
| return hamt_node_collision_assoc( |
| (PyHamtNode_Collision *)node, |
| shift, hash, key, val, added_leaf); |
| } |
| } |
| |
| static hamt_without_t |
| hamt_node_without(PyHamtNode *node, |
| uint32_t shift, int32_t hash, |
| PyObject *key, |
| PyHamtNode **new_node) |
| { |
| if (IS_BITMAP_NODE(node)) { |
| return hamt_node_bitmap_without( |
| (PyHamtNode_Bitmap *)node, |
| shift, hash, key, |
| new_node); |
| } |
| else if (IS_ARRAY_NODE(node)) { |
| return hamt_node_array_without( |
| (PyHamtNode_Array *)node, |
| shift, hash, key, |
| new_node); |
| } |
| else { |
| assert(IS_COLLISION_NODE(node)); |
| return hamt_node_collision_without( |
| (PyHamtNode_Collision *)node, |
| shift, hash, key, |
| new_node); |
| } |
| } |
| |
| static hamt_find_t |
| hamt_node_find(PyHamtNode *node, |
| uint32_t shift, int32_t hash, |
| PyObject *key, PyObject **val) |
| { |
| /* Find the key in the node starting with the given shift/hash. |
| |
| If a value is found, the result will be set to F_FOUND, and |
| *val will point to the found value object. |
| |
| If a value wasn't found, the result will be set to F_NOT_FOUND. |
| |
| If an exception occurs during the call, the result will be F_ERROR. |
| |
| This method automatically dispatches to the suitable |
| hamt_node_{nodetype}_find method. |
| */ |
| |
| if (IS_BITMAP_NODE(node)) { |
| return hamt_node_bitmap_find( |
| (PyHamtNode_Bitmap *)node, |
| shift, hash, key, val); |
| |
| } |
| else if (IS_ARRAY_NODE(node)) { |
| return hamt_node_array_find( |
| (PyHamtNode_Array *)node, |
| shift, hash, key, val); |
| } |
| else { |
| assert(IS_COLLISION_NODE(node)); |
| return hamt_node_collision_find( |
| (PyHamtNode_Collision *)node, |
| shift, hash, key, val); |
| } |
| } |
| |
| #ifdef Py_DEBUG |
| static int |
| hamt_node_dump(PyHamtNode *node, |
| _PyUnicodeWriter *writer, int level) |
| { |
| /* Debug build: __dump__() method implementation for a node. |
| |
| This method automatically dispatches to the suitable |
| hamt_node_{nodetype})_dump method. |
| */ |
| |
| if (IS_BITMAP_NODE(node)) { |
| return hamt_node_bitmap_dump( |
| (PyHamtNode_Bitmap *)node, writer, level); |
| } |
| else if (IS_ARRAY_NODE(node)) { |
| return hamt_node_array_dump( |
| (PyHamtNode_Array *)node, writer, level); |
| } |
| else { |
| assert(IS_COLLISION_NODE(node)); |
| return hamt_node_collision_dump( |
| (PyHamtNode_Collision *)node, writer, level); |
| } |
| } |
| #endif /* Py_DEBUG */ |
| |
| |
| /////////////////////////////////// Iterators: Machinery |
| |
| |
| static hamt_iter_t |
| hamt_iterator_next(PyHamtIteratorState *iter, PyObject **key, PyObject **val); |
| |
| |
| static void |
| hamt_iterator_init(PyHamtIteratorState *iter, PyHamtNode *root) |
| { |
| for (uint32_t i = 0; i < _Py_HAMT_MAX_TREE_DEPTH; i++) { |
| iter->i_nodes[i] = NULL; |
| iter->i_pos[i] = 0; |
| } |
| |
| iter->i_level = 0; |
| |
| /* Note: we don't incref/decref nodes in i_nodes. */ |
| iter->i_nodes[0] = root; |
| } |
| |
| static hamt_iter_t |
| hamt_iterator_bitmap_next(PyHamtIteratorState *iter, |
| PyObject **key, PyObject **val) |
| { |
| int8_t level = iter->i_level; |
| |
| PyHamtNode_Bitmap *node = (PyHamtNode_Bitmap *)(iter->i_nodes[level]); |
| Py_ssize_t pos = iter->i_pos[level]; |
| |
| if (pos + 1 >= Py_SIZE(node)) { |
| #ifdef Py_DEBUG |
| assert(iter->i_level >= 0); |
| iter->i_nodes[iter->i_level] = NULL; |
| #endif |
| iter->i_level--; |
| return hamt_iterator_next(iter, key, val); |
| } |
| |
| if (node->b_array[pos] == NULL) { |
| iter->i_pos[level] = pos + 2; |
| |
| int8_t next_level = level + 1; |
| assert(next_level < _Py_HAMT_MAX_TREE_DEPTH); |
| iter->i_level = next_level; |
| iter->i_pos[next_level] = 0; |
| iter->i_nodes[next_level] = (PyHamtNode *) |
| node->b_array[pos + 1]; |
| |
| return hamt_iterator_next(iter, key, val); |
| } |
| |
| *key = node->b_array[pos]; |
| *val = node->b_array[pos + 1]; |
| iter->i_pos[level] = pos + 2; |
| return I_ITEM; |
| } |
| |
| static hamt_iter_t |
| hamt_iterator_collision_next(PyHamtIteratorState *iter, |
| PyObject **key, PyObject **val) |
| { |
| int8_t level = iter->i_level; |
| |
| PyHamtNode_Collision *node = (PyHamtNode_Collision *)(iter->i_nodes[level]); |
| Py_ssize_t pos = iter->i_pos[level]; |
| |
| if (pos + 1 >= Py_SIZE(node)) { |
| #ifdef Py_DEBUG |
| assert(iter->i_level >= 0); |
| iter->i_nodes[iter->i_level] = NULL; |
| #endif |
| iter->i_level--; |
| return hamt_iterator_next(iter, key, val); |
| } |
| |
| *key = node->c_array[pos]; |
| *val = node->c_array[pos + 1]; |
| iter->i_pos[level] = pos + 2; |
| return I_ITEM; |
| } |
| |
| static hamt_iter_t |
| hamt_iterator_array_next(PyHamtIteratorState *iter, |
| PyObject **key, PyObject **val) |
| { |
| int8_t level = iter->i_level; |
| |
| PyHamtNode_Array *node = (PyHamtNode_Array *)(iter->i_nodes[level]); |
| Py_ssize_t pos = iter->i_pos[level]; |
| |
| if (pos >= HAMT_ARRAY_NODE_SIZE) { |
| #ifdef Py_DEBUG |
| assert(iter->i_level >= 0); |
| iter->i_nodes[iter->i_level] = NULL; |
| #endif |
| iter->i_level--; |
| return hamt_iterator_next(iter, key, val); |
| } |
| |
| for (Py_ssize_t i = pos; i < HAMT_ARRAY_NODE_SIZE; i++) { |
| if (node->a_array[i] != NULL) { |
| iter->i_pos[level] = i + 1; |
| |
| int8_t next_level = level + 1; |
| assert(next_level < _Py_HAMT_MAX_TREE_DEPTH); |
| iter->i_pos[next_level] = 0; |
| iter->i_nodes[next_level] = node->a_array[i]; |
| iter->i_level = next_level; |
| |
| return hamt_iterator_next(iter, key, val); |
| } |
| } |
| |
| #ifdef Py_DEBUG |
| assert(iter->i_level >= 0); |
| iter->i_nodes[iter->i_level] = NULL; |
| #endif |
| |
| iter->i_level--; |
| return hamt_iterator_next(iter, key, val); |
| } |
| |
| static hamt_iter_t |
| hamt_iterator_next(PyHamtIteratorState *iter, PyObject **key, PyObject **val) |
| { |
| if (iter->i_level < 0) { |
| return I_END; |
| } |
| |
| assert(iter->i_level < _Py_HAMT_MAX_TREE_DEPTH); |
| |
| PyHamtNode *current = iter->i_nodes[iter->i_level]; |
| |
| if (IS_BITMAP_NODE(current)) { |
| return hamt_iterator_bitmap_next(iter, key, val); |
| } |
| else if (IS_ARRAY_NODE(current)) { |
| return hamt_iterator_array_next(iter, key, val); |
| } |
| else { |
| assert(IS_COLLISION_NODE(current)); |
| return hamt_iterator_collision_next(iter, key, val); |
| } |
| } |
| |
| |
| /////////////////////////////////// HAMT high-level functions |
| |
| |
| PyHamtObject * |
| _PyHamt_Assoc(PyHamtObject *o, PyObject *key, PyObject *val) |
| { |
| int32_t key_hash; |
| int added_leaf = 0; |
| PyHamtNode *new_root; |
| PyHamtObject *new_o; |
| |
| key_hash = hamt_hash(key); |
| if (key_hash == -1) { |
| return NULL; |
| } |
| |
| new_root = hamt_node_assoc( |
| (PyHamtNode *)(o->h_root), |
| 0, key_hash, key, val, &added_leaf); |
| if (new_root == NULL) { |
| return NULL; |
| } |
| |
| if (new_root == o->h_root) { |
| Py_DECREF(new_root); |
| Py_INCREF(o); |
| return o; |
| } |
| |
| new_o = hamt_alloc(); |
| if (new_o == NULL) { |
| Py_DECREF(new_root); |
| return NULL; |
| } |
| |
| new_o->h_root = new_root; /* borrow */ |
| new_o->h_count = added_leaf ? o->h_count + 1 : o->h_count; |
| |
| return new_o; |
| } |
| |
| PyHamtObject * |
| _PyHamt_Without(PyHamtObject *o, PyObject *key) |
| { |
| int32_t key_hash = hamt_hash(key); |
| if (key_hash == -1) { |
| return NULL; |
| } |
| |
| PyHamtNode *new_root = NULL; |
| |
| hamt_without_t res = hamt_node_without( |
| (PyHamtNode *)(o->h_root), |
| 0, key_hash, key, |
| &new_root); |
| |
| switch (res) { |
| case W_ERROR: |
| return NULL; |
| case W_EMPTY: |
| return _PyHamt_New(); |
| case W_NOT_FOUND: |
| Py_INCREF(o); |
| return o; |
| case W_NEWNODE: { |
| assert(new_root != NULL); |
| |
| PyHamtObject *new_o = hamt_alloc(); |
| if (new_o == NULL) { |
| Py_DECREF(new_root); |
| return NULL; |
| } |
| |
| new_o->h_root = new_root; /* borrow */ |
| new_o->h_count = o->h_count - 1; |
| assert(new_o->h_count >= 0); |
| return new_o; |
| } |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| |
| static hamt_find_t |
| hamt_find(PyHamtObject *o, PyObject *key, PyObject **val) |
| { |
| if (o->h_count == 0) { |
| return F_NOT_FOUND; |
| } |
| |
| int32_t key_hash = hamt_hash(key); |
| if (key_hash == -1) { |
| return F_ERROR; |
| } |
| |
| return hamt_node_find(o->h_root, 0, key_hash, key, val); |
| } |
| |
| |
| int |
| _PyHamt_Find(PyHamtObject *o, PyObject *key, PyObject **val) |
| { |
| hamt_find_t res = hamt_find(o, key, val); |
| switch (res) { |
| case F_ERROR: |
| return -1; |
| case F_NOT_FOUND: |
| return 0; |
| case F_FOUND: |
| return 1; |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| |
| |
| int |
| _PyHamt_Eq(PyHamtObject *v, PyHamtObject *w) |
| { |
| if (v == w) { |
| return 1; |
| } |
| |
| if (v->h_count != w->h_count) { |
| return 0; |
| } |
| |
| PyHamtIteratorState iter; |
| hamt_iter_t iter_res; |
| hamt_find_t find_res; |
| PyObject *v_key; |
| PyObject *v_val; |
| PyObject *w_val; |
| |
| hamt_iterator_init(&iter, v->h_root); |
| |
| do { |
| iter_res = hamt_iterator_next(&iter, &v_key, &v_val); |
| if (iter_res == I_ITEM) { |
| find_res = hamt_find(w, v_key, &w_val); |
| switch (find_res) { |
| case F_ERROR: |
| return -1; |
| |
| case F_NOT_FOUND: |
| return 0; |
| |
| case F_FOUND: { |
| int cmp = PyObject_RichCompareBool(v_val, w_val, Py_EQ); |
| if (cmp < 0) { |
| return -1; |
| } |
| if (cmp == 0) { |
| return 0; |
| } |
| } |
| } |
| } |
| } while (iter_res != I_END); |
| |
| return 1; |
| } |
| |
| Py_ssize_t |
| _PyHamt_Len(PyHamtObject *o) |
| { |
| return o->h_count; |
| } |
| |
| static PyHamtObject * |
| hamt_alloc(void) |
| { |
| PyHamtObject *o; |
| o = PyObject_GC_New(PyHamtObject, &_PyHamt_Type); |
| if (o == NULL) { |
| return NULL; |
| } |
| o->h_count = 0; |
| o->h_root = NULL; |
| o->h_weakreflist = NULL; |
| PyObject_GC_Track(o); |
| return o; |
| } |
| |
| PyHamtObject * |
| _PyHamt_New(void) |
| { |
| if (_empty_hamt != NULL) { |
| /* HAMT is an immutable object so we can easily cache an |
| empty instance. */ |
| Py_INCREF(_empty_hamt); |
| return _empty_hamt; |
| } |
| |
| PyHamtObject *o = hamt_alloc(); |
| if (o == NULL) { |
| return NULL; |
| } |
| |
| o->h_root = hamt_node_bitmap_new(0); |
| if (o->h_root == NULL) { |
| Py_DECREF(o); |
| return NULL; |
| } |
| |
| o->h_count = 0; |
| |
| if (_empty_hamt == NULL) { |
| Py_INCREF(o); |
| _empty_hamt = o; |
| } |
| |
| return o; |
| } |
| |
| #ifdef Py_DEBUG |
| static PyObject * |
| hamt_dump(PyHamtObject *self) |
| { |
| _PyUnicodeWriter writer; |
| |
| _PyUnicodeWriter_Init(&writer); |
| |
| if (_hamt_dump_format(&writer, "HAMT(len=%zd):\n", self->h_count)) { |
| goto error; |
| } |
| |
| if (hamt_node_dump(self->h_root, &writer, 0)) { |
| goto error; |
| } |
| |
| return _PyUnicodeWriter_Finish(&writer); |
| |
| error: |
| _PyUnicodeWriter_Dealloc(&writer); |
| return NULL; |
| } |
| #endif /* Py_DEBUG */ |
| |
| |
| /////////////////////////////////// Iterators: Shared Iterator Implementation |
| |
| |
| static int |
| hamt_baseiter_tp_clear(PyHamtIterator *it) |
| { |
| Py_CLEAR(it->hi_obj); |
| return 0; |
| } |
| |
| static void |
| hamt_baseiter_tp_dealloc(PyHamtIterator *it) |
| { |
| PyObject_GC_UnTrack(it); |
| (void)hamt_baseiter_tp_clear(it); |
| PyObject_GC_Del(it); |
| } |
| |
| static int |
| hamt_baseiter_tp_traverse(PyHamtIterator *it, visitproc visit, void *arg) |
| { |
| Py_VISIT(it->hi_obj); |
| return 0; |
| } |
| |
| static PyObject * |
| hamt_baseiter_tp_iternext(PyHamtIterator *it) |
| { |
| PyObject *key; |
| PyObject *val; |
| hamt_iter_t res = hamt_iterator_next(&it->hi_iter, &key, &val); |
| |
| switch (res) { |
| case I_END: |
| PyErr_SetNone(PyExc_StopIteration); |
| return NULL; |
| |
| case I_ITEM: { |
| return (*(it->hi_yield))(key, val); |
| } |
| |
| default: { |
| Py_UNREACHABLE(); |
| } |
| } |
| } |
| |
| static Py_ssize_t |
| hamt_baseiter_tp_len(PyHamtIterator *it) |
| { |
| return it->hi_obj->h_count; |
| } |
| |
| static PyMappingMethods PyHamtIterator_as_mapping = { |
| (lenfunc)hamt_baseiter_tp_len, |
| }; |
| |
| static PyObject * |
| hamt_baseiter_new(PyTypeObject *type, binaryfunc yield, PyHamtObject *o) |
| { |
| PyHamtIterator *it = PyObject_GC_New(PyHamtIterator, type); |
| if (it == NULL) { |
| return NULL; |
| } |
| |
| Py_INCREF(o); |
| it->hi_obj = o; |
| it->hi_yield = yield; |
| |
| hamt_iterator_init(&it->hi_iter, o->h_root); |
| |
| return (PyObject*)it; |
| } |
| |
| #define ITERATOR_TYPE_SHARED_SLOTS \ |
| .tp_basicsize = sizeof(PyHamtIterator), \ |
| .tp_itemsize = 0, \ |
| .tp_as_mapping = &PyHamtIterator_as_mapping, \ |
| .tp_dealloc = (destructor)hamt_baseiter_tp_dealloc, \ |
| .tp_getattro = PyObject_GenericGetAttr, \ |
| .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, \ |
| .tp_traverse = (traverseproc)hamt_baseiter_tp_traverse, \ |
| .tp_clear = (inquiry)hamt_baseiter_tp_clear, \ |
| .tp_iter = PyObject_SelfIter, \ |
| .tp_iternext = (iternextfunc)hamt_baseiter_tp_iternext, |
| |
| |
| /////////////////////////////////// _PyHamtItems_Type |
| |
| |
| PyTypeObject _PyHamtItems_Type = { |
| PyVarObject_HEAD_INIT(NULL, 0) |
| "items", |
| ITERATOR_TYPE_SHARED_SLOTS |
| }; |
| |
| static PyObject * |
| hamt_iter_yield_items(PyObject *key, PyObject *val) |
| { |
| return PyTuple_Pack(2, key, val); |
| } |
| |
| PyObject * |
| _PyHamt_NewIterItems(PyHamtObject *o) |
| { |
| return hamt_baseiter_new( |
| &_PyHamtItems_Type, hamt_iter_yield_items, o); |
| } |
| |
| |
| /////////////////////////////////// _PyHamtKeys_Type |
| |
| |
| PyTypeObject _PyHamtKeys_Type = { |
| PyVarObject_HEAD_INIT(NULL, 0) |
| "keys", |
| ITERATOR_TYPE_SHARED_SLOTS |
| }; |
| |
| static PyObject * |
| hamt_iter_yield_keys(PyObject *key, PyObject *val) |
| { |
| Py_INCREF(key); |
| return key; |
| } |
| |
| PyObject * |
| _PyHamt_NewIterKeys(PyHamtObject *o) |
| { |
| return hamt_baseiter_new( |
| &_PyHamtKeys_Type, hamt_iter_yield_keys, o); |
| } |
| |
| |
| /////////////////////////////////// _PyHamtValues_Type |
| |
| |
| PyTypeObject _PyHamtValues_Type = { |
| PyVarObject_HEAD_INIT(NULL, 0) |
| "values", |
| ITERATOR_TYPE_SHARED_SLOTS |
| }; |
| |
| static PyObject * |
| hamt_iter_yield_values(PyObject *key, PyObject *val) |
| { |
| Py_INCREF(val); |
| return val; |
| } |
| |
| PyObject * |
| _PyHamt_NewIterValues(PyHamtObject *o) |
| { |
| return hamt_baseiter_new( |
| &_PyHamtValues_Type, hamt_iter_yield_values, o); |
| } |
| |
| |
| /////////////////////////////////// _PyHamt_Type |
| |
| |
| #ifdef Py_DEBUG |
| static PyObject * |
| hamt_dump(PyHamtObject *self); |
| #endif |
| |
| |
| static PyObject * |
| hamt_tp_new(PyTypeObject *type, PyObject *args, PyObject *kwds) |
| { |
| return (PyObject*)_PyHamt_New(); |
| } |
| |
| static int |
| hamt_tp_clear(PyHamtObject *self) |
| { |
| Py_CLEAR(self->h_root); |
| return 0; |
| } |
| |
| |
| static int |
| hamt_tp_traverse(PyHamtObject *self, visitproc visit, void *arg) |
| { |
| Py_VISIT(self->h_root); |
| return 0; |
| } |
| |
| static void |
| hamt_tp_dealloc(PyHamtObject *self) |
| { |
| PyObject_GC_UnTrack(self); |
| if (self->h_weakreflist != NULL) { |
| PyObject_ClearWeakRefs((PyObject*)self); |
| } |
| (void)hamt_tp_clear(self); |
| Py_TYPE(self)->tp_free(self); |
| } |
| |
| |
| static PyObject * |
| hamt_tp_richcompare(PyObject *v, PyObject *w, int op) |
| { |
| if (!PyHamt_Check(v) || !PyHamt_Check(w) || (op != Py_EQ && op != Py_NE)) { |
| Py_RETURN_NOTIMPLEMENTED; |
| } |
| |
| int res = _PyHamt_Eq((PyHamtObject *)v, (PyHamtObject *)w); |
| if (res < 0) { |
| return NULL; |
| } |
| |
| if (op == Py_NE) { |
| res = !res; |
| } |
| |
| if (res) { |
| Py_RETURN_TRUE; |
| } |
| else { |
| Py_RETURN_FALSE; |
| } |
| } |
| |
| static int |
| hamt_tp_contains(PyHamtObject *self, PyObject *key) |
| { |
| PyObject *val; |
| return _PyHamt_Find(self, key, &val); |
| } |
| |
| static PyObject * |
| hamt_tp_subscript(PyHamtObject *self, PyObject *key) |
| { |
| PyObject *val; |
| hamt_find_t res = hamt_find(self, key, &val); |
| switch (res) { |
| case F_ERROR: |
| return NULL; |
| case F_FOUND: |
| Py_INCREF(val); |
| return val; |
| case F_NOT_FOUND: |
| PyErr_SetObject(PyExc_KeyError, key); |
| return NULL; |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| |
| static Py_ssize_t |
| hamt_tp_len(PyHamtObject *self) |
| { |
| return _PyHamt_Len(self); |
| } |
| |
| static PyObject * |
| hamt_tp_iter(PyHamtObject *self) |
| { |
| return _PyHamt_NewIterKeys(self); |
| } |
| |
| static PyObject * |
| hamt_py_set(PyHamtObject *self, PyObject *args) |
| { |
| PyObject *key; |
| PyObject *val; |
| |
| if (!PyArg_UnpackTuple(args, "set", 2, 2, &key, &val)) { |
| return NULL; |
| } |
| |
| return (PyObject *)_PyHamt_Assoc(self, key, val); |
| } |
| |
| static PyObject * |
| hamt_py_get(PyHamtObject *self, PyObject *args) |
| { |
| PyObject *key; |
| PyObject *def = NULL; |
| |
| if (!PyArg_UnpackTuple(args, "get", 1, 2, &key, &def)) { |
| return NULL; |
| } |
| |
| PyObject *val = NULL; |
| hamt_find_t res = hamt_find(self, key, &val); |
| switch (res) { |
| case F_ERROR: |
| return NULL; |
| case F_FOUND: |
| Py_INCREF(val); |
| return val; |
| case F_NOT_FOUND: |
| if (def == NULL) { |
| Py_RETURN_NONE; |
| } |
| Py_INCREF(def); |
| return def; |
| default: |
| Py_UNREACHABLE(); |
| } |
| } |
| |
| static PyObject * |
| hamt_py_delete(PyHamtObject *self, PyObject *key) |
| { |
| return (PyObject *)_PyHamt_Without(self, key); |
| } |
| |
| static PyObject * |
| hamt_py_items(PyHamtObject *self, PyObject *args) |
| { |
| return _PyHamt_NewIterItems(self); |
| } |
| |
| static PyObject * |
| hamt_py_values(PyHamtObject *self, PyObject *args) |
| { |
| return _PyHamt_NewIterValues(self); |
| } |
| |
| static PyObject * |
| hamt_py_keys(PyHamtObject *self, PyObject *args) |
| { |
| return _PyHamt_NewIterKeys(self); |
| } |
| |
| #ifdef Py_DEBUG |
| static PyObject * |
| hamt_py_dump(PyHamtObject *self, PyObject *args) |
| { |
| return hamt_dump(self); |
| } |
| #endif |
| |
| |
| static PyMethodDef PyHamt_methods[] = { |
| {"set", (PyCFunction)hamt_py_set, METH_VARARGS, NULL}, |
| {"get", (PyCFunction)hamt_py_get, METH_VARARGS, NULL}, |
| {"delete", (PyCFunction)hamt_py_delete, METH_O, NULL}, |
| {"items", (PyCFunction)hamt_py_items, METH_NOARGS, NULL}, |
| {"keys", (PyCFunction)hamt_py_keys, METH_NOARGS, NULL}, |
| {"values", (PyCFunction)hamt_py_values, METH_NOARGS, NULL}, |
| #ifdef Py_DEBUG |
| {"__dump__", (PyCFunction)hamt_py_dump, METH_NOARGS, NULL}, |
| #endif |
| {NULL, NULL} |
| }; |
| |
| static PySequenceMethods PyHamt_as_sequence = { |
| 0, /* sq_length */ |
| 0, /* sq_concat */ |
| 0, /* sq_repeat */ |
| 0, /* sq_item */ |
| 0, /* sq_slice */ |
| 0, /* sq_ass_item */ |
| 0, /* sq_ass_slice */ |
| (objobjproc)hamt_tp_contains, /* sq_contains */ |
| 0, /* sq_inplace_concat */ |
| 0, /* sq_inplace_repeat */ |
| }; |
| |
| static PyMappingMethods PyHamt_as_mapping = { |
| (lenfunc)hamt_tp_len, /* mp_length */ |
| (binaryfunc)hamt_tp_subscript, /* mp_subscript */ |
| }; |
| |
| PyTypeObject _PyHamt_Type = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "hamt", |
| sizeof(PyHamtObject), |
| .tp_methods = PyHamt_methods, |
| .tp_as_mapping = &PyHamt_as_mapping, |
| .tp_as_sequence = &PyHamt_as_sequence, |
| .tp_iter = (getiterfunc)hamt_tp_iter, |
| .tp_dealloc = (destructor)hamt_tp_dealloc, |
| .tp_getattro = PyObject_GenericGetAttr, |
| .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, |
| .tp_richcompare = hamt_tp_richcompare, |
| .tp_traverse = (traverseproc)hamt_tp_traverse, |
| .tp_clear = (inquiry)hamt_tp_clear, |
| .tp_new = hamt_tp_new, |
| .tp_weaklistoffset = offsetof(PyHamtObject, h_weakreflist), |
| .tp_hash = PyObject_HashNotImplemented, |
| }; |
| |
| |
| /////////////////////////////////// Tree Node Types |
| |
| |
| PyTypeObject _PyHamt_ArrayNode_Type = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "hamt_array_node", |
| sizeof(PyHamtNode_Array), |
| 0, |
| .tp_dealloc = (destructor)hamt_node_array_dealloc, |
| .tp_getattro = PyObject_GenericGetAttr, |
| .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, |
| .tp_traverse = (traverseproc)hamt_node_array_traverse, |
| .tp_free = PyObject_GC_Del, |
| .tp_hash = PyObject_HashNotImplemented, |
| }; |
| |
| PyTypeObject _PyHamt_BitmapNode_Type = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "hamt_bitmap_node", |
| sizeof(PyHamtNode_Bitmap) - sizeof(PyObject *), |
| sizeof(PyObject *), |
| .tp_dealloc = (destructor)hamt_node_bitmap_dealloc, |
| .tp_getattro = PyObject_GenericGetAttr, |
| .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, |
| .tp_traverse = (traverseproc)hamt_node_bitmap_traverse, |
| .tp_free = PyObject_GC_Del, |
| .tp_hash = PyObject_HashNotImplemented, |
| }; |
| |
| PyTypeObject _PyHamt_CollisionNode_Type = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "hamt_collision_node", |
| sizeof(PyHamtNode_Collision) - sizeof(PyObject *), |
| sizeof(PyObject *), |
| .tp_dealloc = (destructor)hamt_node_collision_dealloc, |
| .tp_getattro = PyObject_GenericGetAttr, |
| .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_HAVE_GC, |
| .tp_traverse = (traverseproc)hamt_node_collision_traverse, |
| .tp_free = PyObject_GC_Del, |
| .tp_hash = PyObject_HashNotImplemented, |
| }; |
| |
| |
| int |
| _PyHamt_Init(void) |
| { |
| if ((PyType_Ready(&_PyHamt_Type) < 0) || |
| (PyType_Ready(&_PyHamt_ArrayNode_Type) < 0) || |
| (PyType_Ready(&_PyHamt_BitmapNode_Type) < 0) || |
| (PyType_Ready(&_PyHamt_CollisionNode_Type) < 0) || |
| (PyType_Ready(&_PyHamtKeys_Type) < 0) || |
| (PyType_Ready(&_PyHamtValues_Type) < 0) || |
| (PyType_Ready(&_PyHamtItems_Type) < 0)) |
| { |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| void |
| _PyHamt_Fini(void) |
| { |
| Py_CLEAR(_empty_hamt); |
| Py_CLEAR(_empty_bitmap_node); |
| } |