diff options
Diffstat (limited to 'shape.h')
| -rw-r--r-- | shape.h | 484 |
1 files changed, 484 insertions, 0 deletions
diff --git a/shape.h b/shape.h new file mode 100644 index 0000000000..96c78f2bc1 --- /dev/null +++ b/shape.h @@ -0,0 +1,484 @@ +#ifndef RUBY_SHAPE_H +#define RUBY_SHAPE_H + +#include "internal/gc.h" +#include "internal/struct.h" + +typedef uint16_t attr_index_t; +typedef uint32_t shape_id_t; +#define SHAPE_ID_NUM_BITS 32 +#define SHAPE_ID_OFFSET_NUM_BITS 19 + +STATIC_ASSERT(shape_id_num_bits, SHAPE_ID_NUM_BITS == sizeof(shape_id_t) * CHAR_BIT); + +#define SHAPE_BUFFER_SIZE (1 << SHAPE_ID_OFFSET_NUM_BITS) +#define SHAPE_ID_OFFSET_MASK (SHAPE_BUFFER_SIZE - 1) + +#define SHAPE_ID_HEAP_INDEX_BITS 3 +#define SHAPE_ID_HEAP_INDEX_MAX ((1 << SHAPE_ID_HEAP_INDEX_BITS) - 1) + +#define SHAPE_ID_FL_USHIFT (SHAPE_ID_OFFSET_NUM_BITS + SHAPE_ID_HEAP_INDEX_BITS) +#define SHAPE_ID_HEAP_INDEX_OFFSET SHAPE_ID_FL_USHIFT + +// shape_id_t bits: +// 0-18 SHAPE_ID_OFFSET_MASK +// index in rb_shape_tree.shape_list. Allow to access `rb_shape_t *`. +// 19-21 SHAPE_ID_HEAP_INDEX_MASK +// index in rb_shape_tree.capacities. Allow to access slot size. +// Always 0 except for T_OBJECT. +// 22 SHAPE_ID_FL_FROZEN +// Whether the object is frozen or not. +// 23 SHAPE_ID_FL_HAS_OBJECT_ID +// Whether the object has an `SHAPE_OBJ_ID` transition. +// 24 SHAPE_ID_FL_TOO_COMPLEX +// The object is backed by a `st_table`. + +enum shape_id_fl_type { +#define RBIMPL_SHAPE_ID_FL(n) (1<<(SHAPE_ID_FL_USHIFT+n)) + + SHAPE_ID_HEAP_INDEX_MASK = RBIMPL_SHAPE_ID_FL(0) | RBIMPL_SHAPE_ID_FL(1) | RBIMPL_SHAPE_ID_FL(2), + + SHAPE_ID_FL_FROZEN = RBIMPL_SHAPE_ID_FL(3), + SHAPE_ID_FL_HAS_OBJECT_ID = RBIMPL_SHAPE_ID_FL(4), + SHAPE_ID_FL_TOO_COMPLEX = RBIMPL_SHAPE_ID_FL(5), + + SHAPE_ID_FL_NON_CANONICAL_MASK = SHAPE_ID_FL_FROZEN | SHAPE_ID_FL_HAS_OBJECT_ID, + SHAPE_ID_FLAGS_MASK = SHAPE_ID_HEAP_INDEX_MASK | SHAPE_ID_FL_NON_CANONICAL_MASK | SHAPE_ID_FL_TOO_COMPLEX, + +#undef RBIMPL_SHAPE_ID_FL +}; + +// This mask allows to check if a shape_id contains any ivar. +// It relies on ROOT_SHAPE_WITH_OBJ_ID==1. +enum shape_id_mask { + SHAPE_ID_HAS_IVAR_MASK = SHAPE_ID_FL_TOO_COMPLEX | (SHAPE_ID_OFFSET_MASK - 1), +}; + +// The interpreter doesn't care about frozen status or slot size when reading ivars. +// So we normalize shape_id by clearing these bits to improve cache hits. +// JITs however might care about it. +#define SHAPE_ID_READ_ONLY_MASK (~(SHAPE_ID_FL_FROZEN | SHAPE_ID_HEAP_INDEX_MASK)) + +typedef uint32_t redblack_id_t; + +#define SHAPE_MAX_FIELDS (attr_index_t)(-1) +#define SHAPE_FLAG_SHIFT ((SIZEOF_VALUE * CHAR_BIT) - SHAPE_ID_NUM_BITS) +#define SHAPE_FLAG_MASK (((VALUE)-1) >> SHAPE_ID_NUM_BITS) + +#define SHAPE_MAX_VARIATIONS 8 + +#define INVALID_SHAPE_ID ((shape_id_t)-1) +#define ATTR_INDEX_NOT_SET ((attr_index_t)-1) + +#define ROOT_SHAPE_ID 0x0 +#define ROOT_SHAPE_WITH_OBJ_ID 0x1 +#define ROOT_TOO_COMPLEX_SHAPE_ID (ROOT_SHAPE_ID | SHAPE_ID_FL_TOO_COMPLEX) +#define ROOT_TOO_COMPLEX_WITH_OBJ_ID (ROOT_SHAPE_WITH_OBJ_ID | SHAPE_ID_FL_TOO_COMPLEX | SHAPE_ID_FL_HAS_OBJECT_ID) + +typedef struct redblack_node redblack_node_t; + +struct rb_shape { + VALUE edges; // id_table from ID (ivar) to next shape + ID edge_name; // ID (ivar) for transition from parent to rb_shape + redblack_node_t *ancestor_index; + shape_id_t parent_id; + attr_index_t next_field_index; // Fields are either ivars or internal properties like `object_id` + attr_index_t capacity; // Total capacity of the object with this shape + uint8_t type; +}; + +typedef struct rb_shape rb_shape_t; + +struct redblack_node { + ID key; + rb_shape_t *value; + redblack_id_t l; + redblack_id_t r; +}; + +enum shape_type { + SHAPE_ROOT, + SHAPE_IVAR, + SHAPE_OBJ_ID, +}; + +enum shape_flags { + SHAPE_FL_FROZEN = 1 << 0, + SHAPE_FL_HAS_OBJECT_ID = 1 << 1, + SHAPE_FL_TOO_COMPLEX = 1 << 2, + + SHAPE_FL_NON_CANONICAL_MASK = SHAPE_FL_FROZEN | SHAPE_FL_HAS_OBJECT_ID, +}; + +typedef struct { + /* object shapes */ + rb_shape_t *shape_list; + rb_shape_t *root_shape; + const attr_index_t *capacities; + rb_atomic_t next_shape_id; + + redblack_node_t *shape_cache; + unsigned int cache_size; +} rb_shape_tree_t; + +RUBY_SYMBOL_EXPORT_BEGIN +RUBY_EXTERN rb_shape_tree_t rb_shape_tree; +RUBY_SYMBOL_EXPORT_END + +static inline shape_id_t +rb_shapes_count(void) +{ + return (shape_id_t)RUBY_ATOMIC_LOAD(rb_shape_tree.next_shape_id); +} + +union rb_attr_index_cache { + uint64_t pack; + struct { + shape_id_t shape_id; + attr_index_t index; + } unpack; +}; + +static inline shape_id_t +RBASIC_SHAPE_ID(VALUE obj) +{ + RUBY_ASSERT(!RB_SPECIAL_CONST_P(obj)); + RUBY_ASSERT(!RB_TYPE_P(obj, T_IMEMO) || IMEMO_TYPE_P(obj, imemo_fields)); +#if RBASIC_SHAPE_ID_FIELD + return (shape_id_t)((RBASIC(obj)->shape_id)); +#else + return (shape_id_t)((RBASIC(obj)->flags) >> SHAPE_FLAG_SHIFT); +#endif +} + +// Same as RBASIC_SHAPE_ID but with flags that have no impact +// on reads removed. e.g. Remove FL_FROZEN. +static inline shape_id_t +RBASIC_SHAPE_ID_FOR_READ(VALUE obj) +{ + return RBASIC_SHAPE_ID(obj) & SHAPE_ID_READ_ONLY_MASK; +} + +#if RUBY_DEBUG +bool rb_shape_verify_consistency(VALUE obj, shape_id_t shape_id); +#endif + +static inline void +RBASIC_SET_SHAPE_ID_NO_CHECKS(VALUE obj, shape_id_t shape_id) +{ +#if RBASIC_SHAPE_ID_FIELD + RBASIC(obj)->shape_id = (VALUE)shape_id; +#else + // Object shapes are occupying top bits + RBASIC(obj)->flags &= SHAPE_FLAG_MASK; + RBASIC(obj)->flags |= ((VALUE)(shape_id) << SHAPE_FLAG_SHIFT); +#endif +} + +static inline void +RBASIC_SET_SHAPE_ID(VALUE obj, shape_id_t shape_id) +{ + RUBY_ASSERT(!RB_SPECIAL_CONST_P(obj)); + RUBY_ASSERT(!RB_TYPE_P(obj, T_IMEMO) || IMEMO_TYPE_P(obj, imemo_fields)); + + RBASIC_SET_SHAPE_ID_NO_CHECKS(obj, shape_id); + + RUBY_ASSERT(rb_shape_verify_consistency(obj, shape_id)); +} + +void rb_set_boxed_class_shape_id(VALUE obj, shape_id_t shape_id); + +static inline void +RB_SET_SHAPE_ID(VALUE obj, shape_id_t shape_id) +{ + switch (BUILTIN_TYPE(obj)) { + case T_CLASS: + case T_MODULE: + rb_set_boxed_class_shape_id(obj, shape_id); + break; + default: + RBASIC_SET_SHAPE_ID(obj, shape_id); + break; + } +} + +static inline rb_shape_t * +RSHAPE(shape_id_t shape_id) +{ + uint32_t offset = (shape_id & SHAPE_ID_OFFSET_MASK); + RUBY_ASSERT(offset != INVALID_SHAPE_ID); + + return &rb_shape_tree.shape_list[offset]; +} + +int32_t rb_shape_id_offset(void); + +RUBY_FUNC_EXPORTED shape_id_t rb_obj_shape_id(VALUE obj); +shape_id_t rb_shape_get_next_iv_shape(shape_id_t shape_id, ID id); +bool rb_shape_get_iv_index(shape_id_t shape_id, ID id, attr_index_t *value); +bool rb_shape_get_iv_index_with_hint(shape_id_t shape_id, ID id, attr_index_t *value, shape_id_t *shape_id_hint); +bool rb_shape_find_ivar(shape_id_t shape_id, ID id, shape_id_t *ivar_shape); + +typedef int rb_shape_foreach_transition_callback(shape_id_t shape_id, void *data); +bool rb_shape_foreach_field(shape_id_t shape_id, rb_shape_foreach_transition_callback func, void *data); + +shape_id_t rb_shape_transition_frozen(VALUE obj); +shape_id_t rb_shape_transition_complex(VALUE obj); +shape_id_t rb_shape_transition_remove_ivar(VALUE obj, ID id, shape_id_t *removed_shape_id); +shape_id_t rb_shape_transition_add_ivar(VALUE obj, ID id); +shape_id_t rb_shape_transition_add_ivar_no_warnings(VALUE klass, shape_id_t original_shape_id, ID id); +shape_id_t rb_shape_transition_object_id(VALUE obj); +shape_id_t rb_shape_transition_heap(VALUE obj, size_t heap_index); +shape_id_t rb_shape_object_id(shape_id_t original_shape_id); + +void rb_shape_free_all(void); + +shape_id_t rb_shape_rebuild(shape_id_t initial_shape_id, shape_id_t dest_shape_id); +void rb_shape_copy_fields(VALUE dest, VALUE *dest_buf, shape_id_t dest_shape_id, VALUE *src_buf, shape_id_t src_shape_id); +void rb_shape_copy_complex_ivars(VALUE dest, VALUE obj, shape_id_t src_shape_id, st_table *fields_table); + +static inline bool +rb_shape_too_complex_p(shape_id_t shape_id) +{ + return shape_id & SHAPE_ID_FL_TOO_COMPLEX; +} + +static inline bool +rb_shape_obj_too_complex_p(VALUE obj) +{ + return !RB_SPECIAL_CONST_P(obj) && rb_shape_too_complex_p(RBASIC_SHAPE_ID(obj)); +} + +static inline bool +rb_shape_has_object_id(shape_id_t shape_id) +{ + return shape_id & SHAPE_ID_FL_HAS_OBJECT_ID; +} + +static inline bool +rb_shape_canonical_p(shape_id_t shape_id) +{ + return !(shape_id & SHAPE_ID_FL_NON_CANONICAL_MASK); +} + +static inline uint8_t +rb_shape_heap_index(shape_id_t shape_id) +{ + return (uint8_t)((shape_id & SHAPE_ID_HEAP_INDEX_MASK) >> SHAPE_ID_HEAP_INDEX_OFFSET); +} + +static inline shape_id_t +rb_shape_root(size_t heap_id) +{ + shape_id_t heap_index = (shape_id_t)(heap_id + 1); + shape_id_t heap_flags = heap_index << SHAPE_ID_HEAP_INDEX_OFFSET; + + RUBY_ASSERT((heap_flags & SHAPE_ID_HEAP_INDEX_MASK) == heap_flags); + RUBY_ASSERT(rb_shape_heap_index(heap_flags) == heap_index); + + return ROOT_SHAPE_ID | heap_flags; +} + +static inline shape_id_t +RSHAPE_PARENT_RAW_ID(shape_id_t shape_id) +{ + return RSHAPE(shape_id)->parent_id; +} + +static inline bool +RSHAPE_DIRECT_CHILD_P(shape_id_t parent_id, shape_id_t child_id) +{ + return (parent_id & SHAPE_ID_FLAGS_MASK) == (child_id & SHAPE_ID_FLAGS_MASK) && + RSHAPE(child_id)->parent_id == (parent_id & SHAPE_ID_OFFSET_MASK); +} + +static inline enum shape_type +RSHAPE_TYPE(shape_id_t shape_id) +{ + return RSHAPE(shape_id)->type; +} + +static inline bool +RSHAPE_TYPE_P(shape_id_t shape_id, enum shape_type type) +{ + return RSHAPE_TYPE(shape_id) == type; +} + +static inline attr_index_t +RSHAPE_EMBEDDED_CAPACITY(shape_id_t shape_id) +{ + uint8_t heap_index = rb_shape_heap_index(shape_id); + if (heap_index) { + return rb_shape_tree.capacities[heap_index - 1]; + } + return 0; +} + +static inline attr_index_t +RSHAPE_CAPACITY(shape_id_t shape_id) +{ + attr_index_t embedded_capacity = RSHAPE_EMBEDDED_CAPACITY(shape_id); + + if (embedded_capacity > RSHAPE(shape_id)->capacity) { + return embedded_capacity; + } + else { + return RSHAPE(shape_id)->capacity; + } +} + +static inline attr_index_t +RSHAPE_LEN(shape_id_t shape_id) +{ + return RSHAPE(shape_id)->next_field_index; +} + +static inline attr_index_t +RSHAPE_INDEX(shape_id_t shape_id) +{ + RUBY_ASSERT(RSHAPE_LEN(shape_id) > 0); + return RSHAPE_LEN(shape_id) - 1; +} + +static inline ID +RSHAPE_EDGE_NAME(shape_id_t shape_id) +{ + return RSHAPE(shape_id)->edge_name; +} + +static inline uint32_t +ROBJECT_FIELDS_CAPACITY(VALUE obj) +{ + RBIMPL_ASSERT_TYPE(obj, RUBY_T_OBJECT); + // Asking for capacity doesn't make sense when the object is using + // a hash table for storing instance variables + RUBY_ASSERT(!rb_shape_obj_too_complex_p(obj)); + return RSHAPE_CAPACITY(RBASIC_SHAPE_ID(obj)); +} + +static inline st_table * +ROBJECT_FIELDS_HASH(VALUE obj) +{ + RBIMPL_ASSERT_TYPE(obj, RUBY_T_OBJECT); + RUBY_ASSERT(rb_shape_obj_too_complex_p(obj)); + RUBY_ASSERT(FL_TEST_RAW(obj, ROBJECT_HEAP)); + + return (st_table *)ROBJECT(obj)->as.heap.fields; +} + +static inline void +ROBJECT_SET_FIELDS_HASH(VALUE obj, const st_table *tbl) +{ + RBIMPL_ASSERT_TYPE(obj, RUBY_T_OBJECT); + RUBY_ASSERT(rb_shape_obj_too_complex_p(obj)); + RUBY_ASSERT(FL_TEST_RAW(obj, ROBJECT_HEAP)); + + ROBJECT(obj)->as.heap.fields = (VALUE *)tbl; +} + +static inline uint32_t +ROBJECT_FIELDS_COUNT_COMPLEX(VALUE obj) +{ + return (uint32_t)rb_st_table_size(ROBJECT_FIELDS_HASH(obj)); +} + +static inline uint32_t +ROBJECT_FIELDS_COUNT_NOT_COMPLEX(VALUE obj) +{ + RBIMPL_ASSERT_TYPE(obj, RUBY_T_OBJECT); + RUBY_ASSERT(!rb_shape_obj_too_complex_p(obj)); + return RSHAPE(RBASIC_SHAPE_ID(obj))->next_field_index; +} + +static inline uint32_t +ROBJECT_FIELDS_COUNT(VALUE obj) +{ + if (rb_shape_obj_too_complex_p(obj)) { + return ROBJECT_FIELDS_COUNT_COMPLEX(obj); + } + else { + return ROBJECT_FIELDS_COUNT_NOT_COMPLEX(obj); + } +} + +static inline uint32_t +RBASIC_FIELDS_COUNT(VALUE obj) +{ + return RSHAPE(RBASIC_SHAPE_ID(obj))->next_field_index; +} + +static inline bool +rb_shape_obj_has_id(VALUE obj) +{ + return rb_shape_has_object_id(RBASIC_SHAPE_ID(obj)); +} + +static inline bool +rb_shape_has_ivars(shape_id_t shape_id) +{ + return shape_id & SHAPE_ID_HAS_IVAR_MASK; +} + +static inline bool +rb_shape_obj_has_ivars(VALUE obj) +{ + return rb_shape_has_ivars(RBASIC_SHAPE_ID(obj)); +} + +static inline bool +rb_shape_has_fields(shape_id_t shape_id) +{ + return shape_id & (SHAPE_ID_OFFSET_MASK | SHAPE_ID_FL_TOO_COMPLEX); +} + +static inline bool +rb_shape_obj_has_fields(VALUE obj) +{ + return rb_shape_has_fields(RBASIC_SHAPE_ID(obj)); +} + +static inline bool +rb_obj_gen_fields_p(VALUE obj) +{ + switch (TYPE(obj)) { + case T_NONE: + case T_OBJECT: + case T_CLASS: + case T_MODULE: + case T_IMEMO: + return false; + default: + break; + } + return rb_shape_obj_has_fields(obj); +} + +static inline bool +rb_obj_using_gen_fields_table_p(VALUE obj) +{ + switch (BUILTIN_TYPE(obj)) { + case T_DATA: + if (RTYPEDDATA_P(obj)) return false; + break; + + case T_STRUCT: + if (!FL_TEST_RAW(obj, RSTRUCT_GEN_FIELDS)) return false; + break; + + default: + break; + } + + return rb_obj_gen_fields_p(obj); +} + +// For ext/objspace +RUBY_SYMBOL_EXPORT_BEGIN +typedef void each_shape_callback(shape_id_t shape_id, void *data); +void rb_shape_each_shape_id(each_shape_callback callback, void *data); +size_t rb_shape_memsize(shape_id_t shape); +size_t rb_shape_edges_count(shape_id_t shape_id); +size_t rb_shape_depth(shape_id_t shape_id); +RUBY_SYMBOL_EXPORT_END + +#endif |