Module naga::arena

The Arena, UniqueArena, and Handle types.

To improve translator performance and reduce memory usage, most structures are stored in an Arena. An Arena<T> stores a series of T values, indexed by Handle<T> values, which are just wrappers around integer indexes. For example, a Function’s expressions are stored in an Arena<Expression>, and compound expressions refer to their sub-expressions via Handle<Expression> values. (When examining the serialized form of a Module, note that the first element of an Arena has an index of 1, not 0.)

A UniqueArena is just like an Arena, except that it stores only a single instance of each value. The value type must implement Eq and Hash. Like an Arena, inserting a value into a UniqueArena returns a Handle which can be used to efficiently access the value, without a hash lookup. Inserting a value multiple times returns the same Handle.

If the span feature is enabled, both Arena and UniqueArena can associate a source code span with each element.

Re-exports

• pub use handle::BadHandle;
• pub use handle::Handle;
• pub use range::BadRangeError;
• pub use range::Range;
• pub use unique_arena::UniqueArena;

Modules

• handle 🔒
  Well-typed indices into Arenas and UniqueArenas.
• handle_set 🔒
  The HandleSet type and associated definitions.
• handlevec 🔒
  The HandleVec type and associated definitions.
• range 🔒
  Well-typed ranges of Arenas.
• unique_arena 🔒
  The UniqueArena type and supporting definitions.

Structs

• Arena
  An arena holding some kind of component (e.g., type, constant, instruction, etc.) that can be referenced.