92 lines
3.2 KiB
Rust
92 lines
3.2 KiB
Rust
// Abstract semantic graph (ASG) intermediate representation (IR)
|
|
//
|
|
// Copyright (C) 2014-2023 Ryan Specialty, LLC.
|
|
//
|
|
// This file is part of TAME.
|
|
//
|
|
// This program is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// This program is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with this program. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
//! Abstract semantic graph.
|
|
//!
|
|
//! The [abstract semantic graph][asg] (ASG) is an IR representing the
|
|
//! relationship between objects using a directed [graph][].
|
|
//! An _object_ is an identifier or expression.
|
|
//!
|
|
//! Since TAME is a declarative language,
|
|
//! the ASG does not represent control flow;
|
|
//! instead, it represents the relationship between objects and their
|
|
//! dependencies.
|
|
//! Control flow is determined solely by the [linker][crate::ld] based on
|
|
//! these dependencies.
|
|
//!
|
|
//! See [`crate::global`] for available index sizes depending on context.
|
|
//! For example,
|
|
//! a linker may choose to use [`crate::global::ProgIdentSize`];
|
|
//!
|
|
//!
|
|
//! Graph Ontology
|
|
//! ==============
|
|
//! Each node (vertex) in the graph represents an [`Object`],
|
|
//! such as an identifier or an expression.
|
|
//! For information on how [`Object`]s are stored and represented on the
|
|
//! graph,
|
|
//! and for information on relationships between objects,
|
|
//! see the [`graph::object`] module.
|
|
//!
|
|
//! A visualization of the graph ontology is provided here:
|
|
//!
|
|
//! 
|
|
//!
|
|
//! Graphs may contain cycles for recursive functions—that is,
|
|
//! TAME's ASG is _not_ a DAG.
|
|
//! Mutually recursive functions are therefore represented as
|
|
//! [strongly connected components][scc].
|
|
//!
|
|
//! [asg]: https://en.wikipedia.org/wiki/Abstract_semantic_graph
|
|
//! [graph]: https://en.wikipedia.org/wiki/Graph_(discrete_mathematics)
|
|
//! [scc]: https://en.wikipedia.org/wiki/Strongly_connected_component
|
|
//!
|
|
//! Missing Identifiers
|
|
//! -------------------
|
|
//! Since identifiers in TAME can be defined in any order relative to their
|
|
//! dependencies within a source file,
|
|
//! it is often the case that a dependency will have to be added to the
|
|
//! graph before it is resolved.
|
|
//! For example,
|
|
//! [`Asg::add_dep_lookup`] will add an [`Ident::Missing`] to the graph
|
|
//! if either identifier has not yet been declared.
|
|
|
|
mod error;
|
|
mod graph;
|
|
|
|
pub mod air;
|
|
|
|
pub use error::AsgError;
|
|
pub use graph::{
|
|
object::{
|
|
expr::{Expr, ExprDim, ExprOp},
|
|
ident::{
|
|
FragmentText, Ident, IdentKind, Source, TransitionError,
|
|
TransitionResult, UnresolvedError,
|
|
},
|
|
Object, ObjectIndex, ObjectKind,
|
|
},
|
|
visit,
|
|
xmli::AsgTreeToXirf,
|
|
Asg, AsgResult, IndexType,
|
|
};
|
|
|
|
/// Default concrete ASG implementation.
|
|
pub type DefaultAsg = graph::Asg;
|