1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394
// Copyright (c) 2017 Fabian Schuiki //! This module implements the scoreboard building blocks. Scoreboards are the //! driving mechanism behind moore. They keep track of the results of each //! compilation step for every node in the graph. Each node can be accessed in a //! type safe manner by its ID. use std; use std::collections::{HashMap, BTreeMap}; use std::hash::Hash; use std::fmt::Debug; use id::NodeId; /// A context which provides a language-agnostic scoreboard. This is used by /// the language-specific scoreboards to communicate with the global scoreboard. pub trait GenericContext { } /// The `NodeStorage` trait allows for references to nodes to be stored and /// retrieved via a unique node ID. /// /// Once a node is created for example in an arena, a reference to it can be /// stored in a `NodeStorage` to associate it with an ID. If that ID is /// presented to the `NodeStorage` again, that same reference will be produced. /// Implementors of this trait are expected to implement it multiple times, once /// for each different ID/node type pair that they support. This then allows for /// nodes to be looked up in a type safe manner based on their ID. /// /// The `NodeStorage` does not assume ownership over the nodes added to it. /// Therefore all nodes are references of at least the lifetime `'tn`. /// /// # Example /// /// ``` /// use moore_common::score::NodeStorage; /// use std::collections::HashMap; /// /// #[derive(PartialEq, Eq, Debug)] /// struct Foo; /// #[derive(PartialEq, Eq, Debug)] /// struct Bar; /// /// #[derive(Clone, Copy, Hash, PartialEq, Eq, Debug)] /// struct FooId(usize); /// #[derive(Clone, Copy, Hash, PartialEq, Eq, Debug)] /// struct BarId(usize); /// /// struct Table<'tn> { /// foos: HashMap<FooId, &'tn Foo>, /// bars: HashMap<BarId, &'tn Bar>, /// } /// /// impl<'tn> NodeStorage<FooId> for Table<'tn> { /// type Node = &'tn Foo; /// fn get(&self, id: &FooId) -> Option<&&'tn Foo> { self.foos.get(id) } /// fn set(&mut self, id: FooId, node: &'tn Foo) -> Option<&'tn Foo> { self.foos.insert(id, node) } /// } /// /// impl<'tn> NodeStorage<BarId> for Table<'tn> { /// type Node = &'tn Bar; /// fn get(&self, id: &BarId) -> Option<&&'tn Bar> { self.bars.get(id) } /// fn set(&mut self, id: BarId, node: &'tn Bar) -> Option<&'tn Bar> { self.bars.insert(id, node) } /// } /// /// // Store node refs in table: /// let foo = Foo; /// let bar = Bar; /// let mut tbl = Table{ foos: HashMap::new(), bars: HashMap::new() }; /// tbl.set(FooId(1), &foo); /// tbl.set(BarId(2), &bar); /// /// // Retrieve node refs again: /// assert_eq!(tbl.get(&FooId(1)), Some(&&foo)); /// assert_eq!(tbl.get(&BarId(2)), Some(&&bar)); /// assert_eq!(tbl.get(&BarId(1)), None); /// assert_eq!(tbl.get(&FooId(2)), None); /// /// // The following would produce a compiler error due to type mismatch: /// // let _: &Foo = *tbl.get(&BarId(1)).unwrap(); /// // let _: &Bar = *tbl.get(&FooId(2)).unwrap(); /// ``` pub trait NodeStorage<I> { /// The type of the node that is returned when presented with an ID of type /// `I`. type Node; /// Obtains a reference to the node with the given ID. /// /// Returns `None` when no node with the given ID exists. fn get(&self, id: &I) -> Option<&Self::Node>; /// Store a reference to a node under the given ID. /// /// Later that reference can be retrieved again by presenting the same ID to /// the `get` function. Returns the previously stored entry, if any. fn set(&mut self, id: I, node: Self::Node) -> Option<Self::Node>; } // Implement the NodeStorage trait for HashMaps. impl<K,V> NodeStorage<K> for HashMap<K,V> where K: Hash + Eq { type Node = V; fn get(&self, id: &K) -> Option<&V> { HashMap::get(self, id) } fn set(&mut self, id: K, node: V) -> Option<V> { HashMap::insert(self, id, node) } } // Implement the NodeStorage trait for BTreeMaps. impl<K,V> NodeStorage<K> for BTreeMap<K,V> where K: Ord { type Node = V; fn get(&self, id: &K) -> Option<&V> { BTreeMap::get(self, id) } fn set(&mut self, id: K, node: V) -> Option<V> { BTreeMap::insert(self, id, node) } } /// The `NodeMaker` trait allows for nodes to be generated from an ID. /// /// This is useful in conjunction with the `NodeStorage` and `Scoreboard` /// traits. If a value is requested that the scoreboard cannot find, this trait /// allows for the node to be generated. For example, if the AST for a node is /// requested but does not exist, this trait can be implemented in such a way /// that said AST is loaded. This allows for complex on-demand loading and /// compilation to be implemented. /// /// The nodes are expected to be owned either by the caller or some arena. /// Therefore only a reference to the created node is returned. /// /// # Example /// /// ``` /// use moore_common::score::{self, NodeMaker}; /// /// #[derive(PartialEq, Eq, Debug)] /// struct Foo; /// #[derive(PartialEq, Eq, Debug)] /// struct Bar; /// /// struct FooId(usize); /// struct BarId(usize); /// /// struct Table; /// /// impl<'tn> NodeMaker<FooId, &'tn Foo> for Table { /// fn make(&self, id: FooId) -> score::Result<&'tn Foo> { /// Ok(unsafe { &*(1 as *const Foo) }) // usually you would allocate this in an arena /// } /// } /// /// impl<'tn> NodeMaker<BarId, &'tn Bar> for Table { /// fn make(&self, id: BarId) -> score::Result<&'tn Bar> { /// Ok(unsafe { &*(1 as *const Bar) }) // usually you would allocate this in an arena /// } /// } /// /// let tbl = Table; /// let foo = tbl.make(FooId(1)).unwrap(); /// let bar = tbl.make(BarId(2)).unwrap(); /// assert_eq!(foo, &Foo); /// assert_eq!(bar, &Bar); /// /// // The following would produce a compiler error due to type mismatch: /// // assert_eq!(foo, &Bar); /// // assert_eq!(bar, &Foo); /// ``` pub trait NodeMaker<I, N> { /// Creates the node with the given ID. /// /// Returns `Err(())` upon failure. Note that the generated node has /// lifetime `'tn` that outlives the `NodeMaker`. This is required to allow /// for the `NodeMaker` to generate multiple nodes at the same time. The /// generated nodes should be owned by an arena or the owner of the /// `NodeMaker` itself. fn make(&self, id: I) -> Result<N>; } /// The result of making a node. Errors that occur while making a node should be /// reported via a separate channel, e.g. diagnostics, which provide more /// information to the user. pub type Result<T> = std::result::Result<T, ()>; /// A reference to a node. /// /// Newtypes around `NodeId` should implement this trait to offer functionality /// common to all node references. pub trait NodeRef: Copy + Eq + Ord + Hash + Debug + Into<NodeId> { /// Allocate a new reference. /// /// Creates a new unique reference. Calls `NodeId::alloc()` under the hood. fn alloc() -> Self { Self::new(NodeId::alloc()) } /// Create a new reference from an existing node ID. fn new(id: NodeId) -> Self; } /// Create a new node reference. /// /// This is merely a wrapper around `NodeId` to provide a type safe /// representation of a node. /// /// # Example /// /// ``` /// #[macro_use] /// extern crate moore_common; /// # extern crate rustc_serialize; /// /// # fn main() { /// node_ref!(FooRef); /// node_ref!(BarRef); /// # } /// ``` /// /// This creates two structs `FooRef` and `BarRef` that both wrap around a /// `NodeId`. #[macro_export] macro_rules! node_ref { ($name:ident) => { #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, RustcEncodable, RustcDecodable, Hash)] pub struct $name($crate::NodeId); impl std::fmt::Debug for $name { fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result { write!(f, "{}({})", stringify!($name), self.0) } } impl Into<$crate::NodeId> for $name { fn into(self) -> $crate::NodeId { self.0 } } impl $crate::score::NodeRef for $name { fn new(id: $crate::NodeId) -> $name { $name(id) } } } } /// Create a new group of node references. /// /// This is a simple enum that contains variants for each of the references. /// Implements `From` for the various references, and `Into<NodeId>`. #[macro_export] macro_rules! node_ref_group { ($name:ident: $($var:ident($ty:ty),)+) => { #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, RustcEncodable, RustcDecodable, Hash)] pub enum $name { $($var($ty),)* } impl std::fmt::Debug for $name { fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result { node_ref_group!(MATCHES *self, $($name::$var(id) => write!(f, "{}({:?})", stringify!($var), id)),*) } } impl Into<$crate::NodeId> for $name { fn into(self) -> $crate::NodeId { node_ref_group!(MATCHES self, $($name::$var(id) => id.into()),*) } } $( impl From<$ty> for $name { fn from(id: $ty) -> $name { $name::$var(id) } } )* }; (MATCHES $value:expr, $($lhs:pat => $rhs:expr),+) => { match $value { $($lhs => $rhs),+ } }; } /// Create a new table that implements the `NodeStorage` trait. /// /// The resulting table can then be used to store nodes in a type safe manner. /// /// # Example /// /// ``` /// #[macro_use] /// extern crate moore_common; /// use moore_common::score::NodeStorage; /// # extern crate rustc_serialize; /// # use std::collections::HashMap; /// /// #[derive(PartialEq, Eq, Hash, Debug)] /// struct FooRef(usize); /// #[derive(PartialEq, Eq, Hash, Debug)] /// struct BarRef(usize); /// /// #[derive(PartialEq, Eq, Debug)] /// struct Foo; /// #[derive(PartialEq, Eq, Debug)] /// struct Bar; /// /// node_storage!(NodeTable<'tn>: /// foos: FooRef => &'tn Foo, /// bars: BarRef => &'tn Bar, /// ); /// /// # fn main() { /// let foo = &Foo; /// let bar = &Bar; /// /// let mut tbl = NodeTable::new(); /// tbl.set(FooRef(0), foo); /// tbl.set(BarRef(1), bar); /// /// assert_eq!(tbl.get(&FooRef(0)), Some(&foo)); /// assert_eq!(tbl.get(&BarRef(1)), Some(&bar)); /// /// // The following would produce a compiler error due to the type mismatch: /// // assert_eq!(tbl.get(&BarRef(0)), Some(&foo)); /// // assert_eq!(tbl.get(&FooRef(1)), Some(&bar)); /// # } /// ``` #[macro_export] macro_rules! node_storage { ($name:ident<$($lt:tt),+>: $($node_name:ident : $node_ref:ty => $node:ty,)+) => { pub struct $name<$($lt),*> { $($node_name: std::collections::HashMap<$node_ref, $node>,)* } node_storage!(STRUCT_IMPL $name; $($lt),*; $($node_name, $node_ref, $node;)*); }; ($name:ident<$($lt:tt),+> where ($($wh:tt)+): $($node_name:ident : $node_ref:ty => $node:ty,)+) => { pub struct $name<$($lt),*> where $($wh)* { $($node_name: std::collections::HashMap<$node_ref, $node>,)* } node_storage!(STRUCT_IMPL $name; $($lt),*; $($node_name, $node_ref, $node;)*); }; (STRUCT_IMPL $name:ident; $($lt:tt),+; $($node_name:ident, $node_ref:ty, $node:ty;)*) => { impl<$($lt),*> $name<$($lt),*> { /// Create a new empty table. pub fn new() -> $name<$($lt),*> { $name { $($node_name: std::collections::HashMap::new(),)* } } } node_storage!(TRAIT_IMPL $name; $($lt),*; $($node_name, $node_ref, $node;)*); }; (TRAIT_IMPL $name:ident; $($lt:tt),+; $node_name:ident, $node_ref:ty, $node:ty; $($tail_name:ident, $tail_ref:ty, $tail:ty;)*) => { impl<$($lt),*> $crate::score::NodeStorage<$node_ref> for $name<$($lt),*> { type Node = $node; fn get(&self, id: &$node_ref) -> Option<&$node> { self.$node_name.get(id) } fn set(&mut self, id: $node_ref, node: $node) -> Option<$node> { self.$node_name.insert(id, node) } } node_storage!(TRAIT_IMPL $name; $($lt),*; $($tail_name, $tail_ref, $tail;)*); }; (TRAIT_IMPL $name:ident; $($lt:tt),*;) => {} }