// Copyright 2012-2014 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. #![allow(non_camel_case_types)] use back::svh::Svh; use driver::session::Session; use metadata::csearch; use mc = middle::mem_categorization; use middle::const_eval; use middle::dependency_format; use middle::lang_items::{ExchangeHeapLangItem, OpaqueStructLangItem}; use middle::lang_items::{TyDescStructLangItem, TyVisitorTraitLangItem}; use middle::freevars; use middle::resolve; use middle::resolve_lifetime; use middle::ty; use middle::subst::Subst; use middle::typeck; use middle::typeck::MethodCall; use middle::ty_fold; use middle::ty_fold::TypeFolder; use middle; use util::ppaux::{note_and_explain_region, bound_region_ptr_to_str}; use util::ppaux::{trait_store_to_str, ty_to_str}; use util::ppaux::{Repr, UserString}; use util::common::{indenter}; use util::nodemap::{NodeMap, NodeSet, DefIdMap, DefIdSet, FnvHashMap}; use std::cast; use std::cell::{Cell, RefCell}; use std::cmp; use std::fmt::Show; use std::fmt; use std::hash::{Hash, sip}; use std::iter::AdditiveIterator; use std::ops; use std::rc::Rc; use collections::{HashMap, HashSet}; use syntax::abi; use syntax::ast::*; use syntax::ast_util::{is_local, lit_is_str}; use syntax::ast_util; use syntax::attr; use syntax::attr::AttrMetaMethods; use syntax::codemap::Span; use syntax::parse::token; use syntax::parse::token::InternedString; use syntax::{ast, ast_map}; use syntax::owned_slice::OwnedSlice; use syntax::util::small_vector::SmallVector; use collections::enum_set::{EnumSet, CLike}; pub type Disr = u64; pub static INITIAL_DISCRIMINANT_VALUE: Disr = 0; // Data types #[deriving(Eq, TotalEq, Hash)] pub struct field { pub ident: ast::Ident, pub mt: mt } #[deriving(Clone)] pub enum MethodContainer { TraitContainer(ast::DefId), ImplContainer(ast::DefId), } #[deriving(Clone)] pub struct Method { pub ident: ast::Ident, pub generics: ty::Generics, pub fty: BareFnTy, pub explicit_self: ast::ExplicitSelf_, pub vis: ast::Visibility, pub def_id: ast::DefId, pub container: MethodContainer, // If this method is provided, we need to know where it came from pub provided_source: Option } impl Method { pub fn new(ident: ast::Ident, generics: ty::Generics, fty: BareFnTy, explicit_self: ast::ExplicitSelf_, vis: ast::Visibility, def_id: ast::DefId, container: MethodContainer, provided_source: Option) -> Method { Method { ident: ident, generics: generics, fty: fty, explicit_self: explicit_self, vis: vis, def_id: def_id, container: container, provided_source: provided_source } } pub fn container_id(&self) -> ast::DefId { match self.container { TraitContainer(id) => id, ImplContainer(id) => id, } } } #[deriving(Clone, Eq, TotalEq, Hash)] pub struct mt { pub ty: t, pub mutbl: ast::Mutability, } #[deriving(Clone, Eq, TotalEq, Hash, Encodable, Decodable, Show)] pub enum TraitStore { /// Box UniqTraitStore, /// &Trait and &mut Trait RegionTraitStore(Region, ast::Mutability), } #[deriving(Clone)] pub struct field_ty { pub name: Name, pub id: DefId, pub vis: ast::Visibility, pub origin: ast::DefId, // The DefId of the struct in which the field is declared. } // Contains information needed to resolve types and (in the future) look up // the types of AST nodes. #[deriving(Eq, TotalEq, Hash)] pub struct creader_cache_key { pub cnum: CrateNum, pub pos: uint, pub len: uint } pub type creader_cache = RefCell>; pub struct intern_key { sty: *sty, } // NB: Do not replace this with #[deriving(Eq)]. The automatically-derived // implementation will not recurse through sty and you will get stack // exhaustion. impl cmp::Eq for intern_key { fn eq(&self, other: &intern_key) -> bool { unsafe { *self.sty == *other.sty } } fn ne(&self, other: &intern_key) -> bool { !self.eq(other) } } impl TotalEq for intern_key {} impl Hash for intern_key { fn hash(&self, s: &mut W) { unsafe { (*self.sty).hash(s) } } } pub enum ast_ty_to_ty_cache_entry { atttce_unresolved, /* not resolved yet */ atttce_resolved(t) /* resolved to a type, irrespective of region */ } #[deriving(Clone, Eq, Decodable, Encodable)] pub struct ItemVariances { pub self_param: Option, pub type_params: OwnedSlice, pub region_params: OwnedSlice } #[deriving(Clone, Eq, Decodable, Encodable, Show)] pub enum Variance { Covariant, // T <: T iff A <: B -- e.g., function return type Invariant, // T <: T iff B == A -- e.g., type of mutable cell Contravariant, // T <: T iff B <: A -- e.g., function param type Bivariant, // T <: T -- e.g., unused type parameter } #[deriving(Clone)] pub enum AutoAdjustment { AutoAddEnv(ty::TraitStore), AutoDerefRef(AutoDerefRef), AutoObject(ty::TraitStore, ty::BuiltinBounds, ast::DefId, /* Trait ID */ ty::substs /* Trait substitutions */) } #[deriving(Clone, Decodable, Encodable)] pub struct AutoDerefRef { pub autoderefs: uint, pub autoref: Option } #[deriving(Clone, Decodable, Encodable, Eq, Show)] pub enum AutoRef { /// Convert from T to &T AutoPtr(Region, ast::Mutability), /// Convert from ~[]/&[] to &[] (or str) AutoBorrowVec(Region, ast::Mutability), /// Convert from ~[]/&[] to &&[] (or str) AutoBorrowVecRef(Region, ast::Mutability), /// Convert from T to *T AutoUnsafe(ast::Mutability), /// Convert from Box/&Trait to &Trait AutoBorrowObj(Region, ast::Mutability), } /// The data structure to keep track of all the information that typechecker /// generates so that so that it can be reused and doesn't have to be redone /// later on. pub struct ctxt { // Specifically use a speedy hash algorithm for this hash map, it's used // quite often. pub interner: RefCell>>, pub next_id: Cell, pub sess: Session, pub def_map: resolve::DefMap, pub named_region_map: resolve_lifetime::NamedRegionMap, pub region_maps: middle::region::RegionMaps, // Stores the types for various nodes in the AST. Note that this table // is not guaranteed to be populated until after typeck. See // typeck::check::fn_ctxt for details. pub node_types: node_type_table, // Stores the type parameters which were substituted to obtain the type // of this node. This only applies to nodes that refer to entities // parameterized by type parameters, such as generic fns, types, or // other items. pub node_type_substs: RefCell>>, // Maps from a method to the method "descriptor" pub methods: RefCell>>, // Maps from a trait def-id to a list of the def-ids of its methods pub trait_method_def_ids: RefCell>>>, // A cache for the trait_methods() routine pub trait_methods_cache: RefCell>>>>, pub impl_trait_cache: RefCell>>>, pub trait_refs: RefCell>>, pub trait_defs: RefCell>>, pub map: ast_map::Map, pub intrinsic_defs: RefCell>, pub freevars: RefCell, pub tcache: type_cache, pub rcache: creader_cache, pub short_names_cache: RefCell>, pub needs_unwind_cleanup_cache: RefCell>, pub tc_cache: RefCell>, pub ast_ty_to_ty_cache: RefCell>, pub enum_var_cache: RefCell>>>>, pub ty_param_defs: RefCell>, pub adjustments: RefCell>, pub normalized_cache: RefCell>, pub lang_items: middle::lang_items::LanguageItems, // A mapping of fake provided method def_ids to the default implementation pub provided_method_sources: RefCell>, pub supertraits: RefCell>>>>, pub superstructs: RefCell>>, pub struct_fields: RefCell>>>, // Maps from def-id of a type or region parameter to its // (inferred) variance. pub item_variance_map: RefCell>>, // A mapping from the def ID of an enum or struct type to the def ID // of the method that implements its destructor. If the type is not // present in this map, it does not have a destructor. This map is // populated during the coherence phase of typechecking. pub destructor_for_type: RefCell>, // A method will be in this list if and only if it is a destructor. pub destructors: RefCell, // Maps a trait onto a list of impls of that trait. pub trait_impls: RefCell>>>>, // Maps a DefId of a type to a list of its inherent impls. // Contains implementations of methods that are inherent to a type. // Methods in these implementations don't need to be exported. pub inherent_impls: RefCell>>>>, // Maps a DefId of an impl to a list of its methods. // Note that this contains all of the impls that we know about, // including ones in other crates. It's not clear that this is the best // way to do it. pub impl_methods: RefCell>>, // Set of used unsafe nodes (functions or blocks). Unsafe nodes not // present in this set can be warned about. pub used_unsafe: RefCell, // Set of nodes which mark locals as mutable which end up getting used at // some point. Local variable definitions not in this set can be warned // about. pub used_mut_nodes: RefCell, // vtable resolution information for impl declarations pub impl_vtables: typeck::impl_vtable_map, // The set of external nominal types whose implementations have been read. // This is used for lazy resolution of methods. pub populated_external_types: RefCell, // The set of external traits whose implementations have been read. This // is used for lazy resolution of traits. pub populated_external_traits: RefCell, // Borrows pub upvar_borrow_map: RefCell, // These two caches are used by const_eval when decoding external statics // and variants that are found. pub extern_const_statics: RefCell>>, pub extern_const_variants: RefCell>>, pub method_map: typeck::MethodMap, pub vtable_map: typeck::vtable_map, pub dependency_formats: RefCell, } pub enum tbox_flag { has_params = 1, has_self = 2, needs_infer = 4, has_regions = 8, has_ty_err = 16, has_ty_bot = 32, // a meta-pub flag: subst may be required if the type has parameters, a self // type, or references bound regions needs_subst = 1 | 2 | 8 } pub type t_box = &'static t_box_; pub struct t_box_ { pub sty: sty, pub id: uint, pub flags: uint, } // To reduce refcounting cost, we're representing types as unsafe pointers // throughout the compiler. These are simply casted t_box values. Use ty::get // to cast them back to a box. (Without the cast, compiler performance suffers // ~15%.) This does mean that a t value relies on the ctxt to keep its box // alive, and using ty::get is unsafe when the ctxt is no longer alive. enum t_opaque {} #[allow(raw_pointer_deriving)] #[deriving(Clone, Eq, TotalEq, Hash)] pub struct t { inner: *t_opaque } impl fmt::Show for t { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { f.buf.write_str("*t_opaque") } } pub fn get(t: t) -> t_box { unsafe { let t2: t_box = cast::transmute(t); t2 } } pub fn tbox_has_flag(tb: t_box, flag: tbox_flag) -> bool { (tb.flags & (flag as uint)) != 0u } pub fn type_has_params(t: t) -> bool { tbox_has_flag(get(t), has_params) } pub fn type_has_self(t: t) -> bool { tbox_has_flag(get(t), has_self) } pub fn type_needs_infer(t: t) -> bool { tbox_has_flag(get(t), needs_infer) } pub fn type_id(t: t) -> uint { get(t).id } #[deriving(Clone, Eq, TotalEq, Hash)] pub struct BareFnTy { pub fn_style: ast::FnStyle, pub abi: abi::Abi, pub sig: FnSig, } #[deriving(Clone, Eq, TotalEq, Hash)] pub struct ClosureTy { pub fn_style: ast::FnStyle, pub onceness: ast::Onceness, pub store: TraitStore, pub bounds: BuiltinBounds, pub sig: FnSig, } /** * Signature of a function type, which I have arbitrarily * decided to use to refer to the input/output types. * * - `binder_id` is the node id where this fn type appeared; * it is used to identify all the bound regions appearing * in the input/output types that are bound by this fn type * (vs some enclosing or enclosed fn type) * - `inputs` is the list of arguments and their modes. * - `output` is the return type. * - `variadic` indicates whether this is a varidic function. (only true for foreign fns) */ #[deriving(Clone, Eq, TotalEq, Hash)] pub struct FnSig { pub binder_id: ast::NodeId, pub inputs: Vec, pub output: t, pub variadic: bool } #[deriving(Clone, Eq, TotalEq, Hash)] pub struct param_ty { pub idx: uint, pub def_id: DefId } /// Representation of regions: #[deriving(Clone, Eq, TotalEq, Hash, Encodable, Decodable, Show)] pub enum Region { // Region bound in a type or fn declaration which will be // substituted 'early' -- that is, at the same time when type // parameters are substituted. ReEarlyBound(/* param id */ ast::NodeId, /*index*/ uint, ast::Name), // Region bound in a function scope, which will be substituted when the // function is called. The first argument must be the `binder_id` of // some enclosing function signature. ReLateBound(/* binder_id */ ast::NodeId, BoundRegion), /// When checking a function body, the types of all arguments and so forth /// that refer to bound region parameters are modified to refer to free /// region parameters. ReFree(FreeRegion), /// A concrete region naming some expression within the current function. ReScope(NodeId), /// Static data that has an "infinite" lifetime. Top in the region lattice. ReStatic, /// A region variable. Should not exist after typeck. ReInfer(InferRegion), /// Empty lifetime is for data that is never accessed. /// Bottom in the region lattice. We treat ReEmpty somewhat /// specially; at least right now, we do not generate instances of /// it during the GLB computations, but rather /// generate an error instead. This is to improve error messages. /// The only way to get an instance of ReEmpty is to have a region /// variable with no constraints. ReEmpty, } /** * Upvars do not get their own node-id. Instead, we use the pair of * the original var id (that is, the root variable that is referenced * by the upvar) and the id of the closure expression. */ #[deriving(Clone, Eq, TotalEq, Hash)] pub struct UpvarId { pub var_id: ast::NodeId, pub closure_expr_id: ast::NodeId, } #[deriving(Clone, Eq, TotalEq, Hash, Show)] pub enum BorrowKind { /// Data must be immutable and is aliasable. ImmBorrow, /// Data must be immutable but not aliasable. This kind of borrow /// cannot currently be expressed by the user and is used only in /// implicit closure bindings. It is needed when you the closure /// is borrowing or mutating a mutable referent, e.g.: /// /// let x: &mut int = ...; /// let y = || *x += 5; /// /// If we were to try to translate this closure into a more explicit /// form, we'd encounter an error with the code as written: /// /// struct Env { x: & &mut int } /// let x: &mut int = ...; /// let y = (&mut Env { &x }, fn_ptr); // Closure is pair of env and fn /// fn fn_ptr(env: &mut Env) { **env.x += 5; } /// /// This is then illegal because you cannot mutate a `&mut` found /// in an aliasable location. To solve, you'd have to translate with /// an `&mut` borrow: /// /// struct Env { x: & &mut int } /// let x: &mut int = ...; /// let y = (&mut Env { &mut x }, fn_ptr); // changed from &x to &mut x /// fn fn_ptr(env: &mut Env) { **env.x += 5; } /// /// Now the assignment to `**env.x` is legal, but creating a /// mutable pointer to `x` is not because `x` is not mutable. We /// could fix this by declaring `x` as `let mut x`. This is ok in /// user code, if awkward, but extra weird for closures, since the /// borrow is hidden. /// /// So we introduce a "unique imm" borrow -- the referent is /// immutable, but not aliasable. This solves the problem. For /// simplicity, we don't give users the way to express this /// borrow, it's just used when translating closures. UniqueImmBorrow, /// Data is mutable and not aliasable. MutBorrow } /** * Information describing the borrowing of an upvar. This is computed * during `typeck`, specifically by `regionck`. The general idea is * that the compiler analyses treat closures like: * * let closure: &'e fn() = || { * x = 1; // upvar x is assigned to * use(y); // upvar y is read * foo(&z); // upvar z is borrowed immutably * }; * * as if they were "desugared" to something loosely like: * * struct Vars<'x,'y,'z> { x: &'x mut int, * y: &'y const int, * z: &'z int } * let closure: &'e fn() = { * fn f(env: &Vars) { * *env.x = 1; * use(*env.y); * foo(env.z); * } * let env: &'e mut Vars<'x,'y,'z> = &mut Vars { x: &'x mut x, * y: &'y const y, * z: &'z z }; * (env, f) * }; * * This is basically what happens at runtime. The closure is basically * an existentially quantified version of the `(env, f)` pair. * * This data structure indicates the region and mutability of a single * one of the `x...z` borrows. * * It may not be obvious why each borrowed variable gets its own * lifetime (in the desugared version of the example, these are indicated * by the lifetime parameters `'x`, `'y`, and `'z` in the `Vars` definition). * Each such lifetime must encompass the lifetime `'e` of the closure itself, * but need not be identical to it. The reason that this makes sense: * * - Callers are only permitted to invoke the closure, and hence to * use the pointers, within the lifetime `'e`, so clearly `'e` must * be a sublifetime of `'x...'z`. * - The closure creator knows which upvars were borrowed by the closure * and thus `x...z` will be reserved for `'x...'z` respectively. * - Through mutation, the borrowed upvars can actually escape * the closure, so sometimes it is necessary for them to be larger * than the closure lifetime itself. */ #[deriving(Eq, Clone)] pub struct UpvarBorrow { pub kind: BorrowKind, pub region: ty::Region, } pub type UpvarBorrowMap = HashMap; impl Region { pub fn is_bound(&self) -> bool { match self { &ty::ReEarlyBound(..) => true, &ty::ReLateBound(..) => true, _ => false } } } #[deriving(Clone, Eq, Ord, TotalEq, TotalOrd, Hash, Encodable, Decodable, Show)] pub struct FreeRegion { pub scope_id: NodeId, pub bound_region: BoundRegion } #[deriving(Clone, Eq, Ord, TotalEq, TotalOrd, Hash, Encodable, Decodable, Show)] pub enum BoundRegion { /// An anonymous region parameter for a given fn (&T) BrAnon(uint), /// Named region parameters for functions (a in &'a T) /// /// The def-id is needed to distinguish free regions in /// the event of shadowing. BrNamed(ast::DefId, ast::Name), /// Fresh bound identifiers created during GLB computations. BrFresh(uint), } /** * Represents the values to use when substituting lifetime parameters. * If the value is `ErasedRegions`, then this subst is occurring during * trans, and all region parameters will be replaced with `ty::ReStatic`. */ #[deriving(Clone, Eq, TotalEq, Hash)] pub enum RegionSubsts { ErasedRegions, NonerasedRegions(OwnedSlice) } /** * The type substs represents the kinds of things that can be substituted to * convert a polytype into a monotype. Note however that substituting bound * regions other than `self` is done through a different mechanism: * * - `tps` represents the type parameters in scope. They are indexed * according to the order in which they were declared. * * - `self_r` indicates the region parameter `self` that is present on nominal * types (enums, structs) declared as having a region parameter. `self_r` * should always be none for types that are not region-parameterized and * Some(_) for types that are. The only bound region parameter that should * appear within a region-parameterized type is `self`. * * - `self_ty` is the type to which `self` should be remapped, if any. The * `self` type is rather funny in that it can only appear on traits and is * always substituted away to the implementing type for a trait. */ #[deriving(Clone, Eq, TotalEq, Hash)] pub struct substs { pub self_ty: Option, pub tps: Vec, pub regions: RegionSubsts, } mod primitives { use super::t_box_; use syntax::ast; macro_rules! def_prim_ty( ($name:ident, $sty:expr, $id:expr) => ( pub static $name: t_box_ = t_box_ { sty: $sty, id: $id, flags: 0, }; ) ) def_prim_ty!(TY_NIL, super::ty_nil, 0) def_prim_ty!(TY_BOOL, super::ty_bool, 1) def_prim_ty!(TY_CHAR, super::ty_char, 2) def_prim_ty!(TY_INT, super::ty_int(ast::TyI), 3) def_prim_ty!(TY_I8, super::ty_int(ast::TyI8), 4) def_prim_ty!(TY_I16, super::ty_int(ast::TyI16), 5) def_prim_ty!(TY_I32, super::ty_int(ast::TyI32), 6) def_prim_ty!(TY_I64, super::ty_int(ast::TyI64), 7) def_prim_ty!(TY_UINT, super::ty_uint(ast::TyU), 8) def_prim_ty!(TY_U8, super::ty_uint(ast::TyU8), 9) def_prim_ty!(TY_U16, super::ty_uint(ast::TyU16), 10) def_prim_ty!(TY_U32, super::ty_uint(ast::TyU32), 11) def_prim_ty!(TY_U64, super::ty_uint(ast::TyU64), 12) def_prim_ty!(TY_F32, super::ty_float(ast::TyF32), 14) def_prim_ty!(TY_F64, super::ty_float(ast::TyF64), 15) def_prim_ty!(TY_F128, super::ty_float(ast::TyF128), 16) pub static TY_BOT: t_box_ = t_box_ { sty: super::ty_bot, id: 16, flags: super::has_ty_bot as uint, }; pub static TY_ERR: t_box_ = t_box_ { sty: super::ty_err, id: 17, flags: super::has_ty_err as uint, }; pub static LAST_PRIMITIVE_ID: uint = 18; } // NB: If you change this, you'll probably want to change the corresponding // AST structure in libsyntax/ast.rs as well. #[deriving(Clone, Eq, TotalEq, Hash)] pub enum sty { ty_nil, ty_bot, ty_bool, ty_char, ty_int(ast::IntTy), ty_uint(ast::UintTy), ty_float(ast::FloatTy), ty_enum(DefId, substs), ty_box(t), ty_uniq(t), ty_str, ty_vec(mt, Option), // Second field is length. ty_ptr(mt), ty_rptr(Region, mt), ty_bare_fn(BareFnTy), ty_closure(Box), ty_trait(Box), ty_struct(DefId, substs), ty_tup(Vec), ty_param(param_ty), // type parameter ty_self(DefId), /* special, implicit `self` type parameter; * def_id is the id of the trait */ ty_infer(InferTy), // something used only during inference/typeck ty_err, // Also only used during inference/typeck, to represent // the type of an erroneous expression (helps cut down // on non-useful type error messages) } #[deriving(Clone, Eq, TotalEq, Hash)] pub struct TyTrait { pub def_id: DefId, pub substs: substs, pub store: TraitStore, pub bounds: BuiltinBounds } #[deriving(Eq, TotalEq, Hash)] pub struct TraitRef { pub def_id: DefId, pub substs: substs } #[deriving(Clone, Eq)] pub enum IntVarValue { IntType(ast::IntTy), UintType(ast::UintTy), } #[deriving(Clone, Show)] pub enum terr_vstore_kind { terr_vec, terr_str, terr_fn, terr_trait } #[deriving(Clone, Show)] pub struct expected_found { pub expected: T, pub found: T } // Data structures used in type unification #[deriving(Clone, Show)] pub enum type_err { terr_mismatch, terr_fn_style_mismatch(expected_found), terr_onceness_mismatch(expected_found), terr_abi_mismatch(expected_found), terr_mutability, terr_sigil_mismatch(expected_found), terr_box_mutability, terr_ptr_mutability, terr_ref_mutability, terr_vec_mutability, terr_tuple_size(expected_found), terr_ty_param_size(expected_found), terr_record_size(expected_found), terr_record_mutability, terr_record_fields(expected_found), terr_arg_count, terr_regions_does_not_outlive(Region, Region), terr_regions_not_same(Region, Region), terr_regions_no_overlap(Region, Region), terr_regions_insufficiently_polymorphic(BoundRegion, Region), terr_regions_overly_polymorphic(BoundRegion, Region), terr_trait_stores_differ(terr_vstore_kind, expected_found), terr_sorts(expected_found), terr_integer_as_char, terr_int_mismatch(expected_found), terr_float_mismatch(expected_found), terr_traits(expected_found), terr_builtin_bounds(expected_found), terr_variadic_mismatch(expected_found) } #[deriving(Eq, TotalEq, Hash)] pub struct ParamBounds { pub builtin_bounds: BuiltinBounds, pub trait_bounds: Vec> } pub type BuiltinBounds = EnumSet; #[deriving(Clone, Encodable, Eq, TotalEq, Decodable, Hash, Show)] #[repr(uint)] pub enum BuiltinBound { BoundStatic, BoundSend, BoundSized, BoundCopy, BoundShare, } pub fn EmptyBuiltinBounds() -> BuiltinBounds { EnumSet::empty() } pub fn AllBuiltinBounds() -> BuiltinBounds { let mut set = EnumSet::empty(); set.add(BoundStatic); set.add(BoundSend); set.add(BoundSized); set.add(BoundShare); set } impl CLike for BuiltinBound { fn to_uint(&self) -> uint { *self as uint } fn from_uint(v: uint) -> BuiltinBound { unsafe { cast::transmute(v) } } } #[deriving(Clone, Eq, TotalEq, Hash)] pub struct TyVid(pub uint); #[deriving(Clone, Eq, TotalEq, Hash)] pub struct IntVid(pub uint); #[deriving(Clone, Eq, TotalEq, Hash)] pub struct FloatVid(pub uint); #[deriving(Clone, Eq, TotalEq, Encodable, Decodable, Hash)] pub struct RegionVid { pub id: uint } #[deriving(Clone, Eq, TotalEq, Hash)] pub enum InferTy { TyVar(TyVid), IntVar(IntVid), FloatVar(FloatVid) } #[deriving(Clone, Encodable, Decodable, TotalEq, Hash, Show)] pub enum InferRegion { ReVar(RegionVid), ReSkolemized(uint, BoundRegion) } impl cmp::Eq for InferRegion { fn eq(&self, other: &InferRegion) -> bool { match ((*self), *other) { (ReVar(rva), ReVar(rvb)) => { rva == rvb } (ReSkolemized(rva, _), ReSkolemized(rvb, _)) => { rva == rvb } _ => false } } fn ne(&self, other: &InferRegion) -> bool { !((*self) == (*other)) } } pub trait Vid { fn to_uint(&self) -> uint; } impl Vid for TyVid { fn to_uint(&self) -> uint { let TyVid(v) = *self; v } } impl fmt::Show for TyVid { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result{ write!(f.buf, "", self.to_uint()) } } impl Vid for IntVid { fn to_uint(&self) -> uint { let IntVid(v) = *self; v } } impl fmt::Show for IntVid { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f.buf, "", self.to_uint()) } } impl Vid for FloatVid { fn to_uint(&self) -> uint { let FloatVid(v) = *self; v } } impl fmt::Show for FloatVid { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f.buf, "", self.to_uint()) } } impl Vid for RegionVid { fn to_uint(&self) -> uint { self.id } } impl fmt::Show for RegionVid { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { self.id.fmt(f) } } impl fmt::Show for FnSig { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { // grr, without tcx not much we can do. write!(f.buf, "(...)") } } impl fmt::Show for InferTy { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match *self { TyVar(ref v) => v.fmt(f), IntVar(ref v) => v.fmt(f), FloatVar(ref v) => v.fmt(f), } } } impl fmt::Show for IntVarValue { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { match *self { IntType(ref v) => v.fmt(f), UintType(ref v) => v.fmt(f), } } } #[deriving(Clone)] pub struct TypeParameterDef { pub ident: ast::Ident, pub def_id: ast::DefId, pub bounds: Rc, pub default: Option } #[deriving(Encodable, Decodable, Clone)] pub struct RegionParameterDef { pub name: ast::Name, pub def_id: ast::DefId, } /// Information about the type/lifetime parameters associated with an item. /// Analogous to ast::Generics. #[deriving(Clone)] pub struct Generics { /// List of type parameters declared on the item. pub type_param_defs: Rc>, /// List of region parameters declared on the item. /// For a fn or method, only includes *early-bound* lifetimes. pub region_param_defs: Rc>, } impl Generics { pub fn has_type_params(&self) -> bool { !self.type_param_defs.is_empty() } pub fn type_param_defs<'a>(&'a self) -> &'a [TypeParameterDef] { self.type_param_defs.as_slice() } pub fn region_param_defs<'a>(&'a self) -> &'a [RegionParameterDef] { self.region_param_defs.as_slice() } } /// When type checking, we use the `ParameterEnvironment` to track /// details about the type/lifetime parameters that are in scope. /// It primarily stores the bounds information. /// /// Note: This information might seem to be redundant with the data in /// `tcx.ty_param_defs`, but it is not. That table contains the /// parameter definitions from an "outside" perspective, but this /// struct will contain the bounds for a parameter as seen from inside /// the function body. Currently the only real distinction is that /// bound lifetime parameters are replaced with free ones, but in the /// future I hope to refine the representation of types so as to make /// more distinctions clearer. pub struct ParameterEnvironment { /// A substitution that can be applied to move from /// the "outer" view of a type or method to the "inner" view. /// In general, this means converting from bound parameters to /// free parameters. Since we currently represent bound/free type /// parameters in the same way, this only has an affect on regions. pub free_substs: ty::substs, /// Bound on the Self parameter pub self_param_bound: Option>, /// Bounds on each numbered type parameter pub type_param_bounds: Vec , } /// A polytype. /// /// - `bounds`: The list of bounds for each type parameter. The length of the /// list also tells you how many type parameters there are. /// /// - `rp`: true if the type is region-parameterized. Types can have at /// most one region parameter, always called `&self`. /// /// - `ty`: the base type. May have reference to the (unsubstituted) bound /// region `&self` or to (unsubstituted) ty_param types #[deriving(Clone)] pub struct ty_param_bounds_and_ty { pub generics: Generics, pub ty: t } /// As `ty_param_bounds_and_ty` but for a trait ref. pub struct TraitDef { pub generics: Generics, pub bounds: BuiltinBounds, pub trait_ref: Rc, } pub struct ty_param_substs_and_ty { pub substs: ty::substs, pub ty: ty::t } pub type type_cache = RefCell>; pub type node_type_table = RefCell>; pub fn mk_ctxt(s: Session, dm: resolve::DefMap, named_region_map: resolve_lifetime::NamedRegionMap, map: ast_map::Map, freevars: freevars::freevar_map, region_maps: middle::region::RegionMaps, lang_items: middle::lang_items::LanguageItems) -> ctxt { ctxt { named_region_map: named_region_map, item_variance_map: RefCell::new(DefIdMap::new()), interner: RefCell::new(FnvHashMap::new()), next_id: Cell::new(primitives::LAST_PRIMITIVE_ID), sess: s, def_map: dm, region_maps: region_maps, node_types: RefCell::new(HashMap::new()), node_type_substs: RefCell::new(NodeMap::new()), trait_refs: RefCell::new(NodeMap::new()), trait_defs: RefCell::new(DefIdMap::new()), map: map, intrinsic_defs: RefCell::new(DefIdMap::new()), freevars: RefCell::new(freevars), tcache: RefCell::new(DefIdMap::new()), rcache: RefCell::new(HashMap::new()), short_names_cache: RefCell::new(HashMap::new()), needs_unwind_cleanup_cache: RefCell::new(HashMap::new()), tc_cache: RefCell::new(HashMap::new()), ast_ty_to_ty_cache: RefCell::new(NodeMap::new()), enum_var_cache: RefCell::new(DefIdMap::new()), methods: RefCell::new(DefIdMap::new()), trait_method_def_ids: RefCell::new(DefIdMap::new()), trait_methods_cache: RefCell::new(DefIdMap::new()), impl_trait_cache: RefCell::new(DefIdMap::new()), ty_param_defs: RefCell::new(NodeMap::new()), adjustments: RefCell::new(NodeMap::new()), normalized_cache: RefCell::new(HashMap::new()), lang_items: lang_items, provided_method_sources: RefCell::new(DefIdMap::new()), supertraits: RefCell::new(DefIdMap::new()), superstructs: RefCell::new(DefIdMap::new()), struct_fields: RefCell::new(DefIdMap::new()), destructor_for_type: RefCell::new(DefIdMap::new()), destructors: RefCell::new(DefIdSet::new()), trait_impls: RefCell::new(DefIdMap::new()), inherent_impls: RefCell::new(DefIdMap::new()), impl_methods: RefCell::new(DefIdMap::new()), used_unsafe: RefCell::new(NodeSet::new()), used_mut_nodes: RefCell::new(NodeSet::new()), impl_vtables: RefCell::new(DefIdMap::new()), populated_external_types: RefCell::new(DefIdSet::new()), populated_external_traits: RefCell::new(DefIdSet::new()), upvar_borrow_map: RefCell::new(HashMap::new()), extern_const_statics: RefCell::new(DefIdMap::new()), extern_const_variants: RefCell::new(DefIdMap::new()), method_map: RefCell::new(FnvHashMap::new()), vtable_map: RefCell::new(FnvHashMap::new()), dependency_formats: RefCell::new(HashMap::new()), } } // Type constructors // Interns a type/name combination, stores the resulting box in cx.interner, // and returns the box as cast to an unsafe ptr (see comments for t above). pub fn mk_t(cx: &ctxt, st: sty) -> t { // Check for primitive types. match st { ty_nil => return mk_nil(), ty_err => return mk_err(), ty_bool => return mk_bool(), ty_int(i) => return mk_mach_int(i), ty_uint(u) => return mk_mach_uint(u), ty_float(f) => return mk_mach_float(f), ty_char => return mk_char(), ty_bot => return mk_bot(), _ => {} }; let key = intern_key { sty: &st }; match cx.interner.borrow().find(&key) { Some(t) => unsafe { return cast::transmute(&t.sty); }, _ => () } let mut flags = 0u; fn rflags(r: Region) -> uint { (has_regions as uint) | { match r { ty::ReInfer(_) => needs_infer as uint, _ => 0u } } } fn sflags(substs: &substs) -> uint { let mut f = 0u; for tt in substs.tps.iter() { f |= get(*tt).flags; } match substs.regions { ErasedRegions => {} NonerasedRegions(ref regions) => { for r in regions.iter() { f |= rflags(*r) } } } return f; } match &st { &ty_nil | &ty_bool | &ty_char | &ty_int(_) | &ty_float(_) | &ty_uint(_) | &ty_str => {} // You might think that we could just return ty_err for // any type containing ty_err as a component, and get // rid of the has_ty_err flag -- likewise for ty_bot (with // the exception of function types that return bot). // But doing so caused sporadic memory corruption, and // neither I (tjc) nor nmatsakis could figure out why, // so we're doing it this way. &ty_bot => flags |= has_ty_bot as uint, &ty_err => flags |= has_ty_err as uint, &ty_param(_) => flags |= has_params as uint, &ty_infer(_) => flags |= needs_infer as uint, &ty_self(_) => flags |= has_self as uint, &ty_enum(_, ref substs) | &ty_struct(_, ref substs) => { flags |= sflags(substs); } &ty_trait(box ty::TyTrait { ref substs, store, .. }) => { flags |= sflags(substs); match store { RegionTraitStore(r, _) => { flags |= rflags(r); } _ => {} } } &ty_box(tt) | &ty_uniq(tt) => { flags |= get(tt).flags } &ty_ptr(ref m) | &ty_vec(ref m, _) => { flags |= get(m.ty).flags; } &ty_rptr(r, ref m) => { flags |= rflags(r); flags |= get(m.ty).flags; } &ty_tup(ref ts) => for tt in ts.iter() { flags |= get(*tt).flags; }, &ty_bare_fn(ref f) => { for a in f.sig.inputs.iter() { flags |= get(*a).flags; } flags |= get(f.sig.output).flags; // T -> _|_ is *not* _|_ ! flags &= !(has_ty_bot as uint); } &ty_closure(ref f) => { match f.store { RegionTraitStore(r, _) => { flags |= rflags(r); } _ => {} } for a in f.sig.inputs.iter() { flags |= get(*a).flags; } flags |= get(f.sig.output).flags; // T -> _|_ is *not* _|_ ! flags &= !(has_ty_bot as uint); } } let t = box t_box_ { sty: st, id: cx.next_id.get(), flags: flags, }; let sty_ptr = &t.sty as *sty; let key = intern_key { sty: sty_ptr, }; cx.interner.borrow_mut().insert(key, t); cx.next_id.set(cx.next_id.get() + 1); unsafe { cast::transmute::<*sty, t>(sty_ptr) } } #[inline] pub fn mk_prim_t(primitive: &'static t_box_) -> t { unsafe { cast::transmute::<&'static t_box_, t>(primitive) } } #[inline] pub fn mk_nil() -> t { mk_prim_t(&primitives::TY_NIL) } #[inline] pub fn mk_err() -> t { mk_prim_t(&primitives::TY_ERR) } #[inline] pub fn mk_bot() -> t { mk_prim_t(&primitives::TY_BOT) } #[inline] pub fn mk_bool() -> t { mk_prim_t(&primitives::TY_BOOL) } #[inline] pub fn mk_int() -> t { mk_prim_t(&primitives::TY_INT) } #[inline] pub fn mk_i8() -> t { mk_prim_t(&primitives::TY_I8) } #[inline] pub fn mk_i16() -> t { mk_prim_t(&primitives::TY_I16) } #[inline] pub fn mk_i32() -> t { mk_prim_t(&primitives::TY_I32) } #[inline] pub fn mk_i64() -> t { mk_prim_t(&primitives::TY_I64) } #[inline] pub fn mk_f32() -> t { mk_prim_t(&primitives::TY_F32) } #[inline] pub fn mk_f64() -> t { mk_prim_t(&primitives::TY_F64) } #[inline] pub fn mk_f128() -> t { mk_prim_t(&primitives::TY_F128) } #[inline] pub fn mk_uint() -> t { mk_prim_t(&primitives::TY_UINT) } #[inline] pub fn mk_u8() -> t { mk_prim_t(&primitives::TY_U8) } #[inline] pub fn mk_u16() -> t { mk_prim_t(&primitives::TY_U16) } #[inline] pub fn mk_u32() -> t { mk_prim_t(&primitives::TY_U32) } #[inline] pub fn mk_u64() -> t { mk_prim_t(&primitives::TY_U64) } pub fn mk_mach_int(tm: ast::IntTy) -> t { match tm { ast::TyI => mk_int(), ast::TyI8 => mk_i8(), ast::TyI16 => mk_i16(), ast::TyI32 => mk_i32(), ast::TyI64 => mk_i64(), } } pub fn mk_mach_uint(tm: ast::UintTy) -> t { match tm { ast::TyU => mk_uint(), ast::TyU8 => mk_u8(), ast::TyU16 => mk_u16(), ast::TyU32 => mk_u32(), ast::TyU64 => mk_u64(), } } pub fn mk_mach_float(tm: ast::FloatTy) -> t { match tm { ast::TyF32 => mk_f32(), ast::TyF64 => mk_f64(), ast::TyF128 => mk_f128() } } #[inline] pub fn mk_char() -> t { mk_prim_t(&primitives::TY_CHAR) } pub fn mk_str(cx: &ctxt) -> t { mk_t(cx, ty_str) } pub fn mk_str_slice(cx: &ctxt, r: Region, m: ast::Mutability) -> t { mk_rptr(cx, r, mt { ty: mk_t(cx, ty_str), mutbl: m }) } pub fn mk_enum(cx: &ctxt, did: ast::DefId, substs: substs) -> t { // take a copy of substs so that we own the vectors inside mk_t(cx, ty_enum(did, substs)) } pub fn mk_box(cx: &ctxt, ty: t) -> t { mk_t(cx, ty_box(ty)) } pub fn mk_uniq(cx: &ctxt, ty: t) -> t { mk_t(cx, ty_uniq(ty)) } pub fn mk_ptr(cx: &ctxt, tm: mt) -> t { mk_t(cx, ty_ptr(tm)) } pub fn mk_rptr(cx: &ctxt, r: Region, tm: mt) -> t { mk_t(cx, ty_rptr(r, tm)) } pub fn mk_mut_rptr(cx: &ctxt, r: Region, ty: t) -> t { mk_rptr(cx, r, mt {ty: ty, mutbl: ast::MutMutable}) } pub fn mk_imm_rptr(cx: &ctxt, r: Region, ty: t) -> t { mk_rptr(cx, r, mt {ty: ty, mutbl: ast::MutImmutable}) } pub fn mk_mut_ptr(cx: &ctxt, ty: t) -> t { mk_ptr(cx, mt {ty: ty, mutbl: ast::MutMutable}) } pub fn mk_imm_ptr(cx: &ctxt, ty: t) -> t { mk_ptr(cx, mt {ty: ty, mutbl: ast::MutImmutable}) } pub fn mk_nil_ptr(cx: &ctxt) -> t { mk_ptr(cx, mt {ty: mk_nil(), mutbl: ast::MutImmutable}) } pub fn mk_vec(cx: &ctxt, tm: mt, sz: Option) -> t { mk_t(cx, ty_vec(tm, sz)) } pub fn mk_slice(cx: &ctxt, r: Region, tm: mt) -> t { mk_rptr(cx, r, mt { ty: mk_vec(cx, tm, None), mutbl: tm.mutbl }) } pub fn mk_tup(cx: &ctxt, ts: Vec) -> t { mk_t(cx, ty_tup(ts)) } pub fn mk_closure(cx: &ctxt, fty: ClosureTy) -> t { mk_t(cx, ty_closure(box fty)) } pub fn mk_bare_fn(cx: &ctxt, fty: BareFnTy) -> t { mk_t(cx, ty_bare_fn(fty)) } pub fn mk_ctor_fn(cx: &ctxt, binder_id: ast::NodeId, input_tys: &[ty::t], output: ty::t) -> t { let input_args = input_tys.iter().map(|t| *t).collect(); mk_bare_fn(cx, BareFnTy { fn_style: ast::NormalFn, abi: abi::Rust, sig: FnSig { binder_id: binder_id, inputs: input_args, output: output, variadic: false } }) } pub fn mk_trait(cx: &ctxt, did: ast::DefId, substs: substs, store: TraitStore, bounds: BuiltinBounds) -> t { // take a copy of substs so that we own the vectors inside let inner = box TyTrait { def_id: did, substs: substs, store: store, bounds: bounds }; mk_t(cx, ty_trait(inner)) } pub fn mk_struct(cx: &ctxt, struct_id: ast::DefId, substs: substs) -> t { // take a copy of substs so that we own the vectors inside mk_t(cx, ty_struct(struct_id, substs)) } pub fn mk_var(cx: &ctxt, v: TyVid) -> t { mk_infer(cx, TyVar(v)) } pub fn mk_int_var(cx: &ctxt, v: IntVid) -> t { mk_infer(cx, IntVar(v)) } pub fn mk_float_var(cx: &ctxt, v: FloatVid) -> t { mk_infer(cx, FloatVar(v)) } pub fn mk_infer(cx: &ctxt, it: InferTy) -> t { mk_t(cx, ty_infer(it)) } pub fn mk_self(cx: &ctxt, did: ast::DefId) -> t { mk_t(cx, ty_self(did)) } pub fn mk_param(cx: &ctxt, n: uint, k: DefId) -> t { mk_t(cx, ty_param(param_ty { idx: n, def_id: k })) } pub fn walk_ty(ty: t, f: |t|) { maybe_walk_ty(ty, |t| { f(t); true }); } pub fn maybe_walk_ty(ty: t, f: |t| -> bool) { if !f(ty) { return; } match get(ty).sty { ty_nil | ty_bot | ty_bool | ty_char | ty_int(_) | ty_uint(_) | ty_float(_) | ty_str | ty_self(_) | ty_infer(_) | ty_param(_) | ty_err => {} ty_box(ty) | ty_uniq(ty) => maybe_walk_ty(ty, f), ty_ptr(ref tm) | ty_rptr(_, ref tm) | ty_vec(ref tm, _) => { maybe_walk_ty(tm.ty, f); } ty_enum(_, ref substs) | ty_struct(_, ref substs) | ty_trait(box TyTrait { ref substs, .. }) => { for subty in (*substs).tps.iter() { maybe_walk_ty(*subty, |x| f(x)); } } ty_tup(ref ts) => { for tt in ts.iter() { maybe_walk_ty(*tt, |x| f(x)); } } ty_bare_fn(ref ft) => { for a in ft.sig.inputs.iter() { maybe_walk_ty(*a, |x| f(x)); } maybe_walk_ty(ft.sig.output, f); } ty_closure(ref ft) => { for a in ft.sig.inputs.iter() { maybe_walk_ty(*a, |x| f(x)); } maybe_walk_ty(ft.sig.output, f); } } } // Folds types from the bottom up. pub fn fold_ty(cx: &ctxt, t0: t, fldop: |t| -> t) -> t { let mut f = ty_fold::BottomUpFolder {tcx: cx, fldop: fldop}; f.fold_ty(t0) } pub fn walk_regions_and_ty(cx: &ctxt, ty: t, fldr: |r: Region|, fldt: |t: t|) -> t { ty_fold::RegionFolder::general(cx, |r| { fldr(r); r }, |t| { fldt(t); t }).fold_ty(ty) } // Substitute *only* type parameters. Used in trans where regions are erased. pub fn subst_tps(tcx: &ctxt, tps: &[t], self_ty_opt: Option, typ: t) -> t { let mut subst = TpsSubst { tcx: tcx, self_ty_opt: self_ty_opt, tps: tps }; return subst.fold_ty(typ); struct TpsSubst<'a> { tcx: &'a ctxt, self_ty_opt: Option, tps: &'a [t], } impl<'a> TypeFolder for TpsSubst<'a> { fn tcx<'a>(&'a self) -> &'a ctxt { self.tcx } fn fold_ty(&mut self, t: ty::t) -> ty::t { if self.tps.len() == 0u && self.self_ty_opt.is_none() { return t; } let tb = ty::get(t); if self.self_ty_opt.is_none() && !tbox_has_flag(tb, has_params) { return t; } match ty::get(t).sty { ty_param(p) => { self.tps[p.idx] } ty_self(_) => { match self.self_ty_opt { None => self.tcx.sess.bug("ty_self unexpected here"), Some(self_ty) => self_ty } } _ => { ty_fold::super_fold_ty(self, t) } } } } } pub fn substs_is_noop(substs: &substs) -> bool { let regions_is_noop = match substs.regions { ErasedRegions => false, // may be used to canonicalize NonerasedRegions(ref regions) => regions.is_empty() }; substs.tps.len() == 0u && regions_is_noop && substs.self_ty.is_none() } pub fn substs_to_str(cx: &ctxt, substs: &substs) -> ~str { substs.repr(cx) } pub fn subst(cx: &ctxt, substs: &substs, typ: t) -> t { typ.subst(cx, substs) } // Type utilities pub fn type_is_nil(ty: t) -> bool { get(ty).sty == ty_nil } pub fn type_is_bot(ty: t) -> bool { (get(ty).flags & (has_ty_bot as uint)) != 0 } pub fn type_is_error(ty: t) -> bool { (get(ty).flags & (has_ty_err as uint)) != 0 } pub fn type_needs_subst(ty: t) -> bool { tbox_has_flag(get(ty), needs_subst) } pub fn trait_ref_contains_error(tref: &ty::TraitRef) -> bool { tref.substs.self_ty.iter().any(|&t| type_is_error(t)) || tref.substs.tps.iter().any(|&t| type_is_error(t)) } pub fn type_is_ty_var(ty: t) -> bool { match get(ty).sty { ty_infer(TyVar(_)) => true, _ => false } } pub fn type_is_bool(ty: t) -> bool { get(ty).sty == ty_bool } pub fn type_is_self(ty: t) -> bool { match get(ty).sty { ty_self(..) => true, _ => false } } fn type_is_slice(ty:t) -> bool { match get(ty).sty { ty_rptr(_, mt) => match get(mt.ty).sty { ty_vec(_, None) | ty_str => true, _ => false, }, _ => false } } pub fn type_is_structural(ty: t) -> bool { match get(ty).sty { ty_struct(..) | ty_tup(_) | ty_enum(..) | ty_closure(_) | ty_trait(..) | ty_vec(_, Some(_)) => true, _ => type_is_slice(ty) } } pub fn type_is_simd(cx: &ctxt, ty: t) -> bool { match get(ty).sty { ty_struct(did, _) => lookup_simd(cx, did), _ => false } } pub fn sequence_element_type(cx: &ctxt, ty: t) -> t { match get(ty).sty { ty_vec(mt, Some(_)) => mt.ty, ty_ptr(mt{ty: t, ..}) | ty_rptr(_, mt{ty: t, ..}) | ty_box(t) | ty_uniq(t) => match get(t).sty { ty_vec(mt, None) => mt.ty, ty_str => mk_mach_uint(ast::TyU8), _ => cx.sess.bug("sequence_element_type called on non-sequence value"), }, _ => cx.sess.bug("sequence_element_type called on non-sequence value"), } } pub fn simd_type(cx: &ctxt, ty: t) -> t { match get(ty).sty { ty_struct(did, ref substs) => { let fields = lookup_struct_fields(cx, did); lookup_field_type(cx, did, fields.get(0).id, substs) } _ => fail!("simd_type called on invalid type") } } pub fn simd_size(cx: &ctxt, ty: t) -> uint { match get(ty).sty { ty_struct(did, _) => { let fields = lookup_struct_fields(cx, did); fields.len() } _ => fail!("simd_size called on invalid type") } } pub fn type_is_boxed(ty: t) -> bool { match get(ty).sty { ty_box(_) => true, _ => false } } pub fn type_is_region_ptr(ty: t) -> bool { match get(ty).sty { ty_rptr(_, mt) => match get(mt.ty).sty { // FIXME(nrc, DST) slices weren't regarded as rptrs, so we preserve this // odd behaviour for now. (But ~[] were unique. I have no idea why). ty_vec(_, None) | ty_str => false, _ => true }, _ => false } } pub fn type_is_unsafe_ptr(ty: t) -> bool { match get(ty).sty { ty_ptr(_) => return true, _ => return false } } pub fn type_is_unique(ty: t) -> bool { match get(ty).sty { ty_uniq(_) => true, _ => false } } /* A scalar type is one that denotes an atomic datum, with no sub-components. (A ty_ptr is scalar because it represents a non-managed pointer, so its contents are abstract to rustc.) */ pub fn type_is_scalar(ty: t) -> bool { match get(ty).sty { ty_nil | ty_bool | ty_char | ty_int(_) | ty_float(_) | ty_uint(_) | ty_infer(IntVar(_)) | ty_infer(FloatVar(_)) | ty_bare_fn(..) | ty_ptr(_) => true, _ => false } } pub fn type_needs_drop(cx: &ctxt, ty: t) -> bool { type_contents(cx, ty).needs_drop(cx) } // Some things don't need cleanups during unwinding because the // task can free them all at once later. Currently only things // that only contain scalars and shared boxes can avoid unwind // cleanups. pub fn type_needs_unwind_cleanup(cx: &ctxt, ty: t) -> bool { match cx.needs_unwind_cleanup_cache.borrow().find(&ty) { Some(&result) => return result, None => () } let mut tycache = HashSet::new(); let needs_unwind_cleanup = type_needs_unwind_cleanup_(cx, ty, &mut tycache, false); cx.needs_unwind_cleanup_cache.borrow_mut().insert(ty, needs_unwind_cleanup); return needs_unwind_cleanup; } fn type_needs_unwind_cleanup_(cx: &ctxt, ty: t, tycache: &mut HashSet, encountered_box: bool) -> bool { // Prevent infinite recursion if !tycache.insert(ty) { return false; } let mut encountered_box = encountered_box; let mut needs_unwind_cleanup = false; maybe_walk_ty(ty, |ty| { let old_encountered_box = encountered_box; let result = match get(ty).sty { ty_box(_) => { encountered_box = true; true } ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) | ty_tup(_) | ty_ptr(_) => { true } ty_enum(did, ref substs) => { for v in (*enum_variants(cx, did)).iter() { for aty in v.args.iter() { let t = subst(cx, substs, *aty); needs_unwind_cleanup |= type_needs_unwind_cleanup_(cx, t, tycache, encountered_box); } } !needs_unwind_cleanup } ty_uniq(_) => { // Once we're inside a box, the annihilator will find // it and destroy it. if !encountered_box { needs_unwind_cleanup = true; false } else { true } } _ => { needs_unwind_cleanup = true; false } }; encountered_box = old_encountered_box; result }); return needs_unwind_cleanup; } /** * Type contents is how the type checker reasons about kinds. * They track what kinds of things are found within a type. You can * think of them as kind of an "anti-kind". They track the kinds of values * and thinks that are contained in types. Having a larger contents for * a type tends to rule that type *out* from various kinds. For example, * a type that contains a reference is not sendable. * * The reason we compute type contents and not kinds is that it is * easier for me (nmatsakis) to think about what is contained within * a type than to think about what is *not* contained within a type. */ pub struct TypeContents { pub bits: u64 } macro_rules! def_type_content_sets( (mod $mname:ident { $($name:ident = $bits:expr),+ }) => { mod $mname { use middle::ty::TypeContents; $(pub static $name: TypeContents = TypeContents { bits: $bits };)+ } } ) def_type_content_sets!( mod TC { None = 0b0000_0000__0000_0000__0000, // Things that are interior to the value (first nibble): InteriorUnsized = 0b0000_0000__0000_0000__0001, InteriorUnsafe = 0b0000_0000__0000_0000__0010, // InteriorAll = 0b00000000__00000000__1111, // Things that are owned by the value (second and third nibbles): OwnsOwned = 0b0000_0000__0000_0001__0000, OwnsDtor = 0b0000_0000__0000_0010__0000, OwnsManaged /* see [1] below */ = 0b0000_0000__0000_0100__0000, OwnsAffine = 0b0000_0000__0000_1000__0000, OwnsAll = 0b0000_0000__1111_1111__0000, // Things that are reachable by the value in any way (fourth nibble): ReachesNonsendAnnot = 0b0000_0001__0000_0000__0000, ReachesBorrowed = 0b0000_0010__0000_0000__0000, // ReachesManaged /* see [1] below */ = 0b0000_0100__0000_0000__0000, ReachesMutable = 0b0000_1000__0000_0000__0000, ReachesNoShare = 0b0001_0000__0000_0000__0000, ReachesAll = 0b0001_1111__0000_0000__0000, // Things that cause values to *move* rather than *copy* Moves = 0b0000_0000__0000_1011__0000, // Things that mean drop glue is necessary NeedsDrop = 0b0000_0000__0000_0111__0000, // Things that prevent values from being sent // // Note: For checking whether something is sendable, it'd // be sufficient to have ReachesManaged. However, we include // both ReachesManaged and OwnsManaged so that when // a parameter has a bound T:Send, we are able to deduce // that it neither reaches nor owns a managed pointer. Nonsendable = 0b0000_0111__0000_0100__0000, // Things that prevent values from being considered 'static Nonstatic = 0b0000_0010__0000_0000__0000, // Things that prevent values from being considered sized Nonsized = 0b0000_0000__0000_0000__0001, // Things that prevent values from being shared Nonsharable = 0b0001_0000__0000_0000__0000, // Things that make values considered not POD (would be same // as `Moves`, but for the fact that managed data `@` is // not considered POD) Noncopy = 0b0000_0000__0000_1111__0000, // Bits to set when a managed value is encountered // // [1] Do not set the bits TC::OwnsManaged or // TC::ReachesManaged directly, instead reference // TC::Managed to set them both at once. Managed = 0b0000_0100__0000_0100__0000, // All bits All = 0b1111_1111__1111_1111__1111 } ) impl TypeContents { pub fn meets_bound(&self, cx: &ctxt, bb: BuiltinBound) -> bool { match bb { BoundStatic => self.is_static(cx), BoundSend => self.is_sendable(cx), BoundSized => self.is_sized(cx), BoundCopy => self.is_copy(cx), BoundShare => self.is_sharable(cx), } } pub fn when(&self, cond: bool) -> TypeContents { if cond {*self} else {TC::None} } pub fn intersects(&self, tc: TypeContents) -> bool { (self.bits & tc.bits) != 0 } pub fn is_static(&self, _: &ctxt) -> bool { !self.intersects(TC::Nonstatic) } pub fn is_sendable(&self, _: &ctxt) -> bool { !self.intersects(TC::Nonsendable) } pub fn is_sharable(&self, _: &ctxt) -> bool { !self.intersects(TC::Nonsharable) } pub fn owns_managed(&self) -> bool { self.intersects(TC::OwnsManaged) } pub fn owns_owned(&self) -> bool { self.intersects(TC::OwnsOwned) } pub fn is_sized(&self, _: &ctxt) -> bool { !self.intersects(TC::Nonsized) } pub fn is_copy(&self, _: &ctxt) -> bool { !self.intersects(TC::Noncopy) } pub fn interior_unsafe(&self) -> bool { self.intersects(TC::InteriorUnsafe) } pub fn interior_unsized(&self) -> bool { self.intersects(TC::InteriorUnsized) } pub fn moves_by_default(&self, _: &ctxt) -> bool { self.intersects(TC::Moves) } pub fn needs_drop(&self, _: &ctxt) -> bool { self.intersects(TC::NeedsDrop) } pub fn owned_pointer(&self) -> TypeContents { /*! * Includes only those bits that still apply * when indirected through a `Box` pointer */ TC::OwnsOwned | ( *self & (TC::OwnsAll | TC::ReachesAll)) } pub fn reference(&self, bits: TypeContents) -> TypeContents { /*! * Includes only those bits that still apply * when indirected through a reference (`&`) */ bits | ( *self & TC::ReachesAll) } pub fn managed_pointer(&self) -> TypeContents { /*! * Includes only those bits that still apply * when indirected through a managed pointer (`@`) */ TC::Managed | ( *self & TC::ReachesAll) } pub fn unsafe_pointer(&self) -> TypeContents { /*! * Includes only those bits that still apply * when indirected through an unsafe pointer (`*`) */ *self & TC::ReachesAll } pub fn union(v: &[T], f: |&T| -> TypeContents) -> TypeContents { v.iter().fold(TC::None, |tc, t| tc | f(t)) } pub fn has_dtor(&self) -> bool { self.intersects(TC::OwnsDtor) } } impl ops::BitOr for TypeContents { fn bitor(&self, other: &TypeContents) -> TypeContents { TypeContents {bits: self.bits | other.bits} } } impl ops::BitAnd for TypeContents { fn bitand(&self, other: &TypeContents) -> TypeContents { TypeContents {bits: self.bits & other.bits} } } impl ops::Sub for TypeContents { fn sub(&self, other: &TypeContents) -> TypeContents { TypeContents {bits: self.bits & !other.bits} } } impl fmt::Show for TypeContents { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { write!(f.buf, "TypeContents({:t})", self.bits) } } pub fn type_is_static(cx: &ctxt, t: ty::t) -> bool { type_contents(cx, t).is_static(cx) } pub fn type_is_sendable(cx: &ctxt, t: ty::t) -> bool { type_contents(cx, t).is_sendable(cx) } pub fn type_interior_is_unsafe(cx: &ctxt, t: ty::t) -> bool { type_contents(cx, t).interior_unsafe() } pub fn type_contents(cx: &ctxt, ty: t) -> TypeContents { let ty_id = type_id(ty); match cx.tc_cache.borrow().find(&ty_id) { Some(tc) => { return *tc; } None => {} } let mut cache = HashMap::new(); let result = tc_ty(cx, ty, &mut cache); cx.tc_cache.borrow_mut().insert(ty_id, result); return result; fn tc_ty(cx: &ctxt, ty: t, cache: &mut HashMap) -> TypeContents { // Subtle: Note that we are *not* using cx.tc_cache here but rather a // private cache for this walk. This is needed in the case of cyclic // types like: // // struct List { next: Box>, ... } // // When computing the type contents of such a type, we wind up deeply // recursing as we go. So when we encounter the recursive reference // to List, we temporarily use TC::None as its contents. Later we'll // patch up the cache with the correct value, once we've computed it // (this is basically a co-inductive process, if that helps). So in // the end we'll compute TC::OwnsOwned, in this case. // // The problem is, as we are doing the computation, we will also // compute an *intermediate* contents for, e.g., Option of // TC::None. This is ok during the computation of List itself, but if // we stored this intermediate value into cx.tc_cache, then later // requests for the contents of Option would also yield TC::None // which is incorrect. This value was computed based on the crutch // value for the type contents of list. The correct value is // TC::OwnsOwned. This manifested as issue #4821. let ty_id = type_id(ty); match cache.find(&ty_id) { Some(tc) => { return *tc; } None => {} } match cx.tc_cache.borrow().find(&ty_id) { // Must check both caches! Some(tc) => { return *tc; } None => {} } cache.insert(ty_id, TC::None); let result = match get(ty).sty { // Scalar and unique types are sendable, and durable ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) | ty_bare_fn(_) | ty::ty_char | ty_str => { TC::None } ty_closure(ref c) => { closure_contents(cx, *c) } ty_box(typ) => { tc_ty(cx, typ, cache).managed_pointer() } ty_uniq(typ) => { match get(typ).sty { ty_str => TC::OwnsOwned, _ => tc_ty(cx, typ, cache).owned_pointer(), } } ty_trait(box ty::TyTrait { store, bounds, .. }) => { object_contents(cx, store, bounds) } ty_ptr(ref mt) => { tc_ty(cx, mt.ty, cache).unsafe_pointer() } ty_rptr(r, ref mt) => { match get(mt.ty).sty { ty_str => borrowed_contents(r, ast::MutImmutable), _ => tc_ty(cx, mt.ty, cache).reference(borrowed_contents(r, mt.mutbl)), } } ty_vec(mt, _) => { tc_mt(cx, mt, cache) } ty_struct(did, ref substs) => { let flds = struct_fields(cx, did, substs); let mut res = TypeContents::union(flds.as_slice(), |f| tc_mt(cx, f.mt, cache)); if ty::has_dtor(cx, did) { res = res | TC::OwnsDtor; } apply_lang_items(cx, did, res) } ty_tup(ref tys) => { TypeContents::union(tys.as_slice(), |ty| tc_ty(cx, *ty, cache)) } ty_enum(did, ref substs) => { let variants = substd_enum_variants(cx, did, substs); let res = TypeContents::union(variants.as_slice(), |variant| { TypeContents::union(variant.args.as_slice(), |arg_ty| { tc_ty(cx, *arg_ty, cache) }) }); apply_lang_items(cx, did, res) } ty_param(p) => { // We only ever ask for the kind of types that are defined in // the current crate; therefore, the only type parameters that // could be in scope are those defined in the current crate. // If this assertion failures, it is likely because of a // failure in the cross-crate inlining code to translate a // def-id. assert_eq!(p.def_id.krate, ast::LOCAL_CRATE); let ty_param_defs = cx.ty_param_defs.borrow(); let tp_def = ty_param_defs.get(&p.def_id.node); kind_bounds_to_contents(cx, tp_def.bounds.builtin_bounds, tp_def.bounds.trait_bounds.as_slice()) } ty_self(def_id) => { // FIXME(#4678)---self should just be a ty param // Self may be bounded if the associated trait has builtin kinds // for supertraits. If so we can use those bounds. let trait_def = lookup_trait_def(cx, def_id); let traits = [trait_def.trait_ref.clone()]; kind_bounds_to_contents(cx, trait_def.bounds, traits) } ty_infer(_) => { // This occurs during coherence, but shouldn't occur at other // times. TC::All } ty_err => { cx.sess.bug("asked to compute contents of error type"); } }; cache.insert(ty_id, result); return result; } fn tc_mt(cx: &ctxt, mt: mt, cache: &mut HashMap) -> TypeContents { let mc = TC::ReachesMutable.when(mt.mutbl == MutMutable); mc | tc_ty(cx, mt.ty, cache) } fn apply_lang_items(cx: &ctxt, did: ast::DefId, tc: TypeContents) -> TypeContents { if Some(did) == cx.lang_items.no_send_bound() { tc | TC::ReachesNonsendAnnot } else if Some(did) == cx.lang_items.managed_bound() { tc | TC::Managed } else if Some(did) == cx.lang_items.no_copy_bound() { tc | TC::OwnsAffine } else if Some(did) == cx.lang_items.no_share_bound() { tc | TC::ReachesNoShare } else if Some(did) == cx.lang_items.unsafe_type() { // FIXME(#13231): This shouldn't be needed after // opt-in built-in bounds are implemented. (tc | TC::InteriorUnsafe) - TC::Nonsharable } else { tc } } fn borrowed_contents(region: ty::Region, mutbl: ast::Mutability) -> TypeContents { /*! * Type contents due to containing a reference * with the region `region` and borrow kind `bk` */ let b = match mutbl { ast::MutMutable => TC::ReachesMutable | TC::OwnsAffine, ast::MutImmutable => TC::None, }; b | (TC::ReachesBorrowed).when(region != ty::ReStatic) } fn closure_contents(cx: &ctxt, cty: &ClosureTy) -> TypeContents { // Closure contents are just like trait contents, but with potentially // even more stuff. let st = object_contents(cx, cty.store, cty.bounds); // This also prohibits "@once fn" from being copied, which allows it to // be called. Neither way really makes much sense. let ot = match cty.onceness { ast::Once => TC::OwnsAffine, ast::Many => TC::None, }; st | ot } fn object_contents(cx: &ctxt, store: TraitStore, bounds: BuiltinBounds) -> TypeContents { // These are the type contents of the (opaque) interior let contents = kind_bounds_to_contents(cx, bounds, []); match store { UniqTraitStore => { contents.owned_pointer() } RegionTraitStore(r, mutbl) => { contents.reference(borrowed_contents(r, mutbl)) } } } fn kind_bounds_to_contents(cx: &ctxt, bounds: BuiltinBounds, traits: &[Rc]) -> TypeContents { let _i = indenter(); let mut tc = TC::All; each_inherited_builtin_bound(cx, bounds, traits, |bound| { tc = tc - match bound { BoundStatic => TC::Nonstatic, BoundSend => TC::Nonsendable, BoundSized => TC::Nonsized, BoundCopy => TC::Noncopy, BoundShare => TC::Nonsharable, }; }); return tc; // Iterates over all builtin bounds on the type parameter def, including // those inherited from traits with builtin-kind-supertraits. fn each_inherited_builtin_bound(cx: &ctxt, bounds: BuiltinBounds, traits: &[Rc], f: |BuiltinBound|) { for bound in bounds.iter() { f(bound); } each_bound_trait_and_supertraits(cx, traits, |trait_ref| { let trait_def = lookup_trait_def(cx, trait_ref.def_id); for bound in trait_def.bounds.iter() { f(bound); } true }); } } } pub fn type_moves_by_default(cx: &ctxt, ty: t) -> bool { type_contents(cx, ty).moves_by_default(cx) } // True if instantiating an instance of `r_ty` requires an instance of `r_ty`. pub fn is_instantiable(cx: &ctxt, r_ty: t) -> bool { fn type_requires(cx: &ctxt, seen: &mut Vec, r_ty: t, ty: t) -> bool { debug!("type_requires({}, {})?", ::util::ppaux::ty_to_str(cx, r_ty), ::util::ppaux::ty_to_str(cx, ty)); let r = { get(r_ty).sty == get(ty).sty || subtypes_require(cx, seen, r_ty, ty) }; debug!("type_requires({}, {})? {}", ::util::ppaux::ty_to_str(cx, r_ty), ::util::ppaux::ty_to_str(cx, ty), r); return r; } fn subtypes_require(cx: &ctxt, seen: &mut Vec, r_ty: t, ty: t) -> bool { debug!("subtypes_require({}, {})?", ::util::ppaux::ty_to_str(cx, r_ty), ::util::ppaux::ty_to_str(cx, ty)); let r = match get(ty).sty { // fixed length vectors need special treatment compared to // normal vectors, since they don't necessarily have the // possibility to have length zero. ty_vec(_, Some(0)) => false, // don't need no contents ty_vec(mt, Some(_)) => type_requires(cx, seen, r_ty, mt.ty), ty_nil | ty_bot | ty_bool | ty_char | ty_int(_) | ty_uint(_) | ty_float(_) | ty_str | ty_bare_fn(_) | ty_closure(_) | ty_infer(_) | ty_err | ty_param(_) | ty_self(_) | ty_vec(_, None) => { false } ty_box(typ) | ty_uniq(typ) => { type_requires(cx, seen, r_ty, typ) } ty_rptr(_, ref mt) => { type_requires(cx, seen, r_ty, mt.ty) } ty_ptr(..) => { false // unsafe ptrs can always be NULL } ty_trait(..) => { false } ty_struct(ref did, _) if seen.contains(did) => { false } ty_struct(did, ref substs) => { seen.push(did); let fields = struct_fields(cx, did, substs); let r = fields.iter().any(|f| type_requires(cx, seen, r_ty, f.mt.ty)); seen.pop().unwrap(); r } ty_tup(ref ts) => { ts.iter().any(|t| type_requires(cx, seen, r_ty, *t)) } ty_enum(ref did, _) if seen.contains(did) => { false } ty_enum(did, ref substs) => { seen.push(did); let vs = enum_variants(cx, did); let r = !vs.is_empty() && vs.iter().all(|variant| { variant.args.iter().any(|aty| { let sty = subst(cx, substs, *aty); type_requires(cx, seen, r_ty, sty) }) }); seen.pop().unwrap(); r } }; debug!("subtypes_require({}, {})? {}", ::util::ppaux::ty_to_str(cx, r_ty), ::util::ppaux::ty_to_str(cx, ty), r); return r; } let mut seen = Vec::new(); !subtypes_require(cx, &mut seen, r_ty, r_ty) } /// Describes whether a type is representable. For types that are not /// representable, 'SelfRecursive' and 'ContainsRecursive' are used to /// distinguish between types that are recursive with themselves and types that /// contain a different recursive type. These cases can therefore be treated /// differently when reporting errors. #[deriving(Eq)] pub enum Representability { Representable, SelfRecursive, ContainsRecursive, } /// Check whether a type is representable. This means it cannot contain unboxed /// structural recursion. This check is needed for structs and enums. pub fn is_type_representable(cx: &ctxt, sp: Span, ty: t) -> Representability { // Iterate until something non-representable is found fn find_nonrepresentable>(cx: &ctxt, sp: Span, seen: &mut Vec, mut iter: It) -> Representability { for ty in iter { let r = type_structurally_recursive(cx, sp, seen, ty); if r != Representable { return r } } Representable } // Does the type `ty` directly (without indirection through a pointer) // contain any types on stack `seen`? fn type_structurally_recursive(cx: &ctxt, sp: Span, seen: &mut Vec, ty: t) -> Representability { debug!("type_structurally_recursive: {}", ::util::ppaux::ty_to_str(cx, ty)); // Compare current type to previously seen types match get(ty).sty { ty_struct(did, _) | ty_enum(did, _) => { for (i, &seen_did) in seen.iter().enumerate() { if did == seen_did { return if i == 0 { SelfRecursive } else { ContainsRecursive } } } } _ => (), } // Check inner types match get(ty).sty { // Tuples ty_tup(ref ts) => { find_nonrepresentable(cx, sp, seen, ts.iter().map(|t| *t)) } // Fixed-length vectors. // FIXME(#11924) Behavior undecided for zero-length vectors. ty_vec(mt, Some(_)) => { type_structurally_recursive(cx, sp, seen, mt.ty) } // Push struct and enum def-ids onto `seen` before recursing. ty_struct(did, ref substs) => { seen.push(did); let fields = struct_fields(cx, did, substs); let r = find_nonrepresentable(cx, sp, seen, fields.iter().map(|f| f.mt.ty)); seen.pop(); r } ty_enum(did, ref substs) => { seen.push(did); let vs = enum_variants(cx, did); let mut r = Representable; for variant in vs.iter() { let iter = variant.args.iter().map(|aty| { aty.subst_spanned(cx, substs, Some(sp)) }); r = find_nonrepresentable(cx, sp, seen, iter); if r != Representable { break } } seen.pop(); r } _ => Representable, } } debug!("is_type_representable: {}", ::util::ppaux::ty_to_str(cx, ty)); // To avoid a stack overflow when checking an enum variant or struct that // contains a different, structurally recursive type, maintain a stack // of seen types and check recursion for each of them (issues #3008, #3779). let mut seen: Vec = Vec::new(); type_structurally_recursive(cx, sp, &mut seen, ty) } pub fn type_is_trait(ty: t) -> bool { match get(ty).sty { ty_trait(..) => true, _ => false } } pub fn type_is_integral(ty: t) -> bool { match get(ty).sty { ty_infer(IntVar(_)) | ty_int(_) | ty_uint(_) => true, _ => false } } pub fn type_is_uint(ty: t) -> bool { match get(ty).sty { ty_infer(IntVar(_)) | ty_uint(ast::TyU) => true, _ => false } } pub fn type_is_char(ty: t) -> bool { match get(ty).sty { ty_char => true, _ => false } } pub fn type_is_bare_fn(ty: t) -> bool { match get(ty).sty { ty_bare_fn(..) => true, _ => false } } pub fn type_is_fp(ty: t) -> bool { match get(ty).sty { ty_infer(FloatVar(_)) | ty_float(_) => true, _ => false } } pub fn type_is_numeric(ty: t) -> bool { return type_is_integral(ty) || type_is_fp(ty); } pub fn type_is_signed(ty: t) -> bool { match get(ty).sty { ty_int(_) => true, _ => false } } pub fn type_is_machine(ty: t) -> bool { match get(ty).sty { ty_int(ast::TyI) | ty_uint(ast::TyU) => false, ty_int(..) | ty_uint(..) | ty_float(..) => true, _ => false } } // Is the type's representation size known at compile time? #[allow(dead_code)] // leaving in for DST pub fn type_is_sized(cx: &ctxt, ty: ty::t) -> bool { type_contents(cx, ty).is_sized(cx) } // Whether a type is enum like, that is an enum type with only nullary // constructors pub fn type_is_c_like_enum(cx: &ctxt, ty: t) -> bool { match get(ty).sty { ty_enum(did, _) => { let variants = enum_variants(cx, did); if variants.len() == 0 { false } else { variants.iter().all(|v| v.args.len() == 0) } } _ => false } } // Returns the type and mutability of *t. // // The parameter `explicit` indicates if this is an *explicit* dereference. // Some types---notably unsafe ptrs---can only be dereferenced explicitly. pub fn deref(t: t, explicit: bool) -> Option { match get(t).sty { ty_box(typ) | ty_uniq(typ) => match get(typ).sty { // Don't deref ~[] etc., might need to generalise this to all DST. ty_vec(_, None) | ty_str => None, _ => Some(mt { ty: typ, mutbl: ast::MutImmutable, }), }, ty_rptr(_, mt) => match get(mt.ty).sty { // Don't deref &[], might need to generalise this to all DST. ty_vec(_, None) | ty_str => None, _ => Some(mt), }, ty_ptr(mt) if explicit => Some(mt), _ => None } } // Returns the type of t[i] pub fn index(t: t) -> Option { match get(t).sty { ty_vec(mt, Some(_)) => Some(mt), ty_ptr(mt{ty: t, ..}) | ty_rptr(_, mt{ty: t, ..}) | ty_box(t) | ty_uniq(t) => match get(t).sty { ty_vec(mt, None) => Some(mt), ty_str => Some(mt {ty: mk_u8(), mutbl: ast::MutImmutable}), _ => None, }, _ => None } } pub fn node_id_to_trait_ref(cx: &ctxt, id: ast::NodeId) -> Rc { match cx.trait_refs.borrow().find(&id) { Some(t) => t.clone(), None => cx.sess.bug( format!("node_id_to_trait_ref: no trait ref for node `{}`", cx.map.node_to_str(id))) } } pub fn try_node_id_to_type(cx: &ctxt, id: ast::NodeId) -> Option { cx.node_types.borrow().find_copy(&(id as uint)) } pub fn node_id_to_type(cx: &ctxt, id: ast::NodeId) -> t { match try_node_id_to_type(cx, id) { Some(t) => t, None => cx.sess.bug( format!("node_id_to_type: no type for node `{}`", cx.map.node_to_str(id))) } } pub fn node_id_to_type_opt(cx: &ctxt, id: ast::NodeId) -> Option { match cx.node_types.borrow().find(&(id as uint)) { Some(&t) => Some(t), None => None } } // FIXME(pcwalton): Makes a copy, bleh. Probably better to not do that. pub fn node_id_to_type_params(cx: &ctxt, id: ast::NodeId) -> Vec { match cx.node_type_substs.borrow().find(&id) { None => return Vec::new(), Some(ts) => return (*ts).clone(), } } pub fn fn_is_variadic(fty: t) -> bool { match get(fty).sty { ty_bare_fn(ref f) => f.sig.variadic, ty_closure(ref f) => f.sig.variadic, ref s => { fail!("fn_is_variadic() called on non-fn type: {:?}", s) } } } pub fn ty_fn_sig(fty: t) -> FnSig { match get(fty).sty { ty_bare_fn(ref f) => f.sig.clone(), ty_closure(ref f) => f.sig.clone(), ref s => { fail!("ty_fn_sig() called on non-fn type: {:?}", s) } } } // Type accessors for substructures of types pub fn ty_fn_args(fty: t) -> Vec { match get(fty).sty { ty_bare_fn(ref f) => f.sig.inputs.clone(), ty_closure(ref f) => f.sig.inputs.clone(), ref s => { fail!("ty_fn_args() called on non-fn type: {:?}", s) } } } pub fn ty_closure_store(fty: t) -> TraitStore { match get(fty).sty { ty_closure(ref f) => f.store, ref s => { fail!("ty_closure_store() called on non-closure type: {:?}", s) } } } pub fn ty_fn_ret(fty: t) -> t { match get(fty).sty { ty_bare_fn(ref f) => f.sig.output, ty_closure(ref f) => f.sig.output, ref s => { fail!("ty_fn_ret() called on non-fn type: {:?}", s) } } } pub fn is_fn_ty(fty: t) -> bool { match get(fty).sty { ty_bare_fn(_) => true, ty_closure(_) => true, _ => false } } pub fn ty_region(tcx: &ctxt, span: Span, ty: t) -> Region { match get(ty).sty { ty_rptr(r, _) => r, ref s => { tcx.sess.span_bug( span, format!("ty_region() invoked on in appropriate ty: {:?}", s)); } } } // Returns the type of a pattern as a monotype. Like @expr_ty, this function // doesn't provide type parameter substitutions. pub fn pat_ty(cx: &ctxt, pat: &ast::Pat) -> t { return node_id_to_type(cx, pat.id); } // Returns the type of an expression as a monotype. // // NB (1): This is the PRE-ADJUSTMENT TYPE for the expression. That is, in // some cases, we insert `AutoAdjustment` annotations such as auto-deref or // auto-ref. The type returned by this function does not consider such // adjustments. See `expr_ty_adjusted()` instead. // // NB (2): This type doesn't provide type parameter substitutions; e.g. if you // ask for the type of "id" in "id(3)", it will return "fn(&int) -> int" // instead of "fn(t) -> T with T = int". If this isn't what you want, see // expr_ty_params_and_ty() below. pub fn expr_ty(cx: &ctxt, expr: &ast::Expr) -> t { return node_id_to_type(cx, expr.id); } pub fn expr_ty_opt(cx: &ctxt, expr: &ast::Expr) -> Option { return node_id_to_type_opt(cx, expr.id); } pub fn expr_ty_adjusted(cx: &ctxt, expr: &ast::Expr) -> t { /*! * * Returns the type of `expr`, considering any `AutoAdjustment` * entry recorded for that expression. * * It would almost certainly be better to store the adjusted ty in with * the `AutoAdjustment`, but I opted not to do this because it would * require serializing and deserializing the type and, although that's not * hard to do, I just hate that code so much I didn't want to touch it * unless it was to fix it properly, which seemed a distraction from the * task at hand! -nmatsakis */ adjust_ty(cx, expr.span, expr.id, expr_ty(cx, expr), cx.adjustments.borrow().find(&expr.id), |method_call| cx.method_map.borrow().find(&method_call).map(|method| method.ty)) } pub fn expr_span(cx: &ctxt, id: NodeId) -> Span { match cx.map.find(id) { Some(ast_map::NodeExpr(e)) => { e.span } Some(f) => { cx.sess.bug(format!("Node id {} is not an expr: {:?}", id, f)); } None => { cx.sess.bug(format!("Node id {} is not present \ in the node map", id)); } } } pub fn local_var_name_str(cx: &ctxt, id: NodeId) -> InternedString { match cx.map.find(id) { Some(ast_map::NodeLocal(pat)) => { match pat.node { ast::PatIdent(_, ref path, _) => { token::get_ident(ast_util::path_to_ident(path)) } _ => { cx.sess.bug( format!("Variable id {} maps to {:?}, not local", id, pat)); } } } r => { cx.sess.bug( format!("Variable id {} maps to {:?}, not local", id, r)); } } } pub fn adjust_ty(cx: &ctxt, span: Span, expr_id: ast::NodeId, unadjusted_ty: ty::t, adjustment: Option<&AutoAdjustment>, method_type: |typeck::MethodCall| -> Option) -> ty::t { /*! See `expr_ty_adjusted` */ return match adjustment { Some(adjustment) => { match *adjustment { AutoAddEnv(store) => { match ty::get(unadjusted_ty).sty { ty::ty_bare_fn(ref b) => { ty::mk_closure( cx, ty::ClosureTy {fn_style: b.fn_style, onceness: ast::Many, store: store, bounds: ty::AllBuiltinBounds(), sig: b.sig.clone()}) } ref b => { cx.sess.bug( format!("add_env adjustment on non-bare-fn: \ {:?}", b)); } } } AutoDerefRef(ref adj) => { let mut adjusted_ty = unadjusted_ty; if !ty::type_is_error(adjusted_ty) { for i in range(0, adj.autoderefs) { let method_call = typeck::MethodCall::autoderef(expr_id, i as u32); match method_type(method_call) { Some(method_ty) => { adjusted_ty = ty_fn_ret(method_ty); } None => {} } match deref(adjusted_ty, true) { Some(mt) => { adjusted_ty = mt.ty; } None => { cx.sess.span_bug( span, format!("the {}th autoderef failed: \ {}", i, ty_to_str(cx, adjusted_ty))); } } } } match adj.autoref { None => adjusted_ty, Some(ref autoref) => { match *autoref { AutoPtr(r, m) => { mk_rptr(cx, r, mt { ty: adjusted_ty, mutbl: m }) } AutoBorrowVec(r, m) => { borrow_vec(cx, span, r, m, adjusted_ty) } AutoBorrowVecRef(r, m) => { adjusted_ty = borrow_vec(cx, span, r, m, adjusted_ty); mk_rptr(cx, r, mt { ty: adjusted_ty, mutbl: ast::MutImmutable }) } AutoUnsafe(m) => { mk_ptr(cx, mt {ty: adjusted_ty, mutbl: m}) } AutoBorrowObj(r, m) => { borrow_obj(cx, span, r, m, adjusted_ty) } } } } } AutoObject(store, bounds, def_id, ref substs) => { mk_trait(cx, def_id, substs.clone(), store, bounds) } } } None => unadjusted_ty }; fn borrow_vec(cx: &ctxt, span: Span, r: Region, m: ast::Mutability, ty: ty::t) -> ty::t { match get(ty).sty { ty_uniq(t) | ty_ptr(mt{ty: t, ..}) | ty_rptr(_, mt{ty: t, ..}) => match get(t).sty { ty::ty_vec(mt, None) => ty::mk_slice(cx, r, ty::mt {ty: mt.ty, mutbl: m}), ty::ty_str => ty::mk_str_slice(cx, r, m), _ => { cx.sess.span_bug( span, format!("borrow-vec associated with bad sty: {:?}", get(ty).sty)); } }, ty_vec(mt, Some(_)) => ty::mk_slice(cx, r, ty::mt {ty: mt.ty, mutbl: m}), ref s => { cx.sess.span_bug( span, format!("borrow-vec associated with bad sty: {:?}", s)); } } } fn borrow_obj(cx: &ctxt, span: Span, r: Region, m: ast::Mutability, ty: ty::t) -> ty::t { match get(ty).sty { ty_trait(box ty::TyTrait {def_id, ref substs, bounds, .. }) => { ty::mk_trait(cx, def_id, substs.clone(), RegionTraitStore(r, m), bounds) } ref s => { cx.sess.span_bug( span, format!("borrow-trait-obj associated with bad sty: {:?}", s)); } } } } impl AutoRef { pub fn map_region(&self, f: |Region| -> Region) -> AutoRef { match *self { ty::AutoPtr(r, m) => ty::AutoPtr(f(r), m), ty::AutoBorrowVec(r, m) => ty::AutoBorrowVec(f(r), m), ty::AutoBorrowVecRef(r, m) => ty::AutoBorrowVecRef(f(r), m), ty::AutoUnsafe(m) => ty::AutoUnsafe(m), ty::AutoBorrowObj(r, m) => ty::AutoBorrowObj(f(r), m), } } } pub struct ParamsTy { pub params: Vec, pub ty: t } #[allow(dead_code)] // this may be useful? pub fn expr_ty_params_and_ty(cx: &ctxt, expr: &ast::Expr) -> ParamsTy { ParamsTy { params: node_id_to_type_params(cx, expr.id), ty: node_id_to_type(cx, expr.id) } } pub fn method_call_type_param_defs(tcx: &ctxt, origin: typeck::MethodOrigin) -> Rc> { match origin { typeck::MethodStatic(did) => { // n.b.: When we encode impl methods, the bounds // that we encode include both the impl bounds // and then the method bounds themselves... ty::lookup_item_type(tcx, did).generics.type_param_defs } typeck::MethodParam(typeck::MethodParam { trait_id: trt_id, method_num: n_mth, ..}) | typeck::MethodObject(typeck::MethodObject { trait_id: trt_id, method_num: n_mth, ..}) => { // ...trait methods bounds, in contrast, include only the // method bounds, so we must preprend the tps from the // trait itself. This ought to be harmonized. let trait_type_param_defs = Vec::from_slice(lookup_trait_def(tcx, trt_id).generics.type_param_defs()); Rc::new(trait_type_param_defs.append( ty::trait_method(tcx, trt_id, n_mth).generics.type_param_defs())) } } } pub fn resolve_expr(tcx: &ctxt, expr: &ast::Expr) -> ast::Def { match tcx.def_map.borrow().find(&expr.id) { Some(&def) => def, None => { tcx.sess.span_bug(expr.span, format!( "no def-map entry for expr {:?}", expr.id)); } } } pub fn expr_is_lval(tcx: &ctxt, e: &ast::Expr) -> bool { match expr_kind(tcx, e) { LvalueExpr => true, RvalueDpsExpr | RvalueDatumExpr | RvalueStmtExpr => false } } /// We categorize expressions into three kinds. The distinction between /// lvalue/rvalue is fundamental to the language. The distinction between the /// two kinds of rvalues is an artifact of trans which reflects how we will /// generate code for that kind of expression. See trans/expr.rs for more /// information. pub enum ExprKind { LvalueExpr, RvalueDpsExpr, RvalueDatumExpr, RvalueStmtExpr } pub fn expr_kind(tcx: &ctxt, expr: &ast::Expr) -> ExprKind { if tcx.method_map.borrow().contains_key(&typeck::MethodCall::expr(expr.id)) { // Overloaded operations are generally calls, and hence they are // generated via DPS, but there are two exceptions: return match expr.node { // `a += b` has a unit result. ast::ExprAssignOp(..) => RvalueStmtExpr, // the deref method invoked for `*a` always yields an `&T` ast::ExprUnary(ast::UnDeref, _) => LvalueExpr, // in the general case, result could be any type, use DPS _ => RvalueDpsExpr }; } match expr.node { ast::ExprPath(..) => { match resolve_expr(tcx, expr) { ast::DefVariant(tid, vid, _) => { let variant_info = enum_variant_with_id(tcx, tid, vid); if variant_info.args.len() > 0u { // N-ary variant. RvalueDatumExpr } else { // Nullary variant. RvalueDpsExpr } } ast::DefStruct(_) => { match get(expr_ty(tcx, expr)).sty { ty_bare_fn(..) => RvalueDatumExpr, _ => RvalueDpsExpr } } // Fn pointers are just scalar values. ast::DefFn(..) | ast::DefStaticMethod(..) => RvalueDatumExpr, // Note: there is actually a good case to be made that // DefArg's, particularly those of immediate type, ought to // considered rvalues. ast::DefStatic(..) | ast::DefBinding(..) | ast::DefUpvar(..) | ast::DefArg(..) | ast::DefLocal(..) => LvalueExpr, def => { tcx.sess.span_bug(expr.span, format!( "uncategorized def for expr {:?}: {:?}", expr.id, def)); } } } ast::ExprUnary(ast::UnDeref, _) | ast::ExprField(..) | ast::ExprIndex(..) => { LvalueExpr } ast::ExprCall(..) | ast::ExprMethodCall(..) | ast::ExprStruct(..) | ast::ExprTup(..) | ast::ExprIf(..) | ast::ExprMatch(..) | ast::ExprFnBlock(..) | ast::ExprProc(..) | ast::ExprBlock(..) | ast::ExprRepeat(..) | ast::ExprVstore(_, ast::ExprVstoreSlice) | ast::ExprVstore(_, ast::ExprVstoreMutSlice) | ast::ExprVec(..) => { RvalueDpsExpr } ast::ExprLit(lit) if lit_is_str(lit) => { RvalueDpsExpr } ast::ExprCast(..) => { match tcx.node_types.borrow().find(&(expr.id as uint)) { Some(&t) => { if type_is_trait(t) { RvalueDpsExpr } else { RvalueDatumExpr } } None => { // Technically, it should not happen that the expr is not // present within the table. However, it DOES happen // during type check, because the final types from the // expressions are not yet recorded in the tcx. At that // time, though, we are only interested in knowing lvalue // vs rvalue. It would be better to base this decision on // the AST type in cast node---but (at the time of this // writing) it's not easy to distinguish casts to traits // from other casts based on the AST. This should be // easier in the future, when casts to traits // would like @Foo, Box, or &Foo. RvalueDatumExpr } } } ast::ExprBreak(..) | ast::ExprAgain(..) | ast::ExprRet(..) | ast::ExprWhile(..) | ast::ExprLoop(..) | ast::ExprAssign(..) | ast::ExprInlineAsm(..) | ast::ExprAssignOp(..) => { RvalueStmtExpr } ast::ExprForLoop(..) => fail!("non-desugared expr_for_loop"), ast::ExprLit(_) | // Note: LitStr is carved out above ast::ExprUnary(..) | ast::ExprAddrOf(..) | ast::ExprBinary(..) | ast::ExprVstore(_, ast::ExprVstoreUniq) => { RvalueDatumExpr } ast::ExprBox(place, _) => { // Special case `Box` for now: let definition = match tcx.def_map.borrow().find(&place.id) { Some(&def) => def, None => fail!("no def for place"), }; let def_id = ast_util::def_id_of_def(definition); match tcx.lang_items.items.get(ExchangeHeapLangItem as uint) { &Some(item_def_id) if def_id == item_def_id => { RvalueDatumExpr } &Some(_) | &None => RvalueDpsExpr, } } ast::ExprParen(e) => expr_kind(tcx, e), ast::ExprMac(..) => { tcx.sess.span_bug( expr.span, "macro expression remains after expansion"); } } } pub fn stmt_node_id(s: &ast::Stmt) -> ast::NodeId { match s.node { ast::StmtDecl(_, id) | StmtExpr(_, id) | StmtSemi(_, id) => { return id; } ast::StmtMac(..) => fail!("unexpanded macro in trans") } } pub fn field_idx_strict(tcx: &ctxt, name: ast::Name, fields: &[field]) -> uint { let mut i = 0u; for f in fields.iter() { if f.ident.name == name { return i; } i += 1u; } tcx.sess.bug(format!( "no field named `{}` found in the list of fields `{:?}`", token::get_name(name), fields.iter().map(|f| token::get_ident(f.ident).get().to_str()).collect::>())); } pub fn method_idx(id: ast::Ident, meths: &[Rc]) -> Option { meths.iter().position(|m| m.ident == id) } /// Returns a vector containing the indices of all type parameters that appear /// in `ty`. The vector may contain duplicates. Probably should be converted /// to a bitset or some other representation. pub fn param_tys_in_type(ty: t) -> Vec { let mut rslt = Vec::new(); walk_ty(ty, |ty| { match get(ty).sty { ty_param(p) => { rslt.push(p); } _ => () } }); rslt } pub fn ty_sort_str(cx: &ctxt, t: t) -> ~str { match get(t).sty { ty_nil | ty_bot | ty_bool | ty_char | ty_int(_) | ty_uint(_) | ty_float(_) | ty_str => { ::util::ppaux::ty_to_str(cx, t) } ty_enum(id, _) => format!("enum {}", item_path_str(cx, id)), ty_box(_) => "@-ptr".to_owned(), ty_uniq(_) => "box".to_owned(), ty_vec(_, _) => "vector".to_owned(), ty_ptr(_) => "*-ptr".to_owned(), ty_rptr(_, _) => "&-ptr".to_owned(), ty_bare_fn(_) => "extern fn".to_owned(), ty_closure(_) => "fn".to_owned(), ty_trait(ref inner) => format!("trait {}", item_path_str(cx, inner.def_id)), ty_struct(id, _) => format!("struct {}", item_path_str(cx, id)), ty_tup(_) => "tuple".to_owned(), ty_infer(TyVar(_)) => "inferred type".to_owned(), ty_infer(IntVar(_)) => "integral variable".to_owned(), ty_infer(FloatVar(_)) => "floating-point variable".to_owned(), ty_param(_) => "type parameter".to_owned(), ty_self(_) => "self".to_owned(), ty_err => "type error".to_owned() } } pub fn type_err_to_str(cx: &ctxt, err: &type_err) -> ~str { /*! * * Explains the source of a type err in a short, * human readable way. This is meant to be placed in * parentheses after some larger message. You should * also invoke `note_and_explain_type_err()` afterwards * to present additional details, particularly when * it comes to lifetime-related errors. */ fn tstore_to_closure(s: &TraitStore) -> ~str { match s { &UniqTraitStore => "proc".to_owned(), &RegionTraitStore(..) => "closure".to_owned() } } match *err { terr_mismatch => "types differ".to_owned(), terr_fn_style_mismatch(values) => { format!("expected {} fn but found {} fn", values.expected.to_str(), values.found.to_str()) } terr_abi_mismatch(values) => { format!("expected {} fn but found {} fn", values.expected.to_str(), values.found.to_str()) } terr_onceness_mismatch(values) => { format!("expected {} fn but found {} fn", values.expected.to_str(), values.found.to_str()) } terr_sigil_mismatch(values) => { format!("expected {}, found {}", tstore_to_closure(&values.expected), tstore_to_closure(&values.found)) } terr_mutability => "values differ in mutability".to_owned(), terr_box_mutability => "boxed values differ in mutability".to_owned(), terr_vec_mutability => "vectors differ in mutability".to_owned(), terr_ptr_mutability => "pointers differ in mutability".to_owned(), terr_ref_mutability => "references differ in mutability".to_owned(), terr_ty_param_size(values) => { format!("expected a type with {} type params \ but found one with {} type params", values.expected, values.found) } terr_tuple_size(values) => { format!("expected a tuple with {} elements \ but found one with {} elements", values.expected, values.found) } terr_record_size(values) => { format!("expected a record with {} fields \ but found one with {} fields", values.expected, values.found) } terr_record_mutability => { "record elements differ in mutability".to_owned() } terr_record_fields(values) => { format!("expected a record with field `{}` but found one with field \ `{}`", token::get_ident(values.expected), token::get_ident(values.found)) } terr_arg_count => "incorrect number of function parameters".to_owned(), terr_regions_does_not_outlive(..) => { format!("lifetime mismatch") } terr_regions_not_same(..) => { format!("lifetimes are not the same") } terr_regions_no_overlap(..) => { format!("lifetimes do not intersect") } terr_regions_insufficiently_polymorphic(br, _) => { format!("expected bound lifetime parameter {}, \ but found concrete lifetime", bound_region_ptr_to_str(cx, br)) } terr_regions_overly_polymorphic(br, _) => { format!("expected concrete lifetime, \ but found bound lifetime parameter {}", bound_region_ptr_to_str(cx, br)) } terr_trait_stores_differ(_, ref values) => { format!("trait storage differs: expected `{}` but found `{}`", trait_store_to_str(cx, (*values).expected), trait_store_to_str(cx, (*values).found)) } terr_sorts(values) => { format!("expected {} but found {}", ty_sort_str(cx, values.expected), ty_sort_str(cx, values.found)) } terr_traits(values) => { format!("expected trait `{}` but found trait `{}`", item_path_str(cx, values.expected), item_path_str(cx, values.found)) } terr_builtin_bounds(values) => { if values.expected.is_empty() { format!("expected no bounds but found `{}`", values.found.user_string(cx)) } else if values.found.is_empty() { format!("expected bounds `{}` but found no bounds", values.expected.user_string(cx)) } else { format!("expected bounds `{}` but found bounds `{}`", values.expected.user_string(cx), values.found.user_string(cx)) } } terr_integer_as_char => { format!("expected an integral type but found `char`") } terr_int_mismatch(ref values) => { format!("expected `{}` but found `{}`", values.expected.to_str(), values.found.to_str()) } terr_float_mismatch(ref values) => { format!("expected `{}` but found `{}`", values.expected.to_str(), values.found.to_str()) } terr_variadic_mismatch(ref values) => { format!("expected {} fn but found {} function", if values.expected { "variadic" } else { "non-variadic" }, if values.found { "variadic" } else { "non-variadic" }) } } } pub fn note_and_explain_type_err(cx: &ctxt, err: &type_err) { match *err { terr_regions_does_not_outlive(subregion, superregion) => { note_and_explain_region(cx, "", subregion, "..."); note_and_explain_region(cx, "...does not necessarily outlive ", superregion, ""); } terr_regions_not_same(region1, region2) => { note_and_explain_region(cx, "", region1, "..."); note_and_explain_region(cx, "...is not the same lifetime as ", region2, ""); } terr_regions_no_overlap(region1, region2) => { note_and_explain_region(cx, "", region1, "..."); note_and_explain_region(cx, "...does not overlap ", region2, ""); } terr_regions_insufficiently_polymorphic(_, conc_region) => { note_and_explain_region(cx, "concrete lifetime that was found is ", conc_region, ""); } terr_regions_overly_polymorphic(_, conc_region) => { note_and_explain_region(cx, "expected concrete lifetime is ", conc_region, ""); } _ => {} } } pub fn provided_source(cx: &ctxt, id: ast::DefId) -> Option { cx.provided_method_sources.borrow().find(&id).map(|x| *x) } pub fn provided_trait_methods(cx: &ctxt, id: ast::DefId) -> Vec> { if is_local(id) { match cx.map.find(id.node) { Some(ast_map::NodeItem(item)) => { match item.node { ItemTrait(_, _, _, ref ms) => { let (_, p) = ast_util::split_trait_methods(ms.as_slice()); p.iter().map(|m| method(cx, ast_util::local_def(m.id))).collect() } _ => cx.sess.bug(format!("provided_trait_methods: `{}` is not a trait", id)) } } _ => cx.sess.bug(format!("provided_trait_methods: `{}` is not a trait", id)) } } else { csearch::get_provided_trait_methods(cx, id) } } pub fn trait_supertraits(cx: &ctxt, id: ast::DefId) -> Rc>> { // Check the cache. match cx.supertraits.borrow().find(&id) { Some(trait_refs) => { return trait_refs.clone(); } None => {} // Continue. } // Not in the cache. It had better be in the metadata, which means it // shouldn't be local. assert!(!is_local(id)); // Get the supertraits out of the metadata and create the // TraitRef for each. let result = Rc::new(csearch::get_supertraits(cx, id)); cx.supertraits.borrow_mut().insert(id, result.clone()); result } pub fn trait_ref_supertraits(cx: &ctxt, trait_ref: &ty::TraitRef) -> Vec> { let supertrait_refs = trait_supertraits(cx, trait_ref.def_id); supertrait_refs.iter().map( |supertrait_ref| supertrait_ref.subst(cx, &trait_ref.substs)).collect() } fn lookup_locally_or_in_crate_store( descr: &str, def_id: ast::DefId, map: &mut DefIdMap, load_external: || -> V) -> V { /*! * Helper for looking things up in the various maps * that are populated during typeck::collect (e.g., * `cx.methods`, `cx.tcache`, etc). All of these share * the pattern that if the id is local, it should have * been loaded into the map by the `typeck::collect` phase. * If the def-id is external, then we have to go consult * the crate loading code (and cache the result for the future). */ match map.find_copy(&def_id) { Some(v) => { return v; } None => { } } if def_id.krate == ast::LOCAL_CRATE { fail!("No def'n found for {:?} in tcx.{}", def_id, descr); } let v = load_external(); map.insert(def_id, v.clone()); v } pub fn trait_method(cx: &ctxt, trait_did: ast::DefId, idx: uint) -> Rc { let method_def_id = *ty::trait_method_def_ids(cx, trait_did).get(idx); ty::method(cx, method_def_id) } pub fn trait_methods(cx: &ctxt, trait_did: ast::DefId) -> Rc>> { let mut trait_methods = cx.trait_methods_cache.borrow_mut(); match trait_methods.find_copy(&trait_did) { Some(methods) => methods, None => { let def_ids = ty::trait_method_def_ids(cx, trait_did); let methods: Rc>> = Rc::new(def_ids.iter().map(|d| { ty::method(cx, *d) }).collect()); trait_methods.insert(trait_did, methods.clone()); methods } } } pub fn method(cx: &ctxt, id: ast::DefId) -> Rc { lookup_locally_or_in_crate_store("methods", id, &mut *cx.methods.borrow_mut(), || { Rc::new(csearch::get_method(cx, id)) }) } pub fn trait_method_def_ids(cx: &ctxt, id: ast::DefId) -> Rc> { lookup_locally_or_in_crate_store("trait_method_def_ids", id, &mut *cx.trait_method_def_ids.borrow_mut(), || { Rc::new(csearch::get_trait_method_def_ids(&cx.sess.cstore, id)) }) } pub fn impl_trait_ref(cx: &ctxt, id: ast::DefId) -> Option> { match cx.impl_trait_cache.borrow().find(&id) { Some(ret) => { return ret.clone(); } None => {} } let ret = if id.krate == ast::LOCAL_CRATE { debug!("(impl_trait_ref) searching for trait impl {:?}", id); match cx.map.find(id.node) { Some(ast_map::NodeItem(item)) => { match item.node { ast::ItemImpl(_, ref opt_trait, _, _) => { match opt_trait { &Some(ref t) => { Some(ty::node_id_to_trait_ref(cx, t.ref_id)) } &None => None } } _ => None } } _ => None } } else { csearch::get_impl_trait(cx, id) }; cx.impl_trait_cache.borrow_mut().insert(id, ret.clone()); ret } pub fn trait_ref_to_def_id(tcx: &ctxt, tr: &ast::TraitRef) -> ast::DefId { let def = *tcx.def_map.borrow() .find(&tr.ref_id) .expect("no def-map entry for trait"); ast_util::def_id_of_def(def) } pub fn try_add_builtin_trait(tcx: &ctxt, trait_def_id: ast::DefId, builtin_bounds: &mut BuiltinBounds) -> bool { //! Checks whether `trait_ref` refers to one of the builtin //! traits, like `Send`, and adds the corresponding //! bound to the set `builtin_bounds` if so. Returns true if `trait_ref` //! is a builtin trait. match tcx.lang_items.to_builtin_kind(trait_def_id) { Some(bound) => { builtin_bounds.add(bound); true } None => false } } pub fn ty_to_def_id(ty: t) -> Option { match get(ty).sty { ty_trait(box TyTrait { def_id: id, .. }) | ty_struct(id, _) | ty_enum(id, _) => Some(id), _ => None } } // Enum information #[deriving(Clone)] pub struct VariantInfo { pub args: Vec, pub arg_names: Option >, pub ctor_ty: t, pub name: ast::Ident, pub id: ast::DefId, pub disr_val: Disr, pub vis: Visibility } impl VariantInfo { /// Creates a new VariantInfo from the corresponding ast representation. /// /// Does not do any caching of the value in the type context. pub fn from_ast_variant(cx: &ctxt, ast_variant: &ast::Variant, discriminant: Disr) -> VariantInfo { let ctor_ty = node_id_to_type(cx, ast_variant.node.id); match ast_variant.node.kind { ast::TupleVariantKind(ref args) => { let arg_tys = if args.len() > 0 { ty_fn_args(ctor_ty).iter().map(|a| *a).collect() } else { Vec::new() }; return VariantInfo { args: arg_tys, arg_names: None, ctor_ty: ctor_ty, name: ast_variant.node.name, id: ast_util::local_def(ast_variant.node.id), disr_val: discriminant, vis: ast_variant.node.vis }; }, ast::StructVariantKind(ref struct_def) => { let fields: &[StructField] = struct_def.fields.as_slice(); assert!(fields.len() > 0); let arg_tys = ty_fn_args(ctor_ty).iter().map(|a| *a).collect(); let arg_names = fields.iter().map(|field| { match field.node.kind { NamedField(ident, _) => ident, UnnamedField(..) => cx.sess.bug( "enum_variants: all fields in struct must have a name") } }).collect(); return VariantInfo { args: arg_tys, arg_names: Some(arg_names), ctor_ty: ctor_ty, name: ast_variant.node.name, id: ast_util::local_def(ast_variant.node.id), disr_val: discriminant, vis: ast_variant.node.vis }; } } } } pub fn substd_enum_variants(cx: &ctxt, id: ast::DefId, substs: &substs) -> Vec> { enum_variants(cx, id).iter().map(|variant_info| { let substd_args = variant_info.args.iter() .map(|aty| subst(cx, substs, *aty)).collect(); let substd_ctor_ty = subst(cx, substs, variant_info.ctor_ty); Rc::new(VariantInfo { args: substd_args, ctor_ty: substd_ctor_ty, ..(**variant_info).clone() }) }).collect() } pub fn item_path_str(cx: &ctxt, id: ast::DefId) -> ~str { with_path(cx, id, |path| ast_map::path_to_str(path)).to_owned() } pub enum DtorKind { NoDtor, TraitDtor(DefId, bool) } impl DtorKind { pub fn is_not_present(&self) -> bool { match *self { NoDtor => true, _ => false } } pub fn is_present(&self) -> bool { !self.is_not_present() } pub fn has_drop_flag(&self) -> bool { match self { &NoDtor => false, &TraitDtor(_, flag) => flag } } } /* If struct_id names a struct with a dtor, return Some(the dtor's id). Otherwise return none. */ pub fn ty_dtor(cx: &ctxt, struct_id: DefId) -> DtorKind { match cx.destructor_for_type.borrow().find(&struct_id) { Some(&method_def_id) => { let flag = !has_attr(cx, struct_id, "unsafe_no_drop_flag"); TraitDtor(method_def_id, flag) } None => NoDtor, } } pub fn has_dtor(cx: &ctxt, struct_id: DefId) -> bool { ty_dtor(cx, struct_id).is_present() } pub fn with_path(cx: &ctxt, id: ast::DefId, f: |ast_map::PathElems| -> T) -> T { if id.krate == ast::LOCAL_CRATE { cx.map.with_path(id.node, f) } else { f(ast_map::Values(csearch::get_item_path(cx, id).iter()).chain(None)) } } pub fn enum_is_univariant(cx: &ctxt, id: ast::DefId) -> bool { enum_variants(cx, id).len() == 1 } pub fn type_is_empty(cx: &ctxt, t: t) -> bool { match ty::get(t).sty { ty_enum(did, _) => (*enum_variants(cx, did)).is_empty(), _ => false } } pub fn enum_variants(cx: &ctxt, id: ast::DefId) -> Rc>> { match cx.enum_var_cache.borrow().find(&id) { Some(variants) => return variants.clone(), _ => { /* fallthrough */ } } let result = if ast::LOCAL_CRATE != id.krate { Rc::new(csearch::get_enum_variants(cx, id)) } else { /* Although both this code and check_enum_variants in typeck/check call eval_const_expr, it should never get called twice for the same expr, since check_enum_variants also updates the enum_var_cache */ match cx.map.get(id.node) { ast_map::NodeItem(item) => { match item.node { ast::ItemEnum(ref enum_definition, _) => { let mut last_discriminant: Option = None; Rc::new(enum_definition.variants.iter().map(|&variant| { let mut discriminant = match last_discriminant { Some(val) => val + 1, None => INITIAL_DISCRIMINANT_VALUE }; match variant.node.disr_expr { Some(e) => match const_eval::eval_const_expr_partial(cx, e) { Ok(const_eval::const_int(val)) => { discriminant = val as Disr } Ok(const_eval::const_uint(val)) => { discriminant = val as Disr } Ok(_) => { cx.sess .span_err(e.span, "expected signed integer constant"); } Err(ref err) => { cx.sess .span_err(e.span, format!("expected constant: {}", *err)); } }, None => {} }; last_discriminant = Some(discriminant); Rc::new(VariantInfo::from_ast_variant(cx, variant, discriminant)) }).collect()) } _ => { cx.sess.bug("enum_variants: id not bound to an enum") } } } _ => cx.sess.bug("enum_variants: id not bound to an enum") } }; cx.enum_var_cache.borrow_mut().insert(id, result.clone()); result } // Returns information about the enum variant with the given ID: pub fn enum_variant_with_id(cx: &ctxt, enum_id: ast::DefId, variant_id: ast::DefId) -> Rc { enum_variants(cx, enum_id).iter() .find(|variant| variant.id == variant_id) .expect("enum_variant_with_id(): no variant exists with that ID") .clone() } // If the given item is in an external crate, looks up its type and adds it to // the type cache. Returns the type parameters and type. pub fn lookup_item_type(cx: &ctxt, did: ast::DefId) -> ty_param_bounds_and_ty { lookup_locally_or_in_crate_store( "tcache", did, &mut *cx.tcache.borrow_mut(), || csearch::get_type(cx, did)) } pub fn lookup_impl_vtables(cx: &ctxt, did: ast::DefId) -> typeck::impl_res { lookup_locally_or_in_crate_store( "impl_vtables", did, &mut *cx.impl_vtables.borrow_mut(), || csearch::get_impl_vtables(cx, did) ) } /// Given the did of a trait, returns its canonical trait ref. pub fn lookup_trait_def(cx: &ctxt, did: ast::DefId) -> Rc { let mut trait_defs = cx.trait_defs.borrow_mut(); match trait_defs.find_copy(&did) { Some(trait_def) => { // The item is in this crate. The caller should have added it to the // type cache already trait_def } None => { assert!(did.krate != ast::LOCAL_CRATE); let trait_def = Rc::new(csearch::get_trait_def(cx, did)); trait_defs.insert(did, trait_def.clone()); trait_def } } } /// Iterate over meta_items of a definition. // (This should really be an iterator, but that would require csearch and // decoder to use iterators instead of higher-order functions.) pub fn each_attr(tcx: &ctxt, did: DefId, f: |@ast::MetaItem| -> bool) -> bool { if is_local(did) { let item = tcx.map.expect_item(did.node); item.attrs.iter().advance(|attr| f(attr.node.value)) } else { let mut cont = true; csearch::get_item_attrs(&tcx.sess.cstore, did, |meta_items| { if cont { cont = meta_items.iter().advance(|ptrptr| f(*ptrptr)); } }); cont } } /// Determine whether an item is annotated with an attribute pub fn has_attr(tcx: &ctxt, did: DefId, attr: &str) -> bool { let mut found = false; each_attr(tcx, did, |item| { if item.name().equiv(&attr) { found = true; false } else { true } }); found } /// Determine whether an item is annotated with `#[packed]` pub fn lookup_packed(tcx: &ctxt, did: DefId) -> bool { has_attr(tcx, did, "packed") } /// Determine whether an item is annotated with `#[simd]` pub fn lookup_simd(tcx: &ctxt, did: DefId) -> bool { has_attr(tcx, did, "simd") } // Obtain the representation annotation for a definition. pub fn lookup_repr_hint(tcx: &ctxt, did: DefId) -> attr::ReprAttr { let mut acc = attr::ReprAny; ty::each_attr(tcx, did, |meta| { acc = attr::find_repr_attr(tcx.sess.diagnostic(), meta, acc); true }); return acc; } // Look up a field ID, whether or not it's local // Takes a list of type substs in case the struct is generic pub fn lookup_field_type(tcx: &ctxt, struct_id: DefId, id: DefId, substs: &substs) -> ty::t { let t = if id.krate == ast::LOCAL_CRATE { node_id_to_type(tcx, id.node) } else { let mut tcache = tcx.tcache.borrow_mut(); match tcache.find(&id) { Some(&ty_param_bounds_and_ty {ty, ..}) => ty, None => { let tpt = csearch::get_field_type(tcx, struct_id, id); tcache.insert(id, tpt.clone()); tpt.ty } } }; subst(tcx, substs, t) } // Lookup all ancestor structs of a struct indicated by did. That is the reflexive, // transitive closure of doing a single lookup in cx.superstructs. fn each_super_struct(cx: &ctxt, mut did: ast::DefId, f: |ast::DefId|) { let superstructs = cx.superstructs.borrow(); loop { f(did); match superstructs.find(&did) { Some(&Some(def_id)) => { did = def_id; }, Some(&None) => break, None => { cx.sess.bug( format!("ID not mapped to super-struct: {}", cx.map.node_to_str(did.node))); } } } } // Look up the list of field names and IDs for a given struct. // Fails if the id is not bound to a struct. pub fn lookup_struct_fields(cx: &ctxt, did: ast::DefId) -> Vec { if did.krate == ast::LOCAL_CRATE { // We store the fields which are syntactically in each struct in cx. So // we have to walk the inheritance chain of the struct to get all the // structs (explicit and inherited) for a struct. If this is expensive // we could cache the whole list of fields here. let struct_fields = cx.struct_fields.borrow(); let mut results: SmallVector<&[field_ty]> = SmallVector::zero(); each_super_struct(cx, did, |s| { match struct_fields.find(&s) { Some(fields) => results.push(fields.as_slice()), _ => { cx.sess.bug( format!("ID not mapped to struct fields: {}", cx.map.node_to_str(did.node))); } } }); let len = results.as_slice().iter().map(|x| x.len()).sum(); let mut result: Vec = Vec::with_capacity(len); result.extend(results.as_slice().iter().flat_map(|rs| rs.iter().map(|&f| f))); assert!(result.len() == len); result } else { csearch::get_struct_fields(&cx.sess.cstore, did) } } pub fn lookup_struct_field(cx: &ctxt, parent: ast::DefId, field_id: ast::DefId) -> field_ty { let r = lookup_struct_fields(cx, parent); match r.iter().find(|f| f.id.node == field_id.node) { Some(t) => *t, None => cx.sess.bug("struct ID not found in parent's fields") } } // Returns a list of fields corresponding to the struct's items. trans uses // this. Takes a list of substs with which to instantiate field types. pub fn struct_fields(cx: &ctxt, did: ast::DefId, substs: &substs) -> Vec { lookup_struct_fields(cx, did).iter().map(|f| { field { // FIXME #6993: change type of field to Name and get rid of new() ident: ast::Ident::new(f.name), mt: mt { ty: lookup_field_type(cx, did, f.id, substs), mutbl: MutImmutable } } }).collect() } pub fn is_binopable(cx: &ctxt, ty: t, op: ast::BinOp) -> bool { static tycat_other: int = 0; static tycat_bool: int = 1; static tycat_char: int = 2; static tycat_int: int = 3; static tycat_float: int = 4; static tycat_bot: int = 5; static tycat_raw_ptr: int = 6; static opcat_add: int = 0; static opcat_sub: int = 1; static opcat_mult: int = 2; static opcat_shift: int = 3; static opcat_rel: int = 4; static opcat_eq: int = 5; static opcat_bit: int = 6; static opcat_logic: int = 7; static opcat_mod: int = 8; fn opcat(op: ast::BinOp) -> int { match op { ast::BiAdd => opcat_add, ast::BiSub => opcat_sub, ast::BiMul => opcat_mult, ast::BiDiv => opcat_mult, ast::BiRem => opcat_mod, ast::BiAnd => opcat_logic, ast::BiOr => opcat_logic, ast::BiBitXor => opcat_bit, ast::BiBitAnd => opcat_bit, ast::BiBitOr => opcat_bit, ast::BiShl => opcat_shift, ast::BiShr => opcat_shift, ast::BiEq => opcat_eq, ast::BiNe => opcat_eq, ast::BiLt => opcat_rel, ast::BiLe => opcat_rel, ast::BiGe => opcat_rel, ast::BiGt => opcat_rel } } fn tycat(cx: &ctxt, ty: t) -> int { if type_is_simd(cx, ty) { return tycat(cx, simd_type(cx, ty)) } match get(ty).sty { ty_char => tycat_char, ty_bool => tycat_bool, ty_int(_) | ty_uint(_) | ty_infer(IntVar(_)) => tycat_int, ty_float(_) | ty_infer(FloatVar(_)) => tycat_float, ty_bot => tycat_bot, ty_ptr(_) => tycat_raw_ptr, _ => tycat_other } } static t: bool = true; static f: bool = false; let tbl = [ // +, -, *, shift, rel, ==, bit, logic, mod /*other*/ [f, f, f, f, f, f, f, f, f], /*bool*/ [f, f, f, f, t, t, t, t, f], /*char*/ [f, f, f, f, t, t, f, f, f], /*int*/ [t, t, t, t, t, t, t, f, t], /*float*/ [t, t, t, f, t, t, f, f, f], /*bot*/ [t, t, t, t, t, t, t, t, t], /*raw ptr*/ [f, f, f, f, t, t, f, f, f]]; return tbl[tycat(cx, ty) as uint ][opcat(op) as uint]; } /// Returns an equivalent type with all the typedefs and self regions removed. pub fn normalize_ty(cx: &ctxt, t: t) -> t { let u = TypeNormalizer(cx).fold_ty(t); return u; struct TypeNormalizer<'a>(&'a ctxt); impl<'a> TypeFolder for TypeNormalizer<'a> { fn tcx<'a>(&'a self) -> &'a ctxt { let TypeNormalizer(c) = *self; c } fn fold_ty(&mut self, t: ty::t) -> ty::t { match self.tcx().normalized_cache.borrow().find_copy(&t) { None => {} Some(u) => return u } let t_norm = ty_fold::super_fold_ty(self, t); self.tcx().normalized_cache.borrow_mut().insert(t, t_norm); return t_norm; } fn fold_region(&mut self, _: ty::Region) -> ty::Region { ty::ReStatic } fn fold_substs(&mut self, substs: &substs) -> substs { substs { regions: ErasedRegions, self_ty: ty_fold::fold_opt_ty(self, substs.self_ty), tps: ty_fold::fold_ty_vec(self, substs.tps.as_slice()) } } fn fold_sig(&mut self, sig: &ty::FnSig) -> ty::FnSig { // The binder-id is only relevant to bound regions, which // are erased at trans time. ty::FnSig { binder_id: ast::DUMMY_NODE_ID, inputs: ty_fold::fold_ty_vec(self, sig.inputs.as_slice()), output: self.fold_ty(sig.output), variadic: sig.variadic, } } } } pub trait ExprTyProvider { fn expr_ty(&self, ex: &ast::Expr) -> t; fn ty_ctxt<'a>(&'a self) -> &'a ctxt; } impl ExprTyProvider for ctxt { fn expr_ty(&self, ex: &ast::Expr) -> t { expr_ty(self, ex) } fn ty_ctxt<'a>(&'a self) -> &'a ctxt { self } } // Returns the repeat count for a repeating vector expression. pub fn eval_repeat_count(tcx: &T, count_expr: &ast::Expr) -> uint { match const_eval::eval_const_expr_partial(tcx, count_expr) { Ok(ref const_val) => match *const_val { const_eval::const_int(count) => if count < 0 { tcx.ty_ctxt().sess.span_err(count_expr.span, "expected positive integer for \ repeat count but found negative integer"); return 0; } else { return count as uint }, const_eval::const_uint(count) => return count as uint, const_eval::const_float(count) => { tcx.ty_ctxt().sess.span_err(count_expr.span, "expected positive integer for \ repeat count but found float"); return count as uint; } const_eval::const_str(_) => { tcx.ty_ctxt().sess.span_err(count_expr.span, "expected positive integer for \ repeat count but found string"); return 0; } const_eval::const_bool(_) => { tcx.ty_ctxt().sess.span_err(count_expr.span, "expected positive integer for \ repeat count but found boolean"); return 0; } const_eval::const_binary(_) => { tcx.ty_ctxt().sess.span_err(count_expr.span, "expected positive integer for \ repeat count but found binary array"); return 0; } }, Err(..) => { tcx.ty_ctxt().sess.span_err(count_expr.span, "expected constant integer for repeat count \ but found variable"); return 0; } } } // Iterate over a type parameter's bounded traits and any supertraits // of those traits, ignoring kinds. // Here, the supertraits are the transitive closure of the supertrait // relation on the supertraits from each bounded trait's constraint // list. pub fn each_bound_trait_and_supertraits(tcx: &ctxt, bounds: &[Rc], f: |Rc| -> bool) -> bool { for bound_trait_ref in bounds.iter() { let mut supertrait_set = HashMap::new(); let mut trait_refs = Vec::new(); let mut i = 0; // Seed the worklist with the trait from the bound supertrait_set.insert(bound_trait_ref.def_id, ()); trait_refs.push(bound_trait_ref.clone()); // Add the given trait ty to the hash map while i < trait_refs.len() { debug!("each_bound_trait_and_supertraits(i={:?}, trait_ref={})", i, trait_refs.get(i).repr(tcx)); if !f(trait_refs.get(i).clone()) { return false; } // Add supertraits to supertrait_set let supertrait_refs = trait_ref_supertraits(tcx, &**trait_refs.get(i)); for supertrait_ref in supertrait_refs.iter() { debug!("each_bound_trait_and_supertraits(supertrait_ref={})", supertrait_ref.repr(tcx)); let d_id = supertrait_ref.def_id; if !supertrait_set.contains_key(&d_id) { // FIXME(#5527) Could have same trait multiple times supertrait_set.insert(d_id, ()); trait_refs.push(supertrait_ref.clone()); } } i += 1; } } return true; } pub fn get_tydesc_ty(tcx: &ctxt) -> Result { tcx.lang_items.require(TyDescStructLangItem).map(|tydesc_lang_item| { tcx.intrinsic_defs.borrow().find_copy(&tydesc_lang_item) .expect("Failed to resolve TyDesc") }) } pub fn get_opaque_ty(tcx: &ctxt) -> Result { tcx.lang_items.require(OpaqueStructLangItem).map(|opaque_lang_item| { tcx.intrinsic_defs.borrow().find_copy(&opaque_lang_item) .expect("Failed to resolve Opaque") }) } pub fn visitor_object_ty(tcx: &ctxt, region: ty::Region) -> Result<(Rc, t), ~str> { let trait_lang_item = match tcx.lang_items.require(TyVisitorTraitLangItem) { Ok(id) => id, Err(s) => { return Err(s); } }; let substs = substs { regions: ty::NonerasedRegions(OwnedSlice::empty()), self_ty: None, tps: Vec::new() }; let trait_ref = Rc::new(TraitRef { def_id: trait_lang_item, substs: substs }); Ok((trait_ref.clone(), mk_trait(tcx, trait_ref.def_id, trait_ref.substs.clone(), RegionTraitStore(region, ast::MutMutable), EmptyBuiltinBounds()))) } pub fn item_variances(tcx: &ctxt, item_id: ast::DefId) -> Rc { lookup_locally_or_in_crate_store( "item_variance_map", item_id, &mut *tcx.item_variance_map.borrow_mut(), || Rc::new(csearch::get_item_variances(&tcx.sess.cstore, item_id))) } /// Records a trait-to-implementation mapping. pub fn record_trait_implementation(tcx: &ctxt, trait_def_id: DefId, impl_def_id: DefId) { match tcx.trait_impls.borrow().find(&trait_def_id) { Some(impls_for_trait) => { impls_for_trait.borrow_mut().push(impl_def_id); return; } None => {} } tcx.trait_impls.borrow_mut().insert(trait_def_id, Rc::new(RefCell::new(vec!(impl_def_id)))); } /// Populates the type context with all the implementations for the given type /// if necessary. pub fn populate_implementations_for_type_if_necessary(tcx: &ctxt, type_id: ast::DefId) { if type_id.krate == LOCAL_CRATE { return } if tcx.populated_external_types.borrow().contains(&type_id) { return } csearch::each_implementation_for_type(&tcx.sess.cstore, type_id, |impl_def_id| { let methods = csearch::get_impl_methods(&tcx.sess.cstore, impl_def_id); // Record the trait->implementation mappings, if applicable. let associated_traits = csearch::get_impl_trait(tcx, impl_def_id); for trait_ref in associated_traits.iter() { record_trait_implementation(tcx, trait_ref.def_id, impl_def_id); } // For any methods that use a default implementation, add them to // the map. This is a bit unfortunate. for &method_def_id in methods.iter() { for &source in ty::method(tcx, method_def_id).provided_source.iter() { tcx.provided_method_sources.borrow_mut().insert(method_def_id, source); } } // Store the implementation info. tcx.impl_methods.borrow_mut().insert(impl_def_id, methods); // If this is an inherent implementation, record it. if associated_traits.is_none() { match tcx.inherent_impls.borrow().find(&type_id) { Some(implementation_list) => { implementation_list.borrow_mut().push(impl_def_id); return; } None => {} } tcx.inherent_impls.borrow_mut().insert(type_id, Rc::new(RefCell::new(vec!(impl_def_id)))); } }); tcx.populated_external_types.borrow_mut().insert(type_id); } /// Populates the type context with all the implementations for the given /// trait if necessary. pub fn populate_implementations_for_trait_if_necessary( tcx: &ctxt, trait_id: ast::DefId) { if trait_id.krate == LOCAL_CRATE { return } if tcx.populated_external_traits.borrow().contains(&trait_id) { return } csearch::each_implementation_for_trait(&tcx.sess.cstore, trait_id, |implementation_def_id| { let methods = csearch::get_impl_methods(&tcx.sess.cstore, implementation_def_id); // Record the trait->implementation mapping. record_trait_implementation(tcx, trait_id, implementation_def_id); // For any methods that use a default implementation, add them to // the map. This is a bit unfortunate. for &method_def_id in methods.iter() { for &source in ty::method(tcx, method_def_id).provided_source.iter() { tcx.provided_method_sources.borrow_mut().insert(method_def_id, source); } } // Store the implementation info. tcx.impl_methods.borrow_mut().insert(implementation_def_id, methods); }); tcx.populated_external_traits.borrow_mut().insert(trait_id); } /// Given the def_id of an impl, return the def_id of the trait it implements. /// If it implements no trait, return `None`. pub fn trait_id_of_impl(tcx: &ctxt, def_id: ast::DefId) -> Option { let node = match tcx.map.find(def_id.node) { Some(node) => node, None => return None }; match node { ast_map::NodeItem(item) => { match item.node { ast::ItemImpl(_, Some(ref trait_ref), _, _) => { Some(node_id_to_trait_ref(tcx, trait_ref.ref_id).def_id) } _ => None } } _ => None } } /// If the given def ID describes a method belonging to a trait (either a /// default method or an implementation of a trait method), return the ID of /// the trait that the method belongs to. Otherwise, return `None`. pub fn trait_of_method(tcx: &ctxt, def_id: ast::DefId) -> Option { if def_id.krate != LOCAL_CRATE { return csearch::get_trait_of_method(&tcx.sess.cstore, def_id, tcx); } match tcx.methods.borrow().find_copy(&def_id) { Some(method) => { match method.container { TraitContainer(def_id) => Some(def_id), ImplContainer(def_id) => trait_id_of_impl(tcx, def_id), } } None => None } } /// If the given def ID describes a method belonging to a trait, (either a /// default method or an implementation of a trait method), return the ID of /// the method inside trait definition (this means that if the given def ID /// is already that of the original trait method, then the return value is /// the same). /// Otherwise, return `None`. pub fn trait_method_of_method(tcx: &ctxt, def_id: ast::DefId) -> Option { let method = match tcx.methods.borrow().find(&def_id) { Some(m) => m.clone(), None => return None, }; let name = method.ident.name; match trait_of_method(tcx, def_id) { Some(trait_did) => { let trait_methods = ty::trait_methods(tcx, trait_did); trait_methods.iter() .position(|m| m.ident.name == name) .map(|idx| ty::trait_method(tcx, trait_did, idx).def_id) } None => None } } /// Creates a hash of the type `t` which will be the same no matter what crate /// context it's calculated within. This is used by the `type_id` intrinsic. pub fn hash_crate_independent(tcx: &ctxt, t: t, svh: &Svh) -> u64 { let mut state = sip::SipState::new(); macro_rules! byte( ($b:expr) => { ($b as u8).hash(&mut state) } ); macro_rules! hash( ($e:expr) => { $e.hash(&mut state) } ); let region = |_state: &mut sip::SipState, r: Region| { match r { ReStatic => {} ReEmpty | ReEarlyBound(..) | ReLateBound(..) | ReFree(..) | ReScope(..) | ReInfer(..) => { tcx.sess.bug("non-static region found when hashing a type") } } }; let did = |state: &mut sip::SipState, did: DefId| { let h = if ast_util::is_local(did) { svh.clone() } else { tcx.sess.cstore.get_crate_hash(did.krate) }; h.as_str().hash(state); did.node.hash(state); }; let mt = |state: &mut sip::SipState, mt: mt| { mt.mutbl.hash(state); }; ty::walk_ty(t, |t| { match ty::get(t).sty { ty_nil => byte!(0), ty_bot => byte!(1), ty_bool => byte!(2), ty_char => byte!(3), ty_int(i) => { byte!(4); hash!(i); } ty_uint(u) => { byte!(5); hash!(u); } ty_float(f) => { byte!(6); hash!(f); } ty_str => { byte!(7); } ty_enum(d, _) => { byte!(8); did(&mut state, d); } ty_box(_) => { byte!(9); } ty_uniq(_) => { byte!(10); } ty_vec(m, Some(_)) => { byte!(11); mt(&mut state, m); 1u8.hash(&mut state); } ty_vec(m, None) => { byte!(11); mt(&mut state, m); 0u8.hash(&mut state); } ty_ptr(m) => { byte!(12); mt(&mut state, m); } ty_rptr(r, m) => { byte!(13); region(&mut state, r); mt(&mut state, m); } ty_bare_fn(ref b) => { byte!(14); hash!(b.fn_style); hash!(b.abi); } ty_closure(ref c) => { byte!(15); hash!(c.fn_style); hash!(c.onceness); hash!(c.bounds); match c.store { UniqTraitStore => byte!(0), RegionTraitStore(r, m) => { byte!(1) region(&mut state, r); assert_eq!(m, ast::MutMutable); } } } ty_trait(box ty::TyTrait { def_id: d, store, bounds, .. }) => { byte!(17); did(&mut state, d); match store { UniqTraitStore => byte!(0), RegionTraitStore(r, m) => { byte!(1) region(&mut state, r); hash!(m); } } hash!(bounds); } ty_struct(d, _) => { byte!(18); did(&mut state, d); } ty_tup(ref inner) => { byte!(19); hash!(inner.len()); } ty_param(p) => { byte!(20); hash!(p.idx); did(&mut state, p.def_id); } ty_self(d) => { byte!(21); did(&mut state, d); } ty_infer(_) => unreachable!(), ty_err => byte!(23), } }); state.result() } impl Variance { pub fn to_str(self) -> &'static str { match self { Covariant => "+", Contravariant => "-", Invariant => "o", Bivariant => "*", } } } pub fn construct_parameter_environment( tcx: &ctxt, self_bound: Option>, item_type_params: &[TypeParameterDef], method_type_params: &[TypeParameterDef], item_region_params: &[RegionParameterDef], method_region_params: &[RegionParameterDef], free_id: ast::NodeId) -> ParameterEnvironment { /*! See `ParameterEnvironment` struct def'n for details */ // // Construct the free substs. // // map Self => Self let self_ty = self_bound.as_ref().map(|t| ty::mk_self(tcx, t.def_id)); // map A => A let num_item_type_params = item_type_params.len(); let num_method_type_params = method_type_params.len(); let num_type_params = num_item_type_params + num_method_type_params; let type_params = Vec::from_fn(num_type_params, |i| { let def_id = if i < num_item_type_params { item_type_params[i].def_id } else { method_type_params[i - num_item_type_params].def_id }; ty::mk_param(tcx, i, def_id) }); // map bound 'a => free 'a let region_params = { fn push_region_params(mut accum: Vec, free_id: ast::NodeId, region_params: &[RegionParameterDef]) -> Vec { for r in region_params.iter() { accum.push( ty::ReFree(ty::FreeRegion { scope_id: free_id, bound_region: ty::BrNamed(r.def_id, r.name)})); } accum } let t = push_region_params(vec!(), free_id, item_region_params); push_region_params(t, free_id, method_region_params) }; let free_substs = substs { self_ty: self_ty, tps: type_params, regions: ty::NonerasedRegions(OwnedSlice::from_vec(region_params)) }; // // Compute the bounds on Self and the type parameters. // let self_bound_substd = self_bound.map(|b| b.subst(tcx, &free_substs)); let type_param_bounds_substd = Vec::from_fn(num_type_params, |i| { if i < num_item_type_params { (*item_type_params[i].bounds).subst(tcx, &free_substs) } else { let j = i - num_item_type_params; (*method_type_params[j].bounds).subst(tcx, &free_substs) } }); debug!("construct_parameter_environment: free_id={} \ free_subst={} \ self_param_bound={} \ type_param_bound={}", free_id, free_substs.repr(tcx), self_bound_substd.repr(tcx), type_param_bounds_substd.repr(tcx)); ty::ParameterEnvironment { free_substs: free_substs, self_param_bound: self_bound_substd, type_param_bounds: type_param_bounds_substd, } } impl substs { pub fn empty() -> substs { substs { self_ty: None, tps: Vec::new(), regions: NonerasedRegions(OwnedSlice::empty()) } } } impl BorrowKind { pub fn from_mutbl(m: ast::Mutability) -> BorrowKind { match m { ast::MutMutable => MutBorrow, ast::MutImmutable => ImmBorrow, } } pub fn to_user_str(&self) -> &'static str { match *self { MutBorrow => "mutable", ImmBorrow => "immutable", UniqueImmBorrow => "uniquely immutable", } } } impl mc::Typer for ty::ctxt { fn tcx<'a>(&'a self) -> &'a ty::ctxt { self } fn node_ty(&self, id: ast::NodeId) -> mc::McResult { Ok(ty::node_id_to_type(self, id)) } fn node_method_ty(&self, method_call: typeck::MethodCall) -> Option { self.method_map.borrow().find(&method_call).map(|method| method.ty) } fn adjustments<'a>(&'a self) -> &'a RefCell> { &self.adjustments } fn is_method_call(&self, id: ast::NodeId) -> bool { self.method_map.borrow().contains_key(&typeck::MethodCall::expr(id)) } fn temporary_scope(&self, rvalue_id: ast::NodeId) -> Option { self.region_maps.temporary_scope(rvalue_id) } fn upvar_borrow(&self, upvar_id: ty::UpvarId) -> ty::UpvarBorrow { self.upvar_borrow_map.borrow().get_copy(&upvar_id) } }