rust/src/librustc/middle/ty.rs
2013-07-12 16:13:51 -04:00

4379 lines
136 KiB
Rust

// Copyright 2012-2013 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 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use driver::session;
use metadata::csearch;
use metadata;
use middle::const_eval;
use middle::freevars;
use middle::resolve::{Impl, MethodInfo};
use middle::resolve;
use middle::ty;
use middle::subst::Subst;
use middle::typeck;
use middle;
use util::ppaux::{note_and_explain_region, bound_region_ptr_to_str};
use util::ppaux::{trait_store_to_str, ty_to_str, vstore_to_str};
use util::ppaux::{Repr, UserString};
use util::common::{indenter};
use util::enum_set::{EnumSet, CLike};
use std::cast;
use std::cmp;
use std::hashmap::{HashMap, HashSet};
use std::ops;
use std::ptr::to_unsafe_ptr;
use std::to_bytes;
use std::u32;
use std::uint;
use std::vec;
use syntax::ast::*;
use syntax::ast_util::is_local;
use syntax::ast_util;
use syntax::attr;
use syntax::codemap::span;
use syntax::codemap;
use syntax::parse::token;
use syntax::{ast, ast_map};
use syntax::opt_vec::OptVec;
use syntax::opt_vec;
use syntax::abi::AbiSet;
use syntax;
// Data types
#[deriving(Eq, IterBytes)]
pub struct field {
ident: ast::ident,
mt: mt
}
pub struct Method {
ident: ast::ident,
generics: ty::Generics,
transformed_self_ty: Option<ty::t>,
fty: BareFnTy,
explicit_self: ast::explicit_self_,
vis: ast::visibility,
def_id: ast::def_id
}
impl Method {
pub fn new(ident: ast::ident,
generics: ty::Generics,
transformed_self_ty: Option<ty::t>,
fty: BareFnTy,
explicit_self: ast::explicit_self_,
vis: ast::visibility,
def_id: ast::def_id)
-> Method {
// Check the invariants.
if explicit_self == ast::sty_static {
assert!(transformed_self_ty.is_none());
} else {
assert!(transformed_self_ty.is_some());
}
Method {
ident: ident,
generics: generics,
transformed_self_ty: transformed_self_ty,
fty: fty,
explicit_self: explicit_self,
vis: vis,
def_id: def_id
}
}
}
#[deriving(Eq, IterBytes)]
pub struct mt {
ty: t,
mutbl: ast::mutability,
}
#[deriving(Eq, Encodable, Decodable, IterBytes)]
pub enum vstore {
vstore_fixed(uint),
vstore_uniq,
vstore_box,
vstore_slice(Region)
}
#[deriving(Eq, IterBytes, Encodable, Decodable)]
pub enum TraitStore {
BoxTraitStore, // @Trait
UniqTraitStore, // ~Trait
RegionTraitStore(Region), // &Trait
}
// XXX: This should probably go away at some point. Maybe after destructors
// do?
#[deriving(Eq, Encodable, Decodable)]
pub enum SelfMode {
ByCopy,
ByRef,
}
pub struct field_ty {
ident: ident,
id: def_id,
vis: ast::visibility,
}
// Contains information needed to resolve types and (in the future) look up
// the types of AST nodes.
#[deriving(Eq,IterBytes)]
pub struct creader_cache_key {
cnum: int,
pos: uint,
len: uint
}
type creader_cache = @mut HashMap<creader_cache_key, t>;
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)
}
}
// NB: Do not replace this with #[deriving(IterBytes)], as above. (Figured
// this out the hard way.)
impl to_bytes::IterBytes for intern_key {
fn iter_bytes(&self, lsb0: bool, f: to_bytes::Cb) -> bool {
unsafe {
(*self.sty).iter_bytes(lsb0, f)
}
}
}
pub enum ast_ty_to_ty_cache_entry {
atttce_unresolved, /* not resolved yet */
atttce_resolved(t) /* resolved to a type, irrespective of region */
}
pub type opt_region_variance = Option<region_variance>;
#[deriving(Eq, Decodable, Encodable)]
pub enum region_variance { rv_covariant, rv_invariant, rv_contravariant }
#[deriving(Decodable, Encodable)]
pub enum AutoAdjustment {
AutoAddEnv(ty::Region, ast::Sigil),
AutoDerefRef(AutoDerefRef)
}
#[deriving(Decodable, Encodable)]
pub struct AutoDerefRef {
autoderefs: uint,
autoref: Option<AutoRef>
}
#[deriving(Decodable, Encodable)]
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 @fn()/~fn()/&fn() to &fn()
AutoBorrowFn(Region),
/// Convert from T to *T
AutoUnsafe(ast::mutability)
}
// Stores information about provided methods (a.k.a. default methods) in
// implementations.
//
// This is a map from ID of each implementation to the method info and trait
// method ID of each of the default methods belonging to the trait that
// implementation implements.
pub type ProvidedMethodsMap = @mut HashMap<def_id,@mut ~[@ProvidedMethodInfo]>;
// Stores the method info and definition ID of the associated trait method for
// each instantiation of each provided method.
pub struct ProvidedMethodInfo {
method_info: @MethodInfo,
trait_method_def_id: def_id
}
pub struct ProvidedMethodSource {
method_id: ast::def_id,
impl_id: ast::def_id
}
pub type ctxt = @ctxt_;
struct ctxt_ {
diag: @syntax::diagnostic::span_handler,
interner: @mut HashMap<intern_key, ~t_box_>,
next_id: @mut uint,
cstore: @mut metadata::cstore::CStore,
sess: session::Session,
def_map: resolve::DefMap,
region_maps: @mut middle::region::RegionMaps,
region_paramd_items: middle::region::region_paramd_items,
// 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.
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.
node_type_substs: @mut HashMap<node_id, ~[t]>,
// Maps from a method to the method "descriptor"
methods: @mut HashMap<def_id, @Method>,
// Maps from a trait def-id to a list of the def-ids of its methods
trait_method_def_ids: @mut HashMap<def_id, @~[def_id]>,
// A cache for the trait_methods() routine
trait_methods_cache: @mut HashMap<def_id, @~[@Method]>,
impl_trait_cache: @mut HashMap<ast::def_id, Option<@ty::TraitRef>>,
trait_refs: @mut HashMap<node_id, @TraitRef>,
trait_defs: @mut HashMap<def_id, @TraitDef>,
items: ast_map::map,
intrinsic_defs: @mut HashMap<ast::def_id, t>,
freevars: freevars::freevar_map,
tcache: type_cache,
rcache: creader_cache,
ccache: constness_cache,
short_names_cache: @mut HashMap<t, @str>,
needs_unwind_cleanup_cache: @mut HashMap<t, bool>,
tc_cache: @mut HashMap<uint, TypeContents>,
ast_ty_to_ty_cache: @mut HashMap<node_id, ast_ty_to_ty_cache_entry>,
enum_var_cache: @mut HashMap<def_id, @~[VariantInfo]>,
ty_param_defs: @mut HashMap<ast::node_id, TypeParameterDef>,
adjustments: @mut HashMap<ast::node_id, @AutoAdjustment>,
normalized_cache: @mut HashMap<t, t>,
lang_items: middle::lang_items::LanguageItems,
// A mapping from an implementation ID to the method info and trait
// method ID of the provided (a.k.a. default) methods in the traits that
// that implementation implements.
provided_methods: ProvidedMethodsMap,
provided_method_sources: @mut HashMap<ast::def_id, ProvidedMethodSource>,
supertraits: @mut HashMap<ast::def_id, @~[@TraitRef]>,
// 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.
destructor_for_type: @mut HashMap<ast::def_id, ast::def_id>,
// A method will be in this list if and only if it is a destructor.
destructors: @mut HashSet<ast::def_id>,
// Maps a trait onto a mapping from self-ty to impl
trait_impls: @mut HashMap<ast::def_id, @mut HashMap<t, @Impl>>,
// Maps a base type to its impl
base_impls: @mut HashMap<ast::def_id, @mut ~[@Impl]>,
// Set of used unsafe nodes (functions or blocks). Unsafe nodes not
// present in this set can be warned about.
used_unsafe: @mut HashSet<ast::node_id>,
// 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.
used_mut_nodes: @mut HashSet<ast::node_id>,
}
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-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_ {
sty: sty,
id: uint,
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 {}
pub type t = *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_has_regions(t: t) -> bool {
tbox_has_flag(get(t), has_regions)
}
pub fn type_id(t: t) -> uint { get(t).id }
#[deriving(Eq,IterBytes)]
pub struct BareFnTy {
purity: ast::purity,
abis: AbiSet,
sig: FnSig
}
#[deriving(Eq,IterBytes)]
pub struct ClosureTy {
purity: ast::purity,
sigil: ast::Sigil,
onceness: ast::Onceness,
region: Region,
bounds: BuiltinBounds,
sig: FnSig,
}
/**
* Signature of a function type, which I have arbitrarily
* decided to use to refer to the input/output types.
*
* - `lifetimes` is the list of region names bound in this fn.
* - `inputs` is the list of arguments and their modes.
* - `output` is the return type. */
#[deriving(Eq, IterBytes)]
pub struct FnSig {
bound_lifetime_names: OptVec<ast::ident>,
inputs: ~[t],
output: t
}
#[deriving(Eq, IterBytes)]
pub struct param_ty {
idx: uint,
def_id: def_id
}
/// Representation of regions:
#[deriving(Eq, IterBytes, Encodable, Decodable)]
pub enum Region {
/// Bound regions are found (primarily) in function types. They indicate
/// region parameters that have yet to be replaced with actual regions
/// (analogous to type parameters, except that due to the monomorphic
/// nature of our type system, bound type parameters are always replaced
/// with fresh type variables whenever an item is referenced, so type
/// parameters only appear "free" in types. Regions in contrast can
/// appear free or bound.). When a function is called, all bound regions
/// tied to that function's node-id are replaced with fresh region
/// variables whose value is then inferred.
re_bound(bound_region),
/// 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.
re_free(FreeRegion),
/// A concrete region naming some expression within the current function.
re_scope(node_id),
/// Static data that has an "infinite" lifetime. Top in the region lattice.
re_static,
/// A region variable. Should not exist after typeck.
re_infer(InferRegion),
/// Empty lifetime is for data that is never accessed.
/// Bottom in the region lattice. We treat re_empty 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 re_empty is to have a region
/// variable with no constraints.
re_empty,
}
impl Region {
pub fn is_bound(&self) -> bool {
match self {
&re_bound(*) => true,
_ => false
}
}
}
#[deriving(Eq, IterBytes, Encodable, Decodable)]
pub struct FreeRegion {
scope_id: node_id,
bound_region: bound_region
}
#[deriving(Eq, IterBytes, Encodable, Decodable)]
pub enum bound_region {
/// The self region for structs, impls (&T in a type defn or &'self T)
br_self,
/// An anonymous region parameter for a given fn (&T)
br_anon(uint),
/// Named region parameters for functions (a in &'a T)
br_named(ast::ident),
/// Fresh bound identifiers created during GLB computations.
br_fresh(uint),
/**
* Handles capture-avoiding substitution in a rather subtle case. If you
* have a closure whose argument types are being inferred based on the
* expected type, and the expected type includes bound regions, then we
* will wrap those bound regions in a br_cap_avoid() with the id of the
* fn expression. This ensures that the names are not "captured" by the
* enclosing scope, which may define the same names. For an example of
* where this comes up, see src/test/compile-fail/regions-ret-borrowed.rs
* and regions-ret-borrowed-1.rs. */
br_cap_avoid(ast::node_id, @bound_region),
}
type opt_region = Option<Region>;
/**
* 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(Eq, IterBytes)]
pub struct substs {
self_r: opt_region,
self_ty: Option<ty::t>,
tps: ~[t]
}
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_INT, super::ty_int(ast::ty_i), 2)
def_prim_ty!(TY_CHAR, super::ty_int(ast::ty_char), 3)
def_prim_ty!(TY_I8, super::ty_int(ast::ty_i8), 4)
def_prim_ty!(TY_I16, super::ty_int(ast::ty_i16), 5)
def_prim_ty!(TY_I32, super::ty_int(ast::ty_i32), 6)
def_prim_ty!(TY_I64, super::ty_int(ast::ty_i64), 7)
def_prim_ty!(TY_UINT, super::ty_uint(ast::ty_u), 8)
def_prim_ty!(TY_U8, super::ty_uint(ast::ty_u8), 9)
def_prim_ty!(TY_U16, super::ty_uint(ast::ty_u16), 10)
def_prim_ty!(TY_U32, super::ty_uint(ast::ty_u32), 11)
def_prim_ty!(TY_U64, super::ty_uint(ast::ty_u64), 12)
def_prim_ty!(TY_FLOAT, super::ty_float(ast::ty_f), 13)
def_prim_ty!(TY_F32, super::ty_float(ast::ty_f32), 14)
def_prim_ty!(TY_F64, super::ty_float(ast::ty_f64), 15)
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(Eq, IterBytes)]
pub enum sty {
ty_nil,
ty_bot,
ty_bool,
ty_int(ast::int_ty),
ty_uint(ast::uint_ty),
ty_float(ast::float_ty),
ty_estr(vstore),
ty_enum(def_id, substs),
ty_box(mt),
ty_uniq(mt),
ty_evec(mt, vstore),
ty_ptr(mt),
ty_rptr(Region, mt),
ty_bare_fn(BareFnTy),
ty_closure(ClosureTy),
ty_trait(def_id, substs, TraitStore, ast::mutability, BuiltinBounds),
ty_struct(def_id, substs),
ty_tup(~[t]),
ty_param(param_ty), // type parameter
ty_self(def_id), /* 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)
// "Fake" types, used for trans purposes
ty_type, // type_desc*
ty_opaque_box, // used by monomorphizer to represent any @ box
ty_opaque_closure_ptr(Sigil), // ptr to env for &fn, @fn, ~fn
ty_unboxed_vec(mt),
}
#[deriving(Eq, IterBytes)]
pub struct TraitRef {
def_id: def_id,
substs: substs
}
#[deriving(Eq)]
pub enum IntVarValue {
IntType(ast::int_ty),
UintType(ast::uint_ty),
}
pub enum terr_vstore_kind {
terr_vec, terr_str, terr_fn, terr_trait
}
pub struct expected_found<T> {
expected: T,
found: T
}
// Data structures used in type unification
pub enum type_err {
terr_mismatch,
terr_purity_mismatch(expected_found<purity>),
terr_onceness_mismatch(expected_found<Onceness>),
terr_abi_mismatch(expected_found<AbiSet>),
terr_mutability,
terr_sigil_mismatch(expected_found<ast::Sigil>),
terr_box_mutability,
terr_ptr_mutability,
terr_ref_mutability,
terr_vec_mutability,
terr_tuple_size(expected_found<uint>),
terr_ty_param_size(expected_found<uint>),
terr_record_size(expected_found<uint>),
terr_record_mutability,
terr_record_fields(expected_found<ident>),
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(bound_region, Region),
terr_regions_overly_polymorphic(bound_region, Region),
terr_vstores_differ(terr_vstore_kind, expected_found<vstore>),
terr_trait_stores_differ(terr_vstore_kind, expected_found<TraitStore>),
terr_in_field(@type_err, ast::ident),
terr_sorts(expected_found<t>),
terr_integer_as_char,
terr_int_mismatch(expected_found<IntVarValue>),
terr_float_mismatch(expected_found<ast::float_ty>),
terr_traits(expected_found<ast::def_id>),
terr_builtin_bounds(expected_found<BuiltinBounds>),
}
#[deriving(Eq, IterBytes)]
pub struct ParamBounds {
builtin_bounds: BuiltinBounds,
trait_bounds: ~[@TraitRef]
}
pub type BuiltinBounds = EnumSet<BuiltinBound>;
#[deriving(Eq, IterBytes)]
pub enum BuiltinBound {
BoundCopy,
BoundStatic,
BoundSend,
BoundFreeze,
BoundSized,
}
pub fn EmptyBuiltinBounds() -> BuiltinBounds {
EnumSet::empty()
}
pub fn AllBuiltinBounds() -> BuiltinBounds {
let mut set = EnumSet::empty();
set.add(BoundCopy);
set.add(BoundStatic);
set.add(BoundSend);
set.add(BoundFreeze);
set.add(BoundSized);
set
}
impl CLike for BuiltinBound {
pub fn to_uint(&self) -> uint {
*self as uint
}
pub fn from_uint(v: uint) -> BuiltinBound {
unsafe { cast::transmute(v) }
}
}
#[deriving(Eq, IterBytes)]
pub struct TyVid(uint);
#[deriving(Eq, IterBytes)]
pub struct IntVid(uint);
#[deriving(Eq, IterBytes)]
pub struct FloatVid(uint);
#[deriving(Eq, Encodable, Decodable, IterBytes)]
pub struct RegionVid {
id: uint
}
#[deriving(Eq, IterBytes)]
pub enum InferTy {
TyVar(TyVid),
IntVar(IntVid),
FloatVar(FloatVid)
}
#[deriving(Encodable, Decodable, IterBytes)]
pub enum InferRegion {
ReVar(RegionVid),
ReSkolemized(uint, bound_region)
}
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 { **self }
}
impl ToStr for TyVid {
fn to_str(&self) -> ~str { fmt!("<V%u>", self.to_uint()) }
}
impl Vid for IntVid {
fn to_uint(&self) -> uint { **self }
}
impl ToStr for IntVid {
fn to_str(&self) -> ~str { fmt!("<VI%u>", self.to_uint()) }
}
impl Vid for FloatVid {
fn to_uint(&self) -> uint { **self }
}
impl ToStr for FloatVid {
fn to_str(&self) -> ~str { fmt!("<VF%u>", self.to_uint()) }
}
impl Vid for RegionVid {
fn to_uint(&self) -> uint { self.id }
}
impl ToStr for RegionVid {
fn to_str(&self) -> ~str { fmt!("%?", self.id) }
}
impl ToStr for FnSig {
fn to_str(&self) -> ~str {
// grr, without tcx not much we can do.
return ~"(...)";
}
}
impl ToStr for InferTy {
fn to_str(&self) -> ~str {
match *self {
TyVar(ref v) => v.to_str(),
IntVar(ref v) => v.to_str(),
FloatVar(ref v) => v.to_str()
}
}
}
impl ToStr for IntVarValue {
fn to_str(&self) -> ~str {
match *self {
IntType(ref v) => v.to_str(),
UintType(ref v) => v.to_str(),
}
}
}
pub struct TypeParameterDef {
ident: ast::ident,
def_id: ast::def_id,
bounds: @ParamBounds
}
/// Information about the type/lifetime parametesr associated with an item.
/// Analogous to ast::Generics.
pub struct Generics {
type_param_defs: @~[TypeParameterDef],
region_param: Option<region_variance>,
}
impl Generics {
pub fn has_type_params(&self) -> bool {
!self.type_param_defs.is_empty()
}
}
/// 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
pub struct ty_param_bounds_and_ty {
generics: Generics,
ty: t
}
/// As `ty_param_bounds_and_ty` but for a trait ref.
pub struct TraitDef {
generics: Generics,
trait_ref: @ty::TraitRef,
}
pub struct ty_param_substs_and_ty {
substs: ty::substs,
ty: ty::t
}
type type_cache = @mut HashMap<ast::def_id, ty_param_bounds_and_ty>;
type constness_cache = @mut HashMap<ast::def_id, const_eval::constness>;
pub type node_type_table = @mut HashMap<uint,t>;
fn mk_rcache() -> creader_cache {
return @mut HashMap::new();
}
pub fn new_ty_hash<V:Copy>() -> @mut HashMap<t, V> {
@mut HashMap::new()
}
pub fn mk_ctxt(s: session::Session,
dm: resolve::DefMap,
amap: ast_map::map,
freevars: freevars::freevar_map,
region_maps: @mut middle::region::RegionMaps,
region_paramd_items: middle::region::region_paramd_items,
lang_items: middle::lang_items::LanguageItems)
-> ctxt {
@ctxt_ {
diag: s.diagnostic(),
interner: @mut HashMap::new(),
next_id: @mut primitives::LAST_PRIMITIVE_ID,
cstore: s.cstore,
sess: s,
def_map: dm,
region_maps: region_maps,
region_paramd_items: region_paramd_items,
node_types: @mut HashMap::new(),
node_type_substs: @mut HashMap::new(),
trait_refs: @mut HashMap::new(),
trait_defs: @mut HashMap::new(),
items: amap,
intrinsic_defs: @mut HashMap::new(),
freevars: freevars,
tcache: @mut HashMap::new(),
rcache: mk_rcache(),
ccache: @mut HashMap::new(),
short_names_cache: new_ty_hash(),
needs_unwind_cleanup_cache: new_ty_hash(),
tc_cache: @mut HashMap::new(),
ast_ty_to_ty_cache: @mut HashMap::new(),
enum_var_cache: @mut HashMap::new(),
methods: @mut HashMap::new(),
trait_method_def_ids: @mut HashMap::new(),
trait_methods_cache: @mut HashMap::new(),
impl_trait_cache: @mut HashMap::new(),
ty_param_defs: @mut HashMap::new(),
adjustments: @mut HashMap::new(),
normalized_cache: new_ty_hash(),
lang_items: lang_items,
provided_methods: @mut HashMap::new(),
provided_method_sources: @mut HashMap::new(),
supertraits: @mut HashMap::new(),
destructor_for_type: @mut HashMap::new(),
destructors: @mut HashSet::new(),
trait_impls: @mut HashMap::new(),
base_impls: @mut HashMap::new(),
used_unsafe: @mut HashSet::new(),
used_mut_nodes: @mut HashSet::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).
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),
_ => {}
};
let key = intern_key { sty: to_unsafe_ptr(&st) };
match cx.interner.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::re_infer(_) => needs_infer as uint,
_ => 0u
}
}
}
fn sflags(substs: &substs) -> uint {
let mut f = 0u;
for substs.tps.iter().advance |tt| { f |= get(*tt).flags; }
for substs.self_r.iter().advance |r| { f |= rflags(*r) }
return f;
}
match &st {
&ty_estr(vstore_slice(r)) => {
flags |= rflags(r);
}
&ty_evec(ref mt, vstore_slice(r)) => {
flags |= rflags(r);
flags |= get(mt.ty).flags;
}
&ty_nil | &ty_bool | &ty_int(_) | &ty_float(_) | &ty_uint(_) |
&ty_estr(_) | &ty_type | &ty_opaque_closure_ptr(_) |
&ty_opaque_box => (),
// 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) |
&ty_trait(_, ref substs, _, _, _) => {
flags |= sflags(substs);
}
&ty_box(ref m) | &ty_uniq(ref m) | &ty_evec(ref m, _) |
&ty_ptr(ref m) | &ty_unboxed_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 ts.iter().advance |tt| { flags |= get(*tt).flags; },
&ty_bare_fn(ref f) => {
for f.sig.inputs.iter().advance |a| { flags |= get(*a).flags; }
flags |= get(f.sig.output).flags;
// T -> _|_ is *not* _|_ !
flags &= !(has_ty_bot as uint);
}
&ty_closure(ref f) => {
flags |= rflags(f.region);
for f.sig.inputs.iter().advance |a| { flags |= get(*a).flags; }
flags |= get(f.sig.output).flags;
// T -> _|_ is *not* _|_ !
flags &= !(has_ty_bot as uint);
}
}
let t = ~t_box_ {
sty: st,
id: *cx.next_id,
flags: flags,
};
let sty_ptr = to_unsafe_ptr(&t.sty);
let key = intern_key {
sty: sty_ptr,
};
cx.interner.insert(key, t);
*cx.next_id += 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_float() -> t { mk_prim_t(&primitives::TY_FLOAT) }
#[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_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::int_ty) -> t {
match tm {
ast::ty_i => mk_int(),
ast::ty_char => mk_char(),
ast::ty_i8 => mk_i8(),
ast::ty_i16 => mk_i16(),
ast::ty_i32 => mk_i32(),
ast::ty_i64 => mk_i64(),
}
}
pub fn mk_mach_uint(tm: ast::uint_ty) -> t {
match tm {
ast::ty_u => mk_uint(),
ast::ty_u8 => mk_u8(),
ast::ty_u16 => mk_u16(),
ast::ty_u32 => mk_u32(),
ast::ty_u64 => mk_u64(),
}
}
pub fn mk_mach_float(tm: ast::float_ty) -> t {
match tm {
ast::ty_f => mk_float(),
ast::ty_f32 => mk_f32(),
ast::ty_f64 => mk_f64(),
}
}
#[inline]
pub fn mk_char() -> t { mk_prim_t(&primitives::TY_CHAR) }
pub fn mk_estr(cx: ctxt, t: vstore) -> t {
mk_t(cx, ty_estr(t))
}
pub fn mk_enum(cx: ctxt, did: ast::def_id, 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, tm: mt) -> t { mk_t(cx, ty_box(tm)) }
pub fn mk_imm_box(cx: ctxt, ty: t) -> t {
mk_box(cx, mt {ty: ty, mutbl: ast::m_imm})
}
pub fn mk_uniq(cx: ctxt, tm: mt) -> t { mk_t(cx, ty_uniq(tm)) }
pub fn mk_imm_uniq(cx: ctxt, ty: t) -> t {
mk_uniq(cx, mt {ty: ty, mutbl: ast::m_imm})
}
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::m_mutbl})
}
pub fn mk_imm_rptr(cx: ctxt, r: Region, ty: t) -> t {
mk_rptr(cx, r, mt {ty: ty, mutbl: ast::m_imm})
}
pub fn mk_mut_ptr(cx: ctxt, ty: t) -> t {
mk_ptr(cx, mt {ty: ty, mutbl: ast::m_mutbl})
}
pub fn mk_imm_ptr(cx: ctxt, ty: t) -> t {
mk_ptr(cx, mt {ty: ty, mutbl: ast::m_imm})
}
pub fn mk_nil_ptr(cx: ctxt) -> t {
mk_ptr(cx, mt {ty: mk_nil(), mutbl: ast::m_imm})
}
pub fn mk_evec(cx: ctxt, tm: mt, t: vstore) -> t {
mk_t(cx, ty_evec(tm, t))
}
pub fn mk_unboxed_vec(cx: ctxt, tm: mt) -> t {
mk_t(cx, ty_unboxed_vec(tm))
}
pub fn mk_mut_unboxed_vec(cx: ctxt, ty: t) -> t {
mk_t(cx, ty_unboxed_vec(mt {ty: ty, mutbl: ast::m_imm}))
}
pub fn mk_tup(cx: ctxt, ts: ~[t]) -> t { mk_t(cx, ty_tup(ts)) }
pub fn mk_closure(cx: ctxt, fty: ClosureTy) -> t {
mk_t(cx, ty_closure(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, input_tys: &[ty::t], output: ty::t) -> t {
let input_args = input_tys.map(|t| *t);
mk_bare_fn(cx,
BareFnTy {
purity: ast::impure_fn,
abis: AbiSet::Rust(),
sig: FnSig {
bound_lifetime_names: opt_vec::Empty,
inputs: input_args,
output: output
}
})
}
pub fn mk_trait(cx: ctxt,
did: ast::def_id,
substs: substs,
store: TraitStore,
mutability: ast::mutability,
bounds: BuiltinBounds)
-> t {
// take a copy of substs so that we own the vectors inside
mk_t(cx, ty_trait(did, substs, store, mutability, bounds))
}
pub fn mk_struct(cx: ctxt, struct_id: ast::def_id, 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::def_id) -> t { mk_t(cx, ty_self(did)) }
pub fn mk_param(cx: ctxt, n: uint, k: def_id) -> t {
mk_t(cx, ty_param(param_ty { idx: n, def_id: k }))
}
pub fn mk_type(cx: ctxt) -> t { mk_t(cx, ty_type) }
pub fn mk_opaque_closure_ptr(cx: ctxt, sigil: ast::Sigil) -> t {
mk_t(cx, ty_opaque_closure_ptr(sigil))
}
pub fn mk_opaque_box(cx: ctxt) -> t { mk_t(cx, ty_opaque_box) }
pub fn walk_ty(ty: t, f: &fn(t)) {
maybe_walk_ty(ty, |t| { f(t); true });
}
pub fn maybe_walk_ty(ty: t, f: &fn(t) -> bool) {
if !f(ty) {
return;
}
match get(ty).sty {
ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
ty_estr(_) | ty_type | ty_opaque_box | ty_self(_) |
ty_opaque_closure_ptr(_) | ty_infer(_) | ty_param(_) | ty_err => {
}
ty_box(ref tm) | ty_evec(ref tm, _) | ty_unboxed_vec(ref tm) |
ty_ptr(ref tm) | ty_rptr(_, ref tm) | ty_uniq(ref tm) => {
maybe_walk_ty(tm.ty, f);
}
ty_enum(_, ref substs) | ty_struct(_, ref substs) |
ty_trait(_, ref substs, _, _, _) => {
for (*substs).tps.iter().advance |subty| { maybe_walk_ty(*subty, |x| f(x)); }
}
ty_tup(ref ts) => { for ts.iter().advance |tt| { maybe_walk_ty(*tt, |x| f(x)); } }
ty_bare_fn(ref ft) => {
for ft.sig.inputs.iter().advance |a| { maybe_walk_ty(*a, |x| f(x)); }
maybe_walk_ty(ft.sig.output, f);
}
ty_closure(ref ft) => {
for ft.sig.inputs.iter().advance |a| { maybe_walk_ty(*a, |x| f(x)); }
maybe_walk_ty(ft.sig.output, f);
}
}
}
pub fn fold_sty_to_ty(tcx: ty::ctxt, sty: &sty, foldop: &fn(t) -> t) -> t {
mk_t(tcx, fold_sty(sty, foldop))
}
pub fn fold_sig(sig: &FnSig, fldop: &fn(t) -> t) -> FnSig {
let args = sig.inputs.map(|arg| fldop(*arg));
FnSig {
bound_lifetime_names: copy sig.bound_lifetime_names,
inputs: args,
output: fldop(sig.output)
}
}
pub fn fold_bare_fn_ty(fty: &BareFnTy, fldop: &fn(t) -> t) -> BareFnTy {
BareFnTy {sig: fold_sig(&fty.sig, fldop),
abis: fty.abis,
purity: fty.purity}
}
fn fold_sty(sty: &sty, fldop: &fn(t) -> t) -> sty {
fn fold_substs(substs: &substs, fldop: &fn(t) -> t) -> substs {
substs {self_r: substs.self_r,
self_ty: substs.self_ty.map(|t| fldop(*t)),
tps: substs.tps.map(|t| fldop(*t))}
}
match *sty {
ty_box(ref tm) => {
ty_box(mt {ty: fldop(tm.ty), mutbl: tm.mutbl})
}
ty_uniq(ref tm) => {
ty_uniq(mt {ty: fldop(tm.ty), mutbl: tm.mutbl})
}
ty_ptr(ref tm) => {
ty_ptr(mt {ty: fldop(tm.ty), mutbl: tm.mutbl})
}
ty_unboxed_vec(ref tm) => {
ty_unboxed_vec(mt {ty: fldop(tm.ty), mutbl: tm.mutbl})
}
ty_evec(ref tm, vst) => {
ty_evec(mt {ty: fldop(tm.ty), mutbl: tm.mutbl}, vst)
}
ty_enum(tid, ref substs) => {
ty_enum(tid, fold_substs(substs, fldop))
}
ty_trait(did, ref substs, st, mutbl, bounds) => {
ty_trait(did, fold_substs(substs, fldop), st, mutbl, bounds)
}
ty_tup(ref ts) => {
let new_ts = ts.map(|tt| fldop(*tt));
ty_tup(new_ts)
}
ty_bare_fn(ref f) => {
ty_bare_fn(fold_bare_fn_ty(f, fldop))
}
ty_closure(ref f) => {
let sig = fold_sig(&f.sig, fldop);
ty_closure(ClosureTy {sig: sig, ..copy *f})
}
ty_rptr(r, ref tm) => {
ty_rptr(r, mt {ty: fldop(tm.ty), mutbl: tm.mutbl})
}
ty_struct(did, ref substs) => {
ty_struct(did, fold_substs(substs, fldop))
}
ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
ty_estr(_) | ty_type | ty_opaque_closure_ptr(_) | ty_err |
ty_opaque_box | ty_infer(_) | ty_param(*) | ty_self(_) => {
/*bad*/copy *sty
}
}
}
// Folds types from the bottom up.
pub fn fold_ty(cx: ctxt, t0: t, fldop: &fn(t) -> t) -> t {
let sty = fold_sty(&get(t0).sty, |t| fold_ty(cx, fldop(t), |t| fldop(t)));
fldop(mk_t(cx, sty))
}
pub fn walk_regions_and_ty(
cx: ctxt,
ty: t,
walkr: &fn(r: Region),
walkt: &fn(t: t) -> bool) {
if (walkt(ty)) {
fold_regions_and_ty(
cx, ty,
|r| { walkr(r); r },
|t| { walk_regions_and_ty(cx, t, |r| walkr(r), |t| walkt(t)); t },
|t| { walk_regions_and_ty(cx, t, |r| walkr(r), |t| walkt(t)); t });
}
}
pub fn fold_regions_and_ty(
cx: ctxt,
ty: t,
fldr: &fn(r: Region) -> Region,
fldfnt: &fn(t: t) -> t,
fldt: &fn(t: t) -> t) -> t {
fn fold_substs(
substs: &substs,
fldr: &fn(r: Region) -> Region,
fldt: &fn(t: t) -> t)
-> substs {
substs {
self_r: substs.self_r.map(|r| fldr(*r)),
self_ty: substs.self_ty.map(|t| fldt(*t)),
tps: substs.tps.map(|t| fldt(*t))
}
}
let tb = ty::get(ty);
match tb.sty {
ty::ty_rptr(r, mt) => {
let m_r = fldr(r);
let m_t = fldt(mt.ty);
ty::mk_rptr(cx, m_r, mt {ty: m_t, mutbl: mt.mutbl})
}
ty_estr(vstore_slice(r)) => {
let m_r = fldr(r);
ty::mk_estr(cx, vstore_slice(m_r))
}
ty_evec(mt, vstore_slice(r)) => {
let m_r = fldr(r);
let m_t = fldt(mt.ty);
ty::mk_evec(cx, mt {ty: m_t, mutbl: mt.mutbl}, vstore_slice(m_r))
}
ty_enum(def_id, ref substs) => {
ty::mk_enum(cx, def_id, fold_substs(substs, fldr, fldt))
}
ty_struct(def_id, ref substs) => {
ty::mk_struct(cx, def_id, fold_substs(substs, fldr, fldt))
}
ty_trait(def_id, ref substs, st, mutbl, bounds) => {
let st = match st {
RegionTraitStore(region) => RegionTraitStore(fldr(region)),
st => st,
};
ty::mk_trait(cx, def_id, fold_substs(substs, fldr, fldt), st, mutbl, bounds)
}
ty_bare_fn(ref f) => {
ty::mk_bare_fn(cx, BareFnTy {sig: fold_sig(&f.sig, fldfnt),
..copy *f})
}
ty_closure(ref f) => {
ty::mk_closure(cx, ClosureTy {region: fldr(f.region),
sig: fold_sig(&f.sig, fldfnt),
..copy *f})
}
ref sty => {
fold_sty_to_ty(cx, sty, |t| fldt(t))
}
}
}
// n.b. this function is intended to eventually replace fold_region() below,
// that is why its name is so similar.
pub fn fold_regions(
cx: ctxt,
ty: t,
fldr: &fn(r: Region, in_fn: bool) -> Region) -> t {
fn do_fold(cx: ctxt, ty: t, in_fn: bool,
fldr: &fn(Region, bool) -> Region) -> t {
debug!("do_fold(ty=%s, in_fn=%b)", ty_to_str(cx, ty), in_fn);
if !type_has_regions(ty) { return ty; }
fold_regions_and_ty(
cx, ty,
|r| fldr(r, in_fn),
|t| do_fold(cx, t, true, |r,b| fldr(r,b)),
|t| do_fold(cx, t, in_fn, |r,b| fldr(r,b)))
}
do_fold(cx, ty, false, fldr)
}
// Substitute *only* type parameters. Used in trans where regions are erased.
pub fn subst_tps(cx: ctxt, tps: &[t], self_ty_opt: Option<t>, typ: t) -> t {
if tps.len() == 0u && self_ty_opt.is_none() { return typ; }
let tb = ty::get(typ);
if self_ty_opt.is_none() && !tbox_has_flag(tb, has_params) { return typ; }
match tb.sty {
ty_param(p) => tps[p.idx],
ty_self(_) => {
match self_ty_opt {
None => cx.sess.bug("ty_self unexpected here"),
Some(self_ty) => {
subst_tps(cx, tps, self_ty_opt, self_ty)
}
}
}
ref sty => {
fold_sty_to_ty(cx, sty, |t| subst_tps(cx, tps, self_ty_opt, t))
}
}
}
pub fn substs_is_noop(substs: &substs) -> bool {
substs.tps.len() == 0u &&
substs.self_r.is_none() &&
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
}
}
pub fn type_is_structural(ty: t) -> bool {
match get(ty).sty {
ty_struct(*) | ty_tup(_) | ty_enum(*) | ty_closure(_) | ty_trait(*) |
ty_evec(_, vstore_fixed(_)) | ty_estr(vstore_fixed(_)) |
ty_evec(_, vstore_slice(_)) | ty_estr(vstore_slice(_))
=> true,
_ => false
}
}
pub fn type_is_sequence(ty: t) -> bool {
match get(ty).sty {
ty_estr(_) | ty_evec(_, _) => true,
_ => false
}
}
pub fn type_is_simd(cx: ctxt, ty: t) -> bool {
match get(ty).sty {
ty_struct(did, _) => lookup_simd(cx, did),
_ => false
}
}
pub fn type_is_str(ty: t) -> bool {
match get(ty).sty {
ty_estr(_) => true,
_ => false
}
}
pub fn sequence_element_type(cx: ctxt, ty: t) -> t {
match get(ty).sty {
ty_estr(_) => return mk_mach_uint(ast::ty_u8),
ty_evec(mt, _) | ty_unboxed_vec(mt) => return mt.ty,
_ => 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[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 get_element_type(ty: t, i: uint) -> t {
match get(ty).sty {
ty_tup(ref ts) => return ts[i],
_ => fail!("get_element_type called on invalid type")
}
}
pub fn type_is_box(ty: t) -> bool {
match get(ty).sty {
ty_box(_) => return true,
_ => return false
}
}
pub fn type_is_boxed(ty: t) -> bool {
match get(ty).sty {
ty_box(_) | ty_opaque_box |
ty_evec(_, vstore_box) | ty_estr(vstore_box) => true,
_ => false
}
}
pub fn type_is_region_ptr(ty: t) -> bool {
match get(ty).sty {
ty_rptr(_, _) => true,
_ => false
}
}
pub fn type_is_slice(ty: t) -> bool {
match get(ty).sty {
ty_evec(_, vstore_slice(_)) | ty_estr(vstore_slice(_)) => true,
_ => return false
}
}
pub fn type_is_unique_box(ty: t) -> bool {
match get(ty).sty {
ty_uniq(_) => return true,
_ => return false
}
}
pub fn type_is_unsafe_ptr(ty: t) -> bool {
match get(ty).sty {
ty_ptr(_) => return true,
_ => return false
}
}
pub fn type_is_vec(ty: t) -> bool {
return match get(ty).sty {
ty_evec(_, _) | ty_unboxed_vec(_) => true,
ty_estr(_) => true,
_ => false
};
}
pub fn type_is_unique(ty: t) -> bool {
match get(ty).sty {
ty_uniq(_) |
ty_evec(_, vstore_uniq) |
ty_estr(vstore_uniq) |
ty_opaque_closure_ptr(ast::OwnedSigil) => true,
_ => return 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_int(_) | ty_float(_) | ty_uint(_) |
ty_infer(IntVar(_)) | ty_infer(FloatVar(_)) | ty_type |
ty_bare_fn(*) | ty_ptr(_) => true,
_ => false
}
}
fn type_is_newtype_immediate(cx: ctxt, ty: t) -> bool {
match get(ty).sty {
ty_struct(def_id, ref substs) => {
let fields = struct_fields(cx, def_id, substs);
fields.len() == 1 &&
fields[0].ident == token::special_idents::unnamed_field &&
type_is_immediate(cx, fields[0].mt.ty)
}
_ => false
}
}
pub fn type_is_immediate(cx: ctxt, ty: t) -> bool {
return type_is_scalar(ty) || type_is_boxed(ty) ||
type_is_unique(ty) || type_is_region_ptr(ty) ||
type_is_newtype_immediate(cx, ty);
}
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.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.insert(ty, needs_unwind_cleanup);
return needs_unwind_cleanup;
}
fn type_needs_unwind_cleanup_(cx: ctxt, ty: t,
tycache: &mut HashSet<t>,
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;
do maybe_walk_ty(ty) |ty| {
let old_encountered_box = encountered_box;
let result = match get(ty).sty {
ty_box(_) | ty_opaque_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 (*enum_variants(cx, did)).iter().advance |v| {
for v.args.iter().advance |aty| {
let t = subst(cx, substs, *aty);
needs_unwind_cleanup |=
type_needs_unwind_cleanup_(cx, t, tycache,
encountered_box);
}
}
!needs_unwind_cleanup
}
ty_uniq(_) |
ty_estr(vstore_uniq) |
ty_estr(vstore_box) |
ty_evec(_, vstore_uniq) |
ty_evec(_, vstore_box)
=> {
// 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 borrowed pointer 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 {
bits: u32
}
impl TypeContents {
pub fn meets_bounds(&self, cx: ctxt, bbs: BuiltinBounds) -> bool {
bbs.iter().all(|bb| self.meets_bound(cx, bb))
}
pub fn meets_bound(&self, cx: ctxt, bb: BuiltinBound) -> bool {
match bb {
BoundCopy => self.is_copy(cx),
BoundStatic => self.is_static(cx),
BoundFreeze => self.is_freezable(cx),
BoundSend => self.is_sendable(cx),
BoundSized => self.is_sized(cx),
}
}
pub fn intersects(&self, tc: TypeContents) -> bool {
(self.bits & tc.bits) != 0
}
pub fn is_copy(&self, cx: ctxt) -> bool {
!self.intersects(TypeContents::noncopyable(cx))
}
pub fn noncopyable(_cx: ctxt) -> TypeContents {
TC_DTOR + TC_BORROWED_MUT + TC_ONCE_CLOSURE + TC_NONCOPY_TRAIT +
TC_EMPTY_ENUM
}
pub fn is_static(&self, cx: ctxt) -> bool {
!self.intersects(TypeContents::nonstatic(cx))
}
pub fn nonstatic(_cx: ctxt) -> TypeContents {
TC_BORROWED_POINTER
}
pub fn is_sendable(&self, cx: ctxt) -> bool {
!self.intersects(TypeContents::nonsendable(cx))
}
pub fn nonsendable(_cx: ctxt) -> TypeContents {
TC_MANAGED + TC_BORROWED_POINTER + TC_NON_SENDABLE
}
pub fn contains_managed(&self) -> bool {
self.intersects(TC_MANAGED)
}
pub fn is_freezable(&self, cx: ctxt) -> bool {
!self.intersects(TypeContents::nonfreezable(cx))
}
pub fn nonfreezable(_cx: ctxt) -> TypeContents {
TC_MUTABLE
}
pub fn is_sized(&self, cx: ctxt) -> bool {
!self.intersects(TypeContents::dynamically_sized(cx))
}
pub fn dynamically_sized(_cx: ctxt) -> TypeContents {
TC_DYNAMIC_SIZE
}
pub fn moves_by_default(&self, cx: ctxt) -> bool {
self.intersects(TypeContents::nonimplicitly_copyable(cx))
}
pub fn nonimplicitly_copyable(cx: ctxt) -> TypeContents {
TypeContents::noncopyable(cx) + TC_OWNED_POINTER + TC_OWNED_VEC
}
pub fn needs_drop(&self, cx: ctxt) -> bool {
if self.intersects(TC_NONCOPY_TRAIT) {
// Currently all noncopyable existentials are 2nd-class types
// behind owned pointers. With dynamically-sized types, remove
// this assertion.
assert!(self.intersects(TC_OWNED_POINTER) ||
// (...or stack closures without a copy bound.)
self.intersects(TC_BORROWED_POINTER));
}
let tc = TC_MANAGED + TC_DTOR + TypeContents::sendable(cx);
self.intersects(tc)
}
pub fn sendable(_cx: ctxt) -> TypeContents {
//! Any kind of sendable contents.
TC_OWNED_POINTER + TC_OWNED_VEC
}
}
impl ops::Add<TypeContents,TypeContents> for TypeContents {
fn add(&self, other: &TypeContents) -> TypeContents {
TypeContents {bits: self.bits | other.bits}
}
}
impl ops::Sub<TypeContents,TypeContents> for TypeContents {
fn sub(&self, other: &TypeContents) -> TypeContents {
TypeContents {bits: self.bits & !other.bits}
}
}
impl ToStr for TypeContents {
fn to_str(&self) -> ~str {
fmt!("TypeContents(%s)", u32::to_str_radix(self.bits, 2))
}
}
/// Constant for a type containing nothing of interest.
static TC_NONE: TypeContents = TypeContents{bits: 0b0000_0000_0000};
/// Contains a borrowed value with a lifetime other than static
static TC_BORROWED_POINTER: TypeContents = TypeContents{bits: 0b0000_0000_0001};
/// Contains an owned pointer (~T) but not slice of some kind
static TC_OWNED_POINTER: TypeContents = TypeContents{bits: 0b0000_0000_0010};
/// Contains an owned vector ~[] or owned string ~str
static TC_OWNED_VEC: TypeContents = TypeContents{bits: 0b0000_0000_0100};
/// Contains a non-copyable ~fn() or a ~Trait (NOT a ~fn:Copy() or ~Trait:Copy).
static TC_NONCOPY_TRAIT: TypeContents = TypeContents{bits: 0b0000_0000_1000};
/// Type with a destructor
static TC_DTOR: TypeContents = TypeContents{bits: 0b0000_0001_0000};
/// Contains a managed value
static TC_MANAGED: TypeContents = TypeContents{bits: 0b0000_0010_0000};
/// &mut with any region
static TC_BORROWED_MUT: TypeContents = TypeContents{bits: 0b0000_0100_0000};
/// Mutable content, whether owned or by ref
static TC_MUTABLE: TypeContents = TypeContents{bits: 0b0000_1000_0000};
/// One-shot closure
static TC_ONCE_CLOSURE: TypeContents = TypeContents{bits: 0b0001_0000_0000};
/// An enum with no variants.
static TC_EMPTY_ENUM: TypeContents = TypeContents{bits: 0b0010_0000_0000};
/// Contains a type marked with `#[no_send]`
static TC_NON_SENDABLE: TypeContents = TypeContents{bits: 0b0100_0000_0000};
/// Is a bare vector, str, function, trait, etc (only relevant at top level).
static TC_DYNAMIC_SIZE: TypeContents = TypeContents{bits: 0b1000_0000_0000};
/// All possible contents.
static TC_ALL: TypeContents = TypeContents{bits: 0b1111_1111_1111};
pub fn type_is_copyable(cx: ctxt, t: ty::t) -> bool {
type_contents(cx, t).is_copy(cx)
}
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_is_freezable(cx: ctxt, t: ty::t) -> bool {
type_contents(cx, t).is_freezable(cx)
}
pub fn type_contents(cx: ctxt, ty: t) -> TypeContents {
let ty_id = type_id(ty);
match cx.tc_cache.find(&ty_id) {
Some(tc) => { return *tc; }
None => {}
}
let mut cache = HashMap::new();
let result = tc_ty(cx, ty, &mut cache);
cx.tc_cache.insert(ty_id, result);
return result;
fn tc_ty(cx: ctxt,
ty: t,
cache: &mut HashMap<uint, TypeContents>) -> 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: ~Option<List>, ... }
//
// 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_OWNED_POINTER, in this case.
//
// The problem is, as we are doing the computation, we will also
// compute an *intermediate* contents for, e.g., Option<List> 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<List> 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_OWNED_POINTER. 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.find(&ty_id) { // Must check both caches!
Some(tc) => { return *tc; }
None => {}
}
cache.insert(ty_id, TC_NONE);
let _i = indenter();
let result = match get(ty).sty {
// Scalar and unique types are sendable, freezable, and durable
ty_nil | ty_bot | ty_bool | ty_int(_) | ty_uint(_) | ty_float(_) |
ty_bare_fn(_) | ty_ptr(_) => {
TC_NONE
}
ty_estr(vstore_uniq) => {
TC_OWNED_VEC
}
ty_closure(ref c) => {
closure_contents(c)
}
ty_box(mt) => {
TC_MANAGED +
statically_sized(nonsendable(tc_mt(cx, mt, cache)))
}
ty_trait(_, _, store, mutbl, bounds) => {
trait_contents(store, mutbl, bounds)
}
ty_rptr(r, mt) => {
borrowed_contents(r, mt.mutbl) +
statically_sized(nonsendable(tc_mt(cx, mt, cache)))
}
ty_uniq(mt) => {
TC_OWNED_POINTER + statically_sized(tc_mt(cx, mt, cache))
}
ty_evec(mt, vstore_uniq) => {
TC_OWNED_VEC + statically_sized(tc_mt(cx, mt, cache))
}
ty_evec(mt, vstore_box) => {
TC_MANAGED +
statically_sized(nonsendable(tc_mt(cx, mt, cache)))
}
ty_evec(mt, vstore_slice(r)) => {
borrowed_contents(r, mt.mutbl) +
statically_sized(nonsendable(tc_mt(cx, mt, cache)))
}
ty_evec(mt, vstore_fixed(_)) => {
let contents = tc_mt(cx, mt, cache);
// FIXME(#6308) Uncomment this when construction of such
// vectors is prevented earlier in compilation.
// if !contents.is_sized(cx) {
// cx.sess.bug("Fixed-length vector of unsized type \
// should be impossible");
// }
contents
}
ty_estr(vstore_box) => {
TC_MANAGED
}
ty_estr(vstore_slice(r)) => {
borrowed_contents(r, m_imm)
}
ty_estr(vstore_fixed(_)) => {
TC_NONE
}
ty_struct(did, ref substs) => {
let flds = struct_fields(cx, did, substs);
let mut res = flds.iter().fold(
TC_NONE,
|tc, f| tc + tc_mt(cx, f.mt, cache));
if ty::has_dtor(cx, did) {
res = res + TC_DTOR;
}
apply_tc_attr(cx, did, res)
}
ty_tup(ref tys) => {
tys.iter().fold(TC_NONE, |tc, ty| tc + tc_ty(cx, *ty, cache))
}
ty_enum(did, ref substs) => {
let variants = substd_enum_variants(cx, did, substs);
let res = if variants.is_empty() {
// we somewhat arbitrary declare that empty enums
// are non-copyable
TC_EMPTY_ENUM
} else {
variants.iter().fold(TC_NONE, |tc, variant| {
variant.args.iter().fold(tc,
|tc, arg_ty| tc + tc_ty(cx, *arg_ty, cache))
})
};
apply_tc_attr(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.crate, ast::local_crate);
type_param_def_to_contents(
cx, cx.ty_param_defs.get(&p.def_id.node))
}
ty_self(_) => {
// Currently, self is not bounded, so we must assume the
// worst. But in the future we should examine the super
// traits.
//
// FIXME(#4678)---self should just be a ty param
TC_ALL
}
ty_infer(_) => {
// This occurs during coherence, but shouldn't occur at other
// times.
TC_ALL
}
ty_opaque_box => TC_MANAGED,
ty_unboxed_vec(mt) => TC_DYNAMIC_SIZE + tc_mt(cx, mt, cache),
ty_opaque_closure_ptr(sigil) => {
match sigil {
ast::BorrowedSigil => TC_BORROWED_POINTER,
ast::ManagedSigil => TC_MANAGED,
// FIXME(#3569): Looks like noncopyability should depend
// on the bounds, but I don't think this case ever comes up.
ast::OwnedSigil => TC_NONCOPY_TRAIT + TC_OWNED_POINTER,
}
}
ty_type => TC_NONE,
ty_err => {
cx.sess.bug("Asked to compute contents of fictitious type");
}
};
cache.insert(ty_id, result);
return result;
}
fn tc_mt(cx: ctxt,
mt: mt,
cache: &mut HashMap<uint, TypeContents>) -> TypeContents
{
let mc = if mt.mutbl == m_mutbl {TC_MUTABLE} else {TC_NONE};
mc + tc_ty(cx, mt.ty, cache)
}
fn apply_tc_attr(cx: ctxt, did: def_id, mut tc: TypeContents) -> TypeContents {
if has_attr(cx, did, "no_freeze") {
tc = tc + TC_MUTABLE;
}
if has_attr(cx, did, "no_send") {
tc = tc + TC_NON_SENDABLE;
}
tc
}
fn borrowed_contents(region: ty::Region,
mutbl: ast::mutability) -> TypeContents
{
let mc = if mutbl == m_mutbl {
TC_MUTABLE + TC_BORROWED_MUT
} else {
TC_NONE
};
let rc = if region != ty::re_static {
TC_BORROWED_POINTER
} else {
TC_NONE
};
mc + rc
}
fn nonsendable(pointee: TypeContents) -> TypeContents {
/*!
*
* Given a non-owning pointer to some type `T` with
* contents `pointee` (like `@T` or
* `&T`), returns the relevant bits that
* apply to the owner of the pointer.
*/
let mask = TC_MUTABLE.bits | TC_BORROWED_POINTER.bits;
TypeContents {bits: pointee.bits & mask}
}
fn statically_sized(pointee: TypeContents) -> TypeContents {
/*!
* If a dynamically-sized type is found behind a pointer, we should
* restore the 'Sized' kind to the pointer and things that contain it.
*/
TypeContents {bits: pointee.bits & !TC_DYNAMIC_SIZE.bits}
}
fn closure_contents(cty: &ClosureTy) -> TypeContents {
// Closure contents are just like trait contents, but with potentially
// even more stuff.
let st = match cty.sigil {
ast::BorrowedSigil =>
trait_contents(RegionTraitStore(cty.region), m_imm, cty.bounds)
+ TC_BORROWED_POINTER, // might be an env packet even if static
ast::ManagedSigil =>
trait_contents(BoxTraitStore, m_imm, cty.bounds),
ast::OwnedSigil =>
trait_contents(UniqTraitStore, m_imm, cty.bounds),
};
// FIXME(#3569): This borrowed_contents call should be taken care of in
// trait_contents, after ~Traits and @Traits can have region bounds too.
// This one here is redundant for &fns but important for ~fns and @fns.
let rt = borrowed_contents(cty.region, m_imm);
// 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_ONCE_CLOSURE,
ast::Many => TC_NONE
};
// Prevent noncopyable types captured in the environment from being copied.
let ct = if cty.bounds.contains_elem(BoundCopy) ||
cty.sigil == ast::ManagedSigil {
TC_NONE
} else {
TC_NONCOPY_TRAIT
};
st + rt + ot + ct
}
fn trait_contents(store: TraitStore, mutbl: ast::mutability,
bounds: BuiltinBounds) -> TypeContents {
let st = match store {
UniqTraitStore => TC_OWNED_POINTER,
BoxTraitStore => TC_MANAGED,
RegionTraitStore(r) => borrowed_contents(r, mutbl),
};
let mt = match mutbl { ast::m_mutbl => TC_MUTABLE, _ => TC_NONE };
// We get additional "special type contents" for each bound that *isn't*
// on the trait. So iterate over the inverse of the bounds that are set.
// This is like with typarams below, but less "pessimistic" and also
// dependent on the trait store.
let mut bt = TC_NONE;
for (AllBuiltinBounds() - bounds).each |bound| {
bt = bt + match bound {
BoundCopy if store == UniqTraitStore
=> TC_NONCOPY_TRAIT,
BoundCopy => TC_NONE, // @Trait/&Trait are copyable either way
BoundStatic if bounds.contains_elem(BoundSend)
=> TC_NONE, // Send bound implies static bound.
BoundStatic => TC_BORROWED_POINTER, // Useful for "@Trait:'static"
BoundSend => TC_NON_SENDABLE,
BoundFreeze => TC_MUTABLE,
BoundSized => TC_NONE, // don't care if interior is sized
};
}
st + mt + bt
}
fn type_param_def_to_contents(cx: ctxt,
type_param_def: &TypeParameterDef) -> TypeContents
{
debug!("type_param_def_to_contents(%s)", type_param_def.repr(cx));
let _i = indenter();
let mut tc = TC_ALL;
for type_param_def.bounds.builtin_bounds.each |bound| {
debug!("tc = %s, bound = %?", tc.to_str(), bound);
tc = tc - match bound {
BoundCopy => TypeContents::noncopyable(cx),
BoundStatic => TypeContents::nonstatic(cx),
BoundSend => TypeContents::nonsendable(cx),
BoundFreeze => TypeContents::nonfreezable(cx),
// The dynamic-size bit can be removed at pointer-level, etc.
BoundSized => TypeContents::dynamically_sized(cx),
};
}
debug!("result = %s", tc.to_str());
return tc;
}
}
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 ~[def_id],
r_ty: t, ty: t) -> bool {
debug!("type_requires(%s, %s)?",
::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(%s, %s)? %b",
::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 ~[def_id],
r_ty: t, ty: t) -> bool {
debug!("subtypes_require(%s, %s)?",
::util::ppaux::ty_to_str(cx, r_ty),
::util::ppaux::ty_to_str(cx, ty));
let r = match get(ty).sty {
ty_nil |
ty_bot |
ty_bool |
ty_int(_) |
ty_uint(_) |
ty_float(_) |
ty_estr(_) |
ty_bare_fn(_) |
ty_closure(_) |
ty_infer(_) |
ty_err |
ty_param(_) |
ty_self(_) |
ty_type |
ty_opaque_box |
ty_opaque_closure_ptr(_) |
ty_evec(_, _) |
ty_unboxed_vec(_) => {
false
}
ty_box(ref mt) |
ty_uniq(ref mt) |
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();
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() && do vs.iter().all |variant| {
do variant.args.iter().any |aty| {
let sty = subst(cx, substs, *aty);
type_requires(cx, seen, r_ty, sty)
}
};
seen.pop();
r
}
};
debug!("subtypes_require(%s, %s)? %b",
::util::ppaux::ty_to_str(cx, r_ty),
::util::ppaux::ty_to_str(cx, ty),
r);
return r;
}
let mut seen = ~[];
!subtypes_require(cx, &mut seen, r_ty, r_ty)
}
pub fn type_structurally_contains(cx: ctxt,
ty: t,
test: &fn(x: &sty) -> bool)
-> bool {
let sty = &get(ty).sty;
debug!("type_structurally_contains: %s",
::util::ppaux::ty_to_str(cx, ty));
if test(sty) { return true; }
match *sty {
ty_enum(did, ref substs) => {
for (*enum_variants(cx, did)).iter().advance |variant| {
for variant.args.iter().advance |aty| {
let sty = subst(cx, substs, *aty);
if type_structurally_contains(cx, sty, |x| test(x)) { return true; }
}
}
return false;
}
ty_struct(did, ref substs) => {
let r = lookup_struct_fields(cx, did);
for r.iter().advance |field| {
let ft = lookup_field_type(cx, did, field.id, substs);
if type_structurally_contains(cx, ft, |x| test(x)) { return true; }
}
return false;
}
ty_tup(ref ts) => {
for ts.iter().advance |tt| {
if type_structurally_contains(cx, *tt, |x| test(x)) { return true; }
}
return false;
}
ty_evec(ref mt, vstore_fixed(_)) => {
return type_structurally_contains(cx, mt.ty, test);
}
_ => return false
}
}
pub fn type_structurally_contains_uniques(cx: ctxt, ty: t) -> bool {
return type_structurally_contains(cx, ty, |sty| {
match *sty {
ty_uniq(_) |
ty_evec(_, vstore_uniq) |
ty_estr(vstore_uniq) => 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_char(ty: t) -> bool {
match get(ty).sty {
ty_int(ty_char) => 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::ty_i) | ty_uint(ast::ty_u) | ty_float(ast::ty_f) => false,
ty_int(*) | ty_uint(*) | ty_float(*) => true,
_ => false
}
}
// Whether a type is Plain Old Data -- meaning it does not contain pointers
// that the cycle collector might care about.
pub fn type_is_pod(cx: ctxt, ty: t) -> bool {
let mut result = true;
match get(ty).sty {
// Scalar types
ty_nil | ty_bot | ty_bool | ty_int(_) | ty_float(_) | ty_uint(_) |
ty_type | ty_ptr(_) | ty_bare_fn(_) => result = true,
// Boxed types
ty_box(_) | ty_uniq(_) | ty_closure(_) |
ty_estr(vstore_uniq) | ty_estr(vstore_box) |
ty_evec(_, vstore_uniq) | ty_evec(_, vstore_box) |
ty_trait(_, _, _, _, _) | ty_rptr(_,_) | ty_opaque_box => result = false,
// Structural types
ty_enum(did, ref substs) => {
let variants = enum_variants(cx, did);
for (*variants).iter().advance |variant| {
let tup_ty = mk_tup(cx, /*bad*/copy variant.args);
// Perform any type parameter substitutions.
let tup_ty = subst(cx, substs, tup_ty);
if !type_is_pod(cx, tup_ty) { result = false; }
}
}
ty_tup(ref elts) => {
for elts.iter().advance |elt| { if !type_is_pod(cx, *elt) { result = false; } }
}
ty_estr(vstore_fixed(_)) => result = true,
ty_evec(ref mt, vstore_fixed(_)) | ty_unboxed_vec(ref mt) => {
result = type_is_pod(cx, mt.ty);
}
ty_param(_) => result = false,
ty_opaque_closure_ptr(_) => result = true,
ty_struct(did, ref substs) => {
let fields = lookup_struct_fields(cx, did);
result = do fields.iter().all |f| {
let fty = ty::lookup_item_type(cx, f.id);
let sty = subst(cx, substs, fty.ty);
type_is_pod(cx, sty)
};
}
ty_estr(vstore_slice(*)) | ty_evec(_, vstore_slice(*)) => {
result = false;
}
ty_infer(*) | ty_self(*) | ty_err => {
cx.sess.bug("non concrete type in type_is_pod");
}
}
return result;
}
pub fn type_is_enum(ty: t) -> bool {
match get(ty).sty {
ty_enum(_, _) => return true,
_ => return false
}
}
// Is the type's representation size known at compile time?
pub fn type_is_sized(cx: ctxt, ty: ty::t) -> bool {
match get(ty).sty {
// FIXME(#6308) add trait, vec, str, etc here.
ty_param(p) => {
let param_def = cx.ty_param_defs.get(&p.def_id.node);
if param_def.bounds.builtin_bounds.contains_elem(BoundSized) {
return true;
}
return false;
},
_ => return true,
}
}
// Whether a type is enum like, that is a 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
}
}
pub fn type_param(ty: t) -> Option<uint> {
match get(ty).sty {
ty_param(p) => return Some(p.idx),
_ => {/* fall through */ }
}
return None;
}
// 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(cx: ctxt, t: t, explicit: bool) -> Option<mt> {
deref_sty(cx, &get(t).sty, explicit)
}
pub fn deref_sty(cx: ctxt, sty: &sty, explicit: bool) -> Option<mt> {
match *sty {
ty_rptr(_, mt) | ty_box(mt) | ty_uniq(mt) => {
Some(mt)
}
ty_ptr(mt) if explicit => {
Some(mt)
}
ty_enum(did, ref substs) => {
let variants = enum_variants(cx, did);
if (*variants).len() == 1u && variants[0].args.len() == 1u {
let v_t = subst(cx, substs, variants[0].args[0]);
Some(mt {ty: v_t, mutbl: ast::m_imm})
} else {
None
}
}
ty_struct(did, ref substs) => {
let fields = struct_fields(cx, did, substs);
if fields.len() == 1 && fields[0].ident ==
syntax::parse::token::special_idents::unnamed_field {
Some(mt {ty: fields[0].mt.ty, mutbl: ast::m_imm})
} else {
None
}
}
_ => None
}
}
pub fn type_autoderef(cx: ctxt, t: t) -> t {
let mut t = t;
loop {
match deref(cx, t, false) {
None => return t,
Some(mt) => t = mt.ty
}
}
}
// Returns the type and mutability of t[i]
pub fn index(t: t) -> Option<mt> {
index_sty(&get(t).sty)
}
pub fn index_sty(sty: &sty) -> Option<mt> {
match *sty {
ty_evec(mt, _) => Some(mt),
ty_estr(_) => Some(mt {ty: mk_u8(), mutbl: ast::m_imm}),
_ => None
}
}
/**
* Enforces an arbitrary but consistent total ordering over
* free regions. This is needed for establishing a consistent
* LUB in region_inference. */
impl cmp::TotalOrd for FreeRegion {
fn cmp(&self, other: &FreeRegion) -> Ordering {
cmp::cmp2(&self.scope_id, &self.bound_region,
&other.scope_id, &other.bound_region)
}
}
impl cmp::TotalEq for FreeRegion {
fn equals(&self, other: &FreeRegion) -> bool {
*self == *other
}
}
/**
* Enforces an arbitrary but consistent total ordering over
* bound regions. This is needed for establishing a consistent
* LUB in region_inference. */
impl cmp::TotalOrd for bound_region {
fn cmp(&self, other: &bound_region) -> Ordering {
match (self, other) {
(&ty::br_self, &ty::br_self) => cmp::Equal,
(&ty::br_self, _) => cmp::Less,
(&ty::br_anon(ref a1), &ty::br_anon(ref a2)) => a1.cmp(a2),
(&ty::br_anon(*), _) => cmp::Less,
(&ty::br_named(ref a1), &ty::br_named(ref a2)) => a1.name.cmp(&a2.name),
(&ty::br_named(*), _) => cmp::Less,
(&ty::br_cap_avoid(ref a1, @ref b1),
&ty::br_cap_avoid(ref a2, @ref b2)) => cmp::cmp2(a1, b1, a2, b2),
(&ty::br_cap_avoid(*), _) => cmp::Less,
(&ty::br_fresh(ref a1), &ty::br_fresh(ref a2)) => a1.cmp(a2),
(&ty::br_fresh(*), _) => cmp::Less,
}
}
}
impl cmp::TotalEq for bound_region {
fn equals(&self, other: &bound_region) -> bool {
*self == *other
}
}
pub fn node_id_to_trait_ref(cx: ctxt, id: ast::node_id) -> @ty::TraitRef {
match cx.trait_refs.find(&id) {
Some(&t) => t,
None => cx.sess.bug(
fmt!("node_id_to_trait_ref: no trait ref for node `%s`",
ast_map::node_id_to_str(cx.items, id,
token::get_ident_interner())))
}
}
pub fn node_id_to_type(cx: ctxt, id: ast::node_id) -> t {
//io::println(fmt!("%?/%?", id, cx.node_types.len()));
match cx.node_types.find(&(id as uint)) {
Some(&t) => t,
None => cx.sess.bug(
fmt!("node_id_to_type: no type for node `%s`",
ast_map::node_id_to_str(cx.items, id,
token::get_ident_interner())))
}
}
pub fn node_id_to_type_params(cx: ctxt, id: ast::node_id) -> ~[t] {
match cx.node_type_substs.find(&id) {
None => return ~[],
Some(ts) => return /*bad*/ copy *ts
}
}
fn node_id_has_type_params(cx: ctxt, id: ast::node_id) -> bool {
cx.node_type_substs.contains_key(&id)
}
pub fn ty_fn_sig(fty: t) -> FnSig {
match get(fty).sty {
ty_bare_fn(ref f) => copy f.sig,
ty_closure(ref f) => copy f.sig,
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) -> ~[t] {
match get(fty).sty {
ty_bare_fn(ref f) => copy f.sig.inputs,
ty_closure(ref f) => copy f.sig.inputs,
ref s => {
fail!("ty_fn_args() called on non-fn type: %?", s)
}
}
}
pub fn ty_closure_sigil(fty: t) -> Sigil {
match get(fty).sty {
ty_closure(ref f) => f.sigil,
ref s => {
fail!("ty_closure_sigil() called on non-closure type: %?", s)
}
}
}
pub fn ty_fn_purity(fty: t) -> ast::purity {
match get(fty).sty {
ty_bare_fn(ref f) => f.purity,
ty_closure(ref f) => f.purity,
ref s => {
fail!("ty_fn_purity() called on non-fn 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_vstore(ty: t) -> vstore {
match get(ty).sty {
ty_evec(_, vstore) => vstore,
ty_estr(vstore) => vstore,
ref s => fail!("ty_vstore() called on invalid sty: %?", s)
}
}
pub fn ty_region(tcx: ctxt,
span: span,
ty: t) -> Region {
match get(ty).sty {
ty_rptr(r, _) => r,
ty_evec(_, vstore_slice(r)) => r,
ty_estr(vstore_slice(r)) => r,
ref s => {
tcx.sess.span_bug(
span,
fmt!("ty_region() invoked on in appropriate ty: %?", s));
}
}
}
pub fn replace_fn_sig(cx: ctxt, fsty: &sty, new_sig: FnSig) -> t {
match *fsty {
ty_bare_fn(ref f) => mk_bare_fn(cx, BareFnTy {sig: new_sig, ..*f}),
ty_closure(ref f) => mk_closure(cx, ClosureTy {sig: new_sig, ..*f}),
ref s => {
cx.sess.bug(
fmt!("ty_fn_sig() called on non-fn type: %?", s));
}
}
}
pub fn replace_closure_return_type(tcx: ctxt, fn_type: t, ret_type: t) -> t {
/*!
*
* Returns a new function type based on `fn_type` but returning a value of
* type `ret_type` instead. */
match ty::get(fn_type).sty {
ty::ty_closure(ref fty) => {
ty::mk_closure(tcx, ClosureTy {
sig: FnSig {output: ret_type, ..copy fty.sig},
..copy *fty
})
}
_ => {
tcx.sess.bug(fmt!(
"replace_fn_ret() invoked with non-fn-type: %s",
ty_to_str(tcx, fn_type)));
}
}
}
// Returns a vec of all the input and output types of fty.
pub fn tys_in_fn_sig(sig: &FnSig) -> ~[t] {
vec::append_one(sig.inputs.map(|a| *a), sig.output)
}
// Type accessors for AST nodes
pub fn block_ty(cx: ctxt, b: &ast::blk) -> t {
return node_id_to_type(cx, b.node.id);
}
// 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_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
*/
let unadjusted_ty = expr_ty(cx, expr);
adjust_ty(cx, expr.span, unadjusted_ty, cx.adjustments.find_copy(&expr.id))
}
pub fn adjust_ty(cx: ctxt,
span: span,
unadjusted_ty: ty::t,
adjustment: Option<@AutoAdjustment>) -> ty::t
{
/*! See `expr_ty_adjusted` */
return match adjustment {
None => unadjusted_ty,
Some(@AutoAddEnv(r, s)) => {
match ty::get(unadjusted_ty).sty {
ty::ty_bare_fn(ref b) => {
ty::mk_closure(
cx,
ty::ClosureTy {purity: b.purity,
sigil: s,
onceness: ast::Many,
region: r,
bounds: ty::AllBuiltinBounds(),
sig: copy b.sig})
}
ref b => {
cx.sess.bug(
fmt!("add_env adjustment on non-bare-fn: %?", b));
}
}
}
Some(@AutoDerefRef(ref adj)) => {
let mut adjusted_ty = unadjusted_ty;
if (!ty::type_is_error(adjusted_ty)) {
for uint::range(0, adj.autoderefs) |i| {
match ty::deref(cx, adjusted_ty, true) {
Some(mt) => { adjusted_ty = mt.ty; }
None => {
cx.sess.span_bug(
span,
fmt!("The %uth autoderef failed: %s",
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::m_imm})
}
AutoBorrowFn(r) => {
borrow_fn(cx, span, r, adjusted_ty)
}
AutoUnsafe(m) => {
mk_ptr(cx, mt {ty: adjusted_ty, mutbl: m})
}
}
}
}
}
};
fn borrow_vec(cx: ctxt, span: span,
r: Region, m: ast::mutability,
ty: ty::t) -> ty::t {
match get(ty).sty {
ty_evec(mt, _) => {
ty::mk_evec(cx, mt {ty: mt.ty, mutbl: m}, vstore_slice(r))
}
ty_estr(_) => {
ty::mk_estr(cx, vstore_slice(r))
}
ref s => {
cx.sess.span_bug(
span,
fmt!("borrow-vec associated with bad sty: %?",
s));
}
}
}
fn borrow_fn(cx: ctxt, span: span, r: Region, ty: ty::t) -> ty::t {
match get(ty).sty {
ty_closure(ref fty) => {
ty::mk_closure(cx, ClosureTy {
sigil: BorrowedSigil,
region: r,
..copy *fty
})
}
ref s => {
cx.sess.span_bug(
span,
fmt!("borrow-fn associated with bad sty: %?",
s));
}
}
}
}
impl AutoRef {
pub fn map_region(&self, f: &fn(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::AutoBorrowFn(r) => ty::AutoBorrowFn(f(r)),
ty::AutoUnsafe(m) => ty::AutoUnsafe(m),
}
}
}
pub struct ParamsTy {
params: ~[t],
ty: t
}
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 expr_has_ty_params(cx: ctxt, expr: &ast::expr) -> bool {
return node_id_has_type_params(cx, expr.id);
}
pub fn method_call_type_param_defs(
tcx: ctxt,
method_map: typeck::method_map,
id: ast::node_id) -> Option<@~[TypeParameterDef]>
{
do method_map.find(&id).map |method| {
match method.origin {
typeck::method_static(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::method_param(typeck::method_param {
trait_id: trt_id,
method_num: n_mth, _}) |
typeck::method_trait(trt_id, n_mth, _) |
typeck::method_self(trt_id, n_mth) |
typeck::method_super(trt_id, 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 =
ty::lookup_trait_def(tcx, trt_id).generics.type_param_defs;
@vec::append(
copy *trait_type_param_defs,
*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.find(&expr.id) {
Some(&def) => def,
None => {
tcx.sess.span_bug(expr.span, fmt!(
"No def-map entry for expr %?", expr.id));
}
}
}
pub fn expr_is_lval(tcx: ctxt,
method_map: typeck::method_map,
e: &ast::expr) -> bool {
match expr_kind(tcx, method_map, 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,
method_map: typeck::method_map,
expr: &ast::expr) -> ExprKind {
if method_map.contains_key(&expr.id) {
// Overloaded operations are generally calls, and hence they are
// generated via DPS. However, assign_op (e.g., `x += y`) is an
// exception, as its result is always unit.
return match expr.node {
ast::expr_assign_op(*) => RvalueStmtExpr,
_ => RvalueDpsExpr
};
}
match expr.node {
ast::expr_path(*) | ast::expr_self => {
match resolve_expr(tcx, expr) {
ast::def_variant(*) | ast::def_struct(*) => RvalueDpsExpr,
// Fn pointers are just scalar values.
ast::def_fn(*) | ast::def_static_method(*) => RvalueDatumExpr,
// Note: there is actually a good case to be made that
// def_args, particularly those of immediate type, ought to
// considered rvalues.
ast::def_static(*) |
ast::def_binding(*) |
ast::def_upvar(*) |
ast::def_arg(*) |
ast::def_local(*) |
ast::def_self(*) => LvalueExpr,
def => {
tcx.sess.span_bug(expr.span, fmt!(
"Uncategorized def for expr %?: %?",
expr.id, def));
}
}
}
ast::expr_unary(_, ast::deref, _) |
ast::expr_field(*) |
ast::expr_index(*) => {
LvalueExpr
}
ast::expr_call(*) |
ast::expr_method_call(*) |
ast::expr_struct(*) |
ast::expr_tup(*) |
ast::expr_if(*) |
ast::expr_match(*) |
ast::expr_fn_block(*) |
ast::expr_loop_body(*) |
ast::expr_do_body(*) |
ast::expr_block(*) |
ast::expr_copy(*) |
ast::expr_repeat(*) |
ast::expr_lit(@codemap::spanned {node: lit_str(_), _}) |
ast::expr_vstore(_, ast::expr_vstore_slice) |
ast::expr_vstore(_, ast::expr_vstore_mut_slice) |
ast::expr_vec(*) => {
RvalueDpsExpr
}
ast::expr_cast(*) => {
match tcx.node_types.find(&(expr.id as uint)) {
Some(&t) => {
if ty::type_is_immediate(tcx, t) {
RvalueDatumExpr
} else {
RvalueDpsExpr
}
}
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
// like @Foo, ~Foo, or &Foo.
RvalueDatumExpr
}
}
}
ast::expr_break(*) |
ast::expr_again(*) |
ast::expr_ret(*) |
ast::expr_log(*) |
ast::expr_while(*) |
ast::expr_loop(*) |
ast::expr_assign(*) |
ast::expr_inline_asm(*) |
ast::expr_assign_op(*) => {
RvalueStmtExpr
}
ast::expr_lit(_) | // Note: lit_str is carved out above
ast::expr_unary(*) |
ast::expr_addr_of(*) |
ast::expr_binary(*) |
ast::expr_vstore(_, ast::expr_vstore_box) |
ast::expr_vstore(_, ast::expr_vstore_mut_box) |
ast::expr_vstore(_, ast::expr_vstore_uniq) => {
RvalueDatumExpr
}
ast::expr_paren(e) => expr_kind(tcx, method_map, e),
ast::expr_mac(*) => {
tcx.sess.span_bug(
expr.span,
"macro expression remains after expansion");
}
}
}
pub fn stmt_node_id(s: &ast::stmt) -> ast::node_id {
match s.node {
ast::stmt_decl(_, id) | stmt_expr(_, id) | stmt_semi(_, id) => {
return id;
}
ast::stmt_mac(*) => fail!("unexpanded macro in trans")
}
}
pub fn field_idx(id: ast::ident, fields: &[field]) -> Option<uint> {
let mut i = 0u;
for fields.iter().advance |f| { if f.ident == id { return Some(i); } i += 1u; }
return None;
}
pub fn field_idx_strict(tcx: ty::ctxt, id: ast::ident, fields: &[field])
-> uint {
let mut i = 0u;
for fields.iter().advance |f| { if f.ident == id { return i; } i += 1u; }
tcx.sess.bug(fmt!(
"No field named `%s` found in the list of fields `%?`",
tcx.sess.str_of(id),
fields.map(|f| tcx.sess.str_of(f.ident))));
}
pub fn method_idx(id: ast::ident, meths: &[@Method]) -> Option<uint> {
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) -> ~[param_ty] {
let mut rslt = ~[];
do walk_ty(ty) |ty| {
match get(ty).sty {
ty_param(p) => {
rslt.push(p);
}
_ => ()
}
}
rslt
}
pub fn occurs_check(tcx: ctxt, sp: span, vid: TyVid, rt: t) {
// Returns a vec of all the type variables occurring in `ty`. It may
// contain duplicates. (Integral type vars aren't counted.)
fn vars_in_type(ty: t) -> ~[TyVid] {
let mut rslt = ~[];
do walk_ty(ty) |ty| {
match get(ty).sty {
ty_infer(TyVar(v)) => rslt.push(v),
_ => ()
}
}
rslt
}
// Fast path
if !type_needs_infer(rt) { return; }
// Occurs check!
if vars_in_type(rt).contains(&vid) {
// Maybe this should be span_err -- however, there's an
// assertion later on that the type doesn't contain
// variables, so in this case we have to be sure to die.
tcx.sess.span_fatal
(sp, ~"type inference failed because I \
could not find a type\n that's both of the form "
+ ::util::ppaux::ty_to_str(tcx, mk_var(tcx, vid)) +
" and of the form " + ::util::ppaux::ty_to_str(tcx, rt) +
" - such a type would have to be infinitely large.");
}
}
pub fn ty_sort_str(cx: ctxt, t: t) -> ~str {
match get(t).sty {
ty_nil | ty_bot | ty_bool | ty_int(_) |
ty_uint(_) | ty_float(_) | ty_estr(_) |
ty_type | ty_opaque_box | ty_opaque_closure_ptr(_) => {
::util::ppaux::ty_to_str(cx, t)
}
ty_enum(id, _) => fmt!("enum %s", item_path_str(cx, id)),
ty_box(_) => ~"@-ptr",
ty_uniq(_) => ~"~-ptr",
ty_evec(_, _) => ~"vector",
ty_unboxed_vec(_) => ~"unboxed vector",
ty_ptr(_) => ~"*-ptr",
ty_rptr(_, _) => ~"&-ptr",
ty_bare_fn(_) => ~"extern fn",
ty_closure(_) => ~"fn",
ty_trait(id, _, _, _, _) => fmt!("trait %s", item_path_str(cx, id)),
ty_struct(id, _) => fmt!("struct %s", item_path_str(cx, id)),
ty_tup(_) => ~"tuple",
ty_infer(TyVar(_)) => ~"inferred type",
ty_infer(IntVar(_)) => ~"integral variable",
ty_infer(FloatVar(_)) => ~"floating-point variable",
ty_param(_) => ~"type parameter",
ty_self(_) => ~"self",
ty_err => ~"type error"
}
}
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 terr_vstore_kind_to_str(k: terr_vstore_kind) -> ~str {
match k {
terr_vec => ~"[]",
terr_str => ~"str",
terr_fn => ~"fn",
terr_trait => ~"trait"
}
}
match *err {
terr_mismatch => ~"types differ",
terr_purity_mismatch(values) => {
fmt!("expected %s fn but found %s fn",
values.expected.to_str(), values.found.to_str())
}
terr_abi_mismatch(values) => {
fmt!("expected %s fn but found %s fn",
values.expected.to_str(), values.found.to_str())
}
terr_onceness_mismatch(values) => {
fmt!("expected %s fn but found %s fn",
values.expected.to_str(), values.found.to_str())
}
terr_sigil_mismatch(values) => {
fmt!("expected %s closure, found %s closure",
values.expected.to_str(),
values.found.to_str())
}
terr_mutability => ~"values differ in mutability",
terr_box_mutability => ~"boxed values differ in mutability",
terr_vec_mutability => ~"vectors differ in mutability",
terr_ptr_mutability => ~"pointers differ in mutability",
terr_ref_mutability => ~"references differ in mutability",
terr_ty_param_size(values) => {
fmt!("expected a type with %? type params \
but found one with %? type params",
values.expected, values.found)
}
terr_tuple_size(values) => {
fmt!("expected a tuple with %? elements \
but found one with %? elements",
values.expected, values.found)
}
terr_record_size(values) => {
fmt!("expected a record with %? fields \
but found one with %? fields",
values.expected, values.found)
}
terr_record_mutability => {
~"record elements differ in mutability"
}
terr_record_fields(values) => {
fmt!("expected a record with field `%s` but found one with field \
`%s`",
cx.sess.str_of(values.expected),
cx.sess.str_of(values.found))
}
terr_arg_count => ~"incorrect number of function parameters",
terr_regions_does_not_outlive(*) => {
fmt!("lifetime mismatch")
}
terr_regions_not_same(*) => {
fmt!("lifetimes are not the same")
}
terr_regions_no_overlap(*) => {
fmt!("lifetimes do not intersect")
}
terr_regions_insufficiently_polymorphic(br, _) => {
fmt!("expected bound lifetime parameter %s, \
but found concrete lifetime",
bound_region_ptr_to_str(cx, br))
}
terr_regions_overly_polymorphic(br, _) => {
fmt!("expected concrete lifetime, \
but found bound lifetime parameter %s",
bound_region_ptr_to_str(cx, br))
}
terr_vstores_differ(k, ref values) => {
fmt!("%s storage differs: expected %s but found %s",
terr_vstore_kind_to_str(k),
vstore_to_str(cx, (*values).expected),
vstore_to_str(cx, (*values).found))
}
terr_trait_stores_differ(_, ref values) => {
fmt!("trait storage differs: expected %s but found %s",
trait_store_to_str(cx, (*values).expected),
trait_store_to_str(cx, (*values).found))
}
terr_in_field(err, fname) => {
fmt!("in field `%s`, %s", cx.sess.str_of(fname),
type_err_to_str(cx, err))
}
terr_sorts(values) => {
fmt!("expected %s but found %s",
ty_sort_str(cx, values.expected),
ty_sort_str(cx, values.found))
}
terr_traits(values) => {
fmt!("expected trait %s but found trait %s",
item_path_str(cx, values.expected),
item_path_str(cx, values.found))
}
terr_builtin_bounds(values) => {
if values.expected.is_empty() {
fmt!("expected no bounds but found `%s`",
values.found.user_string(cx))
} else if values.found.is_empty() {
fmt!("expected bounds `%s` but found no bounds",
values.expected.user_string(cx))
} else {
fmt!("expected bounds `%s` but found bounds `%s`",
values.expected.user_string(cx),
values.found.user_string(cx))
}
}
terr_integer_as_char => {
fmt!("expected an integral type but found char")
}
terr_int_mismatch(ref values) => {
fmt!("expected %s but found %s",
values.expected.to_str(),
values.found.to_str())
}
terr_float_mismatch(ref values) => {
fmt!("expected %s but found %s",
values.expected.to_str(),
values.found.to_str())
}
}
}
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 def_has_ty_params(def: ast::def) -> bool {
match def {
ast::def_fn(_, _) | ast::def_variant(_, _) | ast::def_struct(_)
=> true,
_ => false
}
}
pub fn provided_trait_methods(cx: ctxt, id: ast::def_id) -> ~[@Method] {
if is_local(id) {
match cx.items.find(&id.node) {
Some(&ast_map::node_item(@ast::item {
node: item_trait(_, _, ref ms),
_
}, _)) =>
match ast_util::split_trait_methods(*ms) {
(_, p) => p.map(|m| method(cx, ast_util::local_def(m.id)))
},
_ => cx.sess.bug(fmt!("provided_trait_methods: %? is not a trait",
id))
}
} else {
csearch::get_provided_trait_methods(cx, id)
}
}
pub fn trait_supertraits(cx: ctxt,
id: ast::def_id) -> @~[@TraitRef]
{
// Check the cache.
match cx.supertraits.find(&id) {
Some(&trait_refs) => { return trait_refs; }
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 = @csearch::get_supertraits(cx, id);
cx.supertraits.insert(id, result);
return result;
}
pub fn trait_ref_supertraits(cx: ctxt, trait_ref: &ty::TraitRef) -> ~[@TraitRef] {
let supertrait_refs = trait_supertraits(cx, trait_ref.def_id);
supertrait_refs.map(
|supertrait_ref| supertrait_ref.subst(cx, &trait_ref.substs))
}
fn lookup_locally_or_in_crate_store<V:Copy>(
descr: &str,
def_id: ast::def_id,
map: &mut HashMap<ast::def_id, V>,
load_external: &fn() -> 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(&def_id) {
Some(&ref v) => { return copy *v; }
None => { }
}
if def_id.crate == ast::local_crate {
fail!("No def'n found for %? in tcx.%s", def_id, descr);
}
let v = load_external();
map.insert(def_id, copy v);
return copy v;
}
pub fn trait_method(cx: ctxt, trait_did: ast::def_id, idx: uint) -> @Method {
let method_def_id = ty::trait_method_def_ids(cx, trait_did)[idx];
ty::method(cx, method_def_id)
}
pub fn add_base_impl(cx: ctxt, base_def_id: def_id, implementation: @Impl) {
let implementations;
match cx.base_impls.find(&base_def_id) {
None => {
implementations = @mut ~[];
cx.base_impls.insert(base_def_id, implementations);
}
Some(&existing) => {
implementations = existing;
}
}
implementations.push(implementation);
}
pub fn trait_methods(cx: ctxt, trait_did: ast::def_id) -> @~[@Method] {
match cx.trait_methods_cache.find(&trait_did) {
Some(&methods) => methods,
None => {
let def_ids = ty::trait_method_def_ids(cx, trait_did);
let methods = @def_ids.map(|d| ty::method(cx, *d));
cx.trait_methods_cache.insert(trait_did, methods);
methods
}
}
}
pub fn method(cx: ctxt, id: ast::def_id) -> @Method {
lookup_locally_or_in_crate_store(
"methods", id, cx.methods,
|| @csearch::get_method(cx, id))
}
pub fn trait_method_def_ids(cx: ctxt, id: ast::def_id) -> @~[def_id] {
lookup_locally_or_in_crate_store(
"methods", id, cx.trait_method_def_ids,
|| @csearch::get_trait_method_def_ids(cx.cstore, id))
}
pub fn impl_trait_ref(cx: ctxt, id: ast::def_id) -> Option<@TraitRef> {
*do cx.impl_trait_cache.find_or_insert_with(id) |_| {
if id.crate == ast::local_crate {
debug!("(impl_trait_ref) searching for trait impl %?", id);
match cx.items.find(&id.node) {
Some(&ast_map::node_item(@ast::item {
node: ast::item_impl(_, ref opt_trait, _, _),
_},
_)) => {
match opt_trait {
&Some(ref t) => Some(ty::node_id_to_trait_ref(cx, t.ref_id)),
&None => None
}
}
_ => None
}
} else {
csearch::get_impl_trait(cx, id)
}
}
}
pub fn ty_to_def_id(ty: t) -> Option<ast::def_id> {
match get(ty).sty {
ty_trait(id, _, _, _, _) | ty_struct(id, _) | ty_enum(id, _) => Some(id),
_ => None
}
}
/// Returns the def ID of the constructor for the given tuple-like struct, or
/// None if the struct is not tuple-like. Fails if the given def ID does not
/// refer to a struct at all.
fn struct_ctor_id(cx: ctxt, struct_did: ast::def_id) -> Option<ast::def_id> {
if struct_did.crate != ast::local_crate {
// XXX: Cross-crate functionality.
cx.sess.unimpl("constructor ID of cross-crate tuple structs");
}
match cx.items.find(&struct_did.node) {
Some(&ast_map::node_item(item, _)) => {
match item.node {
ast::item_struct(struct_def, _) => {
struct_def.ctor_id.map(|ctor_id|
ast_util::local_def(*ctor_id))
}
_ => cx.sess.bug("called struct_ctor_id on non-struct")
}
}
_ => cx.sess.bug("called struct_ctor_id on non-struct")
}
}
// Enum information
pub struct VariantInfo_ {
args: ~[t],
ctor_ty: t,
name: ast::ident,
id: ast::def_id,
disr_val: int,
vis: visibility
}
pub type VariantInfo = @VariantInfo_;
pub fn substd_enum_variants(cx: ctxt,
id: ast::def_id,
substs: &substs)
-> ~[VariantInfo] {
do enum_variants(cx, id).iter().transform |variant_info| {
let substd_args = variant_info.args.iter()
.transform(|aty| subst(cx, substs, *aty)).collect();
let substd_ctor_ty = subst(cx, substs, variant_info.ctor_ty);
@VariantInfo_{args: substd_args, ctor_ty: substd_ctor_ty,
../*bad*/copy **variant_info}
}.collect()
}
pub fn item_path_str(cx: ctxt, id: ast::def_id) -> ~str {
ast_map::path_to_str(item_path(cx, id), token::get_ident_interner())
}
pub enum DtorKind {
NoDtor,
TraitDtor(def_id, 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: def_id) -> DtorKind {
match cx.destructor_for_type.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: def_id) -> bool {
ty_dtor(cx, struct_id).is_present()
}
pub fn item_path(cx: ctxt, id: ast::def_id) -> ast_map::path {
if id.crate != ast::local_crate {
csearch::get_item_path(cx, id)
} else {
// FIXME (#5521): uncomment this code and don't have a catch-all at the
// end of the match statement. Favor explicitly listing
// each variant.
// let node = cx.items.get(&id.node);
// match *node {
match *cx.items.get(&id.node) {
ast_map::node_item(item, path) => {
let item_elt = match item.node {
item_mod(_) | item_foreign_mod(_) => {
ast_map::path_mod(item.ident)
}
_ => {
ast_map::path_name(item.ident)
}
};
vec::append_one(/*bad*/copy *path, item_elt)
}
ast_map::node_foreign_item(nitem, _, _, path) => {
vec::append_one(/*bad*/copy *path,
ast_map::path_name(nitem.ident))
}
ast_map::node_method(method, _, path) => {
vec::append_one(/*bad*/copy *path,
ast_map::path_name(method.ident))
}
ast_map::node_trait_method(trait_method, _, path) => {
let method = ast_util::trait_method_to_ty_method(&*trait_method);
vec::append_one(/*bad*/copy *path,
ast_map::path_name(method.ident))
}
ast_map::node_variant(ref variant, _, path) => {
vec::append_one(path.init().to_owned(),
ast_map::path_name((*variant).node.name))
}
ast_map::node_struct_ctor(_, item, path) => {
vec::append_one(/*bad*/copy *path, ast_map::path_name(item.ident))
}
ref node => {
cx.sess.bug(fmt!("cannot find item_path for node %?", node));
}
}
}
}
pub fn enum_is_univariant(cx: ctxt, id: ast::def_id) -> 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::def_id) -> @~[VariantInfo] {
match cx.enum_var_cache.find(&id) {
Some(&variants) => return variants,
_ => { /* fallthrough */ }
}
let result = if ast::local_crate != id.crate {
@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.items.get_copy(&id.node) {
ast_map::node_item(@ast::item {
node: ast::item_enum(ref enum_definition, _),
_
}, _) => {
let mut disr_val = -1;
@enum_definition.variants.iter().transform(|variant| {
let ctor_ty = node_id_to_type(cx, variant.node.id);
match variant.node.kind {
ast::tuple_variant_kind(ref args) => {
let arg_tys = if args.len() > 0u {
ty_fn_args(ctor_ty).map(|a| *a) }
else {
~[]
};
match variant.node.disr_expr {
Some (ex) => {
disr_val = match const_eval::eval_const_expr(cx,
ex) {
const_eval::const_int(val) => val as int,
_ => cx.sess.bug("enum_variants: bad disr expr")
}
}
_ => disr_val += 1
}
@VariantInfo_{
args: arg_tys,
ctor_ty: ctor_ty,
name: variant.node.name,
id: ast_util::local_def(variant.node.id),
disr_val: disr_val,
vis: variant.node.vis
}
},
ast::struct_variant_kind(struct_def) => {
let arg_tys =
// Is this check needed for structs too, or are they always guaranteed
// to have a valid constructor function?
if struct_def.fields.len() > 0 {
ty_fn_args(ctor_ty).map(|a| *a)
} else {
~[]
};
assert!(variant.node.disr_expr.is_none());
disr_val += 1;
@VariantInfo_{
args: arg_tys,
ctor_ty: ctor_ty,
name: variant.node.name,
id: ast_util::local_def(variant.node.id),
disr_val: disr_val,
vis: variant.node.vis
}
}
}
}).collect()
}
_ => cx.sess.bug("enum_variants: id not bound to an enum")
}
};
cx.enum_var_cache.insert(id, result);
result
}
// Returns information about the enum variant with the given ID:
pub fn enum_variant_with_id(cx: ctxt,
enum_id: ast::def_id,
variant_id: ast::def_id)
-> VariantInfo {
let variants = enum_variants(cx, enum_id);
let mut i = 0;
while i < variants.len() {
let variant = variants[i];
if variant.id == variant_id { return variant; }
i += 1;
}
cx.sess.bug("enum_variant_with_id(): no variant exists with that ID");
}
// 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::def_id)
-> ty_param_bounds_and_ty {
lookup_locally_or_in_crate_store(
"tcache", did, cx.tcache,
|| csearch::get_type(cx, did))
}
/// Given the did of a trait, returns its canonical trait ref.
pub fn lookup_trait_def(cx: ctxt, did: ast::def_id) -> @ty::TraitDef {
match cx.trait_defs.find(&did) {
Some(&trait_def) => {
// The item is in this crate. The caller should have added it to the
// type cache already
return trait_def;
}
None => {
assert!(did.crate != ast::local_crate);
let trait_def = @csearch::get_trait_def(cx, did);
cx.trait_defs.insert(did, trait_def);
return trait_def;
}
}
}
/// Determine whether an item is annotated with an attribute
pub fn has_attr(tcx: ctxt, did: def_id, attr: &str) -> bool {
if is_local(did) {
match tcx.items.find(&did.node) {
Some(
&ast_map::node_item(@ast::item {
attrs: ref attrs,
_
}, _)) => attr::attrs_contains_name(*attrs, attr),
_ => tcx.sess.bug(fmt!("has_attr: %? is not an item",
did))
}
} else {
let mut ret = false;
do csearch::get_item_attrs(tcx.cstore, did) |meta_items| {
ret = ret || attr::contains_name(meta_items, attr);
}
ret
}
}
/// Determine whether an item is annotated with `#[packed]`
pub fn lookup_packed(tcx: ctxt, did: def_id) -> bool {
has_attr(tcx, did, "packed")
}
/// Determine whether an item is annotated with `#[simd]`
pub fn lookup_simd(tcx: ctxt, did: def_id) -> bool {
has_attr(tcx, did, "simd")
}
// 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: def_id,
id: def_id,
substs: &substs)
-> ty::t {
let t = if id.crate == ast::local_crate {
node_id_to_type(tcx, id.node)
}
else {
match tcx.tcache.find(&id) {
Some(&ty_param_bounds_and_ty {ty, _}) => ty,
None => {
let tpt = csearch::get_field_type(tcx, struct_id, id);
tcx.tcache.insert(id, tpt);
tpt.ty
}
}
};
subst(tcx, substs, t)
}
// 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::def_id) -> ~[field_ty] {
if did.crate == ast::local_crate {
match cx.items.find(&did.node) {
Some(&ast_map::node_item(i,_)) => {
match i.node {
ast::item_struct(struct_def, _) => {
struct_field_tys(struct_def.fields)
}
_ => cx.sess.bug("struct ID bound to non-struct")
}
}
Some(&ast_map::node_variant(ref variant, _, _)) => {
match (*variant).node.kind {
ast::struct_variant_kind(struct_def) => {
struct_field_tys(struct_def.fields)
}
_ => {
cx.sess.bug("struct ID bound to enum variant that isn't \
struct-like")
}
}
}
_ => {
cx.sess.bug(
fmt!("struct ID not bound to an item: %s",
ast_map::node_id_to_str(cx.items, did.node,
token::get_ident_interner())));
}
}
}
else {
return csearch::get_struct_fields(cx.sess.cstore, did);
}
}
pub fn lookup_struct_field(cx: ctxt,
parent: ast::def_id,
field_id: ast::def_id)
-> 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")
}
}
fn struct_field_tys(fields: &[@struct_field]) -> ~[field_ty] {
do fields.map |field| {
match field.node.kind {
named_field(ident, visibility) => {
field_ty {
ident: ident,
id: ast_util::local_def(field.node.id),
vis: visibility,
}
}
unnamed_field => {
field_ty {
ident:
syntax::parse::token::special_idents::unnamed_field,
id: ast_util::local_def(field.node.id),
vis: ast::public,
}
}
}
}
}
// 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::def_id, substs: &substs)
-> ~[field] {
do lookup_struct_fields(cx, did).map |f| {
field {
ident: f.ident,
mt: mt {
ty: lookup_field_type(cx, did, f.id, substs),
mutbl: m_imm
}
}
}
}
pub fn is_binopable(_cx: ctxt, ty: t, op: ast::binop) -> bool {
static tycat_other: int = 0;
static tycat_bool: int = 1;
static tycat_int: int = 2;
static tycat_float: int = 3;
static tycat_struct: int = 4;
static tycat_bot: int = 5;
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;
fn opcat(op: ast::binop) -> int {
match op {
ast::add => opcat_add,
ast::subtract => opcat_sub,
ast::mul => opcat_mult,
ast::div => opcat_mult,
ast::rem => opcat_mult,
ast::and => opcat_logic,
ast::or => opcat_logic,
ast::bitxor => opcat_bit,
ast::bitand => opcat_bit,
ast::bitor => opcat_bit,
ast::shl => opcat_shift,
ast::shr => opcat_shift,
ast::eq => opcat_eq,
ast::ne => opcat_eq,
ast::lt => opcat_rel,
ast::le => opcat_rel,
ast::ge => opcat_rel,
ast::gt => opcat_rel
}
}
fn tycat(ty: t) -> int {
match get(ty).sty {
ty_bool => tycat_bool,
ty_int(_) | ty_uint(_) | ty_infer(IntVar(_)) => tycat_int,
ty_float(_) | ty_infer(FloatVar(_)) => tycat_float,
ty_tup(_) | ty_enum(_, _) => tycat_struct,
ty_bot => tycat_bot,
_ => tycat_other
}
}
static t: bool = true;
static f: bool = false;
let tbl = ~[
/*. add, shift, bit
. sub, rel, logic
. mult, eq, */
/*other*/ ~[f, f, f, f, f, f, f, f],
/*bool*/ ~[f, f, f, f, t, t, t, t],
/*int*/ ~[t, t, t, t, t, t, t, f],
/*float*/ ~[t, t, t, f, t, t, f, f],
/*bot*/ ~[f, f, f, f, f, f, f, f],
/*struct*/ ~[t, t, t, t, f, f, t, t]];
return tbl[tycat(ty)][opcat(op)];
}
pub fn ty_params_to_tys(tcx: ty::ctxt, generics: &ast::Generics) -> ~[t] {
vec::from_fn(generics.ty_params.len(), |i| {
let id = generics.ty_params.get(i).id;
ty::mk_param(tcx, i, ast_util::local_def(id))
})
}
/// Returns an equivalent type with all the typedefs and self regions removed.
pub fn normalize_ty(cx: ctxt, t: t) -> t {
fn normalize_mt(cx: ctxt, mt: mt) -> mt {
mt { ty: normalize_ty(cx, mt.ty), mutbl: mt.mutbl }
}
fn normalize_vstore(vstore: vstore) -> vstore {
match vstore {
vstore_fixed(*) | vstore_uniq | vstore_box => vstore,
vstore_slice(_) => vstore_slice(re_static)
}
}
match cx.normalized_cache.find(&t) {
Some(&t) => return t,
None => ()
}
let t = match get(t).sty {
ty_evec(mt, vstore) =>
// This type has a vstore. Get rid of it
mk_evec(cx, normalize_mt(cx, mt), normalize_vstore(vstore)),
ty_estr(vstore) =>
// This type has a vstore. Get rid of it
mk_estr(cx, normalize_vstore(vstore)),
ty_rptr(_, mt) =>
// This type has a region. Get rid of it
mk_rptr(cx, re_static, normalize_mt(cx, mt)),
ty_closure(ref closure_ty) => {
mk_closure(cx, ClosureTy {
region: ty::re_static,
..copy *closure_ty
})
}
ty_enum(did, ref r) =>
match (*r).self_r {
Some(_) =>
// Use re_static since trans doesn't care about regions
mk_enum(cx, did,
substs {
self_r: Some(ty::re_static),
self_ty: None,
tps: /*bad*/copy (*r).tps
}),
None =>
t
},
ty_struct(did, ref r) =>
match (*r).self_r {
Some(_) =>
// Ditto.
mk_struct(cx, did, substs {self_r: Some(ty::re_static),
self_ty: None,
tps: /*bad*/copy (*r).tps}),
None =>
t
},
_ =>
t
};
let sty = fold_sty(&get(t).sty, |t| { normalize_ty(cx, t) });
let t_norm = mk_t(cx, sty);
cx.normalized_cache.insert(t, t_norm);
return t_norm;
}
// Returns the repeat count for a repeating vector expression.
pub fn eval_repeat_count(tcx: ctxt, 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.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.sess.span_err(count_expr.span,
"expected positive integer for \
repeat count but found float");
return count as uint;
}
const_eval::const_str(_) => {
tcx.sess.span_err(count_expr.span,
"expected positive integer for \
repeat count but found string");
return 0;
}
const_eval::const_bool(_) => {
tcx.sess.span_err(count_expr.span,
"expected positive integer for \
repeat count but found boolean");
return 0;
}
},
Err(*) => {
tcx.sess.span_err(count_expr.span,
"expected constant integer for repeat count \
but found variable");
return 0;
}
}
}
// Determine what purity to check a nested function under
pub fn determine_inherited_purity(parent: (ast::purity, ast::node_id),
child: (ast::purity, ast::node_id),
child_sigil: ast::Sigil)
-> (ast::purity, ast::node_id) {
// If the closure is a stack closure and hasn't had some non-standard
// purity inferred for it, then check it under its parent's purity.
// Otherwise, use its own
match child_sigil {
ast::BorrowedSigil if child.first() == ast::impure_fn => parent,
_ => child
}
}
// 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: &ParamBounds,
f: &fn(@TraitRef) -> bool) -> bool {
for bounds.trait_bounds.iter().advance |&bound_trait_ref| {
let mut supertrait_set = HashMap::new();
let mut trait_refs = ~[];
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);
// Add the given trait ty to the hash map
while i < trait_refs.len() {
debug!("each_bound_trait_and_supertraits(i=%?, trait_ref=%s)",
i, trait_refs[i].repr(tcx));
if !f(trait_refs[i]) {
return false;
}
// Add supertraits to supertrait_set
let supertrait_refs = trait_ref_supertraits(tcx, trait_refs[i]);
for supertrait_refs.iter().advance |&supertrait_ref| {
debug!("each_bound_trait_and_supertraits(supertrait_ref=%s)",
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);
}
}
i += 1;
}
}
return true;
}
pub fn count_traits_and_supertraits(tcx: ctxt,
type_param_defs: &[TypeParameterDef]) -> uint {
let mut total = 0;
for type_param_defs.iter().advance |type_param_def| {
for each_bound_trait_and_supertraits(tcx, type_param_def.bounds) |_| {
total += 1;
}
}
return total;
}
// Given a trait and a type, returns the impl of that type
pub fn get_impl_id(tcx: ctxt, trait_id: def_id, self_ty: t) -> def_id {
match tcx.trait_impls.find(&trait_id) {
Some(ty_to_impl) => match ty_to_impl.find(&self_ty) {
Some(the_impl) => the_impl.did,
None => // try autoderef!
match deref(tcx, self_ty, false) {
Some(some_ty) => get_impl_id(tcx, trait_id, some_ty.ty),
None => tcx.sess.bug("get_impl_id: no impl of trait for \
this type")
}
},
None => tcx.sess.bug("get_impl_id: trait isn't in trait_impls")
}
}
pub fn get_tydesc_ty(tcx: ctxt) -> t {
let tydesc_lang_item = tcx.lang_items.ty_desc();
tcx.intrinsic_defs.find_copy(&tydesc_lang_item)
.expect("Failed to resolve TyDesc")
}
pub fn get_opaque_ty(tcx: ctxt) -> t {
let opaque_lang_item = tcx.lang_items.opaque();
tcx.intrinsic_defs.find_copy(&opaque_lang_item)
.expect("Failed to resolve Opaque")
}
pub fn visitor_object_ty(tcx: ctxt) -> (@TraitRef, t) {
let substs = substs {
self_r: None,
self_ty: None,
tps: ~[]
};
let trait_lang_item = tcx.lang_items.ty_visitor();
let trait_ref = @TraitRef { def_id: trait_lang_item, substs: substs };
let mut static_trait_bound = EmptyBuiltinBounds();
static_trait_bound.add(BoundStatic);
(trait_ref,
mk_trait(tcx, trait_ref.def_id, copy trait_ref.substs,
BoxTraitStore, ast::m_imm, static_trait_bound))
}