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use hair::*;
use rustc::mir::transform::MirSource;
use rustc::middle::const_val::ConstVal;
use rustc_const_eval::{ConstContext, fatal_const_eval_err};
use rustc_data_structures::indexed_vec::Idx;
use rustc::hir::def_id::DefId;
use rustc::hir::map::blocks::FnLikeNode;
use rustc::infer::InferCtxt;
use rustc::ty::subst::Subst;
use rustc::ty::{self, Ty, TyCtxt};
use syntax::symbol::{Symbol, InternedString};
use rustc::hir;
use rustc_const_math::{ConstInt, ConstUsize};
#[derive(Copy, Clone)]
pub struct Cx<'a, 'gcx: 'a + 'tcx, 'tcx: 'a> {
tcx: TyCtxt<'a, 'gcx, 'tcx>,
infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
constness: hir::Constness,
check_overflow: bool,
}
impl<'a, 'gcx, 'tcx> Cx<'a, 'gcx, 'tcx> {
pub fn new(infcx: &'a InferCtxt<'a, 'gcx, 'tcx>, src: MirSource) -> Cx<'a, 'gcx, 'tcx> {
let constness = match src {
MirSource::Const(_) |
MirSource::Static(..) => hir::Constness::Const,
MirSource::Fn(id) => {
let fn_like = FnLikeNode::from_node(infcx.tcx.hir.get(id));
fn_like.map_or(hir::Constness::NotConst, |f| f.constness())
}
MirSource::Promoted(..) => bug!(),
};
let attrs = infcx.tcx.hir.attrs(src.item_id());
let mut check_overflow = attrs.iter()
.any(|item| item.check_name("rustc_inherit_overflow_checks"));
check_overflow |= infcx.tcx.sess.overflow_checks();
check_overflow |= constness == hir::Constness::Const;
Cx {
tcx: infcx.tcx,
infcx: infcx,
constness: constness,
check_overflow: check_overflow,
}
}
}
impl<'a, 'gcx, 'tcx> Cx<'a, 'gcx, 'tcx> {
pub fn mirror<M: Mirror<'tcx>>(&mut self, ast: M) -> M::Output {
ast.make_mirror(self)
}
pub fn usize_ty(&mut self) -> Ty<'tcx> {
self.tcx.types.usize
}
pub fn usize_literal(&mut self, value: u64) -> Literal<'tcx> {
match ConstUsize::new(value, self.tcx.sess.target.uint_type) {
Ok(val) => Literal::Value { value: ConstVal::Integral(ConstInt::Usize(val)) },
Err(_) => bug!("usize literal out of range for target"),
}
}
pub fn bool_ty(&mut self) -> Ty<'tcx> {
self.tcx.types.bool
}
pub fn unit_ty(&mut self) -> Ty<'tcx> {
self.tcx.mk_nil()
}
pub fn str_literal(&mut self, value: InternedString) -> Literal<'tcx> {
Literal::Value { value: ConstVal::Str(value) }
}
pub fn true_literal(&mut self) -> Literal<'tcx> {
Literal::Value { value: ConstVal::Bool(true) }
}
pub fn false_literal(&mut self) -> Literal<'tcx> {
Literal::Value { value: ConstVal::Bool(false) }
}
pub fn const_eval_literal(&mut self, e: &hir::Expr) -> Literal<'tcx> {
let tcx = self.tcx.global_tcx();
match ConstContext::with_tables(tcx, self.tables()).eval(e) {
Ok(value) => Literal::Value { value: value },
Err(s) => fatal_const_eval_err(tcx, &s, e.span, "expression")
}
}
pub fn trait_method(&mut self,
trait_def_id: DefId,
method_name: &str,
self_ty: Ty<'tcx>,
params: &[Ty<'tcx>])
-> (Ty<'tcx>, Literal<'tcx>) {
let method_name = Symbol::intern(method_name);
let substs = self.tcx.mk_substs_trait(self_ty, params);
for item in self.tcx.associated_items(trait_def_id) {
if item.kind == ty::AssociatedKind::Method && item.name == method_name {
let method_ty = self.tcx.item_type(item.def_id);
let method_ty = method_ty.subst(self.tcx, substs);
return (method_ty,
Literal::Item {
def_id: item.def_id,
substs: substs,
});
}
}
bug!("found no method `{}` in `{:?}`", method_name, trait_def_id);
}
pub fn num_variants(&mut self, adt_def: &ty::AdtDef) -> usize {
adt_def.variants.len()
}
pub fn all_fields(&mut self, adt_def: &ty::AdtDef, variant_index: usize) -> Vec<Field> {
(0..adt_def.variants[variant_index].fields.len())
.map(Field::new)
.collect()
}
pub fn needs_drop(&mut self, ty: Ty<'tcx>) -> bool {
let ty = self.tcx.lift_to_global(&ty).unwrap_or_else(|| {
bug!("MIR: Cx::needs_drop({}) got \
type with inference types/regions",
ty);
});
self.tcx.type_needs_drop_given_env(ty, &self.infcx.parameter_environment)
}
pub fn tcx(&self) -> TyCtxt<'a, 'gcx, 'tcx> {
self.tcx
}
pub fn tables(&self) -> &'a ty::TypeckTables<'gcx> {
self.infcx.tables.expect_interned()
}
pub fn check_overflow(&self) -> bool {
self.check_overflow
}
}
mod block;
mod expr;
mod to_ref;