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use self::ResolveReason::*;
use check::FnCtxt;
use rustc::ty::{self, Ty, TyCtxt, MethodCall, MethodCallee};
use rustc::ty::adjustment;
use rustc::ty::fold::{TypeFolder,TypeFoldable};
use rustc::infer::{InferCtxt, FixupError};
use rustc::util::nodemap::{DefIdMap, DefIdSet};
use std::mem;
use syntax::ast;
use syntax_pos::Span;
use rustc::hir::intravisit::{self, Visitor, NestedVisitorMap};
use rustc::hir;
impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
pub fn resolve_type_vars_in_body(&self, body: &'gcx hir::Body)
-> &'gcx ty::TypeckTables<'gcx> {
let item_id = self.tcx.hir.body_owner(body.id());
let item_def_id = self.tcx.hir.local_def_id(item_id);
let mut wbcx = WritebackCx::new(self);
for arg in &body.arguments {
wbcx.visit_node_id(ResolvingPattern(arg.pat.span), arg.id);
}
wbcx.visit_body(body);
wbcx.visit_upvar_borrow_map();
wbcx.visit_closures();
wbcx.visit_liberated_fn_sigs();
wbcx.visit_fru_field_types();
wbcx.visit_anon_types();
wbcx.visit_type_nodes();
wbcx.visit_cast_types();
wbcx.visit_lints();
wbcx.visit_free_region_map();
let used_trait_imports = mem::replace(&mut self.tables.borrow_mut().used_trait_imports,
DefIdSet());
debug!("used_trait_imports({:?}) = {:?}", item_def_id, used_trait_imports);
wbcx.tables.used_trait_imports = used_trait_imports;
wbcx.tables.tainted_by_errors = self.is_tainted_by_errors();
self.tcx.alloc_tables(wbcx.tables)
}
}
struct WritebackCx<'cx, 'gcx: 'cx+'tcx, 'tcx: 'cx> {
fcx: &'cx FnCtxt<'cx, 'gcx, 'tcx>,
tables: ty::TypeckTables<'gcx>,
free_to_bound_regions: DefIdMap<&'gcx ty::Region>
}
impl<'cx, 'gcx, 'tcx> WritebackCx<'cx, 'gcx, 'tcx> {
fn new(fcx: &'cx FnCtxt<'cx, 'gcx, 'tcx>) -> WritebackCx<'cx, 'gcx, 'tcx> {
let mut wbcx = WritebackCx {
fcx: fcx,
tables: ty::TypeckTables::empty(),
free_to_bound_regions: DefIdMap()
};
if fcx.anon_types.borrow().is_empty() {
return wbcx;
}
let gcx = fcx.tcx.global_tcx();
let free_substs = fcx.parameter_environment.free_substs;
for (i, k) in free_substs.iter().enumerate() {
let r = if let Some(r) = k.as_region() {
r
} else {
continue;
};
match *r {
ty::ReFree(ty::FreeRegion {
bound_region: ty::BoundRegion::BrNamed(def_id, name), ..
}) => {
let bound_region = gcx.mk_region(ty::ReEarlyBound(ty::EarlyBoundRegion {
index: i as u32,
name: name,
}));
wbcx.free_to_bound_regions.insert(def_id, bound_region);
}
_ => {
bug!("{:?} is not a free region for an early-bound lifetime", r);
}
}
}
wbcx
}
fn tcx(&self) -> TyCtxt<'cx, 'gcx, 'tcx> {
self.fcx.tcx
}
fn write_ty_to_tables(&mut self, node_id: ast::NodeId, ty: Ty<'gcx>) {
debug!("write_ty_to_tables({}, {:?})", node_id, ty);
assert!(!ty.needs_infer());
self.tables.node_types.insert(node_id, ty);
}
fn fix_scalar_builtin_expr(&mut self, e: &hir::Expr) {
match e.node {
hir::ExprUnary(hir::UnNeg, ref inner) |
hir::ExprUnary(hir::UnNot, ref inner) => {
let inner_ty = self.fcx.node_ty(inner.id);
let inner_ty = self.fcx.resolve_type_vars_if_possible(&inner_ty);
if inner_ty.is_scalar() {
self.fcx.tables.borrow_mut().method_map.remove(&MethodCall::expr(e.id));
}
}
hir::ExprBinary(ref op, ref lhs, ref rhs) |
hir::ExprAssignOp(ref op, ref lhs, ref rhs) => {
let lhs_ty = self.fcx.node_ty(lhs.id);
let lhs_ty = self.fcx.resolve_type_vars_if_possible(&lhs_ty);
let rhs_ty = self.fcx.node_ty(rhs.id);
let rhs_ty = self.fcx.resolve_type_vars_if_possible(&rhs_ty);
if lhs_ty.is_scalar() && rhs_ty.is_scalar() {
self.fcx.tables.borrow_mut().method_map.remove(&MethodCall::expr(e.id));
match e.node {
hir::ExprBinary(..) => {
if !op.node.is_by_value() {
self.fcx.tables.borrow_mut().adjustments.remove(&lhs.id);
}
},
hir::ExprAssignOp(..) => {
self.fcx.tables.borrow_mut().adjustments.remove(&lhs.id);
},
_ => {},
}
}
}
_ => {},
}
}
}
impl<'cx, 'gcx, 'tcx> Visitor<'gcx> for WritebackCx<'cx, 'gcx, 'tcx> {
fn nested_visit_map<'this>(&'this mut self) -> NestedVisitorMap<'this, 'gcx> {
NestedVisitorMap::None
}
fn visit_stmt(&mut self, s: &'gcx hir::Stmt) {
self.visit_node_id(ResolvingExpr(s.span), s.node.id());
intravisit::walk_stmt(self, s);
}
fn visit_expr(&mut self, e: &'gcx hir::Expr) {
self.fix_scalar_builtin_expr(e);
self.visit_node_id(ResolvingExpr(e.span), e.id);
self.visit_method_map_entry(ResolvingExpr(e.span),
MethodCall::expr(e.id));
if let hir::ExprClosure(_, _, body, _) = e.node {
let body = self.fcx.tcx.hir.body(body);
for arg in &body.arguments {
self.visit_node_id(ResolvingExpr(e.span), arg.id);
}
self.visit_body(body);
}
intravisit::walk_expr(self, e);
}
fn visit_block(&mut self, b: &'gcx hir::Block) {
self.visit_node_id(ResolvingExpr(b.span), b.id);
intravisit::walk_block(self, b);
}
fn visit_pat(&mut self, p: &'gcx hir::Pat) {
self.visit_node_id(ResolvingPattern(p.span), p.id);
intravisit::walk_pat(self, p);
}
fn visit_local(&mut self, l: &'gcx hir::Local) {
let var_ty = self.fcx.local_ty(l.span, l.id);
let var_ty = self.resolve(&var_ty, ResolvingLocal(l.span));
self.write_ty_to_tables(l.id, var_ty);
intravisit::walk_local(self, l);
}
}
impl<'cx, 'gcx, 'tcx> WritebackCx<'cx, 'gcx, 'tcx> {
fn visit_upvar_borrow_map(&mut self) {
for (upvar_id, upvar_capture) in self.fcx.tables.borrow().upvar_capture_map.iter() {
let new_upvar_capture = match *upvar_capture {
ty::UpvarCapture::ByValue => ty::UpvarCapture::ByValue,
ty::UpvarCapture::ByRef(ref upvar_borrow) => {
let r = upvar_borrow.region;
let r = self.resolve(&r, ResolvingUpvar(*upvar_id));
ty::UpvarCapture::ByRef(
ty::UpvarBorrow { kind: upvar_borrow.kind, region: r })
}
};
debug!("Upvar capture for {:?} resolved to {:?}",
upvar_id,
new_upvar_capture);
self.tables.upvar_capture_map.insert(*upvar_id, new_upvar_capture);
}
}
fn visit_closures(&mut self) {
for (&id, closure_ty) in self.fcx.tables.borrow().closure_tys.iter() {
let closure_ty = self.resolve(closure_ty, ResolvingClosure(id));
self.tables.closure_tys.insert(id, closure_ty);
}
for (&id, &closure_kind) in self.fcx.tables.borrow().closure_kinds.iter() {
self.tables.closure_kinds.insert(id, closure_kind);
}
}
fn visit_cast_types(&mut self) {
self.tables.cast_kinds.extend(
self.fcx.tables.borrow().cast_kinds.iter().map(|(&key, &value)| (key, value)));
}
fn visit_lints(&mut self) {
self.fcx.tables.borrow_mut().lints.transfer(&mut self.tables.lints);
}
fn visit_free_region_map(&mut self) {
self.tables.free_region_map = self.fcx.tables.borrow().free_region_map.clone();
}
fn visit_anon_types(&mut self) {
let gcx = self.tcx().global_tcx();
for (&node_id, &concrete_ty) in self.fcx.anon_types.borrow().iter() {
let reason = ResolvingAnonTy(node_id);
let inside_ty = self.resolve(&concrete_ty, reason);
let outside_ty = gcx.fold_regions(&inside_ty, &mut false, |r, _| {
match *r {
ty::ReStatic |
ty::ReEmpty => gcx.mk_region(*r),
ty::ReFree(ty::FreeRegion {
bound_region: ty::BoundRegion::BrNamed(def_id, ..), ..
}) if self.free_to_bound_regions.contains_key(&def_id) => {
self.free_to_bound_regions[&def_id]
}
ty::ReFree(_) |
ty::ReEarlyBound(_) |
ty::ReLateBound(..) |
ty::ReScope(_) |
ty::ReSkolemized(..) => {
let span = reason.span(self.tcx());
span_err!(self.tcx().sess, span, E0564,
"only named lifetimes are allowed in `impl Trait`, \
but `{}` was found in the type `{}`", r, inside_ty);
gcx.mk_region(ty::ReStatic)
}
ty::ReVar(_) |
ty::ReErased => {
let span = reason.span(self.tcx());
span_bug!(span, "invalid region in impl Trait: {:?}", r);
}
}
});
self.tables.node_types.insert(node_id, outside_ty);
}
}
fn visit_node_id(&mut self, reason: ResolveReason, id: ast::NodeId) {
if let Some(def) = self.fcx.tables.borrow_mut().type_relative_path_defs.remove(&id) {
self.tables.type_relative_path_defs.insert(id, def);
}
self.visit_adjustments(reason, id);
let n_ty = self.fcx.node_ty(id);
let n_ty = self.resolve(&n_ty, reason);
self.write_ty_to_tables(id, n_ty);
debug!("Node {} has type {:?}", id, n_ty);
self.fcx.opt_node_ty_substs(id, |item_substs| {
let item_substs = self.resolve(item_substs, reason);
if !item_substs.is_noop() {
debug!("write_substs_to_tcx({}, {:?})", id, item_substs);
assert!(!item_substs.substs.needs_infer());
self.tables.item_substs.insert(id, item_substs);
}
});
}
fn visit_adjustments(&mut self, reason: ResolveReason, id: ast::NodeId) {
let adjustments = self.fcx.tables.borrow_mut().adjustments.remove(&id);
match adjustments {
None => {
debug!("No adjustments for node {}", id);
}
Some(adjustment) => {
let resolved_adjustment = match adjustment.kind {
adjustment::Adjust::NeverToAny => {
adjustment::Adjust::NeverToAny
}
adjustment::Adjust::ReifyFnPointer => {
adjustment::Adjust::ReifyFnPointer
}
adjustment::Adjust::MutToConstPointer => {
adjustment::Adjust::MutToConstPointer
}
adjustment::Adjust::ClosureFnPointer => {
adjustment::Adjust::ClosureFnPointer
}
adjustment::Adjust::UnsafeFnPointer => {
adjustment::Adjust::UnsafeFnPointer
}
adjustment::Adjust::DerefRef { autoderefs, autoref, unsize } => {
for autoderef in 0..autoderefs {
let method_call = MethodCall::autoderef(id, autoderef as u32);
self.visit_method_map_entry(reason, method_call);
}
adjustment::Adjust::DerefRef {
autoderefs: autoderefs,
autoref: self.resolve(&autoref, reason),
unsize: unsize,
}
}
};
let resolved_adjustment = adjustment::Adjustment {
kind: resolved_adjustment,
target: self.resolve(&adjustment.target, reason)
};
debug!("Adjustments for node {}: {:?}", id, resolved_adjustment);
self.tables.adjustments.insert(id, resolved_adjustment);
}
}
}
fn visit_method_map_entry(&mut self,
reason: ResolveReason,
method_call: MethodCall) {
let new_method = match self.fcx.tables.borrow_mut().method_map.remove(&method_call) {
Some(method) => {
debug!("writeback::resolve_method_map_entry(call={:?}, entry={:?})",
method_call,
method);
let new_method = MethodCallee {
def_id: method.def_id,
ty: self.resolve(&method.ty, reason),
substs: self.resolve(&method.substs, reason),
};
Some(new_method)
}
None => None
};
if let Some(method) = new_method {
self.tables.method_map.insert(method_call, method);
}
}
fn visit_liberated_fn_sigs(&mut self) {
for (&node_id, fn_sig) in self.fcx.tables.borrow().liberated_fn_sigs.iter() {
let fn_sig = self.resolve(fn_sig, ResolvingFnSig(node_id));
self.tables.liberated_fn_sigs.insert(node_id, fn_sig.clone());
}
}
fn visit_fru_field_types(&mut self) {
for (&node_id, ftys) in self.fcx.tables.borrow().fru_field_types.iter() {
let ftys = self.resolve(ftys, ResolvingFieldTypes(node_id));
self.tables.fru_field_types.insert(node_id, ftys);
}
}
fn visit_type_nodes(&self) {
for (&id, ty) in self.fcx.ast_ty_to_ty_cache.borrow().iter() {
let ty = self.resolve(ty, ResolvingTyNode(id));
self.fcx.tcx.ast_ty_to_ty_cache.borrow_mut().insert(id, ty);
}
}
fn resolve<T>(&self, x: &T, reason: ResolveReason) -> T::Lifted
where T: TypeFoldable<'tcx> + ty::Lift<'gcx>
{
let x = x.fold_with(&mut Resolver::new(self.fcx, reason));
if let Some(lifted) = self.tcx().lift_to_global(&x) {
lifted
} else {
span_bug!(reason.span(self.tcx()),
"writeback: `{:?}` missing from the global type context", x);
}
}
}
#[derive(Copy, Clone, Debug)]
enum ResolveReason {
ResolvingExpr(Span),
ResolvingLocal(Span),
ResolvingPattern(Span),
ResolvingUpvar(ty::UpvarId),
ResolvingClosure(ast::NodeId),
ResolvingFnSig(ast::NodeId),
ResolvingFieldTypes(ast::NodeId),
ResolvingAnonTy(ast::NodeId),
ResolvingTyNode(ast::NodeId),
}
impl<'a, 'gcx, 'tcx> ResolveReason {
fn span(&self, tcx: TyCtxt<'a, 'gcx, 'tcx>) -> Span {
match *self {
ResolvingExpr(s) => s,
ResolvingLocal(s) => s,
ResolvingPattern(s) => s,
ResolvingUpvar(upvar_id) => {
tcx.expr_span(upvar_id.closure_expr_id)
}
ResolvingClosure(id) |
ResolvingFnSig(id) |
ResolvingFieldTypes(id) |
ResolvingTyNode(id) |
ResolvingAnonTy(id) => {
tcx.hir.span(id)
}
}
}
}
struct Resolver<'cx, 'gcx: 'cx+'tcx, 'tcx: 'cx> {
tcx: TyCtxt<'cx, 'gcx, 'tcx>,
infcx: &'cx InferCtxt<'cx, 'gcx, 'tcx>,
reason: ResolveReason,
}
impl<'cx, 'gcx, 'tcx> Resolver<'cx, 'gcx, 'tcx> {
fn new(fcx: &'cx FnCtxt<'cx, 'gcx, 'tcx>,
reason: ResolveReason)
-> Resolver<'cx, 'gcx, 'tcx>
{
Resolver::from_infcx(fcx, reason)
}
fn from_infcx(infcx: &'cx InferCtxt<'cx, 'gcx, 'tcx>,
reason: ResolveReason)
-> Resolver<'cx, 'gcx, 'tcx>
{
Resolver { infcx: infcx,
tcx: infcx.tcx,
reason: reason }
}
fn report_error(&self, e: FixupError) {
if !self.tcx.sess.has_errors() {
match self.reason {
ResolvingExpr(span) => {
struct_span_err!(
self.tcx.sess, span, E0101,
"cannot determine a type for this expression: {}", e)
.span_label(span, &format!("cannot resolve type of expression"))
.emit();
}
ResolvingLocal(span) => {
struct_span_err!(
self.tcx.sess, span, E0102,
"cannot determine a type for this local variable: {}", e)
.span_label(span, &format!("cannot resolve type of variable"))
.emit();
}
ResolvingPattern(span) => {
span_err!(self.tcx.sess, span, E0103,
"cannot determine a type for this pattern binding: {}", e);
}
ResolvingUpvar(upvar_id) => {
let span = self.reason.span(self.tcx);
span_err!(self.tcx.sess, span, E0104,
"cannot resolve lifetime for captured variable `{}`: {}",
self.tcx.local_var_name_str(upvar_id.var_id), e);
}
ResolvingClosure(_) => {
let span = self.reason.span(self.tcx);
span_err!(self.tcx.sess, span, E0196,
"cannot determine a type for this closure")
}
ResolvingFnSig(_) |
ResolvingFieldTypes(_) |
ResolvingTyNode(_) => {
let span = self.reason.span(self.tcx);
self.tcx.sess.delay_span_bug(
span,
&format!("cannot resolve some aspect of data for {:?}: {}",
self.reason, e));
}
ResolvingAnonTy(_) => {
let span = self.reason.span(self.tcx);
span_err!(self.tcx.sess, span, E0563,
"cannot determine a type for this `impl Trait`: {}", e)
}
}
}
}
}
impl<'cx, 'gcx, 'tcx> TypeFolder<'gcx, 'tcx> for Resolver<'cx, 'gcx, 'tcx> {
fn tcx<'a>(&'a self) -> TyCtxt<'a, 'gcx, 'tcx> {
self.tcx
}
fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
match self.infcx.fully_resolve(&t) {
Ok(t) => t,
Err(e) => {
debug!("Resolver::fold_ty: input type `{:?}` not fully resolvable",
t);
self.report_error(e);
self.tcx().types.err
}
}
}
fn fold_region(&mut self, r: &'tcx ty::Region) -> &'tcx ty::Region {
match self.infcx.fully_resolve(&r) {
Ok(r) => r,
Err(e) => {
self.report_error(e);
self.tcx.mk_region(ty::ReStatic)
}
}
}
}