1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
11 //! An experimental pass that scources for `#[rustc_mir]` attributes,
12 //! builds the resulting MIR, and dumps it out into a file for inspection.
14 //! The attribute formats that are currently accepted are:
16 //! - `#[rustc_mir(graphviz="file.gv")]`
17 //! - `#[rustc_mir(pretty="file.mir")]`
21 extern crate rustc_front;
26 use hair::cx::{PatNode, Cx};
29 use self::rustc::middle::infer;
30 use self::rustc::middle::region::CodeExtentData;
31 use self::rustc::middle::ty::{self, Ty};
32 use self::rustc::util::common::ErrorReported;
33 use self::rustc::util::nodemap::NodeMap;
34 use self::rustc_front::hir;
35 use self::rustc_front::visit;
36 use self::syntax::ast;
37 use self::syntax::attr::AttrMetaMethods;
38 use self::syntax::codemap::Span;
40 pub type MirMap<'tcx> = NodeMap<Mir<'tcx>>;
42 pub fn build_mir_for_crate<'tcx>(tcx: &ty::ctxt<'tcx>) -> MirMap<'tcx> {
43 let mut map = NodeMap();
45 let mut dump = OuterDump {
49 visit::walk_crate(&mut dump, tcx.map.krate());
54 ///////////////////////////////////////////////////////////////////////////
55 // OuterDump -- walks a crate, looking for fn items and methods to build MIR from
57 struct OuterDump<'a, 'tcx: 'a> {
58 tcx: &'a ty::ctxt<'tcx>,
59 map: &'a mut MirMap<'tcx>,
62 impl<'a, 'tcx> OuterDump<'a, 'tcx> {
63 fn visit_mir<OP>(&mut self, attributes: &'a [ast::Attribute], mut walk_op: OP)
64 where OP: for<'m> FnMut(&mut InnerDump<'a, 'm, 'tcx>)
66 let mut closure_dump = InnerDump {
71 for attr in attributes {
72 if attr.check_name("rustc_mir") {
73 closure_dump.attr = Some(attr);
76 walk_op(&mut closure_dump);
81 impl<'a, 'tcx> visit::Visitor<'tcx> for OuterDump<'a, 'tcx> {
82 fn visit_item(&mut self, item: &'tcx hir::Item) {
83 self.visit_mir(&item.attrs, |c| visit::walk_item(c, item));
84 visit::walk_item(self, item);
87 fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
88 match trait_item.node {
89 hir::MethodTraitItem(_, Some(_)) => {
90 self.visit_mir(&trait_item.attrs, |c| visit::walk_trait_item(c, trait_item));
92 hir::MethodTraitItem(_, None) |
93 hir::ConstTraitItem(..) |
94 hir::TypeTraitItem(..) => {}
96 visit::walk_trait_item(self, trait_item);
99 fn visit_impl_item(&mut self, impl_item: &'tcx hir::ImplItem) {
100 match impl_item.node {
101 hir::MethodImplItem(..) => {
102 self.visit_mir(&impl_item.attrs, |c| visit::walk_impl_item(c, impl_item));
104 hir::ConstImplItem(..) | hir::TypeImplItem(..) => {}
106 visit::walk_impl_item(self, impl_item);
110 ///////////////////////////////////////////////////////////////////////////
111 // InnerDump -- dumps MIR for a single fn and its contained closures
113 struct InnerDump<'a, 'm, 'tcx: 'a + 'm> {
114 tcx: &'a ty::ctxt<'tcx>,
115 map: &'m mut MirMap<'tcx>,
116 attr: Option<&'a ast::Attribute>,
119 impl<'a, 'm, 'tcx> visit::Visitor<'tcx> for InnerDump<'a,'m,'tcx> {
120 fn visit_item(&mut self, _: &'tcx hir::Item) {
121 // ignore nested items; they need their own graphviz annotation
124 fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem) {
125 // ignore nested items; they need their own graphviz annotation
128 fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem) {
129 // ignore nested items; they need their own graphviz annotation
132 fn visit_fn(&mut self,
133 fk: visit::FnKind<'tcx>,
134 decl: &'tcx hir::FnDecl,
135 body: &'tcx hir::Block,
138 let (prefix, implicit_arg_tys) = match fk {
139 visit::FnKind::Closure =>
140 (format!("{}-", id), vec![closure_self_ty(&self.tcx, id, body.id)]),
142 (format!(""), vec![]),
145 let param_env = ty::ParameterEnvironment::for_item(self.tcx, id);
147 let infcx = infer::new_infer_ctxt(self.tcx, &self.tcx.tables, Some(param_env), true);
149 match build_mir(Cx::new(&infcx), implicit_arg_tys, id, span, decl, body) {
151 let meta_item_list = self.attr
153 .flat_map(|a| a.meta_item_list())
154 .flat_map(|l| l.iter());
155 for item in meta_item_list {
156 if item.check_name("graphviz") {
157 match item.value_str() {
160 File::create(format!("{}{}", prefix, s))
161 .and_then(|ref mut output| dot::render(&mir, output))
165 self.tcx.sess.span_fatal(
167 &format!("Error writing graphviz \
168 results to `{}`: {}",
174 self.tcx.sess.span_err(
176 "graphviz attribute requires a path");
182 let previous = self.map.insert(id, mir);
183 assert!(previous.is_none());
185 Err(ErrorReported) => {}
188 visit::walk_fn(self, fk, decl, body, span);
192 fn build_mir<'a,'tcx:'a>(cx: Cx<'a,'tcx>,
193 implicit_arg_tys: Vec<Ty<'tcx>>,
196 decl: &'tcx hir::FnDecl,
197 body: &'tcx hir::Block)
198 -> Result<Mir<'tcx>, ErrorReported> {
199 // fetch the fully liberated fn signature (that is, all bound
200 // types/lifetimes replaced)
201 let fn_sig = match cx.tcx().tables.borrow().liberated_fn_sigs.get(&fn_id) {
202 Some(f) => f.clone(),
204 cx.tcx().sess.span_bug(span,
205 &format!("no liberated fn sig for {:?}", fn_id));
213 .map(|(index, arg)| {
214 (fn_sig.inputs[index], PatNode::irrefutable(&arg.pat))
218 let parameter_scope =
219 cx.tcx().region_maps.lookup_code_extent(
220 CodeExtentData::ParameterScope { fn_id: fn_id, body_id: body.id });
221 Ok(build::construct(cx,
230 fn closure_self_ty<'a, 'tcx>(tcx: &ty::ctxt<'tcx>,
231 closure_expr_id: ast::NodeId,
232 body_id: ast::NodeId)
234 let closure_ty = tcx.node_id_to_type(closure_expr_id);
236 // We're just hard-coding the idea that the signature will be
237 // &self or &mut self and hence will have a bound region with
239 let region = ty::Region::ReFree(ty::FreeRegion {
240 scope: tcx.region_maps.item_extent(body_id),
241 bound_region: ty::BoundRegion::BrAnon(0),
243 let region = tcx.mk_region(region);
245 match tcx.closure_kind(tcx.map.local_def_id(closure_expr_id)) {
246 ty::ClosureKind::FnClosureKind =>
248 ty::TypeAndMut { ty: closure_ty,
249 mutbl: hir::MutImmutable }),
250 ty::ClosureKind::FnMutClosureKind =>
252 ty::TypeAndMut { ty: closure_ty,
253 mutbl: hir::MutMutable }),
254 ty::ClosureKind::FnOnceClosureKind =>