--- /dev/null
+// Copyright 2012-2015 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.
+
+//! This pass is only used for the UNIT TESTS and DEBUGGING NEEDS
+//! around dependency graph construction. It serves two purposes; it
+//! will dump graphs in graphviz form to disk, and it searches for
+//! `#[rustc_if_this_changed]` and `#[rustc_then_this_would_need]`
+//! annotations. These annotations can be used to test whether paths
+//! exist in the graph. We report errors on each
+//! `rustc_if_this_changed` annotation. If a path exists in all
+//! cases, then we would report "all path(s) exist". Otherwise, we
+//! report: "no path to `foo`" for each case where no path exists.
+//! `compile-fail` tests can then be used to check when paths exist or
+//! do not.
+//!
+//! The full form of the `rustc_if_this_changed` annotation is
+//! `#[rustc_if_this_changed(id)]`. The `"id"` is optional and
+//! defaults to `"id"` if omitted.
+//!
+//! Example:
+//!
+//! ```
+//! #[rustc_if_this_changed]
+//! fn foo() { }
+//!
+//! #[rustc_then_this_would_need("trans")] //~ ERROR no path from `foo`
+//! fn bar() { }
+//!
+//! #[rustc_then_this_would_need("trans")] //~ ERROR OK
+//! fn baz() { foo(); }
+//! ```
+
+use graphviz as dot;
+use rustc::dep_graph::{DepGraphQuery, DepNode};
+use rustc::middle::def_id::DefId;
+use rustc::middle::ty;
+use rustc_data_structures::fnv::{FnvHashMap, FnvHashSet};
+use rustc_data_structures::graph::{Direction, INCOMING, OUTGOING, NodeIndex};
+use rustc_front::hir;
+use rustc_front::intravisit::Visitor;
+use std::borrow::IntoCow;
+use std::env;
+use std::fs::File;
+use std::io::Write;
+use syntax::ast;
+use syntax::attr::AttrMetaMethods;
+use syntax::codemap::Span;
+use syntax::parse::token::InternedString;
+
+const IF_THIS_CHANGED: &'static str = "rustc_if_this_changed";
+const THEN_THIS_WOULD_NEED: &'static str = "rustc_then_this_would_need";
+const ID: &'static str = "id";
+
+pub fn assert_dep_graph(tcx: &ty::ctxt) {
+ let _ignore = tcx.dep_graph.in_ignore();
+
+ if tcx.sess.opts.dump_dep_graph {
+ dump_graph(tcx);
+ }
+
+ // Find annotations supplied by user (if any).
+ let (if_this_changed, then_this_would_need) = {
+ let mut visitor = IfThisChanged { tcx: tcx,
+ if_this_changed: FnvHashMap(),
+ then_this_would_need: FnvHashMap() };
+ tcx.map.krate().visit_all_items(&mut visitor);
+ (visitor.if_this_changed, visitor.then_this_would_need)
+ };
+
+ // Check paths.
+ check_paths(tcx, &if_this_changed, &then_this_would_need);
+}
+
+type SourceHashMap = FnvHashMap<InternedString,
+ FnvHashSet<(Span, DefId, DepNode)>>;
+type TargetHashMap = FnvHashMap<InternedString,
+ FnvHashSet<(Span, InternedString, ast::NodeId, DepNode)>>;
+
+struct IfThisChanged<'a, 'tcx:'a> {
+ tcx: &'a ty::ctxt<'tcx>,
+ if_this_changed: SourceHashMap,
+ then_this_would_need: TargetHashMap,
+}
+
+impl<'a, 'tcx> IfThisChanged<'a, 'tcx> {
+ fn process_attrs(&mut self, node_id: ast::NodeId, def_id: DefId) {
+ for attr in self.tcx.get_attrs(def_id).iter() {
+ if attr.check_name(IF_THIS_CHANGED) {
+ let mut id = None;
+ for meta_item in attr.meta_item_list().unwrap_or_default() {
+ match meta_item.node {
+ ast::MetaWord(ref s) if id.is_none() => id = Some(s.clone()),
+ _ => {
+ self.tcx.sess.span_err(
+ meta_item.span,
+ &format!("unexpected meta-item {:?}", meta_item.node));
+ }
+ }
+ }
+ let id = id.unwrap_or(InternedString::new(ID));
+ self.if_this_changed.entry(id)
+ .or_insert(FnvHashSet())
+ .insert((attr.span, def_id, DepNode::Hir(def_id)));
+ } else if attr.check_name(THEN_THIS_WOULD_NEED) {
+ let mut dep_node_interned = None;
+ let mut id = None;
+ for meta_item in attr.meta_item_list().unwrap_or_default() {
+ match meta_item.node {
+ ast::MetaWord(ref s) if dep_node_interned.is_none() =>
+ dep_node_interned = Some(s.clone()),
+ ast::MetaWord(ref s) if id.is_none() =>
+ id = Some(s.clone()),
+ _ => {
+ self.tcx.sess.span_err(
+ meta_item.span,
+ &format!("unexpected meta-item {:?}", meta_item.node));
+ }
+ }
+ }
+ let dep_node_str = dep_node_interned.as_ref().map(|s| &**s);
+ macro_rules! match_depnode_name {
+ ($input:expr, $def_id:expr, match { $($variant:ident,)* } else $y:expr) => {
+ match $input {
+ $(Some(stringify!($variant)) => DepNode::$variant($def_id),)*
+ _ => $y
+ }
+ }
+ }
+ let dep_node = match_depnode_name! {
+ dep_node_str, def_id, match {
+ CollectItem,
+ BorrowCheck,
+ TransCrateItem,
+ TypeckItemType,
+ TypeckItemBody,
+ ImplOrTraitItems,
+ ItemSignature,
+ FieldTy,
+ TraitItemDefIds,
+ InherentImpls,
+ ImplItems,
+ TraitImpls,
+ ReprHints,
+ } else {
+ self.tcx.sess.span_fatal(
+ attr.span,
+ &format!("unrecognized DepNode variant {:?}", dep_node_str));
+ }
+ };
+ let id = id.unwrap_or(InternedString::new(ID));
+ self.then_this_would_need
+ .entry(id)
+ .or_insert(FnvHashSet())
+ .insert((attr.span, dep_node_interned.clone().unwrap(), node_id, dep_node));
+ }
+ }
+ }
+}
+
+impl<'a, 'tcx> Visitor<'tcx> for IfThisChanged<'a, 'tcx> {
+ fn visit_item(&mut self, item: &'tcx hir::Item) {
+ let def_id = self.tcx.map.local_def_id(item.id);
+ self.process_attrs(item.id, def_id);
+ }
+}
+
+fn check_paths(tcx: &ty::ctxt,
+ if_this_changed: &SourceHashMap,
+ then_this_would_need: &TargetHashMap)
+{
+ // Return early here so as not to construct the query, which is not cheap.
+ if if_this_changed.is_empty() {
+ return;
+ }
+ let query = tcx.dep_graph.query();
+ for (id, sources) in if_this_changed {
+ let targets = match then_this_would_need.get(id) {
+ Some(targets) => targets,
+ None => {
+ for &(source_span, _, _) in sources.iter().take(1) {
+ tcx.sess.span_err(
+ source_span,
+ &format!("no targets for id `{}`", id));
+ }
+ continue;
+ }
+ };
+
+ for &(_, source_def_id, source_dep_node) in sources {
+ let dependents = query.dependents(source_dep_node);
+ for &(target_span, ref target_pass, _, ref target_dep_node) in targets {
+ if !dependents.contains(&target_dep_node) {
+ tcx.sess.span_err(
+ target_span,
+ &format!("no path from `{}` to `{}`",
+ tcx.item_path_str(source_def_id),
+ target_pass));
+ } else {
+ tcx.sess.span_err(
+ target_span,
+ &format!("OK"));
+ }
+ }
+ }
+ }
+}
+
+fn dump_graph(tcx: &ty::ctxt) {
+ let path: String = env::var("RUST_DEP_GRAPH").unwrap_or_else(|_| format!("dep_graph"));
+ let query = tcx.dep_graph.query();
+
+ let nodes = match env::var("RUST_DEP_GRAPH_FILTER") {
+ Ok(string) => {
+ // Expect one of: "-> target", "source -> target", or "source ->".
+ let parts: Vec<_> = string.split("->").collect();
+ if parts.len() > 2 {
+ panic!("Invalid RUST_DEP_GRAPH_FILTER: expected '[source] -> [target]'");
+ }
+ let sources = node_set(&query, &parts[0]);
+ let targets = node_set(&query, &parts[1]);
+ filter_nodes(&query, &sources, &targets)
+ }
+ Err(_) => {
+ query.nodes()
+ .into_iter()
+ .collect()
+ }
+ };
+ let edges = filter_edges(&query, &nodes);
+
+ { // dump a .txt file with just the edges:
+ let txt_path = format!("{}.txt", path);
+ let mut file = File::create(&txt_path).unwrap();
+ for &(source, target) in &edges {
+ write!(file, "{:?} -> {:?}\n", source, target).unwrap();
+ }
+ }
+
+ { // dump a .dot file in graphviz format:
+ let dot_path = format!("{}.dot", path);
+ let mut v = Vec::new();
+ dot::render(&GraphvizDepGraph(nodes, edges), &mut v).unwrap();
+ File::create(&dot_path).and_then(|mut f| f.write_all(&v)).unwrap();
+ }
+}
+
+pub struct GraphvizDepGraph(FnvHashSet<DepNode>, Vec<(DepNode, DepNode)>);
+
+impl<'a, 'tcx> dot::GraphWalk<'a, DepNode, (DepNode, DepNode)> for GraphvizDepGraph {
+ fn nodes(&self) -> dot::Nodes<DepNode> {
+ let nodes: Vec<_> = self.0.iter().cloned().collect();
+ nodes.into_cow()
+ }
+ fn edges(&self) -> dot::Edges<(DepNode, DepNode)> {
+ self.1[..].into_cow()
+ }
+ fn source(&self, edge: &(DepNode, DepNode)) -> DepNode {
+ edge.0
+ }
+ fn target(&self, edge: &(DepNode, DepNode)) -> DepNode {
+ edge.1
+ }
+}
+
+impl<'a, 'tcx> dot::Labeller<'a, DepNode, (DepNode, DepNode)> for GraphvizDepGraph {
+ fn graph_id(&self) -> dot::Id {
+ dot::Id::new("DependencyGraph").unwrap()
+ }
+ fn node_id(&self, n: &DepNode) -> dot::Id {
+ let s: String =
+ format!("{:?}", n).chars()
+ .map(|c| if c == '_' || c.is_alphanumeric() { c } else { '_' })
+ .collect();
+ debug!("n={:?} s={:?}", n, s);
+ dot::Id::new(s).unwrap()
+ }
+ fn node_label(&self, n: &DepNode) -> dot::LabelText {
+ dot::LabelText::label(format!("{:?}", n))
+ }
+}
+
+// Given an optional filter like `"x,y,z"`, returns either `None` (no
+// filter) or the set of nodes whose labels contain all of those
+// substrings.
+fn node_set(query: &DepGraphQuery, filter: &str) -> Option<FnvHashSet<DepNode>> {
+ debug!("node_set(filter={:?})", filter);
+
+ if filter.trim().is_empty() {
+ return None;
+ }
+
+ let filters: Vec<&str> = filter.split("&").map(|s| s.trim()).collect();
+
+ debug!("node_set: filters={:?}", filters);
+
+ Some(query.nodes()
+ .into_iter()
+ .filter(|n| {
+ let s = format!("{:?}", n);
+ filters.iter().all(|f| s.contains(f))
+ })
+ .collect())
+}
+
+fn filter_nodes(query: &DepGraphQuery,
+ sources: &Option<FnvHashSet<DepNode>>,
+ targets: &Option<FnvHashSet<DepNode>>)
+ -> FnvHashSet<DepNode>
+{
+ if let &Some(ref sources) = sources {
+ if let &Some(ref targets) = targets {
+ walk_between(query, sources, targets)
+ } else {
+ walk_nodes(query, sources, OUTGOING)
+ }
+ } else if let &Some(ref targets) = targets {
+ walk_nodes(query, targets, INCOMING)
+ } else {
+ query.nodes().into_iter().collect()
+ }
+}
+
+fn walk_nodes(query: &DepGraphQuery,
+ starts: &FnvHashSet<DepNode>,
+ direction: Direction)
+ -> FnvHashSet<DepNode>
+{
+ let mut set = FnvHashSet();
+ for start in starts {
+ debug!("walk_nodes: start={:?} outgoing?={:?}", start, direction == OUTGOING);
+ if set.insert(*start) {
+ let mut stack = vec![query.indices[start]];
+ while let Some(index) = stack.pop() {
+ for (_, edge) in query.graph.adjacent_edges(index, direction) {
+ let neighbor_index = edge.source_or_target(direction);
+ let neighbor = query.graph.node_data(neighbor_index);
+ if set.insert(*neighbor) {
+ stack.push(neighbor_index);
+ }
+ }
+ }
+ }
+ }
+ set
+}
+
+fn walk_between(query: &DepGraphQuery,
+ sources: &FnvHashSet<DepNode>,
+ targets: &FnvHashSet<DepNode>)
+ -> FnvHashSet<DepNode>
+{
+ // This is a bit tricky. We want to include a node only if it is:
+ // (a) reachable from a source and (b) will reach a target. And we
+ // have to be careful about cycles etc. Luckily efficiency is not
+ // a big concern!
+
+ #[derive(Copy, Clone, PartialEq)]
+ enum State { Undecided, Deciding, Included, Excluded }
+
+ let mut node_states = vec![State::Undecided; query.graph.len_nodes()];
+
+ for &target in targets {
+ node_states[query.indices[&target].0] = State::Included;
+ }
+
+ for source in sources.iter().map(|n| query.indices[n]) {
+ recurse(query, &mut node_states, source);
+ }
+
+ return query.nodes()
+ .into_iter()
+ .filter(|n| {
+ let index = query.indices[n];
+ node_states[index.0] == State::Included
+ })
+ .collect();
+
+ fn recurse(query: &DepGraphQuery,
+ node_states: &mut [State],
+ node: NodeIndex)
+ -> bool
+ {
+ match node_states[node.0] {
+ // known to reach a target
+ State::Included => return true,
+
+ // known not to reach a target
+ State::Excluded => return false,
+
+ // backedge, not yet known, say false
+ State::Deciding => return false,
+
+ State::Undecided => { }
+ }
+
+ node_states[node.0] = State::Deciding;
+
+ for neighbor_index in query.graph.successor_nodes(node) {
+ if recurse(query, node_states, neighbor_index) {
+ node_states[node.0] = State::Included;
+ }
+ }
+
+ // if we didn't find a path to target, then set to excluded
+ if node_states[node.0] == State::Deciding {
+ node_states[node.0] = State::Excluded;
+ false
+ } else {
+ assert!(node_states[node.0] == State::Included);
+ true
+ }
+ }
+}
+
+fn filter_edges(query: &DepGraphQuery,
+ nodes: &FnvHashSet<DepNode>)
+ -> Vec<(DepNode, DepNode)>
+{
+ query.edges()
+ .into_iter()
+ .filter(|&(source, target)| nodes.contains(&source) && nodes.contains(&target))
+ .collect()
+}
projects / rust.git / commitdiff