Rollup merge of #59251 - matthewjasper:fix-graphviz, r=petrochenkov

Use a valid name for graphviz graphs

Hiridification has broken graphviz output because `HirId` has a more complex display implemetation than `NodeId`. Since the id was just used to generate a distinct identifier, we just pull out the various constituent indexed.

10 files changed, 85 insertions, 40 deletions

diff --git a/src/librustc_driver/pretty.rs b/src/librustc_driver/pretty.rs
index dde88a21240..ace5198deaf 100644
--- a/src/librustc_driver/pretty.rs
+++ b/src/librustc_driver/pretty.rs
@@ -633,10 +633,20 @@ fn print_flowgraph<'a, 'tcx, W: Write>(variants: Vec<borrowck_dot::Variant>,
     let body = tcx.hir().body(body_id);
     let cfg = cfg::CFG::new(tcx, &body);
     let labelled_edges = mode != PpFlowGraphMode::UnlabelledEdges;
+    let hir_id = code.id();
+    // We have to disassemble the hir_id because name must be ASCII
+    // alphanumeric. This does not appear in the rendered graph, so it does not
+    // have to be user friendly.
+    let name = format!(
+        "hir_id_{}_{}_{}",
+        hir_id.owner.address_space().index(),
+        hir_id.owner.as_array_index(),
+        hir_id.local_id.index(),
+    );
     let lcfg = LabelledCFG {
         tcx,
         cfg: &cfg,
-        name: format!("node_{}", code.id()),
+        name,
         labelled_edges,
     };
 
diff --git a/src/librustc_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs
index c4e371d5afe..551f18b95fe 100644
--- a/src/librustc_mir/borrow_check/mod.rs
+++ b/src/librustc_mir/borrow_check/mod.rs
@@ -156,7 +156,7 @@ fn do_mir_borrowck<'a, 'gcx, 'tcx>(
     let mut flow_inits = FlowAtLocation::new(do_dataflow(
         tcx,
         mir,
-        id,
+        def_id,
         &attributes,
         &dead_unwinds,
         MaybeInitializedPlaces::new(tcx, mir, &mdpe),
@@ -191,7 +191,7 @@ fn do_mir_borrowck<'a, 'gcx, 'tcx>(
     let flow_borrows = FlowAtLocation::new(do_dataflow(
         tcx,
         mir,
-        id,
+        def_id,
         &attributes,
         &dead_unwinds,
         Borrows::new(tcx, mir, regioncx.clone(), &borrow_set),
@@ -200,7 +200,7 @@ fn do_mir_borrowck<'a, 'gcx, 'tcx>(
     let flow_uninits = FlowAtLocation::new(do_dataflow(
         tcx,
         mir,
-        id,
+        def_id,
         &attributes,
         &dead_unwinds,
         MaybeUninitializedPlaces::new(tcx, mir, &mdpe),
@@ -209,7 +209,7 @@ fn do_mir_borrowck<'a, 'gcx, 'tcx>(
     let flow_ever_inits = FlowAtLocation::new(do_dataflow(
         tcx,
         mir,
-        id,
+        def_id,
         &attributes,
         &dead_unwinds,
         EverInitializedPlaces::new(tcx, mir, &mdpe),
diff --git a/src/librustc_mir/dataflow/graphviz.rs b/src/librustc_mir/dataflow/graphviz.rs
index da9cc118f55..d68377681f1 100644
--- a/src/librustc_mir/dataflow/graphviz.rs
+++ b/src/librustc_mir/dataflow/graphviz.rs
@@ -1,6 +1,6 @@
 //! Hook into libgraphviz for rendering dataflow graphs for MIR.
 
-use rustc::hir::HirId;
+use rustc::hir::def_id::DefId;
 use rustc::mir::{BasicBlock, Mir};
 
 use std::fs;
@@ -8,13 +8,15 @@ use std::io;
 use std::marker::PhantomData;
 use std::path::Path;
 
+use crate::util::graphviz_safe_def_name;
+
 use super::{BitDenotation, DataflowState};
 use super::DataflowBuilder;
 use super::DebugFormatted;
 
 pub trait MirWithFlowState<'tcx> {
     type BD: BitDenotation<'tcx>;
-    fn hir_id(&self) -> HirId;
+    fn def_id(&self) -> DefId;
     fn mir(&self) -> &Mir<'tcx>;
     fn flow_state(&self) -> &DataflowState<'tcx, Self::BD>;
 }
@@ -23,7 +25,7 @@ impl<'a, 'tcx, BD> MirWithFlowState<'tcx> for DataflowBuilder<'a, 'tcx, BD>
     where BD: BitDenotation<'tcx>
 {
     type BD = BD;
-    fn hir_id(&self) -> HirId { self.hir_id }
+    fn def_id(&self) -> DefId { self.def_id }
     fn mir(&self) -> &Mir<'tcx> { self.flow_state.mir() }
     fn flow_state(&self) -> &DataflowState<'tcx, Self::BD> { &self.flow_state.flow_state }
 }
@@ -47,8 +49,8 @@ pub(crate) fn print_borrowck_graph_to<'a, 'tcx, BD, P>(
     let g = Graph { mbcx, phantom: PhantomData, render_idx };
     let mut v = Vec::new();
     dot::render(&g, &mut v)?;
-    debug!("print_borrowck_graph_to path: {} hir_id: {}",
-           path.display(), mbcx.hir_id);
+    debug!("print_borrowck_graph_to path: {} def_id: {:?}",
+           path.display(), mbcx.def_id);
     fs::write(path, v)
 }
 
@@ -69,9 +71,8 @@ impl<'a, 'tcx, MWF, P> dot::Labeller<'a> for Graph<'a, 'tcx, MWF, P>
     type Node = Node;
     type Edge = Edge;
     fn graph_id(&self) -> dot::Id<'_> {
-        dot::Id::new(format!("graph_for_node_{}",
-                             self.mbcx.hir_id()))
-            .unwrap()
+        let name = graphviz_safe_def_name(self.mbcx.def_id());
+        dot::Id::new(format!("graph_for_def_id_{}", name)).unwrap()
     }
 
     fn node_id(&self, n: &Node) -> dot::Id<'_> {
diff --git a/src/librustc_mir/dataflow/mod.rs b/src/librustc_mir/dataflow/mod.rs
index af2cd8f979a..af0e3f5a270 100644
--- a/src/librustc_mir/dataflow/mod.rs
+++ b/src/librustc_mir/dataflow/mod.rs
@@ -4,7 +4,7 @@ use rustc_data_structures::bit_set::{BitSet, BitSetOperator, HybridBitSet};
 use rustc_data_structures::indexed_vec::Idx;
 use rustc_data_structures::work_queue::WorkQueue;
 
-use rustc::hir::HirId;
+use rustc::hir::def_id::DefId;
 use rustc::ty::{self, TyCtxt};
 use rustc::mir::{self, Mir, BasicBlock, BasicBlockData, Location, Statement, Terminator};
 use rustc::mir::traversal;
@@ -39,7 +39,7 @@ pub(crate) struct DataflowBuilder<'a, 'tcx: 'a, BD>
 where
     BD: BitDenotation<'tcx>
 {
-    hir_id: HirId,
+    def_id: DefId,
     flow_state: DataflowAnalysis<'a, 'tcx, BD>,
     print_preflow_to: Option<String>,
     print_postflow_to: Option<String>,
@@ -117,7 +117,7 @@ pub struct MoveDataParamEnv<'gcx, 'tcx> {
 
 pub(crate) fn do_dataflow<'a, 'gcx, 'tcx, BD, P>(tcx: TyCtxt<'a, 'gcx, 'tcx>,
                                                  mir: &'a Mir<'tcx>,
-                                                 hir_id: HirId,
+                                                 def_id: DefId,
                                                  attributes: &[ast::Attribute],
                                                  dead_unwinds: &BitSet<BasicBlock>,
                                                  bd: BD,
@@ -127,14 +127,14 @@ pub(crate) fn do_dataflow<'a, 'gcx, 'tcx, BD, P>(tcx: TyCtxt<'a, 'gcx, 'tcx>,
           P: Fn(&BD, BD::Idx) -> DebugFormatted
 {
     let flow_state = DataflowAnalysis::new(mir, dead_unwinds, bd);
-    flow_state.run(tcx, hir_id, attributes, p)
+    flow_state.run(tcx, def_id, attributes, p)
 }
 
 impl<'a, 'gcx: 'tcx, 'tcx: 'a, BD> DataflowAnalysis<'a, 'tcx, BD> where BD: BitDenotation<'tcx>
 {
     pub(crate) fn run<P>(self,
                          tcx: TyCtxt<'a, 'gcx, 'tcx>,
-                         hir_id: HirId,
+                         def_id: DefId,
                          attributes: &[ast::Attribute],
                          p: P) -> DataflowResults<'tcx, BD>
         where P: Fn(&BD, BD::Idx) -> DebugFormatted
@@ -159,7 +159,7 @@ impl<'a, 'gcx: 'tcx, 'tcx: 'a, BD> DataflowAnalysis<'a, 'tcx, BD> where BD: BitD
             name_found(tcx.sess, attributes, "borrowck_graphviz_postflow");
 
         let mut mbcx = DataflowBuilder {
-            hir_id,
+            def_id,
             print_preflow_to, print_postflow_to, flow_state: self,
         };
 
diff --git a/src/librustc_mir/transform/elaborate_drops.rs b/src/librustc_mir/transform/elaborate_drops.rs
index d5098bc1db2..023a61588c4 100644
--- a/src/librustc_mir/transform/elaborate_drops.rs
+++ b/src/librustc_mir/transform/elaborate_drops.rs
@@ -28,7 +28,7 @@ impl MirPass for ElaborateDrops {
     {
         debug!("elaborate_drops({:?} @ {:?})", src, mir.span);
 
-        let id = tcx.hir().as_local_hir_id(src.def_id()).unwrap();
+        let def_id = src.def_id();
         let param_env = tcx.param_env(src.def_id()).with_reveal_all();
         let move_data = match MoveData::gather_moves(mir, tcx) {
             Ok(move_data) => move_data,
@@ -50,13 +50,13 @@ impl MirPass for ElaborateDrops {
                 move_data,
                 param_env,
             };
-            let dead_unwinds = find_dead_unwinds(tcx, mir, id, &env);
+            let dead_unwinds = find_dead_unwinds(tcx, mir, def_id, &env);
             let flow_inits =
-                do_dataflow(tcx, mir, id, &[], &dead_unwinds,
+                do_dataflow(tcx, mir, def_id, &[], &dead_unwinds,
                             MaybeInitializedPlaces::new(tcx, mir, &env),
                             |bd, p| DebugFormatted::new(&bd.move_data().move_paths[p]));
             let flow_uninits =
-                do_dataflow(tcx, mir, id, &[], &dead_unwinds,
+                do_dataflow(tcx, mir, def_id, &[], &dead_unwinds,
                             MaybeUninitializedPlaces::new(tcx, mir, &env),
                             |bd, p| DebugFormatted::new(&bd.move_data().move_paths[p]));
 
@@ -80,7 +80,7 @@ impl MirPass for ElaborateDrops {
 fn find_dead_unwinds<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     mir: &Mir<'tcx>,
-    id: hir::HirId,
+    def_id: hir::def_id::DefId,
     env: &MoveDataParamEnv<'tcx, 'tcx>)
     -> BitSet<BasicBlock>
 {
@@ -89,7 +89,7 @@ fn find_dead_unwinds<'a, 'tcx>(
     // reach cleanup blocks, which can't have unwind edges themselves.
     let mut dead_unwinds = BitSet::new_empty(mir.basic_blocks().len());
     let flow_inits =
-        do_dataflow(tcx, mir, id, &[], &dead_unwinds,
+        do_dataflow(tcx, mir, def_id, &[], &dead_unwinds,
                     MaybeInitializedPlaces::new(tcx, mir, &env),
                     |bd, p| DebugFormatted::new(&bd.move_data().move_paths[p]));
     for (bb, bb_data) in mir.basic_blocks().iter_enumerated() {
diff --git a/src/librustc_mir/transform/generator.rs b/src/librustc_mir/transform/generator.rs
index b22258a49b2..c4e303eb9aa 100644
--- a/src/librustc_mir/transform/generator.rs
+++ b/src/librustc_mir/transform/generator.rs
@@ -390,13 +390,13 @@ fn locals_live_across_suspend_points(
     FxHashMap<BasicBlock, liveness::LiveVarSet>,
 ) {
     let dead_unwinds = BitSet::new_empty(mir.basic_blocks().len());
-    let hir_id = tcx.hir().as_local_hir_id(source.def_id()).unwrap();
+    let def_id = source.def_id();
 
     // Calculate when MIR locals have live storage. This gives us an upper bound of their
     // lifetimes.
     let storage_live_analysis = MaybeStorageLive::new(mir);
     let storage_live =
-        do_dataflow(tcx, mir, hir_id, &[], &dead_unwinds, storage_live_analysis,
+        do_dataflow(tcx, mir, def_id, &[], &dead_unwinds, storage_live_analysis,
                     |bd, p| DebugFormatted::new(&bd.mir().local_decls[p]));
 
     // Find the MIR locals which do not use StorageLive/StorageDead statements.
@@ -410,7 +410,7 @@ fn locals_live_across_suspend_points(
     let borrowed_locals = if !movable {
         let analysis = HaveBeenBorrowedLocals::new(mir);
         let result =
-            do_dataflow(tcx, mir, hir_id, &[], &dead_unwinds, analysis,
+            do_dataflow(tcx, mir, def_id, &[], &dead_unwinds, analysis,
                         |bd, p| DebugFormatted::new(&bd.mir().local_decls[p]));
         Some((analysis, result))
     } else {
diff --git a/src/librustc_mir/transform/rustc_peek.rs b/src/librustc_mir/transform/rustc_peek.rs
index f9f8abbe6c0..246f876235d 100644
--- a/src/librustc_mir/transform/rustc_peek.rs
+++ b/src/librustc_mir/transform/rustc_peek.rs
@@ -3,7 +3,7 @@ use syntax::ast;
 use syntax_pos::Span;
 
 use rustc::ty::{self, TyCtxt};
-use rustc::hir;
+use rustc::hir::def_id::DefId;
 use rustc::mir::{self, Mir, Location};
 use rustc_data_structures::bit_set::BitSet;
 use crate::transform::{MirPass, MirSource};
@@ -27,7 +27,6 @@ impl MirPass for SanityCheck {
     fn run_pass<'a, 'tcx>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           src: MirSource<'tcx>, mir: &mut Mir<'tcx>) {
         let def_id = src.def_id();
-        let id = tcx.hir().as_local_hir_id(def_id).unwrap();
         if !tcx.has_attr(def_id, "rustc_mir") {
             debug!("skipping rustc_peek::SanityCheck on {}", tcx.def_path_str(def_id));
             return;
@@ -41,26 +40,26 @@ impl MirPass for SanityCheck {
         let mdpe = MoveDataParamEnv { move_data: move_data, param_env: param_env };
         let dead_unwinds = BitSet::new_empty(mir.basic_blocks().len());
         let flow_inits =
-            do_dataflow(tcx, mir, id, &attributes, &dead_unwinds,
+            do_dataflow(tcx, mir, def_id, &attributes, &dead_unwinds,
                         MaybeInitializedPlaces::new(tcx, mir, &mdpe),
                         |bd, i| DebugFormatted::new(&bd.move_data().move_paths[i]));
         let flow_uninits =
-            do_dataflow(tcx, mir, id, &attributes, &dead_unwinds,
+            do_dataflow(tcx, mir, def_id, &attributes, &dead_unwinds,
                         MaybeUninitializedPlaces::new(tcx, mir, &mdpe),
                         |bd, i| DebugFormatted::new(&bd.move_data().move_paths[i]));
         let flow_def_inits =
-            do_dataflow(tcx, mir, id, &attributes, &dead_unwinds,
+            do_dataflow(tcx, mir, def_id, &attributes, &dead_unwinds,
                         DefinitelyInitializedPlaces::new(tcx, mir, &mdpe),
                         |bd, i| DebugFormatted::new(&bd.move_data().move_paths[i]));
 
         if has_rustc_mir_with(&attributes, "rustc_peek_maybe_init").is_some() {
-            sanity_check_via_rustc_peek(tcx, mir, id, &attributes, &flow_inits);
+            sanity_check_via_rustc_peek(tcx, mir, def_id, &attributes, &flow_inits);
         }
         if has_rustc_mir_with(&attributes, "rustc_peek_maybe_uninit").is_some() {
-            sanity_check_via_rustc_peek(tcx, mir, id, &attributes, &flow_uninits);
+            sanity_check_via_rustc_peek(tcx, mir, def_id, &attributes, &flow_uninits);
         }
         if has_rustc_mir_with(&attributes, "rustc_peek_definite_init").is_some() {
-            sanity_check_via_rustc_peek(tcx, mir, id, &attributes, &flow_def_inits);
+            sanity_check_via_rustc_peek(tcx, mir, def_id, &attributes, &flow_def_inits);
         }
         if has_rustc_mir_with(&attributes, "stop_after_dataflow").is_some() {
             tcx.sess.fatal("stop_after_dataflow ended compilation");
@@ -86,12 +85,12 @@ impl MirPass for SanityCheck {
 /// errors are not intended to be used for unit tests.)
 pub fn sanity_check_via_rustc_peek<'a, 'tcx, O>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                                 mir: &Mir<'tcx>,
-                                                id: hir::HirId,
+                                                def_id: DefId,
                                                 _attributes: &[ast::Attribute],
                                                 results: &DataflowResults<'tcx, O>)
     where O: BitDenotation<'tcx, Idx=MovePathIndex> + HasMoveData<'tcx>
 {
-    debug!("sanity_check_via_rustc_peek id: {:?}", id);
+    debug!("sanity_check_via_rustc_peek def_id: {:?}", def_id);
     // FIXME: this is not DRY. Figure out way to abstract this and
     // `dataflow::build_sets`. (But note it is doing non-standard
     // stuff, so such generalization may not be realistic.)
diff --git a/src/librustc_mir/util/graphviz.rs b/src/librustc_mir/util/graphviz.rs
index 69a2adcfce0..f87714b58c4 100644
--- a/src/librustc_mir/util/graphviz.rs
+++ b/src/librustc_mir/util/graphviz.rs
@@ -1,6 +1,7 @@
 use rustc::hir::def_id::DefId;
 use rustc::mir::*;
 use rustc::ty::TyCtxt;
+use rustc_data_structures::indexed_vec::Idx;
 use std::fmt::Debug;
 use std::io::{self, Write};
 
@@ -20,6 +21,17 @@ pub fn write_mir_graphviz<'tcx, W>(tcx: TyCtxt<'_, '_, 'tcx>,
     Ok(())
 }
 
+// Must match `[0-9A-Za-z_]*`. This does not appear in the rendered graph, so
+// it does not have to be user friendly.
+pub fn graphviz_safe_def_name(def_id: DefId) -> String {
+    format!(
+        "{}_{}_{}",
+        def_id.krate.index(),
+        def_id.index.address_space().index(),
+        def_id.index.as_array_index(),
+    )
+}
+
 /// Write a graphviz DOT graph of the MIR.
 pub fn write_mir_fn_graphviz<'tcx, W>(tcx: TyCtxt<'_, '_, 'tcx>,
                                       def_id: DefId,
@@ -27,7 +39,7 @@ pub fn write_mir_fn_graphviz<'tcx, W>(tcx: TyCtxt<'_, '_, 'tcx>,
                                       w: &mut W) -> io::Result<()>
     where W: Write
 {
-    writeln!(w, "digraph Mir_{} {{", tcx.hir().as_local_hir_id(def_id).unwrap())?;
+    writeln!(w, "digraph Mir_{} {{", graphviz_safe_def_name(def_id))?;
 
     // Global graph properties
     writeln!(w, r#"    graph [fontname="monospace"];"#)?;
diff --git a/src/librustc_mir/util/mod.rs b/src/librustc_mir/util/mod.rs
index 29614a33f8e..1a5a2a92247 100644
--- a/src/librustc_mir/util/mod.rs
+++ b/src/librustc_mir/util/mod.rs
@@ -15,7 +15,7 @@ pub mod collect_writes;
 
 pub use self::alignment::is_disaligned;
 pub use self::pretty::{dump_enabled, dump_mir, write_mir_pretty, PassWhere};
-pub use self::graphviz::{write_mir_graphviz};
+pub use self::graphviz::{graphviz_safe_def_name, write_mir_graphviz};
 pub use self::graphviz::write_node_label as write_graphviz_node_label;
 
 /// If possible, suggest replacing `ref` with `ref mut`.
diff --git a/src/test/mir-opt/graphviz.rs b/src/test/mir-opt/graphviz.rs
new file mode 100644
index 00000000000..660576996e5
--- /dev/null
+++ b/src/test/mir-opt/graphviz.rs
@@ -0,0 +1,23 @@
+// Test graphviz output
+// compile-flags: -Z dump-mir-graphviz
+
+// ignore-tidy-linelength
+
+fn main() {}
+
+// END RUST SOURCE
+// START rustc.main.mir_map.0.dot
+// digraph Mir_0_0_3 { // The name here MUST be an ASCII identifier.
+//     graph [fontname="monospace"];
+//     node [fontname="monospace"];
+//     edge [fontname="monospace"];
+//     label=<fn main() -&gt; ()<br align="left"/>>;
+//     bb0 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">0</td></tr><tr><td align="left" balign="left">_0 = ()<br/></td></tr><tr><td align="left">goto</td></tr></table>
+// >];
+//     bb1 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">1</td></tr><tr><td align="left">resume</td></tr></table>
+// >];
+//     bb2 [shape="none", label=<<table border="0" cellborder="1" cellspacing="0"><tr><td bgcolor="gray" align="center" colspan="1">2</td></tr><tr><td align="left">return</td></tr></table>
+// >];
+//     bb0 -> bb2 [label=""];
+// }
+// END rustc.main.mir_map.0.dot