diff options
| -rw-r--r-- | compiler/rustc_borrowck/src/polonius/dump.rs | 110 |
1 files changed, 101 insertions, 9 deletions
diff --git a/compiler/rustc_borrowck/src/polonius/dump.rs b/compiler/rustc_borrowck/src/polonius/dump.rs index f71e6f3e6f3..6d32ee17f4c 100644 --- a/compiler/rustc_borrowck/src/polonius/dump.rs +++ b/compiler/rustc_borrowck/src/polonius/dump.rs @@ -1,17 +1,19 @@ use std::io; -use rustc_data_structures::fx::FxHashSet; +use rustc_data_structures::fx::{FxHashSet, FxIndexMap, FxIndexSet}; use rustc_index::IndexVec; use rustc_middle::mir::pretty::{ PassWhere, PrettyPrintMirOptions, create_dump_file, dump_enabled, dump_mir_to_writer, }; -use rustc_middle::mir::{Body, ClosureRegionRequirements}; +use rustc_middle::mir::{Body, ClosureRegionRequirements, Location}; use rustc_middle::ty::{RegionVid, TyCtxt}; +use rustc_mir_dataflow::points::PointIndex; use rustc_session::config::MirIncludeSpans; use crate::borrow_set::BorrowSet; use crate::constraints::OutlivesConstraint; use crate::polonius::{LocalizedOutlivesConstraint, LocalizedOutlivesConstraintSet}; +use crate::region_infer::values::LivenessValues; use crate::type_check::Locations; use crate::{BorrowckInferCtxt, RegionInferenceContext}; @@ -80,14 +82,27 @@ fn emit_polonius_dump<'tcx>( body, regioncx, borrow_set, - localized_outlives_constraints, + &localized_outlives_constraints, closure_region_requirements, out, )?; writeln!(out, "</code></pre>")?; writeln!(out, "</div>")?; - // Section 2: mermaid visualization of the CFG. + // Section 2: mermaid visualization of the polonius constraint graph. + writeln!(out, "<div>")?; + writeln!(out, "Polonius constraint graph")?; + writeln!(out, "<pre class='mermaid'>")?; + let edge_count = emit_mermaid_constraint_graph( + borrow_set, + regioncx.liveness_constraints(), + &localized_outlives_constraints, + out, + )?; + writeln!(out, "</pre>")?; + writeln!(out, "</div>")?; + + // Section 3: mermaid visualization of the CFG. writeln!(out, "<div>")?; writeln!(out, "Control-flow graph")?; writeln!(out, "<pre class='mermaid'>")?; @@ -95,7 +110,7 @@ fn emit_polonius_dump<'tcx>( writeln!(out, "</pre>")?; writeln!(out, "</div>")?; - // Section 3: mermaid visualization of the NLL region graph. + // Section 4: mermaid visualization of the NLL region graph. writeln!(out, "<div>")?; writeln!(out, "NLL regions")?; writeln!(out, "<pre class='mermaid'>")?; @@ -103,7 +118,7 @@ fn emit_polonius_dump<'tcx>( writeln!(out, "</pre>")?; writeln!(out, "</div>")?; - // Section 4: mermaid visualization of the NLL SCC graph. + // Section 5: mermaid visualization of the NLL SCC graph. writeln!(out, "<div>")?; writeln!(out, "NLL SCCs")?; writeln!(out, "<pre class='mermaid'>")?; @@ -117,7 +132,11 @@ fn emit_polonius_dump<'tcx>( "<script src='https://cdn.jsdelivr.net/npm/mermaid/dist/mermaid.min.js'></script>" )?; writeln!(out, "<script>")?; - writeln!(out, "mermaid.initialize({{ startOnLoad: false, maxEdges: 100 }});")?; + writeln!( + out, + "mermaid.initialize({{ startOnLoad: false, maxEdges: {} }});", + edge_count.max(100), + )?; writeln!(out, "mermaid.run({{ querySelector: '.mermaid' }})")?; writeln!(out, "</script>")?; writeln!(out, "</body>")?; @@ -132,7 +151,7 @@ fn emit_html_mir<'tcx>( body: &Body<'tcx>, regioncx: &RegionInferenceContext<'tcx>, borrow_set: &BorrowSet<'tcx>, - localized_outlives_constraints: LocalizedOutlivesConstraintSet, + localized_outlives_constraints: &LocalizedOutlivesConstraintSet, closure_region_requirements: &Option<ClosureRegionRequirements<'tcx>>, out: &mut dyn io::Write, ) -> io::Result<()> { @@ -160,7 +179,7 @@ fn emit_html_mir<'tcx>( regioncx, closure_region_requirements, borrow_set, - &localized_outlives_constraints, + localized_outlives_constraints, pass_where, out, ) @@ -392,3 +411,76 @@ fn emit_mermaid_nll_sccs<'tcx>( Ok(()) } + +/// Emits a mermaid flowchart of the polonius localized outlives constraints, with subgraphs per +/// region, and loan introductions. +fn emit_mermaid_constraint_graph<'tcx>( + borrow_set: &BorrowSet<'tcx>, + liveness: &LivenessValues, + localized_outlives_constraints: &LocalizedOutlivesConstraintSet, + out: &mut dyn io::Write, +) -> io::Result<usize> { + let location_name = |location: Location| { + // A MIR location looks like `bb5[2]`. As that is not a syntactically valid mermaid node id, + // transform it into `BB5_2`. + format!("BB{}_{}", location.block.index(), location.statement_index) + }; + let region_name = |region: RegionVid| format!("'{}", region.index()); + let node_name = |region: RegionVid, point: PointIndex| { + let location = liveness.location_from_point(point); + format!("{}_{}", region_name(region), location_name(location)) + }; + + // The mermaid chart type: a top-down flowchart, which supports subgraphs. + writeln!(out, "flowchart TD")?; + + // The loans subgraph: a node per loan. + writeln!(out, " subgraph \"Loans\"")?; + for loan_idx in 0..borrow_set.len() { + writeln!(out, " L{loan_idx}")?; + } + writeln!(out, " end\n")?; + + // And an edge from that loan node to where it enters the constraint graph. + for (loan_idx, loan) in borrow_set.iter_enumerated() { + writeln!( + out, + " L{} --> {}_{}", + loan_idx.index(), + region_name(loan.region), + location_name(loan.reserve_location), + )?; + } + writeln!(out, "")?; + + // The regions subgraphs containing the region/point nodes. + let mut points_per_region: FxIndexMap<RegionVid, FxIndexSet<PointIndex>> = + FxIndexMap::default(); + for constraint in &localized_outlives_constraints.outlives { + points_per_region.entry(constraint.source).or_default().insert(constraint.from); + points_per_region.entry(constraint.target).or_default().insert(constraint.to); + } + for (region, points) in points_per_region { + writeln!(out, " subgraph \"{}\"", region_name(region))?; + for point in points { + writeln!(out, " {}", node_name(region, point))?; + } + writeln!(out, " end\n")?; + } + + // The constraint graph edges. + for constraint in &localized_outlives_constraints.outlives { + // FIXME: add killed loans and constraint kind as edge labels. + writeln!( + out, + " {} --> {}", + node_name(constraint.source, constraint.from), + node_name(constraint.target, constraint.to), + )?; + } + + // Return the number of edges: this is the biggest graph in the dump and its edge count will be + // mermaid's max edge count to support. + let edge_count = borrow_set.len() + localized_outlives_constraints.outlives.len(); + Ok(edge_count) +} |