diff options
| -rw-r--r-- | compiler/rustc_mir_transform/src/coverage/graph.rs | 116 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/coverage/tests.rs | 2 |
2 files changed, 38 insertions, 80 deletions
diff --git a/compiler/rustc_mir_transform/src/coverage/graph.rs b/compiler/rustc_mir_transform/src/coverage/graph.rs index 812633348e3..39027d21f06 100644 --- a/compiler/rustc_mir_transform/src/coverage/graph.rs +++ b/compiler/rustc_mir_transform/src/coverage/graph.rs @@ -1,8 +1,9 @@ +use rustc_data_structures::captures::Captures; use rustc_data_structures::graph::dominators::{self, Dominators}; use rustc_data_structures::graph::{self, GraphSuccessors, WithNumNodes, WithStartNode}; use rustc_index::bit_set::BitSet; use rustc_index::{IndexSlice, IndexVec}; -use rustc_middle::mir::{self, BasicBlock, BasicBlockData, Terminator, TerminatorKind}; +use rustc_middle::mir::{self, BasicBlock, TerminatorKind}; use std::cmp::Ordering; use std::ops::{Index, IndexMut}; @@ -36,9 +37,8 @@ impl CoverageGraph { } let bcb_data = &bcbs[bcb]; let mut bcb_successors = Vec::new(); - for successor in - bcb_filtered_successors(&mir_body, &bcb_data.terminator(mir_body).kind) - .filter_map(|successor_bb| bb_to_bcb[successor_bb]) + for successor in bcb_filtered_successors(&mir_body, bcb_data.last_bb()) + .filter_map(|successor_bb| bb_to_bcb[successor_bb]) { if !seen[successor] { seen[successor] = true; @@ -80,10 +80,9 @@ impl CoverageGraph { // intentionally omits unwind paths. // FIXME(#78544): MIR InstrumentCoverage: Improve coverage of `#[should_panic]` tests and // `catch_unwind()` handlers. - let mir_cfg_without_unwind = ShortCircuitPreorder::new(&mir_body, bcb_filtered_successors); let mut basic_blocks = Vec::new(); - for (bb, data) in mir_cfg_without_unwind { + for bb in short_circuit_preorder(mir_body, bcb_filtered_successors) { if let Some(last) = basic_blocks.last() { let predecessors = &mir_body.basic_blocks.predecessors()[bb]; if predecessors.len() > 1 || !predecessors.contains(last) { @@ -109,7 +108,7 @@ impl CoverageGraph { } basic_blocks.push(bb); - let term = data.terminator(); + let term = mir_body[bb].terminator(); match term.kind { TerminatorKind::Return { .. } @@ -316,11 +315,6 @@ impl BasicCoverageBlockData { pub fn last_bb(&self) -> BasicBlock { *self.basic_blocks.last().unwrap() } - - #[inline(always)] - pub fn terminator<'a, 'tcx>(&self, mir_body: &'a mir::Body<'tcx>) -> &'a Terminator<'tcx> { - &mir_body[self.last_bb()].terminator() - } } /// Represents a successor from a branching BasicCoverageBlock (such as the arms of a `SwitchInt`) @@ -362,26 +356,28 @@ impl std::fmt::Debug for BcbBranch { } } -// Returns the `Terminator`s non-unwind successors. +// Returns the subset of a block's successors that are relevant to the coverage +// graph, i.e. those that do not represent unwinds or unreachable branches. // FIXME(#78544): MIR InstrumentCoverage: Improve coverage of `#[should_panic]` tests and // `catch_unwind()` handlers. fn bcb_filtered_successors<'a, 'tcx>( body: &'a mir::Body<'tcx>, - term_kind: &'a TerminatorKind<'tcx>, -) -> Box<dyn Iterator<Item = BasicBlock> + 'a> { - Box::new( - match &term_kind { - // SwitchInt successors are never unwind, and all of them should be traversed. - TerminatorKind::SwitchInt { ref targets, .. } => { - None.into_iter().chain(targets.all_targets().into_iter().copied()) - } - // For all other kinds, return only the first successor, if any, and ignore unwinds. - // NOTE: `chain(&[])` is required to coerce the `option::iter` (from - // `next().into_iter()`) into the `mir::Successors` aliased type. - _ => term_kind.successors().next().into_iter().chain((&[]).into_iter().copied()), - } - .filter(move |&successor| body[successor].terminator().kind != TerminatorKind::Unreachable), - ) + bb: BasicBlock, +) -> impl Iterator<Item = BasicBlock> + Captures<'a> + Captures<'tcx> { + let terminator = body[bb].terminator(); + + let take_n_successors = match terminator.kind { + // SwitchInt successors are never unwinds, so all of them should be traversed. + TerminatorKind::SwitchInt { .. } => usize::MAX, + // For all other kinds, return only the first successor (if any), ignoring any + // unwind successors. + _ => 1, + }; + + terminator + .successors() + .take(take_n_successors) + .filter(move |&successor| body[successor].terminator().kind != TerminatorKind::Unreachable) } /// Maintains separate worklists for each loop in the BasicCoverageBlock CFG, plus one for the @@ -553,66 +549,28 @@ pub(super) fn find_loop_backedges( backedges } -pub struct ShortCircuitPreorder< - 'a, - 'tcx, - F: Fn(&'a mir::Body<'tcx>, &'a TerminatorKind<'tcx>) -> Box<dyn Iterator<Item = BasicBlock> + 'a>, -> { +fn short_circuit_preorder<'a, 'tcx, F, Iter>( body: &'a mir::Body<'tcx>, - visited: BitSet<BasicBlock>, - worklist: Vec<BasicBlock>, filtered_successors: F, -} - -impl< - 'a, - 'tcx, - F: Fn(&'a mir::Body<'tcx>, &'a TerminatorKind<'tcx>) -> Box<dyn Iterator<Item = BasicBlock> + 'a>, -> ShortCircuitPreorder<'a, 'tcx, F> +) -> impl Iterator<Item = BasicBlock> + Captures<'a> + Captures<'tcx> +where + F: Fn(&'a mir::Body<'tcx>, BasicBlock) -> Iter, + Iter: Iterator<Item = BasicBlock>, { - pub fn new( - body: &'a mir::Body<'tcx>, - filtered_successors: F, - ) -> ShortCircuitPreorder<'a, 'tcx, F> { - let worklist = vec![mir::START_BLOCK]; - - ShortCircuitPreorder { - body, - visited: BitSet::new_empty(body.basic_blocks.len()), - worklist, - filtered_successors, - } - } -} - -impl< - 'a, - 'tcx, - F: Fn(&'a mir::Body<'tcx>, &'a TerminatorKind<'tcx>) -> Box<dyn Iterator<Item = BasicBlock> + 'a>, -> Iterator for ShortCircuitPreorder<'a, 'tcx, F> -{ - type Item = (BasicBlock, &'a BasicBlockData<'tcx>); + let mut visited = BitSet::new_empty(body.basic_blocks.len()); + let mut worklist = vec![mir::START_BLOCK]; - fn next(&mut self) -> Option<(BasicBlock, &'a BasicBlockData<'tcx>)> { - while let Some(idx) = self.worklist.pop() { - if !self.visited.insert(idx) { + std::iter::from_fn(move || { + while let Some(bb) = worklist.pop() { + if !visited.insert(bb) { continue; } - let data = &self.body[idx]; - - if let Some(ref term) = data.terminator { - self.worklist.extend((self.filtered_successors)(&self.body, &term.kind)); - } + worklist.extend(filtered_successors(body, bb)); - return Some((idx, data)); + return Some(bb); } None - } - - fn size_hint(&self) -> (usize, Option<usize>) { - let size = self.body.basic_blocks.len() - self.visited.count(); - (size, Some(size)) - } + }) } diff --git a/compiler/rustc_mir_transform/src/coverage/tests.rs b/compiler/rustc_mir_transform/src/coverage/tests.rs index 7476d3ce927..ee7cb791c81 100644 --- a/compiler/rustc_mir_transform/src/coverage/tests.rs +++ b/compiler/rustc_mir_transform/src/coverage/tests.rs @@ -241,7 +241,7 @@ fn print_coverage_graphviz( " {:?} [label=\"{:?}: {}\"];\n{}", bcb, bcb, - bcb_data.terminator(mir_body).kind.name(), + mir_body[bcb_data.last_bb()].terminator().kind.name(), basic_coverage_blocks .successors(bcb) .map(|successor| { format!(" {:?} -> {:?};", bcb, successor) }) |