mirror of
https://github.com/rust-lang/rust.git
synced 2025-04-30 12:07:40 +00:00
95c268f64d
Fixes: #79725 Some macros can create a situation where `fn_sig_span` and `body_span` map to different files. New documentation on coverage tests incorrectly assumed multiple test binaries could just be listed at the end of the `llvm-cov` command, but it turns out each binary needs a `--object` prefix. This PR fixes the bug and updates the documentation to correct that issue. It also fixes a few other minor issues in internal implementation comments, and adds documentation on getting coverage results for doc tests.
738 lines
33 KiB
Rust
738 lines
33 KiB
Rust
use super::debug::term_type;
|
|
use super::graph::{BasicCoverageBlock, BasicCoverageBlockData, CoverageGraph, START_BCB};
|
|
|
|
use crate::util::spanview::source_range_no_file;
|
|
|
|
use rustc_data_structures::graph::WithNumNodes;
|
|
use rustc_middle::mir::{
|
|
self, AggregateKind, BasicBlock, FakeReadCause, Rvalue, Statement, StatementKind, Terminator,
|
|
TerminatorKind,
|
|
};
|
|
use rustc_middle::ty::TyCtxt;
|
|
|
|
use rustc_span::source_map::original_sp;
|
|
use rustc_span::{BytePos, Span, SyntaxContext};
|
|
|
|
use std::cmp::Ordering;
|
|
|
|
#[derive(Debug, Copy, Clone)]
|
|
pub(super) enum CoverageStatement {
|
|
Statement(BasicBlock, Span, usize),
|
|
Terminator(BasicBlock, Span),
|
|
}
|
|
|
|
impl CoverageStatement {
|
|
pub fn format(&self, tcx: TyCtxt<'tcx>, mir_body: &'a mir::Body<'tcx>) -> String {
|
|
match *self {
|
|
Self::Statement(bb, span, stmt_index) => {
|
|
let stmt = &mir_body[bb].statements[stmt_index];
|
|
format!(
|
|
"{}: @{}[{}]: {:?}",
|
|
source_range_no_file(tcx, &span),
|
|
bb.index(),
|
|
stmt_index,
|
|
stmt
|
|
)
|
|
}
|
|
Self::Terminator(bb, span) => {
|
|
let term = mir_body[bb].terminator();
|
|
format!(
|
|
"{}: @{}.{}: {:?}",
|
|
source_range_no_file(tcx, &span),
|
|
bb.index(),
|
|
term_type(&term.kind),
|
|
term.kind
|
|
)
|
|
}
|
|
}
|
|
}
|
|
|
|
pub fn span(&self) -> &Span {
|
|
match self {
|
|
Self::Statement(_, span, _) | Self::Terminator(_, span) => span,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// A BCB is deconstructed into one or more `Span`s. Each `Span` maps to a `CoverageSpan` that
|
|
/// references the originating BCB and one or more MIR `Statement`s and/or `Terminator`s.
|
|
/// Initially, the `Span`s come from the `Statement`s and `Terminator`s, but subsequent
|
|
/// transforms can combine adjacent `Span`s and `CoverageSpan` from the same BCB, merging the
|
|
/// `CoverageStatement` vectors, and the `Span`s to cover the extent of the combined `Span`s.
|
|
///
|
|
/// Note: A `CoverageStatement` merged into another CoverageSpan may come from a `BasicBlock` that
|
|
/// is not part of the `CoverageSpan` bcb if the statement was included because it's `Span` matches
|
|
/// or is subsumed by the `Span` associated with this `CoverageSpan`, and it's `BasicBlock`
|
|
/// `is_dominated_by()` the `BasicBlock`s in this `CoverageSpan`.
|
|
#[derive(Debug, Clone)]
|
|
pub(super) struct CoverageSpan {
|
|
pub span: Span,
|
|
pub bcb: BasicCoverageBlock,
|
|
pub coverage_statements: Vec<CoverageStatement>,
|
|
pub is_closure: bool,
|
|
}
|
|
|
|
impl CoverageSpan {
|
|
pub fn for_fn_sig(fn_sig_span: Span) -> Self {
|
|
Self { span: fn_sig_span, bcb: START_BCB, coverage_statements: vec![], is_closure: false }
|
|
}
|
|
|
|
pub fn for_statement(
|
|
statement: &Statement<'tcx>,
|
|
span: Span,
|
|
bcb: BasicCoverageBlock,
|
|
bb: BasicBlock,
|
|
stmt_index: usize,
|
|
) -> Self {
|
|
let is_closure = match statement.kind {
|
|
StatementKind::Assign(box (_, Rvalue::Aggregate(box ref kind, _))) => match kind {
|
|
AggregateKind::Closure(_, _) | AggregateKind::Generator(_, _, _) => true,
|
|
_ => false,
|
|
},
|
|
_ => false,
|
|
};
|
|
|
|
Self {
|
|
span,
|
|
bcb,
|
|
coverage_statements: vec![CoverageStatement::Statement(bb, span, stmt_index)],
|
|
is_closure,
|
|
}
|
|
}
|
|
|
|
pub fn for_terminator(span: Span, bcb: BasicCoverageBlock, bb: BasicBlock) -> Self {
|
|
Self {
|
|
span,
|
|
bcb,
|
|
coverage_statements: vec![CoverageStatement::Terminator(bb, span)],
|
|
is_closure: false,
|
|
}
|
|
}
|
|
|
|
pub fn merge_from(&mut self, mut other: CoverageSpan) {
|
|
debug_assert!(self.is_mergeable(&other));
|
|
self.span = self.span.to(other.span);
|
|
self.coverage_statements.append(&mut other.coverage_statements);
|
|
}
|
|
|
|
pub fn cutoff_statements_at(&mut self, cutoff_pos: BytePos) {
|
|
self.coverage_statements.retain(|covstmt| covstmt.span().hi() <= cutoff_pos);
|
|
if let Some(highest_covstmt) =
|
|
self.coverage_statements.iter().max_by_key(|covstmt| covstmt.span().hi())
|
|
{
|
|
self.span = self.span.with_hi(highest_covstmt.span().hi());
|
|
}
|
|
}
|
|
|
|
#[inline]
|
|
pub fn is_mergeable(&self, other: &Self) -> bool {
|
|
self.is_in_same_bcb(other) && !(self.is_closure || other.is_closure)
|
|
}
|
|
|
|
#[inline]
|
|
pub fn is_in_same_bcb(&self, other: &Self) -> bool {
|
|
self.bcb == other.bcb
|
|
}
|
|
|
|
pub fn format(&self, tcx: TyCtxt<'tcx>, mir_body: &'a mir::Body<'tcx>) -> String {
|
|
format!(
|
|
"{}\n {}",
|
|
source_range_no_file(tcx, &self.span),
|
|
self.format_coverage_statements(tcx, mir_body).replace("\n", "\n "),
|
|
)
|
|
}
|
|
|
|
pub fn format_coverage_statements(
|
|
&self,
|
|
tcx: TyCtxt<'tcx>,
|
|
mir_body: &'a mir::Body<'tcx>,
|
|
) -> String {
|
|
let mut sorted_coverage_statements = self.coverage_statements.clone();
|
|
sorted_coverage_statements.sort_unstable_by_key(|covstmt| match *covstmt {
|
|
CoverageStatement::Statement(bb, _, index) => (bb, index),
|
|
CoverageStatement::Terminator(bb, _) => (bb, usize::MAX),
|
|
});
|
|
sorted_coverage_statements
|
|
.iter()
|
|
.map(|covstmt| covstmt.format(tcx, mir_body))
|
|
.collect::<Vec<_>>()
|
|
.join("\n")
|
|
}
|
|
}
|
|
|
|
/// Converts the initial set of `CoverageSpan`s (one per MIR `Statement` or `Terminator`) into a
|
|
/// minimal set of `CoverageSpan`s, using the BCB CFG to determine where it is safe and useful to:
|
|
///
|
|
/// * Remove duplicate source code coverage regions
|
|
/// * Merge spans that represent continuous (both in source code and control flow), non-branching
|
|
/// execution
|
|
/// * Carve out (leave uncovered) any span that will be counted by another MIR (notably, closures)
|
|
pub struct CoverageSpans<'a, 'tcx> {
|
|
/// The MIR, used to look up `BasicBlockData`.
|
|
mir_body: &'a mir::Body<'tcx>,
|
|
|
|
/// A `Span` covering the signature of function for the MIR.
|
|
fn_sig_span: Span,
|
|
|
|
/// A `Span` covering the function body of the MIR (typically from left curly brace to right
|
|
/// curly brace).
|
|
body_span: Span,
|
|
|
|
/// The BasicCoverageBlock Control Flow Graph (BCB CFG).
|
|
basic_coverage_blocks: &'a CoverageGraph,
|
|
|
|
/// The initial set of `CoverageSpan`s, sorted by `Span` (`lo` and `hi`) and by relative
|
|
/// dominance between the `BasicCoverageBlock`s of equal `Span`s.
|
|
sorted_spans_iter: Option<std::vec::IntoIter<CoverageSpan>>,
|
|
|
|
/// The current `CoverageSpan` to compare to its `prev`, to possibly merge, discard, force the
|
|
/// discard of the `prev` (and or `pending_dups`), or keep both (with `prev` moved to
|
|
/// `pending_dups`). If `curr` is not discarded or merged, it becomes `prev` for the next
|
|
/// iteration.
|
|
some_curr: Option<CoverageSpan>,
|
|
|
|
/// The original `span` for `curr`, in case the `curr` span is modified.
|
|
curr_original_span: Span,
|
|
|
|
/// The CoverageSpan from a prior iteration; typically assigned from that iteration's `curr`.
|
|
/// If that `curr` was discarded, `prev` retains its value from the previous iteration.
|
|
some_prev: Option<CoverageSpan>,
|
|
|
|
/// Assigned from `curr_original_span` from the previous iteration.
|
|
prev_original_span: Span,
|
|
|
|
/// One or more `CoverageSpan`s with the same `Span` but different `BasicCoverageBlock`s, and
|
|
/// no `BasicCoverageBlock` in this list dominates another `BasicCoverageBlock` in the list.
|
|
/// If a new `curr` span also fits this criteria (compared to an existing list of
|
|
/// `pending_dups`), that `curr` `CoverageSpan` moves to `prev` before possibly being added to
|
|
/// the `pending_dups` list, on the next iteration. As a result, if `prev` and `pending_dups`
|
|
/// have the same `Span`, the criteria for `pending_dups` holds for `prev` as well: a `prev`
|
|
/// with a matching `Span` does not dominate any `pending_dup` and no `pending_dup` dominates a
|
|
/// `prev` with a matching `Span`)
|
|
pending_dups: Vec<CoverageSpan>,
|
|
|
|
/// The final `CoverageSpan`s to add to the coverage map. A `Counter` or `Expression`
|
|
/// will also be injected into the MIR for each `CoverageSpan`.
|
|
refined_spans: Vec<CoverageSpan>,
|
|
}
|
|
|
|
impl<'a, 'tcx> CoverageSpans<'a, 'tcx> {
|
|
/// Generate a minimal set of `CoverageSpan`s, each representing a contiguous code region to be
|
|
/// counted.
|
|
///
|
|
/// The basic steps are:
|
|
///
|
|
/// 1. Extract an initial set of spans from the `Statement`s and `Terminator`s of each
|
|
/// `BasicCoverageBlockData`.
|
|
/// 2. Sort the spans by span.lo() (starting position). Spans that start at the same position
|
|
/// are sorted with longer spans before shorter spans; and equal spans are sorted
|
|
/// (deterministically) based on "dominator" relationship (if any).
|
|
/// 3. Traverse the spans in sorted order to identify spans that can be dropped (for instance,
|
|
/// if another span or spans are already counting the same code region), or should be merged
|
|
/// into a broader combined span (because it represents a contiguous, non-branching, and
|
|
/// uninterrupted region of source code).
|
|
///
|
|
/// Closures are exposed in their enclosing functions as `Assign` `Rvalue`s, and since
|
|
/// closures have their own MIR, their `Span` in their enclosing function should be left
|
|
/// "uncovered".
|
|
///
|
|
/// Note the resulting vector of `CoverageSpan`s may not be fully sorted (and does not need
|
|
/// to be).
|
|
pub(super) fn generate_coverage_spans(
|
|
mir_body: &'a mir::Body<'tcx>,
|
|
fn_sig_span: Span,
|
|
body_span: Span,
|
|
basic_coverage_blocks: &'a CoverageGraph,
|
|
) -> Vec<CoverageSpan> {
|
|
let mut coverage_spans = CoverageSpans {
|
|
mir_body,
|
|
fn_sig_span,
|
|
body_span,
|
|
basic_coverage_blocks,
|
|
sorted_spans_iter: None,
|
|
refined_spans: Vec::with_capacity(basic_coverage_blocks.num_nodes() * 2),
|
|
some_curr: None,
|
|
curr_original_span: Span::with_root_ctxt(BytePos(0), BytePos(0)),
|
|
some_prev: None,
|
|
prev_original_span: Span::with_root_ctxt(BytePos(0), BytePos(0)),
|
|
pending_dups: Vec::new(),
|
|
};
|
|
|
|
let sorted_spans = coverage_spans.mir_to_initial_sorted_coverage_spans();
|
|
|
|
coverage_spans.sorted_spans_iter = Some(sorted_spans.into_iter());
|
|
coverage_spans.some_prev = coverage_spans.sorted_spans_iter.as_mut().unwrap().next();
|
|
coverage_spans.prev_original_span =
|
|
coverage_spans.some_prev.as_ref().expect("at least one span").span;
|
|
|
|
coverage_spans.to_refined_spans()
|
|
}
|
|
|
|
fn mir_to_initial_sorted_coverage_spans(&self) -> Vec<CoverageSpan> {
|
|
let mut initial_spans = Vec::<CoverageSpan>::with_capacity(self.mir_body.num_nodes() * 2);
|
|
for (bcb, bcb_data) in self.basic_coverage_blocks.iter_enumerated() {
|
|
for coverage_span in self.bcb_to_initial_coverage_spans(bcb, bcb_data) {
|
|
initial_spans.push(coverage_span);
|
|
}
|
|
}
|
|
|
|
if initial_spans.is_empty() {
|
|
// This can happen if, for example, the function is unreachable (contains only a
|
|
// `BasicBlock`(s) with an `Unreachable` terminator).
|
|
return initial_spans;
|
|
}
|
|
|
|
initial_spans.push(CoverageSpan::for_fn_sig(self.fn_sig_span));
|
|
|
|
initial_spans.sort_unstable_by(|a, b| {
|
|
if a.span.lo() == b.span.lo() {
|
|
if a.span.hi() == b.span.hi() {
|
|
if a.is_in_same_bcb(b) {
|
|
Some(Ordering::Equal)
|
|
} else {
|
|
// Sort equal spans by dominator relationship, in reverse order (so
|
|
// dominators always come after the dominated equal spans). When later
|
|
// comparing two spans in order, the first will either dominate the second,
|
|
// or they will have no dominator relationship.
|
|
self.basic_coverage_blocks.dominators().rank_partial_cmp(b.bcb, a.bcb)
|
|
}
|
|
} else {
|
|
// Sort hi() in reverse order so shorter spans are attempted after longer spans.
|
|
// This guarantees that, if a `prev` span overlaps, and is not equal to, a
|
|
// `curr` span, the prev span either extends further left of the curr span, or
|
|
// they start at the same position and the prev span extends further right of
|
|
// the end of the curr span.
|
|
b.span.hi().partial_cmp(&a.span.hi())
|
|
}
|
|
} else {
|
|
a.span.lo().partial_cmp(&b.span.lo())
|
|
}
|
|
.unwrap()
|
|
});
|
|
|
|
initial_spans
|
|
}
|
|
|
|
/// Iterate through the sorted `CoverageSpan`s, and return the refined list of merged and
|
|
/// de-duplicated `CoverageSpan`s.
|
|
fn to_refined_spans(mut self) -> Vec<CoverageSpan> {
|
|
while self.next_coverage_span() {
|
|
if self.curr().is_mergeable(self.prev()) {
|
|
debug!(" same bcb (and neither is a closure), merge with prev={:?}", self.prev());
|
|
let prev = self.take_prev();
|
|
self.curr_mut().merge_from(prev);
|
|
// Note that curr.span may now differ from curr_original_span
|
|
} else if self.prev_ends_before_curr() {
|
|
debug!(
|
|
" different bcbs and disjoint spans, so keep curr for next iter, and add \
|
|
prev={:?}",
|
|
self.prev()
|
|
);
|
|
let prev = self.take_prev();
|
|
self.refined_spans.push(prev);
|
|
} else if self.prev().is_closure {
|
|
// drop any equal or overlapping span (`curr`) and keep `prev` to test again in the
|
|
// next iter
|
|
debug!(
|
|
" curr overlaps a closure (prev). Drop curr and keep prev for next iter. \
|
|
prev={:?}",
|
|
self.prev()
|
|
);
|
|
self.take_curr();
|
|
} else if self.curr().is_closure {
|
|
self.carve_out_span_for_closure();
|
|
} else if self.prev_original_span == self.curr().span {
|
|
// Note that this compares the new span to `prev_original_span`, which may not
|
|
// be the full `prev.span` (if merged during the previous iteration).
|
|
self.hold_pending_dups_unless_dominated();
|
|
} else {
|
|
self.cutoff_prev_at_overlapping_curr();
|
|
}
|
|
}
|
|
|
|
debug!(" AT END, adding last prev={:?}", self.prev());
|
|
let prev = self.take_prev();
|
|
let CoverageSpans { pending_dups, mut refined_spans, .. } = self;
|
|
for dup in pending_dups {
|
|
debug!(" ...adding at least one pending dup={:?}", dup);
|
|
refined_spans.push(dup);
|
|
}
|
|
|
|
// Async functions wrap a closure that implements the body to be executed. The enclosing
|
|
// function is called and returns an `impl Future` without initially executing any of the
|
|
// body. To avoid showing the return from the enclosing function as a "covered" return from
|
|
// the closure, the enclosing function's `TerminatorKind::Return`s `CoverageSpan` is
|
|
// excluded. The closure's `Return` is the only one that will be counted. This provides
|
|
// adequate coverage, and more intuitive counts. (Avoids double-counting the closing brace
|
|
// of the function body.)
|
|
let body_ends_with_closure = if let Some(last_covspan) = refined_spans.last() {
|
|
last_covspan.is_closure && last_covspan.span.hi() == self.body_span.hi()
|
|
} else {
|
|
false
|
|
};
|
|
|
|
if !body_ends_with_closure {
|
|
refined_spans.push(prev);
|
|
}
|
|
|
|
// Remove `CoverageSpan`s derived from closures, originally added to ensure the coverage
|
|
// regions for the current function leave room for the closure's own coverage regions
|
|
// (injected separately, from the closure's own MIR).
|
|
refined_spans.retain(|covspan| !covspan.is_closure);
|
|
refined_spans
|
|
}
|
|
|
|
// Generate a set of `CoverageSpan`s from the filtered set of `Statement`s and `Terminator`s of
|
|
// the `BasicBlock`(s) in the given `BasicCoverageBlockData`. One `CoverageSpan` is generated
|
|
// for each `Statement` and `Terminator`. (Note that subsequent stages of coverage analysis will
|
|
// merge some `CoverageSpan`s, at which point a `CoverageSpan` may represent multiple
|
|
// `Statement`s and/or `Terminator`s.)
|
|
fn bcb_to_initial_coverage_spans(
|
|
&self,
|
|
bcb: BasicCoverageBlock,
|
|
bcb_data: &'a BasicCoverageBlockData,
|
|
) -> Vec<CoverageSpan> {
|
|
bcb_data
|
|
.basic_blocks
|
|
.iter()
|
|
.flat_map(|&bb| {
|
|
let data = &self.mir_body[bb];
|
|
data.statements
|
|
.iter()
|
|
.enumerate()
|
|
.filter_map(move |(index, statement)| {
|
|
filtered_statement_span(statement, self.body_span).map(|span| {
|
|
CoverageSpan::for_statement(statement, span, bcb, bb, index)
|
|
})
|
|
})
|
|
.chain(
|
|
filtered_terminator_span(data.terminator(), self.body_span)
|
|
.map(|span| CoverageSpan::for_terminator(span, bcb, bb)),
|
|
)
|
|
})
|
|
.collect()
|
|
}
|
|
|
|
fn curr(&self) -> &CoverageSpan {
|
|
self.some_curr
|
|
.as_ref()
|
|
.unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_curr"))
|
|
}
|
|
|
|
fn curr_mut(&mut self) -> &mut CoverageSpan {
|
|
self.some_curr
|
|
.as_mut()
|
|
.unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_curr"))
|
|
}
|
|
|
|
fn prev(&self) -> &CoverageSpan {
|
|
self.some_prev
|
|
.as_ref()
|
|
.unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_prev"))
|
|
}
|
|
|
|
fn prev_mut(&mut self) -> &mut CoverageSpan {
|
|
self.some_prev
|
|
.as_mut()
|
|
.unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_prev"))
|
|
}
|
|
|
|
fn take_prev(&mut self) -> CoverageSpan {
|
|
self.some_prev.take().unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_prev"))
|
|
}
|
|
|
|
/// If there are `pending_dups` but `prev` is not a matching dup (`prev.span` doesn't match the
|
|
/// `pending_dups` spans), then one of the following two things happened during the previous
|
|
/// iteration:
|
|
/// * the previous `curr` span (which is now `prev`) was not a duplicate of the pending_dups
|
|
/// (in which case there should be at least two spans in `pending_dups`); or
|
|
/// * the `span` of `prev` was modified by `curr_mut().merge_from(prev)` (in which case
|
|
/// `pending_dups` could have as few as one span)
|
|
/// In either case, no more spans will match the span of `pending_dups`, so
|
|
/// add the `pending_dups` if they don't overlap `curr`, and clear the list.
|
|
fn check_pending_dups(&mut self) {
|
|
if let Some(dup) = self.pending_dups.last() {
|
|
if dup.span != self.prev().span {
|
|
debug!(
|
|
" SAME spans, but pending_dups are NOT THE SAME, so BCBs matched on \
|
|
previous iteration, or prev started a new disjoint span"
|
|
);
|
|
if dup.span.hi() <= self.curr().span.lo() {
|
|
let pending_dups = self.pending_dups.split_off(0);
|
|
for dup in pending_dups.into_iter() {
|
|
debug!(" ...adding at least one pending={:?}", dup);
|
|
self.refined_spans.push(dup);
|
|
}
|
|
} else {
|
|
self.pending_dups.clear();
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Advance `prev` to `curr` (if any), and `curr` to the next `CoverageSpan` in sorted order.
|
|
fn next_coverage_span(&mut self) -> bool {
|
|
if let Some(curr) = self.some_curr.take() {
|
|
self.some_prev = Some(curr);
|
|
self.prev_original_span = self.curr_original_span;
|
|
}
|
|
while let Some(curr) = self.sorted_spans_iter.as_mut().unwrap().next() {
|
|
debug!("FOR curr={:?}", curr);
|
|
if self.prev_starts_after_next(&curr) {
|
|
debug!(
|
|
" prev.span starts after curr.span, so curr will be dropped (skipping past \
|
|
closure?); prev={:?}",
|
|
self.prev()
|
|
);
|
|
} else {
|
|
// Save a copy of the original span for `curr` in case the `CoverageSpan` is changed
|
|
// by `self.curr_mut().merge_from(prev)`.
|
|
self.curr_original_span = curr.span;
|
|
self.some_curr.replace(curr);
|
|
self.check_pending_dups();
|
|
return true;
|
|
}
|
|
}
|
|
false
|
|
}
|
|
|
|
/// If called, then the next call to `next_coverage_span()` will *not* update `prev` with the
|
|
/// `curr` coverage span.
|
|
fn take_curr(&mut self) -> CoverageSpan {
|
|
self.some_curr.take().unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_curr"))
|
|
}
|
|
|
|
/// Returns true if the curr span should be skipped because prev has already advanced beyond the
|
|
/// end of curr. This can only happen if a prior iteration updated `prev` to skip past a region
|
|
/// of code, such as skipping past a closure.
|
|
fn prev_starts_after_next(&self, next_curr: &CoverageSpan) -> bool {
|
|
self.prev().span.lo() > next_curr.span.lo()
|
|
}
|
|
|
|
/// Returns true if the curr span starts past the end of the prev span, which means they don't
|
|
/// overlap, so we now know the prev can be added to the refined coverage spans.
|
|
fn prev_ends_before_curr(&self) -> bool {
|
|
self.prev().span.hi() <= self.curr().span.lo()
|
|
}
|
|
|
|
/// If `prev`s span extends left of the closure (`curr`), carve out the closure's span from
|
|
/// `prev`'s span. (The closure's coverage counters will be injected when processing the
|
|
/// closure's own MIR.) Add the portion of the span to the left of the closure; and if the span
|
|
/// extends to the right of the closure, update `prev` to that portion of the span. For any
|
|
/// `pending_dups`, repeat the same process.
|
|
fn carve_out_span_for_closure(&mut self) {
|
|
let curr_span = self.curr().span;
|
|
let left_cutoff = curr_span.lo();
|
|
let right_cutoff = curr_span.hi();
|
|
let has_pre_closure_span = self.prev().span.lo() < right_cutoff;
|
|
let has_post_closure_span = self.prev().span.hi() > right_cutoff;
|
|
let mut pending_dups = self.pending_dups.split_off(0);
|
|
if has_pre_closure_span {
|
|
let mut pre_closure = self.prev().clone();
|
|
pre_closure.span = pre_closure.span.with_hi(left_cutoff);
|
|
debug!(" prev overlaps a closure. Adding span for pre_closure={:?}", pre_closure);
|
|
if !pending_dups.is_empty() {
|
|
for mut dup in pending_dups.iter().cloned() {
|
|
dup.span = dup.span.with_hi(left_cutoff);
|
|
debug!(" ...and at least one pre_closure dup={:?}", dup);
|
|
self.refined_spans.push(dup);
|
|
}
|
|
}
|
|
self.refined_spans.push(pre_closure);
|
|
}
|
|
if has_post_closure_span {
|
|
// Update prev.span to start after the closure (and discard curr)
|
|
self.prev_mut().span = self.prev().span.with_lo(right_cutoff);
|
|
self.prev_original_span = self.prev().span;
|
|
for dup in pending_dups.iter_mut() {
|
|
dup.span = dup.span.with_lo(right_cutoff);
|
|
}
|
|
self.pending_dups.append(&mut pending_dups);
|
|
let closure_covspan = self.take_curr();
|
|
self.refined_spans.push(closure_covspan); // since self.prev() was already updated
|
|
} else {
|
|
pending_dups.clear();
|
|
}
|
|
}
|
|
|
|
/// Called if `curr.span` equals `prev_original_span` (and potentially equal to all
|
|
/// `pending_dups` spans, if any); but keep in mind, `prev.span` may start at a `Span.lo()` that
|
|
/// is less than (further left of) `prev_original_span.lo()`.
|
|
///
|
|
/// When two `CoverageSpan`s have the same `Span`, dominated spans can be discarded; but if
|
|
/// neither `CoverageSpan` dominates the other, both (or possibly more than two) are held,
|
|
/// until their disposition is determined. In this latter case, the `prev` dup is moved into
|
|
/// `pending_dups` so the new `curr` dup can be moved to `prev` for the next iteration.
|
|
fn hold_pending_dups_unless_dominated(&mut self) {
|
|
// Equal coverage spans are ordered by dominators before dominated (if any), so it should be
|
|
// impossible for `curr` to dominate any previous `CoverageSpan`.
|
|
debug_assert!(!self.span_bcb_is_dominated_by(self.prev(), self.curr()));
|
|
|
|
let initial_pending_count = self.pending_dups.len();
|
|
if initial_pending_count > 0 {
|
|
let mut pending_dups = self.pending_dups.split_off(0);
|
|
pending_dups.retain(|dup| !self.span_bcb_is_dominated_by(self.curr(), dup));
|
|
self.pending_dups.append(&mut pending_dups);
|
|
if self.pending_dups.len() < initial_pending_count {
|
|
debug!(
|
|
" discarded {} of {} pending_dups that dominated curr",
|
|
initial_pending_count - self.pending_dups.len(),
|
|
initial_pending_count
|
|
);
|
|
}
|
|
}
|
|
|
|
if self.span_bcb_is_dominated_by(self.curr(), self.prev()) {
|
|
debug!(
|
|
" different bcbs but SAME spans, and prev dominates curr. Discard prev={:?}",
|
|
self.prev()
|
|
);
|
|
self.cutoff_prev_at_overlapping_curr();
|
|
// If one span dominates the other, assocate the span with the code from the dominated
|
|
// block only (`curr`), and discard the overlapping portion of the `prev` span. (Note
|
|
// that if `prev.span` is wider than `prev_original_span`, a `CoverageSpan` will still
|
|
// be created for `prev`s block, for the non-overlapping portion, left of `curr.span`.)
|
|
//
|
|
// For example:
|
|
// match somenum {
|
|
// x if x < 1 => { ... }
|
|
// }...
|
|
//
|
|
// The span for the first `x` is referenced by both the pattern block (every time it is
|
|
// evaluated) and the arm code (only when matched). The counter will be applied only to
|
|
// the dominated block. This allows coverage to track and highlight things like the
|
|
// assignment of `x` above, if the branch is matched, making `x` available to the arm
|
|
// code; and to track and highlight the question mark `?` "try" operator at the end of
|
|
// a function call returning a `Result`, so the `?` is covered when the function returns
|
|
// an `Err`, and not counted as covered if the function always returns `Ok`.
|
|
} else {
|
|
// Save `prev` in `pending_dups`. (`curr` will become `prev` in the next iteration.)
|
|
// If the `curr` CoverageSpan is later discarded, `pending_dups` can be discarded as
|
|
// well; but if `curr` is added to refined_spans, the `pending_dups` will also be added.
|
|
debug!(
|
|
" different bcbs but SAME spans, and neither dominates, so keep curr for \
|
|
next iter, and, pending upcoming spans (unless overlapping) add prev={:?}",
|
|
self.prev()
|
|
);
|
|
let prev = self.take_prev();
|
|
self.pending_dups.push(prev);
|
|
}
|
|
}
|
|
|
|
/// `curr` overlaps `prev`. If `prev`s span extends left of `curr`s span, keep _only_
|
|
/// statements that end before `curr.lo()` (if any), and add the portion of the
|
|
/// combined span for those statements. Any other statements have overlapping spans
|
|
/// that can be ignored because `curr` and/or other upcoming statements/spans inside
|
|
/// the overlap area will produce their own counters. This disambiguation process
|
|
/// avoids injecting multiple counters for overlapping spans, and the potential for
|
|
/// double-counting.
|
|
fn cutoff_prev_at_overlapping_curr(&mut self) {
|
|
debug!(
|
|
" different bcbs, overlapping spans, so ignore/drop pending and only add prev \
|
|
if it has statements that end before curr; prev={:?}",
|
|
self.prev()
|
|
);
|
|
if self.pending_dups.is_empty() {
|
|
let curr_span = self.curr().span;
|
|
self.prev_mut().cutoff_statements_at(curr_span.lo());
|
|
if self.prev().coverage_statements.is_empty() {
|
|
debug!(" ... no non-overlapping statements to add");
|
|
} else {
|
|
debug!(" ... adding modified prev={:?}", self.prev());
|
|
let prev = self.take_prev();
|
|
self.refined_spans.push(prev);
|
|
}
|
|
} else {
|
|
// with `pending_dups`, `prev` cannot have any statements that don't overlap
|
|
self.pending_dups.clear();
|
|
}
|
|
}
|
|
|
|
fn span_bcb_is_dominated_by(&self, covspan: &CoverageSpan, dom_covspan: &CoverageSpan) -> bool {
|
|
self.basic_coverage_blocks.is_dominated_by(covspan.bcb, dom_covspan.bcb)
|
|
}
|
|
}
|
|
|
|
pub(super) fn filtered_statement_span(
|
|
statement: &'a Statement<'tcx>,
|
|
body_span: Span,
|
|
) -> Option<Span> {
|
|
match statement.kind {
|
|
// These statements have spans that are often outside the scope of the executed source code
|
|
// for their parent `BasicBlock`.
|
|
StatementKind::StorageLive(_)
|
|
| StatementKind::StorageDead(_)
|
|
// Coverage should not be encountered, but don't inject coverage coverage
|
|
| StatementKind::Coverage(_)
|
|
// Ignore `Nop`s
|
|
| StatementKind::Nop => None,
|
|
|
|
// FIXME(#78546): MIR InstrumentCoverage - Can the source_info.span for `FakeRead`
|
|
// statements be more consistent?
|
|
//
|
|
// FakeReadCause::ForGuardBinding, in this example:
|
|
// match somenum {
|
|
// x if x < 1 => { ... }
|
|
// }...
|
|
// The BasicBlock within the match arm code included one of these statements, but the span
|
|
// for it covered the `1` in this source. The actual statements have nothing to do with that
|
|
// source span:
|
|
// FakeRead(ForGuardBinding, _4);
|
|
// where `_4` is:
|
|
// _4 = &_1; (at the span for the first `x`)
|
|
// and `_1` is the `Place` for `somenum`.
|
|
//
|
|
// If and when the Issue is resolved, remove this special case match pattern:
|
|
StatementKind::FakeRead(cause, _) if cause == FakeReadCause::ForGuardBinding => None,
|
|
|
|
// Retain spans from all other statements
|
|
StatementKind::FakeRead(_, _) // Not including `ForGuardBinding`
|
|
| StatementKind::Assign(_)
|
|
| StatementKind::SetDiscriminant { .. }
|
|
| StatementKind::LlvmInlineAsm(_)
|
|
| StatementKind::Retag(_, _)
|
|
| StatementKind::AscribeUserType(_, _) => {
|
|
Some(function_source_span(statement.source_info.span, body_span))
|
|
}
|
|
}
|
|
}
|
|
|
|
pub(super) fn filtered_terminator_span(
|
|
terminator: &'a Terminator<'tcx>,
|
|
body_span: Span,
|
|
) -> Option<Span> {
|
|
match terminator.kind {
|
|
// These terminators have spans that don't positively contribute to computing a reasonable
|
|
// span of actually executed source code. (For example, SwitchInt terminators extracted from
|
|
// an `if condition { block }` has a span that includes the executed block, if true,
|
|
// but for coverage, the code region executed, up to *and* through the SwitchInt,
|
|
// actually stops before the if's block.)
|
|
TerminatorKind::Unreachable // Unreachable blocks are not connected to the MIR CFG
|
|
| TerminatorKind::Assert { .. }
|
|
| TerminatorKind::Drop { .. }
|
|
| TerminatorKind::DropAndReplace { .. }
|
|
| TerminatorKind::SwitchInt { .. }
|
|
// For `FalseEdge`, only the `real` branch is taken, so it is similar to a `Goto`.
|
|
| TerminatorKind::FalseEdge { .. }
|
|
| TerminatorKind::Goto { .. } => None,
|
|
|
|
// Retain spans from all other terminators
|
|
TerminatorKind::Resume
|
|
| TerminatorKind::Abort
|
|
| TerminatorKind::Return
|
|
| TerminatorKind::Call { .. }
|
|
| TerminatorKind::Yield { .. }
|
|
| TerminatorKind::GeneratorDrop
|
|
| TerminatorKind::FalseUnwind { .. }
|
|
| TerminatorKind::InlineAsm { .. } => {
|
|
Some(function_source_span(terminator.source_info.span, body_span))
|
|
}
|
|
}
|
|
}
|
|
|
|
#[inline]
|
|
fn function_source_span(span: Span, body_span: Span) -> Span {
|
|
let span = original_sp(span, body_span).with_ctxt(SyntaxContext::root());
|
|
if body_span.contains(span) { span } else { body_span }
|
|
}
|