diff options
Diffstat (limited to 'compiler/rustc_mir_transform/src')
| -rw-r--r-- | compiler/rustc_mir_transform/src/coroutine.rs | 44 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/coverage/spans.rs | 47 | ||||
| -rw-r--r-- | compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs | 25 |
3 files changed, 71 insertions, 45 deletions
diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs index 2b591abb05d..737fb6bf612 100644 --- a/compiler/rustc_mir_transform/src/coroutine.rs +++ b/compiler/rustc_mir_transform/src/coroutine.rs @@ -252,15 +252,15 @@ struct TransformVisitor<'tcx> { impl<'tcx> TransformVisitor<'tcx> { fn insert_none_ret_block(&self, body: &mut Body<'tcx>) -> BasicBlock { - assert!(matches!(self.coroutine_kind, CoroutineKind::Gen(_))); - let block = BasicBlock::new(body.basic_blocks.len()); let source_info = SourceInfo::outermost(body.span); - let option_def_id = self.tcx.require_lang_item(LangItem::Option, None); - let statements = vec![Statement { - kind: StatementKind::Assign(Box::new(( - Place::return_place(), + let none_value = match self.coroutine_kind { + CoroutineKind::Async(_) => span_bug!(body.span, "`Future`s are not fused inherently"), + CoroutineKind::Coroutine => span_bug!(body.span, "`Coroutine`s cannot be fused"), + // `gen` continues return `None` + CoroutineKind::Gen(_) => { + let option_def_id = self.tcx.require_lang_item(LangItem::Option, None); Rvalue::Aggregate( Box::new(AggregateKind::Adt( option_def_id, @@ -270,8 +270,29 @@ impl<'tcx> TransformVisitor<'tcx> { None, )), IndexVec::new(), - ), - ))), + ) + } + // `async gen` continues to return `Poll::Ready(None)` + CoroutineKind::AsyncGen(_) => { + let ty::Adt(_poll_adt, args) = *self.old_yield_ty.kind() else { bug!() }; + let ty::Adt(_option_adt, args) = *args.type_at(0).kind() else { bug!() }; + let yield_ty = args.type_at(0); + Rvalue::Use(Operand::Constant(Box::new(ConstOperand { + span: source_info.span, + const_: Const::Unevaluated( + UnevaluatedConst::new( + self.tcx.require_lang_item(LangItem::AsyncGenFinished, None), + self.tcx.mk_args(&[yield_ty.into()]), + ), + self.old_yield_ty, + ), + user_ty: None, + }))) + } + }; + + let statements = vec![Statement { + kind: StatementKind::Assign(Box::new((Place::return_place(), none_value))), source_info, }]; @@ -1393,11 +1414,12 @@ fn create_coroutine_resume_function<'tcx>( if can_return { let block = match coroutine_kind { - // FIXME(gen_blocks): Should `async gen` yield `None` when resumed once again? - CoroutineKind::Async(_) | CoroutineKind::AsyncGen(_) | CoroutineKind::Coroutine => { + CoroutineKind::Async(_) | CoroutineKind::Coroutine => { insert_panic_block(tcx, body, ResumedAfterReturn(coroutine_kind)) } - CoroutineKind::Gen(_) => transform.insert_none_ret_block(body), + CoroutineKind::AsyncGen(_) | CoroutineKind::Gen(_) => { + transform.insert_none_ret_block(body) + } }; cases.insert(1, (RETURNED, block)); } diff --git a/compiler/rustc_mir_transform/src/coverage/spans.rs b/compiler/rustc_mir_transform/src/coverage/spans.rs index c415a832994..05ad14f1525 100644 --- a/compiler/rustc_mir_transform/src/coverage/spans.rs +++ b/compiler/rustc_mir_transform/src/coverage/spans.rs @@ -319,29 +319,16 @@ impl<'a> CoverageSpansGenerator<'a> { } } - let prev = self.take_prev(); - debug!(" AT END, adding last prev={prev:?}"); - // Drain any remaining dups into the output. for dup in self.pending_dups.drain(..) { debug!(" ...adding at least one pending dup={:?}", dup); self.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) = self.refined_spans.last() { - last_covspan.is_closure && last_covspan.span.hi() == self.body_span.hi() - } else { - false - }; - - if !body_ends_with_closure { + // There is usually a final span remaining in `prev` after the loop ends, + // so add it to the output as well. + if let Some(prev) = self.some_prev.take() { + debug!(" AT END, adding last prev={prev:?}"); self.refined_spans.push(prev); } @@ -398,38 +385,36 @@ impl<'a> CoverageSpansGenerator<'a> { self.refined_spans.push(macro_name_cov); } + #[track_caller] fn curr(&self) -> &CoverageSpan { - self.some_curr - .as_ref() - .unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_curr")) + self.some_curr.as_ref().unwrap_or_else(|| bug!("some_curr is None (curr)")) } + #[track_caller] fn curr_mut(&mut self) -> &mut CoverageSpan { - self.some_curr - .as_mut() - .unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_curr")) + self.some_curr.as_mut().unwrap_or_else(|| bug!("some_curr is None (curr_mut)")) } /// If called, then the next call to `next_coverage_span()` will *not* update `prev` with the /// `curr` coverage span. + #[track_caller] fn take_curr(&mut self) -> CoverageSpan { - self.some_curr.take().unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_curr")) + self.some_curr.take().unwrap_or_else(|| bug!("some_curr is None (take_curr)")) } + #[track_caller] fn prev(&self) -> &CoverageSpan { - self.some_prev - .as_ref() - .unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_prev")) + self.some_prev.as_ref().unwrap_or_else(|| bug!("some_prev is None (prev)")) } + #[track_caller] fn prev_mut(&mut self) -> &mut CoverageSpan { - self.some_prev - .as_mut() - .unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_prev")) + self.some_prev.as_mut().unwrap_or_else(|| bug!("some_prev is None (prev_mut)")) } + #[track_caller] fn take_prev(&mut self) -> CoverageSpan { - self.some_prev.take().unwrap_or_else(|| bug!("invalid attempt to unwrap a None some_prev")) + self.some_prev.take().unwrap_or_else(|| bug!("some_prev is None (take_prev)")) } /// If there are `pending_dups` but `prev` is not a matching dup (`prev.span` doesn't match the diff --git a/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs b/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs index e1531f2c239..eab9a9c98f8 100644 --- a/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs +++ b/compiler/rustc_mir_transform/src/coverage/spans/from_mir.rs @@ -44,6 +44,16 @@ pub(super) fn mir_to_initial_sorted_coverage_spans( .then_with(|| Ord::cmp(&a.is_closure, &b.is_closure).reverse()) }); + // The desugaring of an async function includes a closure containing the + // original function body, and a terminator that returns the `impl Future`. + // That terminator will cause a confusing coverage count for the function's + // closing brace, so discard everything after the body closure span. + if let Some(body_closure_index) = + initial_spans.iter().rposition(|covspan| covspan.is_closure && covspan.span == body_span) + { + initial_spans.truncate(body_closure_index + 1); + } + initial_spans } @@ -92,13 +102,13 @@ fn is_closure(statement: &Statement<'_>) -> bool { /// If the MIR `Statement` has a span contributive to computing coverage spans, /// return it; otherwise return `None`. fn filtered_statement_span(statement: &Statement<'_>) -> Option<Span> { + use mir::coverage::CoverageKind; + 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 `ConstEvalCounter`s | StatementKind::ConstEvalCounter // Ignore `Nop`s @@ -122,9 +132,13 @@ fn filtered_statement_span(statement: &Statement<'_>) -> Option<Span> { // If and when the Issue is resolved, remove this special case match pattern: StatementKind::FakeRead(box (FakeReadCause::ForGuardBinding, _)) => None, - // Retain spans from all other statements + // Retain spans from most other statements. StatementKind::FakeRead(box (_, _)) // Not including `ForGuardBinding` | StatementKind::Intrinsic(..) + | StatementKind::Coverage(box mir::Coverage { + // The purpose of `SpanMarker` is to be matched and accepted here. + kind: CoverageKind::SpanMarker + }) | StatementKind::Assign(_) | StatementKind::SetDiscriminant { .. } | StatementKind::Deinit(..) @@ -133,6 +147,11 @@ fn filtered_statement_span(statement: &Statement<'_>) -> Option<Span> { | StatementKind::AscribeUserType(_, _) => { Some(statement.source_info.span) } + + StatementKind::Coverage(box mir::Coverage { + // These coverage statements should not exist prior to coverage instrumentation. + kind: CoverageKind::CounterIncrement { .. } | CoverageKind::ExpressionUsed { .. } + }) => bug!("Unexpected coverage statement found during coverage instrumentation: {statement:?}"), } } |