From 81ed042c8cc4a1bd677c9209cf9edca6b91af04a Mon Sep 17 00:00:00 2001 From: Zalathar Date: Wed, 6 Aug 2025 22:02:01 +1000 Subject: coverage: Remove all unstable support for MC/DC instrumentation --- compiler/rustc_mir_transform/src/coverage/mod.rs | 119 +---------------------- 1 file changed, 2 insertions(+), 117 deletions(-) (limited to 'compiler/rustc_mir_transform/src/coverage/mod.rs') diff --git a/compiler/rustc_mir_transform/src/coverage/mod.rs b/compiler/rustc_mir_transform/src/coverage/mod.rs index f253d1662ca..f6945a95a7c 100644 --- a/compiler/rustc_mir_transform/src/coverage/mod.rs +++ b/compiler/rustc_mir_transform/src/coverage/mod.rs @@ -10,9 +10,7 @@ mod unexpand; use rustc_hir as hir; use rustc_hir::intravisit::{Visitor, walk_expr}; use rustc_middle::hir::nested_filter; -use rustc_middle::mir::coverage::{ - CoverageKind, DecisionInfo, FunctionCoverageInfo, Mapping, MappingKind, -}; +use rustc_middle::mir::coverage::{CoverageKind, FunctionCoverageInfo, Mapping, MappingKind}; use rustc_middle::mir::{self, BasicBlock, Statement, StatementKind, TerminatorKind}; use rustc_middle::ty::TyCtxt; use rustc_span::Span; @@ -95,14 +93,6 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir: // Inject coverage statements into MIR. inject_coverage_statements(mir_body, &graph); - inject_mcdc_statements(mir_body, &graph, &extracted_mappings); - - let mcdc_num_condition_bitmaps = extracted_mappings - .mcdc_mappings - .iter() - .map(|&(mappings::MCDCDecision { decision_depth, .. }, _)| decision_depth) - .max() - .map_or(0, |max| usize::from(max) + 1); mir_body.function_coverage_info = Some(Box::new(FunctionCoverageInfo { function_source_hash: hir_info.function_source_hash, @@ -111,9 +101,6 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir: priority_list, mappings, - - mcdc_bitmap_bits: extracted_mappings.mcdc_bitmap_bits, - mcdc_num_condition_bitmaps, })); } @@ -124,13 +111,7 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir: /// function can potentially be simplified even further. fn create_mappings(extracted_mappings: &ExtractedMappings) -> Vec { // Fully destructure the mappings struct to make sure we don't miss any kinds. - let ExtractedMappings { - code_mappings, - branch_pairs, - mcdc_bitmap_bits: _, - mcdc_degraded_branches, - mcdc_mappings, - } = extracted_mappings; + let ExtractedMappings { code_mappings, branch_pairs } = extracted_mappings; let mut mappings = Vec::new(); mappings.extend(code_mappings.iter().map( @@ -148,57 +129,6 @@ fn create_mappings(extracted_mappings: &ExtractedMappings) -> Vec { }, )); - // MCDC branch mappings are appended with their decisions in case decisions were ignored. - mappings.extend(mcdc_degraded_branches.iter().map( - |&mappings::MCDCBranch { - span, - true_bcb, - false_bcb, - condition_info: _, - true_index: _, - false_index: _, - }| { Mapping { kind: MappingKind::Branch { true_bcb, false_bcb }, span } }, - )); - - for (decision, branches) in mcdc_mappings { - // FIXME(#134497): Previously it was possible for some of these branch - // conversions to fail, in which case the remaining branches in the - // decision would be degraded to plain `MappingKind::Branch`. - // The changes in #134497 made that failure impossible, because the - // fallible step was deferred to codegen. But the corresponding code - // in codegen wasn't updated to detect the need for a degrade step. - let conditions = branches - .into_iter() - .map( - |&mappings::MCDCBranch { - span, - true_bcb, - false_bcb, - condition_info, - true_index: _, - false_index: _, - }| { - Mapping { - kind: MappingKind::MCDCBranch { - true_bcb, - false_bcb, - mcdc_params: condition_info, - }, - span, - } - }, - ) - .collect::>(); - - // LLVM requires end index for counter mapping regions. - let kind = MappingKind::MCDCDecision(DecisionInfo { - bitmap_idx: (decision.bitmap_idx + decision.num_test_vectors) as u32, - num_conditions: u16::try_from(conditions.len()).unwrap(), - }); - let span = decision.span; - mappings.extend(std::iter::once(Mapping { kind, span }).chain(conditions.into_iter())); - } - mappings } @@ -210,51 +140,6 @@ fn inject_coverage_statements<'tcx>(mir_body: &mut mir::Body<'tcx>, graph: &Cove } } -/// For each conditions inject statements to update condition bitmap after it has been evaluated. -/// For each decision inject statements to update test vector bitmap after it has been evaluated. -fn inject_mcdc_statements<'tcx>( - mir_body: &mut mir::Body<'tcx>, - graph: &CoverageGraph, - extracted_mappings: &ExtractedMappings, -) { - for (decision, conditions) in &extracted_mappings.mcdc_mappings { - // Inject test vector update first because `inject_statement` always insert new statement at head. - for &end in &decision.end_bcbs { - let end_bb = graph[end].leader_bb(); - inject_statement( - mir_body, - CoverageKind::TestVectorBitmapUpdate { - bitmap_idx: decision.bitmap_idx as u32, - decision_depth: decision.decision_depth, - }, - end_bb, - ); - } - - for &mappings::MCDCBranch { - span: _, - true_bcb, - false_bcb, - condition_info: _, - true_index, - false_index, - } in conditions - { - for (index, bcb) in [(false_index, false_bcb), (true_index, true_bcb)] { - let bb = graph[bcb].leader_bb(); - inject_statement( - mir_body, - CoverageKind::CondBitmapUpdate { - index: index as u32, - decision_depth: decision.decision_depth, - }, - bb, - ); - } - } - } -} - fn inject_statement(mir_body: &mut mir::Body<'_>, counter_kind: CoverageKind, bb: BasicBlock) { debug!(" injecting statement {counter_kind:?} for {bb:?}"); let data = &mut mir_body[bb]; -- cgit 1.4.1-3-g733a5