Auto merge of #3751 - rust-lang:rustup-2024-07-16, r=RalfJung

Automatic Rustup

6 files changed, 48 insertions, 21 deletions

diff --git a/compiler/rustc_mir_transform/src/coroutine.rs b/compiler/rustc_mir_transform/src/coroutine.rs
index fa5da89e8ba..261dcd52d71 100644
--- a/compiler/rustc_mir_transform/src/coroutine.rs
+++ b/compiler/rustc_mir_transform/src/coroutine.rs
@@ -81,8 +81,8 @@ use rustc_span::symbol::sym;
 use rustc_span::Span;
 use rustc_target::abi::{FieldIdx, VariantIdx};
 use rustc_target::spec::PanicStrategy;
+use rustc_trait_selection::error_reporting::traits::TypeErrCtxtExt as _;
 use rustc_trait_selection::infer::TyCtxtInferExt as _;
-use rustc_trait_selection::traits::error_reporting::TypeErrCtxtExt as _;
 use rustc_trait_selection::traits::ObligationCtxt;
 use rustc_trait_selection::traits::{ObligationCause, ObligationCauseCode};
 use std::{iter, ops};
diff --git a/compiler/rustc_mir_transform/src/coverage/mappings.rs b/compiler/rustc_mir_transform/src/coverage/mappings.rs
index 25297245172..2ac08ea85d2 100644
--- a/compiler/rustc_mir_transform/src/coverage/mappings.rs
+++ b/compiler/rustc_mir_transform/src/coverage/mappings.rs
@@ -56,6 +56,10 @@ pub(super) struct MCDCDecision {
 
 #[derive(Default)]
 pub(super) struct ExtractedMappings {
+    /// Store our own copy of [`CoverageGraph::num_nodes`], so that we don't
+    /// need access to the whole graph when allocating per-BCB data. This is
+    /// only public so that other code can still use exhaustive destructuring.
+    pub(super) num_bcbs: usize,
     pub(super) code_mappings: Vec<CodeMapping>,
     pub(super) branch_pairs: Vec<BranchPair>,
     pub(super) mcdc_bitmap_bytes: u32,
@@ -106,6 +110,7 @@ pub(super) fn extract_all_mapping_info_from_mir<'tcx>(
     );
 
     ExtractedMappings {
+        num_bcbs: basic_coverage_blocks.num_nodes(),
         code_mappings,
         branch_pairs,
         mcdc_bitmap_bytes,
@@ -115,12 +120,10 @@ pub(super) fn extract_all_mapping_info_from_mir<'tcx>(
 }
 
 impl ExtractedMappings {
-    pub(super) fn all_bcbs_with_counter_mappings(
-        &self,
-        basic_coverage_blocks: &CoverageGraph, // Only used for allocating a correctly-sized set
-    ) -> BitSet<BasicCoverageBlock> {
+    pub(super) fn all_bcbs_with_counter_mappings(&self) -> BitSet<BasicCoverageBlock> {
         // Fully destructure self to make sure we don't miss any fields that have mappings.
         let Self {
+            num_bcbs,
             code_mappings,
             branch_pairs,
             mcdc_bitmap_bytes: _,
@@ -129,7 +132,7 @@ impl ExtractedMappings {
         } = self;
 
         // Identify which BCBs have one or more mappings.
-        let mut bcbs_with_counter_mappings = BitSet::new_empty(basic_coverage_blocks.num_nodes());
+        let mut bcbs_with_counter_mappings = BitSet::new_empty(*num_bcbs);
         let mut insert = |bcb| {
             bcbs_with_counter_mappings.insert(bcb);
         };
@@ -156,6 +159,15 @@ impl ExtractedMappings {
 
         bcbs_with_counter_mappings
     }
+
+    /// Returns the set of BCBs that have one or more `Code` mappings.
+    pub(super) fn bcbs_with_ordinary_code_mappings(&self) -> BitSet<BasicCoverageBlock> {
+        let mut bcbs = BitSet::new_empty(self.num_bcbs);
+        for &CodeMapping { span: _, bcb } in &self.code_mappings {
+            bcbs.insert(bcb);
+        }
+        bcbs
+    }
 }
 
 fn resolve_block_markers(
diff --git a/compiler/rustc_mir_transform/src/coverage/mod.rs b/compiler/rustc_mir_transform/src/coverage/mod.rs
index 2efca40d180..3772a8f5118 100644
--- a/compiler/rustc_mir_transform/src/coverage/mod.rs
+++ b/compiler/rustc_mir_transform/src/coverage/mod.rs
@@ -25,7 +25,7 @@ use rustc_span::source_map::SourceMap;
 use rustc_span::{BytePos, Pos, RelativeBytePos, Span, Symbol};
 
 use crate::coverage::counters::{CounterIncrementSite, CoverageCounters};
-use crate::coverage::graph::{BasicCoverageBlock, CoverageGraph};
+use crate::coverage::graph::CoverageGraph;
 use crate::coverage::mappings::ExtractedMappings;
 use crate::MirPass;
 
@@ -88,8 +88,7 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir:
     // every coverage span has a `Counter` or `Expression` assigned to its `BasicCoverageBlock`
     // and all `Expression` dependencies (operands) are also generated, for any other
     // `BasicCoverageBlock`s not already associated with a coverage span.
-    let bcbs_with_counter_mappings =
-        extracted_mappings.all_bcbs_with_counter_mappings(&basic_coverage_blocks);
+    let bcbs_with_counter_mappings = extracted_mappings.all_bcbs_with_counter_mappings();
     if bcbs_with_counter_mappings.is_empty() {
         // No relevant spans were found in MIR, so skip instrumenting this function.
         return;
@@ -109,7 +108,7 @@ fn instrument_function_for_coverage<'tcx>(tcx: TyCtxt<'tcx>, mir_body: &mut mir:
     inject_coverage_statements(
         mir_body,
         &basic_coverage_blocks,
-        bcb_has_counter_mappings,
+        &extracted_mappings,
         &coverage_counters,
     );
 
@@ -163,6 +162,7 @@ fn create_mappings<'tcx>(
 
     // Fully destructure the mappings struct to make sure we don't miss any kinds.
     let ExtractedMappings {
+        num_bcbs: _,
         code_mappings,
         branch_pairs,
         mcdc_bitmap_bytes: _,
@@ -219,7 +219,7 @@ fn create_mappings<'tcx>(
 fn inject_coverage_statements<'tcx>(
     mir_body: &mut mir::Body<'tcx>,
     basic_coverage_blocks: &CoverageGraph,
-    bcb_has_coverage_spans: impl Fn(BasicCoverageBlock) -> bool,
+    extracted_mappings: &ExtractedMappings,
     coverage_counters: &CoverageCounters,
 ) {
     // Inject counter-increment statements into MIR.
@@ -252,11 +252,16 @@ fn inject_coverage_statements<'tcx>(
     // can check whether the injected statement survived MIR optimization.
     // (BCB edges can't have spans, so we only need to process BCB nodes here.)
     //
+    // We only do this for ordinary `Code` mappings, because branch and MC/DC
+    // mappings might have expressions that don't correspond to any single
+    // point in the control-flow graph.
+    //
     // See the code in `rustc_codegen_llvm::coverageinfo::map_data` that deals
     // with "expressions seen" and "zero terms".
+    let eligible_bcbs = extracted_mappings.bcbs_with_ordinary_code_mappings();
     for (bcb, expression_id) in coverage_counters
         .bcb_nodes_with_coverage_expressions()
-        .filter(|&(bcb, _)| bcb_has_coverage_spans(bcb))
+        .filter(|&(bcb, _)| eligible_bcbs.contains(bcb))
     {
         inject_statement(
             mir_body,
diff --git a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
index 8b965f4d18e..8303ef039d1 100644
--- a/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
+++ b/compiler/rustc_mir_transform/src/dataflow_const_prop.rs
@@ -66,7 +66,7 @@ impl<'tcx> MirPass<'tcx> for DataflowConstProp {
 }
 
 struct ConstAnalysis<'a, 'tcx> {
-    map: Map,
+    map: Map<'tcx>,
     tcx: TyCtxt<'tcx>,
     local_decls: &'a LocalDecls<'tcx>,
     ecx: InterpCx<'tcx, DummyMachine>,
@@ -78,7 +78,7 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'_, 'tcx> {
 
     const NAME: &'static str = "ConstAnalysis";
 
-    fn map(&self) -> &Map {
+    fn map(&self) -> &Map<'tcx> {
         &self.map
     }
 
@@ -330,7 +330,7 @@ impl<'tcx> ValueAnalysis<'tcx> for ConstAnalysis<'_, 'tcx> {
 }
 
 impl<'a, 'tcx> ConstAnalysis<'a, 'tcx> {
-    pub fn new(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, map: Map) -> Self {
+    pub fn new(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, map: Map<'tcx>) -> Self {
         let param_env = tcx.param_env_reveal_all_normalized(body.source.def_id());
         Self {
             map,
@@ -560,12 +560,13 @@ impl<'tcx, 'locals> Collector<'tcx, 'locals> {
         Self { patch: Patch::new(tcx), local_decls }
     }
 
+    #[instrument(level = "trace", skip(self, ecx, map), ret)]
     fn try_make_constant(
         &self,
         ecx: &mut InterpCx<'tcx, DummyMachine>,
         place: Place<'tcx>,
         state: &State<FlatSet<Scalar>>,
-        map: &Map,
+        map: &Map<'tcx>,
     ) -> Option<Const<'tcx>> {
         let ty = place.ty(self.local_decls, self.patch.tcx).ty;
         let layout = ecx.layout_of(ty).ok()?;
@@ -598,10 +599,11 @@ impl<'tcx, 'locals> Collector<'tcx, 'locals> {
     }
 }
 
+#[instrument(level = "trace", skip(map), ret)]
 fn propagatable_scalar(
     place: PlaceIndex,
     state: &State<FlatSet<Scalar>>,
-    map: &Map,
+    map: &Map<'_>,
 ) -> Option<Scalar> {
     if let FlatSet::Elem(value) = state.get_idx(place, map)
         && value.try_to_scalar_int().is_ok()
@@ -613,14 +615,14 @@ fn propagatable_scalar(
     }
 }
 
-#[instrument(level = "trace", skip(ecx, state, map))]
+#[instrument(level = "trace", skip(ecx, state, map), ret)]
 fn try_write_constant<'tcx>(
     ecx: &mut InterpCx<'tcx, DummyMachine>,
     dest: &PlaceTy<'tcx>,
     place: PlaceIndex,
     ty: Ty<'tcx>,
     state: &State<FlatSet<Scalar>>,
-    map: &Map,
+    map: &Map<'tcx>,
 ) -> InterpResult<'tcx> {
     let layout = ecx.layout_of(ty)?;
 
@@ -719,6 +721,7 @@ impl<'mir, 'tcx>
 {
     type FlowState = State<FlatSet<Scalar>>;
 
+    #[instrument(level = "trace", skip(self, results, statement))]
     fn visit_statement_before_primary_effect(
         &mut self,
         results: &mut Results<'tcx, ValueAnalysisWrapper<ConstAnalysis<'_, 'tcx>>>,
@@ -740,6 +743,7 @@ impl<'mir, 'tcx>
         }
     }
 
+    #[instrument(level = "trace", skip(self, results, statement))]
     fn visit_statement_after_primary_effect(
         &mut self,
         results: &mut Results<'tcx, ValueAnalysisWrapper<ConstAnalysis<'_, 'tcx>>>,
@@ -834,7 +838,7 @@ struct OperandCollector<'tcx, 'map, 'locals, 'a> {
     state: &'a State<FlatSet<Scalar>>,
     visitor: &'a mut Collector<'tcx, 'locals>,
     ecx: &'map mut InterpCx<'tcx, DummyMachine>,
-    map: &'map Map,
+    map: &'map Map<'tcx>,
 }
 
 impl<'tcx> Visitor<'tcx> for OperandCollector<'tcx, '_, '_, '_> {
diff --git a/compiler/rustc_mir_transform/src/inline.rs b/compiler/rustc_mir_transform/src/inline.rs
index fe73715480f..fd9f0fec88d 100644
--- a/compiler/rustc_mir_transform/src/inline.rs
+++ b/compiler/rustc_mir_transform/src/inline.rs
@@ -41,6 +41,12 @@ struct CallSite<'tcx> {
 
 impl<'tcx> MirPass<'tcx> for Inline {
     fn is_enabled(&self, sess: &rustc_session::Session) -> bool {
+        // FIXME(#127234): Coverage instrumentation currently doesn't handle inlined
+        // MIR correctly when Modified Condition/Decision Coverage is enabled.
+        if sess.instrument_coverage_mcdc() {
+            return false;
+        }
+
         if let Some(enabled) = sess.opts.unstable_opts.inline_mir {
             return enabled;
         }
diff --git a/compiler/rustc_mir_transform/src/jump_threading.rs b/compiler/rustc_mir_transform/src/jump_threading.rs
index 97ec0cb39de..2100f4b4a1a 100644
--- a/compiler/rustc_mir_transform/src/jump_threading.rs
+++ b/compiler/rustc_mir_transform/src/jump_threading.rs
@@ -123,7 +123,7 @@ struct TOFinder<'tcx, 'a> {
     param_env: ty::ParamEnv<'tcx>,
     ecx: InterpCx<'tcx, DummyMachine>,
     body: &'a Body<'tcx>,
-    map: &'a Map,
+    map: &'a Map<'tcx>,
     loop_headers: &'a BitSet<BasicBlock>,
     /// We use an arena to avoid cloning the slices when cloning `state`.
     arena: &'a DroplessArena,