Rollup merge of #129686 - Zalathar:source-region, r=compiler-errors

coverage: Rename `CodeRegion` to `SourceRegion`

LLVM uses the word "code" to refer to a particular kind of coverage mapping. This unrelated usage of the word is confusing, and makes it harder to introduce types whose names correspond to the LLVM classification of coverage kinds.

No functional changes.

compiler/rustc_codegen_llvm/src/coverageinfo/ffi.rs

@@ -1,5 +1,5 @@
 use rustc_middle::mir::coverage::{
-    CodeRegion, ConditionInfo, CounterId, CovTerm, DecisionInfo, ExpressionId, MappingKind,
+    ConditionInfo, CounterId, CovTerm, DecisionInfo, ExpressionId, MappingKind, SourceRegion,
 };
 
 /// Must match the layout of `LLVMRustCounterKind`.
@@ -236,9 +236,10 @@ impl CounterMappingRegion {
     pub(crate) fn from_mapping(
         mapping_kind: &MappingKind,
         local_file_id: u32,
-        code_region: &CodeRegion,
+        source_region: &SourceRegion,
     ) -> Self {
-        let &CodeRegion { file_name: _, start_line, start_col, end_line, end_col } = code_region;
+        let &SourceRegion { file_name: _, start_line, start_col, end_line, end_col } =
+            source_region;
         match *mapping_kind {
             MappingKind::Code(term) => Self::code_region(
                 Counter::from_term(term),

compiler/rustc_codegen_llvm/src/coverageinfo/map_data.rs

@@ -2,8 +2,8 @@ use rustc_data_structures::captures::Captures;
 use rustc_data_structures::fx::FxIndexSet;
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::coverage::{
-    CodeRegion, CounterId, CovTerm, Expression, ExpressionId, FunctionCoverageInfo, Mapping,
-    MappingKind, Op,
+    CounterId, CovTerm, Expression, ExpressionId, FunctionCoverageInfo, Mapping, MappingKind, Op,
+    SourceRegion,
 };
 use rustc_middle::ty::Instance;
 use rustc_span::Symbol;
@@ -201,7 +201,7 @@ impl<'tcx> FunctionCoverage<'tcx> {
 
     /// Returns an iterator over all filenames used by this function's mappings.
     pub(crate) fn all_file_names(&self) -> impl Iterator<Item = Symbol> + Captures<'_> {
-        self.function_coverage_info.mappings.iter().map(|mapping| mapping.code_region.file_name)
+        self.function_coverage_info.mappings.iter().map(|mapping| mapping.source_region.file_name)
     }
 
     /// Convert this function's coverage expression data into a form that can be
@@ -230,12 +230,12 @@ impl<'tcx> FunctionCoverage<'tcx> {
     /// that will be used by `mapgen` when preparing for FFI.
     pub(crate) fn counter_regions(
         &self,
-    ) -> impl Iterator<Item = (MappingKind, &CodeRegion)> + ExactSizeIterator {
+    ) -> impl Iterator<Item = (MappingKind, &SourceRegion)> + ExactSizeIterator {
         self.function_coverage_info.mappings.iter().map(move |mapping| {
-            let Mapping { kind, code_region } = mapping;
+            let Mapping { kind, source_region } = mapping;
             let kind =
                 kind.map_terms(|term| if self.is_zero_term(term) { CovTerm::Zero } else { term });
-            (kind, code_region)
+            (kind, source_region)
         })
     }
 

compiler/rustc_middle/src/arena.rs

@@ -35,7 +35,6 @@ macro_rules! arena_types {
             )>,
             [] crate_for_resolver: rustc_data_structures::steal::Steal<(rustc_ast::Crate, rustc_ast::AttrVec)>,
             [] resolutions: rustc_middle::ty::ResolverGlobalCtxt,
-            [decode] code_region: rustc_middle::mir::coverage::CodeRegion,
             [] const_allocs: rustc_middle::mir::interpret::Allocation,
             [] region_scope_tree: rustc_middle::middle::region::ScopeTree,
             // Required for the incremental on-disk cache

compiler/rustc_middle/src/mir/coverage.rs

@@ -163,15 +163,15 @@ impl Debug for CoverageKind {
 
 #[derive(Clone, TyEncodable, TyDecodable, Hash, HashStable, PartialEq, Eq, PartialOrd, Ord)]
 #[derive(TypeFoldable, TypeVisitable)]
-pub struct CodeRegion {
+pub struct SourceRegion {
     pub file_name: Symbol,
     pub start_line: u32,
     pub start_col: u32,
     pub end_line: u32,
     pub end_col: u32,
 }
 
-impl Debug for CodeRegion {
+impl Debug for SourceRegion {
     fn fmt(&self, fmt: &mut Formatter<'_>) -> fmt::Result {
         write!(
             fmt,
@@ -242,7 +242,7 @@ impl MappingKind {
 #[derive(TyEncodable, TyDecodable, Hash, HashStable, TypeFoldable, TypeVisitable)]
 pub struct Mapping {
     pub kind: MappingKind,
-    pub code_region: CodeRegion,
+    pub source_region: SourceRegion,
 }
 
 /// Stores per-function coverage information attached to a `mir::Body`,

compiler/rustc_middle/src/mir/pretty.rs

@@ -547,8 +547,8 @@ fn write_function_coverage_info(
     for (id, expression) in expressions.iter_enumerated() {
         writeln!(w, "{INDENT}coverage {id:?} => {expression:?};")?;
     }
-    for coverage::Mapping { kind, code_region } in mappings {
-        writeln!(w, "{INDENT}coverage {kind:?} => {code_region:?};")?;
+    for coverage::Mapping { kind, source_region } in mappings {
+        writeln!(w, "{INDENT}coverage {kind:?} => {source_region:?};")?;
     }
     writeln!(w)?;
 

compiler/rustc_middle/src/ty/codec.rs

@@ -462,7 +462,6 @@ impl_decodable_via_ref! {
     &'tcx traits::ImplSource<'tcx, ()>,
     &'tcx mir::Body<'tcx>,
     &'tcx mir::BorrowCheckResult<'tcx>,
-    &'tcx mir::coverage::CodeRegion,
     &'tcx ty::List<ty::BoundVariableKind>,
     &'tcx ty::ListWithCachedTypeInfo<ty::Clause<'tcx>>,
     &'tcx ty::List<FieldIdx>,

compiler/rustc_mir_transform/src/coverage/mod.rs

@@ -13,7 +13,7 @@ use rustc_hir::intravisit::{walk_expr, Visitor};
 use rustc_middle::hir::map::Map;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::mir::coverage::{
-    CodeRegion, CoverageKind, DecisionInfo, FunctionCoverageInfo, Mapping, MappingKind,
+    CoverageKind, DecisionInfo, FunctionCoverageInfo, Mapping, MappingKind, SourceRegion,
 };
 use rustc_middle::mir::{
     self, BasicBlock, BasicBlockData, SourceInfo, Statement, StatementKind, Terminator,
@@ -159,7 +159,7 @@ fn create_mappings<'tcx>(
             .expect("all BCBs with spans were given counters")
             .as_term()
     };
-    let region_for_span = |span: Span| make_code_region(source_map, file_name, span, body_span);
+    let region_for_span = |span: Span| make_source_region(source_map, file_name, span, body_span);
 
     // Fully destructure the mappings struct to make sure we don't miss any kinds.
     let ExtractedMappings {
@@ -175,9 +175,9 @@ fn create_mappings<'tcx>(
     mappings.extend(code_mappings.iter().filter_map(
         // Ordinary code mappings are the simplest kind.
         |&mappings::CodeMapping { span, bcb }| {
-            let code_region = region_for_span(span)?;
+            let source_region = region_for_span(span)?;
             let kind = MappingKind::Code(term_for_bcb(bcb));
-            Some(Mapping { kind, code_region })
+            Some(Mapping { kind, source_region })
         },
     ));
 
@@ -186,29 +186,29 @@ fn create_mappings<'tcx>(
             let true_term = term_for_bcb(true_bcb);
             let false_term = term_for_bcb(false_bcb);
             let kind = MappingKind::Branch { true_term, false_term };
-            let code_region = region_for_span(span)?;
-            Some(Mapping { kind, code_region })
+            let source_region = region_for_span(span)?;
+            Some(Mapping { kind, source_region })
         },
     ));
 
     mappings.extend(mcdc_branches.iter().filter_map(
         |&mappings::MCDCBranch { span, true_bcb, false_bcb, condition_info, decision_depth: _ }| {
-            let code_region = region_for_span(span)?;
+            let source_region = region_for_span(span)?;
             let true_term = term_for_bcb(true_bcb);
             let false_term = term_for_bcb(false_bcb);
             let kind = match condition_info {
                 Some(mcdc_params) => MappingKind::MCDCBranch { true_term, false_term, mcdc_params },
                 None => MappingKind::Branch { true_term, false_term },
             };
-            Some(Mapping { kind, code_region })
+            Some(Mapping { kind, source_region })
         },
     ));
 
     mappings.extend(mcdc_decisions.iter().filter_map(
         |&mappings::MCDCDecision { span, bitmap_idx, num_conditions, .. }| {
-            let code_region = region_for_span(span)?;
+            let source_region = region_for_span(span)?;
             let kind = MappingKind::MCDCDecision(DecisionInfo { bitmap_idx, num_conditions });
-            Some(Mapping { kind, code_region })
+            Some(Mapping { kind, source_region })
         },
     ));
 
@@ -362,19 +362,13 @@ fn inject_statement(mir_body: &mut mir::Body<'_>, counter_kind: CoverageKind, bb
 /// but it's hard to rule out entirely (especially in the presence of complex macros
 /// or other expansions), and if it does happen then skipping a span or function is
 /// better than an ICE or `llvm-cov` failure that the user might have no way to avoid.
-fn make_code_region(
+#[instrument(level = "debug", skip(source_map))]
+fn make_source_region(
     source_map: &SourceMap,
     file_name: Symbol,
     span: Span,
     body_span: Span,
-) -> Option<CodeRegion> {
-    debug!(
-        "Called make_code_region(file_name={}, span={}, body_span={})",
-        file_name,
-        source_map.span_to_diagnostic_string(span),
-        source_map.span_to_diagnostic_string(body_span)
-    );
-
+) -> Option<SourceRegion> {
     let lo = span.lo();
     let hi = span.hi();
 
@@ -424,7 +418,7 @@ fn make_code_region(
     start_line = source_map.doctest_offset_line(&file.name, start_line);
     end_line = source_map.doctest_offset_line(&file.name, end_line);
 
-    check_code_region(CodeRegion {
+    check_source_region(SourceRegion {
         file_name,
         start_line: start_line as u32,
         start_col: start_col as u32,
@@ -433,12 +427,12 @@ fn make_code_region(
     })
 }
 
-/// If `llvm-cov` sees a code region that is improperly ordered (end < start),
+/// If `llvm-cov` sees a source region that is improperly ordered (end < start),
 /// it will immediately exit with a fatal error. To prevent that from happening,
 /// discard regions that are improperly ordered, or might be interpreted in a
 /// way that makes them improperly ordered.
-fn check_code_region(code_region: CodeRegion) -> Option<CodeRegion> {
-    let CodeRegion { file_name: _, start_line, start_col, end_line, end_col } = code_region;
+fn check_source_region(source_region: SourceRegion) -> Option<SourceRegion> {
+    let SourceRegion { file_name: _, start_line, start_col, end_line, end_col } = source_region;
 
     // Line/column coordinates are supposed to be 1-based. If we ever emit
     // coordinates of 0, `llvm-cov` might misinterpret them.
@@ -451,17 +445,17 @@ fn check_code_region(code_region: CodeRegion) -> Option<CodeRegion> {
     let is_ordered = (start_line, start_col) <= (end_line, end_col);
 
     if all_nonzero && end_col_has_high_bit_unset && is_ordered {
-        Some(code_region)
+        Some(source_region)
     } else {
         debug!(
-            ?code_region,
+            ?source_region,
             ?all_nonzero,
             ?end_col_has_high_bit_unset,
             ?is_ordered,
-            "Skipping code region that would be misinterpreted or rejected by LLVM"
+            "Skipping source region that would be misinterpreted or rejected by LLVM"
         );
         // If this happens in a debug build, ICE to make it easier to notice.
-        debug_assert!(false, "Improper code region: {code_region:?}");
+        debug_assert!(false, "Improper source region: {source_region:?}");
         None
     }
 }