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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 03:57:31 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-30 03:57:31 +0000
commitdc0db358abe19481e475e10c32149b53370f1a1c (patch)
treeab8ce99c4b255ce46f99ef402c27916055b899ee /compiler/rustc_codegen_ssa/src/coverageinfo
parentReleasing progress-linux version 1.71.1+dfsg1-2~progress7.99u1. (diff)
downloadrustc-dc0db358abe19481e475e10c32149b53370f1a1c.tar.xz
rustc-dc0db358abe19481e475e10c32149b53370f1a1c.zip
Merging upstream version 1.72.1+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'compiler/rustc_codegen_ssa/src/coverageinfo')
-rw-r--r--compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs89
-rw-r--r--compiler/rustc_codegen_ssa/src/coverageinfo/map.rs347
-rw-r--r--compiler/rustc_codegen_ssa/src/coverageinfo/mod.rs2
3 files changed, 0 insertions, 438 deletions
diff --git a/compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs b/compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs
deleted file mode 100644
index 1791ce4b3..000000000
--- a/compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs
+++ /dev/null
@@ -1,89 +0,0 @@
-use rustc_middle::mir::coverage::{CounterValueReference, MappedExpressionIndex};
-
-/// Must match the layout of `LLVMRustCounterKind`.
-#[derive(Copy, Clone, Debug)]
-#[repr(C)]
-pub enum CounterKind {
- Zero = 0,
- CounterValueReference = 1,
- Expression = 2,
-}
-
-/// A reference to an instance of an abstract "counter" that will yield a value in a coverage
-/// report. Note that `id` has different interpretations, depending on the `kind`:
-/// * For `CounterKind::Zero`, `id` is assumed to be `0`
-/// * For `CounterKind::CounterValueReference`, `id` matches the `counter_id` of the injected
-/// instrumentation counter (the `index` argument to the LLVM intrinsic
-/// `instrprof.increment()`)
-/// * For `CounterKind::Expression`, `id` is the index into the coverage map's array of
-/// counter expressions.
-///
-/// Corresponds to struct `llvm::coverage::Counter`.
-///
-/// Must match the layout of `LLVMRustCounter`.
-#[derive(Copy, Clone, Debug)]
-#[repr(C)]
-pub struct Counter {
- // Important: The layout (order and types of fields) must match its C++ counterpart.
- pub kind: CounterKind,
- id: u32,
-}
-
-impl Counter {
- /// Constructs a new `Counter` of kind `Zero`. For this `CounterKind`, the
- /// `id` is not used.
- pub fn zero() -> Self {
- Self { kind: CounterKind::Zero, id: 0 }
- }
-
- /// Constructs a new `Counter` of kind `CounterValueReference`, and converts
- /// the given 1-based counter_id to the required 0-based equivalent for
- /// the `Counter` encoding.
- pub fn counter_value_reference(counter_id: CounterValueReference) -> Self {
- Self { kind: CounterKind::CounterValueReference, id: counter_id.zero_based_index() }
- }
-
- /// Constructs a new `Counter` of kind `Expression`.
- pub fn expression(mapped_expression_index: MappedExpressionIndex) -> Self {
- Self { kind: CounterKind::Expression, id: mapped_expression_index.into() }
- }
-
- /// Returns true if the `Counter` kind is `Zero`.
- pub fn is_zero(&self) -> bool {
- matches!(self.kind, CounterKind::Zero)
- }
-
- /// An explicitly-named function to get the ID value, making it more obvious
- /// that the stored value is now 0-based.
- pub fn zero_based_id(&self) -> u32 {
- debug_assert!(!self.is_zero(), "`id` is undefined for CounterKind::Zero");
- self.id
- }
-}
-
-/// Corresponds to enum `llvm::coverage::CounterExpression::ExprKind`.
-///
-/// Must match the layout of `LLVMRustCounterExprKind`.
-#[derive(Copy, Clone, Debug)]
-#[repr(C)]
-pub enum ExprKind {
- Subtract = 0,
- Add = 1,
-}
-
-/// Corresponds to struct `llvm::coverage::CounterExpression`.
-///
-/// Must match the layout of `LLVMRustCounterExpression`.
-#[derive(Copy, Clone, Debug)]
-#[repr(C)]
-pub struct CounterExpression {
- pub kind: ExprKind,
- pub lhs: Counter,
- pub rhs: Counter,
-}
-
-impl CounterExpression {
- pub fn new(lhs: Counter, kind: ExprKind, rhs: Counter) -> Self {
- Self { kind, lhs, rhs }
- }
-}
diff --git a/compiler/rustc_codegen_ssa/src/coverageinfo/map.rs b/compiler/rustc_codegen_ssa/src/coverageinfo/map.rs
deleted file mode 100644
index e4da3b8de..000000000
--- a/compiler/rustc_codegen_ssa/src/coverageinfo/map.rs
+++ /dev/null
@@ -1,347 +0,0 @@
-pub use super::ffi::*;
-
-use rustc_index::{IndexSlice, IndexVec};
-use rustc_middle::mir::coverage::{
- CodeRegion, CounterValueReference, ExpressionOperandId, InjectedExpressionId,
- InjectedExpressionIndex, MappedExpressionIndex, Op,
-};
-use rustc_middle::ty::Instance;
-use rustc_middle::ty::TyCtxt;
-
-#[derive(Clone, Debug, PartialEq)]
-pub struct Expression {
- lhs: ExpressionOperandId,
- op: Op,
- rhs: ExpressionOperandId,
- region: Option<CodeRegion>,
-}
-
-/// Collects all of the coverage regions associated with (a) injected counters, (b) counter
-/// expressions (additions or subtraction), and (c) unreachable regions (always counted as zero),
-/// for a given Function. Counters and counter expressions have non-overlapping `id`s because they
-/// can both be operands in an expression. This struct also stores the `function_source_hash`,
-/// computed during instrumentation, and forwarded with counters.
-///
-/// Note, it may be important to understand LLVM's definitions of `unreachable` regions versus "gap
-/// regions" (or "gap areas"). A gap region is a code region within a counted region (either counter
-/// or expression), but the line or lines in the gap region are not executable (such as lines with
-/// only whitespace or comments). According to LLVM Code Coverage Mapping documentation, "A count
-/// for a gap area is only used as the line execution count if there are no other regions on a
-/// line."
-#[derive(Debug)]
-pub struct FunctionCoverage<'tcx> {
- instance: Instance<'tcx>,
- source_hash: u64,
- is_used: bool,
- counters: IndexVec<CounterValueReference, Option<CodeRegion>>,
- expressions: IndexVec<InjectedExpressionIndex, Option<Expression>>,
- unreachable_regions: Vec<CodeRegion>,
-}
-
-impl<'tcx> FunctionCoverage<'tcx> {
- /// Creates a new set of coverage data for a used (called) function.
- pub fn new(tcx: TyCtxt<'tcx>, instance: Instance<'tcx>) -> Self {
- Self::create(tcx, instance, true)
- }
-
- /// Creates a new set of coverage data for an unused (never called) function.
- pub fn unused(tcx: TyCtxt<'tcx>, instance: Instance<'tcx>) -> Self {
- Self::create(tcx, instance, false)
- }
-
- fn create(tcx: TyCtxt<'tcx>, instance: Instance<'tcx>, is_used: bool) -> Self {
- let coverageinfo = tcx.coverageinfo(instance.def);
- debug!(
- "FunctionCoverage::create(instance={:?}) has coverageinfo={:?}. is_used={}",
- instance, coverageinfo, is_used
- );
- Self {
- instance,
- source_hash: 0, // will be set with the first `add_counter()`
- is_used,
- counters: IndexVec::from_elem_n(None, coverageinfo.num_counters as usize),
- expressions: IndexVec::from_elem_n(None, coverageinfo.num_expressions as usize),
- unreachable_regions: Vec::new(),
- }
- }
-
- /// Returns true for a used (called) function, and false for an unused function.
- pub fn is_used(&self) -> bool {
- self.is_used
- }
-
- /// Sets the function source hash value. If called multiple times for the same function, all
- /// calls should have the same hash value.
- pub fn set_function_source_hash(&mut self, source_hash: u64) {
- if self.source_hash == 0 {
- self.source_hash = source_hash;
- } else {
- debug_assert_eq!(source_hash, self.source_hash);
- }
- }
-
- /// Adds a code region to be counted by an injected counter intrinsic.
- pub fn add_counter(&mut self, id: CounterValueReference, region: CodeRegion) {
- if let Some(previous_region) = self.counters[id].replace(region.clone()) {
- assert_eq!(previous_region, region, "add_counter: code region for id changed");
- }
- }
-
- /// Both counters and "counter expressions" (or simply, "expressions") can be operands in other
- /// expressions. Expression IDs start from `u32::MAX` and go down, so the range of expression
- /// IDs will not overlap with the range of counter IDs. Counters and expressions can be added in
- /// any order, and expressions can still be assigned contiguous (though descending) IDs, without
- /// knowing what the last counter ID will be.
- ///
- /// When storing the expression data in the `expressions` vector in the `FunctionCoverage`
- /// struct, its vector index is computed, from the given expression ID, by subtracting from
- /// `u32::MAX`.
- ///
- /// Since the expression operands (`lhs` and `rhs`) can reference either counters or
- /// expressions, an operand that references an expression also uses its original ID, descending
- /// from `u32::MAX`. Theses operands are translated only during code generation, after all
- /// counters and expressions have been added.
- pub fn add_counter_expression(
- &mut self,
- expression_id: InjectedExpressionId,
- lhs: ExpressionOperandId,
- op: Op,
- rhs: ExpressionOperandId,
- region: Option<CodeRegion>,
- ) {
- debug!(
- "add_counter_expression({:?}, lhs={:?}, op={:?}, rhs={:?} at {:?}",
- expression_id, lhs, op, rhs, region
- );
- let expression_index = self.expression_index(u32::from(expression_id));
- debug_assert!(
- expression_index.as_usize() < self.expressions.len(),
- "expression_index {} is out of range for expressions.len() = {}
- for {:?}",
- expression_index.as_usize(),
- self.expressions.len(),
- self,
- );
- if let Some(previous_expression) = self.expressions[expression_index].replace(Expression {
- lhs,
- op,
- rhs,
- region: region.clone(),
- }) {
- assert_eq!(
- previous_expression,
- Expression { lhs, op, rhs, region },
- "add_counter_expression: expression for id changed"
- );
- }
- }
-
- /// Add a region that will be marked as "unreachable", with a constant "zero counter".
- pub fn add_unreachable_region(&mut self, region: CodeRegion) {
- self.unreachable_regions.push(region)
- }
-
- /// Return the source hash, generated from the HIR node structure, and used to indicate whether
- /// or not the source code structure changed between different compilations.
- pub fn source_hash(&self) -> u64 {
- self.source_hash
- }
-
- /// Generate an array of CounterExpressions, and an iterator over all `Counter`s and their
- /// associated `Regions` (from which the LLVM-specific `CoverageMapGenerator` will create
- /// `CounterMappingRegion`s.
- pub fn get_expressions_and_counter_regions(
- &self,
- ) -> (Vec<CounterExpression>, impl Iterator<Item = (Counter, &CodeRegion)>) {
- assert!(
- self.source_hash != 0 || !self.is_used,
- "No counters provided the source_hash for used function: {:?}",
- self.instance
- );
-
- let counter_regions = self.counter_regions();
- let (counter_expressions, expression_regions) = self.expressions_with_regions();
- let unreachable_regions = self.unreachable_regions();
-
- let counter_regions =
- counter_regions.chain(expression_regions.into_iter().chain(unreachable_regions));
- (counter_expressions, counter_regions)
- }
-
- fn counter_regions(&self) -> impl Iterator<Item = (Counter, &CodeRegion)> {
- self.counters.iter_enumerated().filter_map(|(index, entry)| {
- // Option::map() will return None to filter out missing counters. This may happen
- // if, for example, a MIR-instrumented counter is removed during an optimization.
- entry.as_ref().map(|region| (Counter::counter_value_reference(index), region))
- })
- }
-
- fn expressions_with_regions(
- &self,
- ) -> (Vec<CounterExpression>, impl Iterator<Item = (Counter, &CodeRegion)>) {
- let mut counter_expressions = Vec::with_capacity(self.expressions.len());
- let mut expression_regions = Vec::with_capacity(self.expressions.len());
- let mut new_indexes = IndexVec::from_elem_n(None, self.expressions.len());
-
- // This closure converts any `Expression` operand (`lhs` or `rhs` of the `Op::Add` or
- // `Op::Subtract` operation) into its native `llvm::coverage::Counter::CounterKind` type
- // and value. Operand ID value `0` maps to `CounterKind::Zero`; values in the known range
- // of injected LLVM counters map to `CounterKind::CounterValueReference` (and the value
- // matches the injected counter index); and any other value is converted into a
- // `CounterKind::Expression` with the expression's `new_index`.
- //
- // Expressions will be returned from this function in a sequential vector (array) of
- // `CounterExpression`, so the expression IDs must be mapped from their original,
- // potentially sparse set of indexes, originally in reverse order from `u32::MAX`.
- //
- // An `Expression` as an operand will have already been encountered as an `Expression` with
- // operands, so its new_index will already have been generated (as a 1-up index value).
- // (If an `Expression` as an operand does not have a corresponding new_index, it was
- // probably optimized out, after the expression was injected into the MIR, so it will
- // get a `CounterKind::Zero` instead.)
- //
- // In other words, an `Expression`s at any given index can include other expressions as
- // operands, but expression operands can only come from the subset of expressions having
- // `expression_index`s lower than the referencing `Expression`. Therefore, it is
- // reasonable to look up the new index of an expression operand while the `new_indexes`
- // vector is only complete up to the current `ExpressionIndex`.
- let id_to_counter = |new_indexes: &IndexSlice<
- InjectedExpressionIndex,
- Option<MappedExpressionIndex>,
- >,
- id: ExpressionOperandId| {
- if id == ExpressionOperandId::ZERO {
- Some(Counter::zero())
- } else if id.index() < self.counters.len() {
- debug_assert!(
- id.index() > 0,
- "ExpressionOperandId indexes for counters are 1-based, but this id={}",
- id.index()
- );
- // Note: Some codegen-injected Counters may be only referenced by `Expression`s,
- // and may not have their own `CodeRegion`s,
- let index = CounterValueReference::from(id.index());
- // Note, the conversion to LLVM `Counter` adjusts the index to be zero-based.
- Some(Counter::counter_value_reference(index))
- } else {
- let index = self.expression_index(u32::from(id));
- self.expressions
- .get(index)
- .expect("expression id is out of range")
- .as_ref()
- // If an expression was optimized out, assume it would have produced a count
- // of zero. This ensures that expressions dependent on optimized-out
- // expressions are still valid.
- .map_or(Some(Counter::zero()), |_| new_indexes[index].map(Counter::expression))
- }
- };
-
- for (original_index, expression) in
- self.expressions.iter_enumerated().filter_map(|(original_index, entry)| {
- // Option::map() will return None to filter out missing expressions. This may happen
- // if, for example, a MIR-instrumented expression is removed during an optimization.
- entry.as_ref().map(|expression| (original_index, expression))
- })
- {
- let optional_region = &expression.region;
- let Expression { lhs, op, rhs, .. } = *expression;
-
- if let Some(Some((lhs_counter, mut rhs_counter))) = id_to_counter(&new_indexes, lhs)
- .map(|lhs_counter| {
- id_to_counter(&new_indexes, rhs).map(|rhs_counter| (lhs_counter, rhs_counter))
- })
- {
- if lhs_counter.is_zero() && op.is_subtract() {
- // The left side of a subtraction was probably optimized out. As an example,
- // a branch condition might be evaluated as a constant expression, and the
- // branch could be removed, dropping unused counters in the process.
- //
- // Since counters are unsigned, we must assume the result of the expression
- // can be no more and no less than zero. An expression known to evaluate to zero
- // does not need to be added to the coverage map.
- //
- // Coverage test `loops_branches.rs` includes multiple variations of branches
- // based on constant conditional (literal `true` or `false`), and demonstrates
- // that the expected counts are still correct.
- debug!(
- "Expression subtracts from zero (assume unreachable): \
- original_index={:?}, lhs={:?}, op={:?}, rhs={:?}, region={:?}",
- original_index, lhs, op, rhs, optional_region,
- );
- rhs_counter = Counter::zero();
- }
- debug_assert!(
- lhs_counter.is_zero()
- // Note: with `as usize` the ID _could_ overflow/wrap if `usize = u16`
- || ((lhs_counter.zero_based_id() as usize)
- <= usize::max(self.counters.len(), self.expressions.len())),
- "lhs id={} > both counters.len()={} and expressions.len()={}
- ({:?} {:?} {:?})",
- lhs_counter.zero_based_id(),
- self.counters.len(),
- self.expressions.len(),
- lhs_counter,
- op,
- rhs_counter,
- );
-
- debug_assert!(
- rhs_counter.is_zero()
- // Note: with `as usize` the ID _could_ overflow/wrap if `usize = u16`
- || ((rhs_counter.zero_based_id() as usize)
- <= usize::max(self.counters.len(), self.expressions.len())),
- "rhs id={} > both counters.len()={} and expressions.len()={}
- ({:?} {:?} {:?})",
- rhs_counter.zero_based_id(),
- self.counters.len(),
- self.expressions.len(),
- lhs_counter,
- op,
- rhs_counter,
- );
-
- // Both operands exist. `Expression` operands exist in `self.expressions` and have
- // been assigned a `new_index`.
- let mapped_expression_index =
- MappedExpressionIndex::from(counter_expressions.len());
- let expression = CounterExpression::new(
- lhs_counter,
- match op {
- Op::Add => ExprKind::Add,
- Op::Subtract => ExprKind::Subtract,
- },
- rhs_counter,
- );
- debug!(
- "Adding expression {:?} = {:?}, region: {:?}",
- mapped_expression_index, expression, optional_region
- );
- counter_expressions.push(expression);
- new_indexes[original_index] = Some(mapped_expression_index);
- if let Some(region) = optional_region {
- expression_regions.push((Counter::expression(mapped_expression_index), region));
- }
- } else {
- bug!(
- "expression has one or more missing operands \
- original_index={:?}, lhs={:?}, op={:?}, rhs={:?}, region={:?}",
- original_index,
- lhs,
- op,
- rhs,
- optional_region,
- );
- }
- }
- (counter_expressions, expression_regions.into_iter())
- }
-
- fn unreachable_regions(&self) -> impl Iterator<Item = (Counter, &CodeRegion)> {
- self.unreachable_regions.iter().map(|region| (Counter::zero(), region))
- }
-
- fn expression_index(&self, id_descending_from_max: u32) -> InjectedExpressionIndex {
- debug_assert!(id_descending_from_max >= self.counters.len() as u32);
- InjectedExpressionIndex::from(u32::MAX - id_descending_from_max)
- }
-}
diff --git a/compiler/rustc_codegen_ssa/src/coverageinfo/mod.rs b/compiler/rustc_codegen_ssa/src/coverageinfo/mod.rs
deleted file mode 100644
index 569fd3f1a..000000000
--- a/compiler/rustc_codegen_ssa/src/coverageinfo/mod.rs
+++ /dev/null
@@ -1,2 +0,0 @@
-pub mod ffi;
-pub mod map;