compiler/rustc_codegen_ssa/src/coverageinfo/ffi.rs

   1 use rustc_middle::mir::coverage::{CounterValueReference, MappedExpressionIndex};
   2
   3 /// Aligns with [llvm::coverage::Counter::CounterKind](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L91)
   4 #[derive(Copy, Clone, Debug)]
   5 #[repr(C)]
   6 pub enum CounterKind {
   7     Zero = 0,
   8     CounterValueReference = 1,
   9     Expression = 2,
  10 }
  11
  12 /// A reference to an instance of an abstract "counter" that will yield a value in a coverage
  13 /// report. Note that `id` has different interpretations, depending on the `kind`:
  14 ///   * For `CounterKind::Zero`, `id` is assumed to be `0`
  15 ///   * For `CounterKind::CounterValueReference`,  `id` matches the `counter_id` of the injected
  16 ///     instrumentation counter (the `index` argument to the LLVM intrinsic
  17 ///     `instrprof.increment()`)
  18 ///   * For `CounterKind::Expression`, `id` is the index into the coverage map's array of
  19 ///     counter expressions.
  20 /// Aligns with [llvm::coverage::Counter](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L98-L99)
  21 /// Important: The Rust struct layout (order and types of fields) must match its C++ counterpart.
  22 #[derive(Copy, Clone, Debug)]
  23 #[repr(C)]
  24 pub struct Counter {
  25     // Important: The layout (order and types of fields) must match its C++ counterpart.
  26     pub kind: CounterKind,
  27     pub id: u32,
  28 }
  29
  30 impl Counter {
  31     pub fn zero() -> Self {
  32         Self { kind: CounterKind::Zero, id: 0 }
  33     }
  34
  35     pub fn counter_value_reference(counter_id: CounterValueReference) -> Self {
  36         Self { kind: CounterKind::CounterValueReference, id: counter_id.into() }
  37     }
  38
  39     pub fn expression(mapped_expression_index: MappedExpressionIndex) -> Self {
  40         Self { kind: CounterKind::Expression, id: mapped_expression_index.into() }
  41     }
  42 }
  43
  44 /// Aligns with [llvm::coverage::CounterExpression::ExprKind](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L146)
  45 #[derive(Copy, Clone, Debug)]
  46 #[repr(C)]
  47 pub enum ExprKind {
  48     Subtract = 0,
  49     Add = 1,
  50 }
  51
  52 /// Aligns with [llvm::coverage::CounterExpression](https://github.com/rust-lang/llvm-project/blob/rustc/10.0-2020-05-05/llvm/include/llvm/ProfileData/Coverage/CoverageMapping.h#L147-L148)
  53 /// Important: The Rust struct layout (order and types of fields) must match its C++
  54 /// counterpart.
  55 #[derive(Copy, Clone, Debug)]
  56 #[repr(C)]
  57 pub struct CounterExpression {
  58     pub kind: ExprKind,
  59     pub lhs: Counter,
  60     pub rhs: Counter,
  61 }
  62
  63 impl CounterExpression {
  64     pub fn new(lhs: Counter, kind: ExprKind, rhs: Counter) -> Self {
  65         Self { kind, lhs, rhs }
  66     }
  67 }