compiler/rustc_span/src/profiling.rs

   1 use std::borrow::Borrow;
   2
   3 use rustc_data_structures::profiling::EventArgRecorder;
   4
   5 /// Extension trait for self-profiling purposes: allows to record spans within a generic activity's
   6 /// event arguments.
   7 pub trait SpannedEventArgRecorder {
   8     /// Records the following event arguments within the current generic activity being profiled:
   9     /// - the provided `event_arg`
  10     /// - a string representation of the provided `span`
  11     ///
  12     /// Note: when self-profiling with costly event arguments, at least one argument
  13     /// needs to be recorded. A panic will be triggered if that doesn't happen.
  14     fn record_arg_with_span<A>(&mut self, event_arg: A, span: crate::Span)
  15     where
  16         A: Borrow<str> + Into<String>;
  17 }
  18
  19 impl SpannedEventArgRecorder for EventArgRecorder<'_> {
  20     fn record_arg_with_span<A>(&mut self, event_arg: A, span: crate::Span)
  21     where
  22         A: Borrow<str> + Into<String>,
  23     {
  24         self.record_arg(event_arg);
  25
  26         let span_arg = crate::with_session_globals(|session_globals| {
  27             if let Some(source_map) = &*session_globals.source_map.borrow() {
  28                 source_map.span_to_embeddable_string(span)
  29             } else {
  30                 format!("{span:?}")
  31             }
  32         });
  33         self.record_arg(span_arg);
  34     }
  35 }