feat(divan_compat): add root frame and ipc with runner

Author: not-matthias

crates/divan_compat/divan_fork/src/bench/mod.rs

@@ -657,6 +657,7 @@ impl<'a> BenchContext<'a> {
 
         let bench_overheads = timer.bench_overheads();
 
+        let _guard = codspeed::fifo::BenchGuard::new_with_runner_fifo();
         while {
             // Conditions for when sampling is over:
             if elapsed_picos >= max_picos {
@@ -810,6 +811,7 @@ impl<'a> BenchContext<'a> {
                 elapsed_picos = elapsed_picos.saturating_add(progress_picos);
             }
         }
+        core::mem::drop(_guard);
 
         // Reset flag for ignoring allocations.
         crate::alloc::IGNORE_ALLOC.set(false);

crates/divan_compat/divan_fork/src/divan.rs

@@ -428,6 +428,13 @@ mod codspeed {
             bench_context.samples.time_samples.iter().map(|s| s.duration.picos / 1_000).collect();
         let max_time_ns = bench_context.options.max_time.map(|t| t.as_nanos());
 
+        if let Err(error) = ::codspeed::fifo::send_cmd(codspeed::fifo::Command::CurrentBenchmark {
+            pid: std::process::id(),
+            uri: uri.clone(),
+        }) {
+            eprintln!("Failed to send benchmark URI to runner: {}", error);
+        }
+
         ::codspeed::walltime::collect_raw_walltime_results(
             "divan",
             bench_name,

crates/divan_compat/divan_fork/src/thread_pool.rs

@@ -201,9 +201,17 @@ impl<F> TaskShared<F> {
         where
             F: Fn(usize),
         {
-            let task_fn = &(*task.cast::<TaskShared<F>>()).task_fn;
+            #[inline(never)]
+            unsafe fn __codspeed_root_frame__<F>(task: *const TaskShared<()>, thread: usize)
+            where
+                F: Fn(usize),
+            {
+                let task_fn = &(*task.cast::<TaskShared<F>>()).task_fn;
+
+                task_fn(thread);
+            }
 
-            task_fn(thread);
+            __codspeed_root_frame__::<F>(task, thread);
         }
 
         Self {