adding Profiler

Author: jasonwilliams

.gitignore

@@ -17,3 +17,9 @@ yarn-error.log
 
 # tests/js/test.js is used for testing changes locally
 tests/js/test.js
+
+# Profiling
+*.string_data
+*.string_index
+*.events
+chrome_profiler.json

Cargo.lock

@@ -20,6 +20,7 @@ rustc-hash = "1.1.0"
 
 # Optional Dependencies
 serde = { version = "1.0.106", features = ["derive"], optional = true }
+measureme = { version = "0.7.1" }
 
 [dev-dependencies]
 criterion = "0.3.2"

boa/Cargo.toml

@@ -36,11 +36,13 @@
 pub mod builtins;
 pub mod environment;
 pub mod exec;
+pub mod profiler;
 pub mod realm;
 pub mod syntax;
 use crate::{
     builtins::value::ResultValue,
     exec::{Executor, Interpreter},
+    profiler::MyProfiler,
     realm::Realm,
     syntax::{ast::node::Node, lexer::Lexer, parser::Parser},
 };
@@ -76,6 +78,10 @@ pub fn forward(engine: &mut Interpreter, src: &str) -> String {
 /// Similar to `forward`, except the current value is returned instad of the string
 /// If the interpreter fails parsing an error value is returned instead (error object)
 pub fn forward_val(engine: &mut Interpreter, src: &str) -> ResultValue {
+    // Setup executor
+    let profiler = MyProfiler::new();
+    let _timer = profiler.start_event("Main");
+
     // Setup executor
     match parser_expr(src) {
         Ok(expr) => engine.run(&expr),

boa/src/lib.rs

@@ -0,0 +1,30 @@
+#![allow(missing_copy_implementations, missing_debug_implementations)]
+
+use measureme::{EventId, Profiler, TimingGuard};
+use std::{path::Path, thread::current};
+
+/// MmapSerializatioSink is faster on macOS and Linux
+/// but FileSerializationSink is faster on Windows
+#[cfg(not(windows))]
+type SerializationSink = measureme::MmapSerializationSink;
+#[cfg(windows)]
+type SerializationSink = measureme::FileSerializationSink;
+
+pub struct MyProfiler {
+    profiler: Profiler<SerializationSink>,
+}
+
+impl MyProfiler {
+    pub fn start_event(&self, label: &str) -> TimingGuard<'_, SerializationSink> {
+        let kind = self.profiler.alloc_string("Generic");
+        let id = EventId::from_label(self.profiler.alloc_string(label));
+        let thread_id = current().id().as_u64() as u32;
+        self.profiler
+            .start_recording_interval_event(kind, id, thread_id)
+    }
+
+    pub fn new() -> MyProfiler {
+        let profiler = Profiler::new(Path::new("./my_trace")).unwrap();
+        MyProfiler { profiler }
+    }
+}