Rollup merge of rust-lang#110409 - Nilstrieb:some-manual-javascript-o…

…bject-notationing, r=fee1-dead

Don't use `serde_json` to serialize a simple JSON object

This avoids `rustc_data_structures` depending on `serde_json` which allows it to be compiled much earlier, unlocking most of rustc.

This used to not matter, but after rust-lang#110407 we're not blocked on fluent anymore, which means that it's now a blocking edge.
![image](https://user-images.githubusercontent.com/48135649/232313178-e0150420-3020-4eb6-98d3-fe5294a8f947.png)

This saves a few more seconds.

cc ``@Zoxc`` who added it recently

Cargo.lock

@@ -3189,7 +3189,6 @@ dependencies = [
  "rustc_index",
  "rustc_macros",
  "rustc_serialize",
- "serde_json",
  "smallvec",
  "stable_deref_trait",
  "stacker",

compiler/rustc_data_structures/Cargo.toml

@@ -21,7 +21,6 @@ rustc-hash = "1.1.0"
 rustc_index = { path = "../rustc_index", package = "rustc_index" }
 rustc_macros = { path = "../rustc_macros" }
 rustc_serialize = { path = "../rustc_serialize" }
-serde_json = "1.0.59"
 smallvec = { version = "1.8.1", features = [
  "const_generics",
  "union",

compiler/rustc_data_structures/src/profiling.rs

@@ -87,6 +87,7 @@ use crate::fx::FxHashMap;
 use std::borrow::Borrow;
 use std::collections::hash_map::Entry;
 use std::error::Error;
+use std::fmt::Display;
 use std::fs;
 use std::intrinsics::unlikely;
 use std::path::Path;
@@ -97,7 +98,6 @@ use std::time::{Duration, Instant};
 pub use measureme::EventId;
 use measureme::{EventIdBuilder, Profiler, SerializableString, StringId};
 use parking_lot::RwLock;
-use serde_json::json;
 use smallvec::SmallVec;
 
 bitflags::bitflags! {
@@ -763,6 +763,31 @@ impl Drop for VerboseTimingGuard<'_> {
  }
 }
 
+struct JsonTimePassesEntry<'a> {
+ pass: &'a str,
+ time: f64,
+ start_rss: Option<usize>,
+ end_rss: Option<usize>,
+}
+
+impl Display for JsonTimePassesEntry<'_> {
+ fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+ let Self { pass: what, time, start_rss, end_rss } = self;
+ write!(f, r#"{{"pass":"{what}","time":{time},"rss_start":"#).unwrap();
+ match start_rss {
+ Some(rss) => write!(f, "{rss}")?,
+ None => write!(f, "null")?,
+ }
+ write!(f, r#","rss_end":"#)?;
+ match end_rss {
+ Some(rss) => write!(f, "{rss}")?,
+ None => write!(f, "null")?,
+ }
+ write!(f, "}}")?;
+ Ok(())
+ }
+}
+
 pub fn print_time_passes_entry(
  what: &str,
  dur: Duration,
@@ -772,13 +797,10 @@ pub fn print_time_passes_entry(
 ) {
  match format {
  TimePassesFormat::Json => {
- let json = json!({
- "pass": what,
- "time": dur.as_secs_f64(),
- "rss_start": start_rss,
- "rss_end": end_rss,
- });
- eprintln!("time: {json}");
+ let entry =
+ JsonTimePassesEntry { pass: what, time: dur.as_secs_f64(), start_rss, end_rss };
+
+ eprintln!(r#"time: {entry}"#);
  return;
  }
  TimePassesFormat::Text => (),
@@ -894,3 +916,6 @@ cfg_if! {
  }
  }
 }
+
+#[cfg(test)]
+mod tests;

compiler/rustc_data_structures/src/profiling/tests.rs

@@ -0,0 +1,19 @@
+use super::JsonTimePassesEntry;
+
+#[test]
+fn with_rss() {
+ let entry =
+ JsonTimePassesEntry { pass: "typeck", time: 56.1, start_rss: Some(10), end_rss: Some(20) };
+
+ assert_eq!(entry.to_string(), r#"{"pass":"typeck","time":56.1,"rss_start":10,"rss_end":20}"#)
+}
+
+#[test]
+fn no_rss() {
+ let entry = JsonTimePassesEntry { pass: "typeck", time: 56.1, start_rss: None, end_rss: None };
+
+ assert_eq!(
+ entry.to_string(),
+ r#"{"pass":"typeck","time":56.1,"rss_start":null,"rss_end":null}"#
+ )
+}