1use std::fs::OpenOptions;
2use std::io::prelude::*;
3
4use rustc_middle::ty::{self, ClosureSizeProfileData, Instance, TyCtxt};
5
6/// For a given closure, writes out the data for the profiling the impact of RFC 2229 on
7/// closure size into a CSV.
8///
9/// During the same compile all closures dump the information in the same file
10/// "closure_profile_XXXXX.csv", which is created in the directory where the compiler is invoked.
11pub(crate) fn dump_closure_profile<'tcx>(tcx: TyCtxt<'tcx>, closure_instance: Instance<'tcx>) {
12 let Ok(mut file) = OpenOptions::new()
13 .create(true)
14 .append(true)
15 .open(&format!("closure_profile_{}.csv", std::process::id()))
16 else {
17 eprintln!("Couldn't open file for writing closure profile");
18 return;
19 };
20
21 let closure_def_id = closure_instance.def_id().expect_local();
22 let typeck_results = tcx.typeck(closure_def_id);
23
24 if typeck_results.closure_size_eval.contains_key(&closure_def_id) {
25 let typing_env = ty::TypingEnv::fully_monomorphized();
26
27 let ClosureSizeProfileData { before_feature_tys, after_feature_tys } =
28 typeck_results.closure_size_eval[&closure_def_id];
29
30 let before_feature_tys = tcx.instantiate_and_normalize_erasing_regions(
31 closure_instance.args,
32 typing_env,
33 ty::EarlyBinder::bind(before_feature_tys),
34 );
35 let after_feature_tys = tcx.instantiate_and_normalize_erasing_regions(
36 closure_instance.args,
37 typing_env,
38 ty::EarlyBinder::bind(after_feature_tys),
39 );
40
41 let new_size = tcx
42 .layout_of(typing_env.as_query_input(after_feature_tys))
43 .map(|l| format!("{:?}", l.size.bytes()))
44 .unwrap_or_else(|e| format!("Failed {e:?}"));
45
46 let old_size = tcx
47 .layout_of(typing_env.as_query_input(before_feature_tys))
48 .map(|l| format!("{:?}", l.size.bytes()))
49 .unwrap_or_else(|e| format!("Failed {e:?}"));
50
51 let closure_span = tcx.def_span(closure_def_id);
52 let src_file = tcx.sess.source_map().span_to_filename(closure_span);
53 let line_nos = tcx
54 .sess
55 .source_map()
56 .span_to_lines(closure_span)
57 .map(|l| format!("{:?} {:?}", l.lines.first(), l.lines.last()))
58 .unwrap_or_else(|e| format!("{e:?}"));
59
60 if let Err(e) = writeln!(
61 file,
62 "{}, {}, {}, {:?}",
63 old_size,
64 new_size,
65 src_file.prefer_local(),
66 line_nos
67 ) {
68 eprintln!("Error writing to file {e}")
69 }
70 }
71}
72