From 215b377cc327dbd1140fbc0168b69fa8ae345c6d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?R=C3=A9my=20Rakic?= Date: Fri, 1 Apr 2022 20:59:23 +0200 Subject: [PATCH 1/2] extend `EventArgRecorder` into span-aware `SpannedEventArgRecorder` The self-profiler's `EventArgRecorder` is general-purpose in its ability to record Strings (and `rustc_span` depends on the crate its defined in, `rustc_data_structure`). Some generic activities could use recording locations where they happen in the user's code: to allow e.g. to track macro expansions and diagnose performance issues there. This adds a `SpannedEventArgRecorder` that can record an argument given as a span, rather than a String, since turning spans into Strings can be tricky if you're not happy with its default Debug output. This way the recorder can have a `record_arg_spanned` method which will do that. --- compiler/rustc_span/src/lib.rs | 2 ++ compiler/rustc_span/src/profiling.rs | 35 ++++++++++++++++++++++++++++ 2 files changed, 37 insertions(+) create mode 100644 compiler/rustc_span/src/profiling.rs diff --git a/compiler/rustc_span/src/lib.rs b/compiler/rustc_span/src/lib.rs index b0307cc20d174..f22faef2580a5 100644 --- a/compiler/rustc_span/src/lib.rs +++ b/compiler/rustc_span/src/lib.rs @@ -59,6 +59,8 @@ pub use symbol::{sym, Symbol}; mod analyze_source_file; pub mod fatal_error; +pub mod profiling; + use rustc_data_structures::stable_hasher::{HashStable, StableHasher}; use rustc_data_structures::sync::{Lock, Lrc}; diff --git a/compiler/rustc_span/src/profiling.rs b/compiler/rustc_span/src/profiling.rs new file mode 100644 index 0000000000000..f169007fab43d --- /dev/null +++ b/compiler/rustc_span/src/profiling.rs @@ -0,0 +1,35 @@ +use std::borrow::Borrow; + +use rustc_data_structures::profiling::EventArgRecorder; + +/// Extension trait for self-profiling purposes: allows to record spans within a generic activity's +/// event arguments. +pub trait SpannedEventArgRecorder { + /// Records the following event arguments within the current generic activity being profiled: + /// - the provided `event_arg` + /// - a string representation of the provided `span` + /// + /// Note: when self-profiling with costly event arguments, at least one argument + /// needs to be recorded. A panic will be triggered if that doesn't happen. + fn record_arg_with_span(&mut self, event_arg: A, span: crate::Span) + where + A: Borrow + Into; +} + +impl SpannedEventArgRecorder for EventArgRecorder<'_> { + fn record_arg_with_span(&mut self, event_arg: A, span: crate::Span) + where + A: Borrow + Into, + { + self.record_arg(event_arg); + + let span_arg = crate::with_session_globals(|session_globals| { + if let Some(source_map) = &*session_globals.source_map.borrow() { + source_map.span_to_embeddable_string(span) + } else { + format!("{:?}", span) + } + }); + self.record_arg(span_arg); + } +} From c52539605818d5c00870e1e973e99e8220c4a888 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?R=C3=A9my=20Rakic?= Date: Fri, 1 Apr 2022 21:00:51 +0200 Subject: [PATCH 2/2] start tracking proc-macros expansion spans in the self-profiler --- compiler/rustc_expand/src/proc_macro.rs | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/compiler/rustc_expand/src/proc_macro.rs b/compiler/rustc_expand/src/proc_macro.rs index aec401a041ca3..8e1966a0711d6 100644 --- a/compiler/rustc_expand/src/proc_macro.rs +++ b/compiler/rustc_expand/src/proc_macro.rs @@ -9,6 +9,7 @@ use rustc_data_structures::sync::Lrc; use rustc_errors::ErrorGuaranteed; use rustc_parse::nt_to_tokenstream; use rustc_parse::parser::ForceCollect; +use rustc_span::profiling::SpannedEventArgRecorder; use rustc_span::{Span, DUMMY_SP}; const EXEC_STRATEGY: pm::bridge::server::SameThread = pm::bridge::server::SameThread; @@ -25,7 +26,10 @@ impl base::ProcMacro for BangProcMacro { input: TokenStream, ) -> Result { let _timer = - ecx.sess.prof.generic_activity_with_arg("expand_proc_macro", ecx.expansion_descr()); + ecx.sess.prof.generic_activity_with_arg_recorder("expand_proc_macro", |recorder| { + recorder.record_arg_with_span(ecx.expansion_descr(), span); + }); + let proc_macro_backtrace = ecx.ecfg.proc_macro_backtrace; let server = proc_macro_server::Rustc::new(ecx); self.client.run(&EXEC_STRATEGY, server, input, proc_macro_backtrace).map_err(|e| { @@ -51,7 +55,10 @@ impl base::AttrProcMacro for AttrProcMacro { annotated: TokenStream, ) -> Result { let _timer = - ecx.sess.prof.generic_activity_with_arg("expand_proc_macro", ecx.expansion_descr()); + ecx.sess.prof.generic_activity_with_arg_recorder("expand_proc_macro", |recorder| { + recorder.record_arg_with_span(ecx.expansion_descr(), span); + }); + let proc_macro_backtrace = ecx.ecfg.proc_macro_backtrace; let server = proc_macro_server::Rustc::new(ecx); self.client @@ -103,7 +110,9 @@ impl MultiItemModifier for ProcMacroDerive { let stream = { let _timer = - ecx.sess.prof.generic_activity_with_arg("expand_proc_macro", ecx.expansion_descr()); + ecx.sess.prof.generic_activity_with_arg_recorder("expand_proc_macro", |recorder| { + recorder.record_arg_with_span(ecx.expansion_descr(), span); + }); let proc_macro_backtrace = ecx.ecfg.proc_macro_backtrace; let server = proc_macro_server::Rustc::new(ecx); match self.client.run(&EXEC_STRATEGY, server, input, proc_macro_backtrace) {