mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Rollup merge of #95473 - lqd:macro-expansion, r=petrochenkov

Browse Source 
track individual proc-macro expansions in the self-profiler

As described in [this zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/131828-t-compiler/topic/Macro.20expansion.20performance.20on.20complex.20macros/near/275063190), users don't currently have a lot of information to diagnose macro expansion performance issues. That comment suggests using the macro names to add further timing information.

This PR starts to do this for proc-macros which have the same issue, and performance problems happening in the wild in [this other zulip thread](https://rust-lang.zulipchat.com/#narrow/stream/247081-t-compiler.2Fperformance/topic/Identifying.20proc-macro.20slowdowns) could be helped by such information.

It uses the available proc-macro name to track their individual expansions with self-profiling events.

r? `@Aaron1011` who mentioned this idea originally
This commit is contained in:
Dylan DPC 2022-04-05 22:58:55 +02:00 committed by GitHub
commit c5e7e95292
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
2 changed files with 24 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
compiler/rustc_expand/src/base.rs
View File

@ -1047,6 +1047,12 @@ impl<'a> ExtCtxt<'a> {
self.current_expansion.id.expn_data().call_site
}
/// Returns the current expansion kind's description.
pub(crate) fn expansion_descr(&self) -> String {
let expn_data = self.current_expansion.id.expn_data();
expn_data.kind.descr()
}
/// Equivalent of `Span::def_site` from the proc macro API,
/// except that the location is taken from the span passed as an argument.
pub fn with_def_site_ctxt(&self, span: Span) -> Span {

10
compiler/rustc_expand/src/proc_macro.rs
View File

@ -24,6 +24,8 @@ impl base::ProcMacro for BangProcMacro {
span: Span,
input: TokenStream,
) -> Result<TokenStream, ErrorGuaranteed> {
let _timer =
ecx.sess.prof.generic_activity_with_arg("expand_proc_macro", ecx.expansion_descr());
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| {
@ -48,6 +50,8 @@ impl base::AttrProcMacro for AttrProcMacro {
annotation: TokenStream,
annotated: TokenStream,
) -> Result<TokenStream, ErrorGuaranteed> {
let _timer =
ecx.sess.prof.generic_activity_with_arg("expand_proc_macro", ecx.expansion_descr());
let proc_macro_backtrace = ecx.ecfg.proc_macro_backtrace;
let server = proc_macro_server::Rustc::new(ecx);
self.client
@ -97,9 +101,12 @@ impl MultiItemModifier for ProcMacroDerive {
nt_to_tokenstream(&item, &ecx.sess.parse_sess, CanSynthesizeMissingTokens::No)
};
let stream = {
let _timer =
ecx.sess.prof.generic_activity_with_arg("expand_proc_macro", ecx.expansion_descr());
let proc_macro_backtrace = ecx.ecfg.proc_macro_backtrace;
let server = proc_macro_server::Rustc::new(ecx);
let stream = match self.client.run(&EXEC_STRATEGY, server, input, proc_macro_backtrace) {
match self.client.run(&EXEC_STRATEGY, server, input, proc_macro_backtrace) {
Ok(stream) => stream,
Err(e) => {
let mut err = ecx.struct_span_err(span, "proc-macro derive panicked");
@ -109,6 +116,7 @@ impl MultiItemModifier for ProcMacroDerive {
err.emit();
return ExpandResult::Ready(vec![]);
}
}
};
let error_count_before = ecx.sess.parse_sess.span_diagnostic.err_count();