diff options
Diffstat (limited to 'compiler/rustc_interface/src')
| -rw-r--r-- | compiler/rustc_interface/src/passes.rs | 91 |
1 files changed, 0 insertions, 91 deletions
diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs index 241bc35857a..0b91c023cfc 100644 --- a/compiler/rustc_interface/src/passes.rs +++ b/compiler/rustc_interface/src/passes.rs @@ -26,7 +26,6 @@ use rustc_parse::{ }; use rustc_passes::{abi_test, input_stats, layout_test}; use rustc_resolve::Resolver; -use rustc_session::code_stats::VTableSizeInfo; use rustc_session::config::{CrateType, Input, OutFileName, OutputFilenames, OutputType}; use rustc_session::cstore::Untracked; use rustc_session::output::{collect_crate_types, filename_for_input, find_crate_name}; @@ -989,90 +988,6 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) { // we will fail to emit overlap diagnostics. Thus we invoke it here unconditionally. let _ = tcx.all_diagnostic_items(()); }); - - if sess.opts.unstable_opts.print_vtable_sizes { - let traits = tcx.traits(LOCAL_CRATE); - - for &tr in traits { - if !tcx.is_dyn_compatible(tr) { - continue; - } - - let name = ty::print::with_no_trimmed_paths!(tcx.def_path_str(tr)); - - let mut first_dsa = true; - - // Number of vtable entries, if we didn't have upcasting - let mut entries_ignoring_upcasting = 0; - // Number of vtable entries needed solely for upcasting - let mut entries_for_upcasting = 0; - - let trait_ref = ty::Binder::dummy(ty::TraitRef::identity(tcx, tr)); - - // A slightly edited version of the code in - // `rustc_trait_selection::traits::vtable::vtable_entries`, that works without self - // type and just counts number of entries. - // - // Note that this is technically wrong, for traits which have associated types in - // supertraits: - // - // trait A: AsRef<Self::T> + AsRef<()> { type T; } - // - // Without self type we can't normalize `Self::T`, so we can't know if `AsRef<Self::T>` - // and `AsRef<()>` are the same trait, thus we assume that those are different, and - // potentially over-estimate how many vtable entries there are. - // - // Similarly this is wrong for traits that have methods with possibly-impossible bounds. - // For example: - // - // trait B<T> { fn f(&self) where T: Copy; } - // - // Here `dyn B<u8>` will have 4 entries, while `dyn B<String>` will only have 3. - // However, since we don't know `T`, we can't know if `T: Copy` holds or not, - // thus we lean on the bigger side and say it has 4 entries. - traits::vtable::prepare_vtable_segments(tcx, trait_ref, |segment| { - match segment { - traits::vtable::VtblSegment::MetadataDSA => { - // If this is the first dsa, it would be included either way, - // otherwise it's needed for upcasting - if std::mem::take(&mut first_dsa) { - entries_ignoring_upcasting += 3; - } else { - entries_for_upcasting += 3; - } - } - - traits::vtable::VtblSegment::TraitOwnEntries { trait_ref, emit_vptr } => { - // Lookup the shape of vtable for the trait. - let own_existential_entries = - tcx.own_existential_vtable_entries(trait_ref.def_id()); - - // The original code here ignores the method if its predicates are - // impossible. We can't really do that as, for example, all not trivial - // bounds on generic parameters are impossible (since we don't know the - // parameters...), see the comment above. - entries_ignoring_upcasting += own_existential_entries.len(); - - if emit_vptr { - entries_for_upcasting += 1; - } - } - } - - std::ops::ControlFlow::Continue::<std::convert::Infallible>(()) - }); - - sess.code_stats.record_vtable_size(tr, &name, VTableSizeInfo { - trait_name: name.clone(), - entries: entries_ignoring_upcasting + entries_for_upcasting, - entries_ignoring_upcasting, - entries_for_upcasting, - upcasting_cost_percent: entries_for_upcasting as f64 - / entries_ignoring_upcasting as f64 - * 100., - }) - } - } } /// Check for the `#[rustc_error]` annotation, which forces an error in codegen. This is used @@ -1153,12 +1068,6 @@ pub(crate) fn start_codegen<'tcx>( tcx.sess.code_stats.print_type_sizes(); } - if tcx.sess.opts.unstable_opts.print_vtable_sizes { - let crate_name = tcx.crate_name(LOCAL_CRATE); - - tcx.sess.code_stats.print_vtable_sizes(crate_name); - } - codegen } |