Merge from rustc

3 files changed, 94 insertions, 13 deletions

diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index 99520a3fea3..02d1ebdb31a 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -8,9 +8,9 @@ use std::{env, fs, iter};
 use rustc_ast as ast;
 use rustc_codegen_ssa::traits::CodegenBackend;
 use rustc_data_structures::jobserver::Proxy;
-use rustc_data_structures::parallel;
 use rustc_data_structures::steal::Steal;
 use rustc_data_structures::sync::{AppendOnlyIndexVec, FreezeLock, WorkerLocal};
+use rustc_data_structures::{parallel, thousands};
 use rustc_expand::base::{ExtCtxt, LintStoreExpand};
 use rustc_feature::Features;
 use rustc_fs_util::try_canonicalize;
@@ -18,6 +18,7 @@ use rustc_hir::def_id::{LOCAL_CRATE, StableCrateId, StableCrateIdMap};
 use rustc_hir::definitions::Definitions;
 use rustc_incremental::setup_dep_graph;
 use rustc_lint::{BufferedEarlyLint, EarlyCheckNode, LintStore, unerased_lint_store};
+use rustc_metadata::EncodedMetadata;
 use rustc_metadata::creader::CStore;
 use rustc_middle::arena::Arena;
 use rustc_middle::dep_graph::DepsType;
@@ -35,7 +36,8 @@ use rustc_session::parse::feature_err;
 use rustc_session::search_paths::PathKind;
 use rustc_session::{Limit, Session};
 use rustc_span::{
-    DUMMY_SP, ErrorGuaranteed, FileName, SourceFileHash, SourceFileHashAlgorithm, Span, Symbol, sym,
+    DUMMY_SP, ErrorGuaranteed, ExpnKind, FileName, SourceFileHash, SourceFileHashAlgorithm, Span,
+    Symbol, sym,
 };
 use rustc_target::spec::PanicStrategy;
 use rustc_trait_selection::traits;
@@ -205,7 +207,7 @@ fn configure_and_expand(
         // Expand macros now!
         let krate = sess.time("expand_crate", || ecx.monotonic_expander().expand_crate(krate));
 
-        // The rest is error reporting
+        // The rest is error reporting and stats
 
         sess.psess.buffered_lints.with_lock(|buffered_lints: &mut Vec<BufferedEarlyLint>| {
             buffered_lints.append(&mut ecx.buffered_early_lint);
@@ -228,6 +230,10 @@ fn configure_and_expand(
             }
         }
 
+        if ecx.sess.opts.unstable_opts.macro_stats {
+            print_macro_stats(&ecx);
+        }
+
         krate
     });
 
@@ -288,6 +294,76 @@ fn configure_and_expand(
     krate
 }
 
+fn print_macro_stats(ecx: &ExtCtxt<'_>) {
+    use std::fmt::Write;
+
+    // No instability because we immediately sort the produced vector.
+    #[allow(rustc::potential_query_instability)]
+    let mut macro_stats: Vec<_> = ecx
+        .macro_stats
+        .iter()
+        .map(|((name, kind), stat)| {
+            // This gives the desired sort order: sort by bytes, then lines, etc.
+            (stat.bytes, stat.lines, stat.uses, name, *kind)
+        })
+        .collect();
+    macro_stats.sort_unstable();
+    macro_stats.reverse(); // bigger items first
+
+    let prefix = "macro-stats";
+    let name_w = 32;
+    let uses_w = 7;
+    let lines_w = 11;
+    let avg_lines_w = 11;
+    let bytes_w = 11;
+    let avg_bytes_w = 11;
+    let banner_w = name_w + uses_w + lines_w + avg_lines_w + bytes_w + avg_bytes_w;
+
+    // We write all the text into a string and print it with a single
+    // `eprint!`. This is an attempt to minimize interleaved text if multiple
+    // rustc processes are printing macro-stats at the same time (e.g. with
+    // `RUSTFLAGS='-Zmacro-stats' cargo build`). It still doesn't guarantee
+    // non-interleaving, though.
+    let mut s = String::new();
+    _ = writeln!(s, "{prefix} {}", "=".repeat(banner_w));
+    _ = writeln!(s, "{prefix} MACRO EXPANSION STATS: {}", ecx.ecfg.crate_name);
+    _ = writeln!(
+        s,
+        "{prefix} {:<name_w$}{:>uses_w$}{:>lines_w$}{:>avg_lines_w$}{:>bytes_w$}{:>avg_bytes_w$}",
+        "Macro Name", "Uses", "Lines", "Avg Lines", "Bytes", "Avg Bytes",
+    );
+    _ = writeln!(s, "{prefix} {}", "-".repeat(banner_w));
+    // It's helpful to print something when there are no entries, otherwise it
+    // might look like something went wrong.
+    if macro_stats.is_empty() {
+        _ = writeln!(s, "{prefix} (none)");
+    }
+    for (bytes, lines, uses, name, kind) in macro_stats {
+        let mut name = ExpnKind::Macro(kind, *name).descr();
+        let avg_lines = lines as f64 / uses as f64;
+        let avg_bytes = bytes as f64 / uses as f64;
+        if name.len() >= name_w {
+            // If the name is long, print it on a line by itself, then
+            // set the name to empty and print things normally, to show the
+            // stats on the next line.
+            _ = writeln!(s, "{prefix} {:<name_w$}", name);
+            name = String::new();
+        }
+        _ = writeln!(
+            s,
+            "{prefix} {:<name_w$}{:>uses_w$}{:>lines_w$}{:>avg_lines_w$}{:>bytes_w$}{:>avg_bytes_w$}",
+            name,
+            thousands::usize_with_underscores(uses),
+            thousands::isize_with_underscores(lines),
+            thousands::f64p1_with_underscores(avg_lines),
+            thousands::isize_with_underscores(bytes),
+            thousands::f64p1_with_underscores(avg_bytes),
+        );
+    }
+    _ = writeln!(s, "{prefix} {}", "=".repeat(banner_w));
+    eprint!("{s}");
+}
+
 fn early_lint_checks(tcx: TyCtxt<'_>, (): ()) {
     let sess = tcx.sess;
     let (resolver, krate) = &*tcx.resolver_for_lowering().borrow();
@@ -1099,7 +1175,7 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) {
 pub(crate) fn start_codegen<'tcx>(
     codegen_backend: &dyn CodegenBackend,
     tcx: TyCtxt<'tcx>,
-) -> Box<dyn Any> {
+) -> (Box<dyn Any>, EncodedMetadata) {
     // Hook for tests.
     if let Some((def_id, _)) = tcx.entry_fn(())
         && tcx.has_attr(def_id, sym::rustc_delayed_bug_from_inside_query)
@@ -1122,11 +1198,9 @@ pub(crate) fn start_codegen<'tcx>(
 
     info!("Pre-codegen\n{:?}", tcx.debug_stats());
 
-    let (metadata, need_metadata_module) = rustc_metadata::fs::encode_and_write_metadata(tcx);
+    let metadata = rustc_metadata::fs::encode_and_write_metadata(tcx);
 
-    let codegen = tcx.sess.time("codegen_crate", move || {
-        codegen_backend.codegen_crate(tcx, metadata, need_metadata_module)
-    });
+    let codegen = tcx.sess.time("codegen_crate", move || codegen_backend.codegen_crate(tcx));
 
     info!("Post-codegen\n{:?}", tcx.debug_stats());
 
@@ -1136,7 +1210,7 @@ pub(crate) fn start_codegen<'tcx>(
         tcx.sess.code_stats.print_type_sizes();
     }
 
-    codegen
+    (codegen, metadata)
 }
 
 /// Compute and validate the crate name.
diff --git a/compiler/rustc_interface/src/queries.rs b/compiler/rustc_interface/src/queries.rs
index c8914c9be9c..877440ec7d2 100644
--- a/compiler/rustc_interface/src/queries.rs
+++ b/compiler/rustc_interface/src/queries.rs
@@ -4,7 +4,9 @@ use std::sync::Arc;
 use rustc_codegen_ssa::CodegenResults;
 use rustc_codegen_ssa::traits::CodegenBackend;
 use rustc_data_structures::svh::Svh;
+use rustc_errors::timings::TimingSection;
 use rustc_hir::def_id::LOCAL_CRATE;
+use rustc_metadata::EncodedMetadata;
 use rustc_middle::dep_graph::DepGraph;
 use rustc_middle::ty::TyCtxt;
 use rustc_session::Session;
@@ -18,6 +20,7 @@ pub struct Linker {
     output_filenames: Arc<OutputFilenames>,
     // Only present when incr. comp. is enabled.
     crate_hash: Option<Svh>,
+    metadata: EncodedMetadata,
     ongoing_codegen: Box<dyn Any>,
 }
 
@@ -26,7 +29,7 @@ impl Linker {
         tcx: TyCtxt<'_>,
         codegen_backend: &dyn CodegenBackend,
     ) -> Linker {
-        let ongoing_codegen = passes::start_codegen(codegen_backend, tcx);
+        let (ongoing_codegen, metadata) = passes::start_codegen(codegen_backend, tcx);
 
         Linker {
             dep_graph: tcx.dep_graph.clone(),
@@ -36,6 +39,7 @@ impl Linker {
             } else {
                 None
             },
+            metadata,
             ongoing_codegen,
         }
     }
@@ -75,6 +79,7 @@ impl Linker {
                 sess,
                 &rlink_file,
                 &codegen_results,
+                &self.metadata,
                 &*self.output_filenames,
             )
             .unwrap_or_else(|error| {
@@ -84,6 +89,7 @@ impl Linker {
         }
 
         let _timer = sess.prof.verbose_generic_activity("link_crate");
-        codegen_backend.link(sess, codegen_results, &self.output_filenames)
+        let _timing = sess.timings.start_section(sess.dcx(), TimingSection::Linking);
+        codegen_backend.link(sess, codegen_results, self.metadata, &self.output_filenames)
     }
 }
diff --git a/compiler/rustc_interface/src/tests.rs b/compiler/rustc_interface/src/tests.rs
index 558f13a832c..a0012b04c4f 100644
--- a/compiler/rustc_interface/src/tests.rs
+++ b/compiler/rustc_interface/src/tests.rs
@@ -27,7 +27,7 @@ use rustc_span::source_map::{RealFileLoader, SourceMapInputs};
 use rustc_span::{FileName, SourceFileHashAlgorithm, sym};
 use rustc_target::spec::{
     CodeModel, FramePointer, LinkerFlavorCli, MergeFunctions, OnBrokenPipe, PanicStrategy,
-    RelocModel, RelroLevel, SanitizerSet, SplitDebuginfo, StackProtector, TlsModel, WasmCAbi,
+    RelocModel, RelroLevel, SanitizerSet, SplitDebuginfo, StackProtector, TlsModel,
 };
 
 use crate::interface::{initialize_checked_jobserver, parse_cfg};
@@ -709,6 +709,7 @@ fn test_unstable_options_tracking_hash() {
     untracked!(llvm_time_trace, true);
     untracked!(ls, vec!["all".to_owned()]);
     untracked!(macro_backtrace, true);
+    untracked!(macro_stats, true);
     untracked!(meta_stats, true);
     untracked!(mir_include_spans, MirIncludeSpans::On);
     untracked!(nll_facts, true);
@@ -801,6 +802,7 @@ fn test_unstable_options_tracking_hash() {
     tracked!(force_unstable_if_unmarked, true);
     tracked!(function_return, FunctionReturn::ThunkExtern);
     tracked!(function_sections, Some(false));
+    tracked!(hint_mostly_unused, true);
     tracked!(human_readable_cgu_names, true);
     tracked!(incremental_ignore_spans, true);
     tracked!(inline_mir, Some(true));
@@ -881,7 +883,6 @@ fn test_unstable_options_tracking_hash() {
     tracked!(verify_llvm_ir, true);
     tracked!(virtual_function_elimination, true);
     tracked!(wasi_exec_model, Some(WasiExecModel::Reactor));
-    tracked!(wasm_c_abi, WasmCAbi::Spec);
     // tidy-alphabetical-end
 
     macro_rules! tracked_no_crate_hash {