From 67b85e2a1f4e7632e5805fcc6e6a6f53501dd357 Mon Sep 17 00:00:00 2001
From: Urgau <urgau@numericable.fr>
Date: Mon, 14 Oct 2024 16:37:54 +0200
Subject: [PATCH] Add fast-path when computing the default visibility

---
 compiler/rustc_monomorphize/src/partitioning.rs | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/compiler/rustc_monomorphize/src/partitioning.rs b/compiler/rustc_monomorphize/src/partitioning.rs
index 5bd484d7bb002..9bf7e67417eff 100644
--- a/compiler/rustc_monomorphize/src/partitioning.rs
+++ b/compiler/rustc_monomorphize/src/partitioning.rs
@@ -119,6 +119,7 @@ use rustc_middle::util::Providers;
 use rustc_session::CodegenUnits;
 use rustc_session::config::{DumpMonoStatsFormat, SwitchWithOptPath};
 use rustc_span::symbol::Symbol;
+use rustc_target::spec::SymbolVisibility;
 use tracing::debug;
 
 use crate::collector::{self, MonoItemCollectionStrategy, UsageMap};
@@ -904,6 +905,11 @@ fn mono_item_visibility<'tcx>(
 }
 
 fn default_visibility(tcx: TyCtxt<'_>, id: DefId, is_generic: bool) -> Visibility {
+    // Fast-path to avoid expensive query call below
+    if tcx.sess.default_visibility() == SymbolVisibility::Interposable {
+        return Visibility::Default;
+    }
+
     let export_level = if is_generic {
         // Generic functions never have export-level C.
         SymbolExportLevel::Rust
@@ -913,6 +919,7 @@ fn default_visibility(tcx: TyCtxt<'_>, id: DefId, is_generic: bool) -> Visibilit
             _ => SymbolExportLevel::Rust,
         }
     };
+
     match export_level {
         // C-export level items remain at `Default` to allow C code to
         // access and interpose them.