Auto merge of #83152 - guswynn:jemallocator_part2, r=Mark-Simulacrum

Use tikv-jemallocator in rustc/rustdoc in addition to jemalloc-sys when enabled.

In https://github.com/rust-lang/rust/pull/81782 it was mentioned that one reason rustc may benefit from minimalloc is it doesn't use the `sdallocx` api from jemalloc.

Currently, on unix, rust uses jemalloc by importing its symbols to use them with the default, System (libc) global allocator.
This PR switches its global alloc to `tikv-jemallocator`, which correctly uses sized deallocation (https://docs.rs/tikv-jemallocator/0.4.1/src/tikv_jemallocator/lib.rs.html#121-126). `tikv-jemallocator`, as far as I can tell, is a more up-to-date set of bindings to jemalloc than `jemallocator`

The perf results of this pr are in large part due to the version upgrade of jemalloc, but sized deallocation has a non-trivial improvement, particularly to rustdoc.

This pr also includes changes to bootstrap to correctly pass the jemalloc feature through to the rustdoc build

1 files changed, 6 insertions, 1 deletions

diff --git a/src/bootstrap/tool.rs b/src/bootstrap/tool.rs
index f9be35d7c5e..e85f4628fb0 100644
--- a/src/bootstrap/tool.rs
+++ b/src/bootstrap/tool.rs
@@ -532,6 +532,11 @@ impl Step for Rustdoc {
         // they'll be linked to those libraries). As such, don't explicitly `ensure` any additional
         // libraries here. The intuition here is that If we've built a compiler, we should be able
         // to build rustdoc.
+        //
+        let mut features = Vec::new();
+        if builder.config.jemalloc {
+            features.push("jemalloc".to_string());
+        }
 
         let cargo = prepare_tool_cargo(
             builder,
@@ -541,7 +546,7 @@ impl Step for Rustdoc {
             "build",
             "src/tools/rustdoc",
             SourceType::InTree,
-            &[],
+            features.as_slice(),
         );
 
         builder.info(&format!(