Auto merge of #77466 - Aaron1011:reland-drop-tree, r=matthewjasper

Re-land PR #71840 (Rework MIR drop tree lowering)

PR https://github.com/rust-lang/rust/pull/71840 was reverted in https://github.com/rust-lang/rust/pull/72989 to fix an LLVM error (https://github.com/rust-lang/rust/issues/72470). That LLVM error no longer occurs with the recent upgrade to LLVM 11 (https://github.com/rust-lang/rust/pull/73526), so let's try re-landing this PR.

I've cherry-picked the commits from the original PR (with the exception of the commit blessing test output), making as few modifications as possible. I addressed the rebase fallout in separate commits on top of those.

r? `@matthewjasper`

1 files changed, 8 insertions, 2 deletions

diff --git a/compiler/rustc_mir/src/util/graphviz.rs b/compiler/rustc_mir/src/util/graphviz.rs
index c10724ad404..857617e546e 100644
--- a/compiler/rustc_mir/src/util/graphviz.rs
+++ b/compiler/rustc_mir/src/util/graphviz.rs
@@ -111,13 +111,19 @@ where
     write!(w, r#"<table border="0" cellborder="1" cellspacing="0">"#)?;
 
     // Basic block number at the top.
+    let (blk, bgcolor) = if data.is_cleanup {
+        (format!("{} (cleanup)", block.index()), "lightblue")
+    } else {
+        let color = if dark_mode { "dimgray" } else { "gray" };
+        (format!("{}", block.index()), color)
+    };
     write!(
         w,
         r#"<tr><td bgcolor="{bgcolor}" {attrs} colspan="{colspan}">{blk}</td></tr>"#,
-        bgcolor = if dark_mode { "dimgray" } else { "gray" },
         attrs = r#"align="center""#,
         colspan = num_cols,
-        blk = block.index()
+        blk = blk,
+        bgcolor = bgcolor
     )?;
 
     init(w)?;