Add perf triage for 2025-06-25 (#6760)

Signed-off-by: Ryan Levick <[email protected]>

Author: rylev

draft/2025-06-25-this-week-in-rust.md

@@ -120,7 +120,26 @@ If you are an event organizer hoping to expand the reach of your event, please s
 
 ### Rust Compiler Performance Triage
 
-<!-- Perf results go here -->
+A week dominated by the landing of a large patch implementing [RFC#3729](https://github.com/rust-lang/rfcs/pull/3729) which unfortunately introduced rather sizeable performance regressions (avg of ~1% instruction count on 111 primary benchmarks). This was deemed worth it so that the patch could land and performance could be won back in follow up PRs.
+
+Triage done by **@rylev**.
+Revision range: [45acf54e..42245d34](https://perf.rust-lang.org/?start=45acf54eea118ed27927282b5e0bfdcd80b7987c&end=42245d34d22ade32b3f276dcf74deb826841594c&absolute=false&stat=instructions%3Au)
+
+**Summary**:
+
+| (instructions:u)                   | mean  | range           | count |
+|:----------------------------------:|:-----:|:---------------:|:-----:|
+| Regressions ❌ <br /> (primary)    | 1.1%  | [0.2%, 9.1%]    | 123   |
+| Regressions ❌ <br /> (secondary)  | 1.0%  | [0.1%, 4.6%]    | 86    |
+| Improvements ✅ <br /> (primary)   | -3.8% | [-7.3%, -0.3%]  | 2     |
+| Improvements ✅ <br /> (secondary) | -2.3% | [-18.5%, -0.2%] | 44    |
+| All ❌✅ (primary)                 | 1.0%  | [-7.3%, 9.1%]   | 125   |
+
+
+2 Regressions, 4 Improvements, 10 Mixed; 7 of them in rollups
+40 artifact comparisons made in total
+
+[Full report here](https://github.com/rust-lang/rustc-perf/blob/a63db4d1799853b334e4106d914fba24e49c8782/triage/2025/2025-06-24.md)
 
 ### [Approved RFCs](https://github.com/rust-lang/rfcs/commits/master)