Auto merge of #98817 - the8472:dont-optimize-ui-tests, r=Mark-Simulacrum

Only obey optimize-tests flag on UI tests that are run-pass

stage1 UI tests walltime on my machine:

```
optimize-tests = false, master
25.98s

optimize-tests = true, master
34.69s

optimize-tests = true, patched
28.79s
```

Effects:

- faster UI tests
- llvm asserts get exercised less on build-pass tests
- the difference between opt and nopt builds shrinks a bit
- aux libs don't get optimized since they don't have a pass mode and almost never have explicit compile flags

1 files changed, 3 insertions, 6 deletions

diff --git a/src/bootstrap/test.rs b/src/bootstrap/test.rs
index 9958306b576..f3395507bb0 100644
--- a/src/bootstrap/test.rs
+++ b/src/bootstrap/test.rs
@@ -1363,13 +1363,10 @@ note: if you're sure you want to do this, please open an issue as to why. In the
         if let Some(ref npm) = builder.config.npm {
             cmd.arg("--npm").arg(npm);
         }
-
-        let mut flags = if is_rustdoc { Vec::new() } else { vec!["-Crpath".to_string()] };
-        if !is_rustdoc {
-            if builder.config.rust_optimize_tests {
-                flags.push("-O".to_string());
-            }
+        if builder.config.rust_optimize_tests {
+            cmd.arg("--optimize-tests");
         }
+        let mut flags = if is_rustdoc { Vec::new() } else { vec!["-Crpath".to_string()] };
         flags.push(format!("-Cdebuginfo={}", builder.config.rust_debuginfo_level_tests));
         flags.push(builder.config.cmd.rustc_args().join(" "));