diff --git a/src/tools/compiletest/src/header.rs b/src/tools/compiletest/src/header.rs
index ad10c3e07cef4..994156bdfd7b1 100644
--- a/src/tools/compiletest/src/header.rs
+++ b/src/tools/compiletest/src/header.rs
@@ -541,16 +541,15 @@ impl TestProps {
     }
 
     fn update_pass_mode(&mut self, ln: &str, revision: Option<&str>, config: &Config) {
-        let check_no_run = |s| {
-            if config.mode != Mode::Ui && config.mode != Mode::Incremental {
-                panic!("`{}` header is only supported in UI and incremental tests", s);
-            }
-            if config.mode == Mode::Incremental
-                && !revision.map_or(false, |r| r.starts_with("cfail"))
-                && !self.revisions.iter().all(|r| r.starts_with("cfail"))
-            {
-                panic!("`{}` header is only supported in `cfail` incremental tests", s);
+        let check_no_run = |s| match (config.mode, s) {
+            (Mode::Ui, _) => (),
+            (Mode::Codegen, "build-pass") => (),
+            (Mode::Incremental, _) => {
+                if revision.is_some() && !self.revisions.iter().all(|r| r.starts_with("cfail")) {
+                    panic!("`{s}` header is only supported in `cfail` incremental tests")
+                }
             }
+            (mode, _) => panic!("`{s}` header is not supported in `{mode}` tests"),
         };
         let pass_mode = if config.parse_name_directive(ln, "check-pass") {
             check_no_run("check-pass");
@@ -559,9 +558,7 @@ impl TestProps {
             check_no_run("build-pass");
             Some(PassMode::Build)
         } else if config.parse_name_directive(ln, "run-pass") {
-            if config.mode != Mode::Ui {
-                panic!("`run-pass` header is only supported in UI tests")
-            }
+            check_no_run("run-pass");
             Some(PassMode::Run)
         } else {
             None
diff --git a/src/tools/compiletest/src/runtest.rs b/src/tools/compiletest/src/runtest.rs
index ac19fe078f09e..b91e1b09330e1 100644
--- a/src/tools/compiletest/src/runtest.rs
+++ b/src/tools/compiletest/src/runtest.rs
@@ -2752,6 +2752,10 @@ impl<'test> TestCx<'test> {
             self.fatal_proc_rec("compilation failed!", &proc_res);
         }
 
+        if let Some(PassMode::Build) = self.pass_mode() {
+            return;
+        }
+
         let output_path = self.output_base_name().with_extension("ll");
         let proc_res = self.verify_with_filecheck(&output_path);
         if !proc_res.status.success() {
diff --git a/tests/codegen/simd-wide-sum.rs b/tests/codegen/simd-wide-sum.rs
index db2aa20bde7ab..3116f9597bcdb 100644
--- a/tests/codegen/simd-wide-sum.rs
+++ b/tests/codegen/simd-wide-sum.rs
@@ -1,6 +1,11 @@
+// revisions: llvm mir-opt3
 // compile-flags: -C opt-level=3 -Z merge-functions=disabled --edition=2021
 // only-x86_64
 // ignore-debug: the debug assertions get in the way
+// [mir-opt3]compile-flags: -Zmir-opt-level=3
+// [mir-opt3]build-pass
+
+// mir-opt3 is a regression test for https://github.com/rust-lang/rust/issues/98016
 
 #![crate_type = "lib"]
 #![feature(portable_simd)]
@@ -47,9 +52,8 @@ pub fn wider_reduce_iter(x: Simd<u8, N>) -> u16 {
 #[no_mangle]
 // CHECK-LABEL: @wider_reduce_into_iter
 pub fn wider_reduce_into_iter(x: Simd<u8, N>) -> u16 {
-    // FIXME MIR inlining messes up LLVM optimizations.
-    // WOULD-CHECK: zext <8 x i8>
-    // WOULD-CHECK-SAME: to <8 x i16>
-    // WOULD-CHECK: call i16 @llvm.vector.reduce.add.v8i16(<8 x i16>
+    // CHECK: zext <8 x i8>
+    // CHECK-SAME: to <8 x i16>
+    // CHECK: call i16 @llvm.vector.reduce.add.v8i16(<8 x i16>
     x.to_array().into_iter().map(u16::from).sum()
 }