diff --git a/src/tools/tidy/src/style.rs b/src/tools/tidy/src/style.rs
index 7bb424d926c26..aa0843e4d7771 100644
--- a/src/tools/tidy/src/style.rs
+++ b/src/tools/tidy/src/style.rs
@@ -445,6 +445,7 @@ pub fn check(path: &Path, tidy_ctx: TidyCtx) {
         let mut comment_block: Option<(usize, usize)> = None;
         let is_test = file.components().any(|c| c.as_os_str() == "tests")
             || file.file_stem().unwrap() == "tests";
+        let is_codegen_test = is_test && file.components().any(|c| c.as_os_str() == "codegen-llvm");
         let is_this_file = file.ends_with(this_file) || this_file.ends_with(file);
         let is_test_for_this_file =
             is_test && file.parent().unwrap().ends_with(this_file.with_extension(""));
@@ -488,6 +489,11 @@ pub fn check(path: &Path, tidy_ctx: TidyCtx) {
                 )
             }
 
+            if is_codegen_test && trimmed.contains("CHECK") && trimmed.ends_with(": br") {
+                err("`CHECK: br` and `CHECK-NOT: br` in codegen tests are fragile to false \
+                    positives in mangled symbols. Try using `br {{.*}}` instead.")
+            }
+
             if !under_rustfmt
                 && line.chars().count() > max_columns
                 && !long_line_is_ok(&extension, is_error_code, max_columns, line)
diff --git a/tests/codegen-llvm/char-ascii-branchless.rs b/tests/codegen-llvm/char-ascii-branchless.rs
index f99066aa9aaec..2cd5b5135a407 100644
--- a/tests/codegen-llvm/char-ascii-branchless.rs
+++ b/tests/codegen-llvm/char-ascii-branchless.rs
@@ -7,41 +7,41 @@
 // CHECK-LABEL: @is_ascii_alphanumeric_char
 #[no_mangle]
 pub fn is_ascii_alphanumeric_char(x: char) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.is_ascii_alphanumeric()
 }
 
 // CHECK-LABEL: @is_ascii_alphanumeric_u8
 #[no_mangle]
 pub fn is_ascii_alphanumeric_u8(x: u8) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.is_ascii_alphanumeric()
 }
 
 // CHECK-LABEL: @is_ascii_hexdigit_char
 #[no_mangle]
 pub fn is_ascii_hexdigit_char(x: char) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.is_ascii_hexdigit()
 }
 
 // CHECK-LABEL: @is_ascii_hexdigit_u8
 #[no_mangle]
 pub fn is_ascii_hexdigit_u8(x: u8) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.is_ascii_hexdigit()
 }
 
 // CHECK-LABEL: @is_ascii_punctuation_char
 #[no_mangle]
 pub fn is_ascii_punctuation_char(x: char) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.is_ascii_punctuation()
 }
 
 // CHECK-LABEL: @is_ascii_punctuation_u8
 #[no_mangle]
 pub fn is_ascii_punctuation_u8(x: u8) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.is_ascii_punctuation()
 }
diff --git a/tests/codegen-llvm/enum/enum-early-otherwise-branch.rs b/tests/codegen-llvm/enum/enum-early-otherwise-branch.rs
index 8d39d8e9b7466..4cadef3b6988a 100644
--- a/tests/codegen-llvm/enum/enum-early-otherwise-branch.rs
+++ b/tests/codegen-llvm/enum/enum-early-otherwise-branch.rs
@@ -12,7 +12,7 @@ pub enum Enum {
 pub fn foo(lhs: &Enum, rhs: &Enum) -> bool {
     // CHECK-LABEL: define{{.*}}i1 @foo(
     // CHECK-NOT: switch
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: [[SELECT:%.*]] = select
     // CHECK-NEXT: ret i1 [[SELECT]]
     // CHECK-NEXT: }
diff --git a/tests/codegen-llvm/issues/cows-dont-have-branches-117763.rs b/tests/codegen-llvm/issues/cows-dont-have-branches-117763.rs
index b97729fa14657..c143f7aeabfa4 100644
--- a/tests/codegen-llvm/issues/cows-dont-have-branches-117763.rs
+++ b/tests/codegen-llvm/issues/cows-dont-have-branches-117763.rs
@@ -9,7 +9,7 @@
 // CHECK-LABEL: @branchless_cow_slices
 #[no_mangle]
 pub fn branchless_cow_slices<'a>(cow: &'a std::borrow::Cow<'a, [u8]>) -> &'a [u8] {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: select
     // CHECK-NOT: icmp
     // CHECK: ret { ptr, {{i32|i64}} }
diff --git a/tests/codegen-llvm/issues/issue-107681-unwrap_unchecked.rs b/tests/codegen-llvm/issues/issue-107681-unwrap_unchecked.rs
index 69aefc6b1fb54..b8b9ea7436f33 100644
--- a/tests/codegen-llvm/issues/issue-107681-unwrap_unchecked.rs
+++ b/tests/codegen-llvm/issues/issue-107681-unwrap_unchecked.rs
@@ -11,7 +11,7 @@ use std::slice::Iter;
 #[no_mangle]
 pub unsafe fn foo(x: &mut Copied<Iter<'_, u32>>) -> u32 {
     // CHECK-LABEL: @foo(
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: select
     // CHECK: [[RET:%.*]] = load i32, ptr
     // CHECK-NEXT: ret i32 [[RET]]
diff --git a/tests/codegen-llvm/issues/issue-108395-branchy-bool-match.rs b/tests/codegen-llvm/issues/issue-108395-branchy-bool-match.rs
index 96387e791b03a..86bbbadcd9062 100644
--- a/tests/codegen-llvm/issues/issue-108395-branchy-bool-match.rs
+++ b/tests/codegen-llvm/issues/issue-108395-branchy-bool-match.rs
@@ -6,7 +6,7 @@
 // CHECK-LABEL: @wildcard(
 #[no_mangle]
 pub fn wildcard(a: u16, b: u16, v: u16) -> u16 {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     match (a == v, b == v) {
         (true, false) => 0,
         (false, true) => u16::MAX,
@@ -17,7 +17,7 @@ pub fn wildcard(a: u16, b: u16, v: u16) -> u16 {
 // CHECK-LABEL: @exhaustive(
 #[no_mangle]
 pub fn exhaustive(a: u16, b: u16, v: u16) -> u16 {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     match (a == v, b == v) {
         (true, false) => 0,
         (false, true) => u16::MAX,
diff --git a/tests/codegen-llvm/issues/issue-119422.rs b/tests/codegen-llvm/issues/issue-119422.rs
index 17ae71605b58d..2c553fd1fa876 100644
--- a/tests/codegen-llvm/issues/issue-119422.rs
+++ b/tests/codegen-llvm/issues/issue-119422.rs
@@ -19,45 +19,45 @@ pub fn check_non_null(x: NonNull<u8>) -> bool {
 // CHECK-LABEL: @equals_zero_is_false_u8
 #[no_mangle]
 pub fn equals_zero_is_false_u8(x: NonZero<u8>) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret i1 false
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.get() == 0
 }
 
 // CHECK-LABEL: @not_equals_zero_is_true_u8
 #[no_mangle]
 pub fn not_equals_zero_is_true_u8(x: NonZero<u8>) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret i1 true
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.get() != 0
 }
 
 // CHECK-LABEL: @equals_zero_is_false_i8
 #[no_mangle]
 pub fn equals_zero_is_false_i8(x: NonZero<i8>) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret i1 false
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.get() == 0
 }
 
 // CHECK-LABEL: @not_equals_zero_is_true_i8
 #[no_mangle]
 pub fn not_equals_zero_is_true_i8(x: NonZero<i8>) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret i1 true
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     x.get() != 0
 }
 
 // CHECK-LABEL: @usize_try_from_u32
 #[no_mangle]
 pub fn usize_try_from_u32(x: NonZero<u32>) -> NonZero<usize> {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: zext i32 %{{.*}} to i64
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret i64
     x.try_into().unwrap()
 }
@@ -65,9 +65,9 @@ pub fn usize_try_from_u32(x: NonZero<u32>) -> NonZero<usize> {
 // CHECK-LABEL: @isize_try_from_i32
 #[no_mangle]
 pub fn isize_try_from_i32(x: NonZero<i32>) -> NonZero<isize> {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: sext i32 %{{.*}} to i64
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret i64
     x.try_into().unwrap()
 }
@@ -75,9 +75,9 @@ pub fn isize_try_from_i32(x: NonZero<i32>) -> NonZero<isize> {
 // CHECK-LABEL: @u64_from_nonzero_is_not_zero
 #[no_mangle]
 pub fn u64_from_nonzero_is_not_zero(x: NonZero<u64>) -> bool {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret i1 false
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     let v: u64 = x.into();
     v == 0
 }
diff --git a/tests/codegen-llvm/issues/issue-73258.rs b/tests/codegen-llvm/issues/issue-73258.rs
index 936a75544966b..c9eceb0dccf73 100644
--- a/tests/codegen-llvm/issues/issue-73258.rs
+++ b/tests/codegen-llvm/issues/issue-73258.rs
@@ -18,7 +18,7 @@ pub enum Foo {
 pub unsafe fn issue_73258(ptr: *const Foo) -> Foo {
     // CHECK-NOT: icmp
     // CHECK-NOT: call
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: select
 
     // CHECK: %[[R:.+]] = load i8
@@ -26,14 +26,14 @@ pub unsafe fn issue_73258(ptr: *const Foo) -> Foo {
 
     // CHECK-NOT: icmp
     // CHECK-NOT: call
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: select
 
     // CHECK: ret i8 %[[R]]
 
     // CHECK-NOT: icmp
     // CHECK-NOT: call
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: select
     let k: Option<Foo> = Some(ptr.read());
     return k.unwrap();
diff --git a/tests/codegen-llvm/issues/num-is-digit-to-digit-59352.rs b/tests/codegen-llvm/issues/num-is-digit-to-digit-59352.rs
index 1d23eb2cdf9e4..4f5eea5f7e1c4 100644
--- a/tests/codegen-llvm/issues/num-is-digit-to-digit-59352.rs
+++ b/tests/codegen-llvm/issues/num-is-digit-to-digit-59352.rs
@@ -8,7 +8,7 @@
 // CHECK-LABEL: @num_to_digit_slow
 #[no_mangle]
 pub fn num_to_digit_slow(num: char) -> u32 {
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: panic
     if num.is_digit(8) { num.to_digit(8).unwrap() } else { 0 }
 }
diff --git a/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs b/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs
index 6f34097842800..1da7de535f75c 100644
--- a/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs
+++ b/tests/codegen-llvm/iter-repeat-n-trivial-drop.rs
@@ -19,23 +19,23 @@ impl Drop for NotCopy {
 // CHECK-LABEL: @iter_repeat_n_next
 pub fn iter_repeat_n_next(it: &mut std::iter::RepeatN<NotCopy>) -> Option<NotCopy> {
     // CHECK-NEXT: start:
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: %[[COUNT:.+]] = load i64
     // CHECK-NEXT: %[[COUNT_ZERO:.+]] = icmp eq i64 %[[COUNT]], 0
     // CHECK-NEXT: br i1 %[[COUNT_ZERO]], label %[[EMPTY:.+]], label %[[NOT_EMPTY:.+]]
 
     // CHECK: [[NOT_EMPTY]]:
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: %[[DEC:.+]] = add i64 %[[COUNT]], -1
     // CHECK-NEXT: %[[VAL:.+]] = load i16
     // CHECK-NEXT: store i64 %[[DEC]]
     // CHECK-NEXT: br label %[[EMPTY]]
 
     // CHECK: [[EMPTY]]:
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: phi i16
     // CHECK-SAME: [ %[[VAL]], %[[NOT_EMPTY]] ]
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK: ret
 
     it.next()
diff --git a/tests/codegen-llvm/option-as-slice.rs b/tests/codegen-llvm/option-as-slice.rs
index 39b34a2035b74..79cdd613aaadc 100644
--- a/tests/codegen-llvm/option-as-slice.rs
+++ b/tests/codegen-llvm/option-as-slice.rs
@@ -11,14 +11,14 @@ use core::option::Option;
 #[no_mangle]
 pub fn u64_opt_as_slice(o: &Option<u64>) -> &[u64] {
     // CHECK-NOT: select
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: switch
     // CHECK-NOT: icmp
     // CHECK: %[[LEN:.+]] = load i64
     // CHECK-SAME: !range ![[META_U64:[0-9]+]],
     // CHECK-SAME: !noundef
     // CHECK-NOT: select
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: switch
     // CHECK-NOT: icmp
     // CHECK: %[[T0:.+]] = insertvalue { ptr, i64 } poison, ptr %{{.+}}, 0
@@ -31,13 +31,13 @@ pub fn u64_opt_as_slice(o: &Option<u64>) -> &[u64] {
 #[no_mangle]
 pub fn nonzero_u64_opt_as_slice(o: &Option<NonZero<u64>>) -> &[NonZero<u64>] {
     // CHECK-NOT: select
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: switch
     // CHECK-NOT: icmp
     // CHECK: %[[NZ:.+]] = icmp ne i64 %{{.+}}, 0
     // CHECK-NEXT: %[[LEN:.+]] = zext i1 %[[NZ]] to i64
     // CHECK-NOT: select
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: switch
     // CHECK-NOT: icmp
     // CHECK: %[[T0:.+]] = insertvalue { ptr, i64 } poison, ptr %o, 0
@@ -50,7 +50,7 @@ pub fn nonzero_u64_opt_as_slice(o: &Option<NonZero<u64>>) -> &[NonZero<u64>] {
 #[no_mangle]
 pub fn u8_opt_as_slice(o: &Option<u8>) -> &[u8] {
     // CHECK-NOT: select
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: switch
     // CHECK-NOT: icmp
     // CHECK: %[[TAG:.+]] = load i8
@@ -58,7 +58,7 @@ pub fn u8_opt_as_slice(o: &Option<u8>) -> &[u8] {
     // CHECK-SAME: !noundef
     // CHECK: %[[LEN:.+]] = zext{{.*}} i8 %[[TAG]] to i64
     // CHECK-NOT: select
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: switch
     // CHECK-NOT: icmp
     // CHECK: %[[T0:.+]] = insertvalue { ptr, i64 } poison, ptr %{{.+}}, 0
diff --git a/tests/codegen-llvm/slice-init.rs b/tests/codegen-llvm/slice-init.rs
index 950e0b0c10db7..12e9df24565e1 100644
--- a/tests/codegen-llvm/slice-init.rs
+++ b/tests/codegen-llvm/slice-init.rs
@@ -69,7 +69,7 @@ const N: usize = 100;
 #[no_mangle]
 pub fn u16_init_one_bytes() -> [u16; N] {
     // CHECK-NOT: select
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: switch
     // CHECK-NOT: icmp
     // CHECK: call void @llvm.memset.p0
diff --git a/tests/codegen-llvm/slice-iter-fold.rs b/tests/codegen-llvm/slice-iter-fold.rs
index 55ab34661c36e..c63b5f8f7acdd 100644
--- a/tests/codegen-llvm/slice-iter-fold.rs
+++ b/tests/codegen-llvm/slice-iter-fold.rs
@@ -5,7 +5,7 @@
 #[no_mangle]
 pub fn slice_fold_to_last(slice: &[i32]) -> Option<&i32> {
     // CHECK-NOT: loop
-    // CHECK-NOT: br
+    // CHECK-NOT: br {{.*}}
     // CHECK-NOT: call
     // CHECK: ret
     slice.iter().fold(None, |_, i| Some(i))
diff --git a/tests/codegen-llvm/vecdeque-drain.rs b/tests/codegen-llvm/vecdeque-drain.rs
index a5e5da6501332..5709ead8bf939 100644
--- a/tests/codegen-llvm/vecdeque-drain.rs
+++ b/tests/codegen-llvm/vecdeque-drain.rs
@@ -10,7 +10,7 @@ use std::collections::VecDeque;
 
 // CHECK-LABEL: @clear
 // CHECK-NOT: call
-// CHECK-NOT: br
+// CHECK-NOT: br {{.*}}
 // CHECK: getelementptr inbounds
 // CHECK-NEXT: {{call void @llvm.memset|store}}
 // CHECK-NEXT: ret void
@@ -21,15 +21,15 @@ pub fn clear(v: &mut VecDeque<i32>) {
 
 // CHECK-LABEL: @truncate
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK-NOT: br
+// CHECK-NOT: br {{.*}}
 // CHECK: ret void
 #[no_mangle]
 pub fn truncate(v: &mut VecDeque<i32>, n: usize) {
@@ -40,17 +40,17 @@ pub fn truncate(v: &mut VecDeque<i32>, n: usize) {
 
 // CHECK-LABEL: @advance
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK: br
+// CHECK: br {{.*}}
 // CHECK-NOT: call
-// CHECK-NOT: br
+// CHECK-NOT: br {{.*}}
 // CHECK: ret void
 #[no_mangle]
 pub fn advance(v: &mut VecDeque<i32>, n: usize) {